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Optimisation et compréhension des dispositifs à base de Cu2ZnSn(Sx,Se1-x)4 pour applications photovoltaïques en couches minces / Optimization and understanding of Cu2ZnSn(Sx,Se1-x)4 based devices for thin films photovoltaic applicationsTemgoua, Solange 08 November 2016 (has links)
Ce travail s'inscrit dans une stratégie de développement de matériaux abondants, non toxiques, pour le photovoltaïque. Le Cu2ZnSn(S,Se)4 (CZTSSe) est un matériau qui répond à tous ces critères et est de ce fait, un candidat très prometteur. Parmi les techniques utilisées pour synthétiser le CZTSSe, le procédé en deux étapes (dépôt du précurseur + recuit) semble être le plus adapté pour l'obtention de meilleurs rendements. L'objectif de cette thèse est de développer et d'optimiser un procédé de fabrication pour la synthèse d'absorbeurs CZTSSe intégrés à des dispositifs photovoltaïques. Pour atteindre ce but, différentes études ont été réalisées. Premièrement, le mécanisme de formation du matériau a été étudié en fonction des conditions de synthèse ; plus précisément l'intérêt était porté sur les réactions ayant lieu pendant la montée en température. Cela a permis de comprendre que la vitesse de chauffe était un paramètre déterminant lors du recuit, car elle affectait la cinétique de formation des composés binaires, ternaires et quaternaires. Plus intéressant encore, cette étude a mis en lumière une forte affinité chimique entre les vapeurs de sélénium et l'étain qui domine sur l'affinité entre le cuivre et le sélénium gazeux. Ensuite, différents absorbeurs ont été fabriquées en modifiant des paramètres telles que l'épaisseur du précurseur, l'atmosphère de recuit, les traitements chimiques pour optimiser les paramètres électriques. Des rendements de 8% ont été obtenus pour des cellules à base de CZTSe et 7,1% sur celles à base de CZTSSe, avec de très bonnes homogénéités. Un rendement de 2,3% a été obtenu sur une architecture nouvelle intégrant les TCO comme contact arrière. / This work is part of a strategy to develop abundant, non-toxic, for photovoltaics. The Cu2ZnSn(S,Se)4 (CZTSSe) is a material that meets all these criteria and is therefore a very promising candidate. Among the techniques used to synthesize the CZTSSe, the two-step process (deposition of precursor + annealing) seems to be the most suitable for obtaining higher efficiencies. The objective of this thesis is to develop and optimize a method for the synthesis of CZTSSe absorbers integrated into photovoltaic devices. To achieve this purpose, various studies have been carried out. First, the formation mechanism of CZTSSe has been studied as a function of the synthesis conditions; more precisely the interest was focused on reactions taking place during the rise in temperature. This helped to understand that the heating rate was a critical parameter during annealing because it affected the formation kinetics of binary, ternary and quaternary compounds. More interestingly, this study has highlighted a strong chemical affinity between selenium vapors and tin which dominates the affinity between copper and selenium gaseous species. Then, different absorbers were synthesized by changing parameters such as the thickness of the precursor, the annealing atmosphere and chemical treatments to optimize the electrical parameters. 8% efficiency was obtained for CZTSe-based solar cells and 7.1% of those based on CZTSSe, with very good homogeneity. A 2.3% efficiency was obtained on a new architecture integrating TCO thin films as back contact.
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Evaluating the Vector Supercomputer SX-Aurora TSUBASA as a Co-Processor for In-Memory Database SystemsPietrzyk, Johannes, Habich, Dirk, Damme, Patrick, Focht, Erich, Lehner, Wolfgang 16 June 2023 (has links)
In-memory column-store database systems are state of the art for the efficient processing of analytical workloads. In these systems, data compression as well as vectorization play an important role. Currently, the vectorized processing is done using regular SIMD (Single Instruction Multiple Data) extensions of modern processors. For example, Intel’s latest SIMD extension supports 512-bit vector registers which allows the parallel processing of 8× 64-bit values. From a database system perspective, this vectorization technique is not only very interesting for compression and decompression to reduce the computational overhead, but also for all database operators like joins, scan, as well as groupings. In contrast to these SIMD extensions, NEC Corporation has recently introduced a novel pure vector engine (supercomputer) as a co-processor called SX-Aurora TSUBASA. This vector engine features a vector length of 16.384 bits with the world’s highest bandwidth of up to 1.2 TB/s, which perfectly fits to data-intensive applications like in-memory database systems. Therefore, we describe the unique architecture and properties of this novel vector engine in this paper. Moreover, we present selected in-memory column-store-specific evaluation results to show the benefits of this vector engine compared to regular SIMD extensions. Finally, we conclude the paper with an outlook on our ongoing research activities in this direction.
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Single Atom X-ray Spectroscopy of Rare-Earth Metals: La and Tb ComplexesSOTTIE, RICHARD 05 June 2023 (has links)
No description available.
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Biologia reprodutiva do dourado, Coryphaena hippurus (Linnaeus, 1758), no arquipélago de São Pedro e São Paulo, BrasilSANTOS, Andréa Carla Lira dos 24 February 2012 (has links)
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Previous issue date: 2012-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The dolphinfish, Coryphaena hippurus, an oceanic pelagic species with circumtropical distribution, is an important fishery resource around the world. The Archipelago of St Peter and St Paul plays an important role in the migratory route of several species of high commercial value, including the dolphinfish. In this context, studies of reproductive biology may help conservation and management of these stocks by providing essential information, such as the size at first sexual maturity and spawning season. In this study, a total of 861 individuals were examined, 811 of which were sexed (279 female and 532 male). Of these, the stage of sexual maturity was identified in 565 specimens. The fork length (FL) of specimens ranged between 27 and 150 cm, with a sex ratio of 1 male to 1.9 females. The distribution of average monthly Gonadal Index of adults ranged between 0.58 and 3.73 for males and between 3.22 and 34.90 for females. Size at first sexual maturity (L50) was estimated at 68.8 cm FL, for males, and 67.7 cm FL, for females. The results suggest that the period of greatest reproductive activity occurs between April and June. / O dourado, Coryphaena hippurus, é uma espécie pelágica e oceânica com distribuição circumtropical, que representa um importante recurso pesqueiro em todo o mundo. O Arquipélago de São Pedro e São Paulo se encontra na rota migratória de várias espécies de elevado valor comercial, entre elas o dourado. Diante desse contexto os estudos de biologia reprodutiva representam uma ferramenta útil para o auxílio da conservação e gestão desses estoques através do aporte de informações, como, por exemplo, tamanho de primeira maturação sexual e época de desova. Nesse trabalho, 861 indivíduos de dourado foram examinados, dos quais 811 foram sexados (279 machos e 532 fêmeas), tendo sido identificados os estágios de maturação gonadal de 565. O comprimento zoológico dos exemplares variou entre 27 e 150 cm, com proporção sexual de 1 macho para 1,9 fêmeas. A distribuição da média mensal do Índice Gonadal dos indivíduos adultos variou entre 0,58 e 3,73 para os machos e entre 3,22 e 34,90 para as fêmeas. O comprimento de primeira maturação sexual (L50) foi estimado em 68,8 cm de Comprimento Zoológico (CZ), para os machos, e 67,7cm de CZ, para as fêmeas. Os resultados sugerem que o período de maior atividade reprodutiva ocorre entre abril e junho.
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Analysis of mice deficient in late endosomal SNARE proteins VAMP8/endobrevin and Vti1b / Analysis of mice deficient in late endosomal SNARE proteins VAMP8/endobrevin and Vti1bKanwar, Namita 12 January 2007 (has links)
No description available.
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Simulace dopravy za využití dopravních řadičů / Traffic Simulation Using Traffic ControllersDressler, David January 2019 (has links)
The aim of this master's thesis is to design an extension of the existing simulation system for designing traffic intersections. The required extension will allow the use of the Siemens sX traffic controllers. The introduction to the topic of traffic engineering, traffic controllers configuration and the dynamic traffic control is discussed first. The next part is dedicated to describing the implementation of the existing simulation system. The following chapter describes the use of the sX traffic controllers and also describes the design of the required extension of the existing simulation system, for a purpose of enabling the use of sX traffic controllers. This is followed by a chapter describing the implementation of this extension. The last chapter is devoted to testing the whole system in terms of functionality and performance. Finally, other possibilities for the future development are outlined.
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Ekstrakcija ginka (Ginkgo biloba L.) ugljenik (IV)-oksidom pod pritiskom / Extraction of Ginkgo biloba L.by carbon (IV) –oxide under pressureMilošević Svetlana 27 May 2011 (has links)
<p>U okviru ove disertacije izvršeno je preparatvno izolovanje etarskog ulja lišća ginka (<em>Ginkgo biloba</em> L.) destilacijom pomoću vodene pare, u cilju određivanja pojedinih fizičko-hemijskih parametara. Oficinalnim postupkom određen je sadržaj etarskog ulja u lišću ginka i iznosi 0,0083%. Lišće ginka je ekstrahovano klasičnim rastvaračima tj. smešom alkohol-voda, pri čemu je koncentracija alkohola iznosila 40% (m/m). Primenom navedenog rastvarača, izvršena je višestupna protivstrujna ekstrakcija (u pet stupnjeva) pri čemu je dobijen tečni ekstrakt (<em>Extracta fluida</em>) sa relativno visokim sadržajem ekstraktivnih materija (17,06%). Tečni ekstrakt je direktno korišćen za dobijanje suvog ekstrakta lišća ginka (<em>Extracta sicca</em>)primenomvsušnie sa raspršivanjem (spray dryer). Kvalitativna i kvantitativna karakterzacija izvršena je primenom postupka tečne hromatografije na tankom sloju (HPTLC) i određen sadržaj ukupnih flavonoida sračunatih na rutin, a i na katehin, a određen je i sadržaj ukupnih fenola sračunatih na hlorogensku kiselinu. Glavni deo doktorske disertacije predstavlja ekstrakcija sistema lišće ginka-ugljenik (IV)-oksid pod pritiskom, pri čemu je ispitivan uticaj stepena usitnjenosti droge na prinos ekstrakcije, i korišćen koeficijent brze i spore ekstrakcije kao mera kinetičkog ponašanja ekstrakcije. Dobijeni rezultati ispitivanja su pokazali značajan uticaj stepena usitnjenosti droge na brzinu ekstrakcije, pogotovo, kod ekstrakcije natkritičnim ugljenik (IV) oksidom. Radi izbora optimalnog protoka ekstragensa ispitivani su sledeći protoci 0,095, 0,194 i 0,277 kg/h . Na osnovu prinosa ekstrakcije usvojeno je da je protok ekstragensa od 0,194 kg/h optimalan. Prinos ekstrakcije je ispitivan korišćenjem dva postupka ekstrakcije, i to: ekstrakcija tečnim ugljenik (IV) -oksidom (temperatura ispod kritične temperature Tc= 31,1<sup>o</sup>C, a pritisak nešto ispod ili iznad kritičnog pritiska p<sub>c</sub>=73,8 bar), i ekstrakcija natkritičnim ugljenik (IV)- oksidom (pritisak i temperatura iznad kritičnih vrednosti pritiska i temperature). U natkritičnoj oblasti promenom pritiska se značajno menjaju svojstva ekstragensa, povećava se sposobnost rastvaranja, dielektrična konstanta i dr. Ispitivan je uticaj temperature na prinos ekstrakcije (izotermni proces), pri čemu se dobijaju rezultati koji se ne mogu objasniti jednostavno, analizirajući samo uticaj gustine rastvarača na moć rastvaranja, već se za objašnjenje dobijenih rezultata uključuje i uticaj napona pare ekstrahovane komponente, tako da rastvorljivost komponente može da se poveća, smanji ili ostane ista sa povećanjem temperature na konstantnom pritisku, u zavisnosti koji uticaj je dominantniji. Kod izotermnih postupaka prinos ekstrakcije raste sa povećanjem pritiska ekstrakcije, što je u saglasnosti sa teoretskim principima. S druge strane, ekstrakti dobijeni pri višim pritiscima imaju manji sadržaj etarskog ulja što se objašnjava činjenicom da veći pritisci imaju veću moć rastvaranja glavnih komponenata kao i komponenata kao što su smole, voskovi i masna ulja. Kvalitativnom i kvantitativnom analizom selektovanih ekstrakata dobijenih tečnim (130 bar, 20<sup>o</sup>C, 3 h) i natkritičnim (100 bar, 40<sup>o</sup> C, 4 h) ugljenik (IV)-oksidom, kao i etarska ulja izolovana iz ovih ekstrakata nađeno je da ispitivani uzorci sadrže nalkane, račvaste alkane i jedinjenja sa kiseonikom, među kojima posebno mesto zauzimaju fenoli sa zasićenim i nezasićenim alkil ostacima.<br />Izvršena je uporedna anliza etarskog ulja dobijenog destilacijom lišća ginka pomoću vodene pare i etarskih ulja dobijenih iz selektovanih ekstrakata. Interesantan je podatak koji se odnosi na sadržaj etarskog ulja u drogi određen direktnom destilacijom droge pomoću vodene pare i izdvajanjem etarskih ulja iz ekstrakata takođe destilacijom pomoću vodene pare. U ovom drugom slučaju dobija se, preračunavanjem, sadržaj etarskog ulja u drogi višestruko veći (4-10 puta) od sadržaja, određenog oficinalnim postupkom, u drogi. Ova pojava se objašnjava uvođenjem pojma „vezano“ etarsko ulje i „slobodno“ etarsko ulje. Ekstrakcijom ugljenik (IV)-oksidom pod pritiskom tzv. vezano etarsko ulje se oslobađa voskova i masnog ulja što se odražava na njegovu povećanu količinu u CO<sub>2</sub>-ekstraktima. Na kraju u ovoj disertaciji izvršeno je modelovanje ekstrakcionog sistema lišće <em>Ginkgo biloba</em> – ugljenik (IV)-oksid pod pritiskom korišćenjem model jednačine Naika i saradnika, modifikovane model jednačine Reverchon i Sesti-Osseo kao i model, češće korišćen, koji je predložila Sovová. Korišćeni modeli mogu relativno uspešno da se koriste za opisivanje ekstrakcionog sistema lišće <em>Ginkgo biloba</em> – ugljenik (IV)-oksid pod pritiskom. Radi iznalaženja najpovoljnijih uslova ekstrakcije primenjen je metod odzivne površine variranjem parametra ekstrakcije (pritisak, temperatura i vreme ekstrakcije). Na osnovu eksperimentalnih rezultata dobijen je polinom drugog reda za izračunavanje optimalnog prinosa ekstrakcije i određeni su najpovoljniji uslovi ekstrakcije kao i međusobni uticaji pojedinih parametra.</p> / <p>Within this thesis preparative isolation of essential oil from leaves of ginkgo (<em>Ginkgo biloba</em> L.) by steam distillation was carried out, in order to determine some physico-chemical parameters. The essential oil content in the leaves of ginkgo wass determined by an officinal procedure and its value is 0.0083%. Ginkgo leaves were extracted with conventional solvents, i.e. alcohol-water mixture, where the alcohol concentration was 40% (w/w). The forementioned solvent was used to carry out a multistage counter-current extraction (five stages) by which the liquid extract (<em>Extracta fluida</em>) with a relatively high content of extracts (17.06%) was obtained. The liquid extract was directly used to obtain a dry extract of ginkgo leaves (<em>Extracta sicca</em>) by spay drying. The qualitative and quantitative characterisation was based on the proceedings of liquid thin layer chromatography (HPTLC), the content of total flavonoids expressed as rutin, and as catechin, and the total phenol content expressed as chlorogenic acid was determined. The main part of the doctoral thesis is the extraction system of ginkgo leaves-carbon (IV) oxide under pressure, in which the effect of the drug particle size on the extraction yield was studied, and as a measure of the kinetic behavior of extraction the coefficient of fast and slow extraction was used. The obtained results showed a significant effect of the drug particle size on the speed of extraction, particularly, the extraction with supercritical carbon (IV) oxide. For the purpose of selecting the optimal flow of the solvent several flowrates were investigated 0.095, 0.194 and 0.277 kg/h. Based on the yield of extraction the solvent flowrate of 0.194 kg/h was assumed as optimal. The extraction yield was investigated using two extraction procedures: extraction with liquid carbon (IV) oxide (temperature below the critical temperature Tc = 31.1 <sup>0</sup>C and pressure slightly below or above the critical pressure p<sub>c</sub> = 73.8 bar), and extraction with supercritical carbon (IV) oxide (pressure and temperature above the critical values of pressure and temperature). In the supercritical area the change in pressure significantly the influences the properties of the solvent, increases the ability of dissolving, dielectric constant, etc. The effect of temperature on extraction yield was examined (isothermal process), where the obtained results can not be explained simply by analyzing only the effect of solvent density on the power of dissolution, but to explain these results the effect of vapor pressure of the extracted components must be included, so that the solubility of the component may increase, decrease or remain the same with increasing temperature at constant pressure, depending on which influence is dominant. In isothermal processes the extraction yield increases with increasing pressure of extraction, which is consistent with theoretical principles. On the other hand, extracts obtained at high pressures have a lower content of essential oils which can be explained by the fact that higher pressures have a greater power of dissolution of the main components as well as components such as resins, waxes and fatty oils. The qualitative and quantitative analysis of the selected extracts obtained with liquid (130 bar, 20 <sup>0</sup>C, 3 h) and supercritical (100 bar, 40 <sup>0</sup>C, 4 h) carbon (IV) oxide, and essential oils isolated from these extracts showed that the studied samples contain n-alkanes, branched alkanes and compounds with oxygen, including phenols with saturated and unsaturated alkyl residues. A comparative analysis of the essential oil obtained by distillation of ginkgo leaves by steam and essential oil obtained from selected extracts was carried out. An interesting fact concerning the essential oil content in the drug determined by direct distillation of drugs by steam and separating the essential oils from extracts also produced by steam distillation. In the other case, by calculation, the obtained essential oil content in the drug is several times higher (4-10 times) of content, determined by an fficinal procedure, in the drug. This phenomenon is explained by introducing the notion of "linked" essential oil and "free" essential oil. The extraction with carbon (IV) oxide under pressure the so called linked essential oil is released from waxes and fatty oils which is reflected in its increased amount in CO<sub>2</sub>-extracts. At the end of this dissertation the modeling of the extraction system leaves of <em>Ginkgo biloba</em> - carbon (IV) oxide under pressure was carried out using the model equation of Naik and associates, the modified model equation of Reverchon and Sesti Osseo and also like a frequently used model proposed Sovová. The mentioned models can be relatively used to describe the extraction system leaves of <em>Ginkgo biloba</em> - carbon (IV) oxide under pressure. In order to find the most favorable conditions of extraction, the response surface methodology varying extraction parameters was used (pressure, temperature and extraction time). Based on the experimental results a second order polynom for the calculation of the optimum yield of extraction was obtained and the extraction conditions and the mutual influence of some parameters were determined.</p>
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Dynamische Strukturen am Zellcortex: Aktivierbarkeit und Akkumulation von Ezrin in Abhängigkeit von PIP2 / Dynamic structures at the cell cortex: activation and accumulation of ezrin depending on PIP2Bosk, Sabine 18 March 2011 (has links)
No description available.
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Entwicklung eines Fusionsassays basierend auf porenüberspannenden Membranen / Development of a fusion assay based on pore-spanning membranesHöfer, Ines 05 July 2011 (has links)
No description available.
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Targeting and Anchoring of Munc13-1 and ubMunc13-2 to active zones by RIM1alpha / Targeting and Anchoring von Munc13-1 und ubMunc13-2 zu active zones durch RIM1alphaAndrews-Zwilling, Yaisa 21 October 2005 (has links)
No description available.
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