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Krumnow, April Anne. "Preserving biological materials in protective polymers." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Dissertation/KRUMNOW_APRIL_38.pdf.
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Geoffroy, Laura. "Design of new fire protective multi-materials." Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1R014.
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Le feu peut causer de graves dégâts matériels et humains. Par conséquent, il est important de mettre au point de nouvelles protections contre le feu. Pour concevoir de nouveaux systèmes toujours plus efficaces, une approche scientifique innovante a été envisagée au sein de cette thèse. Elle consiste à combiner différents concepts et matériaux, tout en jouant sur leur design plutôt que leur formulation pour atteindre de meilleures propriétés de protection thermique. Ainsi, deux nouveaux multi-matériaux de protection contre le feu ont été élaborés, visant dans un cas à limiter la réaction au feu, et dans l’autre cas à augmenter la résistance au feu d’un substrat. Dans une première partie, la fabrication additive s’est révélée être un procédé de choix pour concevoir le matériau ayant une faible réaction au feu. Un design à structure sandwich original inspiré du vivant (nid d’abeille) a été conçu, imprimé en 3D, et optimisé par la combinaison de nombreux concepts (système inhibiteur d’oxygène, barrière physique, revêtement basse émissivité). Grâce à cette association de design et concepts, le multi-matériau, exposé à un flux de chaleur radiatif externe de 50 kW/m2 basé sur la norme ISO 13927 du cône calorimètre, a montré une très faible réaction au feu avec notamment une rapide extinction de flamme et un faible dégagement de chaleur total (inférieur à 10 kW/m2), témoignant de son excellente efficacité. Dans une seconde partie, un système faisant office de barrière thermique a été développé afin de protéger un substrat face à une exposition au feu de 116 kW/m2 (test « burn-through » représentatif du standard aéronautique ISO2685). Cette barrière, combinant les phénomènes d’intumescence et de délamination au sein d’un même design, a permis de réduire considérablement la propagation de la chaleur au sein du système. Le substrat a ainsi été protégé, avec une température en face arrière restant inférieure à 250°C après plus de 15 minutes d’exposition au feu. L’efficacité de ce système optimisé a ensuite été validée sur d’autres substrats. Cette étude prouve que la modification du design de divers matériaux constitue une voie prometteuse pour améliorer la performance des systèmes de protection contre le feuFire can cause severe material damage as well as human casualties. The development of new fire protective systems is thus of prime importance. In order to conceive new and more efficient systems, an innovative scientific approach has been considered within this PhD work. It consists in combining various concepts and materials while changing their design rather than their chemistry to achieve superior fire protection. In this way, two novel fireproofing multi-materials were developed and aimed on the one hand to limit the reaction to fire, and on the other hand to increase the fire resistance of a substrate. In the first part, additive manufacturing was selected as a process of choice for designing a material with a low reaction to fire. An original bio-inspired sandwich design (honeycomb-like structure) was elaborated, 3D printed and optimized by the combination of numerous concepts (oxygen inhibitor system, physical barrier, low emissivity coating). Thanks to this association of design and concepts, the multi-material exposed to an external radiant heat flux of 50 kW/m2 based on the ISO 13927 standard of the mass loss cone calorimeter has shown a very low reaction to fire with a fast flame extinguishment and an extremely low total rate of heat release rate (less than 10 kW/m2) evidencing its outstanding efficiency. In a second part, a system acting as a fire barrier was developed to protect a substrate against a fire exposure of 116 kW/m2 (burn-through fire testing mimicking the aeronautical standard ISO2685). Intumescence and delamination phenomena were combined within the same design to elaborate this barrier. This new and optimized assembly dramatically reduces heat propagation and protects the substrate, its backside temperature remaining below 250°C after more than 15 minutes of fire exposure. The effectiveness of this fire barrier was finally tested on other substrates to extend its use. This study proves that modifying the design of various materials can be a promising way to design new and very effective fire protective systems
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Ankrah, Stephanie. "Protective materials for sporting applications : football shin guards." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288869.
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Yener, Fatih Yalçın Güneş Korel Figen. "Development of antimicrobial protective food coating materials from edible alginate films/." [s.l.]: [s.n.], 2007. http://library.iyte.edu.tr/tezlerengelli/master/biyoteknoloji/T000658.pdf.
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Lange, Hanna. "Emulsion polymerization of vinyl acetate with renewable raw materials as protective colloids." Thesis, KTH, Skolan för kemivetenskap (CHE), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-41019.
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Emulsion polymerizations of vinyl acetate (VAc) were performed by fully or partially replacing poly(vinyl alcohol) (PVA) with renewable materials as protective colloids or by adding renewable materials, as additives or fillers, to the emulsions during or after polymerization. The purpose of the study was to increase the amount of renewable materials in the emulsion. A total of 19 emulsions were synthesized. Different recipes were used for the synthesis. The following renewable materials were studied; hydroxyethyl cellulose (HEC) with different molecular weights, starch and proteins. HEC and starch were used as protective colloids. Proteins were used as additives or fillers. Cross-linking agent A and Cross-linking agent B were used as cross-linking agents. A total of 26 formulations were pressed, either cold or hot. The synthesized emulsions were evaluated with respect to pH, solids content, viscosity, minimum film formation temperature (MFFT), glass transition temperature (Tg), particle size and molecular weight (Mw). The tensile shear strengths of the emulsions were evaluated according to EN 204 and WATT 91. It was possible to fully, or partially, replace PVA as protective colloid with renewable materials. It was also possible to use renewable materials as additives or fillers in the emulsions. The emulsions obtained properties that differed from the reference. Generally, emulsions with HEC as protective colloid showed lower viscosity and slightly higher MFFT, Tg and molecular weight than emulsions with PVA as protective colloid. Larger particle sizes than the reference were obtained for emulsions containing PVA combined with renewable materials. The emulsion with starch as protective colloid exhibited the largest particle size. 10 formulations passed the criteria for D2. The emulsions where PVA was fully or partially replaced with HEC or starch showed a water resistance similar to the reference (around D2). The addition of protein did not decrease the water and heat resistance compared to the reference. Addition of protein after polymerization increased the water resistance (D2) compared to addition during polymerization. Addition of cross-linking agents did not increase the water resistance further. Two formulations passed the criteria for D3. The emulsion in the first formulation had PVA as protective colloid and protein B was added during polymerization. The emulsion in the second formulation had HEC as protective colloid. To both of these emulsions, protein A was added after polymerization, as a filler, combined with Cross-linking agent B as cross-linking agent before hot pressing. The first formulation also showed a good heat resistance (passed the criteria for WATT 91).
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Berger, Brian Lee. "Development of a Protective Coating for TAGS-85 Thermoelectric Material." University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1375129912.
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Turel, Tacibaht Gowayed Yasser. "Gas transmission through microporous membranes." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/FALL/Polymer_and_Fiber_Engineering/Dissertation/Turel_Tacibaht_38.pdf.
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Shen, Fengyu. "Study of Perovskite Structure Cathode Materials and Protective Coatings on Interconnect for Solid Oxide Fuel Cells." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/74973.
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Solid oxide fuel cells (SOFCs) are promising devices to convert chemical energy to electrical energy due to their high efficiency, fuel flexibility, and low emissions. However, there are still some drawbacks hindering its wide application, such as high operative temperature, electrode degradation, chromium poisoning, oxidization of interconnect, and so on.
Cathode plays a major role in determining the electrochemical performance of a single cell. In this dissertation, three perovskite cathode materials, La0.6Sr0.4Co0.2Fe0.8O3 (LSCF), Ba0.5Sr0.5Co0.2Fe0.8O3 (BSCF), and Sm0.5Sr0.5Co0.2Fe0.8O3 (SSCF), are comparatively studied through half-cells in the temperature range of 600-800 ºC. Sm0.2Ce0.8O1.9 (SDC) block layer on the yttria-stabilized zirconia (YSZ) electrolyte can lead to smaller polarization resistances of the three cathode materials through stopping the reaction between the cathodes and the YSZ electrolyte. SDC is also used as a catalyst to increase the oxygen reduction reaction (ORR) rate in the LSCF cathode.
In addition, interconnect is protected by CoxFe1-x oxide and Co3O4/SDC/Co3O4 tri-layer coatings separately. These coatings are demonstrated to be effective in decreasing the area specific resistance (ASR) of the interconnect, inhibiting the Cr diffusion/evaporation, leading higher electrochemical performance of the SSCF-based half-cell. Only 1.54 at% of Cr is detected on the surface of the SSCF cathode with the Co0.8Fe0.2 oxide coated interconnect and no Cr is detected with the Co3O4/SDC/Co3O4 tri-layer coated interconnect.
Finally, single cells with LSCF, BSCF, and SSCF as the cathodes are operated in the temperature range of 600-800 °C fueled by natural gas. BSCF has the highest power density of 39 mW cm-2 at 600 °C, 88 mW cm-2 at 650 °C, and 168 mW cm-2 at 700 °C; LSCF has the highest power density of 263 mW cm-2 at 750 °C and 456 mW cm-2 at 800 °C. Activation energies calculated from the cathode ASR are 0.44 eV, 0.38 eV, and 0.52 eV for the LSCF, BSCF, and SSCF cathodes respectively, which means the BSCF cathode is preferred. The stability test shows that the BSCF-based single cell is more stable at lower operative temperature (600 °C) while the LSCF-based single cell is more stable at higher operative temperature (800 °C).Ph. D.
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Yan, Jin. "Aspects of instrumented indentation with applications to thermal barrier coatings." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 177 p, 2007. http://proquest.umi.com/pqdweb?did=1397913961&sid=17&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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DRENSKY, GEORGE KERILOV. "AMBIENT AND HIGH TEMPERATURE EROSION INVESTIGATION OF MATERIALS AND COATINGS USED IN TURBOMACHINERY." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1022846322.
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Sharer, Sahir Zalilah. "Investigation of protective mechanisms of organic coatings by thermal testing and electrochemical techniques." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:8fb242d3-4836-4082-ae95-b7990b593f8a.
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This work investigated the protection of mechanism of organic coatings on steel exposed to 3% sodium chloride solution at 50°C, coupled with the use of electrochemical impedance spectroscopy (EIS) to monitor progress of corrosion and degradation of coating. Unlike Walter, EIS measurement was conducted at 50°C as well as after cooling, and measurements at intermediate temperatures have been used to characterize the dependence of the process involved. The proposition that corrosion rate is controlled by the ionic resistance of an organic coating has been tested. EIS results were fitted to a model circuit and changes in the film resistance and charge-transfer resistance with temperature were analyzed to deduce activation energies for the processes involved. Surprisingly, the calculated activation energy for coating resistance is significantly lower than the activation energy for the charge transfer resistance. This suggests that ion conduction in the coating, as apparent in an AC measurement, cannot be controlling the corrosion rate. Potentiostatic pulse tests on coated metal enable iR-corrected polarization curves to be plotted at different temperatures. From this, the activation energy determined from the corrosion currents also higher matches the higher activation energy value calculated from the charge transfer resistance. However, measurements of coating resistance on free films of the same coating also generate higher activation energy values, leaving two possible models that can account for the results.
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Pelham, Todd B. "DEGRADATION OF PROTECTIVE GLOVE MATERIALS EXPOSED TO COMMERCIAL PRODUCTS: A COMPARATIVE STUDY OF TENSILE STRENGTH AND GRAVIMETRIC ANALYSES." CSUSB ScholarWorks, 2014. https://scholarworks.lib.csusb.edu/etd/107.
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ABSTRACT
Current glove guides attempt to assist in recommending which type of glove is appropriate for handling chemicals; however, they include information on less than 1% of the 89 million chemical products available today.
This study offers a solution by testing five durable polymer materials against 50 chemicals, using two rapid chemical degradation assessment techniques. The first technique involves gravimetric analysis of the weight change following constant immersion against the chemical mixture. The second method uses tensile strength to assess molecular changes in the polymer structure.
This study is focused on addressing three issues of concern. First, this study examines if current degradation testing methods are adequate to determine chemical resistance against complex mixtures. Secondly, this study will be used to determine if current degradation information on pure chemicals is effective in predicting degradation of complex chemical mixtures, based on the major ingredient(s). Lastly, this study will start a chemical resistance index for complex mixed chemicals.
The results of this study clearly show that glove recommendations of pure and mixed chemicals are frequently different. In more than 58.4% of the cases, the mixed chemical requires a different glove than that of its pure chemical components. Results also show that glove recommendations based solely on weight change and/or permeation results are missing important information on tensile test performance. There are several instances (15.2%) in which the initial glove recommendation would be changed to a lower recommendation rating if the results of a tensile test were included.
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Swartz, Natasja Alexandria. "Rational Design of Materials for the Protection of Outdoor Metalworks." PDXScholar, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2488.
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Protective coatings are commonly used to protect culturally significant works, such as outdoor sculptures and architectural elements. Given the valuable nature of such metalworks, there is a surprising lack of environmentally sustainable coatings available for their conservation. High performance clear coatings are not developed or thoroughly tested for compatibility and longevity on outdoor sculptures. This can make the implementation of both methods and materials, no matter how promising in a lab, a significant hurdle for the conservation science community. This dissertation work initially aims to replace high-VOC formulations such as acrylic lacquers and waxes currently used as protective coatings for bronze with a waterborne coating by investigating the film formation differences between coating types. Such differences likely have implications for initial film barrier properties as well as long-term performance.
For coating any large-scale metal object, cost-effectiveness limits applicable coatings to commercially available resins with some minor adjustments. Additional requirements for protective coatings for artwork require they must also be transparent, reversible, easily applied and environmentally sustainable. The chemical and physical properties of polymeric coatings with nanoclays modifiers were investigated as they may offer superior weatherability and act as better barriers to water absorption than commonly used lacquers and waxes. This work ultimately finds that nanocomposites with poly(vinylidene fluoride) latex and chemically stabilized nanoclays significantly improved performance and may be a viable option in the protection of material cultural heritage. Protection of high value objects where aesthetics is also important, such as airplanes, buildings, and sculptures are among the possible applications for this research.
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Alkordy, Faris M. "Evaluation of Organic Protective Coatings as Corrosion Prevention for The Interior of Subsea Pipelines in Sour Gas Service." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2304.
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The purpose of this study was to examine the performance of several generic types of organic protective coatings as a corrosion protection method for the interior of subsea pipelines in sour gas media. The sour gas environment was simulated in the laboratory by the use of an Autoclave and the performance of the organic coatings was studied via the use of Electrochemical Impedance Spectroscopy (EIS) and Linear Polarization Resistance (LPR) tests to determine the coatings resistance, capacitance and corrosion behavior before and after the exposure to sour gas environment. The coating degradation and the corrosion products formed were examined by the use of SEM/EDS. The results indicated that both FBE and Novolac Epoxy coatings had excellent adhesion properties and chemical resistance. The Amine-Cured Novolac Epoxy coating exhibited good adhesion properties and chemical resistance. However, the Phenolic Epoxy coating started to degrade over time and corrosion took place under the coating.
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Mahmoudkhani, Amir H. "Structure-property relationships of organic and inorganic phosphites and phosphonates : design of new solid materials & thin protective layers /." Göteborg : Göteborg university, 2001. http://catalogue.bnf.fr/ark:/12148/cb40115101p.
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Batterham, Ian, and n/a. "Office Copying 1950-1970 : thermographic processes, their deterioration and preservation." University of Canberra. School of Resource, Environmental & Heritage Sciences, 2000. http://erl.canberra.edu.au./public/adt-AUC20060607.171830.
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This work looks at a range of copying processes used between 1950 and 1970 and which
can be gathered under the heading 'Thermography'. Thermography is a broad term
covering those processes which utilise heat to produce their image.
The main aims of the work were: to examine how and when each process was used; to
determine the chemistry of each process; to examine the permanence of existing copies
produced using the various processes; and to look at possible ways of improving the
preservation prospects of these copies.
These aims were addressed through both primary and secondary research mechanisms.
Research included examination of documentary source material, seeking out persons with
first hand knowledge of the development of the processes, as well as analysis of extant
copies from the various processes. Finally a series of preliminary experiments into the
aging properties of the papers and the possibilities of preservation through the use of
protective materials were carried out.
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Scholvin, Dirk. "Wear resistant nanostructured diamondlike carbon coatings on Ti-alloy." Thesis, Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180353/unrestricted/scholvin%5fdirk%5f200312%5fms.pdf.
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EverhartC, Charles. "The Electrodeposition of Fe-Ni-Cr Alloys from Aqueous Electrolytes." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1252092401.
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Thesis(M.S.)--Case Western Reserve University, 2009Title from PDF (viewed on 2010-01-28) Department of Chemical Engineering Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
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Aygun, Aysegul. "Novel thermal barrier coatings (TBCs) that are resistant to high temperature attack by CaO-MgO-Al₂O₃-SiO₂ (CMAS) glassy deposits." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1221589661.
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Fernandes, Fábio António Oliveira. "Biomechanical analysis of helmeted head impacts: novel materials and geometries." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/21227.
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Doutoramento em Engenharia MecânicaA cortiça é um material celular natural capaz de suster quantidades consideráveis de energia. Estas características tornam este material ideal para determinadas aplicações como a proteção de impactos. Considerando equipamentos de segurança passiva pessoal, os materiais sintéticos são hoje em dia os mais utilizados, em particular o poliestireno expandido. Este também é capaz de absorver razoáveis quantidades de energia via deformação permanentemente. Por outro lado, a cortiça além de ser um material natural, é capaz de recuperar grande parte da sua forma após deformada, uma característica desejada em aplicações com multi-impacto. Neste trabalho é efetuada uma avaliação da aplicabilidade da cortiça em equipamentos de segurança pessoal, especificamente capacetes. Vários tipos de cortiça aglomerada foram caracterizados experimentalmente. Impactos foram simulados numericamente para avaliar a validade dos modelos constitutivos e as propriedades utilizadas para simular o comportamento da cortiça. Capacetes foram selecionados como caso de estudo, dado as energias de impacto e repetibilidade de impactos a que estes podem ser sujeitos. Para avaliar os capacetes de um ponto de vista biomecânico, um modelo de cabeça humana em elementos finitos foi desenvolvido. Este foi validado de acordo com testes em cadáveres existentes na literatura. Dois modelos de capacete foram modelados. Um modelo de um capacete rodoviário feito de materiais sintéticos, o qual se encontra disponível no mercado e aprovado pelas principais normas de segurança de capacetes, que serve de referência. Este foi validado de acordo com os impactos da norma. Após validado, este foi avaliado com o modelo de cabeça humana em elementos finitos e uma análise ao risco de existência de lesões foi efetuado. Com este mesmo capacete, foi concluído que para incorporar cortiça aglomerada, a espessura teria de ser reduzida. Então um novo modelo de capacete foi desenvolvido, sendo este uma espécie de modelo genérico com espessuras constantes. Um estudo paramétrico foi realizado, variando a espessura do capacete e submetendo o mesmo a duplos impactos. Os resultados destes impactos e da análise com o modelo de cabeça indicaram uma espessura ótima de 40 mm de cortiça aglomerada, com a qual o capacete tem uma melhor resposta a vários impactos do que se feito de poliestireno expandido.
Cork is a natural cellular material capable of withstanding considerable amounts of energy. These features make it an ideal material for some applications, such as impact protection. Regarding personal safety gear, synthetic materials, particularly expanded polystyrene, are typically used. These are also able to absorb reasonable amounts of energy by deforming permanently. On the other hand, in addition to cork being a natural material, it recovers almost entirely after deformation, which is a desired characteristic in multi-impact applications. In this work, the applicability of agglomerated cork in personal safety gear, specifically helmets, is analysed. Different types of agglomerated cork were experimentally characterized. These experiments were simulated in order to assess the validity of the constitutive models used to replicate cork's mechanical behaviour. In order to assess the helmets from a biomechanical point of view, a finite element human head model was developed. This head model was validated by simulating the experiments performed on cadavers available in the literature. Two helmet models were developed. One of a motorcycle helmet made of synthetic materials, which is available on the market and certified by the main motorcycle helmets safety standards, being used as reference. This helmet model was validated against the impacts performed by the European standard. After validated, this helmet model was analysed with the human head model, by assessing its head injury risk. With this helmet, it was concluded that a thinner helmet made of agglomerated cork might perform better. Thus, a new helmet model with a generic geometry and a constant thickness was developed. Several versions of it were created by varying the thickness and subjecting them to double impacts. The results from these impacts and the analyses carried out with the finite element head model indicated an optimal thickness of 40 mm, with which the agglomerated cork helmet performed better than the one made of expanded polystyrene.
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Padki, Santosh Shankar. "Influence of surface tension and concentration of a non-ionic surfactant on the barrier effectiveness of a microporous polypropylene fabric for pesticide protective clothing." Thesis, This resource online, 1997. http://scholar.lib.vt.edu/theses/available/etd-08222008-063707/.
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Raynor, Jenny E. "Surface modification of titanium substrates with polymer brushes to control cell adhesion for bioapplications." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26653.
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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009.Committee Chair: Collard, David M.; Committee Co-Chair: Garcia, Andres J.; Committee Member: France, Stefan; Committee Member: Ragauskas, Arthur; Committee Member: Temenoff, Johnna. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Chrisanti, Santi. "The application of ion-exchanged clay as corrosion inhibiting pigments in organic coatings." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1198740679.
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Behrani, Vikas. "Surface Modifications of Steels to Improve Corrosion Resistance in Sulfidizing-Oxidizing Environments." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19708.
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Industrial and power generation processes employ units like boilers and gasifiers to burn sulfur containing fuels to produce steam and syn gas (H2 and CO), which can generate electricity using turbines and fuel cells. These units often operate under environments containing gases such as H2S, SO2, O2 etc, which can attack the metallic structure and impose serious problems of corrosion. Corrosion control in high temperature sulfur bearing environments is a challenging problem requiring information on local gaseous species at the surface of alloy and mechanisms of degradation in these environments. Coatings have proved to be a better alternative for improving corrosion resistance without compromising the bulk mechanical properties. Changes in process conditions may result in thermal and/or environment cycling between oxidizing and sulfidizing environments at the alloy surface, which can damage the protective scale formed on the alloy surface, leading to increase in corrosion rates. Objective of this study was to understand the effect of fluctuating environments on corrosion kinetics of carbon steels and develop diffusion based coatings to mitigate the high temperatures corrosion under these conditions. More specifically, the focus was : (1) to characterize the local gaseous environments at the surface of alloys in boilers; (2) optimizing diffusion coatings parameters for carbon steel; (3)understand the underlying failure mechanisms in cyclic environments; (4) to improve aluminide coating behavior by co-deposition of reactive elements such as Yttrium and Hafnium; (5) to formulate a plausible mechanism of coating growth and effects of alloying elements on corrosion; and (6) to understand the spallation behavior of scale by measuring stresses in the scales. The understanding of coating mechanism and effects of fluctuating gaseous environments provides information for designing materials with more reliable performance. The study also investigates the mechanism behind the effect of REs on scale adhesion and sulfidation behavior. Thus, the present work will have a broad impact on the field of materials and coatings selection for high temperature industrial environments such as boilers and gasifiers, and provides information on RE-modified aluminized coatings on carbon steel as an alternative for the use of bulk superalloys under high temperature sulfur bearing environments.
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Jain, Syadwad. "Corrosion and protection of heterogeneous cast Al-Si (356) and Al-Si-Cu-Fe (380) alloys by chromate and cerium inhibitors." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1145140821.
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Saillard, Audric. "Modeling and simulation of stress-induced non-uniform oxide scale growth during high-temperature oxidation of metallic alloys." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33898.
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The metallic alloys employed in oxidizing environment at high temperature rely on the development of a protective oxide scale to sustain the long-term aggressive exposition. However, the oxide scale growth is most of the time coupled with stress and morphological developments limiting its lifetime and then jeopardizing the metallic component reliability. In this study, a mechanism of local stress effect on the oxidation kinetics at the metal/oxide interface is investigated. The objective is to improve the understanding on the possible interactions between stress generation and non-uniform oxide scale growth, which might result in a precipitated mechanical failure of the system. Two different oxides are studied, alumina and chromia, in two different industrial systems, thermal barrier coatings and solid oxide fuel cell interconnects. A specific thermodynamic treatment of local oxide phase growth coupled with stress generation is developed. The formulation is completed with a phenomenological macroscopic framework and a numerical simulation tool is developed allowing for realistic analyses. Two practical situations are simulated and analyzed, concerning an SOFC interconnect and a thermal barrier coating system, for which oxide scale growth and associated stress and morphological developments are critical. The consequence of the non-uniform oxide growth on the system resistance to mechanical failure is investigated. Finally, the influences of material-related properties are studied, providing optimization directions for the design of metallic alloys which would improve the mechanical lifetime of the considered systems.
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Branco, José Soares Castelo. "Influência do pré-tratamento de superfícies de ligas de ferro na ancoragem de coberturas poliméricas para proteção contra a corrosão." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/75/75134/tde-01022017-152006/.
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O aço carbono vem sendo largamente utilizado na indústria de construção em geral, devido a sua resistência mecânica e baixo custo. Entretanto, devido a sua fraca resistência à corrosão são necessários estudos de diferentes métodos de proteção contra a corrosão. Sendo assim, no presente trabalho, o método de proteção contra a corrosão abordado foi o de aplicação de filmes poliméricos condutores mediante a utilização de pré-tratamentos de conversão com ácido fítico (HP), banho de sal de cério/peróxido de hidrogênio (Ce) e a combinação HP-Ce, para aumentar a resistência à corrosão e a aderência de filmes poliméricos. Essa aderência devido à importância frente os processos de corrosão foi quantificada com técnicas específicas de estudo de corrosão, nomeadamente, potencial de circuito aberto (PCA) e polarização potenciodinâmica (PP) em meio NaCl 0,6 mol/L aerado. Os revestimentos poliméricos usados foram a polianilina (PAni), poli-o-metoxianilina (POMA) e blenda de PAni-POMA sintetizados em meio de HP e de H2SO4. A caracterização feita por UV-Vis e FTIR mostrou que foi possível sintetizar os referidos polímeros, e SEM revelou morfologia compacta e granular. O comportamento eletroquímico das amostras foi investigado por OCP e PP em NaCl 0,6 mol/L antes e após 2 h de exposição no ambiente salino. Quando os revestimentos foram aplicados em substratos de aço carbono AISI 1020 sem pré-tratamentos, antes de exposição em solução salina, os resultados mostraram boa resistência e eficiência na proteção à corrosão devido a menor perda de adesão e maior efeito barreira. Após 2 h de exposição em solução salina, os resultados mostraram que a resistência e a eficiência na proteção à corrosão diminuiu de uma forma mais acentuada para PAni, POMA e menos para blenda de PAni-POMA sintetizados em meio de HP e de H2SO4, devido à perda de aderência provocada pela infiltração do eletrólito corrosivo através de poros dos filmes poliméricos. Com o intuito de aumentar a aderência dos revestimentos, pré-tratamentos do aço carbono AISI 1020 foram feitos com HP, Ce e HP-Ce e, constatou-se que a perda de aderência dos revestimentos de PAni, POMA e blenda de PAni-POMA aplicados sobre as amostras pré-tratadas com Ce e HP-Ce foi menor, e com HP foi maior comparada com a amostra sem pré-tratamento. Além disso, os revestimentos de blenda de PAni-POMA, apresentaram em todas amostras sem e com pré-tratamentos melhor desempenho em relação a PAni e POMA.Carbon steel has been widely used in the construction industry in general, due to its mechanical and low cost resistance. However, due to their low corrosion resistance are required studies of different methods of protection against corrosion. Therefore, in this study, the method of carbon steel AISI 1020 protection against corrosion was dealt with the application of polymeric film conductors using pre-treatments conversion with phytic acid (HP), cerium salt/hydrogen peroxide (Ce) bath and a combined HP-Ce, to increase the corrosion resistance and the adhesion of polymeric films. This adhesion is due to the importance forward corrosion processes, was quantified with specific corrosion study techniques in particular, open circuit potential (OCP) and potentiodynamic polarization (PP) in medium NaCl 0.6 mol/L aerated. Polymeric coatings used were the polyaniline (PAni), poly-o-anisidine (POMA), and blends of polyaniline-poly-o-anisidine (Pani-POMA) synthesized in phytic (HP) and sulfuric (H2SO4) acid means. The characterizations made by UV-Vis and FTIR showed that it was possible to synthesize said polymers, and SEM revealed compact and granular morphology. The electrochemical behaviors of the samples were investigated using OCP and PP in 0.6 mol/L NaCl solutions, before and after 2 h of exposure in saline environment. When polymers coatings were applied to carbon steel AISI 1020 without pretreatments, before of exposure in saline environment, results showed good resistance and high efficient corrosion protection due to less loss of adhesion coatings consequently, high barrier effect. After 2 hours of exposure in saline environment, the results showed that the resistance and efficient corrosion protection decreased largely for PAni, POMA and less for blends of PAni-POMA, due to loss of adhesion caused by the infiltration of corrosive electrolyte pores through the polymer matrix. In order to increase the adhesion of Pani, POMA and blends of Pani-POMA coatings, carbon steel pretreatments were made with HP, Ce and a combined HP-Ce, and found that the loss of adhesion of coatings applied to the pretreated samples with Ce and HP-Ce was lower, and with HP was higher compared to the sample without pretreatment. Moreover, blend of Pani-POMA coating showed in all samples, treated and untreated better performance than PAni and POMA.
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Ward, Ross Ritchie. "Keratin adsorbent material for chemical protective clothing." Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/19516/.
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Wool is potentially a valuable adsorbent that has been used for the depletion of airborne gas molecules. The aim of the research is to modify the complex hierarchical structure of wool fibres to form a reticulated internal porous structure within the fibre in order to ultimately enhance the adsorption capacity of wool and/or its composite fibres. In this study, the effects of several chemical treatments and their combinations on the formation of porous microstructure within wool fibres are studied. The techniques studied include oxidation (Formic acid treatment), oxidation/swelling (Ozone treatment in urea hydrogen peroxide solution) and education treatments (Sodium hydroxide treatments) and their combinations. Mesopore and macropore formations were evident after wool fibres and fabrics were treated with individual and consecutive chemical treatments. However, the pore formations after these chemical treatments did not produce materials with specific surface areas comparable to activated carbon. Despite this shortcoming there was evidence of both accessible and inaccessible pore formations within wool fibres. Additional physical selective degradation of raw and chemically modified wool fibres by using both electron beam irradiation using SEM and low pressure oxygen plasma irradiation treatments were identified to expand accessible pores or expose inaccessible pores formed within wool fibres after chemical treatment. Porous wool fibres with reticulated pore structures were evident after exposing the chemical pretreated wool fibres to low pressure plasmas. To enhance the adsorption capacity of the porous wool fibres formed, novel wool aerogel composite wool fibres have been developed. The resultant composite fibres were capable of adsorbing cyclohexane with up to 2.5 w/w% uptake. Also, similar uptakes were evident after testing without any sample pre-heating process. This demonstrates that wool-aerogel composite fabrics are capable of adsorbing VOCs at conditions similar to environments present during the use of CPC.
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Lawson, Thomas Ryan. "Micro-Raman spectroscopy and dry turning evaluations of nanostructured diamond films deposited on tungsten-carbide lathe inserts." Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2008m/lawson.pdf.
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Hardcastle, Rohan J. "Legal protection of human biological materials." Thesis, University of Oxford, 2005. https://ora.ox.ac.uk/objects/uuid:5ab37a9c-0780-46a7-a228-685020a429af.
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Do you own your body? Advances in science and the development of genetic databases have given this question an aura of modern controversy. However, English law governing separated biological materials is in an unsatisfactory state. Despite the enactment of the Human Tissue Act 2004 UK, it is not clear, for example, what property rights or non-proprietary interests living persons can claim over their separated biological materials. The development of clear legal principles is necessary, however, to enable individuals to have effective control over such materials and to enable the efficient use of such materials in medical research. Part I lays the theoretical foundation for the thesis. This opening part examines the nature of property and defines the theoretical position that the thesis adopts concerning property rights. Part I also sets out how English law protects property rights and the right to bodily integrity. Part II traces the evolution of the law in England, Australia and the US in relation to the human body as well as parts removed from dead bodies and living persons. This includes an examination of the Human Tissue Act 2004. Analysis demonstrates that, although property rights and non-proprietary interests are recognized in certain limited circumstances, it is an open question in English law as to whether or not a living person can claim property rights to separated biological materials. Part III of this thesis therefore develops and presents a principled basis in English law for the creation and legal recognition of property rights and non-proprietary interests in separated biological materials.
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Rodriguez, Alvaro A. "Corrosion inhibition mechanism of a surfactant admixture on carbon steel alloy ASTM A36 [UNS K02600] coated with a high performance UV-cured coating." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460564870.
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Yoon, Yuhchae. "Formation and breakdown on chromate conversion coatings on Al-Zn-Mg-Cu 7x75 alloys." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1101754567.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xxi, 282 p.; also includes graphics (some col.). Includes bibliographical references (p. 262-282).
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Lagodimos, Athanasios G. "Protective inventories in manufacturing systems." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335161.
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Donatus, Uyime. "Corrosion protection and microstructure of dissimilar materials." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/corrosion-protection-and-microstructure-of-dissimilar-materials(b419af19-3459-4218-9aff-b1b857a36cb4).html.
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Corrosion Protection and Microstructure of Dissimilar Materials. A thesis submitted to The University of Manchester for the degree of Doctor of Philosophy by Uyime, Donatus on the 30th of July, 2015.Investigations on the micro- and macro-galvanic corrosion mechanisms in un-coupled AA2024-T3 alloys, AA2024-T3 coupled with mild steel (with and without the influence of cadmium and under varying solution temperatures), dissimilar friction stir welds of AA5083-O and AA6082-T6 alloys and a friction stir welded AA7018 alloy have been carried out. Selected methods of preventing and / or minimising the investigated corrosion phenomena were also investigated. The investigation of the corrosion behaviour of the uncoupled AA2024-T3 alloy revealed that there are two distinct stages of polarization during the galvanostatic polarization of AA2024T3 alloy in de-aerated 3.5% NaCl solution. From the first stage, the relationships between the pitting incubation time, pitting potential and applied current density for AA2024T3 alloy in the de-aerated condition were established. Whilst studying the in situ corrosion phenomena on the uncoupled AA2024-T3 alloy using the scanning vibrating electrode technique (SVET),three distinct stages in the variation of the recorded current density values with time were revealed. Attempts were made to correlate these stages with the corrosion behaviour of the alloy. The study of the galvanic interactions between AA2024-T3 and mild steel revealed that AA2024-T3 is anodic to mild steel at room temperature, but polarity reversal of the couple starts (from a temperature as low as 35 oC upwards) when the couple is introduced into the solution above ambient temperature. Importantly, AA2024-T3 is clearly cathodic to mild steel at 60 oC, although with very low measured galvanic current values. Cadmium coating (at ambient temperature) on the mild steel reduced the galvanic corrosion of the couple by as much as 20 µA/cm2 because of the formation of a CdO/Cd(OH)2 layer on mild steel. In the study of the dissimilar friction stir welds of AA5083-O and AA6082-T6 alloys, it was observed that material flows (pushes but does not mix) more from the advancing side into the retreating side and that the mixture of materials is far from complete. Two welding speeds were compared; the welding speeds have no clear influence on the microhardness, but affected the mixing proportions in the flow arm and in the nugget stem. The faster welding speed resulted in increased susceptibility to corrosion because of the reduced tool rotation per weld length for heat generation and the mixing of materials. The heat affected zones of both alloys and the transition regions between the AA5083-O alloy and the AA6082-T6 alloy rich zones have been identified to be the regions that are most susceptible to corrosion. Anodizing the weld in order to minimise corrosion showed that the AA5083-O alloy rich zones materials, in the weld, oxidizes more during anodizing compared with the AA6082-T6 alloy rich zones. Sputtering deposition prior to anodizing, promotes the formation of a uniform oxide film across the entire weld zones and prevents the boundary dissolution that occurs when the dissimilar weld of AA5083-O and AA6082-T6 alloys is anodized in 4 M H2SO4 solution at 15 V at ambient temperature. The investigation of the corrosion susceptible regions in friction stir welded AA7018 alloy, which was based on the use of ISO 11846 immersion test and the potentiodynamic polarization technique in naturally aerated 3.5 % NaCl solution, revealed intergranular, crystallographic and second phase particle influenced mode of attack. The heat affected zone was found to be the most susceptible to corrosion.
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Freese, Samuel Henrique. "Estudo da capacidade de proteção anti-corrosiva de óleos de processo em materiais trefilados." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/75758.
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Aços carbono trefilados possuem como características excelentes propriedades mecânicas, estabilidade dimensional e bom acabamento superficial. Porém, para fornecimento deste material, um dos cuidados necessários é a proteção temporária contra a corrosão atmosférica, que pode ser definida como um processo resultante de reações químicas e/ou eletroquímicas, pelas quais metais e ligas se deterioram quando submetidos à ação climática. Para evitar / retardar este processo, usualmente é utilizada a aplicação de uma película de óleos formadores de barreira, protegendo o material base. Buscando avaliar a capacidade protetiva de óleos utilizados em materiais trefilados, foram selecionados 3 tipos de produtos usados no polimento e 3 tipos aplicados como proteção final. Diferentes combinações dos produtos foram avaliadas em amostras numa câmara úmida, mostrando que a capacidade protetiva dos óleos de proteção final está diretamente relacionada à sua densidade, diferentemente dos óleos de polimento que não apresentam uma relação direta com as propriedades avaliadas. Com base nestes resultados, pode-se prever a capacidade protetiva de óleos de proteção final utilizando sua densidade como referência, devido a esta relação ser linear, tendo outros fatores, como o tipo de óleo de polimento, afetando a constante da equação da curva.Drawn carbon steel has excellent mechanical proprieties, dimensional stability and good surface quality as characteristics. But, to supply this material, a necessary care is the temporary protection against atmospheric corrosion, which can be defined as a process resulting from chemical and / or electrochemical reactions, in which metals and alloys deteriorate when subjected to climate action. To avoid / retard this process, usually it’s used an application of an oil coat that protects the base material. Trying to understand the protective capacity of oils used in drawn materials, 3 products used in polishing process and 3 applied as final protection were selected. Samples tested in humid chamber with different combinations of products were evaluated, showing that the protective capacity of oils used as final protection is directly related with their density, a relation that is not presented in polishing oils. With these results we can forecast the protective capacity of oils used as final protection employing its density as reference, because of the linear relation, having another factors, like the type of polishing oil, affecting the curve equation constant.
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Chikatamarla, Ravikiran. "Optimisation of cushion materials for rockfall protection galleries /." Zürich : ETH, 2005. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16315.
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Bohlén, Martin, and Kristina Laurila. "Biopolymers as protection during transport of construction materials." Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18670.
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Construction materials are exposed to different conditions along the way from the sawmill, during storage and handling, until the materials are a part of the completed construction. During this time the materials may be exposed to moisture and dirt that can cause an attack by moulds. This, in turn, can give rise to health problems for individuals staying in the building and can also be the cause of a bad smell in the building. It is therefore necessary to protect the materials during this limited period of transport, storage, and handling.In this study two construction materials were used; untreated wood and plasterboard. As a possible protection for the materials coatings based on biopolymers were made. Biopolymers are totally degradable and are relatively cheap raw materials. The biopolymers used in this study were starch from potato, protein from corn, and acetylated mono- and diglyceride. Also, fungicides that function as inhibitors for mould growth were added to the coatings.Samples of wood and plasterboard were covered with the coatings using a paint sprayer. The samples were then exposed to a spore suspension containing spores from four of the most common mould species found attacking building material. The samples were then placed in three different climates differing in temperature and humidity. The conditions were in all three cases favourable for mould growth. The samples were placed in these conditions for a month and analysis of the growth on the samples was made once a week and according to a scale with five grades.The results varied very much between the samples, even between samples treated with the same coating, but an obvious trend gave indications of that it is possible to use biopolymers as protection for construction materials. In this study the coating based on the acetylated monoglyceride showed the best properties.Uppsatsnivå: C
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Coelho, Rodrigo Marquês. "Development of passive protection systems using cellular materials." Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/4518.
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Espartero, Jennifer C. "Polymeric Materials for Corrosion Protection in Geothermal Systems." Case Western Reserve University School of Graduate Studies / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=case1427901218.
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Dupin, Isabelle Valérie Simone. "Production and localisation of haze protective material from Saccharomyces cerevisiae /." Title page, table of contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phd934.pdf.
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MacLeod, William Robertson. "Novel photocleavable surfactants and other photolabile materials." Thesis, University of Strathclyde, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275149.
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Crawford, James Bruce. "Atmospheric microclimates : damaging & protecting indoor cultural heritage materials." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/87502/.
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This thesis in applied physics analyzes and solves problems regarding destructive and protective atmospheric microclimates in order to slow down the deterioration of indoor cultural heritage materials. Fresh approaches to two longstanding areas of concern are made in laboratory studies with a view to future field testing and evaluation by heritage conservation practitioners and museum display case manufacturers. Methods used for observing and analysing materials are macrophotography, optical microscopy, metallography, image analysis, X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. Structural engineering methods comprise geometric surveys and compression and deflection tests. Airtightness measurement techniques were tracer gas decay and pressure decay. Investigations into the corrosion of lead by oak-emitted volatile organic compounds (VOCs) revealed the presence of a rarely reported crystalline phase which was confirmed to be associated with modern oak. The morphology and composition of the observed products of corrosion were almost identical to those found in field environments, but differed in specific ways to prior laboratory studies which used synthetic or oak-emitted VOCs. Five novel surface protection treatments using materials derived from ethanolic solutions of high molecular weight carboxylic acids (CH3(CH2)n-2COOH; n = 10, 12, 14, 16 or 18) were tested atmospherically for five years. Hexadecanoic (n = 16) and octadecanoic acid (n = 18) treatments inhibited corrosion of lead exposed to oak VOCs by up to ≈60%. These effective treatment materials showed lamellar morphologies similar to those made from aqueous solutions of lower molecular weight carboxylic acids (n = 10 or 11). In contrast, two materials with non-lamellar morphologies made from ethanolic decanoic acid (n = 10) and tetradecanoic acid (n = 14) were found to increase corrosion. Inspections of industry-made medium-sized (≈1 m3 ) museum display cases with doors located systematic leaks in sorbent compartments, around exhibit compartment doors and in ceilings: providing vertical leakage circuits driven by stack pressures (˜0.1 Pa). A walk-in test chamber with a custom-designed tracer gas and environmental monitoring system was made to evaluate three devices for passively controlling airtightness on a pair of display cases. Airtightness of the cases was increased by 7 to 13 times. Despite remaining leaks in the ceilings, the cases reached or went beyond the microbarometric limit; due to new pressure-proofed sorbent compartments and novel convex gaskets for the compliant unframed exhibit compartment doors; solving leakage caused by restorative forces imposed by gaskets. The greatest airtightness (0.013±0.004 air exchanges daily) was achieved by a case retrofitted with a pair of high compliance bellows (Δ±2 Pa) with high conductance pipework, while being subjected to temperature cycling (Δ+2°C daily) and natural barometric pressure fluctuations. A formula derived from Ohm’s Law to evaluate the minimum required airway resistance of gaps in display cases was proposed as a new way to calculate, and then measure, the capability of a case to have its airtightness increased by installing bellows.
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Nalin, Laura. "Degradation of environmental protection coatings for gas turbine materials." Thesis, Cranfield University, 2008. http://dspace.lib.cranfield.ac.uk/handle/1826/4522.
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Nowadays, problems of component materials reliability in gas and oil-fired gas turbines focus on assessing the potential behaviour of commonly employed coatings, in order to avoid expensive and unpredictable failure in service and producing new materials whose performance meets life time and manufacturing/ repairing requirements. This MPhil project has investigated the oxidative and corrosive degradation mechanisms for some of the alloy/coatings systems (CMSX-4, CMSX-4/ RT22, CMSX-4/ CN91 and CMSX-4/ “LCO22”), which are currently used for turbines blades and vanes, in order to achieve a better knowledge of materials behaviour and to improve models for the prediction of turbine components’ lives. To achieve this target the study has made use of realistic simulations of turbine exposure conditions in combined with pre- and post-exposure metrology of bar shape materials samples, while optical microscopy has been applied to describe the microstructural evolution during the exposure and the products of the degradation for the hot corrosion. For high temperature oxidation, over extended periods of time (up to 10,000 hours), the research has allowed to describe the morphological changes in respect of the exposure time and temperature and to determine the oxidation kinetics experienced by the alloy and coatings. A model has been presented for predicting θ- α-Al2O3 growth. Moreover, using NASA COSP spalling model, with rate constants values coming from this study, a comparison between experimental mass change data and prediction has been shown. The hot corrosion study has provided new quantitative metal loss data and observations that extend/validate an existing model for materials life prediction, based on defining the severity of the corrosion conditions through measures of gas composition and contaminant deposition flux.
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Kovacs, Christopher Joseph. "Influence of Material Properties and Processing on Stability and Protectability in Superconducting Cables and Composites." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1574650528575944.
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Wright, J. D. "Impedance studies of water based protective coatings." Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386702.
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Mahajanam, Sudhakar P. V. "Application of hydrotalcites as corrosion-inhibiting pigments in organic coatings." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1123787459.
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Chadwick, Rennie. "Performance of concrete repair materials as corrosion protection for reinforcement." Thesis, University of Surrey, 1993. http://epubs.surrey.ac.uk/757/.
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Mansoori, Hamed. "Influence of Calcium and Magnesium Ions and their Carbonate Scales on CO2 Corrosion of Mild Steel." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1578414196892282.
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Pagnoncelli, Marlova. "Desenvolvimento de compósitos utilizando resina éster vinílica reforçada por fibra de aramida para aplicação em bindagem de veículos militares." reponame:Repositório Institucional da UCS, 2016. https://repositorio.ucs.br/handle/11338/1546.
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A moldagem por transferência de resina (RTM) consiste em um técnica de moldagem largamente empregada na indústria automotiva para obtenção de compósitos com elevadas propriedades específicas. Este trabalho tem por objetivo a obtenção de compósitos de alto desempenho obtidos a partir de resina éster vinílica reforçados por 4, 5 e 6 mantas de tecido de aramida (Kevlar 29) e caracteriza-los por ensaios de resistência à flexão, impacto, tração e cisalhamento interlaminar, densidade, volume de fibras e vazios, análise térmica dinâmicomecânica (DMTA), ensaio de compressão dinâmico a altas taxas de deformação utilizando a Barra Hopkinson Bi-Partida e impacto balístico. O tecido de aramida foi caracterizado por teor de umidade, TGA, FTIR e FEG-SEM. Durante a etapa de moldagem observou-se que o aumento do teor de fibras conferiu maior resistência ao fluxo de resina sobre o reforço, dificultando a molhabilidade das fibras mais distantes ao ponto de infeção, confirmado pelo teor de vazios de até 7%, nas bordas dos compósitos avaliados. De modo geral aumento do teor de reforço promoveu aumento das propriedades mecânicas. O compósito com 6 mantas de aramida (AD6) apresentou resistência ao impacto de 327 kJ/m², resistência a tração de 503 MPa, e resistência a flexão de 197 MPa. O aumento do teor de reforço resultou em melhores propriedades dinâmicas mecânicas, confirmadas pelo aumento do módulo de perda e de armazenamento e redução da altura do pico de tan delta. No ensaio de impacto Hopkinson o compósito AD6 apresentou maior tenacidade e tensão máxima. Devido às melhores propriedades mecânicas o compósito AD6 foi submetido ao impacto balístico, apresentando V50 de 302 m/s enquadrando-se no nível I de proteção balística. Tais resultados demostram que o RTM pode ser uma técnica promissora para confecção de compósitos a serem incorporados em blindagens multicomponentes.Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2017-02-07T12:40:37Z No. of bitstreams: 1 Dissertacao Marlova Pagnoncelli.pdf: 324904 bytes, checksum: 4648d428c0ce820b99cd5421ea03e7c0 (MD5)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.
The resin transfer molding (RTM) consists of a molding technique widely used in the automotive industry to obtain composites with high specific properties. This work aims to obtain high performance composites made with vinyl ester resin reinforced by 4, 5 and 6 aramid fabric (Kevlar 29) and characterize them by tests of flexural strength, impact resistance, tensile strength and interlaminar shear strength, density, fiber volume and voids, dynamic-mechanical thermal analysis (DMTA), dynamic compression at high shear rates using the Hopkinson Bi-Splice Bar and Ballistic Impact. Aramid tissue was characterized by moisture content, TGA, FTIR and FEG-SEM. During the molding step it was observed that the increase of fiber content increased the resistance to the resin flow through reinforcement, making it difficult to wet the fibers more distant to the injection point, confirmed by the voids content, that was up to 7%, in the edges of the evaluated composites. In general, the increase in the reinforcement content increased the mechanical properties of composite. The composite with 6 aramid fabrics (AD6) had impact strength of 327 kJ / m², tensile strength of 503 MPa, and flexural strength of 197 MPa. The increase in the reinforcement content resulted in better mechanical dynamics properties, confirmed by the increase of the modulus of loss and storage and reduction of the height of the delta peak. In the Hopkinson impact test the AD6 composite presented higher tenacity and maximum stress. Due to the best mechanical properties, the AD6 composite was subjected to ballistic impact, presenting a V50 of 302 m/s and a level I of ballistic protection. These results show that RTM can be a promising technique to produce composites to be incorporated into multicomponent shields.
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Lawson, K. "Corrosion monitoring and protective coating of reinforced concrete." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292460.
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