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Lin, Chunyu. "Studies on the Porphyrin and Phthalocyanine Modified on Sno2 Photoelectrochemical Cells." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc407761/.
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The world is facing a tough challenge regarding fulfilling human energy needs. Scientists are motivated to find alternative ways to the fossil fuel at a lower cost with little or no environmental pollution. Among the available renewable resources, the solar energy is an alternative energy to fossil fuel. Scientists are engaged in mimicking the photosynthesis to create the new energy devices such as dye sensitized solar cells. The fundamental theory and properties of the dye sensitized solar cells is given in the first chapter. In this research, the application of the different methods for surface alteration of SnO2 with water soluble porphyrins and phthalocyanine is studied. Using optical absorbance and steady state fluorescence studies, the formation of porphyrins and phthalocyanine discuss on the SnO2 surface is shown. Moreover, the different results of photoelectrochemical cells are show on chapter 2 to understand the porphyrin and phthalocyanine modified on SnO2 as electron injector. In summary, the application porphyrin and phthalocyanine of dimers as a broad band capturing photosensitized dye is discussed.
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Lima, Michael Augusto Souza de. "Vulnerabilidade e prevenção às DST’s nas práticas afetivo-sexuais de lésbicas." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/8184.
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Introduction: The present study had as general objective to analyze the vulnerability and preventive practices against sexually transmitted diseases (STDs) affective-sexual relations. Methods: this was an exploratory study and descriptive, transversal and qualitative character. The sample was composed of 18 participants defined lesbian women, with ages ranging from 19 to 42 years (M = 26; DP = 6.1). For the collection of data was used a demographic questionnaire and semi-structured interviews. The collection came from a participant matrix and followed the selection of new participants by the method of "snowball". The data from the demographic questionnaire were analyzed through descriptive statistics in PASW Statistics Software (SPSS) for Mac-23 version, the data obtained in the interviews were analyzed by analyzing thematic category MAXQDA software 11-Data Analysis Qualitative Software (qualitative data analysis Software). Results: Were applicants in the accounts the idea of greater vulnerability associated with the male presence in the relationship, getting behind in speeches that the only relationship between women could be a protective factor. Reports emerged about the absence of further clarification about the existence, use and effectiveness of preventive inputs to STD's that can be used in relations between women. Were highlighted in the speeches that the alleged methods available would not own, or designed to prevent the STDs among women, considering that most of these means of prevention would be adaptations of existing methods, as the male condom or unlubricated adaptations of items which originally would be used for other purposes (plastic film, PVC gloves, latex barrier use in dentistry). Confidence in the partnership and in the existence of a presumed fidelity were cited as elements of prevention strategies. The bias was related to lack of campaigns that drive the lesbians on the need to prevent sexual relations, and stigma to the myth that lesbians would be marginalized women. The presence of the element constraint was highlighted as a factor preventing the search for Gynecological medical care. The lack of preparation of health professionals emerged as an element that can influence on increasing the vulnerability of this population health. More than half of the participants stated that often reveal their sexual orientation to doctors gynecologists, which may indicate a breakthrough for Lesbian visibility. It is concluded that the factors of programmatic can influence more evident to the worsening in the situations of vulnerability to health of lesbians, although elements of individual and social dimension also are associated and these misdeeds. These findings may serve as a framework that highlights elements of individual, social order, as well as deficiencies in programmatic, that relate and can influence for the most vulnerable situation in health of lesbians.
Introdução: O presente estudo teve como objetivo geral analisar a vulnerabilidade e as práticas preventivas frente às Doenças Sexualmente Transmissíveis (DST`s) nas relações afetivo-sexuais de lésbicas. Método: Tratou-se de um estudo exploratório e descritivo, de caráter transversal e qualitativo. A amostra foi composta por 18 participantes mulheres que se autodefinem lésbicas, com idades variando de 19 a 42 anos (M=26; DP=6,1). Para a coleta dos dados foram utilizados um questionário sociodemográfico e entrevistas semiestruturadas. A coleta partiu de uma participante matriz e seguiu a seleção de novas participantes pelo método de “bola de neve”. Os dados oriundos do questionário sociodemográfico foram analisados por meio de estatísticas descritivas no Software PASW Statistics (SPSS) for Mac - versão 23, os dados obtidos nas entrevistas foram analisados por meio da análise categorial temática através do software MAXQDA 11 - Qualitative Data Analysis Software (Software de Análise de Dados Qualitativos). Resultados: Foram recorrentes nos relatos a ideia de maior vulnerabilidade associada a presença masculina na relação, ficando subjacente nos discursos que o relacionamento apenas entre mulheres poderia ser um fator de proteção. Emergiram relatos sobre a ausência de maiores esclarecimentos acerca da existência, formas de uso e eficácia de insumos preventivos às DST’s que possam ser utilizados nas relações entre mulheres. Foram evidenciados nos discursos que os supostos métodos existentes não seriam próprios, específicos ou pensados para na prevenção às DST’s entre mulheres, tendo em vista que a maioria destes meios de prevenção seriam adaptações de métodos já existentes, como o preservativo masculino sem lubrificação ou adaptações de itens que originalmente seriam utilizados com outras finalidades (plástico filme de PVC, luvas, barreira de látex de uso odontológico). A confiança na parceria e na existência de uma fidelidade presumida foram elementos citados como estratégias de prevenção. O preconceito foi relacionado à ausência de campanhas que orientem às lésbicas sobre a necessidade de prevenção nas relações sexuais, e o estigma ao mito de que lésbicas seriam mulheres marginalizadas. A presença do elemento constrangimento foi destacado como um fator impeditivo para a busca por atendimento médico ginecológico. A falta de preparo dos profissionais de saúde emergiu como um elemento que pode influenciar no aumento da vulnerabilidade em saúde desta população. Mais da metade das participantes afirmaram que costumam revelar sua orientação sexual aos médicos ginecologistas, o que pode indicar um avanço para à visibilidade lésbica. Conclui-se que fatores de ordem programática podem influenciar de maneira mais evidente para o agravo nas situações de vulnerabilidade a saúde de lésbicas, embora elementos de dimensão individual e social também estejam associados e estes agravos. Estes achados podem servir como um quadro que evidencia elementos de ordem individual, social, bem como deficiências programáticas, que se relacionam e podem influenciar para a situação de maior vulnerabilidade em saúde das lésbicas.
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Hasin, Panitat. "Developing New Types of Electrode Materials for Dye-Sensitized Solar Cells (DSSCs)." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1258071882.
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Zoppa, Robert J. "The future use of DSCS and commercial satellites in the U.S. Navy." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA285707.
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Thesis (M.S. in Systems Technology (Space Systems Operations)) Naval Postgraduate School, September 1994.Thesis advisor(s): Dan C. Boger. "September 1994." Bibliography: p. 96-97. Also available online.
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Hernández, Redondo Ana. "Copper(I) polypyridine complexes : the sensitizers of the future for dye-sensitized solar cells (DSSCs) /." [S.l.] : [s.n.], 2009. http://edoc.unibas.ch/diss/DissB_8757.
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Hua, Yong. "Design and synthesis of new organic dyes for highly efficient dye-sensitized solar cells (DSSCs)." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/71.
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Dye-sensitized solar cell (DSSC) has attracted increasing interest as a promising hybrid organic-inorganic solar cell. At the heart of the device is a photosensitizer, which is anchored onto a wide-bandgap semiconducting metal oxide. It harvests solar light and transfers the energy via electron transfer to a suitable material (e.g. TiO2) to produce electricityas opposed to chemical energy in plant. The topic of this thesis focuses on the design and synthesis of metal-free organic dyes for applications in DSSCs. Specific attention has been paid to the correlation between the molecular structures and physical properties, as well as their performances in DSSCs. Chapter 1 presents the major components and working principle of DSSC, following by a brief overview of the development of organic dyes and their application in DSSCs. In chapter 2, we have designed two types of new phenothiazine-based dyes to investigate the positioning effect a donor group on the cell performance. The structural features of a donor aryl group at the C(7) position of phenothiazine core extend the π-conjugation of the chromophore and efficiently suppress the dye aggregation on TiO2 film. As a result, Type 1 dyes have better light harvesting properties in contact with TiO2 films, and give much better photovoltaic performance than Type 2 dyes. Chapter 3 presents the synthesis and characterization of a series of simple phenothiazine-based dyes, in which, a linear electron-rich (4-hexyloxy)phenyl group at C(7) of the phenothiazine periphery as the donor, and an alkyl chain with different length at N(10). The dye molecules show a linear shape which is favorable for the formation of a compact dye layer on the TiO2 surface, while their butterfly conformations can sufficiently inhibit molecular aggregation. Moreover, the alkyl substituents with different chain length at N(10) could further optimize the performance through complete shielding the surface of TiO2 from the Iˉ/I3ˉ electrolyte. Under simulated AM 1.5G irradiation, the PT-C6 based DSSC produces a short-circuit photocurrent of 15.32 mAcm−2, an open-circuit photovoltage of 0.78 V, a fill factor of 0.69, corresponding to a power conversion efficiency (PCE) of 8.18%. Moreover, we designed a stepwise approach for co-adsorption of the organic dye PT-C6 with a porphyrin dye (ZnP) for DSSCs. Upon optimization, the device made of the PT-C6 + ZnP system yielded Jsc = 19.36 mA cm-2, Voc =0.735 V, FF = 0.71 and η = 10.10%. In chapter 4, we further developed five organic dyes appended with T, TT, E, ET, or EE (T and E denote thiophene and 3,4-ethylenedioxythiophene (EDOT), respectively) on the C(7) atom of phenothiazine core as electron donors. We have also analyzed the structure-performance corelations of dye molecules in the aspect of dye aggregation, electron injection, dye regeneration and interfacial charge recombination of electrons with electrolytes and/or oxidized dye molecules, through DFT calculation, impedance analysis and transient photovoltage studies. In chapter 5, we extended our studies by using phenothiazine as a building block to construct 3D bulky organic dyes. We systematically investigated the influence of 3D bulky substituents on dye aggregation and charge recombination, as well as photovoltaic performance of DSSCs. The molecular design strategy demonstrates that high Voc can be realized by employing 3D-phenothiazine dyes featuring a bulky substituent, such as, hexylcarbazole and dihexylfluorene units. Impressively, the co-adsorbent-free DSSCs based on dye TP3 exhibits a photovoltaic performance with efficiency up to 8.00 %. In order to realize a panchromatic absorption and further enhance the energy conversion efficiency of DSSCs, we also designed a stepwise approach for co-adsorption of the organic dye TP3 with a NIR dye YR6 for co-sensitized DSSCs. Upon optimization, the device made of the TP3 + YR6 system yielded Jsc = 19.18 mA cm-2, Voc =0.721 V, FF = 0.712 and η = 9.84 %. The power-conversion efficiency is the highest reported efficiency for a squaraine dye-based co-sensitized panchromatic DSSCs. From chapters 6 and 7, a series of new simple panchromatic dyes based on thiadiazolo[3,4-c]pyridine (PyT) have been designed for panchromatic DSSCs. These new organic dyes exhibit broad absorption spectrum in the range of 300~850 nm and high molar extinction coefficients. The electrochemical analyses demonstrate that the incorporation of the auxiliary electron-deficient thiadiazole[3,4-c]pyridine unit can fine-tune the HOMO and LUMO energy levels and red-shift the absorption spectra to NIR region. The overall conversion efficiencies of liquid-electrolyte DSSCs based on these sensitizers range from 0.46 to 6.30 %. We draw some conclusions in chapter 8 together with the outlooks in DSSCs
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Spiassi, Ana Lúcia. "Conversas com o movimento social negro sobre vulnerabilidades em relação às DSTs/Aids." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5137/tde-04052011-170701/.
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A intensificação do debate sobre a epidemia de DST/aids na população negra, trazida por entidades da sociedade civil na última década, aparece na esteira da recente sistematização de políticas voltadas para a saúde desta população. O objetivo do presente estudo foi conhecer a avaliação que o movimento social negro do ABC paulista tem sobre as condições de vulnerabilidade em relação às DST/aids vividas pelos cidadãos negros da região. Trata-se de estudo qualitativo, construído com base em entrevistas individuais em profundidade com lideranças diversas deste movimento. A representatividade dos entrevistados foi ancorada no conceito de Luta por Reconhecimento e a estrutura das entrevistas foi organizada a partir do conceito teórico orientador de todo o trabalho que é o conceito de Vulnerabilidade. A construção e interpretação das entrevistas foram apoiadas em uma concepção de linguagem entendida como desveladora de processos de interação a partir do cotejo de duas tradições filosóficas principais: o materialismo histórico dialético e a hermenêutica. As avaliações dos entrevistados sobre as três dimensões de vulnerabilidades vivenciadas pelos negros em relação às DST/aids, produziram um quadro no qual diversas situações cotidianas são relatadas e discutidas. No plano institucional, três grupos centrais de problemas foram levantados: as condições de atendimento nos serviços de saúde; a atuação do Estado sobre as condições de iniquidade e a relação do Estado com o movimento social. Em relação às vulnerabilidades sociais, foram destacadas as desigualdades sócio-econômicas entre negros e não-negros e suas consequências, que incluem a persistência de baixa escolaridade, precarização das moradias, fixação da população negra para a periferia das áreas urbanas, barreiras à ascensão social, desigualdades sociais em saúde e a persistência da discriminação racial nas relações sociais. Em relação às vulnerabilidades individuais, os entrevistados relataram algumas de suas vivências pessoais e familiares em que sobressaem os sentimentos de insegurança e desrespeito trazidos pela tensão da discriminação racial, o que tem implicações não apenas morais, mas manifesta-se também no modo como os sujeitos vivenciam, apreendem e lidam com os aspectos dos demais planos de vulnerabilidade, acima citados. Os entrevistados apontaram, ainda, alternativas de reconstrução prática com potencial de redução do impacto da vulnerabilidade para a aids entre os brasileiros negrosThe intensified discussion about the STD/AIDS epidemic among black population, brought about by civil society organizations in the last decade, appears in the wake of recent policies aimed at health of this population. The objective of this study was to explore the assessment that the black social movement in the ABC region (State of SP) make about vulnerability conditions regarding STD/AIDS experienced by black citizens from the region. This is a qualitative study, built on individual in-depth interviews with several leaders of this movement. Representativeness of respondents was based on the concept of \"Struggle for Recognition\", and the structure of the interviews on the theoretical concept of Vulnerability that guided the whole work. The structure and interpretation of interviews were backed by designing a language understood as unfolding processes of interaction based on confrontation of two major philosophical traditions: historical dialectical materialism and hermeneutics. The evaluations of the respondents about the three dimensions of vulnerability experienced by brazilian blacks in relation to STD/AIDS, resulted in a framework in which many daily situations are reported and discussed. At institutional level, three core groups of issues were raised: the conditions of care in health services, State action concerning inequity conditions and the relation between the State and social movements. As to social vulnerabilities, socioeconomic inequalities and their consequences were highlighted between blacks and non-blacks, including persistence of low schooling, precarious housing, setting the black population in the periphery of urban areas, barriers to social mobility, health inequalities and persistence of racial discrimination in social relations. In relation to individual vulnerabilities, respondents reported some of their personal and family experiences that stress feelings of lack of confidence and disrespect due to tension resulting from racial discrimination, which has moral implications and also manifests in how the subjects experience, perceive and deal with vulnerability aspects at other levels, as mentioned above. Yet, the interviewees pointed out practical reconstruction alternatives with potential to reduce the impact of vulnerability to AIDS among black Brazilians
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Recuero, Maira Guedes Piltcher. "INVESTIGANDO POSSÍVEIS IMPACTOS DAS POLÍTICAS PÚBLICAS DE PREVENÇÃO A DSTs / HIV EM ADOLESCENTES." Universidade Catolica de Pelotas, 2008. http://tede.ucpel.edu.br:8080/jspui/handle/tede/34.
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Previous issue date: 2008-06-13This article has as a purpose to know the prevention politics for Sexual Transmitted Diseases/SIDA of the Ministry of Health of Brazil, proposed to teenagers, and, supported on this analysis, to evaluate the impact suffered for them. As a methodology, the researcher used as a procedure the qualitative research, recording interviews. These interviews were made in two schools from Pelotas, with 12-18 year teenagers, selected without any specific criteria. Then, the researchers analyzed the content of the interviews, limiting this not only to analysis on the teenagers recognition of the prevention politics, but also on the changes needed to this behavior become effective. The collected data was transcripted in order to a posterior examination and classified into categories. These categories were emerged from the oral interviews. The investigators observed the existence of differences between the proposed politics and the developed actions, thus not contributing to adoption of less risky health behaviors. The results showed that the basis of all prevention politics may be centered in a citizen building
Este trabalho tem como objetivo conhecer as políticas de prevenção a DSTs/HIV do Ministério da Saúde do Brasil, propostas a adolescentes, e, com base nessa análise, avaliar os impactos que tais políticas exercem sobre eles. Para tanto, procedeu-se a uma pesquisa qualitativa, usando-se entrevistas gravadas como método. Estas foram realizadas em duas escolas na cidade de Pelotas, com adolescentes em idade de 12 a 18 anos, selecionados de forma aleatória. Fundamentando-se no exame do conteúdo dos depoimentos, procurou-se delimitar o reconhecimento, pelos adolescentes, das políticas o desenvolvidas com esse intuito, bem como identificar as mudanças desencadeadas a um comportamento preventivo eficaz. Os dados coletados foram transcritos a fim de posterior exame e classificação das categorias que emergiram das falas. Observou-se a existência de uma dissociação entre as políticas propostas e as ações desenvolvidas, e, desta maneira, não contribuindo para adoção de comportamentos menos arriscados à saúde. Os resultados apontaram que a base de todo trabalho de prevenção, visando à mudança de comportamento, deve estar centrado na construção da cidadania, objetivando atingir seu propósito
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Osborn, Robert John. "Isolation of ambient aerosols of known critical supersaturation: the differential critical supersaturation separator (DSCS)." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/5987.
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A field-deployable instrument has been developed that isolates from an ambient aerosol population only those particles that have critical supersaturations, Sc, within a narrow, user-specified, range. This Differential Critical Supersaturation Separator (DScS) is designed to supply one or more particle size and/or composition analyzers to permit the direct examination of the factors that influence the activation properties of ambient aerosols. The DScS consists of two coupled parallel plate continuous flow thermal gradient diffusion cloud chambers housed within a single enclosure. Descriptions of instrument operation, construction and calibration data collected, when pure ammonium sulfate aerosols were injected into the DScS for operation at 0.15%< Sc<0.175%, 0.30%< Sc<0.35%, and 0.60% < Sc<0.70%, are included. Following instrument development, the DScS was deployed during March 2006 for the Megacities Impact on Regional And Global Environment (MIRAGE) field campaign in Mexico City, Mexico. Throughout the MIRAGE field campaign a Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) system measured aerosol size distributions and size-resolved hygroscopicity of DScS separated aerosol. The dry diameter (Dp*) of particles sampled in the TDMA system as well as the known Sc prescribed in the DScS were combined in a modified version of Köhler Theory to make predictions of particle hygroscopicity. These predictions frequently overestimated the measurements. Further analysis of DScS separated aerosols compares the known particle Sc to a predicted particle Sc, providing insight into particle activation efficiency. Overall, the sampled aerosol exhibited properties that indicate they were more efficient at activation than Köhler Theory would predict.
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Ribeiro, Karla Carolina Silveira. "Adolescência e sexualidade: vulnerabilidade às DSTS, HIV/AIDS e a gravidez em adolescentes paraibanos." Universidade Federal da Paraíba, 2011. http://tede.biblioteca.ufpb.br:8080/handle/tede/6878.
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Previous issue date: 2011-12-01Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Based on the conception that beliefs concerning sexuality play an important role in the behavior of adolescents, it was used the Foucault‟s perspective in order to identify the characteristics and analyze the possible associations among the pregnancy in the adolescence, the STDs/AIDS, and the situations of vulnerability of adolescents who live in the state of Paraíba. The sample comprised 8.741 adolescents, been 62% female, in the age range of 12 to 20 years old (average of 16 years old), enrolled in public schools of 34 cities classified based on the demographic size according to the city social indicators. It was used a self-report structured questionnaire and the group technique of focal discussion. In order to analyze the quantitative date, it was used descriptive statistics, been used position and variability measures, besides it, it was performed bivariate tests. The analysis of the group‟s content was performed based on Categories which were determined based on the emerged themes. According to the results, three thematic categories have emerged. The first, which was denominated Sexual Practice (sub-categories: Sexual Initiation and Determinant Factors); the second was denominated Prevention (sub-categories: The Use of Condom and Contraceptive Methods); and the third category, Vulnerability to AIDS (sub-categories: Perception of Vulnerability and Information). Concerning to the Sexual Practice, 2.732 participants declared have an active sexual life (31%), with initiation in 15,6 years old to the women and 14,6 years old to men, with significant statistical difference in relation to the sex (64% male p < 0,001) and the size of the cities (minor indices in medium size cities). The differentiation of gender was also obtained in relation to the first sexual partner, mainly related to the age (average of 21 years old to women and 16 years old to men p < 0,05), been justified by the higher experience, responsibility, especially in the case of an undesired pregnancy. As factors which predispose to precocious sexual initiation, it was mentioned: the influence of couples, of media, the beliefs and cultural norms, and the use of alcohol. In the second category, Prevention, the nonsystematic use of condom was related to the inexperience, to the existence of negative beliefs, to the unpredictability of the action, to the difficult of obtainment and access, to the lack of information and sort of affective relationship. Only 59% of the adolescents declared to have some knowledge about contraceptive methods, been highlighted the male condom (43%) and the pill (33%), and the major knowledge by the female adolescents (80%). It was described the occurrence of 195 cases of pregnancy and 75 cases of abort. The reasons which led the pregnancy in adolescents are the lack of care, difficulty in the access to the contraceptive method and the guarantee of continuation of the relationship. In the category Vulnerability to AIDS, 83% of the adolescents who had already sexual relations did not think themselves as vulnerable and 15% of the total declared not receive information concerning HIV/AIDS. As sources of information were mentioned school (59%), family (22%), media (18%), and health professionals (16%); this last source with a higher percentage to the women and in the rural area. It is concluded that the normative social speech, mainly associated to the gender roles, reveal beliefs and behaviors in this stage of life, causing more female difficulty to the prevention. It was also observed that the information passed to this population still are presented as biological and moralist, putting in evidence the necessity of interventions which comprises beliefs and norms assumed by this population.
Partindo do pressuposto de que as concepções conferidas à sexualidade têm papel decisivo no comportamento dos adolescentes, fez-se uso da perspectiva foucaultiana com o objetivo de identificar as características e analisar as possíveis associações entre a gravidez na adolescência e as DSTs/AIDS às situações de vulnerabilidade de adolescentes residentes no Estado da Paraíba. A amostra foi composta por 8.741 adolescentes, sendo 62 % do sexo feminino, na faixa etária de 12 a 20 anos (média de 16 anos), matriculados em escolas públicas de 34 cidades classificados pelo porte demográfico de acordo com os indicadores sociais municipais. Como instrumento foi utilizado um questionário estruturado auto-aplicável e a técnica de grupo de discussão focal. Para análise dos dados quantitativos, utilizou-se de estatística descritiva, com a utilização de medidas de posição e de variabilidade, além da realização de testes bivariados. A análise dos conteúdos dos grupos foi realizada com base em Categorias determinadas a partir dos temas suscitados. A partir dos resultados, emergiram três categorias temáticas. A primeira denominada Prática Sexual (sub-categorias: Iniciação Sexual e Fatores Determinantes); a segunda denominada Prevenção (sub-categorias: Uso de Preservativo e Métodos Anticoncepcionais); e a terceira categoria, Vulnerabilidade à AIDS (sub-categorias: Percepção de Vulnerabilidade e Informações). No que se refere à Prática Sexual, 2.732 participantes declaram ter vida sexual ativa (31%), com iniciação aos 15,6 anos para o sexo feminino e aos 14,6 anos para o masculino, com diferença estatisticamente significante em relação ao sexo (64% masculino - p<0,001) e porte das cidades (menor índice em cidades de médio porte). A diferenciação de gênero também se manteve em relação ao primeiro parceiro sexual, principalmente em relação à idade (média de 21 anos para o feminino e 16 anos para o masculino - p<0,05), justificado pela maior experiência, responsabilidade, principalmente no caso de uma gravidez indesejada. Como fatores que predispõem à iniciação sexual precoce, foram citados: a influência dos pares, da mídia, as crenças e normas culturais e, o uso de álcool. Na segunda categoria, Prevenção, o uso assistemático do preservativo foi relacionado à inexperiência, a existência de crenças negativas, a imprevisibilidade do ato, a dificuldade de obtenção ou acesso, falta de informações e tipo de vínculo afetivo. Apenas 59% dos adolescentes afirmaram possuir algum conhecimento dos métodos contraceptivos, destacando-se o preservativo masculino (43%) e a pílula (33%), e o maior conhecimento pelas adolescentes (80%). Foi relatada a ocorrência de 195 casos de gravidez e 75 casos de aborto. Os motivos que levam a gravidez na adolescência é o descuido, dificuldade no acesso ao anticoncepcional e a garantia da manutenção do relacionamento. Na categoria Vulnerabilidade à AIDS, 83% dos adolescentes que já tiveram relação sexual não se percebem vulneráveis e 15% do total relataram não receber informações sobre o HIV/AIDS. Como fontes de informação foram citadas a escola (59%), família (22%), mídia (18%) e profissionais de saúde (16%), este último com maior percentual para o feminino e na zona rural. Conclui-se que os discursos sociais normalizantes, principalmente vinculados aos papeis de gênero, demarcam crenças e comportamentos nesta fase da vida, provocando maior dificuldade feminina na prevenção. Observou-se também que as informações repassadas a essa população ainda se apresentam de forma biológica e moralista, colocando em pauta a necessidade de intervenções que abordem as crenças e normas assumidas por essa população.
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Ribeiro, Karla Carolina Silveira. "Intervenção psicoeducativa dirigida à prevenção de DSTs e gravidez não planejada para adolescentes jovens." Universidade Federal da Paraíba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/6947.
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Previous issue date: 2013-03-07Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Questões socioculturais e econômicas aumentam a vulnerabilidade dos jovens à infecção pelas DSTs/HIV e ao risco de uma gravidez não planejada, devendo ser abordados nas estratégias de prevenção, tendo em vista que a educação se desenvolve em espaços formais e não formais desde que haja interação entre as pessoas e saberes. Partindo destes pressupostos, este estudo está fundamentado na teoria da Vulnerabilidade e na teoria do Comportamento Planejado, tendo como objetivo elaborar e verificar os efeitos da aplicação de uma estratégia de intervenção psicoeducativa para a prevenção das DSTs e gravidez não planejada para adolescentes jovens, enfocando de modo abrangente e integrado os aspectos da vulnerabilidade individual, social e programático. Trata-se de um estudo com delineamento quase-experimental com grupo de controle, que se divide em 03 estudos: (1) Construção e Validação de um instrumento de avaliação da percepção de vulnerabilidade adolescente jovem para uso no pré e pós-teste. (2) Construção de uma estratégia de intervenção psicoeducativa. (3) Aplicação e avaliação da intervenção psicoeducativa. A população do estudo é constituída por jovens de 14 a 24 anos, matriculados em escolas públicas e privada de ensino médio da cidade de João Pessoa. Para o primeiro estudo, a amostra foi constituída por 432 estudantes, no qual foi aplicada a escala de Percepção frente à Vulnerabilidade. A escala foi construída através das bases teóricas da teoria da Vulnerabilidade e os seus itens foram delineados a partir de estudo anterior. A partir da Análise Fatorial dos Componentes Principais e o alpha de Crombach, obteve-se um instrumento com 29 itens, dividido em três fatores de vulnerabilidade individual, social e programático -, confirmando os pressupostos teóricos e evidencias empíricas. No segundo estudo foi construída uma intervenção psicoeducativa nos moldes de oficinas, com base na Teoria da Vulnerabilidade e Teoria do comportamento Planejado. A intervenção resultou em três encontros em dias consecutivos no qual foram discutidas a iniciação sexual, as ideologias de gênero, negociação e uso do preservativo, DST e gravidez, crenças e normas sociais. Para análise dos resultados foram gravados os 15 minutos finais de cada dia, no qual foi discutida a percepção dos participantes sobre a intervenção, transcritos e analisados por categorização temática. Os dados demonstraram sua adequação ao publico alvo. O terceiro estudo ocorreu em quatro instituições escolares pública e privada, onde foram formados randomicamente dois grupos (experimental e controle), compostos em média por 10 alunos, equiparados em relação a sexo. Após a aplicação do pré-teste, o grupo experimental participou da oficina psicoeducativa, enquanto para o grupo controle foram realizadas palestras informativas. Os debates realizados no grupo experimental foram gravados (autorização dos participantes). Passados 4 meses da intervenção, foi aplicado o pós-teste, cuja eficácia foi verificada através do test t para amostras emparelhadas. Para os dados qualitativos referentes aos relatos dos participantes durante o processo de Intervenção Psicoeducativa, foi utilizada Análise Categorial Temática. Os resultados provenientes do grupo experimental e controle demonstraram que a intervenção psicoeducativa se mostrou eficaz na mudança da percepção de vulnerabilidade individual (p<0,05), decréscimo no primeiro e aumento no segundo grupo. No que tange os dados qualitativos emergiram quatro Classes Temáticas: Vulnerabilidade Social (Crenças Normativas); Vulnerabilidade Programática (Acesso ao Insumo); Vulnerabilidade Individual (Uso do Preservativo, Crenças de Gênero e Informação); e Ressignificação após Intervenção (Autopercepção e Autocuidado). Conclui-se, portanto, que a presente pesquisa alcançou o objetivo proposto, demonstrando a necessidade de intervenções que priorize as relações intersubjetivas, o que possibilita a construção de sujeito-cidadão.
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Vladimir, Shuster. "Phenazine: A Building Block for Multinuclear and Heterometallic Complexes, Where the Ligand Acts as an Electron Acceptor and Radical Abstractor." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/24234.
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Over the past decade, intensive academic and commercial interests have been paid on compounds possessing photochemical properties, namely for their preparation, chemical properties, high efficiency and potential low-cost.
Compounds having intense photochemical properties gained great interest due to wide range of potential applications. The sensitizers are one of the key components for high power-conversion efficiency in the dye sensitized solar cells (DSSCs). They are the core components in the organic light-emitting devices (OLEDs) due to their ability to emit light with the wavelengths largely red- shifted from their absorption wavelength. Ruthenium based sensitizers have been tagged “molecular light switches” because, although the fluorescence of these complexes in aqueous solutions is negligible, it increases of greater than 10000 fold in the presence of DNA. Many polypyridyl and dipyrido phenazine ruthenium complexes have achieved high power conversion efficiencies and therefore are of practical interest. Several research groups stated that the dipyrido phenazine ligand may be thought of as comprising two components: a bipyridyl unit and a phenazine unit. These two subunits behave essentially separately, with many molecular orbitals being localised over only one subunit and a redox properties of central phenazine moiety in the dipyrido phenazine ligand are important for the photochemical applications.
Therefore a phenazine ligand was selected as a model for the present investigation. The chemistry of phenazine ligand is mostly limited to the late transition metal and f - element complexes. Our laboratory has a rich backgroung in the aluminum and early transition metal chemistry. The aluminum chemistry and early transition metal chemistry are of great interest since aluminum and early transition metal complexes are environmentally friendlier and cheaper than the late transition metal compounds. Another drawback of the ruthenium-based sensitizers is the lack of absorption in the red region of the visible spectrum, and also low molar extinction coefficients. An essential requirement for efficient conversion of solar energy is the good spectral match of the sensitizer absorption to the emission spectrum of solar radiation. In this regard, the ruthenium sensitizers’ spectral response in the lower energy regions is not sufficient.
The current project has three parts. In the first part we collected and reviewed known literature regarding the certain classes of non-innocent ligands containing the six-membered carbon- nitrogen heterocycles and regarding the ligands potentially important for the photochemical applications. We also reviewed all available to the data information about the complexes supported by the phenazine ligand.
In the second part we have investigated interaction of alkylaluminum compounds and phenazine and observed reduction of phenazine accompanied by formation of dialuminum cage type compounds containing two formally mononegative phenazine ligand. The derivatization of phenazine has been also observed. It resulted in formation of compounds having a stable organic radical.
In a third part of our project we have explored interaction of phenazine or thiophenazine with the alkylaluminum compounds and chromium dichloride. The reaction in the three component system resulted in reduction of phenazine ligand and lead to the heterometallic Cr(II) - aluminum complexes containing a formally dinegative phenazine or thiophenazine ligands. When a large excess of triethylaluminum was taken, reduction of phenazine and chromium has been observed leading to the heterometallic multinuclear Cr(I) - aluminum complex containing a formally dinegative phenazine ligands and two chromium atoms in one complex in the rare oxidation state one.
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Cardoso, Raimundo Luis Silva. "VULNERABILIDADES ÀS DSTs/AIDS ENTRE JOVENS DE UMA COMUNIDADE QUILOMBOLA DO MUNICÍPIO DE TURIAÇU-MA." Universidade Federal do Maranhão, 2011. http://tedebc.ufma.br:8080/jspui/handle/tede/1080.
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Previous issue date: 2011-10-28The research aims to reflect the vulnerability of young people with sexually transmitted diseases in a Quilombola community Jamary dos Pretos in the municipality of Turiaçu-MA. The discussion also encompasses access to information about prevention of STDs/AIDS. The analysis involves concepts of multi-disciplinary areas of knowledge: history, anthropology, health, and society. Covers the concepts of history of black communities in Maranhão, and its association with the past of slavery and its appreciation and depreciation by sectors of society and the effect of the training process of the current modern society. Analyses the socioeconomic status of young people in this community as a member of several factors for the composition of this vulnerability. Still evaluates policies for the prevention, control and treatment of STDs / AIDS in this population segment. We opted for a quantitative survey-type approach, using as a Data collection instrument a form closed questions to 50 youths in the community, located in the age group 18 to 24 years. Among the results, include: poor education, unemployment and household income less than a minimum wage that make impossible young people have access to means of protection and prevention of STDs / AID; most young people do not realize the risk of STD / AIDS that are exposed, revealed a risk behaviors adopted by young people, such as disuse of condoms during sexual intercourse and injecting drug use.
A pesquisa tem por objetivo refletir a vulnerabilidade dos jovens às doenças sexualmente transmissíveis em uma comunidade quilombola Jamary dos Pretos existente no município de Turiaçu MA. A reflexão engloba ainda o acesso à informação sobre prevenção de DST/AIDS. A análise envolve conceitos de áreas multidisciplinares de conhecimento: história, antropologia, saúde e sociedade. Aborda os conceitos de história das comunidades negras no Maranhão, bem como sua associação com o passado escravagista e sua valorização e desvalorização por setores da sociedade e como efeito do processo de formação da atual sociedade moderna. Analisa a situação socioeconômica dos jovens dessa comunidade como um dos diversos fatores integrantes para a composição desta vulnerabilidade. Avalia ainda as políticas de prevenção, controle e tratamento as DST/AIDS neste segmento populacional. Optou-se pela abordagem quantitativa do tipo survey, utilizando como instrumento de coleta de dados um formulário de perguntas fechadas a 50 jovens da comunidade, situados na faixa etária de 18 a 24 anos. Dentre os resultados, destacam-se: a baixa escolaridade, desemprego e renda familiar inferior a 1 salário mínimo, impossibilitando o acesso dos jovens aos meios de proteção e prevenção às DST/AIDS; a maioria dos jovens não percebe o risco às DST/AIDS que estão expostos; evidenciou-se comportamentos de riscos adotados pelos jovens, como desuso de preservativos nas relações sexuais e uso de drogas injetáveis.
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Gonçalves, Agnaldo de Souza [UNESP]. "Células solares de ZnO:Ga nanocristalino sensibilizado por corante." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/105779.
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goncalves_as_dr_araiq.pdf: 8384691 bytes, checksum: 99f915f60f4aa419101cf4839adc9f92 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Com o objetivo de melhorar o transporte eletrônico no eletrodo nanoestruturado de ZnO, íons Ga3+ foram utilizados neste trabalho como dopantes e/ou modificadores da superfície. Nanopartículas de ZnO e ZnO:Ga 1, 3 e 5% cristalinas foram preparadas pelo método da precipitação a baixa temperatura. Nenhuma evidência da formação de ZnGa2O4, mesmo na amostra ZnO:Ga 5%, foi detectada por DRX. Dados de XPS revelaram que Ga está presente na matriz de ZnO como Ga3+. O tamanho de partícula diminuiu com o aumento na quantidade de gálio, como observado por FE-SEM, provavelmente devido a uma velocidade de hidrólise mais rápida. O menor tamanho de partícula proporcionou filmes com maior porosidade e área superficial, possibilitando uma maior quantidade de corante adsorvida. Quando estes filmes foram aplicados em células solares, o dispositivo baseado em ZnO:Ga 5% apresentou eficiência global na conversão de energia de 6% (a 10 mW cm-2), um valor três vezes maior que o observado para as células solares de ZnO neste trabalho. Este é um dos maiores valores já relatados para células solares de ZnO. Estudos por TAS da dinâmica fotoinduzida em filmes de ZnO:Ga sensibilizados revelaram um maior rendimento do cátion do corante com o aumento na quantidade de gálio, além de uma aceleração no processo de recombinação de carga. Este estudo indica que a dopagem de ZnO com íons Ga3+ possibilita um aumento na fotocorrente e eficiência global do dispositivo. O coeficiente de difusão (D) e o tempo de vida do elétron (τ) foram estudados em células solares seladas por SLIM-PCV. Em comparação às células solares de ZnO, menores valores de D e maiores valores de τ foram observados nas células solares de ZnO:Ga. O mesmo comportamento foi também observado por EIS. Em condições de densidade eletrônica equivalente, os menores valores de Voc em células solares de ZnO:Ga comparados...
In order to enhance the electron transport properties in the ZnO nanostructured electrode, Ga3+ was used in this work as the impurity ions as either surface modifiers and/or dopants. Highly crystalline ZnO and Ga-modified zinc oxide (ZnO:Ga) nanoparticles containing 1, 3, and 5 at.% of Ga3+ were prepared by the precipitation method at low temperature. No evidence of ZnGa2O4, even in the samples containing 5 at.% of Ga3+, was detected by XRD. XPS data revealed that Ga is present into the ZnO matrix as Ga3+. The particle size decreased as the gallium concentration was raised as observed by SEM, which might be related to a faster hydrolysis reaction rate. The smaller particle size provided films with higher porosity and surface area, enabling a higher dye loading. When these films were applied to DSSCs as photoelectrodes, the device based on ZnO:Ga 5 at.% presented an overall conversion efficiency of 6% (at 10 mW cm-2), a three-fold increase compared to the ZnObased DSSCs under the same condition. This is one of the highest efficiencies reported so far for ZnO-based DSSCs. The transient absorption (TAS) study of the photoinduced dynamics of dye-sensitized ZnO:Ga films showed the higher the gallium content, the higher the amount of dye cation formed, while a faster recombination dynamics was observed. The study indicates that Ga-modification of nanocrystalline ZnO leads to an improvement of photocurrent and overall efficiency in the corresponding device. The diffusion coefficient (D) and electron lifetime (τ) were studied in sealed DSSCs by SLIM-PCV. In comparison to the DSSCs based on ZnO electrodes, the ZnO:Ga-based cells provided lower D values and higher values of τ. The result was interpreted with transport limited recombination. The same behavior was also observed by EIS. At matched electron densities, a lower open-circuit voltage (Voc) of DSSCs based on ZnO:Ga was observed... (Complete abstract click electronic access below)
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Delices, Annette. "Organized Organic Dye / Hole Transporting Materials for TiO2- and ZnO- based Solid-State Dye-Sensitized Solar Cells (s-DSSCs)." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC066/document.
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En raison des problèmes d'instabilité à moyen termes des cellules solaires à colorant (DSSC), l'électrolyte liquide à base d'iodure a été remplacé par plusieurs types de matériaux solides transport de trous (HTM) pour obtenir des DSSCs à l'état solide (s-DSSCs). Parmi ces matériaux, l’utilisation des polymères conducteurs(PC) a attiré une attention considérable en raison de leur bonne stabilité, de leur haute conductivité et de la facilité de leur dépôt sur le semi-conducteur mésoporeux TiO2. Dans ce travail de thèse, plusieurs s-DSSCs basées sur des PC utilisés comme HTM ont été développés dans le but d'améliorer leurs performances photovoltaïques en tenant compte des deux objectifs suivants: (i) l'optimisation des processus de transfert inter facial de charge dans la cellule solaire, et (ii) l'optimisation du transport de charge dans le semi-conducteur d'oxyde de type n. Pour atteindre ces objectifs, chaque composant de la s-DSSC a été modifié afin d'étudier son effet sur les performances du dispositif final. En première tentative, une étude analytique est réalisée en faisant varier le sensibilisateur afin de déterminer les fragments de la structure du colorant, qui ont un effet important sur le processus de photopolymérization électrochimique in-situ (PEP) à la fois en milieu organique et en milieu aqueux mais aussi sur les performances des s-DSSCs. Sur la base de ces résultats, un nouveau concept a été développé et consiste en la suppression totale de l'interface entre le colorant et le HTM. Ceci est obtenu par la synthèse de nouveaux colorants liés de façon covalente à un monomère électroactif qui est co-polymérisé par la PEP in-situ. Le copolymère résultant, utilisé comme HTM, est lié de manière covalente au colorant. En outre, la nature de la liaison chimique, reliant le résidu triphénylamine TPA au monomère, est également étudiée comme un facteur clé dans les performances de s-DSSC. En outre, et pour optimiser les processus de transport de charges dans ce type de s-DSSC, de nouvelles s-DSSC basées sur ZnO ont été réalisées et étudiéesDue to instability problems of dye sensitized solar cells (DSSCs) in longtime uses, the iodine based liquidelectrolyte has been replaced by several types of solid hole transporting materials (HTM) to perform solidstate DSSCs (s-DSSCs). Among them, the substitution by conducting polymers (CP) has attractedconsiderable attention because of their good stability, high hole-conductivity and simple deposition withinthe mesoporous TiO2 semiconductor. In this thesis work, several s-DSSCs based on CPs used as HTM havebeen developed in order to improve their photovoltaic performances taking into account the following twoobjectives: (i) the optimization of the interfacial charge transfer processes within the solar cell, and (ii) theoptimization of the charge transport within the n-type oxide semiconductor. To reach these goals, eachcomponent that constitutes the device was varied in order to investigate its effect on the device’sperformances. As first attempt, an analytical study is carried out by varying the sensitizer in order todetermine the fragments of the dyes structures, that have an important effect on the in-situ photoelectrochemical polymerization process (PEP) both in organic and in aqueous media and hence on theperformances of the s-DSSCs. Based on these results, a new concept of removing completely the interfacebetween the dye and the HTM is developed. This is achieved by the synthesis of new dyes covalently linkedto an electroactive monomer which is co-polymerized by in-situ PEP. The resulting co-polymer, used asHTM, is covalently linked to the dye. In addition, the nature of the chemical bond linking the triphenylamineresidue TPA to the monomer is also investigated as a key factor in the s-DSSCs performances. Besides, andto optimize the charge transport processes within this type of s-DSSC, the elaboration of novel ZnO baseds-DSSCs has been achieved and investigated
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Wang, Bo. "SOLID STATE AND LIQUID STATE NANOCRYSTALLINE SOLAR CELLS ON RIGID AND FLEXIBLE SUBSTRATES." Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1281658251.
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Holst, Bruna. "Evidências de validade da escala de clima escolar Delaware School Climate Survey-Student (DSCS-S) no Brasil." Pontifícia Universidade Católica do Rio Grande do Sul, 2014. http://hdl.handle.net/10923/7017.
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Previous issue date: 2014Introduction: School climate refers to the quality of school life and it is based on patterns of people's experiences in school, and involves norms, goals, values, interpersonal relationships, teaching and learning practices and institutional structures. Poor school climate has been associated with learning disabilities, school drop out, substance abuse, non-compliance of school rules, depression, low self-esteem and bullying in previous studies. However, there are no validated instruments to assess school climate in Brazil. The Delaware School Climate Survey-Student (DSCS-S) is an instrument composed by 78 items, divided into: Scale I - School Climate; Scale II - School Techniques; Scale III - Bullying and Cyberbullying Victimization; and Scale IV - Cognitive, Behavioral and Emotional Student Engagement. Objective: This study aims to investigate evidences of validity of this survey in Brazil, as well as investigate associations of school climate dimensions with characteristics of schools and students in Southern Brazil. Method: This dissertation comprised three manuscripts. The first describes the cross-cultural adaptation and the search for evidence of content validity of the DSCS-S. The second describes the investigation of the psychometric properties of the DSCS-S, more specifically the evidence of construct validity through exploratory and confirmatory factor analysis. The third discusses how the DSCS-S dimensions correlated with each other and how they associated with characteristics of Brazilian students. The sample consisted in 436 students, aged from 9 to 18 years old (M = 12. 98, SD = 1. 80; 51. 8% girls), from 2 private schools (50. 5% of the students assessed) and four public schools located in the cities of Porto Alegre, Gramado and Viamão (Rio Grande do Sul state, Brazil). The DSCS-S and a demographic data questionnaire developed for this study were applied. Procedures for a cross-cultural adaptation were adopted and also evidences of validity of the instrument were investigated along with correlations between the DSCS-S dimensions and student characteristics such as age, gender, number, occurrence of repetition and type of education (private or public).Results: The cross-cultural adaptation resulted in a Portuguese version that is consistent and showed evidence of content validity and proper congruence between the expert committee. Confirmatory factor analysis showed more acceptable fit indices than the exploratory factor analysis. Results indicate (1) the importance of follow a rigorous crosscultural adaptation method to ensure instruments’ content validity; (2) that the Portuguese version of the DSCS-S showed evidences of content and construct validity; and (3) that school strategies to promote a positive climate should focus on student engagement and the development of social-emotional learning school techniques. Conclusion: The DSCS-S can attend Brazilian schools’ demand for climate assessments and support the development of more assertive education policies and strategies that will foster a positive school climate.
Introdução: O clima escolar refere-se à qualidade da vida escolar e está baseado no padrão de experiências das pessoas na escola, envolvendo normas, metas, valores, relacionamentos interpessoais, práticas de ensino e aprendizado e estruturas institucionais. Climas escolares negativos, a partir de estudos prévios, foram associado a dificuldades de aprendizagem, evasão escolar, uso de substâncias psicoativas, desacato a regras escolares, sintomas de depressão, baixa autoestima e bullying. Entretanto, não existem instrumentos validados para avaliação de clima escolar no Brasil. O Delaware School Climate Survey-Sudent (DSCS-S) é um instrumento composto por 78 itens, divididos em: Escala I - Clima Escolar; Escala II - Técnicas Escolares; Escala III - Vitimização no bullying e cyberbullying; Escala IV - Engajamento Estudantil cognitivo, comportamental e emocional. Objetivo: Este estudo objetiva investigar evidências de validade deste instrumento no Brasil, assim como investigar associações das dimensões do clima escolar com características de escolas e alunos do sul do Brasil.Método: Esta dissertação é composta por três manuscritos. O primeiro descreve a adaptação transcultural e a investigação de evidências de validade de conteúdo do DSCS-S. O segundo descreve a investigação das propriedades psicométricas do instrumento, mais especificadamente das evidências de validade de construto do DSCS-S mediante análise fatorial confirmatória e exploratória. O terceiro aborda como as dimensões do DSCS-S correlacionam entre si e se associam com características dos alunos brasileiros. Participaram da pesquisa 436 alunos (51,8% meninas) de 9 a 18 anos (M = 12,98; DP = 1,80), de 2 escolas privadas (50,5% dos alunos avaliados) e 4 escolas públicas de Porto Alegre, Gramado e Viamão/RS. Foram aplicados o DSCS-S e um questionário de dados sociodemográficos elaborado para esta pesquisa. Foram adotados procedimentos para a adaptação transcultural, investigadas evidências de validade do instrumento e também correlações entre as dimensões do DSCS-S e características dos alunos como idade, gênero, série, ocorrência de repetência e modalidade de ensino (privado ou público).Resultados: A adaptação transcultural originou uma versão em português que é consistente e apresenta validade de conteúdo, assim como foi observada adequada congruência entre juízes. As análises fatoriais confirmatórias apresentaram índices de ajuste mais aceitáveis do que as exploratórias. Resultados indicam (1) a importância de um rigoroso método de adaptação transcultural de instrumentos para garantir a validade de conteúdo; (2) a existência de evidências de validade de conteúdo e de construto do DSCS-S para a língua portuguesa do Brasil; e (3) que estratégias para promover um clima escolar positivo devem focar no engajamento dos alunos e no desenvolvimento de técnicas escolares focadas no aprendizado sócio-emocional. Conclusão: O instrumento DSCS-S pode atender a demanda das escolas brasileiras por avaliações de seu clima e auxiliar no desenvolvimento de políticas de educação e na concepção de estratégias e programas escolares mais assertivos e que promovam o clima escolar positivo.
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Oltramari, Leandro Castro. "Representações sociais de profissionais do sexo da Região Metropolitana de Florianópolis sobre prevenção da AIDS E DSTs." Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/79987.
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Dissertação(mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-Graduação em PsicologiaMade available in DSpace on 2012-10-18T09:22:20Z (GMT). No. of bitstreams: 0Bitstream added on 2014-09-25T20:40:34Z : No. of bitstreams: 1 182358.pdf: 3117330 bytes, checksum: f39061069c4d155c693d05df98aa7d9d (MD5)
O presente estudo refere-se às representações sociais de mulheres profissionais do sexo sobre a AIDS, a prevenção das doenças sexualmente transmissíveis (DSTs) e a contracepção. As mulheres têm-se mostrado capazes de adotar comportamentos preventivos frente a estas doenças, através do uso de preservativo com seus clientes.. Portanto, entendemos ser necessário estudar as representações sociais das profissionais do sexo sobre a AIDS, a prevenção das DSTs e contracepção. Foram entrevistadas 40 mulheres (com idade mínima de 19 anos e máxima de 47 anos). Das entrevistadas, 18 delas tinham relações estáveis, não comerciais, com parceiro fixo e 22 não tinham parceiro fixo no momento da entrevista. Para a análise do material coletado, foi utilizado um software de análise quantitativa de dados textuais (ALCESTE). Os resultados demonstraram que as representações sociais da AIDS, prevenção das DSTs e da gravidez, compartilhadas pelas profissionais do sexo, são diferentes, tratando-se de mulheres que têm uma vida sexual com um parceiro fixo. Neste caso, estas representações parecem incorporar menos o conhecimento preventivo (oriundo do universo especializado da prevenção de DSTs e da AIDS), o que pode significar, para estas mulheres, uma condição de maior vulnerabilidade diante da AIDS do que as outras. O risco parece estar onde elas acreditam estar seguras, ou seja, nas relações não comerciais. Outro resultado que chamou a atenção foi, para as entrevistadas, a relação existente entre AIDS e drogas; lícitas ( uso de bebida em boates) e ilícitas ( uso dos clientes). Estes fenômenos foram caracterizados pelas entrevistadas como facilitadores do risco de infecção pela AIDS.
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Gonçalves, Agnaldo de Souza. "Células solares de ZnO:Ga nanocristalino sensibilizado por corante /." Araraquara : [s.n.], 2008. http://hdl.handle.net/11449/105779.
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Orientador: Marian Rosaly DavolosCoorientador: Ana Flávia Nogueira
Banca: Luiz Antonio Andrade de Oliveira
Banca: Fernando Aparecido Sigoli
Banca: Ivo Alexandre Hummelgen
Banca: Koiti Araki
Resumo: Com o objetivo de melhorar o transporte eletrônico no eletrodo nanoestruturado de ZnO, íons Ga3+ foram utilizados neste trabalho como dopantes e/ou modificadores da superfície. Nanopartículas de ZnO e ZnO:Ga 1, 3 e 5% cristalinas foram preparadas pelo método da precipitação a baixa temperatura. Nenhuma evidência da formação de ZnGa2O4, mesmo na amostra ZnO:Ga 5%, foi detectada por DRX. Dados de XPS revelaram que Ga está presente na matriz de ZnO como Ga3+. O tamanho de partícula diminuiu com o aumento na quantidade de gálio, como observado por FE-SEM, provavelmente devido a uma velocidade de hidrólise mais rápida. O menor tamanho de partícula proporcionou filmes com maior porosidade e área superficial, possibilitando uma maior quantidade de corante adsorvida. Quando estes filmes foram aplicados em células solares, o dispositivo baseado em ZnO:Ga 5% apresentou eficiência global na conversão de energia de 6% (a 10 mW cm-2), um valor três vezes maior que o observado para as células solares de ZnO neste trabalho. Este é um dos maiores valores já relatados para células solares de ZnO. Estudos por TAS da dinâmica fotoinduzida em filmes de ZnO:Ga sensibilizados revelaram um maior rendimento do cátion do corante com o aumento na quantidade de gálio, além de uma aceleração no processo de recombinação de carga. Este estudo indica que a dopagem de ZnO com íons Ga3+ possibilita um aumento na fotocorrente e eficiência global do dispositivo. O coeficiente de difusão (D) e o tempo de vida do elétron (τ) foram estudados em células solares seladas por SLIM-PCV. Em comparação às células solares de ZnO, menores valores de D e maiores valores de τ foram observados nas células solares de ZnO:Ga. O mesmo comportamento foi também observado por EIS. Em condições de densidade eletrônica equivalente, os menores valores de Voc em células solares de ZnO:Ga comparados... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In order to enhance the electron transport properties in the ZnO nanostructured electrode, Ga3+ was used in this work as the impurity ions as either surface modifiers and/or dopants. Highly crystalline ZnO and Ga-modified zinc oxide (ZnO:Ga) nanoparticles containing 1, 3, and 5 at.% of Ga3+ were prepared by the precipitation method at low temperature. No evidence of ZnGa2O4, even in the samples containing 5 at.% of Ga3+, was detected by XRD. XPS data revealed that Ga is present into the ZnO matrix as Ga3+. The particle size decreased as the gallium concentration was raised as observed by SEM, which might be related to a faster hydrolysis reaction rate. The smaller particle size provided films with higher porosity and surface area, enabling a higher dye loading. When these films were applied to DSSCs as photoelectrodes, the device based on ZnO:Ga 5 at.% presented an overall conversion efficiency of 6% (at 10 mW cm-2), a three-fold increase compared to the ZnObased DSSCs under the same condition. This is one of the highest efficiencies reported so far for ZnO-based DSSCs. The transient absorption (TAS) study of the photoinduced dynamics of dye-sensitized ZnO:Ga films showed the higher the gallium content, the higher the amount of dye cation formed, while a faster recombination dynamics was observed. The study indicates that Ga-modification of nanocrystalline ZnO leads to an improvement of photocurrent and overall efficiency in the corresponding device. The diffusion coefficient (D) and electron lifetime (τ) were studied in sealed DSSCs by SLIM-PCV. In comparison to the DSSCs based on ZnO electrodes, the ZnO:Ga-based cells provided lower D values and higher values of τ. The result was interpreted with transport limited recombination. The same behavior was also observed by EIS. At matched electron densities, a lower open-circuit voltage (Voc) of DSSCs based on ZnO:Ga was observed... (Complete abstract click electronic access below)
Doutor
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Holst, Bruna. "Evid?ncias de validade da escala de clima escolar Delaware School Climate Survey-Student (DSCS-S) no Brasil." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2015. http://tede2.pucrs.br/tede2/handle/tede/897.
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Previous issue date: 2015-01-15Introduction: School climate refers to the quality of school life and it is based on patterns of people's experiences in school, and involves norms, goals, values, interpersonal relationships, teaching and learning practices and institutional structures. Poor school climate has been associated with learning disabilities, school drop out, substance abuse, non-compliance of school rules, depression, low self-esteem and bullying in previous studies. However, there are no validated instruments to assess school climate in Brazil. The Delaware School Climate Survey-Student (DSCS-S) is an instrument composed by 78 items, divided into: Scale I - School Climate; Scale II - School Techniques; Scale III - Bullying and Cyberbullying Victimization; and Scale IV - Cognitive, Behavioral and Emotional Student Engagement. Objective: This study aims to investigate evidences of validity of this survey in Brazil, as well as investigate associations of school climate dimensions with characteristics of schools and students in Southern Brazil. Method: This dissertation comprised three manuscripts. The first describes the cross-cultural adaptation and the search for evidence of content validity of the DSCS-S. The second describes the investigation of the psychometric properties of the DSCS-S, more specifically the evidence of construct validity through exploratory and confirmatory factor analysis. The third discusses how the DSCS-S dimensions correlated with each other and how they associated with characteristics of Brazilian students. The sample consisted in 436 students, aged from 9 to 18 years old (M = 12.98, SD = 1.80; 51.8% girls), from 2 private schools (50.5% of the students assessed) and four public schools located in the cities of Porto Alegre, Gramado and Viam?o (Rio Grande do Sul state, Brazil). The DSCS-S and a demographic data questionnaire developed for this study were applied. Procedures for a cross-cultural adaptation were adopted and also evidences of validity of the instrument were investigated along with correlations between the DSCS-S dimensions and student characteristics such as age, gender, number, occurrence of repetition and type of education (private or public). Results: The cross-cultural adaptation resulted in a Portuguese version that is consistent and showed evidence of content validity and proper congruence between the expert committee. Confirmatory factor analysis showed more acceptable fit indices than the exploratory factor analysis. Results indicate (1) the importance of follow a rigorous crosscultural adaptation method to ensure instruments content validity; (2) that the Portuguese version of the DSCS-S showed evidences of content and construct validity; and (3) that school strategies to promote a positive climate should focus on student engagement and the development of social-emotional learning school techniques. Conclusion: The DSCS-S can attend Brazilian schools demand for climate assessments and support the development of more assertive education policies and strategies that will foster a positive school climate.
Introdu??o: O clima escolar refere-se ? qualidade da vida escolar e est? baseado no padr?o de experi?ncias das pessoas na escola, envolvendo normas, metas, valores, relacionamentos interpessoais, pr?ticas de ensino e aprendizado e estruturas institucionais. Climas escolares negativos, a partir de estudos pr?vios, foram associado a dificuldades de aprendizagem, evas?o escolar, uso de subst?ncias psicoativas, desacato a regras escolares, sintomas de depress?o, baixa autoestima e bullying. Entretanto, n?o existem instrumentos validados para avalia??o de clima escolar no Brasil. O Delaware School Climate Survey-Sudent (DSCS-S) ? um instrumento composto por 78 itens, divididos em: Escala I - Clima Escolar; Escala II - T?cnicas Escolares; Escala III - Vitimiza??o no bullying e cyberbullying; Escala IV - Engajamento Estudantil cognitivo, comportamental e emocional. Objetivo: Este estudo objetiva investigar evid?ncias de validade deste instrumento no Brasil, assim como investigar associa??es das dimens?es do clima escolar com caracter?sticas de escolas e alunos do sul do Brasil. M?todo: Esta disserta??o ? composta por tr?s manuscritos. O primeiro descreve a adapta??o transcultural e a investiga??o de evid?ncias de validade de conte?do do DSCS-S. O segundo descreve a investiga??o das propriedades psicom?tricas do instrumento, mais especificadamente das evid?ncias de validade de construto do DSCS-S mediante an?lise fatorial confirmat?ria e explorat?ria. O terceiro aborda como as dimens?es do DSCS-S correlacionam entre si e se associam com caracter?sticas dos alunos brasileiros. Participaram da pesquisa 436 alunos (51,8% meninas) de 9 a 18 anos (M = 12,98; DP = 1,80), de 2 escolas privadas (50,5% dos alunos avaliados) e 4 escolas p?blicas de Porto Alegre, Gramado e Viam?o/RS. Foram aplicados o DSCS-S e um question?rio de dados sociodemogr?ficos elaborado para esta pesquisa. Foram adotados procedimentos para a adapta??o transcultural, investigadas evid?ncias de validade do instrumento e tamb?m correla??es entre as dimens?es do DSCS-S e caracter?sticas dos alunos como idade, g?nero, s?rie, ocorr?ncia de repet?ncia e modalidade de ensino (privado ou p?blico). Resultados: A adapta??o transcultural originou uma vers?o em portugu?s que ? consistente e apresenta validade de conte?do, assim como foi observada adequada congru?ncia entre ju?zes. As an?lises fatoriais confirmat?rias apresentaram ?ndices de ajuste mais aceit?veis do que as explorat?rias. Resultados indicam (1) a import?ncia de um rigoroso m?todo de adapta??o transcultural de instrumentos para garantir a validade de conte?do; (2) a exist?ncia de evid?ncias de validade de conte?do e de construto do DSCS-S para a l?ngua portuguesa do Brasil; e (3) que estrat?gias para promover um clima escolar positivo devem focar no engajamento dos alunos e no desenvolvimento de t?cnicas escolares focadas no aprendizado s?cio-emocional. Conclus?o: O instrumento DSCS-S pode atender a demanda das escolas brasileiras por avalia??es de seu clima e auxiliar no desenvolvimento de pol?ticas de educa??o e na concep??o de estrat?gias e programas escolares mais assertivos e que promovam o clima escolar positivo.
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Paula, Leonardo Ferreira de. "Síntese e caracterização de filmes de óxidos metálicos nanoparticulados para aplicação em células solares sensibilizadas por corante (DSCs)." Universidade Federal de Uberlândia, 2014. https://repositorio.ufu.br/handle/123456789/17410.
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In this work, thin and compact films of TiO2, Nb2O5 and WO3 nanoparticles were prepared to be used as contact/blocking layer in dye sensitized solar cells (DSCs). The films were produced by deposition of 30 bilayers of TiO2(ac)/TiO2(bas), TiO2(ac)/Nb2O5(bas) and TiO2(ac)/WO3(bas) using the layer-by-layer technique (LbL) from nanoparticle sols of TiO2 (pH = 2 and 10), Nb2O5 (pH = 10) and WO3 (pH 10) prepared by sol-gel method. The TiO2/TiO2 and TiO2/Nb2O5 underlayers resulted in an increase of 25% and 87% respectively, in the efficiency of DSCs when compared to those without the contact/blocking layers. The application of TiO2/WO3 films did not result in any improvement of DSC efficiency. Factors such as thickness, nanoparticles homogeneity, oxides concentration on the films and roughness directly influence on the efficiency of such films as contact/blocking layer. Field Emission Scanning Electron Microscopy (FESEM) and Atomic Force Microscopy (AFM) images, confirmed that all films are constituted by spherical nanoparticles with homogeneous diameters smaller than 20 nm, resulting on compact and low porous surfaces. This morphology ensures a physical barrier between the electrolyte and the conductive glass used as electrode in DSCs. The TiO2/TiO2 and TiO2/Nb2O5 films also exhibited higher roughness than the surface of the conductive glass without the bilayers, which increases the interaction with the mesoporous TiO2 film. The molar ratios of the species present on the films are controlled by the pH employed during deposition, and were determined by X- ray photoelectron spectroscopy (XPS). The Ti4+/Nb5+ and Ti4+/W6+ ratios were 1.6 and 19 respectively, which evidences a higher concentration of TiO2 nanoparticles on the films. For a better understanding of the role of the bilayers on the charge transfer processes, the substrates were analyzed by Electrochemical Impedance Spectroscopy (EIS). The electronic properties of the oxides also influence the efficiency of the LbL films as contact/blocking layers. Due to its higher band gap, Nb2O5 nanoparticles impose an electronic barrier to the electrons transfer from the conductive substrate to the electrolyte, additionally to the physical barrier.Neste trabalho foram preparados filmes finos e compactos de óxidos nanoparticulados de TiO2, Nb2O5 e WO3 para a aplicação como camada de contato/bloqueio em células solares sensibilizadas por corante (DSCs). Os filmes foram produzidos pela deposição de 30 bicamadas de TiO2(ác)/TiO2(bás), TiO2(ác/Nb2O5(bás) e TiO2(ác)/WO3(bás) utilizando a técnica de automontagem (Layer-by-Layer ou LbL), a partir dos sóis nanoparticulados de TiO2 (pH = 2 e 10), Nb2O5 (pH = 10) e WO3 (pH = 10) sintetizados pelo método sol-gel. A presença das bicamadas de TiO2/TiO2, TiO2/Nb2O5 gerou aumentos relativos na eficiência das DSCs de 25% e 87% respectivamente, quando comparadas às DSCs sem as bicamadas. Já o filme de TiO2/WO3 não gerou nenhuma melhoria na eficiência das DSCs. Fatores como a espessura, homogeneidade das nanopartículas, concentração dos óxidos nos filmes e a rugosidade influenciam diretamente na eficiência dos filmes como camada de contato/bloqueio. Imagens de Microscopia Eletrônica de Varredura com Emissão de Campo (MEV-FEG) e Microscopia de Força Atômica (MFA) confirmaram que todos os filmes apresentaram nanopartículas esféricas com diâmetros homogêneos e menores que 20 nm, o que acarreta na formação de superfícies compactas e pouco porosas. Esta morfologia garante uma barreira física entre o eletrólito e a superfície do vidro condutor utilizado como eletrodo nas DSCs. Os filmes de TiO2/TiO2 e TiO2/Nb2O5 apresentaram também rugosidades maiores que a da superfície do vidro condutor sem as bicamadas, o que aumenta a interação entre com o filme de TiO2 mesoporoso. As razões molares das espécies presentes nos filmes são controladas pelo pH empregado durante as deposições, e foram determinadas por Espectroscopia de Fotoelétrons Excitados por raios-X (XPS). As razões Ti4+/Nb5+ e Ti4+/W6+ foram de 1,6 e 19 respectivamente, o que evidencia uma maior quantidade de nanopartículas de TiO2 nos filmes. Para melhor entender o papel das bicamadas nos processos de transferência de cargas, os substratos foram analisados por Espectroscopia de Impedância Eletroquímica (EIE). As propriedades eletrônicas dos óxidos também influenciam na eficiência dos filmes automontados como camada de contato/bloqueio. Devido ao seu maior valor de band gap, as nanopartículas de Nb2O5 impõem, além de uma barreira física, uma barreira eletrônica para a transferência dos elétrons do substrato condutor para o eletrólito.
Mestre em Química
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Camaratta, Rubens. "Synthesis Of ZnO and TiO2 By Biomimetization Of Eggshell Membranes And Its Evaluation As Anode In Dye-Sensitized Solar Cells." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/113416.
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Esta tesis presenta un conjunto original de procedimientos para la síntesis de nanoestructuras de TiO2 y ZnO por biomimetización de membranas de cáscara de huevo obteniendo materiales valiosos para fotovoltaica como se muestra en su evaluación de rendimiento como ánodo en células solares sensibilizadas por colorante. "El manuscrito está dividido en 7 capítulos.
En el primer capítulo, titulado Introducción, se presentan las bases teóricas para la comprensión de los procesos de biomimetización, membranas de cáscara de huevo, síntesis de ZnO y TiO2, y células solares sensibilizadas por colorantes (DSSC). Después del capítulo introductorio, el Capítulo 2 revela los objetivos generales y específicos de esta investigación. Posteriormente, el Capítulo 3 describe el procedimiento experimental utilizado para las síntesis y caracterizaciones de ZnO y TiO2, así como el procedimiento utilizado en el ensamblaje y la caracterización de las células fotovoltaicas.
En el capítulo 4 se presentan y discuten los resultados obtenidos con las síntesis y la aplicación de los polvos como fotodoles en DSSC. En este capítulo, hemos decidido subdividirlo en secciones específicas para explicar cuestiones científicas específicas sobre el tema.
En el capítulo 5 se presentan las conclusiones del estudio en vista de los diferentes aspectos: obtención de TiO2 biomimético y ZnO, diferencias entre los polvos sintetizados por biomimetización de las membranas de cáscara de huevo, y la caracterización de las células construidas con los polvos biomiméticos.Esta tesi presenta un conjunt original de procediments per a la síntesi de nanoestructuras de TiO2 i ZnO per biomimetización de membranes de corfa d'ou obtenint materials valuosos per a fotovoltaica com es mostra en la seua avaluació de rendiment com a ànode en cèl·lules solars sensibilitzades per colorant. "El manuscrit està dividit en 7 capítols. En el primer capítol, titulat Introducció, es presenten les bases teòriques per a la comprensió dels processos de biomimetización, membranes de corfa d'ou, síntesi de ZnO i TiO2, i cèl·lules solars sensibilitzades per colorants (DSSC) . Després del capítol introductori, el Capítol 2 revela els objectius generals i específics d'esta investigació. Posteriorment, el Capítol 3 descriu el procediment experimental utilitzat per a les síntesis i caracteritzacions de ZnO i TiO2, així com el procediment utilitzat en l'acoblament i la caracterització de les cèl·lules fotovoltaiques. En el capítol 4 es presenten i discutixen els resultats obtinguts amb les síntesis i l'aplicació de les pols com fotodoles en DSSC. En este capítol, hem decidit subdividir-ho en seccions específiques per a explicar qüestions científiques específiques sobre el tema. En el capítol 5 es presenten les conclusions de l'estudi en vista dels diferents aspectes: obtenció de TiO2 biomimético i ZnO, diferències entre les pols sintetitzats per biomimetización de les membranes de corfa d'ou, i la caracterització de les cèl·lules construïdes amb les pols biomiméticos.
This thesis introduces an original set of procedures for the Synthesis of ZnO and TiO2 nanostructures by biomimetization of eggshell membranes obtaining valuable materiales for photovoltaic as shown on their performance evaluation as anode in Dye-Sensitized Solar Cells". The manuscript is divided into 7 chapters. In the first chapter, entitled Introduction, it is presented the theoretical bases for the understanding of the biomimetization processes, eggshell membranes, ZnO and TiO2 syntheses, and dye-sensitized solar cells (DSSC). After the introductory chapter, Chapter 2 reveals the general and specific objectives of this research. Subsequently, Chapter 3 describes the experimental procedure used for the syntheses and characterizations of ZnO and TiO2 as well as the procedure used in the assembly and characterization of the photovoltaic cells. In chapter 4 are presented and discussed the results obtained with the syntheses and application of the powders as photoanodes in DSSC. In this chapter, we have chosen to subdivide it into specific sections to explain specific scientific issues on the subject. In chapter 5 the conclusions of the study are presented in view of the different aspects: obtaining ZnO and biomimetic TiO2, differences between the powders synthesized by biomimetization of eggshell membranes, and the characterization of the cells constructed with the biomimetic powders.
Camaratta, R. (2018). Synthesis Of ZnO and TiO2 By Biomimetization Of Eggshell Membranes And Its Evaluation As Anode In Dye-Sensitized Solar Cells [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/113416
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Camaratta, Rubens. "Síntese do ZnO por biomimetização de membranas de cascas de ovos, e sua comparação com TiO2, para aplicação como ânodo em células fotovoltaicas sensibilizadas por corante." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/87345.
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Esta tese de doutorado versou sobre a obtenção e caracterização do semicondutor ZnO obtido por biomimetização de membranas da cascas de ovos (MCOs) e a sua aplicação como coletor fotovoltaico do tipo sensibilizado por corante. Na síntese do ZnO, as MCOs foram submergidas em uma solução contendo os íons precursores de Zn. As membranas atuaram como um biotemplate, servindo como base para que o ZnO tivesse sua nucleação e crescimento na forma de nanocristais. Foram investigados dois diferentes precursores de Zn (nitrato de zinco hexahidratado e acetato de zinco dihidratado) e verificou-se a influência do tratamento térmico na formação do ZnO. Os materiais obtidos foram caracterizados quanto à sua morfologia, área superficial, porosidade e propriedades óticas em função do tratamento térmico praticado. Para efeito de comparação, foi obtido TiO2 por biomimetização de cascas de ovos, além de ZnO por processo de precipitação. As amostras que foram preparadas utilizando o biotemplate apresentaram como características, pequeno tamanho de domínio cristalino e larga área superficial em comparação com as amostras de ZnO preparadas por precipitação. As propriedades óticas e cristalinidade apresentadas pelo ZnO obtido por biomimetização são comparáveis às da fase anatase do TiO2 e portanto compatíveis com a aplicação em células fotovoltaicas sensibilizadas por corante (DSSC – Dye sensitized solar cells). Para a formação de um filme fino e poroso, o ZnO obtido pela biomimetização das MCOs foi então depositado pela técnica de screen printing sobre um substrato cerâmico preparado para servir como uma cerâmica solar baseada nas DSSCs. A preparação da base de uma DSSC sobre uma placa cerâmica foi possível pela deposição de uma camada metálica, produzida por aspersão térmica sobre o substrato cerâmico, e pela deposição de uma fina camada de ZnO por serigrafia. A aspersão térmica se mostrou uma técnica eficiente, obtendo uma boa ancoragem do metal aspergido sobre o substrato cerâmico esmaltado, demonstrado por análise EDS que ocorre difusão do metal depositado na camada esmaltada significando inclusive uma ancoragem química. A deposição por serigrafia da camada de ZnO porosa mostrou-se um método simples e barato obtendo-se camadas com morfologia razoável para a aplicação em DSSCs. Um melhor controle do tamanho dos poros pode ser obtido, otimizando-se ainda mais a pasta e a calcinação da peça.This doctoral thesis dealt about the obtaining and characterization of ZnO semiconductor obtained by biomimetization of eggshell membranes (ESMs) and its application as photovoltaic collector in dye sensitized solar cells (DSSCs). In the synthesis of ZnO, the ESMs were submerged in a solution containing the precursor ions of Zn. The membranes acted as a biotemplate, serving as basis for the ZnO had their nucleation and growth in the form of nanocrystals. We investigated two different precursors of Zn (zinc nitrate hexahydrate and zinc acetate dihydrate) and verified the influence of thermal treatment on the formation of ZnO. The materials were characterized according to their morphology, surface area, porosity and optical properties, as a function of the thermal treatment practiced. For comparison, TiO2 was obtained by biomimetization of ESM, and ZnO by precipitation process. The samples that were prepared using the biotemplate presented as characteristics small crystallite size and large surface area in comparison to the samples prepared by precipitation of ZnO. The optical properties and crystallinity presented by ZnO obtained by biomimetization are comparable to those of anatase phase of TiO2 and therefore compatible with the application in dye-sensitized solar cells (DSSC - Dye sensitized solar cells). ZnO obtained by biomimetization of ESMs was then used with the screen printing technique to form a thin porous film on a ceramic substrate, prepared to serve as a solar ceramic based on DSSCs. The preparation of a DSSC basis on a ceramic substrate was possible by the deposition of a metal layer by thermal spray on the ceramic substrate, and the deposition of a thin layer of ZnO by screen printing. The thermal spray proved to be an effective technique, getting a good anchoring of the metal sprayed on the glazed ceramic substrate, demonstrated byEDS analysis that diffusion occurs of the metal into the glazed ceramic substrate meaning chemical anchoring. The deposition by screen printing of the porous ZnO layer has shown to be a simple and inexpensive method yielding layers with reasonable morphology for use in DSSCs. A better control of pore size can be obtained by optimizing even more the paste and calcination of the samples.
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Araujo, Matias Monçalves. "Novos corantes moleculares derivados de sulfetos vinílicos: síntese e propriedades fotofísicas." Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/12761.
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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPqThis thesis describes, initially, the synthesis and photophysical characterization of new sulfides,sulphoxides and vinyl sulfones based dyes. The compounds in question were obtained in good yields and good diastereoselectivity through Horner-Wadsworth- Emmons (HWE) reactions. The compounds absorb light in the UV/Vis region, with the major transitions occurring between – * orbitals. As for the emission, the PS-1 and PS- 2 vinyl sulphides have their maximum emission bands in the blue region of the spectrum. The oxidation to their respective sulphoxides and sulfones, and the attainment of D– –A structure, causes the emission to undergo a bathochromic shift to the green region of the spectrum. These effects are most pronounced in the triphenylamine derivatives (PSO-1 and PSO2-1) and in polar solvents (positive solvatocromism). With the aid of DFT and TD-DFT calculations, it can be observed that this behaviors are related to the formation of intramolecular charge transfer states (ICT) in the excited state. Subsequently, the design, synthesis and characterization of new vinyl sulphides for possible application in dye-sensitized solar cell (DSSCs) are presented. The compounds were designed to have a D– –A structure, where the sulphides would serve as a bridge between the donor (D) and acceptor (A) blocks. The compounds studied were obtained by the HWE and Knoevenagel condensation, in good yields and good diastereoselectivity. Through preliminary photophysical analysis, it has been observed that the dyes have a wide light absorption range (250–550 nm), in particular the dyes derived from malononitrile PCN-1, PCN-2 and PSCN. In addition to being greatly influenced by the nature of the electron acceptor group. These characteristics are in line with that expected for application in DSSCs and are similar to several sensitizing dyes reported in the literature.
Nesta tese descreve-se, inicialmente, a síntese e a caracterização fotofísica de novos corantes derivados de sulfetos, sulfóxidos e sulfonas vinílicas. Os compostos em questão foram obtidos em bons rendimentos e boa diastereosseletividade, através de reações de Horner-Wadsworth-Emmons (HWE). As propriedades fotofísicas dos corantes estudados mostraram-se bastante interessantes. Os compostos absorvem luz na região do UV/Vis, sendo que as principais transições ocorrem entre orbitais – *. Quanto a emissão, os sulfetos vinílicos PS-1 e PS-2 têm suas bandas máximas de emissão na região azul do espectro. A oxidação para seus respectivos sulfóxidos e sulfonas, e a obtenção de estrutura do tipo D– –A, faz com que a emissão sofra um deslocamento batocrômico para a região verde do espectro. Estes efeitos são mais acentuados nos derivados da trifenilamina (PSO-1 e PSO2-1) e em solvente polares (solvatocromismo positivo). Com o auxílio de cálculos DFT e TD-DFT, pode-se constatar que estes comportamentos estão relacionados à formação de estados de transferência de carga intramolecular (ICT) no estado excitado. Posteriormente, são apresentados o design, síntese e caracterização de novos sulfetos vinílicos para possível aplicação em células solares sensibilizadas (DSSCs). Os compostos foram desenhados para possuírem estrutura do D– –A, onde os sulfetos vinílicos serviriam como uma “ponte” -conjugada para os blocos doador (D) e aceptor (A). Os compostos estudados foram obtidos através da reação de HWE e condensação de Knoevenagel, em bons rendimentos e boa diastereosseletividade. Através da análise fotofísica preliminar, observou-se que os corantes possuem uma ampla faixa de absorção de luz (250– 550 nm), sobretudo os corantes derivados da malononitrila PCN-1, PCN-2 e PSCN. Além de serem bastante influenciados pela natureza do grupo aceptor de elétrons. Estas características estão de acordo com o esperado para aplicação em DSSCs e, são semelhantes a diversos corantes sensibilizadores reportados na literatura.
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Cerqueira, Ana Filipa Reis. "Macrociclos tetrapirrólicos para células solares." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14180.
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Mestrado em Química - Química Orgânica e Produtos NaturaisA presente dissertação teve como principal objetivo sintetizar novos derivados porfirínicos com potencial aplicação em células solares sensibilizadas por corante (DSSCs) recorrendo a reações de acoplamento catalisadas por paládio em condições de Buchwald e a reações de ciclização oxidativa. O presente documento encontra-se dividido em três partes. Na primeira parte, descrevem-se as caraterísticas gerais das porfirinas bem como as suas propriedades espetroscópicas, métodos de preparação e funcionalização de posições β-pirrólicas, nomeadamente via reações catalisadas por paládio. Neste capítulo também serão abordados alguns trabalhos relacionados com a potencialidade de porfirinas como corantes em DSSCs. Na segunda parte, descreve-se a preparação de 2-(4-carboxiaminofenil)porfirinas formadas através do acoplamento catalisado por paládio entre (2-amino-5,10,15,20-tetrafenilporfirinato)níquel(II) e 4-iodobenzoato de metilo, seguido da hidrólise da função éster. A posterior reação de ciclização oxidativa redundou na formação de N-(4-carboxifenil)quinolino[2,3,4-at]porfirinas, moléculas comportando anéis fundidos. A extensão destas metodologias ao 5-bromoisoftalato de dimetilo resultou na obtenção de 2-(3,5-dicarboxiaminofenil)porfirinas e de uma N-(3,5-dicarboxifenil)quinolino[2,3,4-at]porfirina. As estruturas de todos os novos derivados porfirínicos foram confirmadas recorrendo às técnicas de ressonância magnética nuclear, espetrometria de massa e espetrofotometria de UV-vis. Em alguns casos algumas técnicas de RMN 2D, nomeadamente COSY, NOESY, HSQC e HMBC, foram também usadas. Na terceira parte, descrevem-se os resultados já obtidos na aplicação de 2-(4-carboxiaminofenil)porfirinas como corantes em dispositivos DSSC. Estes resultados foram sempre comparados com os de uma célula contendo o corante N719, tendo-se verificado uma eficiência de cerca de 30% do valor obtido com o uso do corante de referência.
The principal aim of this dissertation is related with the preparation of new porphyrinic derivatives with potential application as dyes in DSSCs through palladium-catalyzed coupling reactions and by oxidative cyclizations. This document is divided into three main parts. In the first part, are described the general characteristics of porphyrins, their spectroscopic properties, some synthetic methodologies to prepare meso-tetraarylporphyrins and functionalization of their β-pyrrolic positions, namely using palladium-catalyzed coupling reactions. In this chapter a special emphasis will be also given to the potentiality of porphyrins as dyes in DSSCs. In the second part is described the preparation of 2-(4-carboxyaminophenyl)porphyrins, obtained by the reaction of (2-amino-5,10,15,20-tetraphenylporphyrinato)nickel(II) with methyl 4-iodobenzoate in presence of palladium using Buchwald conditions, followed by ester function hydrolysis in basic medium. The oxidative cyclization of this class of compounds allowed the formation of N-(4-carboxyphenyl)quinolino[2,3,4-at]porphyrins, molecules bearing fused rings. The extension of these methodologies to dimethyl 5-bromoisophthalate gave rise to 2-(3,5-dicarboxyaminophenyl)porphyrins and one N-(3,5-dicarboxyphenyl)quinolino[2,3,4-at]porphyrin. All the new synthesized porphyrins were characterized by nuclear magnetic resonance, mass spectrometry and UV-vis spectrophotometry. In some cases, several 2D-NMR techniques were used, namely COSY, NOESY, HSQC and HMBC. In the third part, are described the results accomplished by 2-(4-carboxyaminophenyl)porphyrins as dyes in DSSC devices. The performance of these derivatives was always compared with a reference cell, containing N719 and values of power conversion efficiencies of about 30% of the more conventional Ru(II)-sensitizer N719 was achieved.
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Zhang, Lei. "Exploring Electron Transfer Dynamics of Novel Dye Sensitized Photocathodes : Towards Solar Cells and Solar Fuels." Doctoral thesis, Uppsala universitet, Fysikalisk kemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-302263.
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The design of dyes for NiO-based dye-sensitized solar cells (DSSCs) has drawn attention owing to their potential applications in photocatalysis and because they are indispensable for the development of tandem dye-sensitized solar cells. The understanding of the electron transfer mechanisms and dynamics is beneficial to guide further dye design and further improve the performance of photocathode in solar cells and solar fuel devices. Time-resolved spectroscopy techniques, especially femtosecond and nanosecond transient absorption spectroscopy, supply sufficient resolution to get insights into the charge transfer processes in p-type dye sensitized solar cell and solar fuel devices. In paper I-V, several kinds of novel organic “push-pull” and inorganic charge transfer dyes for sensitization of p-type NiO, were systematically investigated by time-resolved spectroscopy, and photo-induced charge transfer dynamics of the organic/inorganic dyes were summarized. The excited state and reduced state intermediates were investigated in solution phase as references to confirm the charge injection and recombination on the NiO surface. The charge recombination kinetics is remarkably heterogeneous in some cases occurring on time scales spanning at least six orders of magnitude even for the same dye. In this thesis, we also proposed a novel concept of solid state p-type dye sensitized solar cells (p-ssDSSCs) for the first time (paper VI), using an organic dye P1 as sensitizer on mesoporous NiO and phenyl-C61-butyric acid methyl ester (PCBM) as electron conductor. Femtosecond and nanosecond transient absorption spectroscopy gave evidence for sub-ps hole injection from excited P1 to NiO, followed by electron transfer from P1●- to PCBM. The p-ssDSSCs device showed an impressive 620 mV open circuit photovoltage. Chapter 6 (paper VII) covers the study of electron transfer mechanisms in a covalently linked dye-catalyst (PB-2) sensitized NiO photocathode, towards hydrogen producing solar fuel devices. Hole injection from excited dye (PB-2*) into NiO VB takes place on dual time scales, and the reduced PB-2 (PB-2●-) formed then donates an electron to the catalyst unit. The subsequent regeneration efficiency of PB-2 by the catalyst unit (the efficiency of catalyst reduction) is determined to ca. 70%.
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Cortez, Fernanda Cestaro Prado. "Consumo de álcool e outras drogas, sintomas depressivos, impulsividade e aspectos dimensionais de personalidade em homens biológicos profissionais do sexo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5142/tde-03012012-111632/.
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Introdução: Os homens biológicos profissionais do sexo (male sex workers MSW) constituem uma população heterogênea, de forma que uma classificação tipológica poderá promover o desenvolvimento de políticas públicas mais específicas. Embora existam diversas classificações para o homem que se prostitui nas ruas das cidades (street hustlers), há poucos estudos que avaliam aspectos psicopatológicos específicos desses indivíduos. Este estudo examina aspectos dimensionais da personalidade, impulsividade, uso de álcool e drogas e envolvimento com atividades criminais entre street hustlers da cidade de Santo André/SP. Método: Trata-se de um estudo seccional e retrospectivo, realizado pelo Ambulatório de Transtornos da Sexualidade da Faculdade de Medicina do ABC (ABSex), em associação com o Grupo Interdisciplinar de Estudos de Álcool e Drogas do Instituto de Psiquiatria da Faculdade de Medicina da Universidade de São Paulo (GREA Ipq FMUSP). Oitenta e seis sujeitos foram avaliados por meio de questionários autoresponsivos, sendo as entrevistas realizadas nas ruas de Santo André/SP, no próprio local de trabalho dos entrevistados, entre 2008 e 2010. Resultados: MSW portadores de transtornos de identidade de gênero (TIG) apresentaram maiores níveis de Esquiva ao Dano, mais frequente história de agressão física por parte dos clientes e menor oportunidade de outros empregos quando comparados com MSW sem TIG. MSW com uso inconsistente de preservativos apresentaram mais problemas com uso de álcool e drogas, maiores níveis de Dependência de Gratificação, mais frequente história de tentativas prévias de suicídio e antecedente criminal quando comparados a MSW com uso consistente de preservativos. Conclusões: A prostituição masculina é um fenômeno composto de múltiplos aspectos. Há múltiplas variações em termos de motivações e padrões de vida entre os MSW, de forma ser necessário dividi-los em categorias. A identidade e papel de gênero, uso de substâncias psicoativas e aspectos de personalidade são variáveis importantes a serem consideradas quando do desenvolvimento de políticas de saúde pública mais específicas. A habilidade em avaliar tais características pode ser ferramenta importante no desenvolvimento de propostas mais efetivas para o manejo dessa complexa populaçãoIntroduction: Male sex workers (MSW) are a heterogeneous population, and researchers aim to categorize them into typology groups to develop more specific public health policies. Although there are several classifications for MSW who work on streets (street hustlers), there are few studies that evaluate specific psychopathology aspects of these individuals. This study examines the dimensional aspects of personality, impulsiveness, alcohol and drug use, and criminal history among street hustlers in the city of Santo André/SP. Method: This is a cross-sectional and retrospective study, carried out by Ambulatory for the Treatment of Sexual Disorders of ABC Medical School (ABSex), in association with the Interdisciplinary Group of Studies on Alcohol and Drugs, Psychiatry Institute Faculty of Medicine - São Paulo University (GREA - IPQ - FMUSP). Eighty-six subjects were assessed through self-report questionnaires. The interviews were performed on the streets of Santo André/SP, in the workplace of the MSW, from 2008 to 2010. Results: MSW with gender identity disorder (GID) showed higher Harm Avoidance levels, more frequent history of physical aggression by clients and less opportunity of other jobs when compared with street MSW without GID. MSW with inconsistent condom use showed more alcohol and drug use problems, higher levels of Reward Dependence, higher frequency of personal history of suicide attempts and criminal history. Conclusions: Male prostitution is a phenomenon composed of multiple aspects. Variations of personal motivations and life patterns among MSW are huge. So it is necessary to divide them into clusters. Identity and gender roles, substance abuse, personality aspects, like Harm Avoidance and Reward Dependence, are important variables to be considered for the development of more specific public health policies. The ability to assess such characteristics may be an important tool in developing proposals for more effective management of this complex population
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El-Zohry, Ahmed M. "Exploring Organic Dyes for Grätzel Cells Using Time-Resolved Spectroscopy." Doctoral thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-263143.
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Grätzel cells or Dye-Sensitized Solar Cells (DSSCs) are considered one of the most promising methods to convert the sun's energy into electricity due to their low cost and simple technology of production. The Grätzel cell is based on a photosensitizer adsorbed on a low band gap semiconductor. The photosensitizer can be a metal complex or an organic dye. Organic dyes can be produced on a large scale resulting in cheaper dyes than complexes based on rare elements. However, the performance of Grätzel cells based on metal-free, organic dyes is not high enough yet. The dye's performance depends primarily on the electron dynamics. The electron dynamics in Grätzel cells includes electron injection, recombination, and regeneration. Different deactivation processes affect the electron dynamics and the cells’ performance. In this thesis, the electron dynamics was explored by various time-resolved spectroscopic techniques, namely time-correlated single photon counting, streak camera, and femtosecond transient absorption. Using these techniques, new deactivation processes for organic dyes used in DSSCs were uncovered. These processes include photoisomerization, and quenching through complexation with the electrolyte. These deactivation processes affect the performance of organic dyes in Grätzel cells, and should be avoided. For instance, the photoisomerization can compete with the electron injection and produce isomers with unknown performance. Photoisomerization as a general phenomenon in DSSC dyes has not been shown before, but is shown to occur in several organic dyes, among them D149, D102, L0 and L0Br. In addition, D149 forms ground state complexes with the standard iodide/triiodide electrolyte, which directly affect the electron dynamics on TiO2. Also, new dyes were designed with the aim of using ferrocene(s) as intramolecular regenerators, and their dynamics was studied by transient absorption. This thesis provides deeper insights into some deactivation processes of organic dyes used in DSSCs. New rules for the design of organic dyes, based on these insights, can further improve the efficiency of DSSCs.
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Elbatal, Hany. "Terpyridine-Based Metallo-Supramolecular Architectures: From Structure to Function." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1384367887.
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Arias, Olivares David. "Relation Among Localization, Delocalization and Physicochemical Properties. From Electron Density Databases to Magnetic Properties Effects of the acceptor unit in dyes with acceptor–bridge–donor architecture on the electron photo-injection mechanism and aggregation in DSSCs The role of Cr, Mo and W in the electronic delocalization and the metal–ring interaction in metallocene complexes." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS015.
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Tout d'abord, nous évoquerons un aperçu général de l'analyse topologique basée sur la densité d'électronique, le trou d'échange-corrélation et la densité de paires. Une fois la densité électronique rappelée, l'analyse topologique de la densité électronique est expliquée, ainsi que la procédure de calcul des points critiques de la densité électronique, le calcul de la matrice hessienne de la densité électronique et la définition des points critiques à la surface. Tous ces outils topologiques permettent de caractériser la nature des liaisons chimiques parallèlement à l'indice basé sur la délocalisation. Afin de comprendre la nature des énergies et des interactions dans les systèmes, l'analyse d'interaction non covalente est expliquée et combinée à l'analyse de décomposition d?énergie. De plus, les états de transition seront étudiés en appliquant les orbitales naturelles pour la valence chimique (ETS-NOCV). Les concepts clés du magnétisme moléculaire sont abordés. Nous nous concentrons sur l'aimantation et la susceptibilité magnétique, les composants diamagnétiques et paramagnétiques provenant de toute réponse magnétique dans les systèmes. Les propriétés de champs magnétiques induits sont étudiés dans le but de comprendre l'aromaticité à travers de deux descripteurs, les déplacements chimiques indépendants du noyau et les densités de courant induit. En annexe à la théorie, l'interaction isotrope dans les composés dinucléaires est introduite pour expliquer et mesurer certaines erreurs trouvées dans la théorie de la fonctionnelle de densité (TFD). [...]The first property here analysed and related with electronic localization/delocalization is the aromaticity. Aromaticity is an important concept introduced by Kekulé; since then, theoreticians and experimentalist have tried to understand it in different groups of molecules analogues to benzene. The importance of this concept and how the aromaticity is affected by the chemical environment is important to understand and link some physicochemical properties. i.e., reactivity, stability, magnetic response. The physicochemical properties of interest are the electronic structure, the nature of bonds and organometallic interactions(differentiation between metallocenes and metallabencenes). Furthermore, the magnetic response and the study of building blocks as possible candidates to make nano-wires or new low-dimension magnetic materials. Finally, we try to understand the interaction and the errors involved in some properties theoretically computed like, the isotropic coupling between metals through aromatic (or organic) units that have become important benchmark molecules to study magnetic properties in inorganic as well as metal-organic systems [...]
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Campos, Maria Angela Mirim da Rosa e. "Violência sexual como questão de saúde pública: atenção específica em serviços de saúde." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/6/6136/tde-05032007-143228/.
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A violência sexual caracteriza-se como complexo problema de saúde pública, que pode trazer conseqüências físicas e psicológicas para a saúde da pessoa exposta e vitimada. Em situações de risco, a contaminação pelas Doenças Sexualmente Transmissíveis e a gravidez indesejada podem ser prevenidas por meio da terapêutica quimioprofilática e transtornos emocionais podem ser amenizados mediante orientação psicológica precoce. O seguimento ambulatorial em especialidades, indicado pelo período de seis meses, possibilita verificar se houve eficácia na prevenção efetuada e orientar quanto à promoção à saúde. Com o intuito de conhecer algumas características das vítimas e de seus seguimentos ambulatoriais, avaliaram-se 305 prontuários de pessoas atendidas após violência sexual, em Centro de Referência, entre julho de 2003 a junho de 2004. Encontraram-se pessoas com idades até 77 anos e a mediana situou-se em 13 anos. Houve predomínio de vítimas do sexo feminino (89,2%), e as maiores freqüências foram observadas entre solteiras (49,8%), estudantes (47,2%) e com cor de pele branca (57%). Entre os agressores identificáveis, informados em 75,1% dos atendimentos, tiveram maior representatividade o padrasto (n=35) e o pai (n=31). Indicou-se profilaxia para gravidez em 23,9% dos atendimentos, para Doenças Sexualmente Transmissíveis em 29,5% e, para prevenção do vírus HIV, em 27,9%. Entre os seguimentos ambulatoriais, indicados nas especialidades de infectologia (70,8%) e ginecologia (58,8%), verificaram-se 60,4% de retorno em algum tipo de consulta em infectologia e 40,7%, em ginecologia. Seguimentos com psicólogo foram indicados para 98% das vítimas e destas, 23% passaram em algum tipo de retorno. Frente ao exposto, este estudo aponta para a necessidade de ações e políticas que possibilitem e favoreçam os seguimentos em consulta ambulatorial para vítimas de violência sexual, expostas ao risco de conseqüências à saúde física e psicológica.Sexual violence is considered to be a complex public health problem which can bring either physical or psychological consequences to the health of the exposed and victimized person. In risky situations, the contamination by Sexually Transmitted Diseases and the non desired pregnancy may be prevented through chemoprophylactic therapeutic and emotional disorders may be reduced with early psychological orientation. The outpatient follow up in specialty, indicated for a six month period, makes it possible to check if the prevention was really effective and to orient towards health promotion. Aiming to learn about the victim features and their outpatient follow up, 305 medical charts have been evaluated. All these people had been attended in Reference Center from July 2003 to June 2004, after suffering sexual violence. Peoples age went up to 77 years old and the median was 13 years old. Most victims were female (89,2%) and the highest frequency seemed to be among single (49,8%), students (47,2%) and Caucasian (57%). Among the identifiable aggressors, who had been informed in 75,1% of the cases, the stepfather (n=35) and the father (n=31) were the most representative. Prophylaxis for pregnancy (23,9%), for Sexually Transmitted Diseases (29,5%) and for preventing HIV virus (27,9%) were indicated. Among the outpatient follow up, which had been indicated in infectology (70,8%) and gynecology (58,8%), it has been observed that the outpatients who returned for at least some of the medical appointment were 60,4% in infectology and 40,7% in gynecology. Follow up with psychologists was indicated for 98% of the victims and among these, 23% have returned. Therefore , after all these data, this study aims to show the need of actions and policies which may enable and favor outpatient follow up for sexual violence victims who are exposed to risks, both for their physical and psychological health.
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Louk, Fanggi Butje Alfonsius. "Axial compressive behavior of FRP-concrete-steel double-skin tubular columns." Thesis, 2015. http://hdl.handle.net/2440/103454.
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A new type of composite structural system has been proposed in terms of FRP-concrete-steel double-skin tubular columns (DSTCs). This composite system consists of a steel tube inside, an FRP tube outside with concrete in between, and it combines the advantages of all three materials to achieve a high-performance structural member. This thesis is aimed at developing an improved understanding of the axial compressive behavior of DSTCs. To this end, six experimental studies were undertaken at the University of Adelaide. In each of these studies, the key parameters that influence the axial compressive behavior of DSTCs were identified and investigated. The results of these experimental studies indicate that concrete in a DSTC system is confined effectively by FRP and steel tubes. Both the normal-and high-strength concrete DSTCs exhibited a highly ductile compressive behavior under monotonic and cyclic axial compression. However, it is found that, for a given nominal confinement ratio, an increase in the concrete strength results in a decrease in the ultimate axial strain of DSTCs. The results also indicate that increasing the inner steel tube diameter leads to an increase in the ultimate axial stress and strain of concrete in DSTCs. It is observed that the concrete-filling of the inner steel tubes of DSTCs results in an increase in the compressive strength and a slight decrease in the ultimate axial strain of concrete in DSTCs, compared to the values observed in companion specimens with hollow inner steel tubes. It is also observed that cyclically loaded normal-strength concrete (NSC) DSTCs developed similar strength and strain enhancement ratios to those of monotonically loaded NSC DSTCs. The results also show that concrete in hollow DSTCs manufactured with square inner steel tubes develops significantly lower ultimate axial stresses and strains than those of concrete in companion hollow DSTCs with circular inner steel tubes. It is found, however, that the performance of these specimens improves dramatically when the square inner steel tube is filled with concrete. Apart from these experimental studies, this thesis also presents analytical models that were developed to predict the compressive strength and ultimate axial strain of concrete in DSTCs. The first of these models was developed to predict the compressive strength and ultimate axial strain of concrete in hollow circular DSTCs. After undertaking additional studies to expand the test database of square and concrete-filled DSTCs a second model that is applicale both circular and square and hollow and concrete-filled DSTCs was proposed. Comparison with experimental test results show that of the proposed models are in close agreement with the test results, and the models provide improved accuracy compared to the existing models.Thesis (Ph.D.) (Research by Publication) -- University of Adelaide, School of Civil, Environmental and Mining Engineering, 2015.
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Lee, Yi-ting, and 李怡葶. "Spirofluorenebithiophene containing organic dyes for DSSCs." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/61778773044227819356.
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碩士國立中央大學
化學研究所
97
New organic dyes that contain spiro [cyclopenta[2,1-b:3,4-b''] dithiophene-4,9''-fluorene] conjugate spacer between arylamine donor (diphenylamine, bis(4-methoxyphenyl) amine and carbazol) and the cyanoacrylic acid acceptor have been synthesized. These compounds are characterized by 1H NMR, 13C NMR, mass spectrometry, UV / visible spectrometer, fluorescent spectrometer and cyclic voltametry in the estimation of HOMO and LUMO energy levels. These dyes were developed as the sensitizers for the application in dye-sensitized TiO2 nanocrystalline solar sells (DSSCs). A power conversion efficiency (ηPCE) of 3.4 % was determined with the DSSC based on 6-(5-(4-(9H-carbazol-9-yl)phenyl)thiophen-6-yl)spiro[cyclopenta[2,1-b:3,4-b’]dithiophene-4,9’-fluorene]-2-cyanoacrylic acid (SCZ) under simulated AM 1.5 G irradiation (100 mW / cm2): short-circuit current density (Jsc) of 8.65 mA cm-2; open-circuit voltage (Voc) of 0.57 V; fill factor (FF) of 0.70. The experimental results show that the DSSC dyes possess spirofluorenyl group enhance the photo-stability, molar extinction coefficient, and the red-shifting of UV-visible absorption wavelength. Nevertheless, compared with the bithiophene centered DSSC dyes, the steric hindrance of the spirofluorenyl group impedes the dye adsorption on TiO2 and hence decrease the power conversion efficiency of DSSCs.
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Chiang, Wei-Hsiang, and 江維翔. "Properties of DSSCs at Very Low Intensity Condition." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/cvpcq3.
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碩士國立東華大學
光電工程學系
105
The purpose of this study is to investigate the optical and electrical properties of dye sensitized solar cell (DSSC) at very low intensity condition (VLIC). In order to test the effect of the DSSC after temperature and humidity test, some different dyes N719 and Z907 were selected for mixing TiO2 to make DSSC samples. In our experiment, the temperature and humidity test of sample was tested by using Weiss SB22/160. The testing conditions of temperature and humidity were set 50℃/75%RH, 65℃/85%RH, 70℃/75%RH and 85℃/85%RH.The electrical properties of DSSC samples were measured by using an I-V curve meter. The light radiation condition was set at the very low intensity condition (VLIC: 60 W/m2), which is defined for applications in low light intensity radiation. From our testing J-V curves of DSSC (N719 dye) with and without temperature and humidity test, the Voc, Jsc, FF and efficiency of DSSC sample before temperature and humidity test are 0.779V, 15(mA/cm2), 64% and 6.4% respectively, and the Voc, Jsc, FF and efficiency of DSSC sample are degraded to 0.779V, 9.56(mA/cm2), 70% and 4.58% respectively after 20 hour temperature and humidity test. Also from the J-V curves of DSSC (Z907 dye) with and without temperature and humidity test, the Voc, Jsc, FF and efficiency of DSSC sample before temperature and humidity test are 0.628V, 12.15(mA/cm2), 67% and 5.14% respectively, and the Voc, Jsc, FF and efficiency of DSSC sample are degraded to 0.655V, 6.06(mA/cm2), 67% and 2.67% respectively after 15 hours temperature and humidity test. In general, the optical and electrical properties of DSSC dye samples are degraded obviously after temperature and humidity test for 100 hours.
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Lee, Ting-Hui, and 李庭輝. "Dithiafulvalene-based dimer-type sensitizers for DSSCs application." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/17544623095738881108.
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碩士國立臺灣師範大學
化學系
101
A series of metal-free sensitizers consist of dithafulvalene (DTF) unit as the electron donor, benzene, thiophene or fluorine moiety as the conjugated segments and 2-cyanoacrylic acid as the electron acceptor have been synthesized via Suzuki coupling, Stille coupling, Horner-Wittig condensation, Vilsmeier-Haackformylation and Knoevenagel condensation reactions. The sensitizers can be of monomer-type (M1、M2、M4) or dimer-type (D2–D5). Cyclic voltammograms, differential pulse voltammograms and UV-Vis absorption spectra were used to estimate the HOMO and LUMO energy levels and its light harvest ability of the sensitizers in solution. Theoretical computations were also carried out on these dye molecules. The dyes were used as the sensitizers of dye-sensitized solar cells (DSSCs). The conversion efficiencies of the DSSCs fabricated range from 2.11 to 5.24％. The dimer-type dyes can more effectively suppress the π-π stacking of the molecules and the dark current. Electrochemical impedance spectroscopy (EIS) was also used to study the electron injection and recombination behaviors.
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Lin, Yung-Chun, and 林永峻. "Structures and properties of carbon nanotubes-assisted DSSCs electrodes." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/40062806952831626111.
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碩士明道大學
材料科學與工程學系碩士班
99
This work was to examine effects of MWNTs content and type of TiO2 in catalytic layer, layer sintering temperature, thickness and layer engineering on performance of the MWNTs-assisted dye-sensitized solar cells（DSSCs）. The cells were fabricated by the following steps：First, prepare aqua solutions of mixing TiO2 photocatalyst powders（from two different producers, UR P25 or Degussa P25）with acetylacetone dispersant, Triton X-100 surfactant, and MWNTs. The aqua solutions were then spin-coated several times on ITO glasses to vary the thickness of the catalytic layer. The coated layers were followed by sintering in an air furnace and then sorking in N3 dye solution. The LiI electrolyte was then filled into space between catalytic layer and Pt-coated counter electrode to form DSSCs. The cell performance was measured by using a solar simulator, the transmission and structures of catalytic layer were characterized by SEM, EDS, OM, XRD, and UV-Vis, respectively. From the experimental results, the following conclutions can be drawn. About effect of TiO2 type, the results show that a lower percentage of anatase phase in TiO2 powders（Degussa P25）may be the reason of producing cell with a greater short-circuit current (Jsc) and the cell efficiency. The results also indicate that MWNTs content, thickness and layer engineering of the catalytic layer play important roles on cell efficiency. The best cell efficiency is essentially a compromise between probabilities of optoelectronic reactions and transferring the generated electrons. The function of MWNTs is basically to enhance the transferring efficiency of electrons after optoelectronic reactions. Under the prescent conditions, the best cell performance（1.86％）is under the following conditions: 0.1wt％ MWNTs content, 3 times of spin-coating （or 4.9 μm in catalytic layer thickness）, catalytic layer engineering by spin-coating the catalytic layer without MWNTs as the blocking layer between electrolyte and catalytic layer. Regarding effect of sintering tempersture of the catalytic layer, it appeals that a higher sintering temperature results in a less porocity, so less dye adhesion and less contact opportunity of electrolye with ITO glass. The results indicate the highest tolerance sintering temperature（450℃）for ITO glass with catalytic layer could give a higher cell efficiency.
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Yen, Yin-Cheng, and 顏吟赬. "Synthesis of TiO2 nanomaterials and it̕s application on DSSCs." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/20956413983470582593.
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碩士國立中興大學
化學系所
98
TiO2-based FTO electrodes involving nanoparticles, nanotubes and whisker-like network have been prepared. The morphology was examined by high resolution transmission electron microscope (HR-TEM) and Field Emission Scanning Electron Microscope (FE-SEM). Their crystalline structure was evaluated by X-Ray diffraction and Raman spectroscopy. These TiO2-based FTO electrodes were then assembled with non-volatilize electrolyte for DSSCs ( dye sensitized solar cells ) . The effects of electrodes and the long time stability for DSSCs were studied. A mixture ratio of 1/0.1 (in v/v) of TiO2 nanoparticles/nanotubes was the best composition for TiO2-based FTO electrodes, showing the increasing of efficiency by 17％ at compared to full TiO2 nanoparticles. Upon the large ratio of TiO2 nanotubes, the TiO2-based films which had leaded to decease the efficiency. After 60 days, the efficiency (η)、open-circuit voltages (Voc) and short-circuit densities (Jsc) was increased, indicating that DSSCs with the non-volatilize electrolyte had long time stability .
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Yu, Chih-Jung, and 余智融. "A Novel Photo-Thermoelectric Generator Integrating DSSCs with Thermoelectric Modules." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/kh262x.
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碩士國立臺北科技大學
機電整合研究所
98
This study self-develops a novel type of photoelectric conversion modules, adopting pre-prepared dye-sensitized solar cells (DSSCs) and combing with nano-Cu thermoelectric thin film to cover on the sides of the thermoelectric generator (TEG) to absorb outside light to generate electricity and use recycled waste heat to re-generate electricity. And then, the close-loop pulsating heat pipe of filling nano-CuO fluid is prepared on the cooling-side to increase cooling effects and enhance whole power generation efficiency. Thus, this study focuses on the application of elevating efficiency of the thermoelectric modules. For the preparation of the thermoelectric modules, commercial nano-Cu powder is firstly used and the doctor blade is adopted to fabricate nano-Cu heat-transfer film, serving as the media of thermal conductivity and coated on the TEG to promote the output of heat flux and energy. Secondly, submerged arc nanoparticle synthesis system (SNASS) is used to fabricate the nano-CuO fluid and the filling close-loop pulsating heat pipe is applied to the cold side to employ the variation of gas and liquid to increase cooling effects. For the fabrication of photoelectric conversion modules, this study adopts DSSCs with multi-layer TiO2 nano-film to combine with two systems to assemble the photo-thermoelectric modules. For the test of photo-thermoelectric modules, I-V measuring system and heating platform are used to deal with the output effects and electrical storage loop system and nickel-metal hydride batteries are used to test electrical storage time of photo-thermoelectric modules. Finally, the temperature measurement device is employed to analyze the performance output and conversion efficiency of photo-thermoelectric modules by simulated light and practical light. Results shows when the heat source of photo-thermoelectric modules attains 90 ℃, 85.7% power output can be elevated. The temperature difference of cold and hot sides of TEG can reach 7oC shone by simulated light of photo-thermoelectric modules and thermoelectric conversion efficiency can achieve 2.17% and produce 11.32mW/cm2 power output, enhancing 1.4% compared to singly adopting DSSCs.
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Chang, Yang-Kai, and 張揚凱. "Application of carbon nanotubes/TiO2 nanoparticles composite electrode for DSSCs." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/06972578565836137653.
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Chou, Jing-Han, and 周靖翰. "Research on flexible DSSCs with nano structures and solid electrolytes." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/93567787118298655436.
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碩士國立雲林科技大學
電子工程系
103
Dye-sensitized solar cells (DSSCs) have been paid much attention recently because of low cost, simple process as compared to silicon solar cells that are of high cost and complicated process. To improve the photovoltaic performance of flexible DSSCs, this work has investigated the film coating conditions, the structures of the working electrode, and the materials for the electrolytes. In this work, both flexible ITO/PEN and ITO/PET have been used as the substrates for the flexible DSSCs. The flexible substrates have been pre-treated with baking to improve their electrical properties and light transmittance. For the DSSCs with TiO2 nanotubes and different colloids of TiO2 nano-particles as the working electrode, and added with TiO2 blocking layer, the best photovoltaic performance is: VOC = 0.71V, JSC = 4.76 mA/cm2, FF = 65.79%, and efficiency = 2.24%. For the DSSCs added with PVDF-HFP into the electrolyte as the solid electrolyte and added with P25 TiO2 nano-particles, the best photovoltaic performance has been improved as follows: VOC = 0.73V, JSC = 5.68 mA/cm2, FF = 63.71%, and efficiency = 2.63%.
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Jung-CheTsai and 蔡榮哲. "Fabrication of cobalt sulfide nanomaterials for counter electrode in DSSCs." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/50574936146087292723.
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博士國立成功大學
材料科學及工程學系
103
Because of high price of Pt noble metal, it is necessary to investigate new materials to replace the Pt as counter electrodes (CE) of DSSCs for industrial production. In this study, the cobalt sulfide nanomaterials with nanoflake arrays, mesoporous thin films and mesoporous nanotube arrays, respectively, are successfully fabricated on FTO coated glass by difference synthesis technologies including hydrothermal synthesis of Co(OH)2, mesoporous Co3O4 formation from cobalt-chelated chitosan, selective etching of ZnO sacrificial templates and ion-exchange reaction (IER). The mesoporous Co3O4 structures composed of the Co3O4 nanoparticles possess the high surface area and take advantage for further removal of templates and ion-exchange reaction. The mesoporous CoS2 structures are prepared by substitution of S2- for O2- after the IER at 90 ℃ for 4 hours. Morphologies and crystal structures of the CoS2 structures were characterized by SEM, TEM and XRD analyses. Their electrocatalytic properties were determined by electrochemical analyses including cyclic voltammetry (CV) measurement and Tafel polarization. Among all cobalt sulfides, the DSSC assembled with mesoporous CoS2 nanotube array CE achieved a highest power conversion efficiency of 6.13% under AM 1.5 condition, which was comparable to that of 6.04% for the DSSC with Pt CE. It indicates that the mesoporous CoS2 nanotube array can be a low-cost and efficient alternative for the reduction of electrolytes in DSSCs.
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Τζιογκίδου, Γεωργία. "Παρασκευή και μελέτη ευαισθητοποιημένων ηλιακών κυψελίδων (DSSCs) με μείγματα οργανικών χρωστικών." Thesis, 2013. http://hdl.handle.net/10889/7888.
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Αντικείμενο της διπλωματικής εργασίας είναι μελέτη της ευαισθητοποίησης από κοινού (co-sensitization) με την χρήση απλών οργανικών χρωστικών με παρόμοιο φάσμα απορρόφησης. Για το λόγο αυτό αναπτύχθηκαν μείγματα διαφόρων χρωστικών ουσιών τα οποία χρησιμοποιήθηκαν για την ευαισθητοποίηση ηλιακών κυψελίδων (DSSCs) με ημιαγωγό νανοδομημένου ZnO. Οι χρωστικές που χρησιμοποιήθηκαν για την ευαισθητοποίηση ήταν απλές οργανικές, όπως η Rose-Bengal, η Rhodamine-B, η Eosin-B, η Coumarin 343 και η Malachite Green. Παρασκευάστηκαν μείγματα δυο και τριών χρωστικών ουσιών με σκοπό την επίτευξη υψηλότερης απόδοσης της ευαισθητοποιημένης ηλιακής κυψελίδας.In this work we investigate co-sensitization effects by using simple organic dyes with complimentary absorption spectra. A combination of different organic dyes was used in this work to sensitize nanostructured ZnO films for Dye Sensitized Solar Cell (DSSC) devices. The dyes used to sensitize the films were the simple organic molecules Bengal Rose, Rhodamine B, Eosin B, Coumarin 343 and Malachite Green. Binary and ternary blends of these dyes were used in order to enhance the performance of ZnO DSSCs.
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Malta, Gabriela Rodrigues. "Sais de azólio – Síntese, reatividade e aplicabilidade como eletrólitos em DSSCs." Master's thesis, 2018. http://hdl.handle.net/10362/56360.
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As antraquinonas e os seus derivados são conhecidos pelas suas propriedades anticancerígenas. De modo a aumentar o seu potencial nesta área têm sido desenvolvidos novos compostos desta família. A síntese destes novos compostos é feita através da ligação de farmacóforos importantes ou conjugados (como os heterociclos de azoto) a análogos ativos desta família.
Recentemente verificou-se que ao fazer reagir sais de 1,2-dimetil-3-etil-imidazólio, com derivados de 9-antracenocarboxaldeídos na presença de base formava-se uma hetero-arilideno-9(10H)-antrona. Através de estudos biológicos concluiu-se que este composto apresentava atividade biológica de interesse, tendo-se considerado por isso que seria importante o desenvolvimento de análogos desta espécie.
Os sais de azólio, nomeadamente os de imidazólio e seus derivados, além de terem aplicações terapêuticas diversas são precursores de carbenos-N-heterociclos (NHCs) os quais para além de serem importantes catalisadores em síntese orgânica formam uma classe muito importante de líquidos iónicos que podem ser utilizados como eletrólitos ou solventes.
Inicialmente sintetizaram-se sais de 2-metil-imidazólio com diferentes substituintes na posição 3 e posteriormente fizeram-se reagir estes com derivados de 9-antraceno-carboxaldeídos na presença de base obtendo-se assim diferentes sais de hetero-arilideno-9(10H)-antronas. Também se realizaram trocas de contra-ião dos sais preparados pelos aniões NTf2- e docusato (AOT), o que permitiu obter espécies com propriedades diferentes. Com o intuito de avaliar a aplicabilidade dos compostos preparados noutras áreas fizeram-se estudos de voltametria cíclica e alguns dos sais de imidazólio preparados foram aplicados como eletrólitos em células solares sensibilizadas por corantes (DSSCs). Verificou-se que a sua utilização nestes dispositivos representa uma mais-valia uma vez que a sua aplicação se traduziu num aumento de eficiência das DSSCs.
Foi ainda estudada uma via sintética alternativa para a obtenção dos sais de hetero-arilideno-9(10H)-antronas através da reação da antrona com aldeídos por diferentes métodos, no entanto estas reações foram infrutíferas uma vez que a antrona é facilmente oxidada à antraquinona.
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Lu, Wen-jie, and 呂文傑. "Investigation of the scattering layer of DSSCs with different cover glasses." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/47685854348648462112.
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碩士國立雲林科技大學
電子與光電工程研究所碩士班
100
In this study, we investigated the scattering of different layer of titanium dioxide (TiO2) films and different texture of cover glasses for dye-sensitized solar cells (DSSCs). First, the TiO2 films were deposited on glass by the spraying with different layers. The thickness of TiO2 films would increase the photo-anode in order to enhance both dye adsorption and JSC. Secondly, the bidirectional scattering distribution function (BSDF) could descript the scattering status for these TiO2 layers. The value of BSDF always is occurred depending on the size of the particle of TiO2. Hence, the accuracy of the scattering would be examined again by the optical simulation of these layers. The last, the Trace-Pro software was used again to simulate the light-trap efficiency in the DSSCs with different cover glass. The results of optical simulation and measurement showed that the texture of Pattern 3 has the better trapping of light than other patterns for the cover glass.
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Wang, Wei-Yan, and 王偉彥. "A STUDY OF DSSCS BASED ON TCO-PT-FREE FLEXIBLE COUNTER ELECTRODES." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/c62e4f.
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碩士大同大學
化學工程學系(所)
102
In this study, we first utilize the high temperature reflux mode to well mix the CNT and PP and followed by thermal compression to prepare the CNT/PP thin plates as a Pt-free and TCO-free CE for DSSCs. After that, to further carry out the test of materials characterizations and electrochemical activity. Although the cell efficiency of DSSCs using CNT/PP based CEs was still much lower than that of DSSC with Pt/FTO CE, it is showed the excellent sheet resistance and flexibleness. Therefore, we used the CNT/PP to replace the FTO glass as a substrate. In order to enhance the photovoltaic performance, we further deposited PEDOT thin film on flexible CNT/PP plates via electropolymerization method as a PEDOT-CNT/PP CE. From a series of results and discussion, the composites of PEDOT-CNT/PP exhibited excellent electrocatalytic activity and low charge transfer resistance. On the other hand, after the optimization of flexible test, the CNT/PP plate prepared in the ratio of CNT/PP with 43% possessed the highest bending ability. However, the power conversion efficiency of the PEDOT coated on CNT/PP with 43% is 6.09%, which is lower than Pt/FTO CE (6.69%). In the bending characteristics, the composites of PEDOT-CNT/PP showed the excellent potential as a low-cost and flexible composites CE in DSSCs.
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謝佩珊. "The studies of oligoene dyes with different functional groups for DSSCs applications." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/75384972854657210735.
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碩士國立臺灣師範大學
化學系
98
In this study, ten new donor π-conjugated acceptor (D--A) organic dyes have been engineered and synthesized as sensitizers for the application in dye-sensitized solar cells (DSSCs). The structures of organic dipolar dyes compose of an electron donor (carbazole, dimethylamine, or diphenylamine), a -conjugated framework, and an electron acceptor (carboxylic acid or cyanoacrylic acid). The photophysical and electrochemical properties of these dyes were studied in details.The assembled DSSCs base on these dyes were measured to evaluate the performance. The amount of dye adsorption on TiO2 and the oxidation potential are dependent on the dye structure. The higher performances were obtained by DSSCs based on dye 19. The solar-to-electrical energy conversion efficiency () of 3.03% is achieved under simulated AM 1.5 irradiation (100 mW/cm2) with a DSSC based on dye 19 (Voc = 648 mV, Jsc = 6.68 mA/cm2, ff = 0.70). Density functional theory (DFT) calculations have been performed on the dyes, and the results show that effective charge separation exist in the charge transfer states.
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Wang, Peng Siang, and 王鵬翔. "The high temperature Debye behavior of DSSCs with indium-doped ZnO nanostructures." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/zs25fe.
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碩士長庚大學
光電工程研究所
104
Zinc oxide (ZnO) has the unique nature and various application. ZnO is a distinct kind of metal oxide semiconductor with a wide direct-band gap of 3.37 eV and large exciton binding energy (60 meV). Therefore it is appropriate to produce the opto-electronic applications, such as solid state lighting and solar cells. ZnO is the n-type intrinsic semiconductor, so we used the other way to change ZnO optical character by doping. In this experiment, we used the simple hydrothermal method to grow indium-doped ZnO nanostructure on indium tin oxide glass(ITO). Then the sample were respective by immersing in N-719 dye solution and further make the dye-sensitized solar cell application. We analyzed structure, optical characteristics of the ZnO nanomaterials, and its ability to convert solar energy to electrical energy in the DSSC by using the X-ray diffraction (XRD), scanning electron microscope (SEM) and the solar simulator. In addition, we also studied the photovoltaic performances of ZnO nanostructured films in different temperature by using photoluminescence (PL) spectra. We use these measuring instruments to know that the different nano structures will effect different device characteristic, and we analysis Debye temperature to find out how different nsno structure effect different device characteristic.
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Lin, Chien-Ting, and 林建廷. "Synthesis and Research of Novel Ruthenium Complexes Containing Fluorous Bipyridine for DSSCs." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/8hwv9e.
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碩士國立臺北科技大學
有機高分子研究所
97
A new type of Ru-based solar cell dye complexes has been synthesized successfully and applied to dye-sensitized solar cells. With our particular by designed novel fluorous bipyridine ligand [4,4’-bis(RfCH2OCH2)-2,2’-bipyridine] together with [4,4’-dicarboxy-2,2’-bipyridine], we have achieved the dye complexes [Ru(dcbpy)(4,4’-bis-(RfCH2OCH2)-2,2’-bpy)(NCS)2] (1a-c) where Rf=n-HC2F4(1a), n-C3F7(1b), n-HC4F8(1c), respectively. After purification by column chromatography, the products were analyzed and spectroscopically characterized by multi-nuclei NMR (1H,19F and 13C), FTIR, GC-MS and FAB. Taking advantage of the fluorous bipyridine ligands; which are hydrophobic and water repellent, we can use the fluorous bipyridine to improve the function of traditional DSSC, with stability and the efficiency. According to early papers, we know the different carbon length of fluorous arms on bpy ligands will lead to diverse effects. In my thesis, I have compared the difference among our own dyes, N3, Z907 and N719, with instrumental analysis such as CV, UV to see to what extent the improvents were made.
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Li, Wan-Qian, and 李宛蒨. "Enhanced Performance of DSSCs with Organic Sensitizers Containing Multiple D-π-A Branches." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/vwr4j9.
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碩士國立中央大學
化學學系
103
Dye-sensitized Solar Cells (DSSCs) have attracted intense interest due to their environmental friendly nature, low cost of production, and easy fabrication. The sensitizer is a key component of DSSC and have been studied widely due to its important effects in light harvesting, charge separation, and power conversion efficiency. In addition to Ru-based dyes, metal-free organic dyes have also received great attention for their unique advantages such as higher molar extinction coefficients, low cost of materials, facile molecular designs, and easy syntheses process. In my research, a series of tertiary amine dyes (TD01, TD02, and TD03) consisting of different number (one, two, and three, respectively) of D-π-A units which are connected through oxygen of donor group to alkyl moiety of tertiary amine have been synthesized. Presumably, the increased D-π-A fragment of each dye could enhance the absorption intensity in UV-visible spectrum of the respected dye, having a chance to transform more absorbed photons into electrons, and thus improve Jsc. The dye TD03 with its three D-π-A units in three directions from central amine core, is expected to spread over effectively and bind to TiO2 surface and minimize the dye aggregation if any. Further, the bridging ethyl groups between D-π-A division and central nitrogen can be served as a barrier at TiO2-electrolyte interface, thereby retarding electron recombination and enhancing Voc.
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Yen, Chuan-Yu, and 顏銓佑. "Preparation and Properties of Carbon Nanotubes/Nanocomposite for Dye-Sensitized Solar Cells (DSSCs)." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/99813742366152805097.
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