Дисертації: "Paper Effect of temperature on"

1

Elvin, Malin. "The effect of humidity and temperature on paper properties." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-54905.

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The study was performed at Billerudkorsnäs at the section Box Lab which offers knowledge and solutions for packaging. Paper that can be used to create packaging interacts with the surrounding environment, but has only been tested for a few climates. This thesis aims to investigate more climates and see how paper is affected by humidity and temperature and try to determine the cause of the results. The methods used to measure this was primary tensile test and moisture content analysis but also a test to evaluate creep was performed in climates with high humidity. From this, the mechanical properties of the paper were calculated. The test was performed in a climate chamber and the choice of methods was limited by what could be performed in the climate chamber. The materials tested were chosen to give a good representation of what is commonly used in the containerboard business. The climates for testing were selected from the ability of the climate chamber as well as interesting climates for the company. The results show that the papers are weakest at high RH, but the results indicate that the temperature solely impacts the properties of the paper. The highest moisture content does not necessarily mean the lowest value for a chosen property. The causes for the results are not clear since the patterns found are not bound to a certain quality but rather to paper in general. Therefore, more research on the area is suggested to try to determine what causes the material to react to temperature.

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2

Miroshnikova, Olga. "The Effect of Temperature on Lignin Degradation in Municipal Solid Waste." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/44891.

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Paper and paperboard are the major constituents found in US landfills. Typically paper consists of 79% to 98% of lignocellulose which is considered to be the most abundant source of natural carbon on earth. Lignocellulose decomposition depends on the association of biodegradable cellulose and hemicellulose with lignin. Lignin is a recalcitrant material which hinders cellulose degradation in conventional landfills. Because of this property of lignin cellulose to lignin ratio (C/L) is a common landfill stabilization parameter. Refuse degradation in landfills is a microbiological process and is highly dependent on temperature, moisture, and pH. Bioreactor landfills are designed to enhance biodegradation of refuse by providing favorable conditions for microorganisms. Effect of elevated temperature and moisture on possibility of lignin degradation is studied in this work. Synthetic and newspaper lignin were preheated and then inoculated with anaerobically digested sludge. Newspaper in distilled water exposed to 95Â°C for 48 hours released 8 times more of solubilized lignin then non preheated newspaper. Moreover lignin monomers were detected as a result of 95Â°C pretreatment indicating the positive effect of high temperature on the providing lignin in more bioavailable form for microbes. Digested sludge inocula was found to be capable of lignin monomers degradation as well as low but significant mineralization of synthetic lignin with approximately 6% of carbon originated from lignin mineralized into methane and carbon dioxide. An exponentially increasing trend for lignin monomers solubilization as a function of temperature was observed for three types of substrate, synthetic lignin, cardboard, and newspaper with the highest rate of solubilization for newspaper. Results of this study suggest that some lignin degradation can occur at conditions typical for bioreactor landfills.
Master of Science

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Kovara, Michael Anthony 1949. "The effect of temperature and overwater dissolved oxygen concentration on benthal feedback from pulp and paper mill sludges." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191913.

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Settleable solids accumulate (benthal layer) in stabilization lagoons, reducing volume for treatment and providing a source of oxygen demand and nutrients (feedback). The objective of this research was to define the impact of overwater dissolved oxygen (DO) and temperature upon these benthal properties. Batch benthal deposits (2:1, vol/vol, primary clarifier underflow and waste activated sludge) under a continuous-flow overwater layer were subject to variable temperature and DO. Experiment conditions simulated a facultative lagoon. Over 124 days, DO uptake was measured and effluent was sampled for chemical oxygen demand (COD), ammonia-N, and ortho-phosphate. Nearly all phosphorus feedback occurred in the first 31 days, and ammonia-N feedback was most constant for the duration. COD feedback was greatly reduced and DO uptake increased slightly with increasing DO. All feedbacks increased more from 15°C to 20°C than from 20°C to 26°C. Residual sludge analyses indicated that phosphorus was limiting to benthal stabilization. Temperature dependent reactions caused a linear decrease in total and volatile suspended solids.

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4

Hayakawa, N., T. Kobayashi, M. Hazeyama, T. Takahashi, K. Yasuda, and H. Okubo. "Partial discharge inception characteristics of LN/sub 2//polypropylene laminated paper composite insulation system for high temperature superconducting cables." IEEE, 2005. http://hdl.handle.net/2237/6846.

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Cunha, Kamyla Borges da. "Papel do Brasil, da Índia e da China Para a efetividade do regime climático pós-2012." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263831.

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Orientadores: Arnaldo Cesar Walter, Fernando Cardozo Fernandes Rei
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-16T08:10:47Z (GMT). No. of bitstreams: 1 Cunha_KamylaBorgesda_D.pdf: 6584850 bytes, checksum: f9cedaa0b7d809a1e7ca74de744ebb2c (MD5) Previous issue date: 2009
Resumo: A presente tese teve como objetivo principal analisar o papel de Brasil, Índia e China para a efetividade do regime climático pós-2012. Para tanto, foi preciso avaliar a efetividade do regime climático atual, perscrutar sobre os desafios da efetividade do futuro regime climático, identificar as principais semelhanças e diferenças entre o Brasil, a China e a Índia, em termos de contribuição para o efeito estufa adicional, analisar a posição oficial de cada um dos três países e perscrutar o papel desejável do Brasil no regime pós 2012. De modo a cumprir o objetivo proposto, realizou-se uma breve explanação sobre os aspectos científicos das mudanças climáticas, dando-se destaque para os desafios colocados a decisão política; fez-se uma analise do regime climático vigente, de modo a se identificar os principais aspectos foco da discussão sobre o futuro regime; procedeu-se a uma analise dos principais pontos de discussão sobre o regime climático pós-2012, com destaque para a efetividade ambiental do regime, a eficiência econômica e a equidade. Tais aspectos foram então avaliados sob a perspectiva política, de modo a destacar sua inserção na evolução das negociações internacionais. Buscou-se focar nos três países avaliados, levantando-se-lhes o perfil de emissões, energia e uso da terra, dados demográficos, econômicos e sociais, assim como sua postura política nas negociações internacionais. Realizadas todas essas analises, identificou-se a importância do Brasil, da China e da Índia para a efetividade do regime climático pós-2012, seja em função de sua crescente contribuição para as emissões de gases de efeito estufa, seja por forca de seu papel econômico, tanto no que diz respeito a distribuição dos custos de mitigação quanto ao cenário atual de crescente interdependência econômica. Também se constatou a ausência de correlação direta entre as emissões brasileiras de gases de efeito estufa e o desenvolvimento socioeconômico do pais, já que a maior parte decorre de desmatamentos ilegais. Entendeu-se que a postura brasileira há de focar-se nas oportunidades da assunção de compromissos voluntários relativos a redução das taxas de desmatamento
Abstract: This study aims at analyzing the role of Brazil, India and China for the of the international post-2012 climate change regime effectiveness. In order to meet this goal, it was necessary to evaluate the present climate regime effectiveness, to identify the main similarities and differences between Brazil, India and China, in terms of their contribution to greenhouse effect, to analyze their official position in the international negotiations and to evaluate the desirable role of Brazil in the post-2012 climate regime. The scientific aspects of climate change were briefly explored, in order to highlight the main challenges faced by the political decision. The present climate change regime was analyzed, in order to pose the main aspects of climate change discussion. The post-2012 climate regime effectiveness was posed in terms of wide participation of main countries and the need to bring together two main points: economic efficiency and equity. Then, the climate change international negotiation evolution was presented. After this general approach, this study has focused Brazil, India and China national circumstances, such as their greenhouse gases emissions profile, energy and land use sectors, demographic, economic and social indicators, as well their political position in the climate change international negotiations. As a result of such analysis, it was possible to identify the importance of Brazil, India and China for the post-2012 climate change regime effectiveness, first, because of their major contribution to greenhouse gases emissions, and second, because of their economic role, both in terms of mitigation costs distribution and in terms of the international economic interdependence. It was also identified the absence of direct relationship between Brazilian emissions and the country's socioeconomic development, considering that most of Brazil's emission come from illegal deforestation. It was concluded that Brazil could benefit in a scenario of position flexibility, assuming voluntary commitments related to deforestation reduction
Doutorado
Planejamento de Sistemas Energeticos
Doutor em Engenharia Mecânica

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6

Holmberg, Veronica. "Creating temperature stimulated paper muscles by printing and lamination." Thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11766.

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A paper that shows motion when being exposed to heat has in this study been called a paper muscle. A paper muscle can be used for many different applications, e.g. smart advertisement or indicators in printed paper products. The muscles created in the present work were prepared by gluing or printing a polymer layer onto paper. The polymer layers consisted of MELINEX, MYLAR or toner, which are known to expand when exposed to heat. Furthermore, all three material systems showed bending when exposed to heat.

A mechanical bilayer model was implemented and used to quantitatively study the parameters that influence the bending of the muscles. The model indicated that the dimensional changes of the polymer layers relative to that of the copy paper was found to be approximately 0,1-0,5 % within the temperature range 23-60 °C. The experiments showed that the combined dimensional changes within the polymer and paper layers were not linear with respect to temperature, and that there was a significant difference in bending for muscles cut in the MD and in the CD. Also, when assuming that the polymer is the active component, the observed coefficient of thermal expansion was a factor ~10 greater compared to published literature data. These findings led to the conclusion that it was indeed the dimensional changes within the paper that were the dominant cause of the bending. This was confirmed by a muscle, comprising a bilayer of paper cut in the MD and the CD, which bended when exposed to heat. The results also indicate that a large part of the bending could be attributed to the hygrocontraction of paper.

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7

Kumar, Pawan. "Effect of microwave drying on paper properties." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60711.

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Effects of microwave drying on the mechanical and optical properties of handsheets made from kraft and chemi-thermomechanical pulps were studied experimentally. The quality of paper dried in a microwave field of 2450 MHz is compared with that of paper dried by conventional method under standard conditions. Key physical properties measured include burst index, density, tear index, breaking length, zero-span tensile strength, double fold, STFI compressibility and optical properties include brightness, opacity and scattering coefficient. All properties were found to be either enhanced or at the same level as those obtained under standard conditions. Furthermore, it is suggested that microwave drying could replace the conventional drying method in the standard testing of pulp and paper samples for quality control purposes.

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Lieshout, Marit van. "The effect of wet-pressing on paper quality." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 2006. http://irs.ub.rug.nl/ppn/292620578.

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9

Okubo, H., H. Kojima, F. Endo, K. Sahara, R. Yamaguchi, and N. Hayakawa. "Partial Discharge Activity in Electrical Insulation for High Temperature Superconducting (HTS) Cables." IEEE, 2008. http://hdl.handle.net/2237/12061.

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10

Liu, Chung-Ni. "Laboratory investigation of the effect of the dampening solution on the loss of surface strength of coated paper /." Online version of thesis, 1993. http://hdl.handle.net/1850/11983.

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11

Byiringiro, Alfred. "Effect of paper mill ash on properties of expansive soils." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86287.

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Thesis (MEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Expansive soils, one of the problematic soils, are encountered on all continents with exception of polar continents. Problems caused by their heaving and shrinking behaviour, particularly to light structures, have been reported from different countries to place large financial burden on developers. For this reason, many techniques have been developed and applied to prevent and/or remediate the damage caused by these soils. Soil stabilization with traditional chemical additives has been applied successfully since ancient times. In addition to traditional additives such as lime, cement, fly ash, etc., some non-traditional additives, such as polymer based products, salts, etc. have been used effectively for soil treatment. On the other hand, industries are increasingly challenged by waste management in an acceptable and environmentally friendly manner. In this regard, a number of researches have been done on using industrial waste for soil improvement purposes. The study and understanding of basic reactions involved in lime-soil stabilization persuaded many researchers to study the applicability of lime-rich products for soil treatment. Studies conducted by Khalid et al. (2012); Muchizuki et al. (2004) and Thacker (2012) showed that lime-rich products such as pulp fly and bottom ashes and CaO by-products, can be applied for soil stabilization. This research was thus performed to investigate the effect of lime-rich paper mill waste ash on expansive soil properties. Two commonly listed soil engineering properties namely volume change and strength were investigated. Soil strength was examined in terms of unconfined compressive strength (UCS), due to its correlations with a number of other soil properties, and the volume change in terms of free swell and swelling pressure. In addition to these two engineering properties, dry density and moisture content were also studied due to their involvement in structural design, as well as gradation, Atterberg limits and California Bearing Ratio (CBR). The choice of these properties was also influenced by the availability of a standard (ASTM D4609-08) specifically developed to assess the effectiveness of admixtures for soil stabilization. Two main types of materials were used namely three clay materials and paper mill ash. According to the index properties, commonly used for expansive soil classification, three clays were classified into low, medium and high degrees of potential expansiveness. The ash results from the combustion of paper mill sludge, sawdust, bark, coal ash and bituminous coal in a multi-fuel boiler for the purpose of electricity and steam production. The tests mentioned above were conducted on both untreated and treated clays and the results were compared. Since the study was carried out on this material based on the fact that it contains lime, the procedure applied for lime-soil stabilization was considered. In general, it was observed that ash-soil treatment has a number of effects similar to lime-treatment and almost all studied properties were enhanced for all clays. It can thus be concluded that the paper mill ash from a multi-fuel boiler can be efficiently used for expansive soil treatment. For optimum use of this material for expansive soil treatment, more tests and further researches have been recommended.
AFRIKAANSE OPSOMMING: Uitsettende gronde, een van die probleemtipe-gronde, kom op alle kontinente voor, behalwe die twee poolkontinente. Probleme veroorsaak deur uitswellende en inkrimpende gedrag van hierdie gronde, veral finansiële onkostes van ligte strukture is al in baie lande aangemeld. Vir hierdie rede is baie tegnieke ontwikkel en toegepas om skade wat deur hierdie tipe gronde veroorsaak is, te voorkom en/of herstel. Hierdie tegnieke sluit grondstabilisasie met chemiese bymengsels in, veral tradisionele bymengsels, wat met groot sukses in die verre verlede toegepas en na moderne tye oorgedra is. Bykomend tot tradisionele bymengsels soos kalk, sement, vlieg-as ensovoorts is ŉ aantal nie-tradisionele bymiddels soos polimeergebaseerde produkte, soute en ander produkte ontwikkel vir grondstabilisasie. Aan die ander kant raak industrieë toenemend daarmee gemoeid om afvalstowwe op ŉ aanvaarbare en omgewingsvriendelike wyse te bestuur. Op hierdie gebied is ŉ aantal navorsingsprojekte al uitgevoer om industriële afval vir grondverbetering te gebruik en sodoende die las op nywerhede te verlig. Navorsing is onderneem om die basiese reaksies wat onstaan tydens stabilisasie van grond met tradisionele en moderne middels te bepaal en om die geskiktheid van kalkryke produkte vir grondstabilisasie te ondersoek. Baie navorsing is uitgevoer wat aangetoon het dat kalkhoudende produkte soos pulp vlieg- en oondresidu-as, asook CaO neweprodukte gebruik kan word vir stabilisasie. Gebaseer hierop is hierdie projek onderneem om die effek van papiermeulas, verkry deur die verbranding in ŉ veelvuldige brandstof-stoomketel, op die gedrag van uitsettende grond te ondersoek. Tydens hierdie studie is twee algemene ingenieurseienskappe van grond, naamlik sterkte en volumeverandering ondersoek. Grondsterkte is geëvalueer in terme van eenassige druksterkte (EDS) as gevolg van ? deur middel van die korrelasie met ŉ aantal ander grondeienskappe, en die volumeverandering in terme van vry-swel en sweldruk. Addisioneel tot hierdie twee grondeienskappe is droë digtheid en waterinhoud ook bestudeer aangesien beide in struktuurontwerp betrokke is. Verdere eienskappe wat ondersoek is, is gradering, Atterberggrense en Kaliforniese drakragverhouding (KDV). Die keuse van hierdie eienskappe is beïnvloed deur die beskikbaarheid van ŉ toetsstandaard (ASTM D4609-08) wat spesifiek ontwikkel is om die effektiwiteit van bymengsels vir grondstabilisasie te evalueer. Hierdie standaard is deurgaans as verwysing tydens die projek gebruik. Daar is waargeneem dat as-behandeling van grond ŉ aantal effekte het soortgelyk aan kalkbehandeling, met die uitsondering van die droë digtheid en optimum waterinhoud van een van die gronde wat getoets is. Byna al die eienskappe wat ondersoek is, soos EDS, KDV, ensovoorts, is verbeter behalwe in die geval van die eerste klei waarvan die plastisiteitsindeks verhoog het en die grond meer plasties geraak het. Daar kan dus afgelei word dat papiermeule-as vanaf ŉ stoomketel wat veelvuldige tipes brandstof gebruik geskik is vir die behandeling van uitsettende grond. Om die optimumgebruik van hierdie materiaal vir die stabilisasie van swellende klei te bepaal, is meer toetse en projekte nodig.

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12

Marsh, M. G. "The effect of a temperature gradient on high temperature fretting wear." Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267625.

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13

Zhou, Ya Jun. "The effect of ageing on alkyl ketene dimer sizing." Thesis, University of Manchester, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337537.

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14

Vorakunpinij, Adisak. "The effect of paper structure on the deviation between tensile and compressive responses." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/7058.

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15

Ankerfors, Caroline. "Polyelectrolyte complexes : their preparation, adsorption behaviour and effect on paper properties." Licentiate thesis, KTH, Fibre and Polymer Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4833.

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In this work, the formation of polyelectrolyte complexes (PECs) has been studied using a jet mixing method not previously used for mixing polyelectrolytes. The PECs were formed from two weak polyelectrolytes, i.e., polyacrylic acid (PAA) and polyallylamine hydrochloride (PAH), with different mixing times, and the results were compared with those for PECs formed using the conventional polyelectrolyte titration method.

The adsorption behaviour of the formed PECs on silicon oxide substrates and pulp fibres was analysed, and the results were compared with those for polyelectrolyte multilayers (PEMs) prepared from the same two polyelectrolytes.

The results indicated that by using the jet mixer, the size of the formed PECs could be controlled, which was not the case with the polyelectrolyte titration method. The PECs produced by jet mixing were also found to be smaller than those produced by polyelectrolyte titration. From these results, a two-step mechanism for the formation of PECs was suggested: initial precomplex formation, which is a fast and diffusion-controlled process, followed by a reconformation process, during which the vigorous mixing in the jet mixer can partially limit secondary aggregation.

When the complexes were adsorbed to silicon oxide or pulp fibre surfaces, adsorption studies indicated that it was impossible to reach the same adsorption levels for PECs as for PEMs. This was explained in terms of free energy, entropical, reasons rather than to any geometric limitation of the surface. Despite the smaller amount of polyelectrolyte adsorbed from the PEC treatment than from the PEM treatment of pulp fibres, the PEC treatment had the greatest effect on paper strength per adsorbed amount of polymer. This was thought to be because the three-dimensional structure of the PECs, versus the smoother structure of PEMs, allows for the formation of multiple contact points between the macroscopically rough fibres and increased molecular contact area.

In the adsorption experiments, it was also found that net cationic complexes can adsorb to both anionic and cationic substrates. This phenomenon was explained by the occurrence of anionic patches on the surface of the net cationic PECs and the ability of the PECs, formed from weak polyelectrolytes, to partially change charge upon exposure to a surface of the same charge as the complex itself, due to a change of the degree of dissociation of the polyelectrolytes constituting the complex.

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16

Lundberg, Anna. "Ink-paper interactions and effect on print quality in inkjet printing." Licentiate thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-13373.

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This thesis concerns paper and ink interactions related to inkjet printing. The main purpose of this work was to gain a deeper understanding in which parameters control the flow of ink into papers and how the ink interacts with the paper surface. The overall objective was to find key parameters to optimize the print quality in inkjet printing. Characterization of paper-surfaces in terms of porosity, surface roughness and surface energy was made. Objective and subjective measurements were used for print quality evaluation. Light microscopy imaging and SEM was used to see how ink interacts with the paper surface in a printed image. A high speed camera was used to study the absorption of picolitre sized inkjet droplets into fine papers. An initial study on the effect of paper properties on print quality was made. Result indicated that there were small differences in print quality for pilot papers with different composition (in a specific parameter window) and the commercial paper COLORLOK® reproduced a noticeable high colour gamut compared to the other samples.Research was made to see how surface fixation can affect the print quality for printouts made with pigmented ink. Surface fixation promotes retention of the pigmented colorant in the outermost surface layer of the paper and has been denoted “colorant fixation” in this thesis. It was shown that applying colorant fixation onto a paper surface before printing can increase the detail reproduction in a printed image. Different concentrations of calcium chloride were applied onto the paper surface on fullscale produced non-commercial papers. Test printing was made with a SoHo (Small office/Home office) printer using pigmented ink and results showed that using calcium chloride as surface treatment can lead to aggregation of pigments at the surface resulting in a higher detail reproduction. Fast absorption of the carrier liquid into the paper and fast fixation of colourants on the surface is important in inkjet printing to avoid colour to colour bleeding. These demands will be more pronounced when the printing speed increases. It is important to understand which parameters affect the absorption process to be able to control the mechanisms and to optimize the print quality. A study of absorption of picolitre size inkjet droplets into fine paper was made in this work. Theoretical equations describing fluid absorption into capillaries were tested and compared with experimental results. The result showed that the time dependence in the Lucas-Washburn (L-W) equation fits fairly well to data whereas the L-W equation overestimates the penetration depth. The results are directly applicable to paper and printing industry and can be used as a base for future studies of absorption of picolitre sized droplets into porous materials and for studies of aggregation of colloidal particles on surfaces.
Presentationen hölls den 2011-02-25
Next generation substrates for inkjet printing

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17

Motiee, Sima. "Effect of chemical additives on Z-direction filler distribution in paper." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44198.

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It is well known that paper properties such as opacity, printing quality, brightness, and roughness are affected by the z-direction mineral filler distribution. In this study, the effect of four different parameters (filler, starch, chemical retention aids and the machine parameter (vacuum)), on the z-direction filler distribution in paper samples was investigated. Paper samples were made using an apparatus that simulates a suction box. Different levels of filler (PCC), chemical additives and vacuum were chosen based on a central composite design. The effect of these parameters on filler distribution in cross-section of paper samples was investigated by using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray analysis (EDX) which is a non-destructive technique. The area covering the thickness of the paper was divided into five layers and each layer was subjected to EDX analysis to obtain the calcium content through the paper thickness. The results indicated that the filler distribution in the z-direction of paper samples increased from the top side to the wire side. The calcium content in the layer near the wire side was significantly higher than in the other layers. The other layers had similar calcium content. The chemical additives as well as vacuum in suction box had a significant effect on the filler distribution. Increasing the filler and starch led to higher level of filler content in all layers through the sheet thickness. Increasing the vacuum and retention aids led to higher level of filler content in layers near the wire side. The effect of high charge density starch used in our study was significantly higher than the effect of retention aids in retaining the filler through the thickness of the paper. Based on the obtained data, a set of empirical models were constructed that can predict the filler distribution through the thickness of the paper. We validated our results by measuring the calcium content through applying image processing technique on the SEM cross-section images and measuring the ash content of paper samples. The results of both of these approaches confirmed the EDX measurements.

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Poirier, Nicole A. "The effect of superheated steam drying on the properties of paper." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41057.

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The effect of drying paper by direct contact with superheated steam was determined with respect to the physical, optical and chemical properties of the dried sheet. The results were compared with those for paper dried in a similar fashion by direct contact with hot air.
It was found that the results depended on the type of pulp from which the sheet was made. For thermomechanical pulp sheets, superheated steam drying resulted in improved strength properties; burst index, tensile index and elastic modulus were 20-30% higher relative to the air dried sheets. The increase in strength was found to be due to an increase in bonded area, especially of the fine fraction, caused by the higher sheet temperatures occurring in the constant rate period of steam drying. As a result of the increased bonding but not due to any color change, brightness of the steam dried sheet decreased by 5 points. Steam drying of TMP sheets results in strength and optical properties more characteristic of paper made from CTMP.
Superheated steam drying of kraft pulp sheets had a smaller and opposite effect, as strength properties decreased and optical properties increased relative to the properties of sheets dried in air. Unlike mechanical pulp, no increase in bonded area was observed because of the already high bonding potential of kraft fibres; a thermally induced drying stress relaxation is thought to be the cause of the decreased strength properties.

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19

Zabbia, Alex. "The effect of protein loaded paper-board on milk flavour compounds." Diss., University of Pretoria, 2010. http://hdl.handle.net/2263/31341.

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20

Biniaris, Andreas. "Insight on the effect of contour height in pressure screening." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/754.

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The main purpose of this study was to determine the effect of contour height on the passage ratio of pulp through screen apertures, and determine which operating variable has the greatest affect on screen performance. In addition, a freeness model was to be developed, in hopes of helping to predict the freeness drop between feed and accepts. The study was conducted at The University of British Columbia (UBC) using a laboratory scale pressure screen. Slot velocity, feed consistency and contour height were the changing variables. Samples were collected from which passage ratio, freeness, fibre length and coarseness were determined. From the studies conducted it was found that slot velocity had the greatest influence on the screen operation. As the slot velocity increased a greater force was applied to the fibre to help push it through the screen aperture. However, this increase in slot velocity decreases the fractionation ability (separation of fibres into different lengths) of the screen. The second most important variable was the contour height. The main function of the contour height is to disrupt the flow of thick stock at the wall of the screen and allow for unhindered movement of fibre to the screen wall. The greater the contour height is, the greater the passage ratio (pulp fibre passing through screen). However, there is a decrease in fractionation. The third most important factor was the feed consistency. At low feed consistencies there is less crowding in the screen. Less crowding leads to more loosely-formed flocs, which are easier for the contour height and the rotor to dissipate and thus leads to unhindered movement. Thicker feed stock has a negative effect on passage A Freeness model was developed that showed that freeness had a power law relationship to passage ratio. The passage ratio was raised to a constant B, which is a function of the contour height and the feed consistency.

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21

Wajima, Takaaki. "Micro-porous Materials Synthesized from Paper Sludge Ash at Low Temperature, and its Chemical Mineralogy." Kyoto University, 2004. http://hdl.handle.net/2433/147718.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(人間・環境学)
甲第10960号
人博第247号
15||202(吉田南総合図書館)
新制||人||61(附属図書館)
UT51-2004-G807
京都大学大学院人間・環境学研究科文化・地域環境学専攻
(主査)教授玉田攻, 教授鎌田浩毅, 教授堀智孝
学位規則第4条第1項該当

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22

Lufitha, Mundel. "Effect of substrate temperature on coating adhesion." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58842.pdf.

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23

Mitchell, Angela. "The effect of temperature on starch synthesis." Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243060.

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24

Phillips, Lisa Elaine. "The effect of low temperature on Salmonella." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286534.

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25

Prasad, Renee Priya. "The effect of rearing temperature on performance of Trichogramma sibericum at ambient temperature." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51451.pdf.

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26

Lu, Xintong. "Print mottle of wood-containing paper, the effect of fines and formation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0004/NQ41218.pdf.

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27

Thomas, Zachary M. (Zachary Michael). "Dielectrometry measurements of moisture diffusion and temperature dynamics in oil impregnated paper insulated electric power cables." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40329.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Vita.
Includes bibliographical references (p. 439-449).
Paper insulated lead covered (PILC) cables have played an important role in underground power distribution for a hundred years. Replacing aged PILC before failure is critical to managing power distribution. Three prominent failure mechanisms accelerate cable aging: temperature stresses, moisture ingress, and partial discharge. The research focuses on the effect of temperature and moisture on the effective (complex) permittivity of the cable insulation. Measurements are performed using cylindrical dielectrometry sensors designed to be wrapped around the cable. The lead sheath of the cable is removed so that the sensors can be placed directly in contact with the insulation. From the measurements, the electrical properties of the material as a function of temperature and transient moisture diffusion are found. A theoretical treatment of the interdigital dielectrometry sensors with a cylindrical geometry is presented. Two classes of the geometry are studied. The periodic sensor geometry has electrodes aligned with the cylindrical axis and periodic around the circumference. The z periodic sensor geometry has the electrodes forming rings around the cylinder that are periodic along the cylindrical axis. The material is modeled by concentric rings of homogeneous materials. The electric field solution consists of an infinite summation of Fourier series terms. In finding the field solution and as a consequence of it, the potential, electric field lines, and the impedance between the driving and sensing electrodes are found. A generalized solution to the planar dielectrometry sensor topology is also presented. This solution allows for an arbitrary placement and excitation of electrodes, providing the analytical tools for a new generation of sensors.
(cont.) Dielectrometry sensors for use in and z periodic geometries are designed and manufactured on a 4 mil PTFE substrate. An experimental setup is designed and built to provide a temperature and humidity controlled environment for measurements. Special clamping mechanisms are used to secure the sensor to the sample. Custom built hardware is used to excite the sensor at frequencies ranging from 0.005 Hz to 10,000 Hz (over six decades), measure and record the response, and deliver it to a computer for storage and analysis. Steady state measurements are performed at temperatures ranging from room temperature to 100 C. Plastics, woods, and the PILC cable samples are measured. Using the theoretical model, the effective permittivity is estimated from the measurements. An Arrhenius temperature dependence is observed for several materials including the PILC cables. We characterize the temperature dependence of these materials by a master curve and activation energy. Together they give a complete description of the effective permittivity's frequency and temperature dependence. Transient measurements of moisture diffusion are made at constant temperatures for several materials. For some experiments the boundary conditions limit the diffusion of moisture to one direction. When the z periodic sensor is used, six independent measurements are taken along the direction of diffusion. From the initial and final conditions and the theoretical model, a mapping between the electrical properties and the insulation moisture content is formed. Moisture concentration along the direction of diffusion is estimated and in some cases characterized by a simple diffusion coefficient.
(cont.) The diffusion experiments provide evidence that moisture can move rapidly through the stranded conductors of the cables, delivering moisture to locations far removed from an initial breach. The experimental results show the electrical properties of the cable insulation is highly sensitive to the presence of moisture and changes in temperature. While using these sensors for field measurements may not be practical because they require the cable sheath to be removed, the technology provides a valuable, low cost tool for assessing cable health in an off-line setting.
by Zachary M. Thomas.
Ph.D.

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28

Ghaffarian, Niasar Mohamad. "Partial Discharge Signatures of Defects in Insulation Systems Consisting of Oil and Oil-impregnated Paper." Licentiate thesis, KTH, Elektroteknisk teori och konstruktion, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105785.

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Partial discharge measurement is a common method for monitoring and diagnostics of power transformers, and can detect insulation malfunctions before they lead to failure. Different parameters extracted from the measured PD activity can be correlated to the PD source, and as a result it is possible to identify the PD source by analyzing the PD activity. In this thesis, possible defects that could cause harmful PDs in transformers were investigated. These defects include corona in oil, a void in pressboard, a metal object at floating potential, surface discharge in oil, a free bubble in oil and small free metallic particles in oil. The characteristics of disturbing discharge sources were analyzed, like corona in air, surface discharge in air, and discharge from an unearthed object near to the test setup. The PD activity was recorded both in the time domain and phase domain, and possible characteristics for each PD pattern and waveform were extracted in order to find the best characteristic for the purpose of classification. The results show that in the phase domain parameters such as phase of occurrence, repetition rate and shape of PD Pattern are most suitable for classification while magnitude of discharge can only be useful in specific cases. The results show that the PD waveforms correlated to different defects are similar; however the time domain data include all the information from the phase domain, and also has the power to identify the number of PD sources. The PD dependency on temperature was investigated on the four test objects including surface discharges in oil, corona in oil, bubble discharges in oil, and metal object at floating potential. The effect of humidity was investigated for corona in oil. The results show that at higher temperature the corona activity in oil and PD activity due to a metal object at floating potential in oil decrease. However, for a bubble in oil and for surface discharge in oil the PD activity increases with the increase of the oil temperature. It was shown that the amount of moisture in oil has a strong impact on number of corona pulses in oil. The last part focused on ageing of oil-impregnated paper due to PD activity. Investigation was made of the behavior of PD activity and its corresponding parameters such as PD repetition rate and magnitude, from inception until complete puncture breakdown. The results show that both the number and magnitude of PD increase over time until they reach to a peak value. After this point over time both curves decrease slowly, and eventually full breakdown occurs. The effect of thermal ageing of oil impregnated paper on time to breakdown and PD parameters was investigated. The results show that thermal aging of oil-impregnated paper increases the number and magnitude of PD. Dielectric spectroscopy was performed on the samples before and after PD ageing and the result was used in order to explain the behavior of PD over time.

QC 20121129

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29

Sakaemura, Takushi. "Effect of distributions of polyacrylamide-based dry strength resin within paper and a fiber wall on development of strength properties of paper." Kyoto University, 2010. http://hdl.handle.net/2433/120914.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第15586号
農博第1836号
新制||農||984(附属図書館)
学位論文||H22||N4459(農学部図書室)
28107
京都大学大学院農学研究科森林科学専攻
(主査)教授木村恒久, 准教授山内龍男, 教授髙野俊幸
学位規則第4条第1項該当

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30

Kakireddy, Veera Raghava R. "Effect of temperature on copper chemical mechanical planarization." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0001973.

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31

Griškevičius, Mečislavas. "High Temperature Effect On Resistance Of Timber Structures." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101119_134602-29128.

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The present dissertation and its main subjects inquires into the pine and oak timber strength property changes-temperature relations. It also explores the behaviour of slender timber elements in axial compression at higher temperatures; and the comparative analysis of obtained results. The work seeks to accomplish the following major tasks: to obtain test data about the influence of high temperature on the properties of different natural – pine and oak – timber; to investigate the behaviour of slender timber elements under axial compression exposed to fire. Taking into account the investigated real fire effect to correct accordingly the existing in LST EN 1995-1-2 procedure for the fire resistance calculation of timber slender elements in compression. The dissertation consists of an introduction, five chapters, general conclusions, a list of references, a list of author’s publications on the dissertation subject, and 2 Annexes. Chapter 1 provides a literature review. It focuses on the publications inquiring into the loss of strength properties by timber at higher temperatures, the fire resistance of timber structures in compression. The chapter ends with the formulation of conclusions and the adjustment of research tasks. Chapter 2 offers the methodology of the research on strength properties of timber at higher temperatures, and the schemes of the developed testing equipment. Chapter 3 presents the procedure of the research on the behaviour of slender timber elements... [to full text]
Disertacijoje nagrinėjami pušinės ir ąžuolinės medienos stipruminių savybių pokyčių temperatūriniai sąryšiai bei medinių centriškai gniuždomų liaunų elementų elgsena veikiant aukštesnėms temperatūroms. Pagrindiniai tyrimo objektai yra Lietuvos spygliuočių ir lapuočių medienos savybių pokyčiai didėjant temperatūrai ir centriškai gniuždomų liaunų medinių elementų elgsenos veikiant kaitrai eksperimentiniai tyrimai bei rezultatų lyginamoji analizė. Darbe spręsti tokie pagrindiniai uždaviniai: gauti eksperimentinius duomenis apie aukštos temperatūros poveikį skirtingos natūralios – pušinės ir ąžuolinės – medienos savybėms, atlikti centriškai gniuždomų liaunų medinių elementų elgsenos ugnyje tyrimus. Atsižvelgiant į tyrinėtą tikrovišką gaisro poveikį patikslinti esamą EN 1995-1-2 medinių liaunų gniuždomų elementų atsparumo ugniai skaičiavimo metodiką. Disertaciją sudaro įvadas, penki skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai ir du priedai. Pirmasis skyrius skirtas literatūros apžvalgai. Jame pateikta darbų, kuriuose nagrinėjamas aukštesnės temperatūros veikiamos medienos, stipruminių savybių mažėjimas ir kuriuose pateikiami gaisro sąlygomis gniuždomų medinių elementų laikomosios galios tyrimų rezultatai. Pabaigoje formuluotos išvados ir disertacijos tikslai ir uždaviniai. Antrajame skyriuje pateikta medienos stipruminių savybių aukštesnėse temperatūrose tyrimo metodika ir sukurtų nestandartinių bandymo įrenginių schemos... [toliau žr. visą tekstą]

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32

Huang, Yan, and 黃燕. "Temperature dependent hall effect: studies ofGaN on sapphire." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B42577068.

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33

Harvey, Roy Edward. "The effect of high temperature on yeast fermentations." Thesis, Heriot-Watt University, 1988. http://hdl.handle.net/10399/1000.

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34

McGinnity, Frank A. "The effect of temperature on engine gas dynamics." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241518.

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35

Parks, Olivia Waverly. "Effect of water temperature on cohesive soil erosion." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/49663.

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In light of increased stream temperatures due to urbanization and climate change, the
effect of water temperature on cohesive soil erosion should be explored. The objectives of this study are to: determine the effect of water temperature on the erosion rates of clay; determine how erosion rates vary with clay mineralogy; and, explore the relationship between zeta potential and erosion rate. Samples of kaolinite- and montmorillonite-sand mixtures, and vermiculite-dominated soil were placed in the wall of a recirculating flume channel using a vertical sample orientation. Erosion rate was measured under a range of shear stresses (0.1-20 Pa) for a period of five minutes per shear stress at water temperatures of 12, 20, and 27ï¿½"C. The zeta potential was determined for each clay type at the three testing temperatures and compared to mean erosion rates. The kaolinite erosion rate doubled when the temperature increased from 12 to 20ï¿½"C, and erosion of vermiculite samples tripled when the temperature increased from 20 to 27ï¿½"C. The montmorillonite samples generally eroded through mechanical failure rather than fluvial erosion, and the limited fluvial erosion of the montmorillonite-sand mixture was not correlated with water temperature. The data suggest correlation between zeta potential and erosion rate; however, due to the small sample size (n=3), statistically significant correlation was not indicated. Research should continue to explore the influence of water temperature on cohesive soil erosion to better understand the influence of clay mineralogy. Due to the high degree of variability in cohesive soil erosion, multiple replications should be used in future work. The vertical sample orientation enabled discrimination between fluvial erosion and mass wasting and is recommended for future studies.
Master of Science

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36

Doluweera, D. G. Sumith Pradeepa. "Effect of Weak Inhomogeneities in High Temperature Superconductivity." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1227215152.

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37

Pack, Jessica Spencer. "Effect of Localized Temperature Change on Vigilance Performance." Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1429286666.

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38

Porter, Heidi S. "The effect of febrile temperature on Plasmodium falciparum /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2225.pdf.

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39

Takahashi, Junji 1951. "Effect of high temperature on lettuce seed development." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276828.

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More vegetable seeds are needed for developing countries to produce more vegetables. However, high temperature in these areas limits vegetable seed production. Leaf lettuce (Lactuca sativa L.) was grown in growth chambers at 21°C and exposed to different temperatures (28, 35, 38 and 42°C) for different exposure times (1, 4 and 7 hours) when flowers were at seven stages of development near anthesis.

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40

Porter, Heidi Sue. "The Effect of Febrile Temperature on Plasmodium falciparum." BYU ScholarsArchive, 2007. https://scholarsarchive.byu.edu/etd/1573.

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Previously it has been shown that cultures of Plasmodium falciparum died following exposure to a febrile temperature of 40°C, as demonstrated by a decrease in parasitemia of the following generation. In the current study, the effect of 40°C treatment on culture media, erythrocytes, and parasite glucose consumption, were ruled out as possible influences on parasite death, demonstrating that 40°C impacted the parasites directly. Metabolic profiling of DNA synthesis, protein synthesis, and glucose utilization during exposure to 40°C clearly indicated that febrile temperatures had direct effect on major metabolic pathways and parasite development, beginning 20-24 hr after erythrocyte invasion. The ring stages were relatively refractory to heat and recovered completely if returned to 37°C. The mechanism of parasite death was investigated for evidence of an apoptosis-like pathway in cells treated with 40°C, chloroquine, and staurosporine. Lack of typical physiological hallmarks, namely, caspase activation, characteristic mitochondrial membrane potential changes, and DNA degradation as indicated by DNA laddering, eliminated ‘classical’, apoptosis as a mechanism of parasite death. Parasites dying under the influence of 40°C, staurosporine, and chloroquine initially appeared pyknotic in light and electron microscopy, as in apoptosis, but eventual swelling and lysis of the food vacuole membrane led to secondary necrosis. Initially, chloroquine did induce DNA laddering, but it was later attributed to occult white blood cell contamination. While not apoptosis, the results do not rule out other forms of temperature-induced programmed cell death.

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41

Cornwell, Matthew Allen. "Determination of the bending stiffness of copy paper and its dependence on temperature and moisture using laser ultrasonic lamb waves." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/19636.

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42

Fouts, John Lyle. "Forming Screen Effect on Ultrasonic Beam Field." Thesis, Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/10423.

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The aim of this study was to characterize the interaction between a pulsed ultrasonic wave and a paper forming screen for potential development of a smart paper forming sensor to measure velocity profile of the forming jet as it impinges on the wire. To achieve this goal, a Signal-Processing DOP 2000 pulsed ultrasonic Doppler velocimeter was used to generate a pulsed ultrasonic signal. The signal was transmitted and received using four different ultrasonic transducers: a 2 MHz 10 mm, 4 MHz 5 mm, 4MHz 8 mm focused, and 8 MHz 5 mm. The ultrasonic signals were then analyzed in order to determine the ultrasonic beam echo amplitude and shape. These tests were performed with and without various paper forming screens placed between the ultrasonic transducer and an ultrasonic signal target. Two different paper forming screens were utilized to study the interaction of the ultrasonic beam with the forming screens. The tests showed that the ultrasonic signal passing through the forming screens is greatly attenuated causing a sharp decrease in echo amplitude. To overcome the attenuation of the signal, a much higher amplification of the signal was used causing an increase in the saturation region around the forming screen. This increased the minimum distance that a target had to be away from the forming screen. The closest distance from the plastic sphere to the screen over the widest range of transducer-screen-distances that produced detectable echoes was achieved with the 4 MHz 5 mm transducer. The tests showed for both screens that there is more variation in beam width when the screen is moved laterally than when it is not moved at all. They also show that even though the pores in the forming screen are very small, they seem to have a great effect on the beam width measurements of the ultrasonic transducer.

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43

Kiiza, Respicius Clemence. "Effect of HV Impulses on Partial Discharge Activity in Oil-Impregnated Paper Insulation." Licentiate thesis, KTH, Elektroteknisk teori och konstruktion, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-104829.

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High voltage (HV) transients in electrical power systems are mainly caused by lightning strikes and switching operations. The high voltage transient from its point of origin can propagate in either direction in the electrical power transmission line, and if its magnitude would be below the Basic Insulation Level (BIL) of the equipment for impulse voltage, it can reach the terminals of the equipment without being dissipated by surge arresters. The dielectric properties of a particular insulation at the instant of interaction with a high voltage transient would determine the level of the degradation of the electrical insulation caused by the high voltage transient. This thesis suggests on-line diagnostic techniques for monitoring the oil-impregnated paper condenser bushings by utilizing the naturally occurring HV transients in electrical power systems. The aim of the first experiment was to investigate the partial discharge (PD) characteristics of the PD defects which are likely to be found in oil-imregnated paper condenser bushings. In order to understand the condition at which the HV impulses would cause the change in phase resolved partial discharge (PRPD) patterns, four more experiments were performed. The second experiment was set in such a way that the effect of HV impulses alone could be investigated. On the other hand, the third experiment was set to examine the effect of PD-ageing at elevated AC voltage. The fourth experiment aimed in investigating the effect of combined PD-ageing at elevated AC voltage and the HV impulses. In order to investigate how different electrical stresses affect the dielectric properties of the oil-impreganted paper insulation, the fifth experiment about the dielectric spectroscopy (DS) in frequency domain was performed. The measurement results presented in this thesis show that high voltage impulses can have a large impact on the behavior of PRPD patterns if the test sample is aged by partial discharges, but a smaller impact when the test sample is unaged. The measurement results also show that the degradation of the oil-impregnated papers is much faster when the oil-impregnated papers are suffered from the combination of the HV impulses and the PD activity at elevated AC voltage than when they are suffered from the PD activity at elevated AC voltage alone.

QC 20121115

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44

Kirca, Onder. "Temperature Effect On Calcium Aluminate Cement Based Composite Binders." Phd thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607454/index.pdf.

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In calcium aluminate cement (CAC) systems the hydration process is different than portland cement (PC) systems. The hydration products of CAC are subjected to conversion depending on temperature, moisture, water-cement ratio, cement content, etc. Consequently, strength of CAC system can be seriously reduced. However, presence of other inorganic binders or additives may alter the hydration process and improve various properties of CAC based composites. The objective of this study is to investigate the temperature effect on the behaviour of CAC based composite binders. Throughout this research, several combinations of CAC-PC, CAC-gypsum, CAC-lime, CAC-ground granulated blast furnace slag (CAC-GGBFS) were studied. These CAC based composite binders were subjected to seven different curing regimes and their strength developments were investigated up to 210 days. In addition, the mechanism of strength development was examined by XRD analyses performed at 28 and 210 days. Finally, some empirical relationships between strength-time-curing temperatures were formulated. Experimental results revealed that the increase in ambient temperature resulted in an increase in the rate of conversion, thereby causing drastic strength reduction, particularly in pure CAC mix. It has been observed that inclusion of small amount of PC, lime, and gypsum in CAC did not induce conversion-free CAC binary systems, rather they resulted in faster conversion by enabling rapid formation of stable C3AH6 instead of metastable, high strength inducing CAH10 and C2AH8. On the other hand, in CAC-GGBFS mixes, the formation of stable straetlingite (C2ASH8) instead of calcium aluminate hydrates hindered the conversion reactions. Therefore, CAC-GGBFS mixes, where GGBFS ratio was over 40%, did not exhibit strength loss due to conversion reactions that occurred in pure CAC systems.

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45

Calmunger, Mattias. "Effect of temperature on mechanical response of austenitic materials." Thesis, Linköpings universitet, Konstruktionsmaterial, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-73748.

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Global increase in energy consumption and global warming require more energy production but less CO2emission. Increase in efficiency of energy production is an effective way for this purpose. This can be reached by increasing boiler temperature and pressure in a biomass power plant. By increasing material temperature 50°C, the efficiency in biomass power plants can be increased significantly and the CO2emission can be greatly reduced. However, the materials used for future biomass power plants with higher temperature require improved properties. Austenitic stainless steels are used in most biomass power plants. In austenitic stainless steels a phenomenon called dynamic strain aging (DSA), can occur in the operating temperature range for biomass power plants. DSA is an effect of interaction between moving dislocations and solute atoms and occurs during deformation at certain temperatures. An investigation of DSA influences on ductility in austenitic stainless steels and nickel base alloys have been done. Tensile tests at room temperature up to 700°C and scanning electron microscope investigations have been used. Tensile tests revealed that ductility increases with increased temperature for some materials when for others the ductility decreases. This is, probably due to formation of twins. Increased stacking fault energy (SFE) gives increased amount of twins and high nickel content gives a higher SFE. Deformation mechanisms observed in the microstructure are glide bands (or deformations band), twins, dislocation cells and shear bands. Damage due to DSA can probably be related to intersection between glide bands or twins, see figure 6 a). Broken particles and voids are damage mechanisms observed in the microstructure.

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46

Naperalsky, Michael E. "Effect of post-exercise environmental temperature on glycogen resynthesis." The University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-06052009-115319/.

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Hotter environments can often alter the normal exercises responses of metabolism and work performance compared to exercise in a more neutral condition. The goal of this study was to determine the effects of a hot (H) and room temperature (RT) environment on glycogen resynthesis during recovery from exercise. Recreationally active males (n = 9) completed two trials, each with 60-min of cycling exercise at 60% of maximum watts in a temperature-controlled chamber (32.6°C), followed by 4 hours of recovery at the same temperature (H) or 22.2°C (RT). Subjects were fed a carbohydrate beverage (1.8 g/kg bodyweight) at 0 and 2 hours post-exercise. Muscle biopsies were taken from the vastus lateralis at 0, 2, and 4 hours post-exercise for analysis of muscle glycogen. Blood samples were collected at 0, 30, 60, 120, 150, 180, and 240 minutes of recovery for glucose and insulin analysis. Ambient and core temperatures were monitored for the duration of the trial. Expired gas was collected prior to 2- and 4-hour biopsies for calculation of whole-body carbohydrate (CHO) oxidation. Glycogen, core temperature, CHO oxidation, and blood marker values were analyzed using two-way ANOVA with repeated measures. Average core temperature was significantly higher in H compared to RT (38.1°C ± 0.01° vs. 37.9°C ± 0.08°, p<0.05) during recovery. Glycogen was not different at 0 and 2 hours post-exercise. However, at 4 hours post-exercise muscle glycogen was significantly higher in RT vs. H (105 ± 28 vs. 88 ± 24 mmolkg-1 wet weight, respectively). Blood glucose levels were similar between H and RT for the first two hours, but showed lower values (p<0.05) in RT compared to H at time points 150, 180, and 240 minutes post-exercise. CHO oxidation during recovery was higher in H compared to RT (0.36 ± 0.04 g/min vs. 0.22 ± 0.03 g/min, respectively, p<0.05), with greater CHO oxidation at 4-hours post-exercise in both trials. Glycogen resynthesis during recovery is impaired in a hot environment, likely due to increased oxidation of CHO instead of synthesis.

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47

Salinas, Rodríguez Armando. "Effect of temperature on texture development in zirconium alloys." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75850.

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A theoretical and experimental study is presented of texture evolution in hcp zirconium deformed at high temperatures. It is shown that, within the temperature range in which nuclear components are fabricated, the development of crystallographic texture is controlled by the simultaneous activation of $ langle$a$ rangle$ and $ langle$c + a$ rangle$ slip. This is demonstrated by experiments on Zr-2.5 Nb and unalloyed Zr deformed along three of the four elementary strain paths: axisymmetric elongation and compression and pure shear. Further experimental work on the axisymmetric deformation of unalloyed Zr and Zr-20 Nb shows that the influence of the bcc $ beta$-Zr phase present in Zr-2.5 Nb at the temperatures of interest is not due to the formation of crystallographic textures in this phase.
Texture evolution modelling was implemented for the case of polycrystalline hcp metals by making use of the duality principle between the generalized Taylor and Bishop-Hill theories of polycrystal plasticity and with the help of linear programming. The high temperature experimental textures for the three elementary strain paths mentioned above were successfully predicted using the relaxed constraint theory. It is shown that, for the cases of pure shear and compression, the so-called pancake version of this approach gives a better approximation to the observed textures than the full constraint calculations. For axisymmetric elongation, the curling version of the relaxed constraint model gives the best results.
By the analysis of slip activity maps, it is shown that the limitations of the full constraint model reside in the high activity level for $ langle$c + a$ rangle$ slip associated with this approach. When the relaxed constraint model is applied, the activity level of $ langle$c + a$ rangle$ slip is considerably reduced, leading to much better agreement of the predicted textures with the experimental results. The full constraint model is also applied to simulate texture evolution in $ alpha$-Zr deformed in simple shear at room temperature. It is demonstrated that the level of agreement is at least as good as that obtained when full constraint calculations were carried out. Finally, a high temperature texture rosette is proposed for prediction of the textures developed during tube forming operations for Zr alloy nuclear components. (Abstract shortened with permission of author.)

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48

Williams, W. "The effect of time and temperature on magnetic remanence." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382523.

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49

Caunce, Maria. "The effect of age upon temperature regulation in humans." Thesis, Queen Mary, University of London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410037.

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50

Su, Yu Chu Joan. "The effect of interfacial phenomena on high temperature processes." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423096.

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