Teses / dissertações sobre o tema "Mediated oxidation"
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Škrabalová, Lada. "Hemoglobin-mediated oxidation of marine liposomes". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2012. http://www.nusl.cz/ntk/nusl-216833.
Texto completo da fonteWood, Geoffrey Paul Farra. "Theoretical Investigations of Radical-Mediated Protein Oxidation". Thesis, The University of Sydney, 2006. http://hdl.handle.net/2123/1413.
Texto completo da fonteWood, Geoffrey Paul Farra. "Theoretical Investigations of Radical-Mediated Protein Oxidation". University of Sydney, 2006. http://hdl.handle.net/2123/1413.
Texto completo da fonteThis thesis primarily details the application of high-level ab initio quantum chemistry techniques in order to understand aspects of free-radical mediated protein oxidation. Traditionally, product analysis and electron paramagnetic resonance (EPR) spectroscopy are the primary means for elucidating the chemistry of protein oxidation. However, in experiments involving relatively small proteins reacting with a controlled radical-flux, a vast array of compounds can be produced, which are often difficult to analyse. Quantum chemical techniques on the other hand, can calculate the properties of any particular species directly, without suffering from the problems associated with experiment, such as side-reactions and chain processes. The results presented in this thesis are aimed at elucidating mechanistic details of protein oxidation, which might otherwise be difficult to probe experimentally. Chapter 1 gives an overview of the free-radical hypothesis of disease and ageing. Protein-derived radicals can undergo a variety of reactions, with the particular reaction that occurs depending on numerous aspects. Many types of reactions have been identified through radiolysis experiments of amino acids, and these are detailed in this chapter. In addition, the key reactive species are characterized and their different chemistries explained. Chapter 2 details the theoretical tools used throughout this thesis. Species with unpaired electrons (radicals) present unique problems for quantum chemistry to handle, thus an appropriate choice of theoretical technique is needed. The approach taken in this thesis is to use high-level compound methods, many of which have been directly formulated to give improved results for radical species, to provide benchmark quality results by which other less demanding techniques can be assessed. During the course of this study, it became apparent there was a void in the armoury of tools that could be used for the theoretical chemistry calculations. Chapter 3 details the formulation of a new tool in an attempt to fill this gap. Historically, the formulation of this new procedure came after much of the work in this thesis had been carried out. Thus, for the study of many of the reactions of this thesis the new method has not been used. However, it is most appropriate to place its formulation after summarizing the current status of techniques in common use today. Chapters 4 and 5 detail computations carried out on models of peptides containing backbone carbon- and nitrogen-centered radicals. A number of different theoretical techniques are used in these chapters, ranging from the highly accurate and computationally intensive to the less reliable and less demanding. The highly accurate techniques are used to gauge the accuracy of the other less demanding theoretical techniques so that the latter can be used with confidence in larger systems. Not only is the choice of theoretical technique important but also the judicious choice of model is essential. With this in mind, models are incrementally built until convergence of the particular property of interest is reached. Chapters 6 and 7 detail the calculations of β-scission reactions of alkoxyl radicals, which are a particular class of reaction known to occur on peptide backbones. Alkoxyl radicals are particularly difficult for theory to describe correctly. Therefore, Chapter 6 extensively assesses and then identifies the theoretical methods needed to portray them. Chapter 7 uses the techniques identified in the previous chapter in order to predict how the preference for a particular type of β-scission reaction changes.
Hersey, Michelle. "Oxidation of Arsenite Via Chelator-mediated Fenton Systems". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/HerseyMX2006.pdf.
Texto completo da fonteProbert, Gareth David. "The zirconocene-mediated synthesis of amines". Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242623.
Texto completo da fonteHenderson, William Howell. "Palladium-Mediated C-H Activations". The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1318003095.
Texto completo da fonteWright, Adam. "Investigations of singlet oxygen-mediated amino acid, peptide and protein oxidation". Thesis, The University of Sydney, 2002. https://hdl.handle.net/2123/27830.
Texto completo da fonteCrosby, Natasha M. "The role of oxidation in hyperglycemia-mediated erythrocyte phospholipid asymmetry". [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3344761.
Texto completo da fonteTitle from PDF t.p. (viewed Oct. 8, 2009). Source: Dissertation Abstracts International, Volume: 70-02, Section: B, page: 0830. Adviser: David L. Daleke.
Kapinga, Sarah Kasangana. "Organic binder mediated Co3O4/TiO2 heterojunction formation for heterogeneous activation of Peroxymonosulfate". Thesis, Cape Peninsula University of Technology, 2019. http://hdl.handle.net/20.500.11838/2811.
Texto completo da fonteA shortage of water has resulted in the need to enhance the quality of wastewater that is released into the environment. The advanced oxidation process (AOP) using heterogeneous catalysis is a promising treatment process for the management of wastewater containing recalcitrant pollutants as compared to conventional processes. As AOP is a reliable wastewater treatment process, it is expected to be a sustainable answer to the shortage of clean water. AOP using heterogeneous catalysis based on Co3O4 particles and PMS, in particular has been found to be a powerful procedure for the degradation and mineralization of recalcitrant organic contaminants. In addition, due to the growing application of Co3O4 in lithium batteries, large quantities of these particles will be recovered as waste from spent lithium batteries, so there is a need to find a use for them. Although this method has received some promising feedback, challenges still need to be addressed, such as the toxicity of cobalt particles, the poor chemical and thermal stability and particle aggregation, and the prompting of lower catalytic efficiency in long haul application. Furthermore, the removal of the catalyst after the treatment of pollutants is also an issue. In order to be applicable, a novel catalyst must be produced requiring the combination of Co3O4 with a support material in order to inhibit cobalt leaching and generate better particle stability. From the available literature, TiO2 was found to be the best support material because it not only provides a large surface area for well dispersed Co3O4, but it also forms strong Co-O-Ti bonds which greatly reduced cobalt leaching as compared to other support materials. Moreover, it also greatly encourages the formation of surface Co–OH complexes, which is considered a crucial step for PMS activation. Therefore, the issues cited above could be avoided by producing a Co3O4/TiO2 heterojunction catalyst.
Han, Hyungjin Civil & Environmental Engineering Faculty of Engineering UNSW. "Mechanisms and modelling of sonochemically-mediated free radical degradation of contaminants". Awarded by:University of New South Wales. Civil & Environmental Engineering, 2009. http://handle.unsw.edu.au/1959.4/43485.
Texto completo da fonteKristinova, Vera. "Oxidation of marine lipids in liposomes and emulsions mediated by iron and methemoglobin". Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bioteknologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25022.
Texto completo da fonteMulder, Ashley Jade. "The Surface Oxidation States of Copper Nanoparticles Generated by Ligand-Mediated Laser Ablation". Thesis, Curtin University, 2017. http://hdl.handle.net/20.500.11937/59636.
Texto completo da fonteMARTINOVITY, FERENC. "Coupling of soot oxidation and ammonia-mediated selective catalytic reduction of nitrogen oxides". Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2907024.
Texto completo da fonteBotfield, Andrew Civil & Environmental Engineering Faculty of Engineering UNSW. "Kinetic modelling studies of As(III) oxidation in dark pH 3 and 8 Fenton - mediated and pH 8 Cu(II) - H2O2 systems". Awarded by:University of New South Wales. School of Civil and Environmental Engineering, 2006. http://handle.unsw.edu.au/1959.4/31969.
Texto completo da fonteLycksam, Jonas. "Metal Mobilization in Mine Waste as a Result of Oxidation and Bacterial Mediated Activity". Thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-95210.
Texto completo da fonteTobler, Nicole Béatrice. "Iron-mediated coupling of microbial oxidation and abiotic reduction of organic contaminants in anoxic environments /". Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17155.
Texto completo da fonteVahedi, Hooshang. "Catalytic symmetric oxidation of sulfides to sulfoxides mediated by 3-substituted-1,2-benzisothiazole 1,1-dioxides". Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367257.
Texto completo da fonteLippert, Cameron A. "Redox-active ligand-mediated radical coupling reactions at high-valent oxorhenium complexes: reactions relevant to water oxidation for artificial photosynthesis". Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41199.
Texto completo da fonteZhang, Lei 1970. "Sol-gel matrix-mediated synthesis of superparamagnetic iron oxide clusters and supported iron porphyrin oxidation catalysts". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9968.
Texto completo da fonteFirth, Carole Anne. "7,8-Dihydroneopterin-mediated protection of low density lipoprotein, but not human macrophages, from oxidative stress". Thesis, University of Canterbury. Biological Sciences, 2006. http://hdl.handle.net/10092/1317.
Texto completo da fonteGladman, Calvin. "Ferricyanide Mediated Microbial Respiration - Application to the Analysis of Waters and Wastewaters". Thesis, Griffith University, 2011. http://hdl.handle.net/10072/367669.
Texto completo da fonteThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
Full Text
Wang, Jin. "A mechanistic study of the preferential photo-oxidation of the 5-CH3 substituent of thymine and thymidine mediated by NH4(VO(O2)2(5-NO2phen))". HKBU Institutional Repository, 2009. http://repository.hkbu.edu.hk/etd_ra/1056.
Texto completo da fonteDang, Zheng. "The Investigation of Carboxyl Groups of Pulp Fibers during Kraft Pulping, Alkaline Peroxide Bleaching, and TEMPO-mediated Oxidation". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16143.
Texto completo da fonteSopaci, Saziye Betul. "Microorganism Mediated Stereoselective Bio-oxidation And Bio-hydrogenation Reactions And Thiamine Pyrophosphate Dependent Enzyme Catalyzed Enantioselective Acyloin Reactions". Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610516/index.pdf.
Texto completo da fonte90% yield) confirming the suggested mechanism of oxidation-reduction sequence of hydrobenzoin. Wieland-Miescher ketone (3,4,8,8a-tetrahydro-8a-methylnaphthalene-1,6(2H,7H)-dione) is an important starting material for bioactive compounds like steroids and terpenoids. Many synthetic approaches include enantioselective reduction of this compound. In this study Aspergillus niger (MAM 200909) mediated reduction of Wieland-Miescher ketone was achieved with a high yield (80%), de (79%) and ee (94%) value and these results were found much more superior than previously reported studies. Carboligating enzymes benzaldehyde lyase (BAL) (EC 4.1.2.38) and benzoiyl formate decarboxilase (BFD) (E.C. 4.1.1.7) are used for biocatalytic acyloin synthesis. These enzymes are immobilized to surface modified superparamagnetic silica coated nanoparticles by using metal ion affinity technique. With this system recombinant histidine tagged BAL and BFD purified and immobilized to magnetic particles by one-pot purification-immobilization procedure. SDS page analysis showed that our surface modified magnetic particles were eligible for specific binding of histidine tagged proteins. Conventional BAL and BFD catalyzed benzoin condenzation reactions and some representative acyloin reactions were performed with this system with a high enantioselectivity (99-92%) and yield. Results obtained with magnetic particle-enzyme system were also found comparable with that of free enzyme catalyzed reactions.
Diering, Simon [Verfasser], e Friederike [Akademischer Betreuer] Cuello. "The impact of protein oxidation on kinase-mediated phosphorylation and cardiac myocyte contractile function / Simon Diering ; Betreuer: Friederike Cuello". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1182537863/34.
Texto completo da fonteSalem, Mohamed M. A. "H2O2-mediated oxidation and nitration enhances DNA binding capacity / DNA repair via up-regulated epidermal wild-type p53 in vitiligo". Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/3348.
Texto completo da fonteEgyptian government; Institute for Pigmentary Disorders in association with the EM Arndt University of Greifswald, Germany.
Li, Qing Qing. "Nanocellulose: Preparation, Characterization, Supramolecular Modeling, and its Life Cycle Assessment". Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/49556.
Texto completo da fontePh. D.
Aybey, Ayse. "Oxidative Ring Opening Reactions Of A-hydroxy Ketones". Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609279/index.pdf.
Texto completo da fonteSalem, Mohamed Metwalli AbouElloof. "H₂O₂-mediated oxidation and nitration enhances DNA binding capacity/DNA repair via up-regulated epidermal wild-type p53 in vitiligo". Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/3348.
Texto completo da fonteCarlsson, Daniel O. "Structural and Electrochemical Properties of Functionalized Nanocellulose Materials and Their Biocompatibility". Doctoral thesis, Uppsala universitet, Nanoteknologi och funktionella material, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-215090.
Texto completo da fonteSalsman, Scott J. "Redox regulation of protein tyrosine phosphatases in cell membrane receptor-mediated signal transduction". Oklahoma City : [s.n.], 2005.
Encontre o texto completo da fonteSenocak, Deniz. "Chemoenzymatic Synthesis Of Chiral Hydroxymethyl Cycloalkenols". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605056/index.pdf.
Texto completo da fonteMaher, Christopher John. "Options for treatment of legacy and advanced nuclear fuels". Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/options-for-treatment-of-legacy-and-advanced-nuclear-fuels(984fa9e5-3732-4f1b-b9b1-42457ef0f732).html.
Texto completo da fonteSilvers, Kimberly Jane. "The role of cytochrome P450-mediated C-oxidation and cytosolic nitroreduction in the metabolism, DNA binding, and mutagenicity of 1-nitropyrene in human liver". Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1062512189.
Texto completo da fonteOffenbacher, Adam R. "Protein structural changes and tyrosyl radical-mediated electron transfer reactions in ribonucleotide reductase and model compounds". Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39473.
Texto completo da fonteFilosa, Angelo. "Study of locally unfolded forms of cytochrome c by Fourier transform infrared and of H2O2-mediated oxidation of ferricytochrome c and metmyoglobin by mass spectrometry". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ63979.pdf.
Texto completo da fonteKose, Elif. "Chemoenzymatic Synthesis Of 4-hydroxy Enones". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/1252519/index.pdf.
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Aher, Ashish. "SYNTHESIS, CHARACTERIZATION AND APPLICATIONS OF REDUCED GRAPHENE OXIDE AND COMPOSITE MEMBRANES FOR SELECTIVE SEPARATIONS AND REMOVAL OF ORGANIC CONTAMINANTS". UKnowledge, 2019. https://uknowledge.uky.edu/cme_etds/111.
Texto completo da fonteMai, Trang. "FUNCTIONALIZATION OF IRON OXIDE NANOPARTICLES AND THE IMPACT ON SURFACE REACTIVE OXYGEN SPECIES GENERATION FOR POTENTIAL BIOMEDICAL AND ENVIRONMENTAL APPLICATIONS". UKnowledge, 2019. https://uknowledge.uky.edu/cme_etds/102.
Texto completo da fonteDavidson, Stuart Cameron. "The development of organic peroxide mediated oxidations". Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=30330.
Texto completo da fonteOhleier, Alexia. "Nickel mediated negishi and oxidative couplings". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30074/document.
Texto completo da fonteThe aim of this research project is to promote the formation of new C-C bonds and the production of valuable chemicals by using chelated nickel complexes. The first part of this thesis is dedicated to [nickel(bis-phosphine)] complexes employed as catalysts for Negishi cross coupling reactions. Designed Ni(0) precatalyst [(dcpp)Ni(n2-toluene)] (dcpp = 1,3-bis(dicyclohexylphosphino)propane) promotes efficiently the Negishi cross coupling between aryl chlorides and phenylzinc chloride derivatives at low catalyst loadings (down to 0.2 mol% - 1 mol%) under mild conditions (THF, 60°C). Mechanistic investigations relying on stoichiometric reactions and DFT calculations prove the involvement of Ni(0)/Ni(II) intermediates rather than Ni(I)/Ni(III) species during the catalysis. The second part of this work deals with the oxidative coupling between ethylene and CO2 at bis-phosphine and bis-NHC chelated nickel complexes for the production of value-added chemicals. The equilibrium between [(dcpp)Ni(C2H4)] and [(dcpp)nickelalactone] has been investigated by kinetic studies. The subsequent cleavage of [(dcpp) nickelalactone] by pinacolborane leads to its reductive functionalization into a propanol derivative. Preliminary mechanistic and catalytic investigations have been undertaken. Moreover, new methodologies are provided for the synthesis of the first [(bis-NHC)Ni(C2H4)] and [(bis-NHC)nickelalactone] complexes
Grocock, Estella Louise. "Novel catalysts and mechanistic investigation in dioxirane-mediated oxidations". Thesis, Loughborough University, 2000. https://dspace.lboro.ac.uk/2134/33767.
Texto completo da fonteGodinho, Diana Anacleto. "Produção de nanocelulose para aplicação em papel de impressão e escrita". Master's thesis, [s.n.], 2017. http://hdl.handle.net/10316/83161.
Texto completo da fonteA presente tese de mestrado tem como principal objetivo a produção de nanocelulose 1 a partir de pasta kraft branqueada de eucalipto, para aplicação na matriz fibrosa do papel de impressão e escrita e posterior estudo da sua influência nas propriedades papeleiras. A “Indústria Papeleira” ao longo dos últimos anos tem vindo a otimizar o processo de produção de papel face ao aumento da competitividade, abrindo assim portas à investigação de novos materiais, com o objetivo de melhorar as propriedades finais do papel. Neste contexto, sabe-se que o carbonato de cálcio precipitado é um aditivo de extrema importância na sua produção, que para além de ser mais económico do que as fibras de celulose, a sua aplicação melhora substancialmente as propriedades óticas. Desta forma, seria importante aumentar a quantidade percentual deste aditivo na estrutura do papel sem comprometer as propriedades mecânicas. Nesta perspetiva, a área de Nanotecnologia surge como uma via promissora, através da incorporação de nanocelulose na matriz fibrosa do papel, que de certa forma poderá influenciar positivamente os custos de produção. A nanocelulose tem despertado interesse devido às suas propriedades promissoras como, biodisponibilidade da matéria-prima, biodegradabilidade, biocompatibilidade, resistência mecânica, fibrilas com razão comprimento/largura elevada e boas propriedades barreira, promovendo desta forma a sua aplicação como material de reforço em várias áreas, como por exemplo, as áreas têxtil, eletrónica ou alimentar, sendo que na área da produção de papel ainda se encontra numa fase muito preliminar. Neste trabalho produziram-se nanocelulose/microcelulose com características químicas e físicas distintas, mediante aplicação de diferentes pré-tratamentos, com posterior aplicação de tratamento mecânico num homogeneizador de alta pressão, sendo esta metodologia denominada método combinado. Diferentes intensidades foram aplicadas nos pré-tratamentos químicos (oxidação mediada por TEMPO e reação de carboximetilação), e no pré-tratamento enzimático (hidrólise enzimática), enquanto que o tratamento mecânico se manteve constante a energia aplicada. Através da variação das quantidades de hipoclorito de sódio na oxidação mediada por TEMPO, hidróxido de sódio e ácido monocloroacético na reação de carboximetilação e de enzima na reação de hidrólise enzimática, foi possível produzir diferentes amostras, que foram posteriormente caracterizadas para avaliação da influência dos diferentes pré-tratamentos. A caracterização das CNF/CMF obtidas foi fundamental para avaliar a eficiência dos prétratamentos, e a influência destes no tratamento mecânico, especialmente no rendimento global de operação. As folhas laboratoriais foram produzidas com pasta kraft branqueada de eucalipto, amido e Anidrido Alquenil Succínico como agentes de colagem, PCC como filler, poliacrilamida catiónica (CPAM) como agente de retenção e as diferentes CNF/CMF produzidas. Avaliou-se por último a influência da incorporação das CNF/CMF na matriz fibrosa das folhas através da realização de testes físico-mecânicos. Concluiu-se que as CNF produzidas por oxidação mediada por TEMPO e carboximetilação, podem ser usadas como material de reforço na matriz fibrosa do papel e como aditivo no processo de floculação do PCC, promovendo, no geral, melhores propriedades mecânicas e o aumento de cargas minerais no papel. Todavia, o pré-tratamento químico não pode ser demasiado intenso, visto que prejudica a floculação das cargas. Neste estudo, verificou-se ainda em alguns casos, que a poliacrilamida catiónica prejudica as ligações das CNF às fibras. Por esta razão, estudou-se o efeito da eliminação do agente de retenção do furnish, constatando-se que esta ação promove bons resultados nas folhas com CNF produzidas a partir da aplicação de pré-tratamentos químicos (oxidação mediada por TEMPO e carboximetilação), não acontecendo, porém, o mesmo nas folhas com as CMF obtidas através da aplicação do prétratamento enzimático.1-Entendida neste estudo como fibrilas que maioritariamente têm diâmetros até 10 nm, mas que podem apresentar diâmetros superiores, podendo neste caso ser designadas por celulose microfibrilada (CMF).
This dissertation presents a study of nanocellulose 2 production from bleached kraft pulp, obtained from the eucalyptus, and its influence in paper properties when applied on printing and writing. During the past years, the competitivity in papermaking industries has been increased. Consequently, to improve paper properties, papermaking processes used are being optimized creating new horizons to investigate new materials that will refine the paper grades. Precipitated calcium carbon is an extremely important additive in the papermaking. Its application in paper improves substantially the optical properties and it is cheaper than cellulose fibers. Thus, it is important to study how to increase the percentual amount of this additive on the paper matrix without compromise the mechanical properties. In this perspective, the nanotechnology field emerges as a promising area, since the incorporation of nanocellulose on the fibrous matrix can influence positively the production costs. Nanocelluloses has gained much interest due to their promising properties, such as high raw material biodisponibility, biodegradability, biocompatibility, mechanical strength, aspect ratio and good barrier properties, mainly as a reinforcing material in many fields, for example, textile, electronics or medicine. However, the application of CNF in the papermaking industry is in a very preliminary stage. In this work, nanocellulose/microcellulose was produced with different chemical and physical characteristics, by applying different pre-treatments with subsequent application of mechanical treatment in the high-pressure homogenizer (HPH), being this experimental methodology called, combined method. Different intensities are applied in the chemical pre-treatments (TEMPO-mediated oxidation and carboxymethylation reaction), and on enzymatic pretreatment (enzymatic hydrolysis), while the energy applied on mechanical treatment remained constant. Through the variation of the quantities of sodium hypochlorite (TEMPO-mediated oxidation), sodium hydroxide and monochloroacetic acid in the carboxymethylation reaction and also the variation of the enzyme amount in the enzymatic hydrolysis, it was possible to produce different samples that were posteriorly characterized to studied the influence of the pre-treatments. The characterization of the CNF/CMF obtained was crucial to evaluate the efficiency of the pre-treatments, and the influence of these in the mechanical treatment, especially in the overall performance of the operation. The laboratorial sheets were produced with bleached kraft pulp from eucalyptus, starch and alkenyl succinic anhydride as a binder aid, PCC (filler), cationic polyacrylamide (CPAM) as a retention aid, and the different CNF produced. Finally, the incorporation of the CNF/CMF into the fibrous matrix was studied through physical-mechanic tests. It was concluded that the CNF produced by TEMPO-mediated oxidation and carboxymethylation, could be used in the paper fibrous matrix as a reinforcing material and as an additive in the flocculation process of the PCC, promoting the improvement of the mechanical properties and the increasing of the loading material in the sheets. However, the pre-treatment may not be done with too much intensity, since it affects the fillers flocculation. In this study, it was observed in some cases, that cationic polyacrylamide damages the fibresCNF bonding. For this reason, it was also studied the effect of CPAM removal from the furnish and this action, promotes good results in the sheets produced with CNF made from chemical pre-treatments (TEMPO-mediated oxidation and carboxymethylation). Unfortunately, the same does not happened with the sheets that contains CMF produced from enzymatic pre-treatment. 2-In this study, the CNF are understood as fibrils that mostly have diameters up to 10 nm. However, these fibrils may present higher diameters, being in this case called microfibrillated celulose (CMF).
Mansley, Tamsin E. "Iron(III) mediated oxidative cyclisations of substituted cyclopropanes". Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389223.
Texto completo da fonteParry, Joel D. "Transcriptomic assessment of quinone mediated hepatic oxidative stress". Thesis, University of Leicester, 2007. http://hdl.handle.net/2381/30781.
Texto completo da fonteHorne, Susan C. "Free radical mediated oxidative stress in plant cancers". Thesis, Abertay University, 2006. https://rke.abertay.ac.uk/en/studentTheses/fcb5aadb-8ee1-43dd-bbd0-367b93d87d11.
Texto completo da fonteLo, Raquel. "Cystine-mediated oxidative defence in Lactobacillus reuteri BR11". Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/39608/1/Raquel_Lo_Thesis.pdf.
Texto completo da fonteMaheshwari, Himanshu. "Functional 1D mesochannels for Electrochemical Sensors". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0267.
Texto completo da fonteIn this thesis, we discuss vertically oriented mesoporous silica and their characteristic properties, synthesis procedures and applications. It is of particular interest as it provides direct access to underlying substrate through the pores and is suitable for a variety of applications such as molecular sieving, electrode protection, enhanced detection of cations through electrochemistry and electrochemiluminescence, deposition of isolated metallic and polymeric nanowires, DNA biosensor, etc. We then discuss the electrochemically mediated oxidation of natural aminothiols (cysteine, glutathione and homocysteine) by a ferrocene derivative following an EC’ mechanism and the rate kinetics at a bare indium-tin oxide (ITO) electrode. Further, mesoporous silica thin films exhibiting vertical nanochannels were grown by electrochemically assisted self-assembly method onto ITO electrode. When using the silica film deposited electrodes and ferrocenedimethanol (Fc(MeOH)2) as mediator in solution, both cysteine and glutathione can be oxidized by Fc(MeOH)2+ generated at the electrode surface, following an EC’ mechanism. Electron transfer rates were three times faster with cysteine than glutathione, suggesting that selectivity for cysteine could be achieved using mesoporous films. This was exploited for the reagent-free selective detection of cysteine over glutathione by using a ferrocene-functionalized mesoporous silica film on ITO electrode, based on a combination of charge transfer kinetic and mass transport limitations through the oriented nanochannels. This has been demonstrated by cyclic voltammetry and amperometry in a flow injection analysis mode. Experimentally, the lowest concentration of cysteine detected was 3 µM in flow injection analysis mode. Further, microelectrodes made of ITO and carbon were fabricated and modified with mesoporous silica. Carbon microelectrodes were further functionalized with ferrocene and characterized electrochemically. Overall, silica modified electrodes show a good potential in electroanalytical applications for a variety of reagents through their size and charge selective properties
Jain, Nikita. "Chiral hypervalent iodine mediated enantioselective oxidative dearomatization of naphthols". Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62521.
Texto completo da fonteScience, Faculty of
Chemistry, Department of
Graduate
Hulcoop, David Geoffrey. "Manganese(III) acetate mediated domino oxidative free radical cyclisations". Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613805.
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