Dissertations / Theses on the topic 'Sb₂Se₃'
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Wang, Wei [Verfasser]. "Sb2S3/Sb2Se3 Nanostructures and Applications / Wei Wang." Konstanz : KOPS Universität Konstanz, 2019. http://d-nb.info/1201276012/34.
Full textParnell, Harriet. "Towards a Ge-Sb-Se/S hyperspectral imaging probe for early cancer diagnosis." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/53605/.
Full textTunc, Fidel. "Fastställande av SB/AD-status för SE-KOL och överföring till ett bättre uppföljningssystem." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-18991.
Full textARELLANO, MERYELEM TANIA CHURAMPI. "REMOVAL OF AS, SE, SB AND BI FROM WATERS AND INDUSTRIAL EFFLUENTS BY CHEMICAL PRECIPITATION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30305@1.
Full textCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Os efluentes industriais dos processos de mineração e metalurgia extrativa, podem conter variáveis teores de As, Se, Sb e Bi tornando-se uma fonte potencial de poluição. O presente trabalho teve como objetivo estudar a remoção de As, Se, Sb e Bi presentes na mesma solução aquosa, por precipitação química empregando íons de agentes precipitantes, em condições oxidantes e reduzidas. Para isso, foram empregadas soluções sintéticas mistas dos analitos. As variáveis avaliadas foram: tipo de agente precipitante (Fe(III), Fe(II), Al(III) e Ca(II)), pH, relação molar agente precipitante/analito, concentração inicial de As, Se, Sb e Bi e a pré-oxidação destes elementos com H2O2. Para soluções contendo concentração inicial de 200 mg/L dos analitos sem pré-oxidação, foi possível atingir 99,95 por cento de eficiência de remoção e concentrações residuais de 0,11 mg/L, 0,10 mg/L, 0,08 mg/L, 0,01 mg/L para As, Se, Sb e Bi, respectivamente, por precipitação com Fe(III), a pH 5 em 30 minutos de reação e relação molar Fe(III)/As, Se, Sb e Bi = 7. Esses valores obtidos enquadram-se dentro do permitido pela resolução CONAMA 430/2011 para descarte de efluentes de As e Se. Sendo que o pH ótimo para precipitar As, Se, Sb e Bi depende do estado de oxidação de seus oxiânions, enquanto o agente precipitante Fe(III) foi bem superior ao Fe(II), Al(III) e Ca(II) para remover As, Se, Sb e Bi sem ou com pré-oxidação. A pré-oxidação desses elementos com H2O2 influenciou na remoção de As e Se, uma vez que o As foi bem melhor removido com pré-oxidação e Se sem pré-oxidação. Já o Sb e Bi não foram influenciados pela pré-oxidação. A relação molar ótima de Fe(III)/As, Se, Sb e Bi foi de 5 e 7 Finalmente as micrografias obtidas por MEV mostram uma estrutura compacta aglomerada de tamanho irregular, variando de protuberância de várias dezenas de mícrons e, a análise semiquantitativa mostrou que estão constituídos principalmente pelos elementos As, Se, Sb, Bi, Fe, O, Cl e Na, estando Fe e O em maior quantidade.
The industrial effluents from mining and extractive metallurgy processes may contain varying amounts of As, Se, Sb and Bi becoming a potential source of pollution. The object of the present work was to investigate the removal of As, Se, Sb and Bi present in the same aqueous solution, by chemical precipitation using cations of precipitating agents, under oxidizing and reduced conditions. For this, mixed synthetic solutions. The variables evaluated were: precipitating agent type (Fe (III), Fe (II), Al (III) and Ca (II)), pH, precipitating /analytes molar ratio, initial concentration of As, Se, Sb and Bi And the preoxidation of these elements with H2O2. For solutions containing the initial concentration of 200 mg / L of the analytes without pre-oxidation, it was possible to achieve 99.95 percent removal efficiency and residual concentrations of 0.11 mg / L, 0.10 mg / L, 0.08 mg / L, 0.01 mg / L for As, Se, Sb and Bi, respectively, by Fe (III) precipitation, at pH 5 in 30 minutes of reaction and Fe (III) / As, Se, Sb and Bi = 7. These values are within the limits allowed by CONAMA Resolution 430/2011 for the disposal of As and Se effluents. The optimum pH to precipitate As, Se, Sb and Bi depends on the oxidation state of its oxyanions, while the Fe (III) precipitating agent was well above Fe (II), Al (III) and Ca (II) to remove As, Se, Sb and Bi. Pre-oxidation of these elements with H2O2 influenced the removal of As and Se, however Sb and Bi were not influenced by pre-oxidation. The optimal molar ratio of Fe (III) / As, Se, Sb and Bi was 5 and 7 to precipitate these elements. Finally, the micrographs obtained by MEV show a compact agglomerated structure, and the semiquantitative analysis showed that they are constituted mainly by elements As, Se, Sb, Bi, Fe, O, Cl and Na , With Fe and O being in greater quantity.
Butterworth, Jessica Helen. "Mid-infrared transmitting Ge-Sb-Se chalcogenide glass fibres : for potential use in medical diagnostics." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/43326/.
Full textRouxel, Olivier. "Géochimie isotopique des métaux (Fe, Cu, Sb) et des metalloides (S, Se) dans la croûte océanique." Vandoeuvre-les-Nancy, INPL, 2002. http://www.theses.fr/2002INPLA43N.
Full textLuo, Yandi. "Development of new buffer layers and rapid annealing process for efficient Sb₂Se₃ thin-film solar cells." Electronic Thesis or Diss., Université de Rennes (2023-....), 2024. http://www.theses.fr/2024URENS039.
Full textIn this thesis, heterojunction interface behavior, grain growth process and alternative buffer layer of Sb₂Se₃ based solar cells were investigated. The absorber quality and the band alignment are identified as key parameters for reducing defect density and for facilitating the separation and the transport of photogenerated charge carriers. A strategy of Al³⁺ doping into the CdS buffer layer was introduced in Sb₂Se₃ solar cells. The band alignment and the interface quality have been significantly improved. A “spike-like” structure was obtained for the best device with an efficiency of 8.41%. Secondly, a rapid thermal annealing process has also been developed and optimized in order to improve the quality of Sb₂Se₃ absorber film with reduced defect density. The efficiency of the Sb₂Se₃ solar cells is increased to 9.03%. In addition, we have tried to replace the toxic CdS buffer layer with an environmentally friendly ZnSnO film with moreover a wider band gap. An interesting power conversion efficiency of 3.44% was achieved for the Cd-free Sb₂Se₃ thin-film solar cells
Bonnisseau, Dominique. "Etude des structures magnétiques de composés de neptunium (Np As, Np Sb, Np Se et Np Ru Si)." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37603161k.
Full textLecomte, Alicia. "Modélisation des défauts et des propriétés de transport au sein de semi-conducteurs à base de Sb₂Se₃ pour le photovoltaïque." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S056.
Full textIn a context of global ecological concerns, renewable solar energies are an attractive and promising solution. Technologies to exploit this energy are in constant progress, particularly since two decades. However, there is still way to go for this clean energy to be competitive with fossils fuels. New absorbers are required, especially for developing flexibles thin-films solar cells. This thesis is dedicated to the study and rationalization of defects within the promising Sb₂Se₃-based materials for photovoltaic absorption. Theoretical study, via density functional theory, has been performed to improve the understanding of the material. Indeed, Sb₂Se₃ shows a low p-type conductivity and it can be doped to obtain a n-type semiconductor. The doping mechanism should be better understood for a better control. The Sb₂Se₃ intrinsic defects have been studied in detail. Experimentally measured conductivity arises from the addition of all defects. It has been demonstrated that selenium substituted by antimony will lead to an electron-donor material. The results indicate that the most favorable crystallographic site for creating defects is at the end of the (Se₄Seb₆)n ribbon, with the lowest coordination. On the other hand, extrinsic doping has also being considered for achieving electron donor or acceptor semiconductor, in order to have design a homo-junction. Simulation and experimental results show that Tin doping for p-type semiconductor, chloride or bromide doping e for n-type semiconductor, can increase greatly the charge carriers' mobility and concentration
Muñoz, Estrada Vianett Berenice. "Characterization of n-type Bi₂Te₂.₇Se₀.₃ and p-type Bi₀.₅Sb₁.₅Te₃ ternary like semiconductors fabricated by shock-waved (explosive) consolidation." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2007. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Full textGunasekera, Kapila J. "Intermediate Phase, Molecular Structure, Aging and Network Topology of Ternary GexSbxSe100-2x Glasses." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1277132558.
Full textUrbánková, Kristýna. "Multikomponentní extrakce a prekoncentrace mikrokoncentrací As, Sb, Se a Te na modifikovaný silikagel, stanovení na ICP-AES (ICP-MS) a aplikace na vzorky vod." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-233280.
Full textCrispino, Carla Cripa. "Determinação de As, Sb e Se em material agronômico por espectrometria de emissão óptica acoplada a plasma induzido com geração de hidretos (HG-ICP-OES)." Universidade Federal de São Carlos, 2005. https://repositorio.ufscar.br/handle/ufscar/6620.
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With the objective to attain maximum productivity with small costs, organic and inorganic chemical parameters are used to evaluate and monitoring crops and animals development. Inorganic amounts in agronomic samples have great importance in the production evaluation. Some of elements in those samples could be an indicative of quality, owing to their requirement (Se) or toxicity (As, Sb), even when they are present in µg kg-1 levels, needing a technique with high sensibility for quantification. The aim of this work was the development of a simple system of hydride generation by continuous flow combined with an inductively coupled plasma optical emission spectrometry for simultaneous determination of As, Sb and Se in agronomic samples. The work attained to a gas-liquid separator development, and an experimental planning to established the chemical and instrumental conditions of hydride generation. The HCl, NaBH4 and KI concentrations, such as the R.F. power, carrier gas flow and the viewing height, were evaluated besides the study of a more appropriate sample preparation. Limits of detection of the proposed system were 0.1 µg L-1 for As, Sb and Se and the limits of quantification were 0.3, 0.2 and 0.2 µg L-1 for As, Sb and Se respectively with RSD smaller than 10% and 30 samples per hour of reading speed. In view to observe the accuracy, four different kinds of samples forage and bovine-derived samples (blood, viscera and semen) were spiking with analytes concentration in the µg L-1 level. Recoveries around 77 to 112% were found. The results present the possibility to use the proposed system in agronomic projects developed with the objective to determine essential and toxic analytes in different kinds of feed and animal samples, contributing to evaluation of nutritional demands and the increase of efficiency in the bovine production systems.
Com o objetivo de atingir a maior produtividade com menores custos, parâmetros químicos, orgânicos e inorgânicos, são usados cada vez mais para avaliar e monitorar o desenvolvimento de uma cultura ou espécie. A determinação de constituintes inorgânicos em amostras agronômicas possui grande importância na avaliação da produção. Alguns elementos presentes nessas amostras são indicativos da qualidade devido à essencialidade (Se) ou toxicidade (As, Sb), porém estão presentes na ordem de µg kg-1, necessitando de uma técnica com alta sensibilidade para quantificação. O objetivo deste trabalho foi o desenvolvimento de um sistema simples de geração de hidretos por fluxo contínuo acoplado a um espectrômetro de emissão óptica com plasma induzido para a determinação simultânea de As, Sb e Se em amostras agronômicas. Esse trabalho envolveu o desenvolvimento de uma câmara de separação gás-líquido e um planejamento experimental para a definição das melhores condições químicas e instrumentais da geração de hidretos. Foram estudadas a concentração de HCl, NaBH4 e KI; a potência de radiofreqüência do plasma, o fluxo do gás carregador e a altura de observação do plasma, além do estudo do preparo de amostra mais adequado. Usando as condições otimizadas, foram obtidos limites de detecção de 0,1 µg L-1 para As, Sb e Se e limites de quantificação de 0,3; 0,2 e 0,2 µg L-1 respectivamente para As, Sb e Se com RSD menores que 10% e velocidade de leitura de 30 amostras por hora. Para observar a exatidão do procedimento proposto quatro amostras diferentes - forrageira e amostras bovinas (sangue, víscera e sêmen) - foram dopadas com os analitos na ordem de µg L-1. Recuperações entre 77 e 112% foram encontradas. Espera-se com essa proposta a complementação dos estudos que determinam analitos essenciais e tóxicos em amostras de tecido, fluídos e na alimentação bovina, contribuindo para a avaliação das exigências nutricionais e o aumento da eficiência dos sistemas de produção de bovinos.
Soares, Jocelene. "Determinação de As, Bi, Sb, Se, Sn e Te por injeção em fluxo com geração de hidretos acoplada a espectrometria de massa com plasma indutivamente acoplado." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/10480.
Full textIn this work it is proposed the development of flow injection systems for hydride generation coupled to inductively coupled plasma mass spectrometry (FI-HG-ICPMS) for determination of trace elements (As, Bi, Sb, Se, Sn and Te) in lead alloys employed in automotive battery. Due to the characteristics of the sample matrix, manly the presence of high concentrations of lead that can interfere in hydride generation technique, a detailed investigation of the influence of the physical and chemical parameters was made. The carrier solution concentration (HCl) reductant concentration (NaBH4 solution), reaction coil length and sample volume were evaluated. As the ICP-MS is a multielmentar technique, the parameters were optimized in order to determine simultaneously the highest number of elements. Three different configurations of FI systems were tested: a) a single channel system; b) a two channel system with one gas/liquid separator; and, c) a two channel system with two gas/liquid separators. According to the characteristics of the elements, two groups were separated: one group containing As, Bi, Se and Te were 6.0 mol l-1 HCl is necessary as sample carrier solution and another group containing Sb and Sn were 0.1 mol l-1 HCl is used as sample carrier. The compromise conditions of NaBH4 concentration, carrier gas (Ar) flow rate, sample volume and reactor coil length were 0.6% (m/v), 1.25 L min-1, 87 μL and 50 cm, respectively, for both groups of elements. Both systems with two reaction channels allow the simultaneous determination of the two groups of elements. Strong analyte signal suppression in presence of Pb, Ag, Bi and Cu was observed. However, the interference could be overcome by using the optimized conditions for hydride generation. By using the proposed FI-HG-ICP-MS systems it was possible to determine relatively low concentrations of Bi, Sb, Se, Sn and Te in lead alloys. The limits of detection were 0.34, 0.01, 0.01, 0.01, 0.01, 0.01 mg g-1 of As, Bi, Sb, Se, Sn and Te, respectively. The accuracy of the developed method was evaluated by using analyte recovery tests where the results were in range 94 to 103%.
Neste trabalho foram desenvolvidos sistemas de injeção em fluxo (FI) para a geração de hidretos (HG) acoplados a espectrometria de massa com plasma indutivamente acoplado (FI-HG-ICP-MS), para a determinação de elementos traço em liga de chumbo empregada em baterias automotivas. Devido às características da matriz da amostra, principalmente devido a presença de Pb, foi feita uma investigação detalhada dos parâmetros físicos e químicos da HG como, a concentração da solução carregadora (HCl), concentração do redutor, comprimento do reator e o volume de amostra injetado. Para a eficiente geração dos hidretos voláteis foi necessário estabelecer uma condição de compromisso. Desta forma, para As, Bi, Se e Te foi usada como solução carregadora da amostra HCl 6,0 mol L-1 e HCl 0,1 mol L-1 para Sb e Sn. A concentração de NaBH4, vazão do gás de arraste (Ar), volume de amostra injetado e o comprimento do reator foram 0,6% (m/v), 1,25 L min-1, 87 μL e 50 cm, respectivamente, para ambos os grupos de elementos. Após estabelecidas as condições reacionais para a geração de hidretos, foram desenvolvidos três sistemas FI. Um sistema FI com um canal de reação e dois sistemas com dois canais de reação, com um e dois separadores gás-líquido. Os sistemas com dois canais de reação permitem a determinação simultânea dos dois grupos de elementos. Forte supressão de sinal foi observada na presença de Pb, Ag, Bi e Cu porém, estas foram contornadas, particularmente, pelas condições reacionais da geração de hidretos e o reduzido volume de amostra injetado. Desta forma, utilizando os sistemas propostos foi possível a determinação de concentrações relativamente baixas para Bi, Sb, Se, Sn e Te em amostras de liga de chumbo. Os limites de detecção obtidos foram de 0,34, 0,01, 0,01, 0,01, 0,01, 0,01 mg g-1 para As, Bi, Sb, Se, Sn e Te, respectivamente. A exatidão do método proposto foi avaliada através de teste de recuperação dos analitos, sendo que os mesmos ficaram na faixa entre 94 e 103%.
Krausová, Veronika. "Evidence obyvatel podle zákona 133/2000 Sb. se zaměřením na místo trvalého pobytu a problematika „úředních adres“ při výkonu státní správy a občanskoprávních řízeních." Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-260021.
Full textCibulková, Pavlína. "Evidence obyvatel podle zákona 133/2000 Sb. se zaměřením na místo trvalého pobytu a problematika „úředních adres“ při výkonu státní správy a občanskoprávních řízeních." Master's thesis, Česká zemědělská univerzita v Praze, 2017. http://www.nusl.cz/ntk/nusl-262932.
Full textWANDEKOKEN, FLÁVIA GALVÃO. "DEVELOPMENT OF METHOD FOR DETERMINATION OF AS, SB AND SE IN BIODIESEL AND PETROLEUM BY INDUCTIVELY COUPLED PLASMA OPTICAL EMISSION SPECTROMETRY WITH SAMPLE INTRODUCTION BY HYDRIDE GENERATION (HG ICP." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18416@1.
Full textCom o aumento da população mundial e o consequente aumento das atividades industriais e consumo de combustíveis, a poluição química vem sendo um grande problema do século XXI. Alternativas que possam minimizar tal problemática são alvos de pesquisas, como o uso de biodiesel, um combustível renovável e menos poluente. Elementos normalmente encontrados em baixas concentrações, como As, Sb e Se, tornam-se tóxicos à saúde humana quando em concentrações acima de certos limites e, por isso, devem ser monitorados em diversas amostras, como combustíveis. Para o Sb, a dose diária aceitável (DDA) é de 6 ug dia(-1) para cada kg de peso corporal e para o Se, valores de concentração acima de 50(-200) ug por dia já são considerados tóxicos. O limite aceitável de As em água potável é de 0,01 mg L(-1) e valores acima de 7,5 x 10-3 ug m(-3) são associados a risco de câncer de pulmão. Esses elementos podem ser constituintes originais do petróleo e seus derivados ou ser adicionados como contaminantes em alguma etapa do refino. No caso do biodiesel, podem estar presentes, decorrente do uso de fertilizantes e pesticidas nas lavouras das plantas que deram origem ao óleo usado na produção desse combustível. Estes elementos podem, durante o processo de combustão dos combustíveis nos motores, ser liberados para a atmosfera. As baixas concentrações em que esses elementos se encontram, normalmente, estão abaixo do limite de detecção de algumas técnicas, como ICP OES com introdução de amostra por nebulização pneumática convencional. Nesse caso, uma alternativa viável é a introdução da amostra por geração de vapor, que proporciona uma melhora significativa na sensibilidade das técnicas analíticas. Este trabalho teve como objetivo determinar simultaneamente As, Sb e Se em amostras de óleo cru e biodiesel, utilizando HG-ICP OES. Para tanto, as amostras tiveram que ser submetidas à decomposição ácida em bloco digestor. Foram estudadas diferentes condições de pré-redução (HCl, tiouréia e ácido ascórbico com KI), avaliadas suas concentrações e tempo de aquecimento. As condições empregando HCl e tiouréia foram as que apresentaram melhores resultados e tiveram seus parâmetros otimizados multivariadamente, assim como os parâmetros da geração de vapor: vazão de amostra, vazão de NaBH4 borohidreto de sódio e vazão do gás de arraste. Estabelecidas as melhores condições para análise e respeitando-se as limitações da técnica, o método foi avaliado através da análise de material certificado de óleo combustível residual (NIST 1634c), biodiesel de óleo de soja (NIST 2772) e biodiesel de gordura animal (NIST 2773), empregando-se as duas condições de pré-redução citadas. Nesse caso, o uso de HCl como pré-redutor foi mais eficiente, com recuperações entre 90% e 99% para os 3 analitos. Já a pré-redução com tiouréia foi eficiente só para Sb, com recuperação em torno de 104%, enquanto as recuperações para As e Se foram entre 57% e 29%. Sendo assim, para o método proposto empregou-se HCl como pré-redutor. As condições otimizadas para a geração e empregadas para as análises das amostras foram: vazão da amostra, 3,0 mL min(-1); vazão do NaBH4 1,5 mL min(-1); vazão de gás de arraste 0,8 L min(-1) e concentração do HCl 8 mol L(-1). Um estudo para verificar uma possível interferência de Ni nas condições otimizadas para a geração de vapor revelou que este interferente não prejudica as determinações de As, Sb e Se quando se emprega HCl 8 mol L(-1). Sendo assim, analisaram-se as amostras de óleo cru e biodiesel nas condições previamente otimizadas. Foi detectada a presença de apenas As e Se nas amostras de óleo cru enquanto as amostras de biodiesel não apresentaram concentrações de As, Sb e Se acima dos LODs obtidos. Embora as recuperação para as adições de Sb nas amostras de biodiesel e óleo cru tenham ficado dentro de um intervalo relativamente grande, entre 72% e 111%, evidenci
With the increasing world population and the consequent increasing in industrial activities and fuel consumption, chemical pollution has been a major problem of the XXI century. Alternatives that can minimize such problems are targets of researches, such as the use of biodiesel, a renewable and less polluting fuel. Elements usually found in low concentrations, such as As, Sb and Se, become toxic to human health when in concentrations above certain limits and, therefore, should be monitored in several samples, such as fuels. For Sb the acceptable daily intake (ADI) is 6 mg day(-1) for each kg of body weight and, for Se, concentrations above 50-200 mg per day are considered toxic. The As acceptable limit in drinking water is 0.01 mg L(-1) and values above 7.5 x 10-3 g m(-3) are associated to risk of lung cancer. These elements may be original constituents of petroleum and its derivatives or be added as contaminants at some step of the refining process. In the case of biodiesel, these elements can be present due to the use of fertilizers and pesticides in the crops that produce the oil used in the biodiesel production. These elements can be released to the atmosphere during the fuel burning in the motor. The usually low concentrations of these elements can be below the detection limit of some techniques, such as ICP OES with sample introduction by standard pneumatic nebulization. In these case, the vapor generation is an interesting alternative for sample introduction, since it provides a significant improvement in the sensitivity of the analytical technique. This study aimed to simultaneously determine As, Sb and Se in crude oil and biodiesel samples, using HG-ICP OES. For that, samples had to be subjected to acid decomposition in a block digester, thus allowing calibration with inorganic standard solutions. Different pre-reduction conditions were studied (HCl, thiourea and ascorbic acid with KI), being evaluated the reagents concentrations and heating time. The conditions using HCl and thiourea showed the best results and had their parameters multivariate optimized, as well as the parameters of the vapor generation: sample, sodium borohydride and carrier gas flow rates. Established the best conditions for analysis and respecting the limitations of the technique, the method was validated by analysis of a residual fuel oil certified material (NIST 1634c), biodiesel from soybean oil (NIST 2772) and biodiesel from animal fat (NIST 2773), using the two cited pre-reduction conditions. In this case, the use of HCl as pre-reducer was more efficient, with recoveries between 90% and 99% for the three analytes. Pre-reduction with thiourea was effective only for Sb, with recovery around 104%, while the recoveries for As and Se were between 57% and 29%. Thus, HCl was employed as the pre-reducer in the proposed method. The optimized conditions for the generation and used for the analysis of the samples were: sample flow rate, 3.0 mL min(-1); NaBH4 flow rate, 1.5 mL min(-1); carrier gas flow rate, 0.8 L min(-1) and concentration of HCl, 8 mol L(-1). A study to verify a possible interference of Ni under the optimized conditions for vapor generation revealed that this interference does not affect the determination of As, Sb and Se when employing HCl 8 mol L(-1). Therefore, crude oil and biodiesel samples were analyzed at the previously optimized conditions. Only As and Se were detected in crude oil samples, while the concentrations of these analytes in the biodiesel samples were always lower than the obtained LODs. Although, the recovery for the Sb additions in biodiesel and crude oil samples were in a large range, between 72% and 111%, indicating that HCl is not the most efficient pre-reducer for this element, it can be said that, for multielemental analysis whose objective is to evaluate the presence of this element or a possible contamination by it, this prereducer can be employed.
Wu, Debo [Verfasser], Thomas [Akademischer Betreuer] Pichler, and Andrea [Akademischer Betreuer] Koschinsky. "Optimization of methodology for the simultaneous speciation of inorganic As, Sb and Se in fluid samples by sector-field ICP-MS coupled to HPLC / Debo Wu. Gutachter: Thomas Pichler ; Andrea Koschinsky. Betreuer: Thomas Pichler." Bremen : Staats- und Universitätsbibliothek Bremen, 2015. http://d-nb.info/1075609313/34.
Full textČernohorský, Jan. "Řízení provozu IT v modelu MBI se zaměřením na prostředí středních škol." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-193928.
Full textHsiung, Chih-Chun, and 熊志鈞. "Phase equilibria of Bi-Se-Sb thermoelectric materials at 300 ℃." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/57786073726002771246.
Full text國立東華大學
材料科學與工程學系
103
The ternary Bi-Se-Sb system has a great attention to the thermoelectric materials due to its properties. However, only few phase diagram information is available for this ternary system. The 300℃ isothermal section of the ternary Bi-Se-Sb system is experimentally determined in this study. Forty samples were prepared by annealing at 300℃ for three months. The equilibrium isothermal section was experimentally determined based on simple analysis.
Yu, Chia-Hua, and 于家驊. "Research of synthesizing Sb-S-Se quantum dot in ion exchange method." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/53503017368952920987.
Full text國立中興大學
物理學系所
105
Nowadays, Hydrothermal method and Chemical Beth Deposition method are the most widely synthesis methods to fabricate Antimony Triselenide (Sb2Se3) quantum dots. However we try a new way that no one has done it before . At first, we synthesize the Antimony Sulfide on the surface of TiO2 particles in Successive Ionic Layer Adsorption And Reaction(SILAR) method. After SILAR procedure, dip the cell into the selenium solution with NaBH4 precursor to process ion exchange immediately. The selenide quantum dots will form after 300 ℃ annealing procedure and make it forming the Sb2S(3-x)Se(x)(0≦x≦3) type quantum dots sensitized solar cell (QDSSC) eventually. For the Sb2S3 QDSSC, the efficiency is 1.13% , the Voc is 0.41V,the Isc is 5.46 mA/cm2 and the Fill Factor is 50.5% with the Pt counter electrode and Polyiodide electrolyte. Compare to Sb2S3 QDSSC, we got poor performance in the selenide QDSSC. We recorded the best that efficiency is 0.104% ,the Voc is 0.29 V ,Isc is 0.64 mA/cm2 and FF is 55.82%. Though we fail to make higher performance QDSSC in the Sb-S-Se form, we developed a new method to synthesize selenide quantum dots. According to the XRD and EDAX analyses, we can prove that the semiconductor quantum dots of different S/Se ratio can be formed in different ion exchange time. If we can find another oxidant instead of NaBH4, we could have the chance to make Sb-S-Se quantum dots successfully in the future.
Shen, Jun. "Untersuchungen in ternären chalkogenhaltigen Systemen Ag-Ga-Te und Sn-Sb-Se." Doctoral thesis, 2003. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-2003021919.
Full textLin, Kuo-Yang, and 林國揚. "X-ray absorption spectroscopy study of Sb and Se doped Bi2Te3 powders." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/21255099092020964423.
Full text淡江大學
物理學系碩士班
96
In order to study the correlation between doping effect and the thermoelectric property, we have performed x-ray absorption near-edge structure (XANES) study on a series of thermoelectric materials of Bi2-xSbxTe3(x=0,0.5, 1.0 and 1.5) and Bi2Te2.7Se0.3 powders. In the Sb-doped systems, according to the result of the thermopower measurement we found different types of carrier appeared when doping different concentration of Sb. The XANES spectra show that in both p-type and n-type samples, carriers are increased in Sb-doped systems, and decreased in Se-doped systems. After comparing the result of XANES and resistivity measurement, it shows that the resistivity is positively related to the concentration of the carriers when doping Sb; however, the resistivity is negatively related to the concentration of the carriers when doping Se. As a result, any substitution in either Bi-site or Te-site will likely have negative effects on the carrier mobilities.
PÚČKOVÁ, Kamila. "Podpora státu osobám se zdravotním postižením podle zákona č. 329/2011 Sb." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-398947.
Full textHuang, Hsin-Chieh, and 黃歆傑. "Synthesis and Characterization of Novel Ternary Polyselenides Ba-M’-Se (M’ = Sn, Sb)." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/6mzynj.
Full text國立交通大學
應用化學系碩博士班
104
Two novel ternary polyselenides, Ba7Sn2Se14 and Ba3Sb2Se7 were synthesized by solid-state reaction. They crystallize in new structure types, and both have Se-Se bonds. The products were characterized, and the structures were determined. In addition, we did the measurements of physical properties. Besides, we also discovered a potential of unknown in Eu/Sr-Si-Cu-Se system. Ba7Sn2Se14 was synthesized at 1,123 K. It crystallizes in the monoclinic space group Cm. The structure is constructed of SnSe4 tetrahedra, Se22- diselenides and Ba2+ cations. Measurements of physical properties indicate the semiconducting behavior, and theoretical calculations stand for it. Ba3Sb2Se7 was synthesized at 1,023 K. It crystallizes in the orthorhombic space group Cmcm. The structure is constructed of Sb4Se1412- units, and Ba2+ cations isolate the units. The basic unit Sb4Se1412- is constructed of two SbSe4 seesaws and two SbSe5 seesaws. Four seesaws connect alternately in corner-sharing to form a quadrilateral unit. Measurements of physical properties indicate the semiconducting behavior, and theoretical calculations stand for it. Furthermore, we also discussed the possibility of Ba3Sb2Se7+x (x = 0 – 0.5).
Hsu, Chia-Che, and 許嘉哲. "The Recording Layer Study of Ag-In-Sb-Se Phase Change Optical Disk." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/32013712891078022595.
Full textHolejšovská, Kateřina. "Vlastnictví bytu a nebytových prostor v souvislosti se zákonem č. 72/1994 Sb." Master's thesis, 2011. http://www.nusl.cz/ntk/nusl-300249.
Full textChen, Hsin-Yi, and 陳心怡. "Study of the Properties of Ge-Sb-Se-Sn Arsenic-Free Infrared Transmitting Glasses." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/89502209543837630278.
Full textChang, Shih Jen, and 張士仁. "The Analysis of As, Sb and Se in Air Particulates by ETV-ICP-MS." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/23090231411638281201.
Full textEndaisha, El-Abbas Ahmed Mohamed. "First principle calculations for Topological Insulators: the (Sb, Bi)2 (Se, Te)3 compounds." Master's thesis, 2017. http://hdl.handle.net/10316/82972.
Full textNos últimos anos, a pesquisa sobre propriedades de isoladores topológicos tem sido um campo muito ativo. Devido às suas propriedades eletrônicas únicas, esses materiais são fortes candidatos para muitas aplicações em spintronics. Esta tese visa investigar as propriedades eletrônicas dos compostos da família (Bi, Sb)_ 2 (Se, Te) _ 3 usando cálculos de primeiros princípios. O efeito de spin-Hall quântico e os isoladores topológicos são discutidos. São aplicadas duas abordagens de DFT ̶ pseudopotential e LAPW. Os cálculos foram realizados utilizando Quantum ESPRESSO e WIEN2k. Foram calculadas algumas propriedades a granel dos materiais (Bi, Sb) _2 (Se, Te) _3. Os estados de superfície calculados para (Bi_2 Se) _3, (Bi_2 T) _3 e (Sb_2 Te) _3. Os resultados confirmaram o comportamento topológico desses materiais. Devido à influência do acoplamento spin-orbital, observaram-se os estados de borda helicoidal. Os resultados também mostraram que a abordagem pseudopotencial é comparável ao LAPW para calcular a estrutura da banda e a densidade dos estados.Nos últimos anos, a pesquisa sobre propriedades de isoladores topológicos tem sido um campo muito ativo. Devido às suas propriedades eletrônicas únicas, esses materiais são fortes candidatos para muitas aplicações em spintronics. Esta tese visa investigar as propriedades eletrônicas dos compostos da família (Bi, Sb) _ 2 (Se, Te) _ 3 usando cálculos de primeiros princípios. O efeito de spin-Hall quântico e os isoladores topológicos são discutidos. São aplicadas duas abordagens de DFT ̶ pseudopotential e LAPW. Os cálculos foram realizados utilizando Quantum ESPRESSO e WIEN2k. Foram calculadas algumas propriedades a granel dos materiais (Bi, Sb) _2 (Se, Te) _3. Os estados de superfície calculados para Bi_2 Se _3, Bi_2 Te _3 e Sb_2 Te _3. Os resultados confirmaram o comportamento topológico desses materiais. Devido à influência do acoplamento spin-orbital, observaram-se os estados de borda helicoidal. Os resultados também mostraram que a abordagem pseudopotencial é comparável ao LAPW para calcular a estrutura da banda e a densidade dos estados.
In recent years, the research on properties of topological insulators has been a very active field. Due to their unique electronic properties, these materials are strong candidates for many applications in spintronics. This thesis aims to investigate the electronic properties of (Bi,Sb)_2 (Se,Te)_3 family compounds using first-principles calculations. The quantum spin-Hall effect and the topological insulators are discussed. Two approaches of DFT ̶ pseudopotential and LAPW are applied. The calculations were carried out using Quantum ESPRESSO and WIEN2k. Some bulk properties of (Bi,Sb)_2 (Se,Te)_3 materials were calculated. Surface states calculated for Bi_2 Se_3, Bi_2 Te_3 and Sb_2 Te_3. The results confirmed the topological behavior of these materials. Because of the influence of spin-orbit coupling, the helical edge states were observed. The results also showed that the pseudopotential approach is comparable to LAPW in order to calculate the band structure and density of states.In recent years, the research on properties of topological insulators has been a very active field. Due to their unique electronic properties, these materials are strong candidates for many applications in spintronics. This thesis aims to investigate the electronic properties of (Bi,Sb)_2 (Se,Te)_3 family compounds using first-principles calculations. The quantum spin-Hall effect and the topological insulators are discussed. Two approaches of DFT ̶ pseudopotential and LAPW are applied. The calculations were carried out using Quantum ESPRESSO and WIEN2k. Some bulk properties of (Bi,Sb)_2 (Se,Te)_3 materials were calculated. Surface states calculated for Bi_2 Se_3, Bi_2 Te_3 and Sb_2 Te_3. The results confirmed the topological behavior of these materials. Because of the influence of spin-orbit coupling, the helical edge states were observed. The results also showed that the pseudopotential approach is comparable to LAPW in order to calculate the band structure and density of states.
Lee, Chien-He, and 李健和. "Synthesis and Characterization of New Ternary Selenides Homologous Series in Ge-Sb-Se System." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/dg43d5.
Full text張莨鈞. "Liquidus projections of the Se-Sb-Te ternary thermoelectric material system and the Ag-In-Se ternary solar energy material system." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/99501915147636745847.
Full textHsu, Yu-Lan, and 許宇嵐. "Determination of Ge,As,Se,Sb in water and urine samples by ICP-DRC-MS." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/11527148304190479030.
Full textWu, Chih-yu, and 吳芷聿. "Interfacial reactions between Sn, Ni and (Bi,Sb)2Te3, Bi2(Te,Se)3 thermoelectric materials." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/45699685338527106798.
Full text國立清華大學
化學工程學系
101
(Bi1-xSbx)2Te3 and Bi2(Te1-ySey)3 are common thermoelectric materials. In the manufacturing of thermoelectric device, Sn is the major element for most of the electronic solders, and Ni is used as diffusion barrier. The interfacial reactions between Sn, Ni and (Bi1-xSbx)2Te3, Bi2(Te1-ySey)3 thermoelectric materials will be investigated in this study. The interfacial reactions at 250 oC in the Sn/(Bi0.25Sb0.75)2Te3 and Sn/Sb2Te3 couples are examined. The initial reaction product only has one phase, and is SnTe phase with small pores which are filled with liquid. With longer reaction time, the small liquid droplets connect together and form periodic liquid layer in the reaction zone. The liquid layer, which is primarily molten Sn, further reacts with Sb, and a self-assembled Sn3Sb2/SnTe alternating layer is found in the couples. Bi precipitates are found as well in the reaction zone in the Sn/(Bi0.25Sb0.75)2Te3 couples in the later stage of reactions. In Sn/Bi2(Te0.9Se0.1)3 couple, it formed SnTe, Bi6Te7, and BiTe phase. Sn/Bi2Se3 couple formed SnSe and BiSe phase. In Sn/Bi2Te3, the interfacial reaction rate is fast, and the growth rate is about 59 μm/min. It formed a irregular SnTe + Liquid phase. The amount of Se in Bi2(Te0.9Se0.1)3 substrate is only 6%, but it’s growth rate and intermetallic compound are very different compared with Sn/Bi2Te3 couple. The Ni/(Bi0.25Sb0.75)2Te3 and Ni/Bi2(Te0.9Se0.1)3 couples both formed NiTe phase, and Ni/Bi2(Te0.9Se0.1)3 also formed BiTe phase. Ni penetrates deeper in Bi2(Te0.9Se0.1)3 substrate. The fast diffusion rate may cause failure or lower the efficiency in thermoelectric device.
Chen, Yi-Syuan, and 陳逸軒. "Dual-beam pulsed laser deposition of Cu-Sb-Se/Sb2Se3 nanocomposite films for thermoelectric applications." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/46m83v.
Full textShen, Jun [Verfasser]. "Untersuchungen in ternären chalkogenhaltigen Systemen Ag-Ga-Te und Sn-Sb-Se / eingereicht von Jun Shen." 2001. http://d-nb.info/97038033X/34.
Full textChiu, Chen-nam, and 邱政男. "Phase equilibria and interfacial reactions of Sn-Bi-Sb-Te and Sn-Bi-Te-Se systems." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/32340004747754457127.
Full textKováčová, Pavlína. "Dopady novely zákona č. 435/2004 Sb., o zaměstnanosti se zaměřením na zaměstnávání zdravotně postižených osob." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-169067.
Full textChung, Kyung-Min [Verfasser]. "Sn-Sb-Se based binary and ternary alloys for phase change memory applications / vorgelegt von Kyung-Min Chung." 2008. http://d-nb.info/991290062/34.
Full textYang, Ting-ruei, and 楊庭瑞. "Interfacial reactions between Ni barrier layer and thermoelectric substrates: Ag2Te, (Bi,Sb)2Te3, and Bi2(Te,Se)3." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/72675320497357823558.
Full text國立清華大學
化學工程學系
103
Thermoelectric devices can convert heat into electricity directly, and have attracted enormous research interests. There are usually numerous solder (or braze) joints in thermoelectric devices. To prevent direct contact and interfacial reactions between solder (or braze) and thermoelectric materials, barrier layer is often used. Ni is the most commonly used barrier layer material. Examination of the interfacial reactions between Ni and thermoelectric substrates is fundamentally important for reliability assessment of the thermoelectric devices. This study investigates interfacial reactions between Ni and three kinds of thermoelectric materials: Ag2Te, (Bi,Sb)2Te3, and Bi2(Te,Se)3. The thermoelectric substrates are prepared with proper amounts of pure constituent elements, and are then plated with Ni. The thickness of Ni layer is 60μm. Ni3Te2, NiTe0.775 and NiTe2 are formed in the Ni/Te couple reacted at 200oC for 720 hours. Two reaction regions are observed in the Ni/Ag2Te couple reacted at 200oC for 720 hours. A continuous Ag layer is formed adjacent to the Ni substrate. The other reaction region is a two-phase finger-type mixture. The darker phase in this two-phase region is the Ni3Te2 phase and the other brighter phase is Ag2Te phase with Ni solubility. This study also investigates the interfacial reactions between Ni/Te couple and Ag2Te couple at 250 oC. Ni3Te2, NiTe0.775 and NiTe2 are also formed in the Ni/Te couple reacted at 250oC for 720 hours, and the thickness of reaction layer is about 102.6μm. Two reaction regions are observed in the Ni/Ag2Te couple reacted at 250oC for 720 hours. A continuous Ag layer is formed adjacent to the Ni substrate. Comparing with those in the Ni/Ag2Te 200oC reaction couple, a continuous Ni3Te2 reaction layer is formed adjacent to the Ag2Te substrate. The interfacial reactions between the Ni barrier layer and the P-type (Bi1-xSbx)2Te3 and n-type Bi2(Te1-ySey)3 thermoelectric materials at 300oC are examined. Two reaction phase layers are observed in the Ni/(Bi0.25Sb0.75)2Te3 couples reacted at 300oC. The phase layer adjacent to the Ni substrate is likely a Sb-Ni-Te ternary compound or the Ni3Te2 phase with significant Sb solubility.In the In the Ni/ Bi2(Te0.9Se0.1)3 couple reacted at 300oC two reaction phase layers are also found. The BiTe phase is adjacent to the Bi2(Te0.9Se0.1) substrate, while a Bi-Ni-Te ternary compound or the NiTe2 phase with Bi solubility is formed adjacent to the Ni substrate. It can be found that the thickness of the reaction layers in the Ni/Bi2(Te0.9Se0.1)3 couple is thicker than that in the Ni/(Bi0.25Sb0.75)2Te3. Furthermore, the reaction rate at 300oC is faster than that at 250oC.
ŽEBROVÁ, Ivana. "Změny ve využívání terénních služeb pro seniory ve Středočeském kraji v souvislosti se zákonem č. 108/2006 Sb." Master's thesis, 2009. http://www.nusl.cz/ntk/nusl-49992.
Full textHuang, Yao-Hung, and 黃耀弘. "Study of Novel Cu-Sb-Se Thin Film by Non-vacuum Solvothermal Refluxing Method with Polyetheramine as Solvent." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/67785201141210644516.
Full text國立臺南大學
電機工程學系碩博士班
105
Abstract: This paper studies the novel semiconductor materials Cu-Sb-Se. The copper-based ternary chalcogenide thin films Cu3SbSe4 (CASe) were prepared by a simple and low-cost non-vacuum technology-Solvothermal Refluxing Method. The copper, antimony and selenium powder with stoichiometric ratio of 3: 1: 4 were added into the novel organic solvent D400 (polyetheramine) and selenized at the temperature are 180℃, 220℃, 250℃ for 1 hour, 15 hours and 30 hours, respectively. The nano-inks were also discussed and analyzed for its structural phase, surface morphology, composition and optical properties. Finally, we have found that a single ternary pure phase Cu3SbSe4 film with a tetragonal crystal structure can be successfully obtained at 250℃ for 30 hours, which has good crystallinity. This can be effectively used as a thermoelectric material in thermoelectric devices. We used Solvothermal Refluxing Method to synthesize nano-inks at low temperature for a short period of time and then selenization process in an atmosphere filled with selenium. The selenization temperatures range are from 300℃ to 625℃ and the selenization times are from 0 minute to 90 minutes. By observing the phase changes in different stages with temperature and time changes to understand the reaction mechanism of Cu, Sb, Se and D400 (polyetheramine), and further deduces CASe particle growth mechanism. The results of the electrical properties of the CASe films after the selenization process showed that the P-type semiconductor film. The carrier mobility was 4.76×101 cm2/V-s, the carrier concentration was 3.11×1016 cm-3. In the future work, use the Solvothermal Refluxing Method can be a large number of manufacturing CASe films, after selenization process can improve its crystallinity, and widely application in thermoelectric devices.
Shih-TingTu and 杜詩婷. "Electrodeposition of binary and ternary Cu-Sb-Se thin films and study of annealing temperature for light absorption." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ps7mew.
Full textJiang, Cing-Ru, and 蔣青儒. "Ion exchange-prepared Pb-Sb-Se nanoparticles: A new solar absorber material for quantum dot-sensitized solar cells." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/s6emey.
Full text國立中興大學
奈米科學研究所
106
This thesis describes the new ternary semiconductor sensitizer lead antimony selenide (Pb-Sb-Se) for solar cells. Pb-Sb-Se nanoparticles (NPs) have been prepared from a lead antimony sulfide (Pb-Sb-S) precursor by the solution-based Se2- anion exchange reaction. The Pb-Sb-S precursor was grown on a mesoporous TiO2 electrode using the successive ionic layer adsorption and reaction (SILAR) process. To analyze the property the as-prepared materials were characterized by UV-Visible, X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). XRD shows that the synthesized Pb-Sb-Se NPs have the same crystal structure as the Pb-Sb-S precursor with the diffraction angles significantly down-shifted around 0.8-1.3˚. Energy-dispersive X-ray spectroscopy (EDS) confirms the complete anion exchange from Pb-Sb-S and formation of the Pb-Sb-Se phase. UV-visible spectroscopy reveals the Pb-Sb-Se NPs optical energy gap (Eg) to be ~ 1.45 eV that is lower than the Pb-Sb-S precursor (~1.75 eV). Liquid-junction semiconductor-sensitized solar cells were fabricated from the synthesized Pb-Sb-Se semiconductor with polysulfide electrolyte and Pt electrode as counter electrode. The best cell yields a short-circuit current (Jsc) of 8.3 mA/cm2, an open circuit voltage (Voc) of 0.3 V, a fill factor (FF) of 32.8 %, and a power conversion efficiency (PCE) of 1.15 % (one sun) and 4.18 % (10 % sun), respectively.
Chanh, Jui Shen, and 張睿紳. "Phase equilibria and phase transformations of Sb-Se-Pb-Sn thermoelectric materials and Sn-Ag-In-Zn electronic solders." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3dk6p3.
Full text國立清華大學
化學工程學系
105
Thermoelectric materials and devices are regarded as the important energy materials have been the subject of intensive study, primarily because of their abilities of direct transformation between heat and electricity. Recently, due to the development of advanced semiconductor processes and nanotechnology, the researches of thermoelectric materials are moving into new territory. Lead telluride (PbTe) and Cobalt triantimonide (CoSb3) alloys are the most widely used mid-temperature thermoelectric materials. Additionally, the Sb-Se-Pb-Sn alloys have been recently examined among various promising thermoelectric materials. In Sb-Se-Pb-Sn system, the PbSe, Sb2Se3 and SnSe compounds are of interests to thermoelectric applications because of their outstanding performances reported by numerous groups. Soldering plays an important role of assembly of thermoelectric devices. Sn-Pb alloys are the preferred jointing material of electronic industry owning to its attractive price and relative low melting point. Nevertheless, there are healthy and environmental issues associated with the toxicity of Pb containing solders, the researches of Pb-free solders were taken seriously. In a variety of Pb-free solder systems, Sn-Ag-Cu alloys are used widely. Besides, Sn-Ag-In, Sn-Ag-Zn, and Sn-In-Zn solder alloys are also promising Pb-free solders. Additionally, there are studies about using Sn-Ag-In-Zn quaternary alloys as electronic solders. Construction of Sn-Ag-In-Zn system is fundamentally important for designing the solder alloys with better mechanical properties and higher stability. However, the phase diagrams and thermodynamic models of Ag-In-Zn ternary system have not been constructed. Knowledge of phase equilibria is fundamentally important for materials development and applications. Phase diagrams can be obtained by experimental determinations and calculations. The CALPHAD (Calculation of Phase Diagram) approach is the most popular calculation method. Based on the information of the thermodynamic properties and phase equilibria of system, the assessment of the thermodynamic models can be determined. In this study, the phase diagrams of Ag-In-Zn system of Sn-Ag-In-Zn quaternary system and Pb-Sb-Se, and Sn-Sb-Se ternary systems of Sb-Se-Pb-Sn quaternary systems are determined. The microstructures, compositions, and diffraction peaks were determined using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), electron probe X-ray microanalyzer (EPMA) and X-ray diffractometer (XRD). A differential thermal analysis (DTA) was used to determine the reaction temperatures of the invariant reactions. The CALPHAD approach and AIMD (Ab-initio molecular dynamics) have been used for the assessment of the thermodynamic models of Sb-Se and Sn-Se binary systems. The liquidus projection and isothermal section of Ag-In-Zn lead-free solder system and Pb-Sb-Se, Sn-Sb-Se thermoelectric systems are experimentally determined. There are 10 primary solidification phases: (Ag), (In), (Zn), Beta-(Ag3In), Zeta-(Ag3In), Gamma-(Ag9In4), AgIn2, Beta-(AgZn), Gamma-(Ag5Zn8), and Epsilon-(AgZn3) in the Ag-In-Zn ternary system. Moreover, there are five ternary invariant reactions: Liquid=(In)+AgIn2+Gamma-(Ag5Zn8), Liquid=Epsilon-(AgZn3)+(In)+(Zn), Liquid+Beta-(AgZn)=Gamma-(Ag5Zn8)+Gamma-(Ag9In4), Liquid+Zeta-(Ag3In)=Gamma-(Ag5In8)Beta-(AgZn) and Liquid+(Ag)+Beta-(AgZn)=Zeta-(Ag3In). In the isothermal section at 500oC, there is no ternary compound and there are 6 tie triangles : (Ag)+Zeta-(Ag3In)+Beta-(AgZn), Zeta-(Ag3In)+Gamma-(Ag9In4)+Beta-(AgZn), Zeta-(Ag3In)+Gamma-(Ag9In4)+Liquid, Gamma-(Ag9In4)+Beta-(AgZn)+Liquid, Beta-(AgZn)+Gamma-(Ag5Zn8)+Liquid and Gamma-(Ag5Zn8)+Epsilon-(AgZn3) in the 500oC isothermal section of Ag-In-Zn ternary system. There are 8 primary solidification phases, which are (Pb), (Sb), (Se), PbSe, Sb2Se3, Pb6Sb6Se17, PbSb2Se4 and Pb2Sb9Se9 phases in the liquidus projection of Pb-Sb-Se ternary system. Among of all the primary solidification phases, the ternary compound, Pb2Sb9Se9 is the new ternary compound which has not been reported before. The XRD pattern of Pb2Sb9Se9 is determined by X-ray diffraction analysis. Furthermore, Five invariant reactions: Liquid=PbSe+(Sb)+(Pb), Liquid=Pb2Sb9Se9+PbSb2Se4+Sb2Se3, Liquid+(Sb)=Pb2Sb9Se9+Sb2Se3, Liquid +PbSe =PbSb2Se4+Pb2Sb9Se9, Liquid+PbSe+(Sb)=Pb2Sb9Se9 are determined by thermal analysis. There are 9 tie-triangles, which are PbSe+(Sb)+Liquid, PbSe+PbSb2Se4+(Sb), PbSb2Se4+Pb2Sb9Se9+(Sb), PbSb2Se4+Pb2Sb9Se9+Sb2Se3, Pb2Sb9Se9+Sb2Se3+(Sb), PbSe+Pb6Sb6Se17+PbSb2Se4, PbSe+Pb6Sb6Se17+Liquid, Pb6Sb6Se17+PbSb2Se4+Sb2Se3 and Pb6Sb6Se17+Sb2Se3+Liquid, in the 400oC isothermal section of Pb-Sb-Se ternary system. There are 10 primary solidification phases, which are (Sn), (Sb), (Se), Sb2Sn3, SbSn, SnSe, SnSe2, Sb2Se3, Sn2Sb9Se9 and SnSb2Se4 phases in the liquidus projection of Sn-Sb-Se ternary system. It is worthy of mentioning that Sn2Sb9Se9 ternary phase is another new compound which has not been reported in the literature. The XRD pattern of Sn2Sb9Se9 is determined by X-ray diffraction analysis. Seven invariant reactions: Liquid+Sb2Sn3=SnSe+(Sn), Liquid+SbSn=SnSe+Sb2Sn3, Liquid+(Sb)=SbSn+SnSe, Liquid+Sn2Sb9Se9=SnSb2Se4+Sb2Se3, Liquid+Sn2Sb9Se9+(Sb)=Sb2Se3, Liquid+(Sb)+SnSe=Sn2Sb9Se9 and Liquid+Sn2Sb9Se9+SnSe=SnSb2Se4 are experimentally determined in this study. There are 9 tie-triangles, which are Liquid+SbSn+SnSe, SbSn+SnSe+(Sb), SnSe+(Sb)+Sn2Sb9Se9, (Sb)+Sb2Se3+Sn2Sb9Se9, SnSe+Sn2Sb9Se9+SnSb2Se4, Sb2Se3+Sn2Sb9Se9+SnSb2Se4, SnSe+SnSe2+SnSb2Se4, SnSe2+SnSb2Se4+Sb2Se3 and SnSe2+Sb2Se3+Liquid, in the 400oC isothermal section of Sn-Sb-Se ternary system. In the calculation of Sb-Se binary system, the functions of Gibbs energies of pure elements are taken from SGTE database, and the associate model is used to describe the liquid phase. The new thermodynamic description of the Sb–Se system is proposed, and good agreement between available literature data and calculated results is found. The re-optimized thermodynamic model of Sb-Se binary system may allow the construction of calculations upon multicomponent. Another important investigation in this study is examining the existence of miscibility gap of Sn-Se binary system by using AIMD simulations. The enthalpy of mixing in liquid phase is calculated, and the results are fitted with Redlich-Kister polynomial for obtaining the new parameters used in CALPHAD approach.
Kotlár, Martin. "Nabývání vlastnictví k nemovitostem (zejména k jednotkám dle zákona č. 72/1994 Sb.), se zvláštním zřetelem k nabývání vlastnictví k jednotkám cizozemci." Master's thesis, 2008. http://www.nusl.cz/ntk/nusl-288153.
Full textNi, Jun-Long, and 倪俊龍. "Determination of Ga,Ge,As,Se and Sb in coal fly ash and S and Pb in gasoline by inductively coupled plasma mass spectrometry." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/43591702728253410756.
Full textVien, Steve Hung. "Sensitivity enhancement and interference studies in ultra-trace As, Se, Sb, and Sn determination by hydride generation atomic absorption and a new Tenax GC." 1986. http://hdl.handle.net/2097/22167.
Full textLiou, Kuen-Ming, and 劉昆明. "Effect of electric current assisted thermal treatments on transport properties and defect elimination in sputtered Bi−Sb−Te and Bi−Se−Te thermoelectric thin films." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/66259618600788446873.
Full text國立清華大學
材料科學工程學系
98
Recently, environmental crisis spurs the researches on alternative energy and hence thermoelectric materials, which can convert heat into electricity, or alternatively, convert electricity into cooling, attract renewed attention. Due to the advantages of high cooling power density and short response time, thin-film thermoelectric coolers (TECs) have been considered as the plausible solution to the thermal management problem of microelectronics. Bismuth telluride based compounds are known to be the best thermoelectric materials near room temperature regime to date and are the potential candidates for thin-film TECs. A post-deposition thermal treatment is usually used to reduce the structural imperfections and improve thermoelectric properties of bismuth telluride based thin films prepared by physical vapor deposition and electrochemical deposition methods. Recently, spark plasma sintering (SPS) technique, using electric energy as the heat source, was demonstrated to be very effective in the rapid densification of bismuth telluride based powder materials. The SPS-prepared bismuth telluride based compounds have dense, textured and polycrystalline microstructures, and most important of all, excellent thermoelectric properties. Nevertheless, the details of how an electric current interacts with bismuth telluride compounds are still not fully understood. In this study, p-type Bi-Sb-Te and n-type Bi-Se-Te nanocrystalline films were prepared by a r.f. magnetron sputtering method followed by a electrical annealing process. An electric current of density ~ A/cm2 was introduced through films during thermal annealing. The electrically stressed p- and n-type films were found to have lower carrier concentration but much higher mobility than those thermally annealed at the same temperatures. A model based on electromigration-induced preferential Sb and Te diffusion is proposed to explain the observed Sb-rich and Te precipitation as well as the enhancement of Seebeck coefficient and electrical conductivity of the electrically stressed thin films. Owing to anisotropic diffusion and electrical transport properties, charged lattice defects in the (00l) grains of bismuth telluride crystal are preferentially eliminated under electric current stressing. The presented current-assisted annealing approach can be an efficient post-deposition treatment in a short cycle time and low temperature that prevents from unfavorable gross grain growth and evaporation of volatile constituents in Bi-Te based nanocrystalline thin films during high-temperature annealing process.
Chang, Wei-Chieh, and 張惟傑. "Group 15 (Sb, Bi) Containing Mixed Transition Metal (Cr, Fe) Carbonyl Complexes and EFe3Hg (E = S, Se, Te) Cluster-based Cation-anion Cu Polymers: Synthesis, Reactivities, and Physical Properties." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/7279xm.
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