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Holt, Jim, i Gregg Mitchell. "SAMS Work Group—Preventive Care". Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/6466.
Pełny tekst źródłaPrompinit, Panida. "Formation and application of photo-patterned SAMs". Thesis, University of Leeds, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539684.
Pełny tekst źródłaYousefalhaj, Nisreen. "Molecular engineering of azidoorganosilane-based SAMs for bioapplications". Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0317.
Pełny tekst źródłaThe ability to control surface properties and produce molecularly engineered SAMs is the key aspect for a precise biomolecules immobilisation in a preferred manner, which is of major importance for the development of many bioapplications. In this work, we provide first the novel synthesis of different types of coupling agents used to provide two types of azide-terminated SAMs: bearing an alkyl spacer or a urea spacer of different lengths. Then, we present in details the deposition of SAMs by using different methods and strategies in different solvents. Each change has been deeply studied to investigate its effect on the organic matter within the SAMs and the azide orientation, as well as the reactivity of the azido group towards the click reactions (CuAAC). The chemical modifications of the surfaces have been investigated by the PM-IRRAS, XPS, AFM and the contact angle measurements. Thus, this work ends up with a relatively big list of well-defined azide-terminated SAMs, as good candidates for various bioapplications. Some of azide-terminated SAMs have been successfully used to immobilise GNLs, resulting in differences of immobilised GNLs quantity on the surface depending on the nature of SAMs and the quantity of azide groups. This platform shows promising results when tested for stem cells culture
Cheadle, Edward Martin. "Characterisation of self-assembled monolayers". Thesis, University of Leeds, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250878.
Pełny tekst źródłaRibeiro, Luisa Maria Fialho. "Qualidade dos cuidados de enfermagem no hospital dos SAMS". Master's thesis, [s.n.], 2012. http://hdl.handle.net/10400.26/16142.
Pełny tekst źródłaNa identificação que o Plano Nacional de Saúde 2012-2016 faz da situação atual quanto à qualidade em saúde, e à semelhança do Plano anterior, identifica uma escassa cultura de qualidade associada a um défice organizacional dos serviços de saúde, assim como a falta de indicadores de desempenho e de apoio à decisão. A implementação de sistemas de melhoria contínua da qualidade torna-se assim fundamental. Com a qualidade enquanto core de uma organização de saúde, cabe ao enfermeiro chefe, enquanto gestor de enfermagem, munir-se dos instrumentos adequados e incrementar estratégias favorecedoras de um melhor nível de desempenho e responsabilidade profissional, com direta repercussão nos ganhos em saúde resultantes do cuidado de enfermagem. Objetivo: Com a realização deste Projeto de Intervenção pretendeu-se desencadear a implementação de um Sistema de Melhoria Contínua da Qualidade no Departamento de Cirurgia do Hospital dos SAMS. Metodologia: Para a consecução do presente trabalho, socorremo-nos da Metodologia de Trabalho de Projeto, e de um documento produzido pela Ordem dos Enfermeiros em 2010, - Regulamento da Idoneidade Formativa dos Contextos de Prática Clínica, que compreende sete dimensões de análise, à luz do qual foi feita a análise das práticas do Departamento de Cirurgia do Hospital dos SAMS. Da aplicação do referido documento, resultou uma grelha – grelha de análise – na qual, são evidenciadas as dimensões suscetíveis de intervenção. Resultados: Ao nível organizacional, foi envolvida a gestão de topo (Enfermeiro Supervisor), no sentido da necessidade de conceber um documento ancorador das práticas de enfermagem. Sustentados na literatura; no coaching obtido de instituições análogas e, ainda, em documentação interna, foi desenvolvido o Quadro de Referência para o Hospital dos SAMS. Ao nível departamental, destacamos a realização do Quadro de Referência para o Departamento; mobilização da equipa para desenvolver e ampliar o âmbito da avaliação da qualidade dos cuidados a outros indicadores (Dor; Satisfação do Utente; Incidente Críticos); nomeação do Enfermeiro Responsável pela Formação em Serviço e do Enfermeiro de ligação ao PQCE, que se traduziu na realização de diversas formações, designadamente, no âmbito do PQCE e dos indicadores de qualidade anteriormente mencionados. Conclusões: Em termos gerais, a concretização do presente projeto, foi bastante proveitosa na medida em que, por um lado, despertou a gestão de topo para as questões da qualidade dos cuidados associadas às práticas de enfermagem. De outro, ao nível do departamento, possibilitou a reflexão da equipa sobre as práticas, tendo a mesma constituindo-se como móbil de alargamento do âmbito de intervenção a outras dimensões consideradas pertinentes, designadamente, enquadradas no PQCE e, ao nível das parcerias com as Escolas Superiores de Enfermagem/Saúde. Ao nível pessoal e enquanto gestora da Unidade de Saúde, a consecução deste projeto facilitou o desenvolvimento de “novas competências” que, associadas à motivação, se traduziram num olhar “mais crítico” acerca do nosso contexto profissional, impelindo-nos a intervir e mobilizar recursos no sentido de operar mudança numa área que nos preocupa muito – Qualidade dos Cuidados. Terminamos sublinhando o carácter desenvolvimentista e reformador da metodologia de trabalho de projeto, como ferramenta de intervenção nos contextos de trabalho.
Leonardi, Francesca <1986>. "Self-Assembled Monolayers (SAMs) in Organic Field-Effect Transistors". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6461/1/Leonardi__dottorato.pdf.
Pełny tekst źródłaLeonardi, Francesca <1986>. "Self-Assembled Monolayers (SAMs) in Organic Field-Effect Transistors". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6461/.
Pełny tekst źródłaPardo-Figuerez, Maria M. "Designing neuronal networks with chemically modified substrates : an improved approach to conventional in vitro neural systems". Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/27941.
Pełny tekst źródłaPukenas, Laurynas. "Fabrication and characterisation of SAMs for spin crossover and photocleavable surfaces". Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/16602/.
Pełny tekst źródłaBonin, Helena. "Fremde Kinder und ideologische Staatsapparate : Wie Momo, Pippi und das Sams Ideologie entgehen". Thesis, Högskolan Dalarna, Tyska, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:du-29356.
Pełny tekst źródłaGraybill, Elizabeth A. "Age, Origin and Mineral Resources of the Sams Creek/Wakefield Complex, Maryland Piedmont". Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1337975457.
Pełny tekst źródłaWang, Lian. "Synthesis and Characterization of Functionalized Bio-Molecular Surfaces with Self-Assembled Monolayers and Bioreactive Ligands for Nano/Biotechnological Applications". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195096.
Pełny tekst źródłaMarchante, Rodríguez Elena. "Self-assembled monolayers of electroactive molecules for the preparation of memory devices". Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/406091.
Pełny tekst źródłaThe ultimate goal of electrical circuits is miniaturization by using single molecules or collections of single molecules as electronic building blocks. It is expected that the smaller size of the electronic components will decrease the power consumption while increasing the sensitivity and the performance of the device. Research efforts are concentrated in two directions. The first one is focused in the study, at a fundamental level, of new molecules with specific properties or functionalities, which provides a deeper understanding of molecular structure, dynamics and reactivity. The second one is dedicated to develop new techniques for the implementation of these molecules in electronic devices. Often, to construct a molecular device it is necessary to deposit molecules or material on a suitable substrate. Since the ordering and packing of the molecules are crucial aspects for the operation of the devices, it is important to have a good control of how solvent, substrate or molecular functionalization influences on the resulting molecular assemblies and the intermolecular interactions. The present Doctoral Thesis is focused on the development of new molecular electronic devices based on electroactive self-assembled monolayers (SAMs), and on the electrochemical study of the electron transfer phenomena associated to them. In the first part of the Thesis, it is described the use of different redox molecules immobilized on gold substrates as molecular switches. The state of the electroactive compounds can be tuned when a specific potential is applied to the substrate, and the capacitance response has been successfully implemented as the read-out of the switch. It is important to highlight that these electrical molecular switches have been also obtained using ion gels as solid electrolytes, demonstrating the feasibility to integrate these systems in future electronic and/or flexible devices. In the second part of the Thesis, it is reported the electron transfer (ET) mechanism study, by electrochemical means, in a family of polychlorothriphenylmethyl radical (PTM) derivative compounds attached to gold substrates. The family of PTM molecules contains a thiol terminal group connected to the PTM through an alkyl chain with different lengths. It has been studied the ET process through PTM-SAMs in different organic electrolytic media and as a function of the surface coverage of the modified gold substrate. Hence, it was demonstrated that the interaction with the solvent plays an important role in the adiabaticity character of the redox process. Further, with neighbouring molecules, the intermolecular electronic coupling between PTM centers promotes a reduction of the ET constant rate. Finally, in the last part of the thesis, it has been fabricated a functioning OFET using an ion gel as gate dielectric, and its properties has been examined. The OFETs were prepared with top-gate and side-gate geometries, where the ion gel was placed on top of the substrate with the semiconductor channel. The ion gel gated OFET properties were compared with a reference OFET structure, which had a conventional SiO2 gate dielectric, demonstrating that the ion gels are highly attractive to be applied in low cost and flexible organic transistors.
Hou, Lin, Jaber Derakhshandeh, Silvia Armini, Carine Gerets, Preter Inge De, Rebibis Kenneth June, Andy Miller, wolf Ingrid De i Eric Beyne. "SAMs (self-assembled monolayers) passivation of cobalt microbumps for 3D stacking of Si chips". Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-207172.
Pełny tekst źródłaPinheiro, Solange de Oliveira. "Sintese , caracterizaÃÃo e eletroatividade de sams formadas com compostos catiÃnicos de tetraaminas de rutÃnio". Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1460.
Pełny tekst źródłaOs complexos trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+ (CNpy = 4-Cianopiridina, 1,4- dt = 1,4-ditiano), trans-[Ru(CNpy)(NH3)4(pyS)]2+ (pyS = 4-mercaptopiridina) e trans- [Ru(CNpy)(NH3)4(Tio)]2+ (Tio = tionicotinamida) foram sintetizados e caracterizados por Cromatografia LÃquida de Alta EficiÃncia, anÃlise elementar, eletroquÃmica e espectroscopias eletrÃnica e vibracional. Os espectros de absorÃÃo eletrÃnica e os resultados de eletroquÃmica evidenciaram uma interaÃÃo do tipo π back-bonding do centro metÃlico RuII para os ligantes piridÃnicos. Os valores dos potenciais formais de meia onda (E1/2) observados para os complexos trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+, trans-[Ru(CNpy)(NH3)4(pyS)]2+ e trans-[Ru(CNpy)(NH3)4(Tio)]2+: 1,00, 0,67 e 1,03 V vs ENH, respectivamente, indicam a estabilizaÃÃo do estado reduzido do centro metÃlico em relaÃÃo ao complexo de partida trans-[Ru(CNpy)(NH3)4(OH2)]2+ (E1/2 = 0,35 V vs ENH). Esse resultado indica, tambÃm, a forte capacidade π retiradora do ligante CNpy que, no caso do complexo trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+, à tÃo intensa que facilita comparativamente o processo de oxidaÃÃo do centro metÃlico. Podese concluir, portanto, que a capacidade π retiradora dos ligantes CNpy, pyS e Tio à similar. O deslocamento na freqÃÃncia de estiramento da ligaÃÃo C≡N do ligante Cnpy livre de 2239 para ∼2200 cm-1 apÃs coordenaÃÃo ao centro metÃlico [Ru(NH3)4]2+ nos espectros vibracionais indica que a coordenaÃÃo do ligante CNpy ocorre pelo grupamento nitrila. Para os ligantes pyS e Tio, a observaÃÃo das bandas atribuÃdas aos νC=S e νSH, respectivamente, indica que a coordenaÃÃo ocorre pelo Ãtomo de nitrogÃnio do anel piridÃnico. Os espectros SERS ex situ das superfÃcies modificadas com os compostos isolados permitem a classificaÃÃo destes como molÃculas modificadoras bifuncionais, onde o Ãtomo de enxofre dos ligantes pyS, 1,4-dt e Tio atuam como sÃtio de adsorÃÃo e o Ãtomo de nitrogÃnio piridÃnico do ligante CNpy atua como grupo funcional terminal. AlÃm disso, os resultados SERS sugerem uma conformaÃÃo trans para o complexo trans-[Ru(CNpy)(NH3)4(pyS)]2+ e gauche para os complexos trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+ e trans-[Ru(CNpy)(NH3)4(Tio)]2+ sobre ouro. A dependÃncia nas intensidades das bandas com o potencial aplicado aos eletrodos modificados ilustra o efeito π back-bonding dos Ãons metÃlicos dos adsorbatos inorgÃnicos, uma vez que observa-se uma relaÃÃo direta com os valores dos potenciais formais de meia onda dos complexos estudados. Os valores dos potenciais de dessorÃÃo redutiva observados para as SAMs dos complexos isolados refletem a capacidade π retiradora do ligante CNpy que se encontra na posiÃÃo para em relaÃÃo ao sÃtio de adsorÃÃo. Esse efeito à bem mais intenso no complexo trans- [Ru(CNpy)(NH3)4(1,4-dt)]2+, uma vez que a capacidade de interaÃÃo π back-bonding do ligante 1,4-dt à significativamente menor que as dos ligantes pyS e Tio. Sugere-se, para esse complexo, uma oxidaÃÃo parcial do centro metÃlico o que implica em uma intensificaÃÃo da interaÃÃo σ com o ligante 1,4-dt (RuII-S) e, conseqÃentemente, um enfraquecimento da ligaÃÃo Au-S. A reaÃÃo hTE da metaloproteÃna cyt c foi observada em valor consistente com seu estado in natura indicando que as SAMs estudadas acessam satisfatoriamente o processo hTE do cyt c alÃm de evitar a desnaturaÃÃo desta proteÃna. A forma das curvas voltamÃtricas, entretanto, apresentou uma dependÃncia com a configuraÃÃo dos complexos sobre a superfÃcie. Curvas de melhor definiÃÃo foram obtidas com a SAM do complexo trans-[Ru(CNpy)(NH3)4(pyS)]2+ que apresenta uma configuraÃÃo trans em relaÃÃo à superfÃcie.
Trans-[Ru(CNpy)(NH3)4(L)]2+ type complexes, where CNpy (4- Cyanopyridine), L= 1,4-dt (1,4-dithiane), pyS (4-mercaptopyridine), and Tio (thionicotinamide), were synthesized and characterized by HPLC, microanalysis, eletrochemistry and vibrational and eletronic spectroscopies. The eletrochemical and eletronic absorption results are indicative of a π back-bonding interaction, L(nπ*) ← RuII(dπ) for which L is the pyS, CNpy and Tio ligands. The half-wave formal potentials (E1/2) observed for the trans-[Ru(CNpy)(NH3)4(pyS)]2+, trans- [Ru(CNpy)(NH3)4(1,4-dt)]2+ and trans-[Ru(CNpy)(NH3)4(Tio)]2+ complexes: 1.00, 0.67 and 1.03 V vs NHE, respectively, are indicative of the stabilization of the metal in the reduced state comparatively to the start complex, trans-[Ru(CNpy)(NH3)4(OH2)]2+ (E1/2 = 0.35 V vs NHE). This result indicates, also, the strong π withdraw capability of the CNpy ligand. The shift observed for the νC≡N mode from 2239 cm-1 in the vibrational spectra of the CNpy free ligand to ∼2200 cm-1 upon coordination suggests that the coordination occurs through the nitrile fragment. For the pyS and Tio ligands, the observation of the signals assigned to the νC=S and νSH modes, respectively, in the vibrational spectra os the complexes indicates that the coordination occurs through the nitrogen atom os the pyridine ring. The SERS ex situ spectra of the gold surfaces modified with the isolated complexes allow the classification of these species as binfunctional molecules in which the sulfur atom of the pyS, 1,4-dt and Tio ligands is the adsorption site and the nitrogen atom of the CNpy pyridine ring is the functional terminal group. Also, the SERS results point for a trans conformation for the trans- [Ru(CNpy)(NH3)4(pyS)]2+ complex and for a gauche configuration for the trans- [Ru(CNpy)(NH3)4(1,4-dt)]2+ and trans-[Ru(CNpy)(NH3)4(Tio)]2+ complexes on gold. The intensity dependence of some signals in the SERS spectra with the applie potential reflects the π back-bonding effect on surface since this behavior is observed to be strongly related to the E1/2 values of the complexes. The reductive desorption potentials of the SAMs formed with the isolated compounds reflects the π withdraw capability of the CNpy ligand. This effect is much more intense for the trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+ complex since the π back-bonding interaction of the 1,4-dt ligand is lower than the CNpy, pyS and Tio ligands. The heterogeneous electron transfer reaction of the cytochrome c metalloprotein was satisfactorily assessed with the SAMs formed by the isolated complexes (E1/2 = 0.05 V vs Ag⏐AgCl⏐Cl-). The Best voltammetric response was observed with the SAM of the trans- [Ru(CNpy)(NH3)4(pyS)]2+ complex due to the trans conformation on surface.
Pinheiro, Solange de Oliveira. "Sintese , caracterização e eletroatividade de sams formadas com compostos catiônicos de tetraaminas de rutênio". reponame:Repositório Institucional da UFC, 2006. http://www.repositorio.ufc.br/handle/riufc/13712.
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Trans-[Ru(CNpy)(NH3)4(L)]2+ type complexes, where CNpy (4- Cyanopyridine), L= 1,4-dt (1,4-dithiane), pyS (4-mercaptopyridine), and Tio (thionicotinamide), were synthesized and characterized by HPLC, microanalysis, eletrochemistry and vibrational and eletronic spectroscopies. The eletrochemical and eletronic absorption results are indicative of a π back-bonding interaction, L(nπ*) ← RuII(dπ) for which L is the pyS, CNpy and Tio ligands. The half-wave formal potentials (E1/2) observed for the trans-[Ru(CNpy)(NH3)4(pyS)]2+, trans- [Ru(CNpy)(NH3)4(1,4-dt)]2+ and trans-[Ru(CNpy)(NH3)4(Tio)]2+ complexes: 1.00, 0.67 and 1.03 V vs NHE, respectively, are indicative of the stabilization of the metal in the reduced state comparatively to the start complex, trans-[Ru(CNpy)(NH3)4(OH2)]2+ (E1/2 = 0.35 V vs NHE). This result indicates, also, the strong π withdraw capability of the CNpy ligand. The shift observed for the νC≡N mode from 2239 cm-1 in the vibrational spectra of the CNpy free ligand to ∼2200 cm-1 upon coordination suggests that the coordination occurs through the nitrile fragment. For the pyS and Tio ligands, the observation of the signals assigned to the νC=S and νSH modes, respectively, in the vibrational spectra os the complexes indicates that the coordination occurs through the nitrogen atom os the pyridine ring. The SERS ex situ spectra of the gold surfaces modified with the isolated complexes allow the classification of these species as binfunctional molecules in which the sulfur atom of the pyS, 1,4-dt and Tio ligands is the adsorption site and the nitrogen atom of the CNpy pyridine ring is the functional terminal group. Also, the SERS results point for a trans conformation for the trans- [Ru(CNpy)(NH3)4(pyS)]2+ complex and for a gauche configuration for the trans- [Ru(CNpy)(NH3)4(1,4-dt)]2+ and trans-[Ru(CNpy)(NH3)4(Tio)]2+ complexes on gold. The intensity dependence of some signals in the SERS spectra with the applie potential reflects the π back-bonding effect on surface since this behavior is observed to be strongly related to the E1/2 values of the complexes. The reductive desorption potentials of the SAMs formed with the isolated compounds reflects the π withdraw capability of the CNpy ligand. This effect is much more intense for the trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+ complex since the π back-bonding interaction of the 1,4-dt ligand is lower than the CNpy, pyS and Tio ligands. The heterogeneous electron transfer reaction of the cytochrome c metalloprotein was satisfactorily assessed with the SAMs formed by the isolated complexes (E1/2 = 0.05 V vs Ag⏐AgCl⏐Cl-). The Best voltammetric response was observed with the SAM of the trans- [Ru(CNpy)(NH3)4(pyS)]2+ complex due to the trans conformation on surface.
Os complexos trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+ (CNpy = 4-Cianopiridina, 1,4- dt = 1,4-ditiano), trans-[Ru(CNpy)(NH3)4(pyS)]2+ (pyS = 4-mercaptopiridina) e trans- [Ru(CNpy)(NH3)4(Tio)]2+ (Tio = tionicotinamida) foram sintetizados e caracterizados por Cromatografia Líquida de Alta Eficiência, análise elementar, eletroquímica e espectroscopias eletrônica e vibracional. Os espectros de absorção eletrônica e os resultados de eletroquímica evidenciaram uma interação do tipo π back-bonding do centro metálico RuII para os ligantes piridínicos. Os valores dos potenciais formais de meia onda (E1/2) observados para os complexos trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+, trans-[Ru(CNpy)(NH3)4(pyS)]2+ e trans-[Ru(CNpy)(NH3)4(Tio)]2+: 1,00, 0,67 e 1,03 V vs ENH, respectivamente, indicam a estabilização do estado reduzido do centro metálico em relação ao complexo de partida trans-[Ru(CNpy)(NH3)4(OH2)]2+ (E1/2 = 0,35 V vs ENH). Esse resultado indica, também, a forte capacidade π retiradora do ligante CNpy que, no caso do complexo trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+, é tão intensa que facilita comparativamente o processo de oxidação do centro metálico. Podese concluir, portanto, que a capacidade π retiradora dos ligantes CNpy, pyS e Tio é similar. O deslocamento na freqüência de estiramento da ligação C≡N do ligante Cnpy livre de 2239 para ∼2200 cm-1 após coordenação ao centro metálico [Ru(NH3)4]2+ nos espectros vibracionais indica que a coordenação do ligante CNpy ocorre pelo grupamento nitrila. Para os ligantes pyS e Tio, a observação das bandas atribuídas aos νC=S e νSH, respectivamente, indica que a coordenação ocorre pelo átomo de nitrogênio do anel piridínico. Os espectros SERS ex situ das superfícies modificadas com os compostos isolados permitem a classificação destes como moléculas modificadoras bifuncionais, onde o átomo de enxofre dos ligantes pyS, 1,4-dt e Tio atuam como sítio de adsorção e o átomo de nitrogênio piridínico do ligante CNpy atua como grupo funcional terminal. Além disso, os resultados SERS sugerem uma conformação trans para o complexo trans-[Ru(CNpy)(NH3)4(pyS)]2+ e gauche para os complexos trans-[Ru(CNpy)(NH3)4(1,4-dt)]2+ e trans-[Ru(CNpy)(NH3)4(Tio)]2+ sobre ouro. A dependência nas intensidades das bandas com o potencial aplicado aos eletrodos modificados ilustra o efeito π back-bonding dos íons metálicos dos adsorbatos inorgânicos, uma vez que observa-se uma relação direta com os valores dos potenciais formais de meia onda dos complexos estudados. Os valores dos potenciais de dessorção redutiva observados para as SAMs dos complexos isolados refletem a capacidade π retiradora do ligante CNpy que se encontra na posição para em relação ao sítio de adsorção. Esse efeito é bem mais intenso no complexo trans- [Ru(CNpy)(NH3)4(1,4-dt)]2+, uma vez que a capacidade de interação π back-bonding do ligante 1,4-dt é significativamente menor que as dos ligantes pyS e Tio. Sugere-se, para esse complexo, uma oxidação parcial do centro metálico o que implica em uma intensificação da interação σ com o ligante 1,4-dt (RuII-S) e, conseqüentemente, um enfraquecimento da ligação Au-S. A reação hTE da metaloproteína cyt c foi observada em valor consistente com seu estado in natura indicando que as SAMs estudadas acessam satisfatoriamente o processo hTE do cyt c além de evitar a desnaturação desta proteína. A forma das curvas voltamétricas, entretanto, apresentou uma dependência com a configuração dos complexos sobre a superfície. Curvas de melhor definição foram obtidas com a SAM do complexo trans-[Ru(CNpy)(NH3)4(pyS)]2+ que apresenta uma configuração trans em relação à superfície.
Ben, Youssef Mariem. "Fonctionnalisation de surface des oxydes métalliques par des SAMs dipolaires; application aux cellules photovoltaïques". Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC157/document.
Pełny tekst źródłaThe insertion of very thin metal-oxide (MO) layers at the interface between the conductive electrodes (FTO/ITO, Metals) and the active layer (polymer, perovskite) presents a promising solution to improve the performances of organic and hybrid photovoltaic devices. The procedure is about introducing MO layers functionalized by dipolar self-assembling monolayer’s (SAMs) at the interface between the conductive electrode and the active layer. The SAM layers bearing dipoles perpendicular to the surface that can have a large impact on the electronic devices both by affecting the growth and organization of active organic layer and by tuning the work function of the MO layers. In this work we show that the grafting of dipole molecular on top of MO thin films can considerably affect the performance of the photovoltaic cell. The impact on these performances depends strongly on the orientation of the permanent dipole lying on the SAM molecule
Bennett, Megan. "Energy Transfer Dynamics in Collisions of Polar and Non-polar Gases with Functionalized Self-Assembled Monolayers". Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/33229.
Pełny tekst źródłaMaster of Science
Shuler, Shelby. "Investigation of Gas-Surface Dynamics Using an Ar Atomic Beam and Functionalized Self-Assembled Monolayers". Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/32686.
Pełny tekst źródłaMaster of Science
Meillan, Matthieu. "Immobilisation de biomolécules sur des monocouches auto-assemblées et élaboration de sondes AFM à nanotubes de carbonne fonctionnalisés pour des mesures d'interactions ligrand-récepteur". Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0109/document.
Pełny tekst źródłaDuring the development of biosensors, control of the surface on which the biomolecules areimmobilized is a crucial parameter for the reliability and reproducibility of the measurements. For thisPhD work, two main objectives were set:- obtain in a reproducible way functional organic films able to make inorganic surfacebiocompatible for the immobilization of biomolecules without any denaturation.- develop innovative tools in order to analyze the distribution of biomolecules on the surface etevaluate their biological activity at single molecule scaleThe immobilization step was done on SAMs terminated by a carboxylic acid function.In order to image surfaces, Atomic Force Microscopy (AFM) was chosen. This technique permits toobtain information at nanometric scale and to measure molecular interactions in the range ofpiconewton forces (10-12 N).MWCNTs were linked to a commercial AFM tip by micro-welding under optical microscopy. CNTswere biofunctionalized at the nanotube apex by an original dipping procedure.The interactions between a ligand, immobilized on the surface, and a receptor covalently linked to aCNT have been characterized
Bauer, Stella Valery [Verfasser], i Axel [Akademischer Betreuer] Rosenhahn. "Hydratation und Antifouling-Oberflächen: Modellsysteme auf Basis zwitterionischer SAMs und Polysaccharide / Stella Valery Bauer ; Betreuer: Axel Rosenhahn". Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180301420/34.
Pełny tekst źródłaJademan, Jessica, i Veronica Johansson. "”Vi sa bara förlåt och sedan blev vi sams" : En studie om konflikter och bemötande i förskolan". Thesis, Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-10314.
Pełny tekst źródłaMearns, Freya Justine Chemistry Faculty of Science UNSW. "A study of hybridisation of DNA immobilised on gold: strategies for DNA biosensing". Awarded by:University of New South Wales. Chemistry, 2006. http://handle.unsw.edu.au/1959.4/23978.
Pełny tekst źródłavon, Sydow Rebecca. "Social blandning och blandade upplåtelseformer : En kvantitativ studie med tonvikt på nyproducerade bostadsområden". Thesis, Stockholms universitet, Kulturgeografiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-90498.
Pełny tekst źródłaSPaDE
Mehring, Patrick Dennis [Verfasser], Carsten [Akademischer Betreuer] Westphal i Thomas [Gutachter] Weis. "SAMs organischer Halbleiter auf Au-Substraten : Eine STM-Untersuchung / Patrick Dennis Mehring. Betreuer: Carsten Westphal. Gutachter: Thomas Weis". Dortmund : Universitätsbibliothek Dortmund, 2013. http://d-nb.info/1103591363/34.
Pełny tekst źródłaMehring, Patrick [Verfasser], Carsten [Akademischer Betreuer] Westphal i Thomas [Gutachter] Weis. "SAMs organischer Halbleiter auf Au-Substraten : Eine STM-Untersuchung / Patrick Dennis Mehring. Betreuer: Carsten Westphal. Gutachter: Thomas Weis". Dortmund : Universitätsbibliothek Dortmund, 2013. http://d-nb.info/1103591363/34.
Pełny tekst źródłaPaulo, TÃrcio de Freitas. "SAMs de MolÃculas Sulfuradas: Estudo TermodinÃmico e CinÃtico de AdsorÃÃo e AplicaÃÃo em ReaÃÃes de TransferÃncia de ElÃtrons de Metaloproteinas". Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=6337.
Pełny tekst źródłaO emprego das tÃcnicas de eletroquÃmica, microbalanÃa de cristal quartzo (QCM â Quartz Crystal Microbalance) e ressonÃncia de plÃsmons de superfÃcie (SPR â Surface Plasmon Resonance) mostram que as espÃcies 1,4-ditiano (1,4-dt), 4-mercaptopiridina (pyS), 5-(4-piridil)-1,3,4-oxadiazol-2-tiol (Hpyt), tionicotinamida (TNA) e isotionicotinamida (iTNA) experimentam adsorÃÃo espontÃnea formando SAMs (Self-Assembled Monolayers) como resultado da imersÃo de substratos de ouro em soluÃÃo contendo estas espÃcies. As imagens obtidas por microscopia de varredura por tunelamento (STM â Scanning Tunneling Microscopy) indicam um arranjo prÃximo do hexagonal com exceÃÃo da iTNA cujas imagens nÃo foram conclusivas. Adicionalmente, as imagens indicam a existÃncia de defeitos nas SAMs mesmo apÃs longos perÃodos de imersÃo (24 h). Os estudos termodinÃmicos e cinÃticos dos processos de adsorÃÃo foram realizados por desorÃÃo redutiva em meio alcalino e QCM. Os valores dos potenciais de desorÃÃo redutiva, Edr, foram observados em −0,9, −0,8 e −0,5 V vs. Ag/AgCl/Cl- para a desorÃÃo de iTNA, TNA e Hpyt, respectivamente. Comparativamente Ãs espÃcies 1,4-dt (−0,8 V) e pyS (−0,5 V), o valor de Edr da SAM de Hpyt indica uma interaÃÃo sigma ao passo que aqueles observados para iTNA e TNA sugerem uma contribuiÃÃo pi adicional. Os valores de quantidade de material adsorvido (gama) e da taxa de recobrimento da superfÃcie (teta), calculados por desorÃÃo redutiva e impedÃncia eletroquÃmica, respectivamente, foram consistentes com as imagens de STM. Comparativamente aos resultados de desorÃÃo, os maiores valores de gama determinados por QCM foram atribuÃdos à presenÃa de molÃculas de Ãgua co-adsorvidas visto que foi observada uma relaÃÃo linear entre o excesso de massa e o momento de dipolo das espÃcies modificadoras. As curvas de desorÃÃo obtidas para pyS indicam a decomposiÃÃo da monocamada nÃo possibilitando, portanto, a determinaÃÃo dos parÃmetros termodinÃmicos e cinÃticos de adsorÃÃo. A correlaÃÃo com os resultados obtidos apÃs imersÃo do eletrodo de ouro em soluÃÃo de Na2S sugere que este processo està associado à quebra da ligaÃÃo C─S com formaÃÃo de uma camada de enxofre atÃmico e/ou oligomÃrico. As isotermas de adsorÃÃo obtidas para os processos de formaÃÃo das SAMs de Hpyt, TNA e iTNA, adequaram-se ao modelo de Langmuir permitindo a determinaÃÃo da variaÃÃo da energia livre de adsorÃÃo, ΔGads, como −35,9, −38,5 e −34,9 kJ mol−1, respectivamente. Estes valores sÃo indicativos de interaÃÃo forte sendo caracterÃsticos de processos de quimissorÃÃo. Para o modelo de Frumkin, os dados apresentaram melhores correlaÃÃes quando o parÃmetro de interaÃÃo (g) foi fixado em −0,45, −0,30 e −0,10, respectivamente, para as SAMs de Hpyt, TNA e iTNA indicando interaÃÃes repulsivas entre as molÃculas adjacentes. Os valores de pKa das SAMs de Hpyt (4,2), TNA (5,0 e 8,5) e iTNA (4,5 e 7,9) foi determinado por voltametria utilizando-se o Ãon complexo [Fe(CN)6]3−. Neste estudo, foram sugeridas modificaÃÃes, uma vez que o mÃtodo proposto na literatura dificulta a determinaÃÃo de mais de um valor de pKa como observado para as molÃculas de TNA e iTNA. As reaÃÃes de transferÃncia de elÃtrons (TE) das metaloproteÃnas citocromo c (cyt c) e mioglobina (Mb) foram estudadas utilizando-se as SAMs de Hpyt, TNA, iTNA, pyS e 1,4-dt. Para as SAMs de TNA e iTNA, o deslocamento positivo de 0,2V no valor do potencial de meia-onda do cyt c (pH~7,0) em relaÃÃo a forma nativa, foi atribuÃdo à densidade de carga positiva resultante da protonaÃÃo do grupo NH2 (pKa ~ 8,0). Resultados de QCM e SPR indicaram que hà a formaÃÃo de uma monocamada de cyt c sobre as SAMs estudadas. Esta monocamada, embora nÃo sendo redox ativa, permite o estudo da reaÃÃo de TE das molÃculas de cyt c em soluÃÃo sugerindo que este processo pode envolver os orbitais das molÃculas modificadoras. Para a metaloproteÃna Mb, utilizou-se uma SAM formada pelo aminoÃcido L-cisteÃna (cys), uma vez que nenhuma das SAMs estudadas acessou a reaÃÃo de TE. O processo redox foi observado em 0,086 V o que sugere a forma nativa. Os dados de QCM e SPR indicaram, tambÃm, a formaÃÃo de uma monocamada sobre a SAM de cys (Au/cys/Mb). Valores de â49,67 kJ mol−1 e −0,15 para ΔGads e g, respectivamente, foram calculados para a formaÃÃo da monocamada de Mb sobre a SAM de cys. O eletrodo Au/cys/Mb apresentou atividade catalÃtica em relaÃÃo a reaÃÃo de oxidaÃÃo do Ãcido ascÃrbico com uma diminuiÃÃo de 400 mV no sobrepotencial e uma reaÃÃo cineticamente controlada com uma constante de velocidade, kf, de ~2,0 x 10^4 L mol-1 s-1.
Electrochemical techniques, quartz crystal microbalance (QCM) and surface plÃsmons resonance (SPR) were used to study the formation of self-assembled monolayers (SAMs) of 1,4-ditiano (1,4-dt), 4-mercaptopyridine (pyS), 5-(4-piridinyl)-1,3,4-oxadiazole-2-thiol (Hpyt), thionicotinamide (TNA) and thioisonicotinamide (iTNA) as a result of the immersion of gold substrates into the respective solutions. STM (Scanning Tunneling Microscopy) images indicate the sulfur atom as the adsorption site of these molecules and a hexagonal conformation on surface. For the iTNA molecule, the images were not conclusive. In addition, the images indicated the existence of defects even after longer immersion times (24 h). Thermodynamic and kinetic aspects of the adsorption process were evaluated by reductive desorption in alkaline media and QCM. The reductive desorption potentials, Edr, were observed at −0.9, −0.8, and −0.5 V vs. Ag/AgCl for the desorption of iTNA, TNA and Hpyt, respectively. In comparison to 1,4-dt (−0.8 V) and pyS (−0.5 V) species, the Edr value of Hpyt indicates a sigma interaction whereas those of iTNA and TNA indicate an additional pi contribution. The values of the concentration of adsorbed material, gama, and fractional coverage (teta ~ 0.9), determined, respectively, by reductive desorption and impedance are consistent with the STM images. In comparison to the desorption data, the higher values of gama calculated by QCM were assigned to the presence of water molecules since a linear relation was observed between the dipole moment and the mass change calculated by QCM. The desorption curves acquired for the pyS SAM indicated the decomposition of the monolayer thus not allowing the determination of the thermodynamic and kinetic parameters of adsorption. In comparison with the results obtained for the electrode modified after immersion in Na2S solution, it was suggested that this process is associated to the cleavage of the C─S bond which results in the formation of an adlayer composed of atomic and/or oligomeric sulfur species. The adsorption isotherms for Hpyt, TNA and iTNA fitted the Langmuir model of adsorption allowing the determination of the free energy of adsorption, ΔGads, as −35.9, −38.5 and −34,9 kJ/mol, respectively. These values are indicative of strong interaction being typical of chemisorption. For the Frumkin model, the best correlation was found when the interaction parameter, g, was established as −0.45, −0.20 and −0.10 for Hpyt, TNA and iTNA, respectively, indicating repulsive interactions between the adjacent molecules. Cyclic voltammetry was used to determinate the pKa of the SAMs of Hpyt (4.2), TNA (5.0 and 8.5) and iTNA (4.5 and 7.9) by using [Fe(CN)6]3− as a probe molecule. For this study, some changes were suggested since in the method proposed in the literature the existence of more than one protonation site was not considered thus not allowing the determination of more than one pKa value as was observed for TNA and iTNA molecules. Electron transfer reactions (TE) of cytochrome c (cyt c) and myoglobin (Mb) metalloproteins were studied by using the SAMs of Hpyt, TNA, iTNA, pyS and 1,4-dt. For the SAMs formed with TNA and iTNA, the positive shift of 0.2V on the half-wave potential of cyt c in relation to that of the native protein, was assigned to the positive charge density on surface in consequence of the protonation of NH2 groups (pKa~8.0) since these measurements were carried out in physiological medium. QCM and SPR data indicated the formation of a monolayer of cyt c on the studied SAMs. This monolayer, although not being electroactive, allows the study of the TE reaction of the cyt c molecules in solution suggesting that this process involves the orbitals of the modifier molecules. For the Mb metalloprotein, a SAM of L-cysteine amino acid was used since none of the studied sulfur molecules was able to access the TE reaction. The redox process was observed at 0.086 V suggesting the native form of Mb. QCM and SPR data indicated, also, the formation of a monolayer of Mb on the cys SAM (Au/cys/Mb). Values of â49.67 kJ mol−1 and −0.15 for ΔGads and g, respectively, were calculated for the formation of the monolayer of Mb on the cys SAM. The electrode Au/cys/Mb presented catalytic activity toward the oxidation reaction of ascorbic acid presenting a decrease of 400 mV in the overpotential and a kinetic controlled with a rate constant, kf, of 2.0 x 104 L mol-1 s-1.
Cavadas, Francisco Troitino. "Spectroscopic and electrochemical investigation of phenyl, phenoxy, and hydroxyphenyl-terminated alkanethiol monolayers". Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/28611.
Pełny tekst źródłaPh. D.
Jakubowicz, Agnieszka. "Investigation of growth kinetics of self-assembling monolayers by means of contact angle, optical ellipsometry, angle-resolved XPS and IR spectroscopy". Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc4602/.
Pełny tekst źródłaBöhmler, Judith. "Well-controlled and well-described SAMs-based platforms for the study of material-bacteria interactions occuring at the molecular scale". Phd thesis, Université de Haute Alsace - Mulhouse, 2012. http://tel.archives-ouvertes.fr/tel-00847480.
Pełny tekst źródłaFast, Ellen [Verfasser], Thisbe K. [Akademischer Betreuer] Lindhorst i Ulrich [Gutachter] Lüning. "Synthese von Glycoazobenzol-Konjugaten zur Verbesserung der Photoschaltbarkeit von Glyco-SAMs / Ellen Fast ; Gutachter: Ulrich Lüning ; Betreuer: Thisbe K. Lindhorst". Kiel : Universitätsbibliothek Kiel, 2020. http://d-nb.info/1203624603/34.
Pełny tekst źródłaPaulo, Tércio de Freitas. "SAMs de Moléculas Sulfuradas: Estudo Termodinâmico e Cinético de Adsorção e Aplicação em Reações de Transferência de Elétrons de Metaloproteinas". reponame:Repositório Institucional da UFC, 2011. http://www.repositorio.ufc.br/handle/riufc/10364.
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Electrochemical techniques, quartz crystal microbalance (QCM) and surface plásmons resonance (SPR) were used to study the formation of self-assembled monolayers (SAMs) of 1,4-ditiano (1,4-dt), 4-mercaptopyridine (pyS), 5-(4-piridinyl)-1,3,4-oxadiazole-2-thiol (Hpyt), thionicotinamide (TNA) and thioisonicotinamide (iTNA) as a result of the immersion of gold substrates into the respective solutions. STM (Scanning Tunneling Microscopy) images indicate the sulfur atom as the adsorption site of these molecules and a hexagonal conformation on surface. For the iTNA molecule, the images were not conclusive. In addition, the images indicated the existence of defects even after longer immersion times (24 h). Thermodynamic and kinetic aspects of the adsorption process were evaluated by reductive desorption in alkaline media and QCM. The reductive desorption potentials, Edr, were observed at −0.9, −0.8, and −0.5 V vs. Ag/AgCl for the desorption of iTNA, TNA and Hpyt, respectively. In comparison to 1,4-dt (−0.8 V) and pyS (−0.5 V) species, the Edr value of Hpyt indicates a sigma interaction whereas those of iTNA and TNA indicate an additional pi contribution. The values of the concentration of adsorbed material, gama, and fractional coverage (teta ~ 0.9), determined, respectively, by reductive desorption and impedance are consistent with the STM images. In comparison to the desorption data, the higher values of gama calculated by QCM were assigned to the presence of water molecules since a linear relation was observed between the dipole moment and the mass change calculated by QCM. The desorption curves acquired for the pyS SAM indicated the decomposition of the monolayer thus not allowing the determination of the thermodynamic and kinetic parameters of adsorption. In comparison with the results obtained for the electrode modified after immersion in Na2S solution, it was suggested that this process is associated to the cleavage of the C─S bond which results in the formation of an adlayer composed of atomic and/or oligomeric sulfur species. The adsorption isotherms for Hpyt, TNA and iTNA fitted the Langmuir model of adsorption allowing the determination of the free energy of adsorption, ΔGads, as −35.9, −38.5 and −34,9 kJ/mol, respectively. These values are indicative of strong interaction being typical of chemisorption. For the Frumkin model, the best correlation was found when the interaction parameter, g, was established as −0.45, −0.20 and −0.10 for Hpyt, TNA and iTNA, respectively, indicating repulsive interactions between the adjacent molecules. Cyclic voltammetry was used to determinate the pKa of the SAMs of Hpyt (4.2), TNA (5.0 and 8.5) and iTNA (4.5 and 7.9) by using [Fe(CN)6]3− as a probe molecule. For this study, some changes were suggested since in the method proposed in the literature the existence of more than one protonation site was not considered thus not allowing the determination of more than one pKa value as was observed for TNA and iTNA molecules. Electron transfer reactions (TE) of cytochrome c (cyt c) and myoglobin (Mb) metalloproteins were studied by using the SAMs of Hpyt, TNA, iTNA, pyS and 1,4-dt. For the SAMs formed with TNA and iTNA, the positive shift of 0.2V on the half-wave potential of cyt c in relation to that of the native protein, was assigned to the positive charge density on surface in consequence of the protonation of NH2 groups (pKa~8.0) since these measurements were carried out in physiological medium. QCM and SPR data indicated the formation of a monolayer of cyt c on the studied SAMs. This monolayer, although not being electroactive, allows the study of the TE reaction of the cyt c molecules in solution suggesting that this process involves the orbitals of the modifier molecules. For the Mb metalloprotein, a SAM of L-cysteine amino acid was used since none of the studied sulfur molecules was able to access the TE reaction. The redox process was observed at 0.086 V suggesting the native form of Mb. QCM and SPR data indicated, also, the formation of a monolayer of Mb on the cys SAM (Au/cys/Mb). Values of –49.67 kJ mol−1 and −0.15 for ΔGads and g, respectively, were calculated for the formation of the monolayer of Mb on the cys SAM. The electrode Au/cys/Mb presented catalytic activity toward the oxidation reaction of ascorbic acid presenting a decrease of 400 mV in the overpotential and a kinetic controlled with a rate constant, kf, of 2.0 x 104 L mol-1 s-1.
O emprego das técnicas de eletroquímica, microbalança de cristal quartzo (QCM – Quartz Crystal Microbalance) e ressonância de plásmons de superfície (SPR – Surface Plasmon Resonance) mostram que as espécies 1,4-ditiano (1,4-dt), 4-mercaptopiridina (pyS), 5-(4-piridil)-1,3,4-oxadiazol-2-tiol (Hpyt), tionicotinamida (TNA) e isotionicotinamida (iTNA) experimentam adsorção espontânea formando SAMs (Self-Assembled Monolayers) como resultado da imersão de substratos de ouro em solução contendo estas espécies. As imagens obtidas por microscopia de varredura por tunelamento (STM – Scanning Tunneling Microscopy) indicam um arranjo próximo do hexagonal com exceção da iTNA cujas imagens não foram conclusivas. Adicionalmente, as imagens indicam a existência de defeitos nas SAMs mesmo após longos períodos de imersão (24 h). Os estudos termodinâmicos e cinéticos dos processos de adsorção foram realizados por desorção redutiva em meio alcalino e QCM. Os valores dos potenciais de desorção redutiva, Edr, foram observados em −0,9, −0,8 e −0,5 V vs. Ag/AgCl/Cl- para a desorção de iTNA, TNA e Hpyt, respectivamente. Comparativamente às espécies 1,4-dt (−0,8 V) e pyS (−0,5 V), o valor de Edr da SAM de Hpyt indica uma interação sigma ao passo que aqueles observados para iTNA e TNA sugerem uma contribuição pi adicional. Os valores de quantidade de material adsorvido (gama) e da taxa de recobrimento da superfície (teta), calculados por desorção redutiva e impedância eletroquímica, respectivamente, foram consistentes com as imagens de STM. Comparativamente aos resultados de desorção, os maiores valores de gama determinados por QCM foram atribuídos à presença de moléculas de água co-adsorvidas visto que foi observada uma relação linear entre o excesso de massa e o momento de dipolo das espécies modificadoras. As curvas de desorção obtidas para pyS indicam a decomposição da monocamada não possibilitando, portanto, a determinação dos parâmetros termodinâmicos e cinéticos de adsorção. A correlação com os resultados obtidos após imersão do eletrodo de ouro em solução de Na2S sugere que este processo está associado à quebra da ligação C─S com formação de uma camada de enxofre atômico e/ou oligomérico. As isotermas de adsorção obtidas para os processos de formação das SAMs de Hpyt, TNA e iTNA, adequaram-se ao modelo de Langmuir permitindo a determinação da variação da energia livre de adsorção, ΔGads, como −35,9, −38,5 e −34,9 kJ mol−1, respectivamente. Estes valores são indicativos de interação forte sendo característicos de processos de quimissorção. Para o modelo de Frumkin, os dados apresentaram melhores correlações quando o parâmetro de interação (g) foi fixado em −0,45, −0,30 e −0,10, respectivamente, para as SAMs de Hpyt, TNA e iTNA indicando interações repulsivas entre as moléculas adjacentes. Os valores de pKa das SAMs de Hpyt (4,2), TNA (5,0 e 8,5) e iTNA (4,5 e 7,9) foi determinado por voltametria utilizando-se o íon complexo [Fe(CN)6]3−. Neste estudo, foram sugeridas modificações, uma vez que o método proposto na literatura dificulta a determinação de mais de um valor de pKa como observado para as moléculas de TNA e iTNA. As reações de transferência de elétrons (TE) das metaloproteínas citocromo c (cyt c) e mioglobina (Mb) foram estudadas utilizando-se as SAMs de Hpyt, TNA, iTNA, pyS e 1,4-dt. Para as SAMs de TNA e iTNA, o deslocamento positivo de 0,2V no valor do potencial de meia-onda do cyt c (pH~7,0) em relação a forma nativa, foi atribuído à densidade de carga positiva resultante da protonação do grupo NH2 (pKa ~ 8,0). Resultados de QCM e SPR indicaram que há a formação de uma monocamada de cyt c sobre as SAMs estudadas. Esta monocamada, embora não sendo redox ativa, permite o estudo da reação de TE das moléculas de cyt c em solução sugerindo que este processo pode envolver os orbitais das moléculas modificadoras. Para a metaloproteína Mb, utilizou-se uma SAM formada pelo aminoácido L-cisteína (cys), uma vez que nenhuma das SAMs estudadas acessou a reação de TE. O processo redox foi observado em 0,086 V o que sugere a forma nativa. Os dados de QCM e SPR indicaram, também, a formação de uma monocamada sobre a SAM de cys (Au/cys/Mb). Valores de –49,67 kJ mol−1 e −0,15 para ΔGads e g, respectivamente, foram calculados para a formação da monocamada de Mb sobre a SAM de cys. O eletrodo Au/cys/Mb apresentou atividade catalítica em relação a reação de oxidação do ácido ascórbico com uma diminuição de 400 mV no sobrepotencial e uma reação cineticamente controlada com uma constante de velocidade, kf, de ~2,0 x 10^4 L mol-1 s-1.
Adamkiewicz, Malgorzata. "Self-assembled monolayers on silicon : deposition and surface chemistry". Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3938.
Pełny tekst źródłaWiley, Devon S. "Oxide Nanofilms from Nanoparticle Suspensions Deposited on Functionalized Surfaces". Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1217022473.
Pełny tekst źródłaMousli, Yannick. "Synthès de nano-films bio-fonctionnels pour l'immobilisation spécifique d'espèces biologiques". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0840/document.
Pełny tekst źródłaControl of surface physicochemical properties is a key aspect for the development of many biotechnological tools, such as biosensors. For analysis and diagnostic, the functionalization of silica-based surfaces may be carried out through the creation of an organic nano-film named a Self-Assembled Monolayer (SAM). The main goal of this PhD work is thus to synthesize monolayer on SiO2 substrates in order give them biofunctionality, aiming at developing a versatile biodetection platform.In order to do so, we focused on the synthesis of two types of coupling agents, either bearing an azide moiety or a biotin. This organic synthesis work led to two new sorts of functional organosilanes which can be directly grafted onto silica surfaces. Biofunctionality itself is introduced by the biotin, either through the formation of the monolayer or through click chemistry on azide-functionalized SAMs.Said surfaces were then fully characterized using Polarization Modulation Infrared Reflection-Absorption Spectroscopy (PM-IRRAS) an Atomic Force Microscopy (AFM). Bioactivity of biotinylated surfaces was then monitored using streptavidin conjugated with HRP in order to catalyze the redox reaction of chromogenic substrates
Killian, Manuela S. [Verfasser], i Patrik [Akademischer Betreuer] Schmuki. "Organic Modification of TiO2 and other Metal Oxides with SAMs and Proteins - a Surface Analytical Investigation / Manuela S. Killian. Gutachter: Patrik Schmuki". Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2013. http://d-nb.info/1065378084/34.
Pełny tekst źródłaRechmann, Julian [Verfasser], Andreas Gutachter] Erbe i Axel [Gutachter] [Rosenhahn. "Modification of metal surface electronic properties by phenothiazine-based SAMs / Julian Rechmann ; Gutachter: Andreas Erbe, Axel Rosenhahn ; Fakultät für Chemie und Biochemie". Bochum : Ruhr-Universität Bochum, 2020. http://nbn-resolving.de/urn:nbn:de:hbz:294-69146.
Pełny tekst źródłaRechmann, Julian [Verfasser], Andreas [Gutachter] Erbe i Axel [Gutachter] Rosenhahn. "Modification of metal surface electronic properties by phenothiazine-based SAMs / Julian Rechmann ; Gutachter: Andreas Erbe, Axel Rosenhahn ; Fakultät für Chemie und Biochemie". Bochum : Ruhr-Universität Bochum, 2020. http://d-nb.info/1204258538/34.
Pełny tekst źródłaRouviere, Lisa. "Synthèse organique de silanes fonctionnels et élaboration de monocouches fluorogènes bioconjugables". Thesis, Bordeaux, 2021. http://www.theses.fr/2021BORD0027.
Pełny tekst źródłaAs part of the development of biosensors, fluorogenic self-assembled monolayers (SAMs) that can immobilize a bioreceptor in a bio-orthogonal way revealing the covalent bond between the bioreceptor and the monolayer were elaborated. The Huisgen 1,3- dipolar reaction between an azide and an alkyne was chosen as the bio-orthogonal reaction. The covalent immobilization of the bioreceptor will be visualize by a modulation of the fluorescence. To do this, two families of molecules, coumarines and naphthalimides, have been studied. The introduction of an azide or an alkyne in a specific position quench the fluorescence of the chromophores. The fluorescence will be released after the immobilization of the bioreceptor. New fluorogenic functional monolayers have been characterized by Polarization Modulation-Infrared Reflection-Adsorption Spectroscopy (PM-IRRAS) to confirm the grafting of the organosilanes and by fluorescence to monitor the click reaction
Liličenko, Nadežda [Verfasser]. "Adsorption kinetic investigations of phthalocyanine derivatives self assembled monolayers (SAMs) on gold: Temperature influence on the SAM formation process and quality / Nadežda Liličenko". Kassel : Universitätsbibliothek Kassel, 2015. http://d-nb.info/1075466954/34.
Pełny tekst źródłaAydogmus, Turkan. "Thermodynamic and transport properties of self-assembled monolayers from molecular simulations". Texas A&M University, 2004. http://hdl.handle.net/1969.1/3080.
Pełny tekst źródłaSiurdyban, Elise. "Immobilisation de dérivés du cryptophane-A sur des surfaces planes SiO2/or et or ainsi que sur des nanoparticules magnétiques". Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0149/document.
Pełny tekst źródłaCryptophanes are spherical molecules that can encapsulate neutral molecules(halogenomethanes, xenon), and ionic species like cesium and thallium cations in their lipophiliccavity. Our objective was to covalently immobilize these molecular cages onto solid substrates tocreate a material able to extract toxic cations such as thallium in aqueous media. Different strategieswere considered to optimize the immobilization of cryptophane-A derivatives onto silica and goldsurfaces (flat surfaces and core-shell magnetic nanoparticles). Mono-acid cryptophane-A (1) andhexa-acid cryptophane-A (2) were immobilized onto silica surfaces that were functionalized by aminogroups beforehand. Alcanethiols cryptophane-A (3), 1 and 2 modified by cysteamine (cryptophanes 4and 5 ,respectively) were immobilized onto gold surfaces. Flat surfaces were characterized bypolarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS) to estimate thesurface coverage of different cryptophane monolayers and to evaluate the most effective method. Asurface coverage close to 100% was obtained for the cryptophane 3 immobilized onto gold surfaces.This compound has been also immobilized efficiently onto magnetic nanoparticles (γ-Fe2O3/SiO2)coated with gold nano-shell. These results allow to consider the synthesis of cryptophane bearing fivehydroxyl and one thiol functions to create materials able to extract toxic cations
Cunning, Benjamin V. "An Exploration in Nano-Carbons: Bulk Graphene, Ultrafast Physics, Carbon-Nanotubes". Thesis, Griffith University, 2013. http://hdl.handle.net/10072/367408.
Pełny tekst źródłaThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Physical Sciences
Science, Environment, Engineering and Technology
Full Text
Ramin, Michael. "Synthèses de nouvelles monocouches auto-assemblées à partir d’organosilanes fonctionnels capables d’auto-association par liaisons hydrogène". Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14181/document.
Pełny tekst źródłaThere is an increasing demand for biosensors to detect pathogens in environmental and medical fields. In this context, the control of the surface properties plays an important role. Self-Assembled Monolayers (SAMs) allow to functionalize these surfaces homogeneously and reproducible. SAMs on silicon based surfaces are usually obtained from silylated coupling agents with long alkyl chain. However, these compounds are often difficult to purify owing to their low solubility in organic solvents. That’s why we proposed to introduce a polar function (amide or urea) in the molecular structure. These precursors were also capable of association by H-bonds and offer possibilities to control the organic assembly on the surfaces. The new functional monolayers were characterized by Polarization Modulation Infrared Reflection Adsorption Spectroscopy (PM-IRRAS) and others techniques such as XPS and contact angle in order to identify the different molecular groups on the surface. These functionalized monolayers have also shown their ability to immobilize biomolecules (Protein A)
Crivillers, Clusella Núria. "Organitzacions bi i tridimensionals de molècules electroactives per aplicacions en dispositius". Doctoral thesis, Universitat Autònoma de Barcelona, 2008. http://hdl.handle.net/10803/3280.
Pełny tekst źródłaEn aquesta Tesi s'han estudiat les organitzacions de dues famílies d'espècies electroactives, els tetratiafulvalens (TTFs) i els radicals policlorotrifenilmetílics (PTMs), que s'han utilitzat per la preparació de transistors orgànics d'efecte de camp (OFETs) i interruptors moleculars, respectivament.
Els OFETs estan inclosos dintre del que es coneix com l'electrònica dels plàstics. Alguns derivats de TTFs posseeixen unes característiques electròniques i estructurals apropiades per ser utilitzats com a semiconductors orgànics per OFETs. En aquesta Tesi es descriuen els principals resultats obtinguts en la síntesi i estudi de les propietats elèctriques com a OFETs dels derivats de TTF ditiofetetratiafulvalè (DT-TTF) i el dibenzotetratiafulvalè (DB-TTF). OFETs basats en cristalls que han estat processats a partir de solució, han donat mobilitats molt altes d'1 i 3.65 cm2/Vs, pel DB-TTF i el DT-TTF, respectivament. S'han preparat pel·lícules altament ordenades del DT-TTF utilitzant la tècnica de Zone Casting, i s'han obtingut mobilitats de l'ordre del silici amorf i, per tant, amplien la possibilitat d'utilizar-los en l'electrònica de baix cost.
Ja que la miniaturització dels dispositius és un dels principals objectius de l'electrònica molecular, la possibilitat de fabricar-los amb un nombre reduït de molècules és una aproximació molt atractiva. Amb aquesta finalitat, s'han preparat monocapes auto-assemblades (SAMs) basades en radicals PTM. Aquestes compostos són espècies multifuncionals ja que combinen propietats òptiques, magnètiques i electroquímiques. Les SAMs s'han preparat sobre substrats derivats del SiO2 i Au. S'ha demostrat el comportament com a interruptor molecular (químic i electroquímic) dels substrats funcionalitzats amb radicals PTM i s'ha utilitzat la resposta òptica o magnètica per llegir l'estat de l'interruptor.
D'altra banda, també s'ha estudiat per microscòpia de força atòmica (AFM) i microscòpia d'efecte túnel (STM) el tipus d'organització que formen alguns derivats de TTF i PTM fisisorbits sobre substrats de diferent naturalesa (grafit, mica i SiO2). L'auto-assemblatge sobre grafit d'un derivat de radical PTM funcionalitzat amb tres cadenes alquíliques llargues ha donat lloc a la formació d'estructures tipus fibril·lars altament ordenades, formades per files magnètiques separades per les cadenes alquíliques, que actuen com a barreres diamagnètiques. En el cas dels TTFs, s'ha estudiat l'organització bi i tridimensional del tricarbometoxitetratiafulvalè (TCM-TTF). S'ha observat que les interaccions molècula-molècula, molècula-substrat i molècula-dissolvent tenen un paper molt important en l'organització resultant, formant-se des de capes fins a fibres moleculars.
The construction of molecular devices with specific applications has attracted a great deal of attention in recent years since they can offer new advantages to well-established silicon-based technologies. Often, to construct a molecular device it is necessary to deposit molecules or material on a suitable substrate. Since the ordering and packing of the molecules are crucial aspects for the operation of the device, it is important to have good control of how solvent, substrate or molecular funcionalitzation influences on the resulting molecular assemblies and the intermolecular interactions.
In this Thesis we have studied the organizations of two families of electroactive molecules, tetrathiafulvalenes (TTFs) and polychlorotriphenylmethyl (PTM) radicals, which have been used as the active components of Organic Field Effect Transistors (OFETs) and molecular switches, respectively.
OFETs are included in the field of Plastic Electronics. Some TTF derivatives have appropriate structural and electronic characteristics to be used as organic semiconductors in OFETs. The main results related to the synthesis and the electrical properties as OFETs of the dithiophene-tetrathiafulvalene (DT-TTF) and dibenzo-tetrathiafulvalene (DB-TTF) are described in this Thesis. OFETs based on single crystals obtained from solution of these synthesized compounds have resulted in mobilities of 1 cm2/Vs and 3.6 cm2/Vs, for DB-TTF and DT-TTF, respectively, being the later the highest mobility reported for solution-processed devices. Highly ordered films based on DT-TTF were prepared by Zone Casting exhibiting also high mobilities, of the order of 0.2 cm2/Vs. Thus, this technique offers a promising approach to obtain low-cost devices with large area coverage.
Since the miniaturization of the devices is one of the main aim in the field of molecular electronics, the possibility to fabricate a device with a small group of molecules is a very attractive approach. With this purpose, self-assembled monolayers (SAMs) based on PTM radicals have been prepared. These are multifunctional species that combine optical, magnetic and electrochemical properties. SAMs of PTM radicals have been formed on silicon dioxide-based substrates and gold. It has been demonstrated that the resulting functionalized substrates can be used as molecular switches (chemical and electrochemical), using the optical and magnetic response to read the status of the switch.
We have also studied by AFM and STM the self-assembly of some TTFs and PTMs derivatives physisorbed on surface. A new PTM radical bearing long alkyl chains was synthesized and its self-assembly on graphite was studied by STM at the liquid-solid interface. The self-assembly of this PTM radical gave highly-ordered structures composed by magnetic double rows, formed by the PTM cores, separated by the alkyl chains that act as insulating diamagnetic barriers and determine the spacing between the rows. On the other hand, we have studied the organization of the tetra(carbometoxy)-tetrathiafulvalene (TCM-TTF) and it was observed that depending on the combination of the two main parameters (solvent and substrate) the resulting two-dimensional assemblies can be completely different, ranging from molecular layers to long molecular fibers.
Kleinert, Mike [Verfasser]. "Cluster-Glycoside als Bausteine für selbstanordnende Monoschichten (SAMs) : Glyco-SAMs als Glycocalix-Mimetika / vorgelegt von Mike Kleinert". 2005. http://d-nb.info/977247546/34.
Pełny tekst źródłaLin, Tzung-Han, i 林宗翰. "Silicon nanoelectronic sensors with SAMs selective surface passivation". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/01757342341900179060.
Pełny tekst źródła國立交通大學
材料科學與工程學系奈米科技碩博士班
101
In this study, selective ablation of self-assembly monolayer methoxy-poly (ethylene glycol) silane (MPEG-sil) and Octadecyltrichlorosilane (OTS) on silicon nanoelectronic devices by localize joule heating was demonstrated for biosensing application. Lightly doped region in a silicon nanoelectronic device is usually functioned as the active channel which is sensitive to the change of surface potential. And, the resistance of this region is higher compared to other regions in a device so that the electric power consumed. SAMs on lightly doped region were ablated during Joule heating leaving the rest area passivated. The subthreshold swing of nanoelectronic device almost kept unchanged after Joule heating. AFM was adopted to characterize the device surface before and after Joule heating and selective biomolecule modifications. Analysis of fluorescent results showed consistency with AFM results that selectivity in surface modofications was achieved. We found that SAM-ablated device possess potential in the increase of sensing response and in the increase of sensitivity for low concentration detection. In streptavidin detection, the device with selective modification exhibited a detection limits of 15 pM, while the device without selective modification showed an order of magnitude higer in its limit of detection.
Chang, Yi-Cheng, i 張義正. "Studies of Nanoscale Organic Molecules SAMs on ITO-Glass". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/94292554066847065539.
Pełny tekst źródła淡江大學
化學學系碩士班
98
Some nanoscale organic molecules were designed based on the combination of thiophenyl and phenyl structures. A series of designed compounds was successfully synthesized and theirs (SAM) formations on ITO-glass also were achieved. The conductance of these SAMs were measured by conductive Atomic Force Microscopy (c-AFM) technology. The experimental results showed that the conductivity values were determined by the contact surface structure of its SAM.
TSAI, MENG-TING, i 蔡孟廷. "Study of Work Function Modulation with Self-Assembled Monolayers(SAMs)". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/f3s48e.
Pełny tekst źródła國立中正大學
化學暨生物化學研究所
105
The purpose of this research is to find a self-assembled monolayer system to modify gold surface and maximize the change in its work function, so as to facilitate charge injection in organic electronic devices when using the metal as electrode. The change of work function relates to the dipole moment of the molecule used to modify the electrode surface along the surface normal. However, the CF3SO2BnCH2SH (dipole : 6.52 debye) -modified Au has lower work function(work function : 5.33 eV) than CF3BnCH2SH(dipole : 3.99 debye) -modified Au (work function : 5.81 eV). It is presumed that with higher dipole of molecule, there is stronger electrostatic repulsion between molecules so that either a closely-packed monolayer cannot be formed or the direction of the dipole is pushed away from the normal of the surface. To reduce the repulsion, two methods are proposed. One is to use mixed monolayer containing molecules with the same terminal functional group but with different molecular length. The other is to improve the intermolecular attractions in a mixed layer with electron-poor and electron-rich arenes. In specific mixing ratios, both methods can achieve a work function higher than what a single component monolayer can achieve. It is worth noting that in the former one, the adsorption density of mixed monolayer is ~10% more than single component monolayer by cyclic voltammetry and X-ray photon spectrum.
Lee, Tzu-Nien, i 李子念. "The Study of SAMs/SiO2 Stacked Sensing Membrane for ISFETs". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/45925080917437867195.
Pełny tekst źródła國立暨南國際大學
電機工程學系
101
In this thesis, the SAM/SiO2 stacked sensing membrane was used to improve the sensing characteristic of ISFETs. In our results, the sensitivity, hysteresis and drift of EIS with the SAM/SiO2 stacked sensing membrane were all improved. Besides, the sensitivity of ISFETs was also improved .This technology will be suitable for the future high sensitivity ISFETs.