To see the other types of publications on this topic, follow the link: Doping analysis.
Dissertations / Theses on the topic 'Doping analysis'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Doping analysis.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Myers, Joseph Kenneth. "Inverse doping profile analysis for semiconductor quality control." Diss., Wichita State University, 2009. http://hdl.handle.net/10057/2556.
Full textAbstract:
Inverse doping pro le problems are linked to inverse conductivity problems under the
assumptions of zero space charge and low injection. Unipolar inverse conductivity problems
are analyzed theoretically via three uniqueness proofs, the rst of which has been
published as a paper in Inverse Problems [34]. Also, optimized numerical methods are
developed for solving the unipolar direct conductivity problem with a piecewise constant
conductivity coe cient. Finally, the unipolar inverse conductivity problem is solved for
inclusions de ned by as many as 9 parameters, or by as many as 120 parameters when an
initial guess for each parameter is known with less than 10% error. Our free boundary
identi cation algorithm produces a sequence of improved approximations in a way that
provides both regularization and accelerated convergence towards the solution.Thesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Mathematics and Statistics
2
Jackson, Keith M. (Keith Matthew). "Laterally non-uniform doping profiles on MOSFETs : modeling and analysis." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41415.
Full text
3
Williams, Samuel Thomas. "Analysis of erythropoietin for anti-doping purposes with a focus on hyphenated techniques." Thesis, King's College London (University of London), 2014. https://kclpure.kcl.ac.uk/portal/en/theses/analysis-of-erythropoietin-for-antidoping-purposes-with-a-focus-on-hyphenated-techniques(8b6d26e7-a9c5-4d5a-9e3a-f32be79939e2).html.
Full textAbstract:
To improve detection of the misuse of erythropoietin (EPO) for performance enhancing purposes, this PhD examined ways to improve recovery and preanalysis concentration of EPO from urine. It also looked at ways to enhance the signal in liquid chromatography tandem mass spectrometry of the acidic glycopeptides from digested EPO, and at distinguishing between recombinant EPO and human urinary EPO based on differences in their glycosylation. Due to a shortage of supply of available analytical standards, model glycoproteins were frequently used in place of endogenous EPO. Immunoextraction with magnetic beads effectively recovered EPO from urine which had been filtered to remove large proteins, but was unsuccessful from unfiltered urine, suggesting more research into the right choice of antibody was needed. The specific and reversible binding of boronic acids to cis-diol groups found in the glycan groups of glycoproteins was investigated as a device for the selective binding of EPO. Attempts were made to functionalise mesoporous silica for use as a column packing material. Although there was evidence that at least one method of functionalisation was successful, the use of this silica to extract glycoproteins and glycopeptides was not. Signal enhancement through the introduction of ‘superchargers’ into LC solvents was investigated. This was effective with small molecules, and also improved detection of sialylated glycopeptides. The results do not fit entirely with current models of how superchargers exert their effect, suggesting they are incomplete. Finally, the cleavage, digestion and derivatisation of N-glycans to identify bisected and non-bisected structures as a way to discriminate between rEPO and huEPO was examined. Samples were analysed using LC-MS and CE-LIF, and although much of the work was carried out using a model glycoprotein, there is some evidence that the approach may be capable of discriminating between artificial and endogenous EPO at the levels found in anti-doping samples.
4
MacGregor, Oskar. "Anti-doping, whereabouts, and privacy : an ethico-legal analysis of WADA's whereabouts requirements." Thesis, Swansea University, 2013. https://cronfa.swan.ac.uk/Record/cronfa42914.
Full textAbstract:
The World Anti-Doping Agency (WADA) is the primary global organization responsible for implementing rules against doping in sport. A central element of its mission is the requirement that elite athletes submit their whereabouts information for every day of the year to their relevant Anti-Doping Organization (ADO), in order to facilitate no advance notice out-of-competition doping testing. These requirements have attracted considerable criticism, including the claim that they invade elite athlete privacy in a legally or ethically unacceptable manner. The validity of these claims is threatened by the contestedness of the concept of privacy, which arises from the many different uses to which the concept is put, including in legal and philosophical contexts. Resolving this conceptual confusion requires taking an explicit position on various questions of philosophical methodology, themselves subject to contention. As an alternative to such abstraction, and particularly given the need for a philosophically defensible yet pragmatic policy application, I argue that privacy is best conceived of as the absence of certain contextually relevant harms to the person, which arise in relation to such underlying normative values as fairness between competing athletes. In the specific context of elite athlete whereabouts requirements, I maintain that privacy concerns arise principally in relation to surveillance, intrusion, and breaches of confidence. Of these, the first and second face legal difficulties in the UK, on the basis of European legislation concerning human rights and maximum working time. Ethical problems also arise due to WADAs undifferentiated application of the whereabouts requirements, which ignores the heterogeneity of different types of sports and their respective vulnerabilities to doping. I argue that WADAs whereabouts requirements ought therefore to be revised to (a) ensure that they do not conflict with established law, and (b) respect the very different sets of circumstances entailed by the heterogeneous world of elite sports.
5
Li, Kaile. "Defects at surface and interface of crystals : theoretical and x-ray scattering analysis /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3074422.
Full text
6
Such, Sanmartin Gerard. "Assessing human growth hormone variants to determine their potential relevance in anti-doping and clinical analysis." Doctoral thesis, Universitat Pompeu Fabra, 2010. http://hdl.handle.net/10803/7198.
Full textAbstract:
Human growth hormone (GH) participates in human longitudinal growth, lipid and carbohydrate metabolism, and comprises a remarkably number of proteins with similar sequences, generated either genetically or post-translationally, that in some cases show clearly differentiated biological activities. Current methods employed for its quantification are mainly based on a specific immunodetection of the most concentrated GH variants in blood circulation. However, it is not clear neither which variants are recognised in each case, nor which is the real concentration of some of these variants. Probably related, present immunoassays show a disparity of results between them that difficults the comparison of data from different assays, with direct consequences in the clinical field. Within a doping context, the illegal administration of recombinant GH constitutes a complex challenge, given the fact that the pharmaceutical variant and the native 22 kDa GH variant do not show any structural difference that allows a direct detection. However, the administration of the pharmaceutical inhibits the natural production of the hormone, resulting in modifications between the relative concentration of some of these variants. In this case, which variants are detected is of utmost importance, since these constitute the base of this anti-GH doping method. Here, the relevance of some GH variants is addressed, including their generation, characterisation, analysis through specific antibodies and their detection on biological samples.L'hormona de creixement humana (GH) participa en el creixement post-longitudinal i en el metabolisme de lípids i carbohidrats, i comprèn un extraordinari nombre de proteïnes de seqüències similars, generades tant genèticament com posttranslacional, que en alguns casos mostren activitats biològiques clarament diferenciades. Els mètodes actuals emprats per la seva quantificació es basen principalment en una immunodetecció específica de les variants de GH més concentrades en circulació sanguínia. Tanmateix, no resta clar quines variants es reconeixen en cada cas, ni quina és la concentració real d'algunes d'aquestes variants. Possiblement relacionat, els immunoassaigs actualment utilitzats mostren una disparitat de resultats que dificulten la comparació de dades d'assaigs diferents, amb conseqüències directes en el camp clínic. Dins d'un context de dopatge, l'administració il·legal de GH recombinant constitueix un desafiament complex, donat el fet que la variant farmacèutica i la variant de GH nativa de 22 kDa no mostren cap diferència que permeti una detecció directa. No obstant, l'administració del medicament farmacèutic inhibeix la producció natural de la hormona, derivant en canvis entre la concentració relativa d'algunes d'aquestes variants. En aquest cas, és de màxima importància quines variants són detectades, ja que això constitueix la base d'aquest mètode d'antidopatge de GH. Aquí, s'estudia la rellevància d'algunes variants de GH, incloent-hi la seva generació, caracterització, anàlisi via anticossos específics i la seva detecció en mostres biològiques.
7
Pappa, Evdokia. "Sports spectacle, media and doping : the representations of Olympic drug cases in Athens 2004 and Beijing 2008." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/7477.
Full textAbstract:
This thesis explores the depiction of doping in the press. My interest in the topic stemmed from an early personal experience in competitive athletics where I was exposed to an in-sports reality that tolerated the use of performance-enhancing substances. However, references to doping in the media appeared to depict it in a different way. In order to investigate the divergence, the thesis analysed the reporting of two Olympic Games, namely Athens 2004 and Beijing 2008. It focused on empirical data and thus all articles that referenced doping were collected one month prior, during and one month after the two Olympic Games. In total 1274 articles were collected and analysed. Adopting a post-structuralist approach, the discourse analysis of the data leads to the identification of journalistic techniques that constructed discursive statements of doping. It was observed that first of all, in the case of highly publicised drug cases, these statements could be understood as constructing a moral panic episode. Secondly, the same discursive statements were circulated in the press even in the absence of positive doping samples. The thesis draws on the theories of moral regulation and governmentality to make sense of the constant presence of doping discursive statements in the press. It argues that inducting doping into sport spectacle makes its depiction seem apolitical and disconnected from society. However, in-depth theorisation of the phenomenon shows that its mediated construction plays an active role in influencing public policy.
8
Ye, Jianting. "Fabrication analysis and lithium doping in 4 Å carbon nanotubes in the channels of AlPO4̳-5 crystal /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202002%20YE.
Full textAbstract:
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.On t.p. "4̳" is subscript. Includes bibliographical references (leaves 84-86). Also available in electronic version. Access restricted to campus users.
9
Anielski, Patricia. "Langzeitnachweis anaboler Steroidhormone." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1198868584143-77693.
Full textAbstract:
Die missbräuchliche Anwendung von anabolen Substanzen erfolgt mit dem Ziel eines verstärkten Muskelaufbaus - im Sport zur Leistungsverbesserung, in der Tierzucht zum Erreichen von Zuchtidealen oder bei der Masttierhaltung zur Produktivitätssteigerung. Bisher wurden Doping- oder Medikationskontrollen zum Nachweis von anabolen Steroidhormonen üblicherweise im Urin bzw. im Blut durchgeführt. Für bestimmte Fragestellungen kann der analysierbare Zeitraum allerdings unzureichend sein oder aber die Untersuchungsmaterialien sind unter praktischen Gegebenheiten nur eingeschränkt verfügbar. Das Sammeln von Urinproben ist beispielsweise bei Zuchthengsten nur mit einem unverhältnismäßig hohen Aufwand realisierbar. Haare stellen in solchen Situationen eine Alternative dar, da sich das Entnahmeverfahren unkompliziert gestaltet und bei einer entsprechenden Haarlänge die eingelagerten Fremdstoffe länger als in Urin- oder Blutproben detektierbar sein sollten. In der vorliegenden Arbeit wurde ein effektiver Langzeitnachweis für insgesamt 11 anabole Substanzen in Pferdehaar-Proben mittels GC-HRMS und GC-MS/MS entwickelt (Nachweisgrenzen zwischen 0,1 und 5,0 pg/mg). Dabei können zum einen körperfremde anabole Wirkstoffe (z. B. Steroidester in Depotpräparaten) und zum anderen körper-eigene Steroide analysiert werden (z. B. Testosteron und Nandrolon beim Hengst). In verschiedenen Applikationsversuchen wurde gezeigt, dass durch eine Haaranalyse der Nachweis bis zu einem Jahr möglich ist. Für die endogene Nandrolonmenge in Schweifproben von unbehandelten Hengsten wurde eine signifikante Altersabhängigkeit festgestellt. Die ermittelten physiologischen Höchstkonzentrationen für Nandrolon betragen zwischen 1,1 pg/mg bei Junghengsten (1-3 Jahre) und 3,1 pg/mg bei Althengsten (11-20 Jahre). Die Bestimmung von Nandrolon in Haarproben erwies sich für die Körungskontrollen bei Junghengsten als ein geeignetes Verfahren zur Detektion einer exogenen Zufuhr. Die Untersuchung von Haaren ist zum Langzeitnachweis als Alternative gegenüber Blut- und Urinanalysen vorzuziehen, auch wenn sich retrospektiv nicht alle Fragen zum Behandlungsablauf präzise klären lassen (z. B. Angaben zur Dosierung oder zum genauen Applikationszeitpunkt). Das neu etablierte Verfahren ist außerdem die Methode der Wahl, wenn die Verfügbarkeit der übrigen Probematerialien eingeschränkt bzw. eine einfache und schnelle Beprobung erforderlich ist. Es wird bereits zur Medikationskontrolle bei Zuchthengsten sowie bei speziellen forensischen Untersuchungen eingesetzt.
10
Krishnan, Bharat. "DEVELOPMENT OF SIMULATION FRAMEWORK FOR THE ANALYSIS OF NON-IDEAL EFFECTS IN DOPING PROFILE MEASUREMENT USING CAPACITANCE ? VOLTAGE TECHNIQUE." MSSTATE, 2005. http://sun.library.msstate.edu/ETD-db/theses/available/etd-04082005-092339/.
Full textAbstract:
Silicon Carbide devices are proving to be most promising for high power and high-temperature application in recent times. Efficient and accurate characterization of the device characteristics is key to the fabrication of high quality devices and reproduction of the quality of the devices fabricated. Capacitance-Voltage profiling is one of the most commonly used techniques to measure the doping profiles of semiconductors. However, interpretation of C-V profiling in the presence of traps in the material becomes complicated. Various complications arising from compensation between donors and acceptors, partial ionization of dopants and presence of deep level impurities could yield anomalous measured profile. Silicon Carbide being a wide bandgap semiconductor, many impurities commonly found such as Boron and Aluminum are not completely ionized at Room temperature. This leads to complications in calculating doping profiles when the trap levels are deeper. Other complications arising due to series resistance effect and diode edge effect may also affect the measured profile. Accounting for these complications may be difficult by mere observation of the measured profile. Simulation can be an excellent tool to extract parameters of interest from experimental results that are influenced by non-ideal effects. Fitting of the experimentally obtained data with simulated profile using specific models may be a useful technique to quantitatively account for the deviations from the actual profiles.
11
Berndtson, Emma. "Qualitative analysis of LGD-4033 and its metabolites in equine plasma using UHPLC-MS(MS) for doping control purposes." Thesis, Uppsala universitet, Analytisk kemi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-327256.
Full textAbstract:
A new class of drugs has been developed for treatment of muscle and bone mass wasting diseases called non-steroidal selective androgen receptor modulators (SARMs). Because of their positive androgenic effects such as muscle gain, they are desirable as performance enhancers. One of those substances is LGD-4033 (4-[(2R)-2-[(1R)-2,2,2-trifluoro-1-hydroxyethyl]pyrrolidin-1-yl]-2-(trifluoromethyl)- benzonitrile). It has been detected in human samples in routine doping control and another SARM has been detected in an equine blood sample in routine doping control. It is therefore indicated that SARMs need to be screened for in routine testing in equestrian sport. The aim of this project was to identify what metabolites were found in equine plasma after an intra venous administration of LGD-4033 using UHPLC coupled with QToF-MS and determine whether the parent compound or any of its metabolites were most suitable for doping control. With the sample preparation method protein precipitation, six possible metabolites were identified in samples from three horses. Two of the metabolites were identified as phase I-metabolites (monohydroxylated and dihydroxylated). Four of the metabolites were identified as phase II-metabolites, where glucuronidation had occurred. The most suitable species for doping control were determined based on a semi- quantification and were M1a, M2 and M3a.
12
Hiramatsu, Hidenori, Kazushige Ueda, Hiromichi Ohta, Masahiro Hirano, Maiko Kikuchi, Hiroshi Yanagi, Toshio Kamiya, and Hideo Hosono. "Heavy hole doping of epitaxial thin films of a wide gap p-type semiconductor, LaCuOSe, and analysis of the effective mass." American Institite of Physics, 2007. http://hdl.handle.net/2237/11981.
Full text
13
Wang, Fagen. "Hydrogen production from steam reforming of ethanol over an Ir/ceria-based catalyst : catalyst ageing analysis and performance improvement upon ceria doping." Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00967128.
Full textAbstract:
The objective of the thesis was to analyze the ageing processes and the modifications of an Ir/CeO2catalyst for steam reforming of ethanol. Over a model Ir/CeO2 catalyst, the initial and fast deactivationwas ascribed to ceria surface restructuring and the build-up of intermediates monolayer (acetate,carbonate and hydroxyl groups). In parallel, a progressive and slow deactivation was found to come fromthe structural changes at the ceria/Ir interface linked to Ir sintering and ceria restructuring. Theencapsulating carbon, coming from C2 intermediates polymerization, did not seem too detrimental to theactivity in the investigated operating conditions. By doping ceria with PrOx, the oxygen storage capacityand thermal stability were greatly promoted, resulting in the enhanced activity and stability. The Ir/CeO2catalyst was then modified by changing the shape of ceria. It was found that the shape and therefore thestructure of ceria influenced the activity and stability significantly. A simplified modeling of theseprocesses has contributed to support the new proposals of this work.
14
Marcos, del Águila Josep. "Detecció del consum d'agents anabolitzants en humans: estratègies alternatives de preparació de mostres i anàlisi instrumental." Doctoral thesis, Universitat Pompeu Fabra, 2004. http://hdl.handle.net/10803/22692.
Full textAbstract:
Los agentes anabolizantes prohibidos por la Comisión Médica del Comité
Olímpico Internacional (COI) deben estar ausentes en las muestras de orina
objeto de análisis. El límite de detección está condicionado por la sensibilidad
del instrumento y la relación señal/ruido debida al material biológico
coextraído junto con los analitos de interés. Las nuevas exigencias de
sensibilidad del COI como la detección de nuevas sustancias utilizadas
en dosis sensiblemente inferiores, obliga al replanteamiento de la estrategia
analítica utilizada.
El objetivo general de esta tesis es: desarrollar nuevas técnicas analíticas
de alta sensibilidad para la detección de esteroides y otros anabolizantes
en orina humana mediante:
1.- Estudio de la cromatografía liquida capilar para la cuantificación
de las concentraciones de testosterona y epitestosterona en orina humana.
2.- Estudio de la purificación de la muestra previa al análisis instrumental.
- Estudio del uso de la cormatografía de inmunoafinidad (IAC) en la purificación
selectiva dela muestra.
- Desarrollo de procedimientos mediante cromatografía líquida de alta resolución
para la purificación de fracciones en los análisis de confirmación.
3.- Incremento de la sensibilidad en el análisis instrumental.
- Estudio de la formación de tert-butildimetilsilil derivados como alternativa
a los trimestilsilil derivados habitualmente utilizados.
- Estudio de la utilización de nueva instrumentación basada en la espectrometría
de masas de trampa de iones y en tándem (MS/MS) para alcanzar la sensibilidad
y selectividad requerida por los nuevos estánderes impuestos por las organizaciones
internacionales del área de la salud, en particular en el deporte.
15
Yamamoto, Mayumi Ya-Ya. "The influence of non-domestic factors on elite sport development and anti-doping policy : the cases of Japan and the UK/England." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/15137.
Full textAbstract:
The aim of this thesis is to examine the extent to which selected aspects of sport policy in Japan and also UK/England are influenced by international forces. The objectives which underpin the research aim are to analyse the characteristics of the domestic policy areas and identify the varying degree of impact of external influences on domestic sport policy. The thesis examines the interactions between domestic and international factors that shape elite sport policy and anti-doping policy and seeks to identify how domestic institutional values and ideas have been shaped by global influences. Importantly, by analysing the nature and mechanisms of global influence that are manifest at the domestic level, it is intended to identify varying degree of impact external to national policy. To achieve the above objectives, a qualitative methodology and related documentary research methods are adopted in the empirical investigations. Policy document analysis and semi-structured interviews are employed. The cases of UK (or England where appropriate) are introduced in order to generate a deeper understanding of the development of Japanese elite sport and anti-doping policy. The thesis draws on a range of theoretical frameworks, including international relations theory, international regime theory and globalisation, to analyse the empirical data. By adopting these theoretical frameworks, it is aimed to identify the possible characteristics of international policy regimes in the policy areas of elite sport and anti-doping.
16
Eberle, Alexander Richard [Verfasser], and Wolfgang [Akademischer Betreuer] Schmahl. "Growing low-dimensional supramolecular crystals via Organic Solid-Solid Wetting Deposition : physico-chemical basis, structure analysis, and doping of graphene / Alexander Richard Eberle ; Betreuer: Wolfgang Schmahl." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/119342321X/34.
Full text
17
Gómez, Castellà Cristina 1985. "Improving detection capabilities of doping agents by identification of new phase I and phase II metabolites by LC-MS/MS." Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/132539.
Full textAbstract:
Metabolic studies of doping agents have been traditionally performed by using gas chromatography coupled to mass spectrometry (GC-MS). In the last years, liquid chromatography coupled to mass spectrometry (LC-MS) has demonstrated to offer new possibilities to perform metabolic studies. The objective of this thesis was to study the metabolism (phase I and phase II) of different doping agents by LC-MS/MS in order to improve the detection capabilities of the studied substances.
For mesocarb, a thermolabile compound, the parent drug 19 metabolites were detected in urine including mono-, di- and tri-hydroxylated metabolites excreted free or conjugated with glucuronic acid and sulphate. For toremifene, an anti-estrogenic drug with poor electron ionization properties, the parent drug and 20 metabolites were detected in urine. The structure of most of the metabolites was proposed.
Anabolic androgenic steroids (AAS) metabolites conjugated with sulphate were investigated to improve the retrospectivity of the detection of these compounds. A study of hydrolysis and MS/MS behaviour of sulphate metabolites of AAS was performed, and sulphate conjugated metabolites of boldenone, methyltestosterone and metandienone were studied. Boldenone sulphate and epiboldenone sulphate were identified as boldenone metabolites in humans. They can be used as markers of exogenous boldenone administration. For methyltestosterone, three new sulphate metabolites were detected and structures were proposed. One of them, 17β-methyl-5α-androstan-3α,17α-diol 3α-sulphate was detected in urine up to 21 days after methyltestosterone administration, improving three times the retrospectivity of the detection with respect to other previously reported long-term metabolites. Several new sulphate metabolites were detected after metandienone administration. One of them was characterized as 18-nor-17β-hydroxymethyl-17α-methylandrost-1,4,13-triene-3-one conjugated with sulphate, and it was detected up to 26 days after administration, improving the retrospectivity of the detection with respect to other long-term metabolites described.
The usefulness of LC-MS/MS for the detection and characterization of metabolites of doping agents has been demonstrated, especially for the study of new phase II metabolites and for metabolic studies of compounds where GC-MS shows relevant limitations.Els estudis metabòlics de substàncies dopants han estat tradicionalment realitzats mitjançant l’ús de cromatografia de gasos acoblada a espectrometria de masses (GC-MS). En els últims anys, s’ha demostrat la utilitat de la cromatografia líquida acoblada a espectrometria de masses (LC-MS) per realitzar estudis de metabolisme. L’objectiu d’aquesta tesi va ser estudiar el metabolisme (fase I i fase II) de diferents substàncies dopants mitjançant LC-MS/MS per tal de millorar la capacitat de detecció dels compostos estudiats. Per a mesocarb, compost termolàbil, es van detectar en orina el compost inalterat i 19 metabòlits incloent metabòlits mono-, di- i tri-hidroxilats excretats lliures o conjugats amb àcid glucurònic i sulfat. Per a toremifè, un fàrmac anti-estrogènic amb espectre de masses d’impacte electrònic amb pocs ions diganòstic, es van detectar el compost inalterat i 20 metabòlits en orina. Es va proposar l’estructura de la major part de metabòlits detectats. Per tal de millorar la retrospectivitat de la detecció dels esteroides anabolitzants androgènics (AAS) es van estudiar els metabòlits conjugats amb sulfat. Es va realitzar un estudi de la hidròlisi i del comportament espectromètric dels metabòlits conjugats amb sulfat dels AAS. Es van estudiar els metabòlits conjugats amb sulfat de boldenona, metiltestosterona i metandienona. Es van identificar boldenona sulfat i epiboldenona sulfat com a metabòlits de boldenona en humans. Aquests metabòlits poden ser usats com a marcadors de l’administració exògena de boldenona. Per a metiltestosterona, es van detectar i proposar les estructures de tres nous metabòlits conjugats amb sulfat. Un d’ells, el 17β-metil-5α-androstà-3α,17α-diol 3α-sulfat, va ser detectat en orina fins a 21 dies després de l’administració de metiltestosterona. Es van detectar diversos metabòlits de metandienona conjugats amb sulfat no descrits prèviament. Un d’ells, identificat com a 18-nor-17β-hidroximetil-17α-metilandrost-1,4,13-trien-3-ona conjugat amb sulfat, va ser detectat fins 26 dies després de l’administració. Tant per a metiltestosterone com per a metandienone, els metabòlits conjugats amb sulfat permeten millorar la retrospectivitat de la detecció respecte a altres marcadors descrits anteriorment. S’ha demostrat la utilitat del LC-MS/MS per a la detecció i caracterització de metabòlits de substàncies dopants, especialment per a l’estudi de nous metabòlits de fase II i per a estudis de metabolisme de compostos que mostren limitacions en GC-MS.
18
Zhao, Wei. "Neutron Transmutation and Hydrogenation Study of Hg₁₋xCdxTe." Thesis, University of North Texas, 2007. https://digital.library.unt.edu/ark:/67531/metadc9126/.
Full textAbstract:
Anomalous Hall behavior of HgCdTe refers to a "double cross-over" feature of the Hall coefficient in p-type material, or a peak in the Hall mobility or Hall coefficient in n-type material. A magnetoconductivity tensor approach was utilized to identify presence of two electrons contributing to the conduction as well as transport properties of each electron in the material. The two electron model for the mobility shows that the anomalous Hall behavior results from the competition of two electrons, one in the energy gap graded region near the CdZnTe/HgCdTe interface with large band gap and the other in the bulk of the LPE film with narrow band gap. Hg0.78Cd0.22Te samples grown by LPE on CdZnTe(111B)-oriented substrates were exposed to various doses of thermal neutrons (~1.7 x 1016 - 1.25 x 1017 /cm2) and subsequently annealed at ~220oC for ~24h in Hg saturated vapor to recover damage and reduce the presence of Hg vacancies. Extensive Magnetotransport measurements were performed on these samples. SIMS profile for impurities produced by neutron irradiation was also obtained. The purpose for this study is to investigate the influence of neutron irradiation on this material as a basis for further study on HgCdTe74Se. The result shows that total mobility is observed to decrease with increased neutron dose and can be fitted by including a mobility inverse proportional to neutron dose. Electron introduction rate of thermal neutron is much smaller than that of fission neutrons. Total recovering of the material is suggested to have longer time annealing. Using Kane's model, we also fitted carrier concentration change at low temperature by introducing a donor level with activation energy changing with temperature. Results on Se diffusion in liquid phase epitaxy (LPE) grown HgCdTe epilayers is reported. The LPE Hg0.78Cd0.22Te samples were implanted with Se of 2.0×1014/cm2 at 100keV and annealed at 350-450oC in mercury saturated vapor. Secondary ions mass spectrometry (SIMS) profiles were obtained for each sample. From a Gaussian fit we find that the Se diffusion coefficient DSe is about one to two orders of magnitude smaller than that of arsenic. The as-implanted Se distribution is taken into account in case of small diffusion length in Gaussian fitting. Assuming a Te vacancy based mechanism, the Arrhenius relationship yields an activation energy 1.84eV. Dislocations introduced in HgCdTe materials result in two energy levels, where one is a donor and one is an acceptor. Hydrogenation treatment can effectively neutralize these dislocation defect levels. Both experimental results and theoretical calculation show that the mobility due to dislocation scattering remains constant in the low temperature range (<77K), and increases with temperature between 77K and 150K. Dislocation scattering has little effect on electrical transport properties of HgCdTe with an EPD lower than 107/cm2. Dislocations may have little effect on carrier concentration for semiconductor material with zinc blende structure due to self compensation.
19
Ramamurti, Rahul. "Synthesis of Diamond Thin Films for Applications in High Temperature Electronics." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1145630189.
Full text
20
Rutecki, Jared W. "Enhancing the Agenda: A Content Analysis of Weekly Magazine Coverage of Performance-Enhancing Drug Use in Competitive Athletics, 1986-2006." Ohio : Ohio University, 2009. http://www.ohiolink.edu/etd/view.cgi?ohiou1241446015.
Full text
21
Rewinkel, Scott Everett. "The effects of SiO₂, ZnO, and MgO doping on the mechanical and biological properties of beta-tricalcium phosphate bioceramics for bone tissue engineering, in vitro and in vivo analysis." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/s_rewinkel_100909.pdf.
Full textAbstract:
Thesis (M.S. in mechanical engineering)--Washington State University, December 2009.Title from PDF title page (viewed on Jan. 22, 2010). "School of Mechanical and Materials Engineering." Includes bibliographical references (p. 123-128).
22
Wolf, Sylvi. "Konstruktion und Charakterisierung von Reportergenassays in S. cerevisiae und S. pombe zum Nachweis anaboler androgener Substanzen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-89238.
Full textAbstract:
Der Missbrauch anaboler Substanzen zur Leistungssteigerung wird von den meisten Sportverbänden, dem Olympischen Komitee und vor allem der Welt Anti Doping Agentur (WADA) abgelehnt und sanktioniert. Trotzdessen bleibt der Missbrauch derartiger Substanzen sowohl im Leistungs- als auch im Freizeitsport nicht zuletzt aufgrund der starken Nebenwirkungen ein schwerwiegendes Problem. Allein im Leistungssport sind 2009 ca. 2 % der von der WADA durchgeführten Dopingkontrollen positiv ausgefallen. Dabei konnten in 65 % der positiv-getesteten Proben muskelaufbauende anabole Substanzen nachgewiesen werden. Im Freizeitsport konzentriert sich der Missbrauch dieser verbotenen Substanzen vor allem im Bereich des Bodybuildings.
Die einzige rechtlich relevante und routinemäßig genutzte analytische Methode für den Nachweis anaboler Steroide in Urinproben von Sportlern ist die Gas- oder Flüssigkeitschromatographie in Kombination mit der Massenspektrometrie. Diese Methoden sind jedoch sehr kosten- und zeitintensiv. Außerdem können dabei unbekannte Substanzen nur schwer nachgewiesen werden. Ein alternativer Ansatz zum Nachweis androgener anaboler Steroide führt über deren biologische Aktivität. Auf diesem Prinzip beruhen unter anderem Hefeassays. Diese Assays sind kostengünstig, schnell und einfach durchzuführen.
In dieser Arbeit wurden zwei neue Hefeassays zum einen in der Hefe Saccharomyces (S.) cerevisiae und zum anderen in der Hefe Schizosaccharomyces (S.) pombe konstruiert und hinsichtlich ihrer Eignung zur Doping-Prescreening Analyse getestet. Diese zwei Hefen wurden genutzt, da sie phylogenetisch sehr weit voneinander entfernt sind und dadurch unter anderem einen unterschiedlichen Metabolismus und einen unterschiedlichen Aufbau der Zellwand besitzen. In Hefeassays können falsch negative und falsch positive Ergebnisse auftreten, da endokrin-wirksame Substanzen in der Hefe und im humanen Organismus eine unterschiedliche Wirkung besitzen können. Humane Zellen unterscheiden sich von Hefezellen unter anderem im Metabolismus von aufgenommenen Substanzen, in der Durchlässigkeit der Zellwand für verschiedene Stoffe und in Transportsystemen, die Substanzen aus der Zelle ausschleusen. Eine Kombination dieser beiden neu konstruierten Assays verspricht den Aktivitätsnachweis eines viel größeren Substanzspektrums, als es mit einem System allein möglich wäre, wodurch eine Reduzierung falsch negativer Ergebnisse erreicht werden kann.
Als erster Schritt in dieser Arbeit wurde ein bestehendes Hefesystem von Sohoni und Sumpter (1998) charakterisiert. Der Hefestamm dieses S. cerevisiae Reportergen-Assays exprimiert den humanen Androgenrezeptor (AR) konstitutiv, da das AR Gen durch genetische Manipulation ins Genom der Hefe stabil integriert wurde. Außerdem liegt in der Hefezelle ein so genanntes Reporterplasmid vor. Dieses Plasmid trägt das lacZ Gen, welches in diesem Fall als Reportergen funktioniert und unter der Kontrolle eines androgen-sensitiven Promoters steht. Gelangen nun Androgene in diese Zellen wird das lacZ Gen abgelesen und die beta-Galactosidase gebildet. Dieses Enzym wird ins Hefemedium sekretiert und wandelt dort einen gelben in einen roten Farbstoff um. Dieser Farbumschlag kann nunmehr quantitativ gemessen und als Maß androgener Aktivität ausgewertet werden.
Die Eignung dieses Reportergenassays als Doping-Prescreening Test konnte in vielfältigen Experimenten bestätigt werden. Zunächst konnten mit diesem Assay bekannte Dopingsubstanzen und deren Metabolite anhand ihrer biologischen Aktivität nachgewiesen werden. Außerdem konnte die Spezifität des Assays gegenüber Androgenen gezeigt werden, wobei Steroide anderer Klassen, wie das Mineralocorticoid Aldosteron, das künstliche Glucocorticoid Dexamethason, das Östrogen 17beta-Östradiol und das Gestagen Progesteron und außerdem das Prohormon Dehydroepiandrosteron im Hefeassay geprüft worden sind. Alle diese Substanzen zeigten keinen relevanten Signalanstieg in physiologischen Konzentrationen. Weiterhin wurde die Praktikabilität des Hefeassays für die Doping-Prescreening Analyse anhand eines Trenbolox- und eines Methyltestosteron-Ausscheidungsversuchs untersucht. Es konnte gezeigt werden, dass die Hefen dieses Assays eine 20 %ige Urinkonzentration im Medium tolerieren und gleichzeitig die biologische Aktivität von oral eingenommenem Methyltestosteron und Estra-4,9-dien-3,17-dion (Präparatname: Trenbolox) bzw. deren Metabolite in Urinproben detektierbar ist. Außerdem wurden parallel Urinproben von Frauen und Männern, die keine androgen wirksamen Substanzen eingenommen haben, getestet. Diese Urinproben ohne exogene Zufuhr von anabolen Steroiden wiesen keinen bedeutenden Signalanstieg auf.
Eine Verbesserung des ursprünglichen Reportergenassays von Sohoni und Sumpter wurde durch den Austausch des Reportergens von lacZ zum optimierten grün fluoreszierenden Protein (EGFP) erreicht. Dadurch konnte eine deutliche Verringerung der Inkubationszeit von 48 auf 24 Stunden bewirkt werden.
Auch bei der Konstruktion der beiden neuen Reportergenassays in S. cerevisiae und S. pombe wurde daraufhin EGFP als Reportergen eingesetzt. Dafür wurde ein für die jeweilige Hefe spezifisches Reporterplasmid mit dem EGFP-Gen unter der Kontrolle eines androgen-sensitiven Promoters und ein spezifisches Expressionsplasmid mit dem Gen für den humanen Androgenrezeptor konstruiert und in die jeweilige Hefe eingebracht. Durch Optimierungsversuche wurde festgestellt, dass beide neu konstruierten Hefen eine identische einzusetzende Zellzahl, Inkubationszeit, Inkubationstemperatur und ein identisches Kulturvolumen besitzen. Daraus ergibt sich der Vorteil, dass beide Assays gut kombiniert werden können.
Mit Hilfe beider Hefeassays konnte die Wirkung verschiedener dopingrelevanter Substanzen detektiert werden, wobei der S. cerevisiae Assay eine geringfügig höhere Sensitivität zeigte als der S. pombe Assay und sogar als der Reportergenassay von Sohoni und Sumpter.
Zum weiteren Vergleich der Sensitivität beider Assays wurden drei Ausscheidungsversuche durchgeführt. Im ersten so genannten Trenbolox-Ausscheidungsversuch zeigte der S. pombe Assay in allen fünf Urinproben ein stärkeres Signal als die Referenzprobe. Im S. cerevisiae Assay konnten nur vier der fünf getesteten Urinproben eine höhere Signalintensität als die Referenzprobe erreichen. Dies lässt auf eine unterschiedliche Sensitivität beider Assays für die eingenommene Substanz Estra-4,9-dien-3,17-dion (Trenbolox) bzw. seiner Metabolite schließen. In einem zweiten Ausscheidungsversuch nach 1-Androsteron Einnahme konnte gezeigt werden, dass im Urin hohe Konzentrationen von ausgeschiedener Ausgangssubstanz oder deren Metabolite bis zu 30 Stunden nach Substanzeinnahme ein positives Signal in beiden Hefeassays hervorriefen. Wohingegen zu späteren Ausscheidungszeitpunkten beide Hefeassays sehr unterschiedliche Ergebnisse zeigten. Beide Hefen scheinen späte Metabolite von 1 Androsteron mit unterschiedlicher Sensitivität zu detektieren. Im dritten Ausscheidungsversuch mit der Substanz Methyltestosteron konnte ebenfalls eine sehr unterschiedliche Sensitivität beider konstruierter Hefeassays gegenüber Methyltestosteron und seiner Metabolite festgestellt werden.
Die Ergebnisse der Ausscheidungsversuche scheinen die Annahme zu bestätigen, dass eine Kombination beider Assays den Aktivitätsnachweis eines weiten Spektrums von androgenen Substanzen gewährleistet. Vor allem in der Dopinganalyse wäre dies von großem Vorteil, um bisher unbekannte Substanzen, wie neue so genannte Designer-Steroide, in Kombination mit der MS-Analytik nachzuweisen. Die Hefeassays bieten dabei die Möglichkeit zum einfachen, schnellen und kostengünstigen Doping-Prescreening. Auch der hier erstmals untersuchte direkte Einsatz von unbehandelten Urinproben in Hefeassays ist ein deutlicher Vorteil im Vergleich zu den klassischen Methoden, bei denen die Urinproben aufwendig gereinigt werden müssen.
Ein weiteres aus unseren Ergebnissen resultierendes Anwendungsgebiet für die konstruierten Hefeassays könnte der Nachweis der biologischen Aktivität von Antiandrogenen sein.
23
Fink, Douglas Rudolph. "Capacitance-Based Characterization of PIN Devices." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587463438933021.
Full text
24
Meyer, Elisabeth Uta. "Der gesellschaftliche Doping-Diskurs : Analysen zum Dopingproblem und mögliche Lösungsstrategien /." München : GRIN-Verl, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2938676&prov=M&dok_var=1&dok_ext=htm.
Full text
25
Jay, Frédéric. "Nouveaux substrats de silicium cristallin destinés aux cellules photovoltaïque à haut rendement : cas du silicium mono-like et du dopage aux donneurs thermiques liés à l’oxygène pour les cellules à hétérojonction de silicium." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI010/document.
Full textAbstract:
Ce travail de thèse a pour but de comprendre l’impact des propriétés électriques du silicium cristallin sur les performances des cellules solaires Silicium à HétéroJonction (SHJ) et de déterminer des spécifications matériaux nécessaires en termes de durée de vie des porteurs de charge et de résistivité.Dans une première partie de cette thèse, le potentiel du silicium mono-like a été évalué pour la fabrication de cellules solaires SHJ. La forte productivité de cette technique permet de réduire considérablement les coûts de fabrication des plaquettes. Des rendements de conversion de 20% équivalents à ceux des matériaux du marché ont été obtenus ainsi qu’un rendement de 21.6% avec l’utilisation d’un procédé de fabrication de cellules haut rendements. Ces valeurs ont été obtenues pour des durées de vie volumiques moyennes sur les plaquettes supérieures à 1ms. Les principaux limitations de la qualité du matériau mono-like ont été identifiés. D’abord, la présence de zones multicristallines sur certaines plaquettes rend le matériau incomptable avec le procédé SHJ notamment en ce qui concerne les étapes de texturation des surfaces et ensuite l’uniformité en épaisseur des couches déposées. Ce type de défauts fait chuter en premier lieu la Jcc, puis la Vco et le FF et finalement le rendement de conversion. De plus, la présence de contamination et la génération de dislocations aux extrémités du lingot font également chuter la durée de vie volumique et les paramètres photovoltaïques des cellules. Finalement, seulement 30% de la hauteur de lingot a pu être utilisé pour des hauts rendements de conversion.La deuxième partie a été consacrée à l’étude et l’optimisation, avec la technologie SHJ, d’une technique de dopage innovante remplaçant celles utilisant des impuretés dopantes, telle que le phosphore, en générant des donneurs thermiques dans le substrat silicium cristallin. Cette méthode de dopage présente l’avantage d’utiliser l’oxygène naturellement présent dans le silicium en transformant en dopant par des recuits à 450°C. Cette technique est uniquement valable avec une procédé basse température tel que celui utilisé dans ce travail de thèse et permettrait de contrôler les propriétés électriques du silicium sur l’ensemble d’un lingot Cz afin d’augmenter le rendement matière. La compatibilité du silicium cristallin dopé par des DT a été validée pour une gamme de résistivité de 3-10Ω.cm et durées de vie volumique de 3-10ms. La limite d’utilisation des DT pour l’obtention de hauts rendements correspond à une concentration inférieure à 7x1014cm-3 (3Ω.cm, 3ms). La technique de dopage a été transférée avec succès à l’échelle du lingot et a permis d’obtenir de rendement de 20.7% avec un procédé industriel et même de 21.7% avec une métallisation « smart-wire ». Une perte de FF a été observée par rapport aux références, liées à une résistance série élevée dont l’origine n’a pas encore été confirmée mais dont la source la plus probable serait l’inhomogénéité radiale de résistivité générée par le dopageThis study aims to understand the electrical properties impact of the crystalline Silicon on the HeteroJunction (SHJ) solar cells performances and define the required material specifications in terms of minority carrier lifetime and bulk resistivity.In the first part of this work, the potential of the mono-like silicon was evaluated for SHJ solar cells production The high productivity of the crystallization method allows to significantly reduce the material cost. 20% efficiencies comparable to reference wafers were obtained for industrial process and had reached 21.6% values have been reached with a high efficiency process. Values above 1ms bulk lifetime were mandatory to obtain these results. The main limitations of the material properties were identified. First, the presence of multicrystalline zones on the material is incompatible with the SHJ process especially regarding the texturization step and then layers thickness’ uniformity. This defects drive down, at the first order, the Jsc and then the Voc and FF. Moreover, the metallic contamination and the dislocations generation at the ingots ends induce also a bulk lifetime degradation and PV performances drop. Finally, only 30% of the ingot height was usable to obtain high solar cell efficiencies.In the second part of this work, an innovative doping method, replacing the ones which use doping impurities, such as phosphorus, by generating thermal donors (TD) was studied. The advantages of this doping method are to use the oxygen naturally content in the silicon to generate the doping after 450°C annealing. This method is only possible if low temperature solar cell process is performed such the one used in this work. It could control the electrical properties of the crystalline silicon throughout a complete Cz ingot and increase the material yield. For a resistivity range of 3-10Ω.cm and bulk lifetime between 3 and 10ms, the TD doped material is compatible with SHJ technology. The maximum TD concentration for a SHJ application was estimated to 7x1014cm-3.The doping method was successfully transferred to the ingot scale and allowed reaching 20.7% efficiency with an industrial process and 21.7% with the “smart-wire” improved metallization. A FF loss was observed compared to the references, related to high series resistances. The origin has not been confirmed yet, but the most likely source would be the radial resistivity inhomogeneity generated by doping on silicon bulk
26
Amponsah, Sylvester. "Optical Characterization of Nitrogen-vacancy Centers andResonance Analysis of CVD Grown Diamond MEMS Devices." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1528479091207253.
Full text
27
Pirnat, Jochen. "Doping im Hochleistungssport : eine ökonomische Analyse /." Saarbrücken : VDM Verl. Müller, 2008. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016725300&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
Full text
28
Meyer, Elisabeth Uta. "Der gesellschaftliche Doping-Diskurs Analysen zum Dopingproblem und mögliche Lösungsstrategien." München GRIN-Verl, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?id=2938676&prov=M&dok_var=1&dok_ext=htm.
Full text
29
Velayudhan, Nirmalkumar. "Analysis of Thermally Diffused Single Mode Optical Fiber Couplers." Thesis, Virginia Tech, 1994. http://hdl.handle.net/10919/36771.
Full textAbstract:
The phenomenon of dopant diffusion as a viable means of coupler fabrication is
investigated. It is well known that the diffusion of dopants can improve the uniformity of
multimode star couplers manufactured by the fused biconical taper technique. The
theoretical basis for the same phenomenon in a single mode coupler is developed, on the
basis of the theory of diffusion and the Gaussian approximation for circular fibers.
A novel technique to manufacture and design single mode optical fiber couplers
with a minimization of the manufacturing complexity is demonstrated. Traditionally fused
biconical tapered couplers have been manufactured by twisting, fusing and elongating
optical fibers at elevated temperatures. Usually, high temperature oxy-hydrogen flames are
used for such purposes and some degree of skill is needed for a human operator. The
complexity of control procedures for automation of the process is greatly increased by the
fact that the tapering process is an integral part of the feedback loop. This can be eliminated
if a constant tension is maintained on the fibers in the heating process while heat is applied
uniformly from a source such as a platinum wire furnace. Since the refractive index
differentials responsible for the guiding phenomenon at optical frequencies are directly
dependent on concentration of dopants like fluorine and germania, radial diffusion of such
dopants causes the fiber cores that are heated in a platinum wire furnace to come closer
together. Such proximity leads to the phenomenon of evanescent field interaction or
coupling of optical power from one arm of the coupler to the other.
The time evolution of the coupling process can be predicted in theory. While initial
results are promising, the ability to automate the manufacture of couplers will be
successful only after greater control over the variables is established. It is the intention of
this work to understand the physics behind the mechanism as well as to prove the
feasibility of modeling real world phenomena under controlled conditions.Master of Science
30
Janák, Marcel. "Diagnostika polovodičů a monitorování chemických reakcí metodou SIMS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443241.
Full textAbstract:
Hmotnostná spektrometria sekundárnych iónov s analýzou doby letu (TOF-SIMS) patrí vďaka vysokej citlivosti na prvkové zloženie medzi významné metódy analýzy pevných povrchov. Táto práca demonštruje možnosti TOF-SIMS v troch odlišných oblastiach výskumu. Prvá časť práce sa zaoberá lokalizáciou defektov vysokonapäťových polovodičových súčiastok, ktorá je nevyhnutná k ich ďalšiemu skúmaniu metódou TOF-SIMS. Bola navrhnutá experimentálna zostava s riadiacim softvérom umožňujúca automatizované meranie záverného prúdu v rôznych miestach polovodičový súčiastok. Druhá časť práce sa zaoberá kvantifikáciou koncentrácie Mg dopantov v rôznych hĺbkach vzoriek AlGaN. Kvantifikácia je založená na metóde RSF a umožňuje charakterizáciu AlGaN heteroštruktúr určených na výrobu tranzistorov s vysokou elektrónovou mobilitou (HEMT) alebo na výrobu rôznych optoelektronických zariadení. Sada 12 AlGaN kalibračných vzoriek dopovaných Mg, určených na kvantifikáciu hĺbkových profilov, bola pripravená metódou iónovej implantácie. Posledná časť práce demonštruje možnosti metódy TOF-SIMS vo výskume heterogénnej katalýzy. Hlavným objektom nášho výskumu je dynamika oxidácie CO na oxid uhličitý na polykryštalickom povrchu platiny za tlakov vysokého vákua. V tejto práci prezentujem prvé TOF-SIMS pozorovanie časopriestorových vzorov v reálnom čase, ktoré vznikajú v dôsledku rôzneho pokrytia povrchu Pt reaktantmi. Výsledky TOF-SIMS experimentu boli porovnané s výsledkami podobného experiment v rastrovacom elektrónovom mikroskope (SEM).
31
Gersdorf, Ingrid. "Spectroscopic analysis of erbium-doped silicon and ytterbium-doped indium phosphide." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2001. http://dare.uva.nl/document/60743.
Full text
32
Kurdi, Mohamad. "Sur l'utilisation des sulfures en catalyse d'hydrotraitement le trisulfure du niobium /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376148133.
Full text
33
Waidmann, Stephan. "Elektronische Eigenschaften von Diamant und diamantartigen Kohlenstoffen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2001. http://nbn-resolving.de/urn:nbn:de:swb:14-997953406187-81897.
Full textAbstract:
Im Hinblick auf das immense Potential von Diamant als Material für die Mikroelektronik wurden im Rahmen dieser Arbeit undotierte und dotierte Diamantfilme mittels chemischer Gasphasenabscheidung auf Silizium präpariert und anschließend auf ihre elektronischen Eigenschaften hin untersucht. Für Letzteres wurde hauptsächlich die Elektronen-Energieverlustspektroskopie in Transmission verwendet. In situ Gasphasendotierung oder Ionenimplantation wurde zur Dotierung der Filme mit Bor, Lithium oder Phosphor eingesetzt. Bei der Ionenimplantation wurde aufgrund der Erzeugung von Strahlenschäden generell eine Erhöhung des sp2-Anteils beobachtet: Letzterer konnte jedoch im Falle der Bordotierung durch eine, den Implantationsprozeß folgende, Hochtemperaturtemperung wieder deutlich vermindert werden. Für die in situ Dotierung mit Bor wurde eine Verringerung des sp2-Gehaltes mit steigender Dotierkonzentration gefunden. Für den Film mit der höchsten Borkonzentration konnte auch die B1s Absorptionskante untersucht werden. Sie gibt Hinweise auf den überwiegenden Einbau der Boratome in einer tetragonalen Orientierung. Das hiermit verbundene Vorhandensein von Akzeptoren führt zu elektronischen Anregungen im Energiebereich der Bandlücke, welche mittels Infrarotspektroskopie und EELS nachgewiesen werden konnten. Aus den EELS Messungen lassen sich Akzeptorkonzentrationen berechnen, welche wiederum den hohen Anteil an tetraedrisch eingebauten Boratomen bestätigen. Desweiteren untersucht wurden, als interessante Materialklasse mit weitreichendem technologischem Potential, undotierte und stickstoffdotierte, diamantartige amorphe Kohlenstoffilme und hierbei insbesondere die Abhängigkeit der elektronischen und optischen Eigenschaften von der Ionenenergie und dem Stickstoffpartialdruck während der Filmpräparation. Die Plasmonenergien, Massendichten, sp3-Anteile und die optischen Bandlücken der Filme wurden quantitativ bestimmt, wobei das jeweilige Maximum bei einer Ionenenergie von 100 eV gefunden wurde. Alle eben genannten Größen verringern sich kontinuierlich mit zunehmendem Stickstoffanteil. Eine Kramers-Kronig Analyse der Verlustspektren gibt Zugriff auf den Real- und Imaginärteil der dielektrischen Funktion und damit auf das Spektrum der Einteilchenanregungen. Die Hybridisierung der Kohlenstoff- und der Stickstoffatome wurde detailliert aus den jeweiligen 1s Absorptionskanten bestimmt. Weiterhin wurde Diamant als Modellsystem eines Festkörpers mit rein kovalenten Bindungen untersucht, insbesondere die Verlustfunktion von Diamant entlang mehrerer Hochsymmetriekristallrichtungen über einen großen Energie- und Impulsbereich. Aus den EELS Messungen erschließt sich unmittelbar die stark anisotrope Plasmonendispersion von Diamant. Aus dem Vergleich der experimentellen Spektren mit ab initio LDA Rechnungen, die sowohl Kristallokalfeldeffekte als auch Austausch- und Korrelationseffekte beinhalten, lassen sich direkt Rückschlüsse auf den Einfluß der verschiedenen Effekte ziehen. Schon im optischen Limit, aber umso mehr mit steigendem Impulsübertrag q, wird eine Überlagerung der kollektiven Plasmonanregung mit Einteilchenanregungen im Energiebereich des Plasmons beobachtet, woraus eine Kopplung zwischen beiden Arten von Anregungen resultiert. Abgesehen vom deutlichen Einfluß der Bandstruktur auf die Plasmonendispersion läßt die überaus inhomogene Elektronenverteilung von Diamant auf nicht zuvernachlässigende Kristallokalfeldeffekte schließen. Der Vergleich zwischen experimentellen und berechneten Spektren zeigt deutlich, wie die Kristallokalfeldeffekte in der Tat mit steigendem Impulsübertrag an Gewicht zunehmen und die Struktur der Verlustfunktion mitbestimmenIn the context of the immense potential of diamond as a material for use in the microelectronics industry, in this thesis pristine and doped diamond films have been deposited on silicon using chemical vapour deposition. Subsequently their electronic properties have been investigated using mainly electron energy-loss spectroscopy. Doping of the films with boron, lithium or phosphorous was carried out either via in-situ gas phase doping during film growth or using ion implantation. Upon ion implantation an increase of the carbon content with sp2 hybridisation has generally been found due to ion beam induced damage. In the case of boron doping it was possible to significantly reduce this sp2-contribution using a high temperature anneal. For the in-situ doping with boron, upon increasing doping concentration a decrease of the sp2-contribution was found. For the sample with the highest boron content the boron 1s absorption edge could also be investigated, providing evidence for the preferential incorporation of the boron atoms into tetrahedrally co-ordinated sites. This boron incorporation leads to the existence of electronic excitations in the energy range of the band gap, which could be observed using both infrared and electron energy-loss spectroscopy. From the electron energy-loss measurements it was possible to calculate acceptor concentrations which were consistent with the large amount of tetrahedrally co-ordinated boron atoms. A second theme in this thesis involved the study of pristine and nitrogen doped diamond-like amorphous carbon films, which are an interesting material class with far-reaching technological potential. Here the focus of the research concerned the dependency of the electronic and optical properties of the films upon the ion energy and the nitrogen partial pressure applied during the film preparation. The plasmon energies, mass densities, sp3 contribution and the optical band gaps of the samples were determined quantitatively, whereby the maximum in all these quantities was found to occur for ion energies of 100 eV. Furthermore, all of these characteristics were found to decrease continually with increasing nitrogen content. A Kramers-Kronig analysis of the loss spectra enabled the derivation of the real and imaginary parts of the dielectric function and with this of the complete spectrum of single particle excitations. The hybridization between the carbon and nitrogen atoms was also studied in detail from the analysis of the respective 1s absorption edges. Furthermore this thesis deals with the investigation of diamond as a model system for solids with pure covalent bonds. In particular, the loss function of diamond was measured along different high symmetry directions over a wide range of energy and momentum. Firstly, the EELS measurements showed directly the strongly anisotropic nature of the plasmon dispersion in diamond. Secondly, by the comparison of the experimental spectra with ab initio LDA-based calculations that include crystal local field effects as well as exchange and correlation contributions, conclusions can be drawn as to the influence of these quantities. In the optical limit, but even more so with increasing momentum transfer q, a superposition of the collective plasmon excitation and the single particle excitations in the energy range of the plasmon is observed. This energetic proximity results in a coupling between both types of excitations. Apart from the distinct influence of the bandstructure on the plasmon dispersion, the considerably inhomogeneous electron distribution of diamond would lead one to expect significant crystal local field effects in this system. The comparison between the experimental and the calculated spectra shows explicitly that the crystal local field effects increase with increasing momentum transfer and play an important role in defining the structure of the loss function
34
Domange, Jocelyn. "Étude et exploitation de bolomètres de nouvelle génération à électrodes concentriques pour la recherche de matière noire froide non-baryonique dans l’expérience Edelweiss II." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112169/document.
Full textAbstract:
EDELWEISS est une expérience de détection directe de matière noire froide non-baryonique sous forme de particules massives et faiblement interagissantes (connues sous l'acronyme de WIMPs), qui constituent actuellement les candidats les plus populaires pour rendre compte de la masse manquante de l'Univers. Dans ce but, EDELWEISS utilise des bolomètres de germanium opérés à température cryogénique (20 mK environ) dans le Laboratoire Souterrain de Modane (LSM) à la frontière franco-italienne. En particulier, depuis 2008, un nouveau type de détecteur est en fonctionnement, équipé d'électrodes concentriques pour optimiser le rejet des évènements de surface (détecteurs à grilles coplanaires). Cette thèse se décompose en plusieurs axes de recherche. Tout d'abord, nous avons réalisé des mesures concernant la collecte des charges dans les cristaux. Les lois de vitesse des porteurs (électrons et trous) ont été déterminées dans le germanium à 20 mK dans la direction <100>, et une étude complète de la répartition des charges a été menée, avec une évaluation de l'anisotropie du transport et de la diffusion transverse des porteurs. Ces résultats permettent d'avoir une meilleure compréhension du fonctionnement interne des détecteurs d'Edelweiss. Ensuite, des études portant sur l'amélioration des performances ont été effectuées. Nous avons en particulier permis d'optimiser la procédure de régénération des cristaux et améliorer le rejet passif des évènements de surface (β). Le volume utile de détection des détecteurs a été évalué en utilisant les raies de deux radio-isotopes activés cosmiquement, le 68Ge et le 65Zn. Enfin, une étude exhaustive portant sur l'étude des spectres à basse énergie a été menée, ce qui permet de mettre au point une méthode d'analyse systématique pour la recherche de WIMPs de basse masse dans EDELWEISSEDELWEISS is a direct non-baryonic cold dark matter detection experiment in the form of weakly interacting massive particles (also known as WIMPs), which currently constitute the most popular candidates to account for the missing mass in the Universe. To this purpose, EDELWEISS uses germanium bolometers at cryogenic temperature (20 mK approximately) in the Underground Laboratory of Modane (LSM) at the French-Italian border. Since 2008, a new type of detector is operated, equipped with concentric electrodes to optimize the rejection of surface events (coplanar-grid detectors). This thesis work is divided into several research orientations. First, we carried out measurements concerning charge collection in the crystals. The velocity laws of the carriers (electrons and holes) have been determined in germanium at 20 mK in the <100> orientation, and a complete study of charge sharing has been done, including an evaluation of the transport anisotropy and of the straggling of the carriers. These results lead to a better understanding of the inner properties of the EDELWEISS detectors. Then, studies relating to the improvement of the performances were carried out. In particular, we have optimized the space-charge cancellation procedure in the crystals and improved the passive rejection of surface events (β). The fiducial volume of the detectors has been evaluated using two X-ray lines from cosmically activated radionuclides: 68Ge and 65Zn. Lastly, an exhaustive study of the low energy spectra has been carried out, which makes it possible to develop a systematic analysis method for the search of low-mass WIMPs in EDELWEISS
35
Pothin, Romain. "Synthèse, caractérisation et mise en forme de nouveaux matériaux thermoélectriques à base de ZnSb." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT231/document.
Full textAbstract:
La chaleur dégagée par des dispositifs à différentes échelles (microprocesseurs, automobiles, habitations, usines) constitue une source quasi inexploitée d’énergie. La conversion de cette énergie thermique en énergie électrique est possible via l’emploi de générateurs thermoélectriques. Cependant actuellement leur usage est peu répandu du fait de leur faible rendement, de la toxicité et du coût des matériaux. L’objectif de cette thèse qui fait suite à la thèse théorique de Kinga Niedziolka (Université Montpellier, 2014) était l’obtention de nouveau matériaux thermoélectriques performants à base de ZnSb sur la base des résultats obtenus par modélisation. Conformément aux calculs réalisés et en accord avec le partenaire industriel (Hutchinson), les dopants choisis pour ZnSb ont été l’aluminium (1% en substitution du zinc), le tellure (1% en substitution de l’antimoine, le titane (1% en substitution du zinc) et l’yttrium (1% en substitution du zinc). L’objectif ici est de synthétiser et de caractériser les matériaux qui ont été calculés de type n (conduction électrique assurée par les électrons). Les matériaux ont été synthétisés par fusion, trempe et recuit et ont été obtenus sous forme de lingot polycristallin. Ils ont été caractérisés par diffraction des rayons X, microscopie électronique à balayage et microsonde de Castaing. Leur mise en forme pour les caractérisations thermoélectriques a ensuite été mise au point. C’est en utilisant la technique du Spark Plasma Sintering (SPS) que nous avons atteint des densités très intéressantes de l’ordre de 98% pour tous les matériaux contenant un dopant. Les caractérisations thermoélectriques ont été conduites en fonction de la température jusqu’à 600 K au moyen d’un appareillage de type ZEM-3.Les travaux de dopage se sont concentrés sur les matériaux dopés au tellure présentant les résultats les plus prometteurs. Cependant les caractérisations thermoélectriques des matériaux synthétisés n’ont pas permis de mettre en évidence le passage au type n souhaité. Cependant, une avancée a été réalisée en ce qui concerne ZnSb non dopé qui est naturellement un matériau de type p (conduction électrique assurée par les trous): grâce à la mise en œuvre de la mécanosynthèse nous avons obtenu un matériau présentant de meilleurs propriétés que ceux existants. Des analyses de ce matériau au microscope électronique en transmission ainsi que des analyses par la méthode XPS ont conduit à l’identification de certains précipités responsables de l’amélioration de ses propriétés thermoélectriques. De plus, le matériau ZnSb obtenu, présente une grande stabilité en température ce qui renforce d’autant plus son intérêt d’utilisation par rapport à d’autres matériaux dans la même gamme de températureThe heat loss from different sources at different scales (microprocessors, cars, houses, factories) is an almost untapped source of energy. The conversion of this thermal energy into electrical energy is possible through the use of thermoelectric generators. However at the present time their use is not widespread due to their low efficiency, toxicity and because of the cost of the existing materials. The aim of this thesis that follows the DFT calculations previously made during Kinga Niedziolka’s thesis, (University of Montpellier, 2014) was to obtain new efficient thermoelectric materials based on ZnSb relying on the calculation results. Based on the calculations and in agreement with the industrial partner Hutchinson, aluminum (1 % at. in substitution of Zn), tellurium (1 % at. in substitution of Sb), titanium (1 % at. in substitution of Zn) and yttrium (1 % at. in substitution of Zn) were selected as dopants. The objective, was to synthesize and characterize the materials which were calculated as n type semiconductors (electron conduction). The materials were synthesized by melting, quenching and annealing. They were obtained in the form of polycrystalline ingots. They were characterized by X-ray diffraction, scanning electron microscopy and EDS and WDS microanalysis. Their shaping for thermoelectric characterization was then developed. The technique of Spark Plasma Sintering (SPS) was chosen to this aim and we achieved very interesting densities of around 98% for all doped materials. Thermoelectric characterizations were carried out up to 600 K by means of a ZEM-3 type apparatus. Only tellurium doped materials with the most promising results were thoroughly studied. However, the thermoelectric characterization of the synthesized doped materials didn’t show the expected transition to an n-type conduction. However, progress was made regarding ZnSb as a p-type material. The optimization of the mechanical alloying process led to a very promising ZnSb material. The analyses of this material by transmission electron microscopy and XPS analysis led to the identification of some precipitates which give rise to improved thermoelectric properties compared to existing p-type ZnSb. Furthermore the obtained material has a high thermal stability reinforcing its interest compared to other materials for applications in the same temperature range
36
Penlap, Woguia Lucien. "Analyses par faisceaux d'ions de structures tridimensionnelles (3D) pour des applications en nanotechnologie." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAY015/document.
Full textAbstract:
Afin d'optimiser les performances des circuits intégrés, l’industrie de la micro et nanotechnologie mène d'intenses recherches sur la miniaturisation à l'échelle sub-22nm de leurs principaux constituants que sont les transistors MOS. La réduction de la taille de grille atteint néanmoins des limites qui rendent problématique le contrôle du canal. L'une des approches les plus prometteuses pour contourner ce dilemme et ainsi poursuivre la miniaturisation des futurs nœuds technologiques, consiste au développement des transistors d’architectures 3D (Trigate ou FinFET). La mise au point de telles structures requiert une caractérisation de plus en plus fine, surtout à une étape clé de leur élaboration, qui est celle du dopage par implantation ionique. Du fait des faibles profondeurs implantées, l'analyse par diffusion d'ions de moyenne énergie (MEIS) est tout à fait adaptée pour quantifier les implants et évaluer la conformité du dopage grâce à sa bonne résolution en profondeur (0.25 nm). Néanmoins, les dimensions de la sonde (0.5 × 1 mm2) étant très supérieures à celles des motifs, il nous a fallu développer un protocole d’analyse propre à de telles architectures. Les échantillons étudiés dans le cadre de cette thèse sont des systèmes modèles. Ils sont constitués de réseaux de lignes de silicium (Si) 3D, formées par gravure lithographique par faisceaux d’électrons (e-beam) sur des plaques 300 mm de types silicium sur isolant (SOI). Le dopage a été réalisé à une énergie de 3 keV par implantions conventionnelle (ou beam line) et immersion plasma (PIII).L’analyse des spectres MEIS des implants insérés dans chaque facette des motifs a été possible grâce aux simulations 3D types Monte-Carlo effectuées avec le logiciel PowerMEIS. Nous avons ainsi développé une nouvelle méthode adaptée à la caractérisation du dopage 3D. Les mesures ont montré que, contrairement à la méthode PIII, la dose implantée par la méthode conventionnelle correspond à celle visée. Cependant la distribution des dopants introduits au sein des nanostructures par les deux méthodes de dopage n’est pas uniforme. Dans les échantillons implantés par PIII, on a observé une importante concentration des dopants aux sommets des motifs et un faible dopage des flancs. Ceci étant moins marqué dans celui implanté par la méthode conventionnelle. En corrélant les techniques de Microscopie Electronique en Transmission (MET), d’analyses par rayons x synchrotron et MEIS, nous avons également pu déterminer les dimensions des zones implantées ainsi que celles des zones cristallines dans les réseaux de lignes gravées.L'exploitation de la technique MEIS en mode canalisation a permis une évaluation complète des couches non gravées. L’investigation des endommagements post – dopage dans les régions cristallines non implantées ont été menées toujours avec la même technique MEIS. Les résultats ont révélé une importante influence de la méthode d’implantation et la température sur les défauts et les déformations dans le cristal. L’origine des anomalies au sein des échantillons a ainsi été identifiée en corrélant les mesures MEIS et celles par spectrométrie de masse des ions secondaires en temps de vol (ToF-SIMS)With the aim of optimizing the performances of integrated circuits (ICs), the nanotechnology industry is carrying out intense research activities on the miniaturization at the sub-22 nm scale of their main constituents: the MOS transistors. Nevertheless, the shrinking of the gate size has reached the limits that make the control of the channel problematic. One of the most promising approaches to circumvent this dilemma and thus further the miniaturization of the future technological nodes, is the development of transistors of 3D architecture (Trigate or FinFET). The elaboration of such nanostructures requires increasingly fine characterization tools precisely at a key stage of their fabrication, namely the ion implantation doping. Given the ultra-shallow implantation depths, the medium energy ion scattering (MEIS) analysis technique is suitable for quantifying the implants and evaluating the doping conformity thanks to its good depth resolution (0.25 nm). However, the dimensions of the beam (0.5×1 mm2) being by far larger than those of the patterns, we had to develop an analysis protocol dedicated to such architectures. The samples studied in the framework of this thesis are considered as model systems. They are constituted of 3D silicon (Si) Fin – shaped line gratings, etched on the 300 mm wafers of silicon on insulator (SOI) types by using the electron beam (e-beam) lithography. The doping has been carried out at an energy of 3 keV by using the conventional (or beam line) and plasma immersion ion implantation (PIII) methods.The analyses s of the MEIS spectra of the dopants implanted into each part of the patterns were possible thanks to the 3D Monte-Carlo simulations performed with the PowerMEIS software. We have thus developed a new method suitable for the characterization of the 3D doping. The measurements have shown that, contrarily to the PIII method, the dose implanted by the conventional method is as targeted. However, the distribution of the dopants inserted within the nanostructures by using the two doping methods is not uniform. In the PIII implanted samples, a large dopants' focusing at the tops of the patterns and low sidewalls' doping have been observed. This is less marked in the one implanted by the conventional method. By correlating the Transmission Electron Microscopy (TEM), synchrotron x – ray analyses and MEIS, we have also determined the dimensions of the implanted and crystal areas of the line gratings.The exploitation of the MEIS technique in channeling mode has permitted the full assessment of the impacts of the implantation in the non-etched layers. The investigations of the crystal qualities in the non-implanted areas were carried out with the same technique. The results show that the temperature conditions have a considerable influence on the defects and lattice deformations. The origin of the anomalies in the samples has thus been identified by correlating the MEIS and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) measurements
37
Khoury, Rasha. "Nanometer scale point contacting techniques for silicon Photovoltaic devices." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLX070/document.
Full textAbstract:
Au cours de cette thèse, j’ai étudié la possibilité et les avantages d’utiliser des contacts nanométriques au-dessous de 1 µm. Des simulations analytiques et numériques ont montré que ces contacts nanométriques sont avantageux pour les cellules en silicium cristallin comme ils peuvent entrainer une résistance ohmique négligeable. Mon travail expérimental était focalisé sur le développement de ces contacts en utilisant des nanoparticules de polystyrène comme un masque. En utilisant la technique de floating transfert pour déposer les nanosphères, une monocouche dense de nanoparticules s’est formée. Cela nécessite une gravure par plasma de O2 afin de réduire la zone de couverture des NPs. Cette gravure était faite et étudiée en utilisant la technique de plasmas matriciels distribués à résonance cyclotronique électronique (MD-ECR). Une variété de techniques de créations de trous nanométriques était développée et testée dans des structures de couches minces et silicium cristallin. Des trous nanométriques étaient formés dans la couche de passivation, de SiO2 thermique, du silicium cristallin pour former des contacts nanométriques dopés. Un dopage local de bore était fait, à travers ces trous nanométriques par diffusion thermique et implantation ionique. En faisant la diffusion, le dopage local était observé par CP-AFM en mesurant des courbes de courant-tension à l’intérieur et à l’extérieur des zones dopées et en détectant des cellules solaires nanométriques. Par contre le processus de dopage local par implantation ionique a besoin d’être améliorer afin d’obtenir un résultat similaire à celui de diffusionThe use of point contacts has made the Passivated Emitter and Rear Cell design one of the most efficient monocrystalline-silicon photovoltaic cell designs in production. The main feature of such solar cell is that the rear surface is partially contacted by periodic openings in a dielectric film that provides surface passivation. However, a trade-off between ohmic losses and surface recombination is found. Due to the technology used to locally open the contacts in the passivation layer, the distance between neighboring contacts is on the order of hundreds of microns, introducing a significant series resistance.In this work, I explore the possibility and potential advantages of using nanoscale contact openings with a pitch between 300 nm to 10 µm. Analytic and numerical simulations done during the course of this thesis have shown that such nanoscale contacts would result in negligible ohmic losses while still keeping the surface recombination velocity Seff,rear at an acceptable level, as long as the recombination velocity at the contact (Scont) is in the range from 103-105 cm/s. To achieve such contacts in a potentially cost-reducing way, my experimental work has focused on the use of polystyrene nanospheres as a sacrificial mask.The thesis is therefore divided into three sections. The first section develops and explores processes to enable the formation of such contacts using various nanosphere dispersion, thin-film deposition, and layer etching processes. The second section describes a test device using a thin-film amorphous silicon NIP diode to explore the electrical properties of the point contacts. Finally, the third section considers the application of such point contacts on crystalline silicon by exploring localized doping through the nanoholes formed.In the first section, I have explored using polystyrene nanoparticles (NPs) as a patterning mask. The first two tested NPs deposition techniques (spray-coating, spin-coating) give poorly controlled distributions of nanospheres on the surface, but with very low values of coverage. The third tested NPs deposition technique (floating transfer technique) provided a closely-packed monolayer of NPs on the surface; this process was more repeatable but necessitated an additional O2 plasma step to reduce the coverage area of the sphere. This was performed using matrix distributed electron cyclotron resonance (MD-ECR) in order to etch the NPs by performing a detailed study.The NPs have been used in two ways; by using them as a direct deposition mask or by depositing a secondary etching mask layer on top of them.In the second section of this thesis, I have tested the nanoholes as electrical point-contacts in thin-film a-Si:H devices. For low-diffusion length technologies such as thin-film silicon, the distance between contacts must be in the order of few hundred nanometers. Using spin coated 100 nm NPs of polystyrene as a sacrificial deposition mask, I could form randomly spaced contacts with an average spacing of a few hundred nanometers. A set of NIP a-Si:H solar cells, using RF-PECVD, have been deposited on the back reflector substrates formed with metallic layers covered with dielectrics having nanoholes. Their electrical characteristics were compared to the same cells done with and without a complete dielectric layer. These structures allowed me to verify that good electrical contact through the nanoholes was possible, but no enhanced performance was observed.In the third section of this thesis, I investigate the use of such nanoholes in crystalline silicon technology by the formation of passivated contacts through the nanoholes. Boron doping by both thermal diffusion and ion implantation techniques were investigated. A thermally grown oxide layer with holes was used as the doping barrier. These samples were characterized, after removing the oxide layer, by secondary electron microscopy (SEM) and conductive probe atomic force microscopy (CP-AFM)
38
Yamane, H., T. Kawano, K. Tatsumi, Y. Fujimichi, and S. Muto. "Site occupancy determination of Eu/Y doped in Ca2SnO4 phosphor by electron channeling microanalysis." Elsevier, 2011. http://hdl.handle.net/2237/20827.
Full text
39
Atmani, Hassane. "Investigations dans le domaine des comportements thermiques de matériaux désordonnés : application au sélénium et aux mélanges Se-Bi à faible concentration en bismuth." Rouen, 1988. http://www.theses.fr/1988ROUES009.
Full text
40
MOREAU, Patrick. "Diffusion Moléculaire d'un dopant hydrosoluble dans une phase lamellaire lyotrope ---- transition smectique - cholestérique dans un mélange de molécules amphiphiles." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2004. http://tel.archives-ouvertes.fr/tel-00009676.
Full textAbstract:
L'étude des propriétés de diffusion moléculaire d'un dopant dans une phase lamellaire lyotrope orientée nous permet de mettre en évidence les caractéristiques de diffusion dans un milieu fortement anisotrope. En particulier, l'effet de la dilution du système met en évidence deux régimes : un régime dilué où les molécules diffusent comme dans un solvant et un nouveau régime, très confiné, dans lequel les molécules diffusent comme des dopants membranaires. Le développement d'un modèle prenant en compte la fluidité des membranes nous permet d'interpréter ces résultats dans la majorité des cas étudiés et révèle aussi l'importance de l'anisotropie des diffuseurs. Dans la seconde partie, nous nous intéressons à l'étude du mécanisme microscopique mis en jeu dans la transition smectique – cholestérique dans les cristaux liquides lyotropes. En utilisant un système déjà connu au laboratoire (DMPC/C12E5/eau), nous validons expérimentalement le scénario de transition par débouclage de boucles de défauts proposé théoriquement depuis plusieurs années. Nous proposons ainsi un système expérimental de choix pour l'étude de ce genre de transition, prédites dans différents domaines de la physique de la matière condensée. La visualisation directe des défauts, la mise en évidence de leur structure en boucle, l'observation de leur différentes organisations nous permet également de proposer l'existence de nouvelles phases dans le domaine des cristaux liquides lyotropes (phase smectique biaxe, phase TGB).
41
Bowers, Cynthia Thomason. "Transmission Electron Microscopy Analysis of Silicon-Doped Beta-Gallium Oxide Films Grown by Pulsed Laser Deposition." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1580120635333744.
Full text
42
Wagner, Louis. "Precise nuclear data of the 14N(p,gamma)15O reaction for solar neutrino predictions." Helmholtz-Zentrum Dresden-Rossendorf, 2018. https://tud.qucosa.de/id/qucosa%3A31122.
Full textAbstract:
The 14N(p,gamma)15O reaction is the slowest stage of the carbon-nitrogen-oxygen cycle of hydrogen burning and thus determines its reaction rate. Precise knowledge of its rate is required to improve the model of hydrogen burning in our sun. The reaction rate is a necessary ingredient for a possible solution of the solar abundance problem that led to discrepancies between predictions of the solar standard model and helioseismology. The solar 13N and 15O neutrino fluxes are used as independent observables that probe the carbon and nitrogen abundances in the solar core. This could settle the disagreement, if the 14N(p,gamma)15O reaction rate is known with high precision. After a review of several measurements its cross section was revised downward due to a much lower contribution by one particular transition, capture to the ground state in 15O. The evaluated total relative uncertainty is still 7.5%, in part due to an unsatisfactory knowledge of the excitation function over a wide energy range. The present work reports experimentally determined cross sections as astrophysical S-factor data at twelve energies between 0.357 - 1.292 MeV for the strongest transition, capture to the 6.79 MeV excited state in 15O with lower uncertainties than before and at ten energies between 0.479 - 1.202 MeV for the second strongest transition, capture to the ground state in 15O. In addition, an R-matrix fit is performed to estimate the impact of the new data on the astrophysical relevant energy range. The recently suggested slight S-factor enhancement at the Gamow window could not be confirmed and differences to previous measurements at energies around 1 MeV were observed. The present extrapolated zero-energy S-factors are S_6.79(0) = (1.19+-0.10) keV b and S_GS(0) = (0.25+-0.05) keV b and they are within the uncertainties consistent with values recommended by the latest review.Die 14N(p,gamma)15O Reaktion ist die langsamste Phase im Bethe-Weizsäcker-Zyklus des Wasserstoffbrennens und bestimmt deshalb die Reaktionsrate des gesamten Zyklus. Präzise Werte für die Reaktionsrate sind notwendig um das Wasserstoffbrennen in unserer Sonne besser zu verstehen. Besonders das Problem widersprüchlicher Ergebnisse aus Vorhersagen des aktuellen Sonnenmodells und helioseismologischen Experimenten könnte durch genauer bekannte 14N(p,gamma)15O Reaktionsraten aufgelöst werden. Dafür soll der solare 13N und 15O Neutrinofluss von den beta+-Zerfällen als direkter Informationsträger über die Häufigkeit von Stickstoff und Kohlenstoff im Sonneninneren genutzt werden. Der für die Berechnung der Häufigkeiten benötigte Wirkungsquerschnitt der 14N(p,gamma)15O Reaktion wurde in einer Evaluation verschiedener Messungen reduziert, da der Anteil des direkten Protoneneinfang mit Übergang in den Grundzustand deutlich weniger zum gesamten Wirkungsquerschnitt beiträgt als zuvor angenommen. Die evaluierte relative Gesamtunsicherheit ist mit 7.5% dennoch hoch, was zu einem großen Teil an ungenügendem Wissen über die Anregungsfunktion in einem weiten Energiebereich liegt. In der vorliegenden Arbeit werden experimentell ermittelte Wirkungsquerschnitte in Form von astrophysikalischen S-Faktoren für zwei Übergänge vorgestellt. Für den stärksten Übergang, den Protoneneinfang zum angeregten Zustand bei 6.79 MeV in 15O, wurden zwölf S-Faktoren bei Energien zwischen 0.357 – 1.292 MeV mit geringeren Unsicherheiten als zuvor ermittelt und für den direkten Übergang in den Grundzustand zehn Werte zwischen 0.479 – 1.202 MeV. Außerdem wurde ein R-Matrix Fit durchgeführt um den Einfluss der neuen Daten auf Extrapolationen zum astrophysikalisch relevanten Energiebereich zu prüfen. Die kürzlich vorgeschlagene Erhöhung des S-Faktors im Gamow-Fenster konnte nicht bestätigt werden und es wurden auch Unterschiede zu bisherigen Messungen im Energiebereich um 1 MeV deutlich. Die neuen extrapolierten S-Faktoren sind S679(0) = (1.19±0.10) keV b und SGS(0) = (0.25 ± 0.05) keV b und sie stimmen mit den von der Evaluation empfohlenen Werten im Rahmen ihrer Unsicherheiten überein.
43
Tsao, Wei-chiao, and 曹惟喬. "Strategic analysis of doping behavior in tournaments." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/21487782241244206702.
Full textAbstract:
碩士國立中山大學
經濟學研究所
104
In view of the endorsement rampant, in order to enhance athletic performance to get the opportunity to endorsement, the star players have no hesitation to violate ethical standard to use illegal drugs. We focus on the interaction among the star players, fans, and the firms to research the players’ doping motivation. Then, extend to discuss players’ considering doping strategy based on catching probability. Our thesis starts off the tournament model with two star players. Both of them strive for reputation, but suffering for effect on own performance from opponent’s reputation. The result reveals that the players consider advantageous position or the problem of waves urging waves, having incentive to dope, because excellent or bad performance would change the perception of the fans unobtrusively and imperceptibly. Then, indirectly affect sales of endorsement products and firm profit, and finally influence the player’s endorsement fees. The presence of the performance on the court will be an indirect impact on endorsement fees, the star players will pay more attention on their performance. To extend two players’ process of tournament, we use game theory to find out the players’ doping and no doping conditions, and we get an inference that the greater the star player’s endowment is, the higher the doping probability is.
44
Durst, Olivia. "Athletes’ values, attitudes and justifications for the doping ban: an analysis of Canadian retired and current National Volleyball Team players’ perspectives." 2013. http://hdl.handle.net/1993/18309.
Full textAbstract:
This thesis examines the attitudes and justifications athletes have in regards to doping in sport, and specifically the current doping ban. A historical analysis of anti-doping policy development in Canada was completed to determine how the current anti-doping system operates in Canada. Semi-structured interviews were then conducted with retired and current members of the Women’s and Men’s Canadian National Volleyball Teams. Content analysis was used to analyze the interview transcripts and to draw out the resulting themes. From the interviews it emerged that the Canadian volleyball athletes participating in this study viewed the doping ban as a list of rules they must follow in order to remain eligible to compete. The athletes’ perspectives on the doping ban differ from the reasons historically and currently provided by anti-doping organizations, as the athletes participating in this study did not discuss values in their reasons for following the doping ban in sport.
45
Gonçalves, Mariana Gomes. "Doping e o Papel do Farmacêutico." Master's thesis, 2018. http://hdl.handle.net/10316/84499.
Full textAbstract:
Relatório de Estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de FarmáciaO estágio curricular faz parte do programa do Mestrado Integrado em Ciências Farmacêuticas, tendo como objetivo o enquadramento da componente teórica na prática laboral, levando a um sinergismo entre a faculdade e o mercado de trabalho.Desta forma, tive oportunidade de estagiar em dois locais distintos, na Farmácia de São Martinho e na Farmácia do Hospital Dr. Nélio Mendonça, proporcionando uma experiência enriquecedora para o desenvolvimento das minhas competências.O presente documento contém uma análise SWOT dos dois estágios, onde através de uma visão retrospetiva avalio as forças, as fraquezas, as ameaças e as oportunidades relativas ao meu percurso durante o estágio.Numa segunda parte, abordo o doping como uma temática cada vez mais em evolução, não só devido ao aparecimento de novas substâncias e métodos para desenvolvimento da performance física, assim como o uso de novas estratégias para evitar a deteção dessas mesmas substâncias.Os esteróides anabólicos androgénicos apresentam-se como a classe de substâncias mais encontradas nos laboratórios de antidopagem. Apesar disso, a sua deteção mostra-se complexa, especialmente dos esteróides produzidos endogenamente. Estes são analisados com base na interpretação de um perfil esteroidal individual do atleta, através do uso de um modelo estatístico que tem em conta as amostras obtidas anteriormente. Quando a amostra analisada ultrapassa os valores de referência limite, uma análise confirmatória por GC/C/IRMS torna-se necessária, existindo no entanto diversas limitações na sua deteção.O farmacêutico, como profissional de saúde especialista no medicamento, é um pilar essencial na ajuda ao atleta e toda a equipa envolvente, através do aconselhamento, monitorização e educação acerca das substâncias e métodos considerados ilícitos pelas agências de antidopagem, assim como também atua na prevenção do doping inadvertido através do uso de suplementação e medicação.
The curricular internship is part of the Integrated Master's Program in Pharmaceutical Sciences, with the purpose of framing the theoretical component in work practice, leading to a synergism between the faculty and the labor market.In this way, I had the opportunity to practice at two different sites, Farmácia de São Martinho and Farmácia Dr. Nélio Mendonça Hospital, providing an enriching experience for the development of my skills.This document contains a two-stage SWOT analysis where, through a retrospective analysis, I assess the strengths, weaknesses, threats, and opportunities regarding my path during the internship.Doping is an increasingly evolving subject, not only due to the appearance of new substances and methods for the improvement of physical performance, as well as the use of new strategies to avoid the detection of these same substances.Anabolic androgenic steroids are the most common class of substances found in anti-doping laboratories. Although, its detection is complex, especially in endogenously produced steroids. These are analyzed based on the interpretation of an individual steroid profile of the athlete, through the use of a statistical model that takes into account the samples obtained previously. When the analyzed sample exceeds the limit reference values, it leads to a subsequent confirmatory GC / C / IRMS analysis. Though, there are several limitations to its detection.The pharmacist, as a health professional drug specialist, is a fundamental piece in helping the athlete and all surrounding team through counseling, monitoring and education about substances and methods considered illegal by anti-doping agencies, as well as preventing unintentional doping through the use of supplementation and medication.
46
Chen, Chung-Hsien, and 陳忠賢. "Fabrication of power devices and doping concentration analysis with NTD." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/83003608082167968135.
Full text
47
Chen, Wei-Shin, and 陳偉信. "Capaciatance-Voltage Analysis on n-ZnSe with Various Doping Densities." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/19798527867378126925.
Full textAbstract:
碩士國立中山大學
物理學系研究所
90
The method of C-V analysis is a powerful technique to determine the parameter of MOS (metal oxide semiconductor) structure. In this study, we fabricate the MOS structure with rf magnetron sputtering of Ta2O5 on n-ZnSe surface. The n-ZnSe’s with various carrier concentrations have different electrical property. Interfaces of various Ta2O5/ZnSe have different properties, for examples flatband voltage, threshold voltage, the mobile oxide charge density, and the effective oxide charge concentration and etc. We find that the interfaces of the Ta2O5/ZnSe MOS structure have low mobile charges and interface trap charges. Thus Ta2O5/ZnSe MOS structure may be worthy to develop further.
48
Li-Chung, Ting, and 丁立中. "Structure analysis of Ru-based Sr2YRuO6 2116 Cu-doping system." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/72481161629928615664.
Full textAbstract:
碩士淡江大學
物理學系
89
This thesis presents a systematic study on the structure properties of Cu-doped double perovskites Sr2YRu1-XCuXO6 (2116). The double perovskites compound is a known antiferromagnetic insulator, and it was observed superconductivity in this compound system with small amount of Cu-doping, a 50K superconducting transition temperature as determined by both resistive and magnetic measurement. The common features of high Tc superconductor is consisting of layered structure with CuO2 plane, however this structure contains no CuO2 plane. An impurity phase was observed at 2θ=33.1° in powder X-ray diffraction pattern. The amount of Cu-doping was adjusted from 0 to 0.1 mole and the impurity phase was scaled by high resolution X-ray. Furthermore for getting the value of unit cell constant, peak of (004) plane was scaled and fitted to determine the c value. A substantial increase of impurity phase was observed and the unit cell constant c stops expanding at Cu concentration is more than 0.04 mole.
49
Jia-YunJhang and 張嘉芸. "Stability Analysis of Lead-Free Perovskite Solar Cells by Cation Doping." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/tknaa9.
Full textAbstract:
碩士國立成功大學
光電科學與工程學系
107
The emerging lead-Free perovskite has attracted enormous attention due to its eco-friendly nature. Among the lead-free perovskites, tin-based perovskite has lots of excellent optoelectronic properties, such as appropriate band gap of 1.41 eV, high absorption coefficient (105 cm-1), long carrier length (500 nm) and so on. However, the easy oxidation of Sn2+ to Sn4+ in tin-based perovskite will create vancancy which alter the electronic properties of tin-based perovskite. As a result, the oxidation reaction is a key issue for stabilizing the tin-based perovskite and the device performance. In this study, we codope HAI and EDAI2 in FASnI3 perovskite to stabilize the perovskite film as well as device stability. The device performance is optimized at a precursor ration HAI:FAI=3:97 with a doping level of 10% EDAI2 to attain a power conversion efficiency (PCE) of 5.17%. The device works stably on different temperature at 80C, 100C, and 120C for 12hr in a globe box. Additionally, the device without encapsulation displayed can survive for 9 hr in air. Doping cation in tin-based perovskite paves the way for stable tin-based perovskite solar cells. The new material is doped in lead-free perovskite to help promotion of the efficiency and stability.
50
Wang, Xuanye. "Graphene characterization and device fabrication: doping analysis, strains engineering towards terahertz radiation." Thesis, 2017. https://hdl.handle.net/2144/27047.
Full textAbstract:
As one of the most promising two-dimensional materials, graphene’s outstanding electrical, mechanical and optical properties have made many new devices possible. Its ultra-thin thickness makes both the fabrication and characterization of graphene-based device challenging. In my thesis, I will discuss different approaches to fabricate and characterize graphene devices for the use in transport and THz radiation devices, as well as strain engineering. These approaches could be potentially used to produce next generation electrical devices, photonics devices and generate ultra-high pseudomagnetic fields. To analyze graphene’s quality, I use multi-variable Raman spectroscopy for identifying graphene’s defect density, strain and doping. A case study of strain redistribution on a silicon dioxide grating with sub-diffraction limit resolution of the strain variation is presented, where atomic force microscopy and Raman spectroscopy are applied for characterization. The strain redistribution is used to determine the strain dependent friction between graphene and the substrate. This work has also lead to more precise determination of the strain and shear response using the 2D phonon band. Improvements of the electrical property of graphene is achieved by using graphene encapsulated between atomically flat hBN layers as well as tuning surface hydrophobicity via substrate salinization. This also provides an improved method to optically determine charge density in graphene with order of magnitude enhancement in sensitivity.