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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
421

The impact of recent policy revisions addressing doping and gender rules on women track and field student-athletes in China

He, Dongwan 25 August 2015 (has links)
Women’s involvement in sport has remained a critical issue in society for several decades. Sex verification and drug testing are two methods that have been used to regulate women’s eligibility to compete in international sports competitions based on their testosterone levels. Organizations such as the International Olympic Committee (IOC) and World Anti-Doping Agency (WADA) have published and updated policies and rules that set eligibility criteria for who can compete in women’s sport and under what conditions. However, the academic literature addressing Chinese women’s perspectives on international sex verification and drug testing policies available in English is extremely limited. This study investigates how recent policy revisions regarding doping and sex eligibility rules impact women student- athletes competing in track and field at the university level in China. Using qualitative research methods, this thesis analyzes the impact of recent doping and gender policies on a sample of Chinese female student-athletes. / October 2015
422

Nitrogen-doped DLC deposition by hot filament and inductively coupled plasma sputtering for biomedical applications

2013 September 1900 (has links)
The heart is one of the most important organs of the human body and cardiovascular diseases remain the biggest cause of deaths worldwide. Today, due to the aging of the population and the growing demand for cardiovascular implants, improving the performance of artificial surfaces of vascular prostheses is highly desired. The common material for fabricating prostheses, such as stents used to remedy narrow and weak arteries, is Fluorocarbon polymers or expanded Polytetrafluoroethylene (ePTFE, Gore-tex). Although these polymers are well known for chemical inertness, thermal stability and low friction, they can cause early thrombosis (forming clot) and coagulation in blood vessels and require periodic replacement. Modifying the surface properties of Polytetrafluoroethylene (PTFE) by coating with carbon-based materials may improve its blood compatibility. Carbon-based coatings have properties similar to biomedical components, such as low friction, bioinertness, high wear resistance and exceptional hardness. Plasma processing methods are commonly used for coating thin films on various materials including carbon-based components. Plasma-based processes are also widely used in the aerospace, automotive, steel and biomedical industries. For example, extending the lifetime of surgically implanted hip joints and cutting tools are biomedical and industrial applications of plasma-based material processing respectively. Plasma-assisted deposition techniques are commonly used for carbon-based coating including nitrogen-doped amorphous carbon (a-C) films. In this thesis, PTFE samples with different thickness and roughness characteristics are used as substrates and diamond-like carbon (DLC) is deposited on them by simultaneous plasma-assisted sputtering and chemical vapour deposition (CVD). Hot filament plasma and ICP (Inductively coupling plasma) are used to coat DLC on PTFE and silicon (Si) substrates under various plasma conditions. The latter is the first report on the techniques to coat DLC by ICP plasma sputtering. This new technique (ICP-sputtering) is developed to improve low deposition rate and high temperature deposition of previous method (Hot filament plasma sputtering). Advantageous of this new developed method (ICP-sputtering) are discussed and compared with the previous method in this thesis. Various amount of nitrogen is introduced to the plasma chambers and the effect of nitrogen dopant is also studied using different characterization techniques for chemical, electronic and morphological properties of coated films. sp2 and sp3 contents were also estimated in amorphous carbon (a-C) and nitrogenated amorphous carbon (a-CN) films. Characterization techniques used for in this thesis are including SEM (scanning electron microscopy), AFM (atomic force microscopy), Raman spectroscopy, XAS (x-ray absorption spectroscopy), XES (x-ray emission spectroscopy), XPS (x-ray photoelectron spectroscopy) and XRD (x-ray diffraction).
423

A STUDY ON ATOMICALLY THIN ULTRA SHORT CONDUCTING CHANNELS, BREAKDOWN, AND ENVIRONMENTAL EFFECTS

Sundararajan, Abhishek 01 January 2015 (has links)
We have developed a novel method of producing ultra-short channel graphene field effect devices on SiO2 substrates and have studied their electrical transport properties. A nonlinear current behavior is observed coupled with a quasi-saturation effect. An analytical model is developed to explain this behavior using ballistic transport, where the charge carriers experience minimal scattering. We also observe multilevel resistive switching after the device is electrically stressed. In addition, we have studied the evolution of the electrical transport properties of few-layer graphene during electrical breakdown. We are able to significantly increase the time scale of break junction formation, and we are able to observe changes occurring close to breakdown regime. A decrease in conductivity along with p−type doping of the graphene channel is observed as the device is broken. The addition of structural defects generated by thermal stress caused by high current densities is attributed to the observed evolution of electrical properties during the process of breakdown. We have also studied the effects of the local environment on graphene devices. We encapsulate graphene with poly(methyl methacrylate) (PMMA) polymer and study the electrical transport through in situ measurements. We have observed an overall decrease in doping level after low-temperature annealing in dry-nitrogen, indicating that the solvent in the polymer plays an important role in doping. For few-layer encapsulated graphene devices, we observe stable n−doping. Applying the solvent onto encapsulated devices demonstrates enhanced hysteretic switching between p and n−doped states.
424

Growth Control and Manipulation of Morphology, Crystallinity, and Physical Properties of Tin (IV) Oxide Nanostructures: Granular Nanocrystalline Films and One-Dimensional Nanostructures

Bazargan, Samad January 2011 (has links)
A variety of nanostructures of tin (IV) oxide (TO) are synthesized using two fabrication methods: a solution spin-coating method followed by post-annealing in an oxygen flow and a newly developed catalyst-assisted pulsed laser deposition (PLD) technique. The spin-coating method is used to fabricate granular TO films with monodisperse, stable, ultra-small nanocrystallites (4-5 nm in size), the size of which is found to increase exponentially with post-anneal above 500??C. These nanocrystalline films are conductive and highly transparent, and their bandgap shows broadening due to a high carrier concentration. Their resistivity behavior as a function of temperature in the 50-280 K range can be explained by a two-medium transport model, i.e. transport through the crystalline grains and across the grain boundaries, and through the charge-depletion layer, where a potential barrier is found for transport across the grain boundaries. Electronic transport in these films follows a 3D-variable range hopping model, which reveals an increase in the localization length of carriers with increasing the TAnneal above the onset of exponential growth at TAnneal= 500??C. By homogenously doping Eu3+ in these nanocrystalline films up to a high doping level of ~ 8%, optical luminescence and magnetic orderings can be introduced into these nanocrystalline TO films. Both characteristic Eu3+ emission and defect-related TO emissions are observed in the otherwise transparent TO films upon UV-excitation. In spite of the non-magnetic nature of Eu3+ ions, magnetic orderings appear in the highly doped TO films below 50 K upon the emergence of Eu2Sn2O7 phase. In the second part of this work, we employ a layer of gold nanoislands with controlled sizes (10-50 nm) as catalysts for pulsed laser deposition of TO nanostructures. Highly crystalline TO nanobricks, cuboid nanoparticles, nanowires and nanobelts are obtained for the first time through vapour-solid or vapour-liquid-solid (VLS) mechanisms. Of particular interest are the micron long one-dimensional (1D) nanowires and nanobelts, with the smallest square and rectangular cross-sections, respectively, ever reported. These single-crystalline nanostructures are obtained at relatively low temperatures of 600??C, for nanowires, and 500??C, for nanobelts, and their cross-sectional sizes can be easily controlled by the size of the gold nanoislands. The nanobelts are found to grow along the [100] and [101] axes, while the nanowires appear to grow along the [100] axis. The growth evolution of the nanobelts are also investigated in detail revealing their VLS growth mode and their single-crystalline structure throughout the growth, which opens the prospect of controlling their growth axis and consequently their side-surface planes by pinning the base to the substrate at the desired crystalline orientation. Together, the two fabrication methods developed in the present work offer facile approaches to growing two scientifically and technologically important classes of TO nanostructures, i.e., nanocrystalline film and 1D nanostructures. Thorough characterization of the resulted nanostructured materials using advanced microscopic, spectroscopic and other techniques, including Helium Ion Microscopy, has been provided. Modification of structure, morphology and physical properties of these functional nanostructured materials are also illustrated by controlling the growth parameters and by (Eu-)doping, which pave the way for introducing new properties for applications in chemical sensing, (opto)electronics and displays.
425

A Study of Mechanisms Governing Single Walled Carbon Nanotube Thin Film Electric Biosensors

Ward, Andrew 07 January 2015 (has links)
The successful fabrication and characterization of two chemiresistive platforms for biomolecule detection was demonstrated by this work. The Si/Silica based single walled nanotube thin film (SWNTTF) platform was developed to understand the effect of device geometry on pH and M13 bacteriophage sensing capabilities as well as the underlying mechanisms governing SWNTTF chemiresistive biosensors. The dominant mechanism of sensing switched from direct chemical doping to electrostatic gating when the target analyte changed from H+/OH- ions in pH testing to whole viruses. The experimental limit of detection for M13 for this platform was 0.5pM and an increased sensitivity as well as variability was observed in devices with smaller channel widths. Preliminary device calibration was completed in order to correlate a resistance response to a bulk M13 concentration. The polyethylene terephthalate (PET) based SWNTTF platform was developed to demonstrate the commercial potential of SWNTTF chemiresistive biosensors by detecting relevant concentrations of brain natriuretic peptide (BNP) on economically viable substrates. The pH response of these chemiresistors confirmed that chemical doping was the cause for resistance change in the SWNTTFs. The preliminary results demonstrated successful BNP detection at 50pg/mL using both aptamers and antibodies as recognition elements. Using SWNTTFs as the transducing element of chemiresistors allowed for further understanding of electrical mechanisms of sensing as well as achieving sensitive, real-time and reproducible electrical virus and biomolecule detection. Although these platforms do not achieve ultrasensitive limits of detection, they demonstrate the commercial potential of platforms using SWNTTFs as the transducing element of electrical biomolecule sensors.
426

Elektronische Eigenschaften dotierter polyzyklischer aromatischer Kohlenwasserstoffe

Mahns, Benjamin 28 January 2015 (has links) (PDF)
In der vorliegenden Arbeit wurde die elektronische Struktur verschiedener undotierter und mit Alkalimetallen beziehungsweise 2,3,5,6-Tetrafluoro-7,7,8,8-tetracyanoquinodimethan (F 4 TCNQ) dotierter, polyzyklischer aromatischer Kohlenwasserstoffe (PAK) untersucht. Diese Untersuchungen waren motiviert durch verschiedene Veröffentlichungen in denen supraleitendes Verhalten an unterschiedlichen alkalimetalldotierten PAK beschrieben wurde. Erste Studien erfolgten an undotiertem 1,2:8,9-Dibenzopentacen (DBP) und Pentacen unter Nutzung von Photoelektronenspektroskopie (PES), Elektronenenergieverlustspektroskopie (EELS) und Dichtefunktionaltheorie (DFT). Die spektroskopischen Methoden zeigten für beide Materialien eine große Ähnlichkeit der elektronischen Zustände, vor allem im niederenergetischen Bereich, welche durch die theoretischen Ergebnisse bestätigt wurde. Die elektronische Ähnlichkeit beider Materialien ist im starken Gegensatz zu dem in der Literatur bei Dotierung beobachteten Verhalten, bei dem Pentacen zum Mott-Isolator wird, während DBP Supraleitung zeigt. Weitere Untersuchungen erfolgten an Picen und Coronen. Bandstrukturrechnungen zeigten, dass Picen vermutlich ein stark korreliertes Elektronensystem besitzt. Neben dem mit PES ermittelten Ionisationspotential und der Austrittsarbeit waren auch die mit EELS gemessenen optischen Bandlücken der beiden Materialien sehr ähnlich. Unterschiede zeigten sich hingegen vor allem in der Dichte der gemessenen Zustände von Picen und Coronen am Ferminiveau. Bei der Untersuchung der elektronischen Eigenschaften von mit Kalium-dotierten Picen und Coronen wurde trotz der erfolgreichen Dotierung in keinem der untersuchten Filme eine Zustandsdichte am Ferminiveau beobachtet somit wurde auch keiner der untersuchten Filme metallisch. Dasselbe Verhalten konnte auch für Natrium-dotierte Filme beobachtet werden. Eine Diskussion dieses Ergebnisses, welches im Gegensatz zu der von anderen Gruppen in dotierten Molekülen beobachteten Supraleitung steht, erfolgte im Hinblick auf die Bildung unterschiedlich dotierter Phasen, Elektron-Phonon-Kopplung, der Formierung von Bi-Polaronen und Korrelationseffekten. Für ein weitergehendes Verständnis der dotierungsinduzierten elektronischen Eigenschaften in den untersuchten Molekülen wurden diese nicht nur mit Alkalimetallen, sondern teilweise auch mit elektronenziehenden Molekülen wie F 4 TCNQ interkaliert. Dabei entstanden Kristalle verschiedener Ladungstransfersalze. Eine ausführliche Charakterisierung erfolgte für Picen/F 4 TCNQ-Kristalle, welche im Rahmen dieser Arbeit zum ersten Mal hergestellt und untersucht wurden. Dabei wurde zunächst deren Kristallstruktur mit Röntgendiffraktometrie (XRD) bestimmt. Eine Abschätzung der Größe des Ladungstransfers innerhalb der Molekülpaare aus Picen/ F 4 TCNQ erfolgte über Infrarot- und Bindungslängendaten, die auf diese Weise gefunden Werte wurden zusätzlich durch DFT-Rechnungen untermauert. Transportmessungen zeigten außerdem, dass die hergestellten Kristalle entlang ihrer Hauptwachstumsrichtung Isolatoren sind. Die Untersuchung der elektronischen Eigenschaften wurde mit EELS und PES an Picen/ F 4 TCNQ -Dünnfilmen durchgeführt, welche durch die Verdampfung der Einkristalle hergestellt wurden. Die Molekülpaare zeigen einen Ladungstransfer, der neue elektronische Anregungen im Niederenergiebereich der mit EELS gemessenen Verlustfunktion hervorruft. Im weiteren Verlauf der Arbeit erfolgte eine Diskussion bezüglich des Charakters und der Lokalisierung dieser neuen Anregungen. Bei den PES-Messungen zeigte sich der Ladungstransfer durch energetische Verschiebungen in den gemessen Rumpfniveauspektren sowie durch im Vergleich zu den reinen Materialien deutlich veränderte Ionisationspotentiale. Trotz des erfolgreichen Ladungstransfers und der damit verbundenen Füllung von unbesetzten Zuständen mit Elektronen in F 4 TCNQ wurde jedoch in den Valenzbandspektren keine Emission am Ferminiveau beobachtet. DFT-Rechnungen ermöglichten schließlich Aussagen über den Charakter des Ladunstransfers und die daraus resultierende, fehlende Zustandsdichte am Ferminiveau.
427

Processing and Characterization of P-Type Doped Zinc Oxide Thin Films

Myers, Michelle Anne 03 October 2013 (has links)
Applications of zinc oxide (ZnO) for optoelectronic devices, including light emitting diodes, semiconductor lasers, and solar cells have not yet been realized due to the lack of high-quality p-type ZnO. In the research presented herein, pulsed laser deposition is employed to grow Ag-doped ZnO thin films, which are characterized in an attempt to understand the ability of Ag to act as a p-type dopant. By correlating the effects of the substrate temperature, oxygen pressure, and laser energy on the electrical and microstructural properties of Ag-doped ZnO films grown on c-cut sapphire substrates, p-type conductivity is achieved under elevated substrate temperatures. Characteristic stacking fault features have been continuously observed by transmission electron microscopy in all of the p-type films. Photoluminescence studies on n-type and p-type Ag-doped ZnO thin films demonstrate the role of stacking faults in determining the conductivity of the films. Exciton emission attributed to basal plane stacking faults suggests that the acceptor impurities are localized nearby the stacking faults in the n-type films. The photoluminescence investigation provides a correlation between microstructural characteristics and electrical properties of Ag- doped ZnO thin films; a link that enables further understanding of the doping nature of Ag impurities in ZnO. Under optimized deposition conditions, various substrates are investigated as potential candidates for ZnO thin film growth, including r -cut sapphire, quartz, and amorphous glass. Electrical results indicated that despite narrow conditions for obtaining p-type conductivity at a given substrate temperature, flexibility in substrate choice enables improved electrical properties. In parallel, N+-ion implantation at elevated temperatures is explored as an alternative approach to achieve p-type ZnO. The ion implantation fluence and temperature have been optimized to achieve p-type conductivity. Transmission electron microscopy reveals that characteristic stacking fault features are present throughout the p-type films, however in n-type N-doped films high-density defect clusters are observed. These results suggest that the temperature under which ion implantation is performed plays a critical role in determining the amount of dynamic defect re- combination that can take place, as well as defect cluster formation processes. Ion implantation at elevated temperatures is shown to be an effective method to introduce increased concentrations of p-type N dopants while reducing the amount of stable post-implantation disorder. Finally, the fabrication and properties of p-type Ag-doped ZnO/n-type ZnO and p-type N-doped ZnO/n-type ZnO thin film junctions were reported. For the N-doped sample, a rectifying behavior was observed in the I-V curve, consistent with N-doped ZnO being p-type and forming a p-n junction. The turn-on voltage of the device was ∼2.3 V under forward bias. The Ag-doped samples did not result in rectifying behavior as a result of conversion of the p-type layer to n-type behavior under the n- type layer deposition conditions. The systematic studies in this dissertation provide possible routes to grow p-type Ag-doped ZnO films and in-situ thermal activation of N-implanted dopant ions, to overcome the growth temperature limits, and to push one step closer to the future integration of ZnO-based devices.
428

Investigation Of Thin Semiconductor Coatings And Their Antimicrobial Properties

Erkan, Arcan 01 August 2003 (has links) (PDF)
Regular disinfection of surfaces is required in order to reduce the number of microorganisms, unable to transmit infections and maintaining the surfaces sterilized. For this purpose, antimicrobial thin film coatings on the various surfaces such as glass and ceramic surfaces, capable of killing harmful microorganisms are being investigated. Generally a semiconducting material which can be activated by UV light tends to exhibit a strong antimicrobial activity. With holes (h+) and hydroxyl radicals (OH*) generated in the valence band, electrons and the superoxide ions (O2-) generated in the conduction band, illuminated semiconductor photocatalysts can inactivate microorganisms by participating in a series of oxidation reactions leading to carbon dioxide. The aim of this current study was developing semiconductor coatings, increasing the photocatalytic activity of these coatings by metal doping, particularly palladium doping, and investigating the antimicrobial properties of these coatings. In this study, glass surfaces were coated with titanium dioxide (TiO2), tin dioxide (SnO2) and palladium doped TiO2 and SnO2 sol-gels. After achieving thin, dense and strong coatings, antimicrobial properties of the coatings were investigated by applying the indicator microorganisms directly onto the coated glasses. Different cell wall structure of microorganisms can strongly affect the photocatalytic efficiency of the coatings. Hence Escherichia coli as a Gr (-) bacteria, Staphylococcus aereus as Gr (+) bacteria, Saccharomyces cerevisiae as a yeast and Aspergilus niger spores were used in the experiments. Photocatalytic efficiency of TiO2 was better than SnO2 coatings. Palladium doping increased the antimicrobial activity of both coatings. The reduction efficiencies were found to decrease in the following order of E. coli [Gr (-)] &gt / S. aereus [Gr (+)] &gt / S.cerevisiae (yeast) &gt / A. niger spores. The complexity and the density of the cell walls increased in the same order. As a result of this study, with the coating that shows the best photocatalytic activity, 98% of Escherichia coli, 87% of Staphylococcus aereus, 43% Saccharomyces cerevisiae were killed after 2 hours illumination.
429

Untersuchungen zur Pharmakokinetik von Coffein, Theophyllin und Theobromin beim Hund nach Aufnahme von Kaffee, Tee und Schokolade

Loeffler, Bernd Matthias Nikolaus 28 November 2004 (has links) (PDF)
Loeffler, Bernd Matthias Nikolaus Untersuchungen zur Pharmakokinetik von Coffein, Theophyllin und Theobromin beim Hund nach Aufnahme von Kaffee, Tee und Schokolade aus dem Institut für Pharmakologie, Pharmazie und Toxikologie der Veterinärmedizinischen Fakultät der Universität Leipzig Leipzig im April 2000 (83 S., 24 Abb., 12 Tab., 187 Lit.) Methylxanthine stimulieren das zentrale Nervensystem, das Herz-Kreislauf-System und führen zur Bronchodilatation. Die Ergebnisse der Dopinguntersuchungen im Windhundrennsport zeigen, daß die Methylxanthine wie Coffein, Theophyllin und Theobromin nicht nur therapeutisch, sondern auch mißbräuchlich zur Leistungssteigerung eingesetzt werden. In der vorliegenden Studie wurde die Pharmakokinetik von Coffein, Theophyllin und Theobromin bei Hunden untersucht. Speziell in Hinblick auf die Dopingproblematik im Windhundsport wurden bei den Hunden zusätzlich Plasma- und Harnproben nach Applikation von Kaffee, Tee und Schokolade analysiert. Nach oraler Applikation von Coffein und Theophyllin (10 mg/kg KM) wurden im Plasma mittlere Konzentrationsmaxima an Coffein von 61,8 µmol/l und an Theophyllin von 42,5 µmol/l nach 1,6 bzw. 4,8 Stunden erreicht. Die Elimination erfolgte jeweils mit einer Halbwertszeit von etwa 3 Stunden. Im Urin konnten die applizierten Methylxanthine ebenfalls nachgewiesen werden, nach Applikation von Coffein war Theobromin als Metabolit in hohen Konzentrationen nachweisbar. Nach Aufnahme von Kaffee und Tee durch Hunde konnte in Plasma und Urin Coffein, Theophyllin und Theobromin nachgewiesen werden. Nach Verfütterung von Schokolade wurde im Wesentlichen nur Theobromin gefunden, so daß aus dem Metabolitenmuster der Methylxanthine zum Teil auf das aufgenommene Nahrungsmittel geschlossen werden kann. Um nicht in Konflikt mit geltenden Dopingbestimmungen zu kommen, sollten Hundehalter darauf achten, daß ihre Tiere in den Tagen vor einem Rennen keinen Zugang zu methylxanthinhaltigen Produkten wie Kaffee, Tee und Schokolade haben. / Loeffler, Bernd Matthias Nikolaus Investigations of the pharmacokinetics of caffeine, theophylline and theobromine in the dog. Institute of Pharmacology, Pharmacy and Toxicology of the Veterinary Faculty of the University of Leipzig Leipzig, April 2000 (83 p., 24 fig., 12 tab., 187 ref.) Methylxanthines are often used as stimulants of the central nervous system, of the cardiovascular system and as bronchodilators. Doping samples of racing greyhounds demonstrate that methylxanthines like caffeine, theophylline, and theobromine besides their therapeutic use, are illegally used to strengthen the animals. In this study the pharmacokinetics of caffeine, theophylline and theobromine in dogs were examined. Additionally samples of plasma and urine were taken after application of coffee, tea, and chocolate. After oral application of caffeine and theophylline (10 mg/kg) highest plasma concentrations of caffeine were about 61.8 µmol/l and of theophylline about 42.5 µmol/l after 1.6 and 4.8 hours, respectively. The elimination half-lives for both methylxanthines were 3 hours. The methylxanthines administered could also be detected in the urine, after application of caffeine its metabolite theobromine reached high concentrations. After the administration of coffee and tea to dogs caffeine, theophylline and theobromine can be found in plasma and urine. After the feeding of cocoa products (chocolate) theobromine was the predominant methylxanthine to be analysed. Therefore the quantitative relationship of the various methylxanthine metabolites detected can indicate the origin of the ingested methylxanthines. In order to avoid violation of doping regulations, dog owners should assure that their animals have no access to methylxanthine-containing diets in the days before racing competitions.
430

Detecció del consum d'agents anabolitzants en humans: estratègies alternatives de preparació de mostres i anàlisi instrumental

Marcos del Águila, Josep 28 June 2004 (has links)
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.

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