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Корчака, Микола Олександрович. "Інтегральні сенсори струму на ефекті Холла з магнітною компенсацією напруження". Master's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/40371.
Повний текст джерелаThe thesis consists of an introduction, five sections, conclusions, a list of sources used. The total volume of the thesis is 94 pages, including 85 pages of the main text, 65 figures, 25 tables, a list of used sources from 56 titles. The purpose of the thesis is to develop a semiconductor integrated current sensor on the Hall effect with a voltage compensation circuit that uses an integrated inductor. The theory of electric circuits, the theory of self-regulation and control is used in solving the tasks set in the work for the development and design of an integrated current sensor on the Hall effect. Mathematical calculations were performed in the MATLAB software environment. Simulations of electric circuits were performed in the Cadence Virtuoso software environment. During the simulations, Monte Carlo methods were used to statistically consider random processes in the manufacture of semiconductor integrated circuits. As a result of work the integrated current sensor on Hall effect with the scheme of stress compensation which allows to provide invariability of sensitivity of a Hall element within no more than 1% during long operation of the device was designed. The novelty of the work is that the compensation scheme is implemented entirely in the analog domain and does not require additional calculations in the digital part of the sensor. The results can be used not only for Hall effect current sensors, but also for other integrated circuits that use Hall elements, such as tracking objects position, measuring the speed and direction of rotation of the motor, for contactless switching. For further research it is necessary to make a prototype of the designed sensor on silicon and to continue the analysis of its characteristics.
Аршан, Євгеній Віталійович. "Система адаптивного керування освітленням". Master's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/40353.
Повний текст джерелаWhen reviewing the technical literature, a study of existing lighting controls systems, their advantages and disadvantages. Two methods of lighting control were also investigated: employment sensing and light sensing, which are then used to develop the system. According to the results of the analysis of the technical task and review of scientific and technical literature, the relevance of creating a lighting control system was confirmed, which will automate the lighting of premises and will be a profitable solution in terms of energy-saving. As a result of the review, it was decided to use two types of sensors in the system in parallel: light sensors and motion sensors. Variant lighting control options have been developed using wired and wireless communication between components and a decision has been made to use a mixed type of communication. The structural scheme of the adaptive lighting control system, the algorithm of this system operation is developed and the code for software connection of system components is written. It is possible to further refine this system for outdoor lighting control and in more complex adaptive control algorithms, taking into account data from sensors of biotelemetric quantities that take into account user characteristics.
Пивоваренко, В. Г. "О-гликозиды 3-арил-, 3-арилокси- и 3-гетарилхромонов". Дис. канд. хім. наук, КГУ им. Т.Г. Шевченко, 1986.
Знайти повний текст джерелаCullion, Paul D. "3-Regularizing 3-semiFayers Partitions." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1335230915.
Повний текст джерелаROBINET, SOPHIE. "Fluorescence d'ions ln#3#+ (eu#3#+, dy#3#+, tb#3#+, ce#3#+) dans des solutions solides fluorees desordonnees de type fluorine." Clermont-Ferrand 2, 1993. http://www.theses.fr/1993CLF21579.
Повний текст джерелаMORTIER, MICHEL. "Luminescence des ions ni#2#+ et cr#3#+ dans balif#3, kmgf#3 et rbcaf#3." Paris 6, 1994. http://www.theses.fr/1994PA066656.
Повний текст джерелаCRUZ, SIMONE F. de A. "Crescimento e caracterizacao de monocristais de BaYsub(2)Fsub(8):TR onde TR=Ndsup(3+), Prsup(3+), Ersup(3+), Tbsup(3+), Dy sup(3+)." reponame:Repositório Institucional do IPEN, 2008. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11732.
Повний текст джерелаMade available in DSpace on 2014-10-09T14:05:56Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Center, University of Arizona Water Resources Research. "Arroyo Vol. 3 No. 3 (December 1989)." Water Resources Research Center, College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/314788.
Повний текст джерелаBikanga, Raphaël. "Proprietes tensioactives de derives 3-0-acyle, 3-0-alkyle et 3-desoxy-3-s-alkyle du d-glucose." Amiens, 1993. http://www.theses.fr/1993AMIES003.
Повний текст джерелаOrvesten, Maria. "Händelser vid Rickleån : 3 möten i 3 skalor." Thesis, KTH, Arkitektur, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-97939.
Повний текст джерелаLisa, Charlotte Pattenden. "Investigation ofa Metal Catalysed [3+3] Annelation Reaction." Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.489732.
Повний текст джерелаManak, Michael S. "Molecular analysis of 14-3-3 protein interactions." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013769.
Повний текст джерелаPereyra, Ravinez Orlando Luís [UNESP]. "Violação de CP em modelos 3-3-1." Universidade Estadual Paulista (UNESP), 1998. http://hdl.handle.net/11449/132835.
Повний текст джерелаPereyra, Ravinez Orlando Luís. "Violação de CP em modelos 3-3-1 /." São Paulo : [s.n.], 1998. http://hdl.handle.net/11449/132835.
Повний текст джерелаClokie, Samuel J. H. "Protein kinases that phosphorylate 14-3-3 isoforms." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/30559.
Повний текст джерелаPerry, Andrew John. "Fabrication and modelling of 3-3 piezoelectric composites." Thesis, University of Bath, 2002. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268749.
Повний текст джерелаEdwards, David Ryan. "Towards liquid crystalline [3 + 3] Schiff-base macrocycles." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31612.
Повний текст джерелаScience, Faculty of
Chemistry, Department of
Graduate
Marks, Lori J. "IntelliTalk 3." Digital Commons @ East Tennessee State University, 2005. https://dc.etsu.edu/etsu-works/3688.
Повний текст джерелаMarks, Lori J. "IntelliMathics 3." Digital Commons @ East Tennessee State University, 2005. https://dc.etsu.edu/etsu-works/3687.
Повний текст джерелаFernández, García Daniela, and Flores Alejandro Caamaño. "Sol 3." Tesis, Universidad de Chile, 2017. http://repositorio.uchile.cl/handle/2250/144413.
Повний текст джерелаDaniela Fernández García [Parte I], Alejandro Caamaño Flores [Parte II ]
Sol 3 maximiza el potencial de nuevas tecnologías de información satelital, presentando un negocio altamente innovador. En un entorno de cambio climático, la accesibilidad y gestión de información climática se vuelve un factor de interés para muchos sectores, dadas sus implicancias sociales, estratégicas y operacionales. Sol 3 es una consultora IT especializada que surge frente a las oportunidades que ofrecen estos nuevos desafíos, ofreciendo soluciones en gestión climática, con una visión clara: transformar la información climática, haciéndola más precisa, más apta y oportuna. Durante los primeros cinco años, el mercado objetivo será el rubro agrícola, dado su atractivo como mercado de entrada. No obstante, la versatilidad de los datos climáticos permite la generación de un negocio con potencial de expansión hacia diferentes rubros. Para ello, se requieren estudios específicos, por lo que el análisis se limitará a ese periodo. Específicamente, Sol 3 ofrece soluciones orientadas a tres etapas del proceso de obtención de data climática: adquisición de data, donde se capturan los datos; procesamiento, que corresponde al modelamiento predictivo de datos y delivery, que hace referencia al formato en el que se entrega la información. La precisión de los datos se traduce en mayor resolución, cobertura total a nivel nacional y mayor variedad de indicadores. Por su parte, el modelamiento define el factor diferencial más destacado: la inteligencia en el manejo de los datos, que permite entregar información más alineada a las necesidades del cliente. Finalmente, el delivery de información en tiempo y forma permitirá una toma de decisiones informada y oportuna. Sol 3 presenta un negocio sólido, con un alto potencial de rentabilidad, requiriendo un capital de CLP $576 millones, generando un VAN a perpetuidad de CLP $6.531 millones y de CLP $2.015 millones a periodo finito de cinco años, con una TIR de 49% y un payback de 2,8 años. Así, se concreta la misión de contribuir a mitigar los riesgos, maximizar oportunidades y perfeccionar la capacidad de adaptabilidad frente a estos fenómenos, promoviendo el desarrollo sustentable de sus clientes, inversionistas y sociedad.
cognom, nom. "Prova 3." Doctoral thesis, TDX (Tesis Doctorals en Xarxa), 2021. http://hdl.handle.net/10803/671804.
Повний текст джерелаLeipnitz, Guilhian. "Efeitos in vitro dos ácidos 3-hidroxi-3-metilglutárico, 3-metilglutárico, 3-metilglutacônico e 3-hidroxiisovalérico sobre parâmetros de estresse oxidativo em cérebro e fígado de ratos jovens." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17748.
Повний текст джерела3-Hydroxy-3-methylglutaric (HMGA) and 3-methylglutaconic (MGTA) acidurias are disorders that affect leucine catabolism and ketogenesis. HMGAaffected patients present tissue accumulation and high urinary excretion of 3- hydroxy-3-methylglutaric (HMG), 3-methylglutaric (MGA), 3-methylglutaconic (MGT) and 3-hydroxyisovaleric (OHIVA) acids, whereas MGTA is biochemically characterized by accumulation of MGT, MGA and OHIVA. MGTA- and HMGAaffected patients predominantly present neurologic symptoms. HMGA patients also present hepatomegaly, especially during metabolic crisis, which is characterized by a dramatic increase of the concentrations of the accumulating organic acids. Considering that the mechanisms of brain damage in HMGA and MGTA are poorly known, we first investigated the in vitro effects of HMG, MGA, MGT and OHIVA on important parameters of oxidative stress in cerebral cortex from young rats. We verified that the organic acids induced lipid peroxidation (thiobarbituric-acid reactive species, TBA-RS, and chemiluminescence increase) and protein oxidative damage (carbonyl formation and sulfhydryl oxidation) in cortical supernatants. The lipid peroxidation induced by HMG and MGT was prevented by the addition of free radical scavengers, suggesting that free radicals are involved in these effects. It was also demonstrated that HMG, MGA, MGT and OHIVA reduced non-enzymatic antioxidant defenses (reduced glutathione, GSH, concentrations, total radical-trapping antioxidant potential and total antioxidant reactivity) and that GSH decrease caused by HMG and MGA was prevented by free radical scavengers. On the other hand, the metabolites did not oxidize sulfhydryl groups from a commercial solution of GSH and from purified membrane protein-bound thiol groups, indicating that the decrease of GSH levels caused by the organic acids was not due to a direct oxidative effect. Next, we evaluated the vulnerability of a central (striatum) and a peripheral (liver) tissue to the oxidative damage caused by HMG, MGA, MGT and OHIVA. It can be observed that HMG, MGA, MGT and OHIVA induced lipid peroxidation (TBA-RS increase) in striatum. Among the various acids, only HMG increased TBA-RS in the liver. Furthermore, HMG induced the highest degree of lipid peroxidation in the striatum. It was also verified that the organic acids diminished GSH concentrations. Again, HMG presented the strongest effect compared to the other metabolites, reducing GSH levels in the striatum and in the liver. Finally, we observed that HMG, MGT and MGA reduced the sulfhydryl content (protein oxidation) in the striatum, whereas the metabolites did not alter this parameter in the liver. The present data indicate the HMG, MGA, MGT and OHIVA induce oxidative stress in cerebral cortex, striatum and liver from young rats. It can be also observed that the brain is more vulnerable than liver to lipid and protein oxidative damage induced by these organic acids, which is in agreement with the fact that the patients present predominantly neurologic symptoms. Therefore, it may be presumed that oxidative stress elicited in vitro by HMG, MGA, MGT and OHIVA contributes, at least in part, to the pathophysiology of the brain and hepatic damage found in HMGA and MGTA.
Escure, Pascale. "Elaboration de céramiques massives dans le système PbMg1/3 Nb2/3 O3-PbZn1/3 Nb2/3 O3-PbTiO3 : caractérisation structurale, propriétés électriques." Limoges, 1993. http://www.theses.fr/1993LIMO0202.
Повний текст джерелаEL, FARHI LARBI. "Étude de l'intercalation du lithium dans les composes lamellaires nips#3, in#2se#3, moo#3 et dans v#6o#1#3." Paris 6, 1993. http://www.theses.fr/1993PA066362.
Повний текст джерелаДмитрієв, Вадим Сергійович. "Омічні та інжектуючі бар’єрні переходи до арсеніду галію". Doctoral thesis, Київ, 2019. https://ela.kpi.ua/handle/123456789/29304.
Повний текст джерелаДисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.27.06 - Технологія, обладнання та виробництво електронної техніки. – Інженерний інститут Запорізького національного університету, Національний технічний університет України «Київський політехнічний інститут імені Ігоря Сікорського», 2019. Дисертаційну роботу присвячено розробці технології відтворюваного отримання омічних та інжектуючих бар’єрних переходів на основі срібла до арсеніду галію n-типу провідності. Розроблено технологію відтворюваного отримання омічних контактів Ag-Ge-In/n-n+GaAs, яка забезпечує лінійну ВАХ, коефіцієнт інжекції γ=0,07…0,00, контактний опір (5…7)∙10-5 Ом∙см2. Розроблено технологію відтворюваного отримання інжектуючих бар`єрних переходів Ag/n-n+GaAs з висотою потенційного бар’єру 0,98 В, коефіцієнтом інжекції γ =10-8, коефіцієнтом неідеальності η=1,087. Розроблені технології нанесення контактного матеріалу та режимів термообробки при створенні омічних та інжектуючих бар’єрних переходів рекомендуються до використання при виготовленні багатоелектродного МЕП-приладу з розширеними функціональними можливостями, до складу якого входять керуючі електроди, розташовані над областю розповсюдження біжучої хвилі.
Le, Chapelain Bertrand. "Conception d'une bibliothèque et d'un convolueur 3*3 TSPC." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/MQ48861.pdf.
Повний текст джерелаBrown, Andrew Peter. "Functional specificity of 14-3-3 proteins from tomato." Thesis, Lancaster University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436736.
Повний текст джерелаBrechin, C. "14-3-3 proteins and cholesterol-dependent membrane domains." Thesis, University of Edinburgh, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.641914.
Повний текст джерелаAnderson, William B. "The P-3 Scheduling Support System (P-3 S)/." Thesis, Monterey, California. Naval Postgraduate School, 1988. http://hdl.handle.net/10945/23085.
Повний текст джерелаMilton, Alasdair Hugh. "The regulation of E2F by 14-3-3 proteins." Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439225.
Повний текст джерелаVogel, Ursula Sigrid. "Molecular characterization of 2',3'-cyclic nucleotide 3'-phosphohydrolase." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330234.
Повний текст джерелаGallant, Amanda Jane. "New [3+3] Schiff-base macrocycles and their complexes." Thesis, University of British Columbia, 2006. http://hdl.handle.net/2429/30870.
Повний текст джерелаScience, Faculty of
Chemistry, Department of
Graduate
Chadeyron, Geneviève. "Syntheses et caracterisations spectrales d'orthoborates lnbo#3 (ln = la, y, in) dopes eu#3#+, tb#3#+." Clermont-Ferrand 2, 1996. http://www.theses.fr/1996CLF21855.
Повний текст джерелаCarelse, Mogamat Fahiem. "Comparative analysis of 3, 3'- diindolylmethane and indole-3-carbinol respective treatments in Brassica napus L." University of the Western Cape, 2017. http://hdl.handle.net/11394/5751.
Повний текст джерелаLately, there has been serious contamination of soils and ground water caused by mineral mining and environmental pollution leading to heavy metal accumulation within soils and over time rendering the soil infertile. The contaminated soil affects crop; yield, germination percentage and leads to seed dormancy. Additionally, as plants are sessile organisms, exposure to environmental stress involves different defense cycles and signalling molecules. Oxidative stress, increases the production of reactive oxygen species (ROS) at greater rates than that of the metabolism. Moreover, oxidative damage leads to the loss in cellular function and eventually death. Nonetheless, plants have adapted ROS-scavenging systems driven by reduction-oxidation reactions as defense mechanisms. In this way, cellular homeostasis is an essential defending process and finding means to optimize these reactions would benefit in the development of plants. Hence, environmentally friendly solutions are being reported such as using glucosinolates, a secondary plant metabolite found in relatively high concentrations within crucifers such as Brassica napus L.
2020-04-30
Zambon, Daniel. "Etude structurale et optique de la phase linay::(2)f::(8) : tb**(3+), eu**(3+), mecanisme de transfert tb**(3+) -> eu**(3+)." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF21088.
Повний текст джерелаMullen, Jerry D. (Jerry Davis). "A Comparison of Some Continuity Corrections for the Chi-Squared Test in 3 x 3, 3 x 4, and 3 x 5 Tables." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc331001/.
Повний текст джерелаБуряковський, Сергій Геннадійович. "Наукові основи вибору електроприводів стрілочних переводів для швидкісних та високошвидкісних залізниць". Thesis, Український державний университет залізничного транспорту, 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/29744.
Повний текст джерелаDoctoral thesis, technical sciences, specialty 05.22.09 – "Electric transport." National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The dissertation is dedicated to develop of theoretical bases for the selection and evaluation of the types of electric drives of turnouts operating in optimal modes, taking into account the nonlinearities of the load and the electrophysical properties of the engines, on the basis of solving the problem of minimizing the main quality indicators such as: the transfer time , the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The universal vector criterion for the working efficiency of the electric drive of turnouts is proposed. Its components are the transfer time, the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The assessment of the appropriateness of application a specific type of turnouts for rapid and high-speed traffic segments is made. The kinematic schemes in the form of two- and three-mass electromechanical systems with standard engines are considered. Various control systems for the operated electric drives, which provide higher quality indicators for rapidity of the switching process of the switch rails, positioning accuracy and the impact force on the rail, are proposed. The railway sleeper layout of the turnout with new types of electric motors is suggested to applying. The mathematical models for existing and prospective types of turnouts based on motors of rotational and linear types, which based on the solution of the Lagrange equation for electromechanical system taking into account the nonlinearity of the magnetic system, have been developed. The simulation models of electric drives of turnouts in the software environment of MATLAB SIMULINK on the basis of a DC motor, an asynchronous motor, a valve-inductor motor, a linear motor of electromagnetic type and a linear inductor motor are developed. The adequacy verification on physical models was made. The problem of analysis for determining the rational structure of the electric drive of turnout based on DC motor, asynchronous motor, valve-inductor motor, linear motor of electromagnetic type and linear inductor motor is formulated.
Буряковський, Сергій Геннадійович. "Наукові основи вибору електроприводів стрілочних переводів для швидкісних та високошвидкісних залізниць". Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/29739.
Повний текст джерелаDoctoral thesis, technical sciences, specialty 05.22.09 – "Electric transport." National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The dissertation is dedicated to develop of theoretical bases for the selection and evaluation of the types of electric drives of turnouts operating in optimal modes, taking into account the nonlinearities of the load and the electrophysical properties of the engines, on the basis of solving the problem of minimizing the main quality indicators such as: the transfer time , the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The universal vector criterion for the working efficiency of the electric drive of turnouts is proposed. Its components are the transfer time, the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The assessment of the appropriateness of application a specific type of turnouts for rapid and high-speed traffic segments is made. The kinematic schemes in the form of two- and three-mass electromechanical systems with standard engines are considered. Various control systems for the operated electric drives, which provide higher quality indicators for rapidity of the switching process of the switch rails, positioning accuracy and the impact force on the rail, are proposed. The railway sleeper layout of the turnout with new types of electric motors is suggested to applying. The mathematical models for existing and prospective types of turnouts based on motors of rotational and linear types, which based on the solution of the Lagrange equation for electromechanical system taking into account the nonlinearity of the magnetic system, have been developed. The simulation models of electric drives of turnouts in the software environment of MATLAB SIMULINK on the basis of a DC motor, an asynchronous motor, a valve-inductor motor, a linear motor of electromagnetic type and a linear inductor motor are developed. The adequacy verification on physical models was made. The problem of analysis for determining the rational structure of the electric drive of turnout based on DC motor, asynchronous motor, valve-inductor motor, linear motor of electromagnetic type and linear inductor motor is formulated.
Zhang, Lei. "Synthesis and characterization of relaxor-based piezo- and ferroelectric (1-x)Pb(Zn¦1¦/¦3Nb¦2¦/¦3)O¦3-xPbTiO¦3[PZN-PT] & (1-x)Pb(Mg¦1¦/¦3Nb¦2¦/¦3)O¦3-xPbTiO¦3[PMN-Pt]." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0009/MQ61521.pdf.
Повний текст джерелаOliveira, Higor Henrique de Souza [UNESP]. "Propriedades e mecanismos de cintilação dos materiais 'GD''AL''O IND.3' e ('GD''LU')'AL''O IND.3' dopados com 'EU POT. 3+', 'TB POT. 3+' e 'PR POT. 3+'." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/97926.
Повний текст джерелаCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Cintiladores são materiais capazes de absorver radiações de alta energia e convertê-las eficientemente em radiações ultravioleta ou visível. Avanços significativos na eletrônica de detecção dessas radiações motivaram as pesquisas visando à busca por novos materiais cintiladores de alta eficiência e à maior compreensão do mecanismo de cintilação. Nesse contexto, os compostos de matriz GdAlO3 e Gd1-xLuxAlO3 dopados com Eu3+, Tb3+ ou Pr3+ são materiais cintiladores promissores, pois apresentam alta densidade, elevados valores de coeficiente de atenuação de massa e propriedades espectroscópicas relevantes como emissão intensa, tempo de vida de mili ou microssegundos e transferência de energia a partir dos íons Gd3+ para os ativadores. Neste trabalho, foi investigada a preparação dos cintiladores GdAlO3 e Gd1-xLuxAlO3 nominalmente puros e dopados com Eu3+, Tb3+ e Pr3+ através do método dos precursores poliméricos (método Pechini) e suas propriedades estruturais e espectroscópicas (fotoluminescência e luminescência com excitação por raios X) foram investigadas. O perfil espectral de emissão das amostras de GdAlO3 dopadas com Eu3+ evidencia a ocupação de dois sítios distintos pelos íons dopantes quando em concentrações superiores a 1,0%-mol, provavelmente devido à distribuição não homogênea dos íons na matriz. A transferência de energia Gd3+→Ln3+ foi evidenciada pela espectroscopia de fotoluminescência e é um processo importante no mecanismo de cintilação desses materiais, como evidenciado pela comparação das medidas espectroscópicas de fotoluminescência e luminescência com excitação por raios X das amostras de GdAlO3:Pr3+. Com a incorporação de Lu3+ na matriz de GdAlO3, a intensidade de emissão aumenta até a concentração de 10%-mol de Lu3+, decrescendo...
Scintillators materials are compounds that can absorb ionizing radiations and efficiently convert them into UV-VIS radiations. Despite of impressive advances in the technology of direct detection, the search for new scintillators materials with high efficiency and for the precise understanding of the scintillation mechanism is still the focus of research in this area. In this context, the compounds GdAlO3 and Gd1-xLuxAlO3 doped with Eu3+, Tb3+ and Pr3+ are promising scintillators materials, since they have high density, high values of mass attenuation coefficient and relevant spectroscopic properties, such as bright emission, lifetime of milli or microseconds and the energy transfer from Gd3+ ions to the activators. This work describes the preparation of GdAlO3 and Gd1-xLuxAlO3 nominally pure and doped with Eu3+, Tb3+ e Pr3+ by the polymeric precursor method (Pechini method) and the study of their structural and spectroscopic (photoluminescence and X-rays excited optical luminescence) properties. Emission spectral profile of Eu3+-doped GdAlO3 indicates the occupation of two different sites by the dopant ions when the concentration is higher than 1.0 mol-%, probably due to inhomogeneous distribution of ions in the host. The energy transfer Gd3+→Ln3+ was evidenced by photoluminescence spectroscopy and is an important process in the scintillation mechanism of these materials, as showed by comparison of spectroscopic measurements of photoluminescence and X-rays excited optical luminescence of GdAlO3:Pr3+ sample. The emission intensity increases by incorporating Lu3+ in the GdAlO3 host until the Lu3+ concentration of 10 mol-%, decreasing at higher concentrations. This behavior is probably assigned to the balance between increasing the absorption of X-rays and the reduction of the transfer process from Gd3+ ions with increasing concentration of... (Complete abstract click electronic access below)
Oliveira, Higor Henrique de Souza. "Propriedades e mecanismos de cintilação dos materiais 'GD''AL''O IND.3' e ('GD''LU')'AL''O IND.3' dopados com 'EU POT. 3+', 'TB POT. 3+' e 'PR POT. 3+' /." Araraquara : [s.n.], 2011. http://hdl.handle.net/11449/97926.
Повний текст джерелаBanca: Carlos Frederico de Oliveira Graeff
Banca: Luiz Antonio de Oliveira Nunes
Resumo: Cintiladores são materiais capazes de absorver radiações de alta energia e convertê-las eficientemente em radiações ultravioleta ou visível. Avanços significativos na eletrônica de detecção dessas radiações motivaram as pesquisas visando à busca por novos materiais cintiladores de alta eficiência e à maior compreensão do mecanismo de cintilação. Nesse contexto, os compostos de matriz GdAlO3 e Gd1-xLuxAlO3 dopados com Eu3+, Tb3+ ou Pr3+ são materiais cintiladores promissores, pois apresentam alta densidade, elevados valores de coeficiente de atenuação de massa e propriedades espectroscópicas relevantes como emissão intensa, tempo de vida de mili ou microssegundos e transferência de energia a partir dos íons Gd3+ para os ativadores. Neste trabalho, foi investigada a preparação dos cintiladores GdAlO3 e Gd1-xLuxAlO3 nominalmente puros e dopados com Eu3+, Tb3+ e Pr3+ através do método dos precursores poliméricos (método Pechini) e suas propriedades estruturais e espectroscópicas (fotoluminescência e luminescência com excitação por raios X) foram investigadas. O perfil espectral de emissão das amostras de GdAlO3 dopadas com Eu3+ evidencia a ocupação de dois sítios distintos pelos íons dopantes quando em concentrações superiores a 1,0%-mol, provavelmente devido à distribuição não homogênea dos íons na matriz. A transferência de energia Gd3+→Ln3+ foi evidenciada pela espectroscopia de fotoluminescência e é um processo importante no mecanismo de cintilação desses materiais, como evidenciado pela comparação das medidas espectroscópicas de fotoluminescência e luminescência com excitação por raios X das amostras de GdAlO3:Pr3+. Com a incorporação de Lu3+ na matriz de GdAlO3, a intensidade de emissão aumenta até a concentração de 10%-mol de Lu3+, decrescendo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Scintillators materials are compounds that can absorb ionizing radiations and efficiently convert them into UV-VIS radiations. Despite of impressive advances in the technology of direct detection, the search for new scintillators materials with high efficiency and for the precise understanding of the scintillation mechanism is still the focus of research in this area. In this context, the compounds GdAlO3 and Gd1-xLuxAlO3 doped with Eu3+, Tb3+ and Pr3+ are promising scintillators materials, since they have high density, high values of mass attenuation coefficient and relevant spectroscopic properties, such as bright emission, lifetime of milli or microseconds and the energy transfer from Gd3+ ions to the activators. This work describes the preparation of GdAlO3 and Gd1-xLuxAlO3 nominally pure and doped with Eu3+, Tb3+ e Pr3+ by the polymeric precursor method (Pechini method) and the study of their structural and spectroscopic (photoluminescence and X-rays excited optical luminescence) properties. Emission spectral profile of Eu3+-doped GdAlO3 indicates the occupation of two different sites by the dopant ions when the concentration is higher than 1.0 mol-%, probably due to inhomogeneous distribution of ions in the host. The energy transfer Gd3+→Ln3+ was evidenced by photoluminescence spectroscopy and is an important process in the scintillation mechanism of these materials, as showed by comparison of spectroscopic measurements of photoluminescence and X-rays excited optical luminescence of GdAlO3:Pr3+ sample. The emission intensity increases by incorporating Lu3+ in the GdAlO3 host until the Lu3+ concentration of 10 mol-%, decreasing at higher concentrations. This behavior is probably assigned to the balance between increasing the absorption of X-rays and the reduction of the transfer process from Gd3+ ions with increasing concentration of... (Complete abstract click electronic access below)
Mestre
Parang, Keykavous. "Evaluation of myristic acid analogs and 5'-O-ester prodrugs of thymidine (dThd), 3'-azido-3'-deoxythymidine (AZT) and 3'-fluoro-3'-deoxythymidine (FLT)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq23054.pdf.
Повний текст джерелаCañero, Infante Ingrid. "(001) and (110) La(2/3)Ca(1/3)MnO(3) epitaxial ferromagnetic electrodes: a comparative study." Doctoral thesis, Universitat Autònoma de Barcelona, 2008. http://hdl.handle.net/10803/3407.
Повний текст джерелаAbad, Muñoz Libertad. "Efectos Estructurales y de Interfase en Capas Finas de La(2/3)Ca(1/3)MnO(3)." Doctoral thesis, Universitat Autònoma de Barcelona, 2007. http://hdl.handle.net/10803/3403.
Повний текст джерелаNuestro trabajo ha puesto de manifiesto que la técnica de pulverización catódica de RF es adecuada para el crecimiento de capas epitaxiales de LCMO de alta calidad sobre sustratos monocristalinos diversos (STO, LaAlO3 (LAO)). Las heteroestructuras LCMO/STO y LCMO/LAO han sido objeto de un detallado análisis poniendo de manifiesto que el desacoplo de parámetros de red juega un papel muy importante tanto sobre el tipo de crecimiento de las heteroestructuras como sobre las propiedades físicas. El sistema LCMO/STO (δ=1.2%) crece tensionado en el plano y permite crecer capas de hasta unos 100 nm sin que haya relajación parcial de la tensión estructural. En cambio, el sistema LCMO/LAO (δ=-1.8%) crece comprimido en el plano y muestra señales de relajación parcial de la tensión estructural incluso para espesores en torno a los 10 nm.
El análisis de las propiedades magnéticas y de transporte muestran que ambos sistemas LCMO/STO y LCMO/LAO adolecen de una notable disminución tanto de su temperatura de transición magnética, TC, como de su magnetización de saturación, MS, al disminuir el espesor de las capas, siendo éste más acusado en el caso del LCMO/STO. Tratamientos térmicos al aire a alta temperatura permiten una mejora sustancial de las propiedades magnéticas y de transporte en ambos sistemas. La mejora es mucho más rápida en el sistema LCMO/LAO. Así mismo, el aumento del espesor de las capas también promueve una mejora de las propiedades, que se aproximan a las del material en forma masiva conforme el grosor aumenta. Esta evolución se ha relacionado con la aparición de una capa no magnética en la superficie de las capas de LCMO que se pone de manifiesto, predominantemente para las capas de LCMO/LAO ultra delgadas. Por otro lado, hemos visto como esta capa inerte puede ser reducida hasta un orden de magnitud mediante tratamientos térmicos de las muestras a alta temperatura.
Nuestro trabajo ha puesto de manifiesto que la tensión estructural juega un papel fundamental y que las mejoras de TC y MS con los tratamientos térmicos están fundamentalmente ligadas a una relajación parcial de la tensión estructural. Otras posibilidades, tales como la incorporación de oxigeno o la variación de la microestructura de las muestras han sido descartadas en base a medidas de efecto Hall y análisis de microscopía electrónica de alta resolución.
Para el estudio de las propiedades de transporte en las interfases hemos desarrollado un procedimiento experimental basado en la utilización de un microscopio de fuerzas atómicas trabajando en modo corriente permitiendo la caracterización de barreras aislantes e interfases entre un metal noble y un óxido complejo. Este método permite la caracterización de barreras y superficies soslayando los problemas derivados del desconocimiento preciso del contacto entre la punta de AFM y la superficie de la capa. Se realizaron medidas mediante la definición de nanocontactos de diferente geometría y tamaño realizados por distintas técnicas de nanofabricación. Mediante el estudio de las curvas I(V) en nanocontactos de LCMO/metal noble (Au, Pt) constatamos la existencia de una barrera superficial aislante (túnel) para capas finas vírgenes de LCMO/LAO. Mediante el ajuste de las curvas I(V) utilizando el modelo de Simmons hemos derivado valores para la capa aislante que concuerdan muy bien con otros datos reportados, además esta capa aislante puede ser reducida drásticamente mediante tratamientos térmicos en atmósfera ambiente.
In this Thesis we have analyzed different preliminary aspects related to the use of complex oxides, such as manganes perovskites, for implementation of functional devices with potential application on magnetoelectronics. To be precise, we have faced in deep the different aspects related with the fabrication of magnetic tunnel junctions based on the La2/3Ca1/3MnO3 (LCMO)/SrTiO3 (STO) system.
Our work makes evident the suitability of RF sputtering technique for growing high quality epitaxial layers of LCMO onto several single-crystalline substrates (STO, LaAlO3 (LAO)). The heterostructures LCMO/STO and LCMO/LAO have been object of a detailed analysis showing up that structural misfit plays a significant role both on the heterostructures growth process and on the physical properties. The system LCMO/STO (δ=1.2%) is under in-plane tensile strain but, thin films up to 100 nm thick can be grown without any partial relieve of the structural strain. In contrast, the system LCMO/LAO (δ=-1.8%) grows under in-plane compressive strain and shows clear traces of partial relaxation of structural strain even for thicknesses around 10nm.
The analysis of the magnetic and transport properties indicates that both systems have an outstanding depression on both the temperature transition, TC, and the saturation magnetization, MS, when decreasing the thin film thickness, being this phenomenon more pronounced in the case of LCMO/STO. High temperature annealing processes in air promote a remarkable improvement of the magnetic and transport properties in both systems. This improvement is faster and more evident in the LCMO/LAO system.
In addition, we have verified that the increment of the film thicknesses also promotes an improvement of the physical properties, approaching that of bulk samples. This evolution has been correlated with the existence of a non magnetic layer at the topmost layers of the LCMO thin films, whose effect becomes more relevant as the film thickness decreases and being dominant for ultra-thin films in the LCMO/LAO system. It has been observed that this dead layer can be reduced up to one order of magnitude by high temperature annealing processes.
Our work has demonstrated that structural strain plays a fundamental role on the magnetic and transport properties of these systems and the improvements of TC and MS with annealing processes is strongly linked to a partial relaxation of the structural strain. Other possibilities, such as oxygen uptake or modifications of the microstructure of the samples have been ruled out in base of Hall Effect measurements and high resolution transmission electron microscopy analysis.
To study transport properties at the interfaces we have developed an experimental procedure based on the use of an atomic forces microscope (AFM) working in current sensing mode, permiting the electrical characterization of insulating barriers and the interfaces between the precious metal and the complex oxide. This method allows characterizing transport properties of barriers and interfaces avoiding the problems related to the uncertainty of the exact nature of the contact between the AFM tip an the analyzed surface. Measurements were realized by defining nanocontacts, with different geometries and sizes, using different nanofabrication techinques.
Palcut, Marián. "Cation diffusion in LaMnO3, LaCoO3 and LaFeO3 materials." Doctoral thesis, Norwegian University of Science and Technology, Department of Materials Technology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1819.
Повний текст джерелаAlvarez, David 1971. "The involvement of CBP/14-3-3 in DNA replication /." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82819.
Повний текст джерелаCBP was previously shown to contain the β, ɣ, ε, and ζ isoforms of the 14-3-3 family, which is composed of seven mammalian isoforms (β, ɣ, ε, η, σ, τ, and ζ) that can form homo- and heterodimers, and plays a variety of roles in different cellular processes. In this thesis, I showed by Western blot analysis with anti-14-3-3σ antibody, which partially interfered with the CBP-cruciform DNA complex formation, that the isolated CBP-cruciform DNA complex contained also the σ isoform. The same antibody reduced the in vitro DNA replication efficiency of HeLa cell total extracts, in an assay that used p186, a plasmid bearing the 186-bp minimal origin of ors8, as template DNA. Similarly, I found that antibodies against 14-3-3 isoforms β, ɣ, ε, and ζ also interfered with the CBP-cruciform DNA complex formation, and reduced the in vitro p186 replication efficiency of HeLa cell total extracts. The five isoforms of 14-3-3 (β, ɣ, ε, σ, and ζ) were found to associate with the monkey cell (CV-1) origins of DNA replication ors8 and ors12 in a cell cycle-dependent manner, the association being higher at the G1/S phase. Furthermore, we found that 14-3-3 yeast homologues, Bmh1p and Bmh2p, were able to bind cruciform DNA in vitro, and to associate in vivo with the autonomous replication sequence 307 (ARS307) in a cell cycle-dependent manner, again the association being higher at G1/S. Finally, I showed that recombinant 14-3-3ζ, tagged with maltose-binding protein (r14-3-3ζ-MBP), could only bind cruciform DNA after pre-incubation with a CBP-enriched HeLa cell extract (FTH), in which it heterodimerized with endogenous 14-3-3 isoforms β and ε. Addition of r14-3-3ζ-MBP to HeLa cell total extracts increased the in vitro replication of p186, suggesting that increased CBP activity could lead to multiple rounds of initiation of DNA replication.
Kent, Christopher. "14-3-3 proteins regulate axonal growth cone turning repsonses." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114302.
Повний текст джерелаLa projection des axones vers leurs cibles appropriées au cours du développement ou de la régénération s'appuie sur le cône de croissance, une structure spécialisée qui intègre les signaux extracellulaires pour guider la croissance axonale. La mise en place des connexions multiples et complexes formées par le système nerveux, tout en s'appuyant sur un nombre limité de signaux, requière que le cône de croissance module sa réponse à ces signaux tant dans l'espace que dans le temps. Les mécanismes par lesquels le cône de croissance est en mesure réguler la réponse spacio-temporelle de son cytosquelette à des signaux de guidage commencent seulement à être compris. L'analyse protéomique de cônes de croissance isolés a identifié les protéines adaptatrices 14-3-3 en tant que constituants principaux du cône de croissance. Compte tenu de leur rôle dans la régulation de l'activité spatiale et temporelle de multiples événements de signalisation cellulaires, les protéines 14-3-3 sont d'excellents candidats pour jouer un rôle similaire dans le cône de croissance. Cette thèse établit le rôle essentiel des protéines 14-3-3 dans la régulation spatiale et temporelle de la réponse du cône de croissance à des signaux de guidage axonal. Dans le chapitre 2, nous décrivons comment la perte de fonction des protéines 14-3-3 dans les neurones du ganglion de la racine dorsale (DRG), convertit leur réponse à des gradients de facteur de croissance nerveuse (NGF) et glycoprotéine associée à la myéline (MAG) de la répulsion à l'attraction. Ce commutateur peut être bloqué par l'inactivation de la kinase dépendante à AMPc (PKA), ce qui implique 14-3-3 dans la régulation de l'activité de PKA. Dans ce sens, nous constatons que les protéines 14-3-3 interagissent avec PKA et que perturber cette interaction résulte en la libération de sous-unités catalytiques actives de la PKA. Dans le chapitre 3, nous décrivons le rôle des protéines 14-3-3 et de PKA dans l'établissement d'un commutateur intrinsèque à la cellule, et dépendant du temps lors de l'orientation des axones des interneurones commissuraux soumis à un gradient de Sonic Hedgehog (Shh). Le changement d'une réponse attractive à une réponse répulsive à SHH au niveau de la ligne médiane est essentiel à la formation des projections axonales appropriées des neurones commissuraux dorsaux de la moelle épinière lors du développement, et interférer avec ce commutateur in vivo, soit en surexprimant prématurément les 14-3 – 3, soit en bloquant la fonction des 14-3-3, entraîne une croissance axonale aberrante. Dans le chapitre 4, nous identifions un rôle pour les protéines 14-3-3 dans la médiation d'un autre signal de guidage utilisé par les neurones commissuraux, la nétrine-1. Ensemble, ces études montrent que les protéines 14-3-3 sont une famille multifonctionnelle de protéines adaptatrices qui fournissent un niveau supplémentaire de régulation du guidage axonal, permettant au cône de croissance de répondre à des signaux de façon appropriée au cours du développement et de fournir une cible potentiellement intéressante pour la modulation de cette croissance après blessure axonale.
Yeung, Shu-wai. "Analysis of 14-3-3 [sigma] protein in nasopharyngeal tissues." Click to view the E-thesis via HKUTO, 2003. http://sunzi.lib.hku.hk/hkuto/record/B31971398.
Повний текст джерелаThiel, Stefan Patrick. "Study of interface properties in LaAlO 3, SrTiO 3 heterostructures." kostenfrei kostenfrei, 2009. http://d-nb.info/994511116/34.
Повний текст джерелаCarrocci, Tucker Joe. "Sythesis and Characterization of 3-(3-Hydroxyalkanoyloxy)alkanoic acids (HAAs)." Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/144240.
Повний текст джерела