Tesis sobre el tema "Catalyst aging"
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Li, Haitao. "Supercritical carbon dioxide aided preparation of nickel oxide/alumina aerogel catalyst". [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001090.
Texto completoMOROSANU, EDUARD ALEXANDRU. "Catalytic processes for CO2 conversion into Synthetic Methane". Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2841162.
Texto completoKandilli, Nur. "Development Of A Three Way Catalytic Converter For Elimination Of Hydrocarbons, Carbon Monoxide And Nitric Oxide In Automotive Exhaust". Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612546/index.pdf.
Texto completoC and 600 º
C. Gas composition data from massspectrometer and CO analyzer and temperature data from thermocouple at the monolith entrance, are converted to conversion versus temperature graphs. Results of 26 activity tests are compared. Catalyst containing coimpregnated CZO support material with metals, showed the lowest loss of catalytic performance after exposure to SO2 during activity tests. Catalyst containing separately impregnated CZO support material, showed the highest resistance against thermal aging at 900 º
C and 1000 º
C, and even improved catalytic activity after aging. These catalysts showed higher resistances against the applied procedures than the commercial catalyst.
Birgersson, Henrik. "Development and Assessment of Regeneration Methods for Commercial Automotive Three-Way Catalysts". Doctoral thesis, Stockholm, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3931.
Texto completoPanpranot, Joongjai. "Hydrothermal aging of zeolite-based catalysts". Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=274.
Texto completoTitle from document title page. Document formatted into pages; contains xi, 84 p. : ill. Includes abstract. Includes bibliographical references (p. 64-67).
Blades, Luke Aubrey William. "Ageing mechanisms in automotive catalysts". Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.695255.
Texto completoWoods, Andrew John. "Ageing and characterisation of automotive catalysts". Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486263.
Texto completoRachele, Karen Gonçalves. "Estudo de catalisadores modelo à base de CeO2-ZrO2 dopado com cobre para controle de emissões de NOx". Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5048.
Texto completoConvencionalmente, metais nobres são empregados como metais ativos em catalisadores automotivos, mas o uso de cobre vem sendo estudado pelo fato de promover sítios ativos para adsorção química e redução de NOx. Diante deste contexto, esta dissertação visa testar novas formulações de catalisadores, com foco em seu desempenho na reação de redução do NO pelo CO e sua seletividade a N2. Foram avaliados o método de adição de cobre no preparo e os teores de cobre utilizados na preparação. Os métodos de adição utilizados foram impregnação a seco (IS), reação em estado sólido (RS) e coprecipitação (CO). Os teores de cobre estudados ficaram entre 0,36 e 6,9% (m/m). Além disso, foi estudado o impacto no desempenho do catalisador após envelhecimento térmico a 950C por 12h. Foram empregadas as seguintes técnicas de caracterização textural e físico-química como espectrometria de absorção atômica, fisissorção de N2, difração de raios X, espectroscopia Raman e redução a temperatura programada. Os catalisadores também foram avaliados na reação de redução do NO pelo CO. A análise textural indicou que o método de coprecipitação levou a características texturais diferentes dos outros catalisadores. Análises de DRX mostraram a formação de CuO cristalino para teores iguais ou superiores a 3,3% (m/m) de cobre. As análises de Redução a Temperatura Programada (RTP) indicaram que ocorreu uma forte interação na interface entre o suporte e as espécies de cobre dispersas, acompanhada da diminuição da temperatura de redução do CuO e da redução parcial da céria em temperaturas mais baixas. Os testes catalíticos mostraram um melhor desempenho dos catalisadores (IS) que apresentaram conversões mais elevadas em menores temperaturas. Com relação ao envelhecimento, observou-se uma diminuição significativa da eficiência dos catalisadores. Uma comparação com catalisadores à base de metal nobre mostrou um bom desempenho dos catalisadores à base de cobre, com a vantagem destes apresentarem emissão de N2O restrita a baixas temperaturas
Conventionally, noble metals are used as active metals in automotive catalytic converters, but the use of copper has been studied because copper promote active sites for chemical adsorption and reduction of NOx. Thus, this work aims to test new formulations of automotive catalysts, focusing on their performance in catalytic reduction of NO by CO and its selectivity to N2. The method of copper addition and the copper contents used in the preparation were evaluated. The addition methods used were dry impregnation (IS), solid state reaction (RS) and coprecipitation (CO). The copper contents studied were between 0,36 e 6,9 wt%. In addition, the impact on catalyst performance after thermal aging at 950 C for 12h was also studied. Textural and physico-chemical caracterization techniques were employed, such as atomic absorption spectrometry, N2 physisorption, X-ray diffraction, Raman spectroscopy and temperature programmed reduction. Catalysts were evaluated in the reduction reaction of NO by CO. The textural analysis indicated that addition of copper by the coprecipitation method led to textural characteristics different from the other catalysts. XRD analysis showed the formation of crystalline CuO for contents equal to or greater than 3,3 wt% of copper. TPR analysis indicated that there was a strong interaction at the interface between the substrate and the copper species dispersed together with the lowering of the temperature reduction of CuO and the partial reduction of ceria at lower temperatures. The catalytic activity results showed a better performance of the (IS) catalysts, which showed higher conversions at lower temperatures. Concerning the aging process, there was a significant decrease in the efficiency of the catalysts. A comparison with catalysts doped with noble metal showed good performance of the catalysts doped with copper, with the advantage of these presenting N2O emission restricted to low temperatures
Casapu, Maria Cristina. "NOx storage-reduction catalysts : material aspects, thermal ageing and reactivation". kostenfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:30178.
Texto completoWang, Fagen. "Hydrogen production from steam reforming of ethanol over an Ir/ceria-based catalyst : catalyst ageing analysis and performance improvement upon ceria doping". Phd thesis, Université Claude Bernard - Lyon I, 2012. http://tel.archives-ouvertes.fr/tel-00967128.
Texto completoKniep, Benjamin-Louis. "Microstructural modifications of copper zinc oxide catalysts as a function of precipitate ageing". [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975886851.
Texto completoLassi, U. (Ulla). "Deactivation Correlations of Pd/Rh Three-way Catalysts Designed for Euro IV Emission Limits:effect of Ageing Atmosphere, Temperature and Time". Doctoral thesis, University of Oulu, 2003. http://urn.fi/urn:isbn:9514269543.
Texto completoVan, Zandycke Sylvie. "The role of catalase and glutathione on replicative lifespan in Saccharomyces cerevisiae". Thesis, Oxford Brookes University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325260.
Texto completoKhudur, Ivan. "Aluminium alloys ability to catalyse the oxidation of biodiesel : Development of a procedure to test alloys". Thesis, KTH, Kraft- och värmeteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215060.
Texto completoBiodiesel är ett förnybart och biologiskt nedbrytbart bränsle som har möjligheten att ersätta konventionell diesel och minska föroreningen av miljön. Trots dess fördelar så har det visats att bränslet skadar motorerna i fordon, vilket beror på dess oxidativa egenskaper. Olika metaller, såsom koppar, zink och aluminium förekommer i fordons bränslesystem, och dessa har påvisats katalysera oxidationen av biodiesel. Flera studier har genomförts där interaktionen mellan de tidigare nämnda metallerna och biodiesel har undersökts. En del av dessa studier har fått motsägelsefulla resultat när det kommer till interaktionen mellan aluminium legeringar ochbiodiesel. Detta projekt har därför haft som syfte att ta fram en enkelt metod att jämföra metallers katalystiska effekt på biodieslets oxidations stabilitet, samt använda denna metod för att bedöma nedbrytningen av biodiesel i kontakt med aluminium legeringar. Olika uppvärmningsmetoder och täckningsmaterial undersöktes med hjälp av biodiesel gjord på rapsolja, RME, för att ta fram mätmetoden. När ett tillvägagångssätt hade fastlagts, så sänktes bitar av tre olika bränslefilterhus tillverkade av aluminium legeringar, och tre olika aluminium tackor med olika kopparhalter i RME och bränslets stabilitet mättes. Användning av ugn vid 80 °C för att testa biodieslets oxidations stabilitet gav de mest upprepbara resultaten, och sprejfärgen Auto K billack spray Universal var mest kompatibel att använda som täckningsmaterial. Den inre, obehandlade ytan av bränslefilterhusen visade sig inte påverka oxidations stabiliteten på biodieslet. Aluminijm legeringar med en högre koppar halt bröt ned RME lite mer än aluminium legeringar med lite/ingen koppas, men endast om ytan hade blivit mekaniskt behandlad. Detta ger slutsatsen att aluminium legeringar kan minska biodieslets stabilitet om det innehåller mycket koppar och om legeringens yta har blivit behandlad. Däremot så kan den reduktionen av oxidations stabiliteten bero på andra faktorer och det rekommenderas därför att genomföra fler experiment med aluminum legeringar och biodiesel.
Blasetti, Cecilia. "Extensive oxidation treatments: ageing effects on a catalytic model system studied in UHV by STM". Doctoral thesis, Università degli studi di Trieste, 2009. http://hdl.handle.net/10077/3096.
Texto completoThis thesis concerns a surface science approach for the investigation of the ageing process of a model catalyst. It combines extreme oxidation conditions with Ultra High Vacuum (UHV) compatible characterization techniques. Our model system was the surface oxide formed on Rh(110); to grow such oxide, we used three alternative oxygen sources, optimizing for each case the preparation recipe. When dosing molecular oxygen, pressures in the ∼ 10− 4 mbar range were used, therefore bridging, to some extent, the pressure gap. For characterization of the oxides we used mainly Scanning Tunneling Microscopy (STM) and Thermal Desorption Spectroscopy (TDS), providing atomic scale and desorption mechanism information, respectively. Low Energy Electron Microscopy (LEEM) and X-ray Photoelectron Specroscopy (XPS) complemented our measurements with large scale morphology and reactivity data and with chemically resolved results. To mimic real catalytic conditions, we setup an ageing protocol consisting of cycles of oxidation and annealing in UHV (up to more than ∼ 40), with each of the three oxygen sources. In this way, we were able to observe two different kinds of ageing: a “contaminant-driven” and an “intrinsic” one, caused by the iterative oxidation procedure. The latter is connected to the presence of a new species we detected on the (1 × 1) surface obtained after the oxide desorption, that we named “units” (or ageing fingerprints). By decreasing their number we were able to show that the intrinsic ageing is, at least partially, reversible. We could not uniquely determine the structure of the “units”, but plausible models are proposed. ------------------------------------------------
Questa tesi si occupa dello studio dell’invecchiamento artificiale di un catalizzatore modello, combinando condizioni di ossidazione estreme con le tecniche di caratterizzazione, compatibili con l’ultra-alto-vuoto (UHV), proprie della scienza delle superfici. Il nostro sistema modello era l’ossido superficiale formato sul Rh(110); per crescere questo ossido, abbiamo utilizzato tre sorgenti alternative di ossigeno, ed abbiamo ottimizzato la ricetta di preparazione nei singoli casi. Utilizzando l’ossigeno molecolare abbiamo dosato a pressioni dell’ordine di ca. 10− 4 mbar, ed in questo modo abbiamo in parte colmato la “pressure gap” che solitamente divide gli studi su sistemi modello da quelli di catalisi reale. Per caratterizzare gli ossidi abbiamo usato principalmente la microscopia a scansione ad effetto tunnel STM e la spettroscopia di desorbimento termico TDS, che ci hanno fornito rispettivamente informazioni su scala atomica e sul meccanismo di desorbimento. Le tecniche LEEM e XPS hanno contribuito in modo complementare alle nostre misure con dati di morfologia e reattività su larga scala, da un lato, e con dati risolti chimicamente, dall’altro. Per simulare le condizioni della catalisi reale, abbiamo sviluppato un protocollo di invecchiamento (“ageing”) composto da cicli di ossidazione e riscaldamento in ultra-alto-vuoto (fino a ca. 40), con ognuna delle tre sorgenti di ossigeno. Seguendo questa procedura, abbiamo osservato due diversi tipi di invecchiamento dell’ossido di rodio: un primo tipo dominato dalla presenza di contaminanti, ed un secondo invece che abbiamo chiamato “intrinseco”, causato cioè dalle ripetute ossidazioni. Quest’ultimo dipende dalla presenza di una nuova specie osservata sulla superficie (1 × 1) che si ottiene a seguito del desorbimento di ciascun ossido, che abbiamo chiamato “units” (o -ageing fingerprint-). Ri- ducendo la densità di questa specie siamo stati in grado di mostrare come l’invecchiamento intrinseco sia, almeno in parte, reversibile. Non abbiamo potuto determinare univocamente la struttura delle “units”, ma alcuni modelli possibili vengono proposti.
XXI Ciclo
1981
Easterling, Vencon G. "The Effects of Ceria Addition on Aging and Sulfation of Lean NOx Traps for Stand Alone and LNT-SCR Applications". UKnowledge, 2013. http://uknowledge.uky.edu/cme_etds/17.
Texto completoMehsein, Kawsar. "Degradation mechanisms study of NOx after-treatment SCR system using urea on a Diesel Particulate Filter catalyst". Thesis, Montpellier, Ecole nationale supérieure de chimie, 2017. http://www.theses.fr/2017ENCM0012.
Texto completoThe selective catalytic reduction (SCR) by urea or ammonia is a well-known method to meet the European emission regulation requirements concerning the reduction of nitrogen oxides (NOx) emissions from Diesel engines. In order to optimize the NOx reduction activity at all temperature range, a copper-exchanged zeolite (Cu-Zeolite) SCR catalyst is combined to a Diesel Particulate Filter (SCRF). However, during the continuous regeneration of the particulate filter, the SCRF catalyst will go through numerous constraints such as variable high temperature, poisoning compounds from Diesel fuel and engine oil, during the entire vehicle life of the after-treatment line. Moreover, the European legislation requires a durability of the after-treatment line for about 160,000km. Understanding the degradation of the SCRF catalyst by the hydrothermal ageing is of interest to apprehend the deactivation mechanism in order to develop a stable material. In the present work, accelerated hydrothermal ageing in laboratory oven and also a real driving ageing of an SCRF catalyst, included in an after-treatment line for about 120,000km, were performed. The different results obtained help to apprehend the degradation mechanism of a Cu-Zeolite SCRF catalyst performance and also to find a correlation between a 120,000km real driving ageing and an equivalence oven aged SCRF catalysts. Moreover, rapid characterization methods, to detect the hydrothermal ageing status of an SCRF catalyst, have been selected. Finally, a mathematical model, based on experimental results, has allowed to describe the degradation of the ammonia storage capacity of the SCRF catalyst with the hydrothermal ageing
Jelena, Kiurski. "Mehanizmi starenja katalizatora za hidrodesulfurizaciju". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 1997. https://www.cris.uns.ac.rs/record.jsf?recordId=71439&source=NDLTD&language=en.
Texto completoAbstract was processed by technology for Optical character recognition (OCR).Deactivation studies of hydrodesulphurization catalysts were performed, based on both aging simulation in laboratory conditions and investigation of catalysts from an industrial HDS plant. Broad interval of conditions applied in laboratory simulation (temperature, treatment duration, oxidation and inert atmospheres) was the basis for evaluating the effect of different parameters on catalyst aging kinetics and defining critical conditions, with emphasis on regeneration procedure. The investigations of two catalyst types, NiO-MoO3/y-Al2O3 and C0O-MoO3/y-Al2O3, and NiO/Al2O3 binary model systems, using complementary methods for structural and textural investigations of porous solid systems, enabled the insight in aging mechanisms of these complex catalytic systems. The oxidation atmosphere, especially water vapor, is critical for the rate of structural and textural changes in the catalysts. Segregation in active phase, interaction with the support, sintering and loss of active component from the catalyst are the simultaneous processes bringing about the irreversible deactivation of the catalyst. The temperature gradient in working conditions and possible formation of hot spots in catalyst reactor bed, affected also by changes of diffusion characteristics of catalyst grain, are crucial factors for segregation of molybdenum oxide precursor, which effect is pronounced during regeneration. The mechanism of HDS catalyst aging is based on intermediary presence of moIybdenum oxide liquid phase on the support surface, facilitating intensive sintering and interactions of other phases of catalytic system.
Xia, Yuzhen. "Carbone fonctionnalisé pour une meilleure performance des piles à combustible". Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0116/document.
Texto completoIn the development of the performances of PEM fuel cell, sulfonated Pt/Vulcan catalysts were prepared by grafting with either polystyrene sulfonate (PSSA) or with 4-phenysulfonic acid (PSA). The influences of the graft ratio, the amount of Nafion and the gas diffusion layer, on the electrochemical performances were studied in a half-cell and membrane electrode assembage (MEA). Larger electrochemical surface area of the catalyst was obtained in the presence of microporous layer on the carbon paper, as well as higher ORR current and lower charge transfer resistance. PSSA was grafted onto Pt/Vulcan catalysts by in-situ radical polymerization with 5, 10 and 20 wt.% sodium styrene sulfonate. It was presented in the half-cell tests and fuel cell tests that the catalysts grafted with 5 and 10 wt.% sulfonated groups performed improved properties. Pt/Vulcan catalysts were also grafted with 5.8, 11.6 18.0 and 23.3 wt.% PSA. Compared with non-functionalized catalysts, significant developments were achieved because of the sulfonation. The MEA with 18.0 wt.% PSA was studied in accelerated durability tests and showed excellent durability after 3000 cycles. For half-cells and MEAs with catalysts grafted with 5wt.% PSSA or PSA groups, low Nafion addition resulted in to lower performances. However, the MEAs with 10 and 20 wt.% PSSA exhibited an enhanced performance than the counterparts with 0.50 mg•cm-2 Nafion
Havil, Patrick. "Influence du vieillissement thermique sur les proprietes physico-chimiques et la reactivite des catalyseurs mono et bimetalliques a base de platine et/ou rhodium sur alumine ou sur cerine". Paris 6, 1988. http://www.theses.fr/1988PA066291.
Texto completoSaïd, Hassane Charifat. "Valorisation chimique et biotechnologique de la biodiversité marine de l’Archipel des Comores : recherche de molécules naturelles anti-âge". Thesis, La Réunion, 2020. https://elgebar.univ-reunion.fr/login?url=http://thesesenligne.univ.run/20_16_C_SaidHassane_Diff.pdf.
Texto completoHuman aging creates a breeding grounds for the development of conditions that get more common as we get older. In order to slow or delay the onset of physiological or pathological effects of aging process, different research strategies can be developed. Thus, in the context of this PhD work, several marine sponges collected in Mayotte, were evaluated for their capacity to produce metabolites with anti-aging properties. The evaluation of biological activities was carried out on the following biological targets: elastase and tyrosinase (skin aging), CDK7 and proteasome (cancers), Fyn kinase (Alzheimer's disease), catalase (oxidative stress) and sirtuin 1 (different biological functions). Because of their biological activities, the marine sponges Lendenfeldia sp. and Scopalina hapalia were selected for chemical studies. The extraction, isolation and identification were undertaken by various chromatographic (MPLC, HPLC ...) and spectroscopic (HRMS, 1D and 2D NMR) techniques. Twenty metabolites belonging to the chemical classes of alkylglycerols, butenolides, diketopiperazines, epidioxysterols, phospholipids and polybromodiphenyl ethers were isolated from these sponges. It should be noted that four new metabolites of new structures were isolated from S. hapalia whose chemical composition has been little studied up until now. Furthermore, there is a paucity of information on its microbial community and its potential for bioactive metabolites production. The bacterial community associated with S. hapalia was therefore characterized by a targeted metagenomic approach. This study shed light on a diverse community highly dominated by Proteobacteria followed by Cyanobacteria, Bacteroidetes, Planctomycetes as well as Actinobacteria. The use of cultivation approach allowed the isolation of microorganisms affiliated to genera Bacillus, Micromonospora, Salinispora, Rhodococcus, Aspergillus, Chaetomium and Nigrospora. Finally, the potential of isolated microorganisms to produce bioactive molecules was investigated in two steps: 1) by implementing conventional culture techniques coupled with in situ recovery of the molecules produced by the microorganisms, 2) by screening the produced crude extracts from thirty isolates for anti-aging activities. The results highlighted fifteen promising microorganisms producing bioactive metabolites with various anti-aging activities
Anguita, Paola. "Impact des biocarburants sur le système d’oxydation catalytique des véhicules diesel". Thesis, Lyon, 2018. http://www.theses.fr/2018LYSE1181.
Texto completoThe more restrictive regulations to reduce pollutants emissions, especially CO2, promote the use of biofuels. However, biodiesel contains inorganic elements (Na, K, Ca and P) that reduce the durability of the after-treatment catalysts. This work aims to evaluate the performance of Diesel Oxidation Catalysts (DOCs, PtPd/CeZrO2/La-Al2O3 reference catalyst). The characterization results have shown that the above-mentioned impurities affect the physico-chemical, redox, surface and catalytic properties. Although the catalyst crystalline structure of reference catalyst did not change after impurities incorporation, the specific surface area decreased. The redox ability was also decreased when Na, K and Ca impurities are present due to their low electronegativity, which increased the oxygen interaction. This high interaction seems to be responsible of the enhanced C3H6 reaction rate. NO-TPD results evidenced that the high basicity of Na, K and Ca impurities resulted in an increase of NO adsorption strength. Accordingly, DRIFT results showed the presence of NO intermediates adsorption associated to the electrostatic field created by these cations, hindering NO oxidation. CO adsorption was also promoted, enhancing CO reaction rate. The formation of cerium phosphate was also observed, which could stabilize the Ce3+ oxidation state (checked by XPS), decreasing NO oxidation due to the blockage of catalytic sites. Nevertheless, CO and C3H6 co-oxidations were enhanced by avoiding self-poisoning. After catalyst hydrothermal aging, the effect of impurities was masked by the sintering of Pt/Pd active sites, which decreases the DOC catalytic performances
Foster, Adam Lamar. "Accelerated thermal aging of iron-zeolite SCR catalyst on an engine bench". 2008. http://etd.utk.edu/2008/December2008MastersTheses/FosterAdamLamar.pdf.
Texto completoOttinger, Nathan Andrew. "Effects of high temperature cyclic aging on a fully-formulated lean NO[subscript x] trap catalyst". 2008. http://etd.utk.edu/August2008MastersTheses/OttingerNathanAndrew.pdf.
Texto completoFurtado, Nélida Sofia Tavares. "Ageing on commercial automotive catalysts, a structure reactivity study". Master's thesis, 2014. http://hdl.handle.net/10362/13934.
Texto completoFoster, Adam Lamar. "Accelerated Thermal Aging of Fe-Zeolite SCR Catalysts on an Engine Bench". 2008. http://trace.tennessee.edu/utk_gradthes/375.
Texto completoCheng, Ching-Li y 鄭敬俐. "An immunohistochemical study of Mn-SOD and catalase changes during aging". Thesis, 1998. http://ndltd.ncl.edu.tw/handle/05381558969115114959.
Texto completoKauser, Sobia, Gillian E. Westgate, M. R. Green y Desmond J. Tobin. "Human Hair Follicle and Epidermal Melanocytes Exhibit Striking Differences in Their Aging Profile which Involves Catalase". 2011. http://hdl.handle.net/10454/7453.
Texto completoCanities or senile hair graying, a universally recognized sign of aging, remains unresolved in terms of physiological causes, although a strong genetic contribution is understood (Gunn et al., 2009). As the hair fiber continues to grow long after melanin production ceases, we suggest that melanocytes in the hair follicle may be more sensitive to the impact of chronological aging than are keratinocytes. Moreover, follicular melanocytes also age more markedly than those in the overlying epidermis. The hair follicle provides a unique opportunity to decouple the impact of age on two hair follicular tissue functions: hair formation and hair pigmentation. ... This study provides analysis of race, age, and anatomically matched cultures of adult human epidermal and hair follicle melanocytes (HFMs).
Kniep, Benjamin-Louis [Verfasser]. "Microstructural modifications of copper zinc oxide catalysts as a function of precipitate ageing / vorgelegt von Benjamin-Louis Kniep". 2005. http://d-nb.info/975886851/34.
Texto completoWood, John M., H. Decker, H. Hartmann, Bhavan Chavan, Hartmut Rokos, J. D. Spencer, Sybille Hasse et al. "Senile hair graying: H2O2-mediated oxidative stress affects human hair color by blunting methionine sulfoxide repair". 2009. http://hdl.handle.net/10454/6241.
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