Дисертації з теми "Failure of UV irradiation"
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Canitez, Nazife. "Pasteurization of Apple Cider with UV Irradiation." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/CanitezN2002.pdf.
Повний текст джерелаYu, Cunjing. "Modulation of immune responses by UV irradiation." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/22813.
Повний текст джерелаSalerni, Ronie. "Continuous UV irradiation process for producing low-creep polyethylene." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ45468.pdf.
Повний текст джерелаKokkonen, E. (Esko). "Fragmentation of small molecules by UV and X-ray irradiation." Doctoral thesis, University of Oulu, 2017. http://urn.fi/urn:isbn:9789526216317.
Повний текст джерелаChen, Xi. "Noble metal photocatalysts under visible light and UV light irradiation." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/47008/1/Xi_Chen_Thesis.pdf.
Повний текст джерелаArmstrong, Graham N. "Laser sterilisation of bacterial and fungal spores." Thesis, University of Glasgow, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288931.
Повний текст джерелаKaplan, Jefferson Coker. "Effect of UV irradiation on properties of hot pressed aluminum nitride." Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/19480.
Повний текст джерелаGrigonis, A., A. Micko, A. Medvid, R. Zabels, Z. Rutkuniene, and V. Vinciunaite. "IR, VIS, and UV laser light irradiation of amorphous carbon films." Thesis, Видавництво СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/20640.
Повний текст джерелаVerma, Meera Mary. "On the effect of UV-irradiation on DNA replication in Escherichia coli." Title page, contents and summary only, 1985. http://web4.library.adelaide.edu.au/theses/09PH/09phv522.pdf.
Повний текст джерелаBao, Yiping. "Investigation of the mechanisms by which UV irradiation activates the tyrosinase gene." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366716.
Повний текст джерелаCatilaz-Simonin, Laurence. "Conception, mise au point, propriétés, d'un revêtement pigmenté polymérisable sous irradiation UV-visible." Mulhouse, 1992. http://www.theses.fr/1992MULH0253.
Повний текст джерелаDas, Lopamudra. "Surface Modification of Synthetic and Natural Polymers using Deep Uv (172 Nm) Irradiation." W&M ScholarWorks, 2017. https://scholarworks.wm.edu/etd/1530192366.
Повний текст джерелаWu, Yanyun [Verfasser], and Jürgen [Akademischer Betreuer] Geis-Gerstorfer. "Photocatalytic antibacterial effects on TiO2-anatase upon UV-A and UV-A/VIS threshold irradiation / Yanyun Wu ; Betreuer: Jürgen Geis-Gerstorfer." Tübingen : Universitätsbibliothek Tübingen, 2017. http://d-nb.info/1199615080/34.
Повний текст джерелаNghiem, Mai Phuong. "Mécanismes physico-chimiques des modifications de contaminants moléculaires sous irradiation UV-V sur satellites." Toulouse, ISAE, 2010. http://www.theses.fr/2010ESAE0004.
Повний текст джерелаElzaouk-Bouilhet, Brigitte. "Etude cinétique de la polymérisation de monomères multifonctionnels par irradiation UV, visible ou laser." Mulhouse, 1993. http://www.theses.fr/1993MULH0293.
Повний текст джерелаTámara, Florez Juan Carlos [Verfasser], and Guido [Akademischer Betreuer] Kickelbick. "Deposition of metallic copper through UV light irradiation / Juan Carlos Támara Florez ; Betreuer: Guido Kickelbick." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2017. http://d-nb.info/1152094505/34.
Повний текст джерелаTámara, Florez Juan Carlos Verfasser], and Guido [Akademischer Betreuer] [Kickelbick. "Deposition of metallic copper through UV light irradiation / Juan Carlos Támara Florez ; Betreuer: Guido Kickelbick." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:291-scidok-ds-269044.
Повний текст джерелаBissagou, Koumba Gaelle. "Fragmentations chimique et physique de plastiques et microplastiques en eau douce sous irradiation UV-visible." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC016/document.
Повний текст джерелаThe question of marine litter and their environmental impact gains importance. It was shown that 80% of plastics results from terrestrial sources, while 20% come from coastlines and seas. Many authors point to a serious environmental problem involved to the absorption of POPs (persistent organic pollutants) by plastic detritus, thus initiating a potential source of contamination of the food chain. All authors attribute the fragmentation to "microplastic" (size < 5mm) to phenomena related to degradation, under UV without ever having demonstrated or analysed it. The rivers constituting then a privileged vector of transport of the terrestrial waste towards the seas and oceans, we decided to highlight (and quantify) the presence of microplastics in a river known as "wild" as the Allier. At the laboratory, we develop simulation protocols for the fragmentation of plastics under UV irradiation of various plastic materials in fresh water. We analyse both the chemical molecules resulting from the degradation of plastics and transferred to the aqueous medium as well as the molecular changes that can undergo the material
Matak, Kristen. "Effects of UV Irradiation on the Reduction of Bacterial Pathogens and Chemical Indicators of Milk." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/29852.
Повний текст джерелаPh. D.
Soontrapa, Kitipong. "Prostaglandin E2-prostaglandin E receptor subtype 4 (EP4) signaling mediates UV irradiation-induced systemic immunosuppression." Kyoto University, 2013. http://hdl.handle.net/2433/170077.
Повний текст джерелаWang, Zhenyu J. "A Study of Denitrosation of N-Nitroso Compounds by Irradiation with Long-Wavelength UV Light." DigitalCommons@USU, 1989. https://digitalcommons.usu.edu/etd/7183.
Повний текст джерелаQuinet, De Andrade Annabel. "Implication de l'ADN polymérase eta dans la réponse aux dommages de l'ADN dans des cellules déficientes en réparation par excision de nucléotides." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00779419.
Повний текст джерелаAdedapo, Remilekun. "Disinfection By-Product Formation in Drinking Water Treated with Chlorine Following UV Photolysis & UV/H2O2." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/919.
Повний текст джерелаDev, Kumar Govindaraj. "Effect of Ozone and Ultraviolet Irradiation Treatments on Listeria monocytogenes Populations in Chill Brines." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/35954.
Повний текст джерелаMaster of Science in Life Sciences
Renaudie, Laëtitia. "Modification de surface de film et de fibres de polytéréphtalate d'éthylène par greffage d'oligosaccharides en vue d'une application en filtration sanguine." Paris 11, 2004. http://www.theses.fr/2004PA112143.
Повний текст джерелаThe objective of the present work is to improve the leukocyte retention ability of pet fibers, constituent in standard deleukocytation filters, by grafting carbohydrates with an affinity to white blood cells. Sialyl lewis x carbohydrates are known to be good ligands for some proteins present on leukocytes surface, the l-selectins. In this way, grafting of a sialyl lewis x carbohydrate on the pet surface should lead to a more selective leukocyte retention during human blood filtration. In this perspective, we have been interested in carrying out grafting models with less elaborate carbohydrates and more exactly with lactose-based carbohydrates to determine optimal grafting conditions. The first considered strategy, a grafting by copolymerization between pet fibers, acrylamide monomers and lactose-based monomers has not led to satisfying results. Grafting of a uv-reactive lactose-based carbohydrate has been then carried out on pet film by a simple deposite of a solution of the photoreactive molecule and on pet fibers by dip-coating. By this uv-grafting method, a quantitative grafting on fibers and a near-quantitative grafting on film were obtained. At least, we have been interested in synthesizing a uv-reactive sialyl lewis x hexasaccharide. Unfortunately, at the last step of the synthesis, the final product has not been pure isolated and consequently, uv-grafting and biological tests of deleukocytation have not been performed
Cario-Andre, Muriel. "Rôle des mélanocytes dans l'unité épidermique de mélanisation reconstruite ex-vivo après une irradiation UV aiguë." Phd thesis, Université Victor Segalen - Bordeaux II, 2000. http://tel.archives-ouvertes.fr/tel-00194194.
Повний текст джерелаCario-André, Muriel. "Rôle des mélanocytes dans l'unité épidermique de mélanisation reconstruite ex-vivo après une irradiation UV aiguë." Bordeaux 2, 2000. https://tel.archives-ouvertes.fr/tel-00194194.
Повний текст джерелаMaldonado, Alvarado Pedro Gustavo. "Facteurs déterminants du pouvoir de panification de l’amidon de manioc modifié par fermentation et irradiation UV." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20004/document.
Повний текст джерелаThe breadmaking ability of sour cassava starch, cassava starch modified by fermentation and UV irradiation, have not been yet fully elucidated. The influence of genotype and postharvest treatments on expansion ability of sour cassava was the objective of this work. Thirteen cassava genotypes have been studied. All genotypes proceeded from Colombia. Two altitudes of origin (1000 m. and 1700 m.a.s.l. refered to respectively as lowland and highland), fermentation treatments (0 or 30 days) and drying treatments (oven or sun) were considered. Analyses of the granule size, RVA pasting behavior and intrinsic viscosity were analysed as indicators of breadmaking ability. Results showed that post-harvest treatments were prevailing factors in improving breadmaking ability while the genotype factors had a smaller influence. Among post-harvest treatments, fermentation had a greater influence than sun-drying on these indicators, in particular on starch granular structure. The combination of both treatments was needed to obtain a high capacity bread. Furthermore, the altitude of origin of cassava genotypes was observed to affect the fermentation process: different sensitivities to fermentation were found between granules of lowland and highland (exocorrosion and endocorrosion, respectively). Highland genotypes showed a better breadmaking ability. Other influencing factor related to genotype was the amylose content measured by DSC: it negatively influenced the expansion of the dough, probably due to the formation of amylose-lipid complex. As a conclusion, the combination of cassava genotypes (mainly amylose content) and post-harvest treatment is key for expansion ability of sour starch. This knowledge is a first, essential step to provide quality standards for sour starch, targeted particularly for use in gluten-free products
Planes, Mikael. "Amélioration de la stabilité du polydiméthylsiloxane en environnement géostationnaire." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0176/document.
Повний текст джерелаThe geostationary environment around Earth is complex which strongly influences the satellites performances and lifetime. In flight and over time, polydimethylsiloxanes exhibit degradations like a loss of flexibility and transparency, or a deterioration of the surface state. In this context, the aim of this work was to study the evolution of polydimethylsiloxanes stability in geostationary environment to find solutions to limit the degradation of interest technological properties, in particular the optical one. The stabilization of silicone resins under UV irradiation has been performed by the incorporation of different additives such as Hindered Amine Light Stabilizers, UV Absorbers and cellulose nanocrystals into the PDMS matrix. Generally, polydimethylsiloxanes networks are obtained by hydrosilylation with highly active Karstedt catalyst. Various organometallics derivatives based on Rhodium and Platinum were studied as alternative catalysts for the cross-linking of polydimethylsiloxane in order to improve the UV stability. Finally, different solutions concerning the stabilization of polydimethylsiloxane to proton irradiation, such as the addition of various additives like polystyrene or silsesquioxanes have been investigated
Ho, Chiu Man. "Repression of photoreactivation and dark repair of coliform bacteria by TiO[subscript 2]-modified UV-C irradiation /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202009%20HO.
Повний текст джерелаChevremont, Anne-Celine. "Optimisation multivariée d’un traitement des eaux usées par DEL-UV en vue d’une réutilisation pour l’irrigation Multivariate optimization of fecal bioindicator inactivation by coupling UV-A and UV-C LEDs Effect of coupled UV-A and UV-C LEDs on both microbiological and chemical pollution of urban wastewaters Impact of watering with UV-LED-treated wastewater on microbial and physico-chemical parameters of soil Fate of carbamazepine and anthracene in soils watered with UV-LED treated wastewaters." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4735.
Повний текст джерелаThe development of new technologies for wastewater reuse is a priority for arid and semi-arid areas such as Mediterranean countries. The objective of this work was, firstly, to develop a system for tertiary treatment of wastewaters testing LEDs emitting UV-A and / or UV-C (UV LEDs) on fecal indicator inactivation (Escherichia coli and Enterococcus faecalis) and then on urban effluents, by studying the decrease in both microbial and chemical pollution. This first step has highlighted a higher efficiency of this system when UV UV-A and UV-C are coupled. Wasterwaters with quality meeting the statutory requirements for the reuse of wastewater for irrigation were obtained and used in the second part of this work was to study the impact of watering with UV-LED- treated wastewaters on soil parameters and on the fate of pollutants (anthracene and carbamazepine) in soils. Watering with UV-LED treated wastewater does not change the chemical composition of soil organic matter, the global catabolic activity of soil microorganisms, and the number and diversity of fecal indicators compared to control (irrigation water). Certain enzymatic activities related to the degradation of organic matter increased in soil watered with UV-LED treated wastewater, showing that the organic matter added by the effluent is actively degraded by microorganisms. In addition, aromatic pollutants are oxidized two to three times faster in soils watered with UV-LED treated wastewater
Shen, Hang. "Development of functional biopolymers with controlled architecture." Thesis, Saint-Etienne, 2013. http://www.theses.fr/2013STET4027/document.
Повний текст джерелаHydroxyl telechelic polylactic acids of various molecular weights were synthesized by ring opening polymerization in the presence of LLA and 1,4-butanediol. Telechelic hydroxy polyhydroxybutyrate were prepared transesterification of PHB and 1,4- butanediol catalyzed by p- toluene sulfonic acid. These oligomers were used to prepare polyesteramides functionalised acrylates or mercaptans. In a parallel approach, the PCL multi acrylate was successfully prepared by ring-opening copolymerization of glycidyl methacrylate with caprolactone. Copolymers (GMA-co-CL) with variable molar masses and functionality were prepared by changing the reaction parameters such as catalyst, the nature of the co-initiator and the ratio of different stoichiometric reagents. Multi-acrylated polymers were copolymerized with HEMA under UV irradiation to obtain PLA, PHB and PCL segmented networks. Degradation mechanisms of these networks have been studied by examining particular decomposition of urethane bonds and esters. Depolymerization of the PHEMA was detected with TGA -FTIR at higher temperature (450°C). For PCL based networks, the thermo- mechanical properties were studied. The result shows that the PCL-rich phases have good compatibility with poly HEMA. The rubber and the working temperature range of the damping zones modules can be controlled as a function of reaction parameters. Multi mercapto functionalized polymers with PCL, PLA and PHA segments were used to grow methacrylate polymer chains and build star type
LIU, XIAOXIAO. "UV Laser Treatment of Tire Reinforcing Materials for Improved Adhesion to Rubber." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1445884367.
Повний текст джерелаMostovyi, U. R., Yu V. Rudyk, B. I. Turko, and V. B. Kapustianyk. "Superhydrophobic/superhydrophilic switching on the surface of ZnO microstructures caused by UV irradiation and argon ion etching process." Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/45813.
Повний текст джерелаCheung, Lok Man. "Investigation of virus inactivation and by-products formation under sequential disinfection using UV irradiation and free chlorine/monochloramine /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202004%20CHEUNG.
Повний текст джерелаIncludes bibliographical references (leaves 106-124). Also available in electronic version. Access restricted to campus users.
Hudaya, Tedi Chemical Sciences & Engineering Faculty of Engineering UNSW. "Synthesis, characterisation, and activity of novel TiO2-based photocatalysts for organic pollutant photodestruction under UV and visible-light irradiation." Publisher:University of New South Wales. Chemical Sciences & Engineering, 2008. http://handle.unsw.edu.au/1959.4/42612.
Повний текст джерелаÖstrand, Therese. "Analysis of CHS, MEB5.2, PDX1.3 and PR-5 expression in Arabidopsis thaliana ecotypes during UV-B irradiation." Thesis, Örebro universitet, Akademin för naturvetenskap och teknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-9733.
Повний текст джерелаPigatto, Gisele [UNESP]. "Irradiação UV em Xanthomonas campestris pv. campestris visando a produção da goma xantana." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/94867.
Повний текст джерелаXanthomonas campestris é uma bactéria fitopatogênica que causa a podridão negra no sistema vascular das plantas da família das cruciferaceaes. Produz um exopolissacarídeo denominado goma xantana, que possui propriedades reológicas únicas sendo utilizada amplamente como agente de suspensão, espessante, emulsionante e estabilizante. É aplicados em indústrias petrolíferas, alimentícias, farmacêuticas, mineração, têxtil, termoquímicas, tintas, cosméticos e produtos agropecuários. O Brasil é um grande produtor mundial de cana de açúcar e álcool etílico. Produtos estes utilizados para a produção de xantana; o primeiro como substrato da fermentação e o segundo para a separação da goma. Apesar de todo esse potencial, o Brasil importa grande quantidade de goma xantana que poderá ser produzida com grande competitividade internacional. Portanto, este trabalho objetivou a utilização da técnica de irradiação ultravioleta, em uma linhagem específica de Xanthomonas campestris, para a obtenção de mutantes estáveis que possam melhorar o rendimento e/ou qualidade de goma obtida. A quantificação foi realizada através da determinação da biomassa, viscosidade, cálculos do rendimento da biomassa e goma. A irradiação UV por 600 segundos causou uma redução de 92,2% na população irradiada e as linhagens sobreviventes foram isoladas e analisadas nos testes de produção e viscosidade da goma xantana. As linhagens I6, I7, I9 e I10 apresentaram um aumento de 102% na produção de goma comparando com a linhagem não irradiada. Em relação à viscosidade do caldo, as linhagens irradiadas obtiveram um aumento de 48% comparadas com as não irradiadas de 20 e 30 rpm. A viscosidade da solução de goma xantana 1%, também foram superiores quando comparadas com a não irradiada. O aumento de...
Xanthomonas campestris is fitopatogenic bacterium that causes the black rotten in the vascular system of the plants of the family of the cruciferaceaes. It produces an exopolysaccharides that forms the xanthan gum, which is used in ample variety as agent of suspension, thicker, emulsifier and stabilizing, and singular rheological properties. It is applied in petroliferous, nourishing, pharmaceutical industries, of mining, textile, thermo chemistries, inks, cosmetics and farming products. Brazil is the worldwide producing greater of sugar cane of sugar and ethyl alcohol. Products theses used for the xanthan production; the first one as substratum of the fermentation, and the second as for the separation of the gum. Despite all this potential, the Brazil imports lot of xanthan gum that could be produced with great international competitiveness. This aimming work the used of the ultraviolet technique of irradiation in a specific strain of Xanthomonas campestris to obtain the mutants that can improve the income and/or quality of produced gum, through the determination of the biomass, viscosity, calculations of the income of the biomass and gum. The UV irradiation during 60 seconds caused a reduce of the 92.2% in the irradiated strains and the survived strains were isolated and analysed in the tests of production and viscosity of xanthan gum. The strains I6, I7, I9 e I10 showed increased in the xanthan production of 102% comparing with the non-irradiated strain. In relation the viscosity of the broth the irradiated strains the increase of 48% in shear rate of 20 and 30 rpm compared with the no irrdiated. The viscosity of the xanthan solution 1% irradiated were higher also whwn compared with no irradiated in both shear rate (20 and 30 rpm. The increase of viscosity was of 17% to rotational speed of 20 rpm and 16% to 30 rpm. The ...(Complete abstract click electronic access below)
Guler, Emine. "Two wavelength high intensity irradiation for effective crosslinking of DNA to protein." Link to electronic thesis, 2004. http://www.wpi.edu/Pubs/ETD/Available/etd-0409104-121146.
Повний текст джерелаMaurin, Vanessa. "Revêtements poudres UV : mécanismes de polymérisation et étude des relations structures / propriétés." Thesis, Mulhouse, 2012. http://www.theses.fr/2012MULH4091.
Повний текст джерелаIn the frame of a project of the Agency National Research (France), the thesis deals with the study and the development of UV powder coatings dedicated to wood based panels. The work describes the main features of these formulations and the associated technology in order to offer a strong bibliography specific to this area. The experiments are based on model formulations containing an UV powder resin (diacrylate urethane or dimethacrylate polyester) and a photoinitiator. A mechanistic study allows highlighting the influence of temperature and viscosity, light intensity and atmosphere on the reactivity of the model formulations. It is also shown that the termination mechanisms specific to theses systems follow mixed processes: bimolecular, pseudo-monomolecular and primary radical termination. The predominance of the different processes is related to the reaction conversion. The building of the crosslinking network is then studied depending of the irradiation source: semi-industrial conveyor equipped with UV lamps or LED system emitting around 395 nm. The characteristics of the crosslinking network (Tg, crosslinking density, Young’s modulus) are linked to the final coatings properties (flexibility, scratch and solvent resistance). The incorporation of multifunctional acrylates affects the chains length and crosslinking density. To reach specific applications, it is finally proposed to add a silver-modified clay into model formulations to obtain homogeneous antibacterial UV powder coatings exhibiting good resistance properties
Jagadeesan, Sasi Kumar. "Experimental Approach for Drug Profiling of Calcitriol in Yeast." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34617.
Повний текст джерелаZinina-Izri, Irina Victorovna. "Copolymérisation sous irradiation UV des couples du type accepteur/donneur sans photoamorceur. Rôle du complexe à transfert de charge (CTC)." Montpellier 2, 1998. http://www.theses.fr/1998MON20076.
Повний текст джерелаLewis, Christopher James. "Quantifying the Effects of Aging on the Mechanical Properties of Medical Grade Polycarbonate and UV Cured Adhesives." BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/199.
Повний текст джерелаPigatto, Gisele. "Irradiação UV em Xanthomonas campestris pv. campestris visando a produção da goma xantana /." São José do Rio Preto : [s.n.], 2008. http://hdl.handle.net/11449/94867.
Повний текст джерелаBanca: Valéria Marta Gomes de Lima
Banca: Ivanise Guilherme Branco
Resumo: Xanthomonas campestris é uma bactéria fitopatogênica que causa a podridão negra no sistema vascular das plantas da família das cruciferaceaes. Produz um exopolissacarídeo denominado goma xantana, que possui propriedades reológicas únicas sendo utilizada amplamente como agente de suspensão, espessante, emulsionante e estabilizante. É aplicados em indústrias petrolíferas, alimentícias, farmacêuticas, mineração, têxtil, termoquímicas, tintas, cosméticos e produtos agropecuários. O Brasil é um grande produtor mundial de cana de açúcar e álcool etílico. Produtos estes utilizados para a produção de xantana; o primeiro como substrato da fermentação e o segundo para a separação da goma. Apesar de todo esse potencial, o Brasil importa grande quantidade de goma xantana que poderá ser produzida com grande competitividade internacional. Portanto, este trabalho objetivou a utilização da técnica de irradiação ultravioleta, em uma linhagem específica de Xanthomonas campestris, para a obtenção de mutantes estáveis que possam melhorar o rendimento e/ou qualidade de goma obtida. A quantificação foi realizada através da determinação da biomassa, viscosidade, cálculos do rendimento da biomassa e goma. A irradiação UV por 600 segundos causou uma redução de 92,2% na população irradiada e as linhagens sobreviventes foram isoladas e analisadas nos testes de produção e viscosidade da goma xantana. As linhagens I6, I7, I9 e I10 apresentaram um aumento de 102% na produção de goma comparando com a linhagem não irradiada. Em relação à viscosidade do caldo, as linhagens irradiadas obtiveram um aumento de 48% comparadas com as não irradiadas de 20 e 30 rpm. A viscosidade da solução de goma xantana 1%, também foram superiores quando comparadas com a não irradiada. O aumento de...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Xanthomonas campestris is fitopatogenic bacterium that causes the black rotten in the vascular system of the plants of the family of the cruciferaceaes. It produces an exopolysaccharides that forms the xanthan gum, which is used in ample variety as agent of suspension, thicker, emulsifier and stabilizing, and singular rheological properties. It is applied in petroliferous, nourishing, pharmaceutical industries, of mining, textile, thermo chemistries, inks, cosmetics and farming products. Brazil is the worldwide producing greater of sugar cane of sugar and ethyl alcohol. Products theses used for the xanthan production; the first one as substratum of the fermentation, and the second as for the separation of the gum. Despite all this potential, the Brazil imports lot of xanthan gum that could be produced with great international competitiveness. This aimming work the used of the ultraviolet technique of irradiation in a specific strain of Xanthomonas campestris to obtain the mutants that can improve the income and/or quality of produced gum, through the determination of the biomass, viscosity, calculations of the income of the biomass and gum. The UV irradiation during 60 seconds caused a reduce of the 92.2% in the irradiated strains and the survived strains were isolated and analysed in the tests of production and viscosity of xanthan gum. The strains I6, I7, I9 e I10 showed increased in the xanthan production of 102% comparing with the non-irradiated strain. In relation the viscosity of the broth the irradiated strains the increase of 48% in shear rate of 20 and 30 rpm compared with the no irrdiated. The viscosity of the xanthan solution 1% irradiated were higher also whwn compared with no irradiated in both shear rate (20 and 30 rpm. The increase of viscosity was of 17% to rotational speed of 20 rpm and 16% to 30 rpm. The ...(Complete abstract click electronic access below)
Mestre
Dirckx, Olivier. "Éude du comportement photochimique de l'Abiès grandis sous irradiation solaire." Nancy 1, 1988. http://www.theses.fr/1988NAN10439.
Повний текст джерелаKuck, Luiza Siede. "Microencapsulamento de compostos bioativos da uva (Vitis labrusca L.) e efeito do tratamento pós-colheita com UV-C em uvas Bordô." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/147635.
Повний текст джерелаThe state of Rio Grande do Sul, Brazil, is the greatest producer of grapes in the country. Vitis labrusca cultivars constitute more than 90% of production, underscoring Isabel and Bordô varieties, featuring high concentrations of polyphenols, especially antioxidant anthocyanins used as food coloring. Since the use of the compounds in food is rather difficult due to their unstableness, microencapsulation is one of the methods to protect the compounds from adverse environmental condition. Grape pomace, the residue from the manufacture of juice and wine, has high polyphenol concentration and is mainly formed by grape skin. Current thesis aims at extracting polyphenols from the skin of Isabel and Bordô grape varieties and their micro-encapsulation by different wall materials. Research was divided into three stages. The first stage comprised the separation of phenolic compounds by water extraction in the acid medium of the skin of the Isabel grape variety. The extract was spray-dried for microparticles by means of gum arabic, β-cyclodextrin and hydroxypropyl-β-cyclodextrin as encapsulating agents at maximum 5% concentrations. Powders were assessed for total phenols, total monomer anthocyanins, flavonoids, flavanols, antioxidant activity (DPPH, CUPRAC and HRSA), color, humidity, water activity, solubility, hygroscopicity, glass transition temperature and micro-structure. As a rule, the powders featured high hygroscopicity, low glass transition temperature and particle agglomeration. Treatment with 3% of gum arabic 3% and 2% of β-cyclodextrin was the best, with the highest retention rate of flavonoids (67.2%), flavanols (51.1%), antioxidant activity, and with DDPH (55%) and CUPRAC (58.8%), lowest hygroscopicity (17.33%) and highest glass transition temperature (32.85 °C). In the second stage the acidified water phenolic extract from the Bordô grape skin was spray-dried and freeze-dried for microparticles with gum arabic, partially hydrolyzed guar gum and polydextrose, with a total 10% of wall material. Powders were assessed for total phenols, total monomer anthocyanins, antioxidant activity (DPPH, CUPRAC, HRSA), color, humidity, water activity, solubility, hygroscopicity, glass transition temperature, particle size and micro-structure. High retentions occurred, with more than 80% for total phenols and total monomer anthocyanins; and between 45 and 84% for antioxidant activity in all treatments under analysis. Atomized powders had lower humidity, water activity and particle size, greater solubility, higher glass transition temperature, and better morphological characteristics than the freeze-dried powders. The powder obtain by spray-dried with 5% of partially hydrolyzed guar gum and 5% of polydextrose was the best treatment due to greater retention of total phenols (89.0%), total monomer anthocyanins (99,5%) and antioxidant activity for DPPH (57.3%) and CUPRAC (83.2%). The third stage comprised dispersions of the extract of the Bordô grape skin with partially hydrolyzed guar gum 5% and polydextrose 5%, or rather, the best treatment among those prepared with Isabel and Bordô grapes. Dispersions were spray-dried and freeze-dried to obtain microparticles which underwent fast storage tests (relative humidity rates 75 and 90% at 35, 45 and 55 °C) and gastrointestinal digestion simulations (divided into two phases: gastric and intestinal phases). Total phenols, total monomer anthocyanins and antioxidant activity for ABTS were evaluated. Fast tests revealed that temperature had a significant effect on the decrease in phenol contents, with 82.5 - 93.5% retentions. Temperature, relative humidity and time were significant on the reduction of total monomer anthocyanin contents, with 3.9 – 42.3% retentions. Decrease in total monomer anthocyanin rates revealed a first order kinetics, whilst z and Ea rates indicated highly unstable freeze-dried powder for changes in temperature when higher temperatures are employed. On the other hand, D and t1/2 rates were very close between the two powders, revealing slight stability difference between the two at temperatures employed in current study. Thermodynamic parameters demonstrated an endothermic and non-spontaneous reaction. Antioxidant activity behaved similarly to total phenols with a final retention between 38.5 and 59.5%. In the case of gastrointestinal digestion simulation, the two powders released 80% phenols during the gastric phase and a significant increase in release during the intestinal phase in which spray-dried and freeze-dried powders had 90.6% and 94.9% release during the last hour of the experiment. A similar behavior was detected for antioxidant activity in which spray-dried and freeze-dried powders featured 50% during the gastric phase and a significant increase during the intestinal one, with 69.4% and 67.8% of antioxidant activity respectively by the spray-dried and freeze-dried powders during the last hour of the experiment. However, monomer anthocyanins had a significant 50% reduction of contents in the intestinal phase in which the spray-dried and freeze-dried powders had 39% and 39.8% release respectively during the last hour of the experiment. The methods for obtaining microparticles failed to affect the stability of the powder in fast storage tests and in gastrointestinal simulation tests. Current research also evaluated the effect of UV-C irradiation on Bordô grapes for post-harvest treatment. Two harvests in two different years were analyzed: grapes of the first harvest underwent 0, 0.5, 1, 4, 10 and 30 minutes irradiation (120 W) and stored at 22 °C, whereas grapes of the second harvest underwent UV-C irradiations (120 W) during 0, 0.5 and 4 minutes, coupled to ultrasound (40 kHz) for 5 minutes and stored at 22 °C. The former did not have any increase in bioactive compounds and antioxidant activity. Results of the latter, however, demonstrated a significant increase in total phenols, total monomer anthocyanins and antioxidant activity for grapes irradiated during 0.5 minutes with UV-C and for those irradiated with UV-C for 4 minutes plus ultrasound for 5 minutes. There was 1.2 - 2.0 times increase when compared to control, with no change in color in the irradiated grapes.
Abdul, Halim Nadiya. "Quantitative Fr 13 Failure Modelling of Uv Irradiation for Potable Water Production – Demonstrated with Escherichia Coli." Thesis, 2017. http://hdl.handle.net/2440/119334.
Повний текст джерелаThesis (Ph.D.) -- University of Adelaide, School of Chemical Engineering & Advanced Materials, 2017
Ashby, Sam. "UV-irradiation of fused-biconic-taper fibre couplers." Phd thesis, 2004. http://hdl.handle.net/1885/148659.
Повний текст джерелаWu, TsungChing, and 吳宗璟. "Human DDB2 is Protective against UV-irradiation in Drosophila." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/93119812939457457103.
Повний текст джерела長庚大學
基礎醫學研究所
94
Our previous study demonstrated that human DDB2, a DNA repair protein known to participate in genomic DNA repair of UV damage, is a modulator of UV-induced apoptosis, and that UV resistance can be overcome by inhibition of DDB2 in mammalian cell culture. However, the molecular mechanism underlying the protective role of DDB2 is not fully understood. Fruit fly (Drosophila melagaster) that lacks DDB2 homologue has been used as an animal model for studying numerous protein functions including DNA repair. In previous study, we revealed that hDDB2 could protect fly from UV-irradiation in third-instar larvae, but is not sufficient to attenuate major apoptosis pathways. Here, we demonstrated the protective roles of hDDB2 in UV-irradiated embryo. Using UAS-Gal4 expression system, hDDB2 was absolutely detected in cell nuclei of Drosophila embryo no matter with UV-irradiation or not. In contrast, dDDB1 was diffusely distributed in cells. Following UV-irradiation, however, dDDB1 was concentrated in embryonic nuclei. Moreover, the cyclobutane pyrimidine dimers (CPD) repair assay indicated that the amounts of UV-induced CPD are accumulated in nuclei in a dose-dependent manner; CPD was then gradually removed following repair incubation. From the gel shift assay, hDDB2 also elevated the activity of UV-DDB, the key step in DNA repair ability. Confocal microscopy analysis indicated that hDDB2 co-localizes with CPD in nuclei immediately after UV-irradiation, and also elevates the CPD repair efficiency. Colocalization between hDDB2 and dDDB1 were demonstrated by fluorescent immunolabeling assay. These findings reveal that hDDB2 could protect fly against UV along various developmental stages. These results suggest that heterologous molecules, hDDB2 and dDDB1, may act in concert to participate in DNA repair and provide a possible explanation for UV protection in both cultured cells and organism.
Lan, Hsin-Chieh, and 藍心婕. "Synergistic Apoptosis in CHO.K1 Cells Recovered from UV Irradiation." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/63215899945836244636.
Повний текст джерела國立清華大學
生命科學系
88
Cell death following exposure to genotoxin, for example, ultraviolet, can occur via several routes, including mitotic catastrophe, extended or permanent cell cycle arrest, and apoptosis. Previously, the massive cell death induced by colcemid after UV exposed in CHO.K1 cells has been proved. Colcemid, a mitosis inhibitor, caused the synergistic cell death cooperated with UV damage and this effect was incubation time and drug dose dependent. Upon exposure to 0.5 mg/ml of colcemid after UV 26 j/m2 treatment, cell morphology was severely altered, cell volume decrease, and condensation of the chromosome was clearly noticeable. Besides this, the fragmentation of genomic DNA indicated cell death caused by drug and UV was probably due to apoptosis. To determine if other cell cycle inhibitors would promote cell death in the same situation, mimosine, the G1 phase inhibitor were tested and synergistic apoptosis was observed of this drugs also. Different modes of cell death can occur within individual cell type to the genotoxin, so two different cell lines, NIH3T3 and HF-E6, were treated. The results show that there was no obvious diversity between two data of UV exposed alone and coexist with colcemid. The outcomes of HF-E6 cells that lack of p53 protein functions, indicate the synergistic apoptosis might be not due to p53 disruption. Recent work has suggested that cell cycle inhibitors could induce synergistic apoptosis after UV damage dependents on cell type, medicinal dose and incubation time, but not for dysfunction of p53 protein.