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\"Medida de nitrogênio profundo em aços especiais\" / Measure of Nitrogen in Special SteelCurado, Jessica Fleury 02 February 2007 (has links)
O presente trabalho teve como objetivo caracterizar amostras de aço nitretado, calculando as concentrações elementares e determinando o perfil em profundidade do elemento nitrogênio, utilizado para melhorar a ductibilidade do material. As amostras foram caracterizadas através das técnicas ?Elastic Recoil Detection Analysis? (ERDA) para a determinação da concentração atômica e a análise do perfil em profundidade de elementos leves na região superficial das amostras, ?Particle Induced X-Ray Emission? (PIXE) para a determinação da composição da matriz do aço e a densidade de massa do material, ?Nuclear Resonant Analysis? (NRA) para a determinação da concentração relativa em diferentes profundidades, realizando um perfil em profundidade mais interna do elemento nitrogênio nas amostras e ?X-Ray Diffraction? (XRD) para a determinação da estrutura cristalina das amostras. Para a realização deste estudo foram utilizados dois conjuntos de amostras, o conjunto MET composto por amostras com nitrogênio mais profundo, obtidas a partir de tratamentos térmicos distintos e o conjunto de amostras CEFET, que contém nitrogênio na região superficial das amostras, utilizados para o estudo da técnica NRA. As técnicas utilizadas demonstraram ser sensíveis a modificações realizadas nas amostras, podendo-se concluir que os diferentes processos térmicos aos quais as amostras foram submetidas alteram as características e propriedades das amostras. Os resultados obtidos para as amostras do conjunto MET mostram que apesar de possuírem a mesma concentração na liga metálica, apresentam diferenças nas estruturas cristalinas. Além disso, é possível verificar que o efeito de dissolução do elemento nitrogênio nas amostras em cortes de diferentes profundidades de uma mesma peça pode ser corretamente avaliado ao correlacionar os resultados obtidos pelas diversas técnicas empregadas. / The aim of the present work was to characterize nitrated steel samples, estimating the elemental concentrations and determining the depth profile of the element nitrogen, used to improve the ductility of the material. The samples were characterized using the following techniques: \"Elastic Recoil Detection Analysis\" (ERDA) for the determination of the atomic concentration and analysis of the depth profile for light elements at the surface of the samples, \"Particle Induced X-Ray Emission\" (PIXE) for the determination of the composition of the matrix of the steel and the respective mass density of this material, \"Nuclear Resonant Analysis\" (NRA) for the determination of the relative concentration at different depths, analysing a deeper profile of the element nitrogen at the samples and \"X-Ray Diffraction\" (XRD) for the determination of the crystalline structure of the samples. For the accomplishment of this study two sets of samples have been used: the set of samples MET composed by samples with deeper nitrogen concentration obtained from distinct thermal treatments, and the set of samples CEFET, which contains nitrogen close to the surface area of the samples, used for the study of NRA technique. The techniques demonstrated to be sensible to the modifications carried out in the samples. We were able to identify that the different thermal processes modify the characteristics and properties of the samples. The results obtained for the samples of the first set show that although they have the same concentration in the metallic alloy, they present differences of crystalline structure. Moreover, correlating the results obtained for the various employed techniques it was possible to correctly verify the effect of nitrogen dissolution cuts of different depths of the same piece.
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\"Medida de nitrogênio profundo em aços especiais\" / Measure of Nitrogen in Special SteelJessica Fleury Curado 02 February 2007 (has links)
O presente trabalho teve como objetivo caracterizar amostras de aço nitretado, calculando as concentrações elementares e determinando o perfil em profundidade do elemento nitrogênio, utilizado para melhorar a ductibilidade do material. As amostras foram caracterizadas através das técnicas ?Elastic Recoil Detection Analysis? (ERDA) para a determinação da concentração atômica e a análise do perfil em profundidade de elementos leves na região superficial das amostras, ?Particle Induced X-Ray Emission? (PIXE) para a determinação da composição da matriz do aço e a densidade de massa do material, ?Nuclear Resonant Analysis? (NRA) para a determinação da concentração relativa em diferentes profundidades, realizando um perfil em profundidade mais interna do elemento nitrogênio nas amostras e ?X-Ray Diffraction? (XRD) para a determinação da estrutura cristalina das amostras. Para a realização deste estudo foram utilizados dois conjuntos de amostras, o conjunto MET composto por amostras com nitrogênio mais profundo, obtidas a partir de tratamentos térmicos distintos e o conjunto de amostras CEFET, que contém nitrogênio na região superficial das amostras, utilizados para o estudo da técnica NRA. As técnicas utilizadas demonstraram ser sensíveis a modificações realizadas nas amostras, podendo-se concluir que os diferentes processos térmicos aos quais as amostras foram submetidas alteram as características e propriedades das amostras. Os resultados obtidos para as amostras do conjunto MET mostram que apesar de possuírem a mesma concentração na liga metálica, apresentam diferenças nas estruturas cristalinas. Além disso, é possível verificar que o efeito de dissolução do elemento nitrogênio nas amostras em cortes de diferentes profundidades de uma mesma peça pode ser corretamente avaliado ao correlacionar os resultados obtidos pelas diversas técnicas empregadas. / The aim of the present work was to characterize nitrated steel samples, estimating the elemental concentrations and determining the depth profile of the element nitrogen, used to improve the ductility of the material. The samples were characterized using the following techniques: \"Elastic Recoil Detection Analysis\" (ERDA) for the determination of the atomic concentration and analysis of the depth profile for light elements at the surface of the samples, \"Particle Induced X-Ray Emission\" (PIXE) for the determination of the composition of the matrix of the steel and the respective mass density of this material, \"Nuclear Resonant Analysis\" (NRA) for the determination of the relative concentration at different depths, analysing a deeper profile of the element nitrogen at the samples and \"X-Ray Diffraction\" (XRD) for the determination of the crystalline structure of the samples. For the accomplishment of this study two sets of samples have been used: the set of samples MET composed by samples with deeper nitrogen concentration obtained from distinct thermal treatments, and the set of samples CEFET, which contains nitrogen close to the surface area of the samples, used for the study of NRA technique. The techniques demonstrated to be sensible to the modifications carried out in the samples. We were able to identify that the different thermal processes modify the characteristics and properties of the samples. The results obtained for the samples of the first set show that although they have the same concentration in the metallic alloy, they present differences of crystalline structure. Moreover, correlating the results obtained for the various employed techniques it was possible to correctly verify the effect of nitrogen dissolution cuts of different depths of the same piece.
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Investigation of the properties of thin films grown via sputtering and resistive thermal evaporation : an Ion Beam Analysis (IBA) studyBack, Markus January 2015 (has links)
In this project, thin films are being manufactured by different methods in a thin film deposition set-up and subsequently characterized. This is done in order to determine if the set-up is capable of producing films of sufficient quality to be used for research purposes in the ion physics group of the division of applied nuclear physics at Uppsala University. Both copper and silver films are manufactured by magnetron sputtering deposition. Copper films are also manufactured by evaporation deposition. Deposition is made on Si(001) substrates. The films are analyzed with Rutherford Backscattering Spectrometry (RBS) and Time of Flight- Elastic Recoil Detection Analysis (ToF-ERDA). Results show that the deposition rate of the set-up is much faster compared to the one provided by the manufacturer of the set-up. The purity of the films i.e. the concentrations of the contaminants are found to be in an acceptable range for research applications with an average oxygen contamination of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?1.53%20%5Cpm%200.05%20%25" /> and carbon contamination of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.53%20%5Cpm%200.02%20%25" /> for sputtered copper films. Sputtered silver films were found to have an oxygen contamination of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.28%20%5Cpm%200.012%20%25" /> and a carbon contamination of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.41%20%5Cpm%200.023%20%25" />. Evaporated copper films were found to have an oxygen contamination of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.45%20%5Cpm%200.018%20%25" /> and carbon contamination of <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.31%20%5Cpm%200.013%20%25" />. Traces of gold (<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cprec%200.5%20%25" />) were found exclusively in the sputtered films. Trace amounts of hydrogen could also be detected in both sputtered and evaporated films. The evaporated films are found to show lower contamination by oxygen than the sputtered films, but the manufacturing process employed in this study of evaporated films is not suitable to use for producing thin films of specific thicknesses as there is insufficient data to find a deposition speed. Overall, the set-up is capable of producing thin films with a sufficient quality for it to be used by the department when producing thin films for research. / I det här projektet produceras tunnfilmer med olika metoder i en uppställning för tunnfilmsdeposition och karaktäriseras sedan för att bedöma om maskinen är kapabel att producera filmer av tillräckligt bra kvalitet för att kunna användas i forskningssyften inom jonfysikgruppen på avdelningen för tillämpad kärnfysik på Uppsala Universitet. Både koppar och silverfilmer produceras med magnetronsputtring. Kopparfilmer produceras också med resistiv förångning. Deposition sker på Si(001)-substrat. Filmerna analyseras med Rutherford Backscattering Spectrometry (RBS) och Time of Flight- Elastic Recoil Detection Analysis (ToF-ERDA). Resultaten visar att depositionshastigheten för maskinen är snabbare än det som angetts av företaget som producerar maskinen. Renheten hos filmerna, dvs. koncentrationen av föroreningar, finnes vara inom en acceptabel nivå för forskningstillämpningar med en genomsnittlig syrekontamination på <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?1.53%20%5Cpm%200.05%20%25" /> och kolkontamination på <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.53%20%5Cpm%200.02%20%25" /> för sputtrade kopparfilmer. Sputtrade silverfilmer finnes ha en syrekontamination på <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.28%20%5Cpm%200.012%20%25" /> och en kolkontamination på <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.41%20%5Cpm%200.023%20%25" />. Förångade kopparfilmer finnes att ha en syrekontamination på <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.45%20%5Cpm%200.018%20%25" /> och en kolkontamination på <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?0.31%20%5Cpm%200.013%20%25" />. Spår av guld (<img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Cprec%200.5%20%25" />) hittades enbart i sputtrade filmer. Spår av väte kunde också hittas i både sputtrade och förångade filmer. De förångade filmerna finnes ha lägre syrekontamination än de sputtrade filmerna, men tillverkningsprocessen som används i projektet vid tillverkning av förångade filmer är inte lämplig att använda i produktion av tunnfilmer med specifika tjocklekar då det saknas data för att kunna hitta en depositionshastighet. Totalt sett är uppställningen kapabel att producera filmer av adekvat kvalitet för att de ska kunna användas inom avdelningen för produktion av filmer för forskning.
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Solid Phase Epitaxial Regrowth of alkali ion irradiated a-quartz / Alkaliioneninduzierte Epitaxie von a-QuarzGasiorek, Stanislawa 19 January 2004 (has links)
No description available.
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Fabrication and characterizationof self-supporting Yttrium foilsFejes, Julia, Reineck, Sofia January 2022 (has links)
In this project self-supporting foils with focus on the element yttriumhave been fabricated by means of evaporation and magnetron sputtering.The goal was to see if it was possible to make photochromic selfsupportingyttrium foils. Multiple self-supporting foils were made andsome had suitable properties to be further investigated. The first foilof interest was a plain carbon foil, the second was yttrium layered ontop of a carbon foil, the third was a yttrium-only foil and the fourthwas a yttrium oxyhydride foil. The foils were then subsequentlycharacterized with a newly developed Medium Energy Ion Scattering -Elastic Recoil Detection Analysis (MEIS - ERDA) technique. Thistechnique measures energy loss and recoils (kicked out atoms) of heavyions passing through the self-supporting foils. The measurements weremade with three ion projectile energies, 250, 300 and 320keV. Theprojectiles sent were argon ions. It was noted that the yttriumoxyhydride foil had more hydrogen and oxygen than the yttrium foil. Withoptical measurements it was also possible to confirm that the yttriumoxyhydride foil had photochromic properties. With the knowledge of theparameters used to fabricate these foils, the conclusion is that furtherresearch on self-supporting yttrium oxyhydride is encouraged.
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Accelerator-Based Analysis of Rough Wall Materials From Fusion DevicesPersson Djurhed, Fabian, Forkman, Vilhelm January 2022 (has links)
Time of Flight - Elastic recoil detection analysis (ToF-ERDA) is a method used to analyse the composition of wall samples from fusion devices. All current analysing software for ToF-ERDA assumes that the target is perfectly flat which could create inaccuracies when rough surfaces are analysed. The aim of this project was to get a better understanding of how the roughness of samples from fusion devices affect the results from ToF-ERDA. To investigate this, three existing simulation softwares SIMNRA, TRIM and Potku were used. Programs were developed in order to use these to simulate three different targets with varying roughness, which were modelled as a combination of surfaces of different thicknesses. The results from which were put back into Potku where the differences between the targets could be noted. The study shows that it was possible to apply roughness to the already existing programs and showed similarities between the resulting depth profiles. When applying roughness, the concentration of surface elements decreased at the top of the layer but also went further into the sample. / Time of Flight - Elastic recoil detection analysis (ToF-ERDA) är en metod som används för att analysera kompositionen av prover av väggmaterial från fusionsreaktorer. Alla mjukvaror som används för att analysera datan från ToF-ERDA idag antar att provets yta är helt platt vilket skulle kunna innebära att felaktiga resultat erhålls när så ej är fallet. Målet med där här projektet var att undersöka och skapa en bättre förståelse för hur skrovligheten hos material från fusionsanordningar påverkar resultaten från ToF-ERDA. För att undersöka detta användes tre simulationsmjukvaror, SIMNRA, TRIM och Potku. Program skrevs för att använda dessa för att simulera tre olika material med olika stor skrovlighet, vilka modellerades som en kombination av material med olika tjockt ytskikt. Resultaten från dessa analyserades därefter i Potku där skillnaderna mellan materialen kunde noteras. Studien visar att det är möjligt att implementera ojämnhet i den simulationsprogram som finns idag och flera likheter mellan de resulterande djupprofilerna från de olika simulationsmetoderna uppmärksammades. När högre skrovlighet användes minskade koncentrationerna av ytelementen vid materialets topp men djupet som de når i materialet ökade. / Kandidatexjobb i elektroteknik 2022, KTH, Stockholm
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Data Processing in Accelerator-Based Analysis of Wall Materials From Controlled Fusion DevicesQuoreshi, Arvin January 2021 (has links)
The goal for this project was to analyze and understand the noise of the ion beam analysis technique, Elastic Recoil Detection Analysis (ERDA). This was done by examining two models: Classical models and a prediction model. The prediction model is a parameterized noise distribution model. After examining the models, we concluded that both models had advantages and disadvantages for ERDA analysis. This information could be applicable to our understanding of how ERDA could improve for our analysis of wall materials, which could lead to the overall development of fusion reactors. / Målet för detta projekt var att analysera och förstå brus från jonstråleanalystekniken, Elastic Recoil Detection Analysis (ERDA). Detta gjordes genom att granska två modeller: Klassiska brusreduceringsmodeller och en förutsägelsemodell. Förutsägelsemodellen är en parametrerad brusfördelningsmodell. Efter granskningen av modellerna drog vi slutsatsen att båda modellerna hade fördelar och nackdelar för ERDA-analys. Denna information kan vara tillämplig på vår förståelse av hur ERDA kan förbättras för vår analys av väggmaterial, vilket kan leda till den övergripande utvecklingen av fusionsreaktorer. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm
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Diffusion of volatile fission products in very heavy reactor fuel matricesWikström, Nils January 2024 (has links)
The interplay of nuclear fuel with fission products is key for safe and efficient nuclear power operation. The diffusion of volatile fission products in very heavy reactor fuel matrices was investigated by analysing Zirconium Dioxide and Uranium Nitride, implanted with different ions. The samples were implanted using the 350kV Ion Implanter available at Uppsala University. Zirconium Dioxide was implanted with Xenon, Krypton and Iron, and Uranium Nitride was implanted with Krypton and Zirconium. The samples were then analysed using Time of Flight Elastic Recoil Detection Analysis (ToF-ERDA), Rutherford Backscattering Spectrometry (RBS), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). After the implantation and analysis, the samples were annealed at different times and temperatures. The annealing times were predicted by solving Fick’s second law with numerical methods and using Stopping and Range of Ions in Matter (SRIM) as an initial guess. The results show that annealing times can be predicted by solving Fick’s second law, to first order, and that ion implantation effects the stoichiometry of the samples. Future improvements could include improvement of underlying physics in the annealing predictions, and more extensive measurements performed on a wider range of samples.
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Modificações superficiais em polímeros por feixes iônicos para estudo de biocompatibilidade / Surface modifications in polymers by ion beams for the study of biocompatibilityTrindade, Gustavo Ferraz 07 October 2013 (has links)
Nos dias atuais, grande parte das intervenções cirúrgicas inclui o implante de materiais. Os grandes obstáculos na implantação de próteses em organismos humanos são a coagulação sanguínea em contato com o material devido ao alto grau de ativação plaquetária e a compatibilidade dos tecidos biológicos ao material implantado. Agregando melhorias de propriedades mecânicas a superfícies biocompatíveis, materiais poliméricos apresentam grandes tendências a serem excelentes candidatos a biomateriais para tais aplicações. O objetivo deste trabalho foi realizar modificações superficiais em polímeros através do método de implantação por feixe iônico a fim de se investigar mudanças induzidas em suas propriedades superficiais e estudar possíveis mudanças em sua biocompatibilidade, em específico, sua hemocompatibilidade. Amostras de policarbonato foram irradiadas com feixes de íons de argônio com energia 23 keV e cinco diferentes doses. As superfícies das amostras foram analisadas com medidas de ângulo de contato, microscopia de força atômica, espectroscopia de massa de íons secundários, espectroscopia de fotoelétrons, espectroscopia de retroespalhamento Rutherford, deteção de recuo elástico, espectroscopia de raios-X induzidos por partículas e testes de adesão plaquetária. Os resultados das diferentes técnicas apontaram de forma consistente a uma série de alterações químicas e físicas induzidas nas superfícies das amostras, dentre elas: a perda significativa de hidrogênio nas amostras irradiadas, aumento do grau de reticulação entre as cadeias poliméricas que levou ao aumento de elétron deslocalizados e mudança de coloração, remoção de aditivos, migração à superfície de átomos de argônio implantados e alteração de hidrofilicidade. Ao confrontar todos os resultados obtidos com os resultados dos testes de adesão plaquetária, constatou-se que os efeitos observados aumentam o caráter trombogênico da superfície do policarbonato e que a remoção de aditivos com grupos sulfato e sulfonato após irradiação com argônio teve grande influência em tal aumento. / In the current days, a big part of the surgical interventions includes the implant of materials. The great obstacles for prosthesis implantation in living organisms are the blood clotting when in contact to the material due to a high level of platelet activation and the biological tissues compatibility to the implanted material. By joining improvements on mechanical properties to biocompatible surfaces, polymer materials present high tendencies to be excellent biomaterials candidates for such applications. The objective of this work was to perform surface modification in polymers through the ion beam implantation method in order to investigate changes induced in their surface properties and study possible biocompatibility changes. Samples of polycarbonate were irradiated with argon ion beam with 23 keV energy and different doses. The surfaces of the samples were analyzed by contact angle measurements, atomic force microscopy, secondary ion mass spectroscopy, x-ray photoelectron spectroscopy, Rutherford backscattering spectroscopy, elastic recoil detection, particle induced x-ray spectroscopy and platelet adhesion tests. The results from the different techniques pointed consistently to a series of chemical and physical changes induced on the samples\' surfaces, such as: significant loss of hydrogen for the irradiated samples, increase of cross-linking between polymer chains which led to the increase of delocalized electrons and color change, removal of additives, migration of argon atoms to the surface and hydrophilicity changes. By comparing all the obtained results to the platelet adhesion tests results, it was found that the observed effects increase the thrombogenic characteristic of the polycarbonate surface and that the removal of additives with sulfate and sulfonate groups after the argon irradiation had great influence on such increase.
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Modificações superficiais em polímeros por feixes iônicos para estudo de biocompatibilidade / Surface modifications in polymers by ion beams for the study of biocompatibilityGustavo Ferraz Trindade 07 October 2013 (has links)
Nos dias atuais, grande parte das intervenções cirúrgicas inclui o implante de materiais. Os grandes obstáculos na implantação de próteses em organismos humanos são a coagulação sanguínea em contato com o material devido ao alto grau de ativação plaquetária e a compatibilidade dos tecidos biológicos ao material implantado. Agregando melhorias de propriedades mecânicas a superfícies biocompatíveis, materiais poliméricos apresentam grandes tendências a serem excelentes candidatos a biomateriais para tais aplicações. O objetivo deste trabalho foi realizar modificações superficiais em polímeros através do método de implantação por feixe iônico a fim de se investigar mudanças induzidas em suas propriedades superficiais e estudar possíveis mudanças em sua biocompatibilidade, em específico, sua hemocompatibilidade. Amostras de policarbonato foram irradiadas com feixes de íons de argônio com energia 23 keV e cinco diferentes doses. As superfícies das amostras foram analisadas com medidas de ângulo de contato, microscopia de força atômica, espectroscopia de massa de íons secundários, espectroscopia de fotoelétrons, espectroscopia de retroespalhamento Rutherford, deteção de recuo elástico, espectroscopia de raios-X induzidos por partículas e testes de adesão plaquetária. Os resultados das diferentes técnicas apontaram de forma consistente a uma série de alterações químicas e físicas induzidas nas superfícies das amostras, dentre elas: a perda significativa de hidrogênio nas amostras irradiadas, aumento do grau de reticulação entre as cadeias poliméricas que levou ao aumento de elétron deslocalizados e mudança de coloração, remoção de aditivos, migração à superfície de átomos de argônio implantados e alteração de hidrofilicidade. Ao confrontar todos os resultados obtidos com os resultados dos testes de adesão plaquetária, constatou-se que os efeitos observados aumentam o caráter trombogênico da superfície do policarbonato e que a remoção de aditivos com grupos sulfato e sulfonato após irradiação com argônio teve grande influência em tal aumento. / In the current days, a big part of the surgical interventions includes the implant of materials. The great obstacles for prosthesis implantation in living organisms are the blood clotting when in contact to the material due to a high level of platelet activation and the biological tissues compatibility to the implanted material. By joining improvements on mechanical properties to biocompatible surfaces, polymer materials present high tendencies to be excellent biomaterials candidates for such applications. The objective of this work was to perform surface modification in polymers through the ion beam implantation method in order to investigate changes induced in their surface properties and study possible biocompatibility changes. Samples of polycarbonate were irradiated with argon ion beam with 23 keV energy and different doses. The surfaces of the samples were analyzed by contact angle measurements, atomic force microscopy, secondary ion mass spectroscopy, x-ray photoelectron spectroscopy, Rutherford backscattering spectroscopy, elastic recoil detection, particle induced x-ray spectroscopy and platelet adhesion tests. The results from the different techniques pointed consistently to a series of chemical and physical changes induced on the samples\' surfaces, such as: significant loss of hydrogen for the irradiated samples, increase of cross-linking between polymer chains which led to the increase of delocalized electrons and color change, removal of additives, migration of argon atoms to the surface and hydrophilicity changes. By comparing all the obtained results to the platelet adhesion tests results, it was found that the observed effects increase the thrombogenic characteristic of the polycarbonate surface and that the removal of additives with sulfate and sulfonate groups after the argon irradiation had great influence on such increase.
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