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Molik, Sabine. "Das plastidäre Rieske Fe/S-Protein Analyse des Transport- und Assemblierungsprozesses /." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975694057.
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Cornelsen, Sabine. "Bioinformatische Untersuchungen zur Evolution der Prokaryoten und Plastiden." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964592053.
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Drescher, Anja. "ycf1, ycf14 und RNA-Edierung." Diss., lmu, 2003. http://nbn-resolving.de/urn:nbn:de:bvb:19-13699.
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Materna, Arne Christian. "Development of molecular tools in the diatom Phaeodactylum tricornutum." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:352-opus-52997.
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Grosche, Christopher [Verfasser], and Uwe [Akademischer Betreuer] Maier. "Spezielle Leistungen der Plastide: RNA-Edierung in Landpflanzen, Genomreduktion und Proteinimport in Peridinin-haltigen Dinoflagellaten / Christopher Grosche. Betreuer: Uwe Maier." Marburg : Philipps-Universität Marburg, 2012. http://d-nb.info/1028072678/34.
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Pacheco, Túlio Gomes. "The complete plastid genome sequence of Passiflora cincinnata: genome rearrangements, massive plastid gene losses and implications to genome-plastome incompatibility." Universidade Federal de Viçosa, 2016. http://www.locus.ufv.br/handle/123456789/11539.
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A organização, ordem e conteúdo gênico de genomas plastidiais (plastomas) são bastante conservados em angiospermas, porém há exceções a esta regra. Este parece ser o caso do gênero Passiflora, pois há evidências de perdas não usuais de genes plastidiais para espécies deste gênero. Porém, nenhum plastoma de Passiflora foi publicado até o momento, o que dificulta estudos a respeito da evolução do plastoma deste grupo. Da mesma forma, o estudo das causas da incompatibilidade entre o genoma nuclear e plastoma, apresentada por alguns híbridos interespecíficos de Passiflora, tem se mantido obscuro devido à falta de sequências plastidiais disponíveis no banco de dados. Assim, visando começar a preencher estas lacunas e ainda permitir a caracterização de marcadores genéticos plastidiais e a construção de vetores para transformação plastidial em Passiflora, o presente trabalho teve como objetivo o sequenciamento, montagem, análise e caracterização do plastoma de Passiflora cincinnata. Os dados indicam uma massiva perda de genes plastidiais essenciais para a viabilidade celular (infA, rps7, rps16, rpl20, rpl22, ycf1 e ycf2), os quais, muito provavelmente, foram transferidos para o núcleo e seus produtos são importados pelos plastídios. Este genoma mostrou alta taxa de substituição de nucleotídeos para os genes accD e clpP. Apesar da alta divergência, a sequência traduzida destes genes mantém a maioria dos domínios funcionais previstos para as proteínas que codificam e com isso a funcionalidade dos mesmos não pode ser descartada. Além disso, múltiplas inversões também foram detectadas no plastoma de P. cincinnata, mudando a ordem de vários genes. Em conjunto, os dados sugerem uma incomum evolução do plastoma de P. cincinnata, caracterizada por perdas gênicas, inversões no genoma e presença de genes com aceleradas taxas de substituição de nucleotídeos. Assim, é possível sugerir que esta instabilidade do genoma e perda de genes essenciais possa estar relacionada com a incompatibilidade entre núcleo e plastoma observada em híbridos de Passiflora. Por fim, a sequência completa do plastoma de P. cincinnata, obtida neste trabalho torna viável a transformação plastidial nesta espécie, visando aplicações biotecnológicas, além de estudos evolutivos e de genética funcional.
The plastid genome (plastome) organization, gene content and order is well conserved in most angiosperms, but there are some exceptions. The Passiflora genus is one of those exceptions, because there are evidences of some unusual plastid gene losses to species of this genus. However, none plastome of Passiflora has been published to date, making studies related to the evolution and putative high instability of plastome in this group difficult. In parallel, the study of the causes of nucleus-plastome incompatibility, observed in interspecific hybrids of Passiflora, has remained obscure due to the lack of plastid sequences in the database. In the context, starting to fill these gaps and to enable the characterization of plastid genetic markers and the construction of vectors for plastid transformation in Passiflora, the aim of the present study was the sequencing, assembly, analysis and characterization of complete P. cincinnata plastome. The data indicate a massive loss of plastid genes that are essential for cell viability (infA, rps7, rps16, rpl20, rpl22, ycf1 and ycf2), which very likely were functionally transferred to the nucleus and its products are imported into plastid. This genome also showed a high rate of nucleotide substitution in several genes, such as accD and clpP. Despite this high divergence, the translated amino acid sequences of these genes retain most of functional domains predicted indicating that they can still encode functional proteins. In addition, multiple inversions were detected in the P. cincinnata plastome, changing the order of several genes. Taken together, the data suggest a markedly uncommon evolution of P. cincinnata plastome, characterized for gene losses, multiple inversions and genes with accelerated nucleotide substitution rates. Thus, it is possible to suggest that the genomic instability and essential genes losses, observed here, may be related to the genome- plastome incompatibility observed in Passiflora hybrids. This relation can be established and investigated of an accurate manner with the sequencing of other Passiflora plastomes. Finally, the complete plastome sequence of P. cincinnata obtained in this work enables the plastid transformation to this species, aiming biotechnology applications and studies of evolution and functional genetics.
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LINDSTRAND, NILS, and KARL THUNELL. "From Plastic to Paper Mapping the real cost of plastics." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-224931.
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Al-Ati, Tareq. "Oxygen permeation of virgin HDPE films versus recycled HDPE films /." Online version of thesis, 1994. http://hdl.handle.net/1850/11875.
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Doshi, Shailesh R. "A novel coextrusion process for the manufacture of short fiber-reinforced thermoplastic pipe /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72817.
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Pitteri, Silvio. "Processing and evaluation of filled thermoplastics." Thesis, Brunel University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253309.
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Sævik, Svein. "On stresses and fatigue in flexible pipes." Norway : Dept. of Marine Structures, the University of Trondheim, 1992. http://catalog.hathitrust.org/api/volumes/oclc/27348152.html.
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Dura, Matthew Jonathon. "Behavior of Hybrid Wood Plastic Composite-Fiber Reinforced Polymer Structural Members for Use in Sustained Loading Applications." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/DuraMJ2005.pdf.
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Bodalia, Raj. "An investigation of the "walking" behavior in the manufacturing of biaxially oriented polypropylene films /." Online version of thesis, 1988. http://hdl.handle.net/1850/10691.
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Aw, Cheong Soon (Samuel). "A study to evaluate the permeation characteristics of black tea flavors and linalool in four different plastic films /." Online version of thesis, 1995. http://hdl.handle.net/1850/11853.
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Kasichainula, Nagesh. "Mechanic characterization of reinforced rigid polyurethane foams /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418038.
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Strand, Seth R. "Effects of Friction Stir Welding on Polymer Microstructure." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd338.pdf.
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Vainstein, Jimmy. "A study of the conditions and variables that affect the printing of shrink films on waterbased flexography /." Link to online version, 2005. https://ritdml.rit.edu/dspace/handle/1850/1107.
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Souza, Benjamin J. "Fracture Mechanics Characterization of WPC-FRP Composite Materials Fabricated by the Composites Pressure Resin Infusion System (Compris) Process Volume I (Chapters 1-7, Appendix A)." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/SouzaBJ2005.pdf.
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Bačiulis, Mindaugas. "Plastiniai menai interneto svetainėse." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060118_125053-93582.
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Kaartinen, Johanna. "A Checklist for Plastic Product Design: Preventing Pitfalls in a Design Process and Premature Failures of Plastic Products." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-9683.
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Designing an injection molded plastic part requires optimizing the part with respect to various stakeholders’ needs throughout its life cycle. The conditions in which a product is operating in service are often inadequately understood or specified, resulting in wrong material selection, which in turn leads to failure when the product is used. Many aspects interrelate with the initial part design and the essential rules of each should be taken into account to ensure a well-functioning plastic product. Regardless, a part design often passes sequentially from concept development to the manufacturing phase with features that unnecessarily complicate production, add costs and weaken the intended embodiment of the product. Therefore, a checklist was developed to ensure that oversights do not happen and verify that a design fulfills the requirements set for it. The commissioning company in the project was the design office Sytyte Oy. The aim of this thesis work was to investigate the effects of design decisions on the product’s feasibility and performance in service. The study focused on the underlying reasons for failures in plastic products, failure phenomena and ways of preventing them. The project started with literature research. To support the theoretical review, a small-scale survey was conducted among operators in plastic industry in Finland to strengthen the outcome of the project. The findings from the research were compiled into a checklist. The approach into the list was adopted from the FMEA method aiming to create a stripped-down version of it. The result offers a tool for anticipating and spotting possible failures by bringing up the influences that most frequently affect the part performance. It contributes to preventing delays in processing and premature failures in service. The checklist was verified by specialist consultation to receive suggestions and requirements for improvements and to ensure its reliability.
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Moran, Matthew T. "Testing the predictability of water-based flexographic inks on plastic substrates /." Online version of thesis, 1993. http://hdl.handle.net/1850/11271.
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Ruan, Haihui. "Collision between two perfectly plastic beam structures : modeling and verification /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?MECH%202004%20RUAN.
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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2004.Includes bibliographical references (leaves 235-241). Also available in electronic version. Access restricted to campus users.
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McDonald, Seonaidh. "The management of post-consumer plastics waste recycling in the UK." Thesis, University of Stirling, 1996. http://hdl.handle.net/1893/1786.
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This thesis examines the management of post-consumer plastics waste recycling in the UK. It brings together information and approaches from a number of disciplines in order to present a comprehensive view of the post-consumer plastics waste recycling industry and provide insight into participation issues. Two Scottish collection schemes are utilised as case studies throughout. The thesis summarises current practice in post-consumer plastics recycling and describes the processes associated with it. It also presents a summary of legislation relevant to plastics recycling in the UK, EC and US in particular. The thesis includes a quantitative survey of 500 members of the public that analyses their recycling behaviour and factors that affect motivation. It also looks at public perceptions of plastics. This is complemented by a qualitative study of plastics recyclers that examines recycling routines in more detail, and explores issues that affect the participation, and quality of donation, of individuals. The evaluation of post-consumer plastics recycling schemes is discussed, and models are developed in order to assessth eir financial viability. The lessons gained from this programme of research are then summarised in a policy framework.
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Adi, Riyono Winarputro. "CJS-RE : a hierarchical constitutive model for rammed earth." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEC036/document.
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Le pisé est une technique constructive vernaculaire consistant à compacter successivement des couches de terre humide entre des coffrages. Cette technique, présente dans le monde entier, l'est en particulier en France dans la région Auvergne-Rhône-Alpes. Comme il n'existe pas de réglementation attachée à cette technique constructive, il est très difficile pour des propriétaires de réparer leur bien. Le développement de cette technique pour de nouveaux projets souffre aussi de cette absence alors qu'elle répond à certains enjeux posés par le Développement Durable. Le travail présenté ici fait partie intégrante du projet national PRIMATERRE dédié à l'étude des constructions impliquant de la terre. Une loi de comportement élasto-plastique est développée dans ce travail pour modéliser le comportement du pisé. Elle s'appuie sur une approche hiérarchisée de la modélisation en lien avec le nombre d'essais disponibles pour identifier les paramètres de modèle mais aussi en lien avec la complexité de phénomènes à prendre en compte. Ce modèle s'inspire d'un modèle pré-existant, CJS, développé en géotechnique pour modéliser le comportement mécanique des matériaux granulaires. Une adaptation s'est imposée pour prendre en compte les spécificités du comportement mécanique du pisé qui possède de nombreuses similitudes avec celui des matériaux quasi-fragiles. Deux niveaux de modélisation pour le modèle de comportement appelé CJS-RE sont présentés, pouvant être utilisés dans un contexte de sollicitation monotone. Le premier niveau CJS-RE1 est un modèle élastique parfaitement plastique alors que le second niveau CJS-RE2 est un modèle élasto-plastique à écrouissage isotrope. Deux mécanismes de déformation plastique sont présents, l'un lié aux phénomènes purement déviatoires et l'autre aux phénomènes de traction. La validation du modèle a été entreprise sur la base de la simulation d'essais en laboratoire de compression diagonale et de chargement latéral (pushover) sur des murets, issus de la littérature. Le niveau CJS-RE1 a été capable de capturer les phénomènes essentiels issus de ces deux tests et peut être utilisé comme une première approches des problèmes. Le niveau CJS-RE2 a permis de retrouver plus précisément le comportement non linéaire du pisé sur une large gamme de déformations, que ce soit dans l'essai de compression diagonale ou dans le pushover. Enfin, la prise en compte d'interfaces entre les couches dans la modélisation semble constituer une approche surdimensionnée lorsque seule la résistance d'un système constitué en pisé est recherchée. Cependant, parce qu'elles apportent une certaine ductilité au système dans la modélisation, elles peuvent être utilisées lorsque des résultats plus détaillés sont attendusRammed earth is a vernacular building technique consisting in compacting successively layers of moist earth within formworks. This technique is present worldwide and in particular in the region Auvergne-Rhône-Alpes in France. As no regulation exists for rammed earth structures in France, the owners of such structures are helpless at the time when repairing damages appearing in any aging heritage structures. Moreover, this lack of regulation tends to slow down the development of such a constructive solution in new projects though this technique answers many of the issues raised by the sustainable development. The work presented herein is part of the national research project PRIMATERRE devoted to the study of construction building involving earth. Herein, an elasto-plastic constitutive law is developed for modeling the behavior of rammed earth. It is based on a hierarchical approach of the modeling in relation to the information available to identify the set of model parameters and the refinement of phenomena to be modelled. This model was adapted from a pre-existing CJS model used in advanced foundation engineering for the modelling of granular soils. The necessary adaptation of some mechanisms of the model in the context of rammed earth material which holds the characteristics of a quasi-brittle material is highlighted. Two levels for the model denoted CJS-RE which can be used in the context of monotonous loadings are presented herein. The first level is a simple elastic perfectly plastic model (CJS-RE1) and the second model is an elasto-plastic model with an isotropic hardening (CJS-RE2). Two mechanisms of plastic deformation are involved, one related to purely deviatoric phenomena and one related to tensile phenomena. The validation of the model was performed based on different sets of actual tests including diagonal compression tests and pushover tests on wallets. The simple elasto-plastic model CJS-RE1 was able to capture some basic features for these two tests and may be used for a first estimate of the system resistance. The more sophisticated model CJS-RE2 was found better to retrieve the nonlinear behavior of rammed earth over a larger range of deformations throughout both a diagonal compression test and a pushover test. Finally, the modelling of interfaces between layers of earth seems oversized when the resistance of the system is investigated. However, since they may influence the simulated ductility of the system, they may be used to model the behavior of rammed earth system more precisely
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Buys, Alexander George. "Performance evaluation of aluminium alloy 7075 for use in tool design for the plastic industry." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/1246.
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Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2009.The objective of this project was to measure the performance of high-strength aluminium alloys as injection mould material compared against conventionally used tool steel.
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Ponce, Toledo Rafael Isaac. "Origins and early evolution of photosynthetic eukaryotes." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS047/document.
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Les plastes primaires proviennent d'une cyanobactérie qui a établi une relationendosymbiotique avec un hôte eucaryote. Cet événement a donné naissance au super-groupeArchaeplastida qui inclut les Viridiplantae (algues vertes et plantes terrestres), les Rhodophyta (alguesrouges) et les Glaucophyta. Suite à l'endosymbiose primaire, les algues rouges et vertes ont étendu lacapacité de photosynthèse à d'autres lignées eucaryotes via des endosymbioses secondaires. Bien quedes progrès considérables aient été réalisés dans la compréhension de l'évolution des eucaryotesphotosynthétiques, d'importantes questions sont restées ouvertes, telles que l’identité de la lignéecyanobactérienne la plus proche des plastes primaires ainsi que le nombre et l'identité des partenairesdans les endosymbioses secondaires.Ma thèse a consisté à étudier l'origine et l'évolution précoce des eucaryotes photosynthétiques enutilisant des approches phylogénétiques et phylogénomiques. Je montre par mon travail que les plastesprimaires ont évolué à partir d'un symbiote phylogénétiquement proche de Gloeomargarita lithophora,une cyanobactérie représentant un clade s’étant diversifié précocement et qui a été détectéeuniquement dans les milieux terrestres. Ce résultat fournit des pistes nouvelles sur le contexteécologique dans lequel l'endosymbiose primaire a probablement eu lieu. En ce qui concerne l'évolutiondes lignées eucaryotes avec des plastes secondaires, je montre que les génomes nucléaires deschlorarachniophytes et des euglénophytes, deux lignées photosynthétiques avec des plastes dérivésd'algues vertes, encodent un grand nombre de gènes acquis par transferts depuis des algues rouges.Enfin, je mets en évidence que SELMA, la machinerie de translocation des protéines à travers laseconde membrane externe des plastes rouges secondaires à quatre membranes, a une histoireétonnamment compliquée aux implications évolutives importantes : les cryptophytes ont recruté unensemble de composants de SELMA différent de ceux des haptophytes, straménopiles et alvéolés.Ainsi, ma thèse a permis d’identifier pour la première fois la lignée cyanobactérienne la plus proche desplastes primaires et apporte de nouvelles pistes pour éclaircir les événements complexes qui ontjalonné l’évolution des eucaryotes photosynthétiques secondairesPrimary plastids derive from a cyanobacterium that entered into an endosymbioticrelationship with a eukaryotic host. This event gave rise to the supergroup Archaeplastida whichcomprises Viridiplantae (green algae and land plants), Rhodophyta (red algae) and Glaucophyta. Afterprimary endosymbiosis, red and green algae spread the ability to photosynthesize to other eukaryoticlineages via secondary endosymbioses. Although considerable progress has been made in theunderstanding of the evolution of photosynthetic eukaryotes, important questions remained debatedsuch as the present-day closest cyanobacterial lineage to primary plastids as well as the number andidentity of partners in secondary endosymbioses.The main objectives of my PhD were to study the origin and evolution of plastid-bearing eukaryotesusing phylogenetic and phylogenomic approaches to shed some light on how primary and secondaryendosymbioses occurred. In this work, I show that primary plastids evolved from a close relative ofGloeomargarita lithophora, a recently sequenced early-branching cyanobacterium that has been onlydetected in terrestrial environments. This result provide interesting hints on the ecological setting whereprimary endosymbiosis likely took place. Regarding the evolution of eukaryotic lineages with secondaryplastids, I show that the nuclear genomes of chlorarachniophytes and euglenids, two photosyntheticlineages with green alga-derived plastids, encode for a large number of genes acquired by transfersfrom red algae. Finally, I highlight that SELMA, the translocation machinery putatively used to importproteins across the second outermost membrane of secondary red plastids with four membranes, has asurprisingly complex history with strong evolutionary implications: cryptophytes have recruited a set ofSELMA components different from those present in haptophytes, stramenopiles and alveolates.In conclusion, during my PhD I identified for the first time the closest living cyanobacterium to primaryplastids and provided new insights on the complex evolution that have undergone secondary plastid-bearing eukaryotes
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Bakhach, Youssef. "Plasties d'opposition du pouce : analyse statistique et description d'une nouvelle technique de transfert tendineux." Bordeaux 2, 1992. http://www.theses.fr/1992BOR23036.
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Choy, M. K. "Plastid protein synthesis and plastid-to-nucleus signalling." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597661.
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Two plastid-to-nucleus signalling pathways had previously been identified by studies on genomes uncoupled (gun) mutants of Arabidopsis. Five putative gunl-like mutants from a new collection of Arabidopsis gun mutants with a green fluorescent protein (GFP) marker gene under the control of a tobacco RbcS (encoding ribulose-1,5-bisphosphate carboxylase small subunit) promoter were examined further. One of the mutant lines, PR48.2N, showed two-fold higher transcript abundance of nuclear photosynthesis genes, RBCS and LHCB1 (encoding light-harvesting chlorophyll a/b-binding protein 1), compared to wild type with or without treatments of norflurazon or lincomycin. Pigment analysis of PR48.2N seedlings, illuminated for 16 hours after being subjected to various lengths of dark treatment demonstrated that the mutant line accumulated less chlorophyll than wild type after short periods of darkness (2-4 days) but showed an enhanced ability to green after prolonged dark treatments (5-10 days). Consistent with the enhanced greening ability, transcript abundance of nuclear photosynthesis genes was higher and there was more thylakoids membrane in chloroplasts in greened PR48.2N seedlings after prolonged darkness compared to the wild type. Microarray analysis indicated that a group of transcripts encoding seed storage proteins, oleosins and late embryogenesis abundant proteins showed very low abundance in PR48.2N seedlings. The promoter regions of the genes shared some cis-elements possibly involved in regulation by ascisic acid (ABA). However, the ABA content of PR48.2N seedlings was not significantly different to wild type, although the germination of mutant seeds was more sensitive to inhibition by ABA than the wild type.
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Jradi, Layal. "Study of the influence of fine particles on the properties of liquefaction of sands." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1053/document.
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Au cours des 50 dernières années, l’étude du phénomène de liquéfaction de sols sableux saturés ont fait l'objet de nombreuses recherches en laboratoire. La plupart de ces recherches antérieures se sont concentrées sur la liquéfaction de sables propres, en supposant que la présence de fines limite le développement de la surpression interstitielle et donc le risque de liquéfaction. Cependant, les sables sableux naturels se trouvent généralement dans la nature sous la forme d'un mélange de sable et de fines et, l’influence de ces fines sur le risque de liquéfaction de ce type de matériau n'est toujours pas claire. En effet, on trouve des résultats contradictoires, dans la littérature, sur l'effet des particules fines sur le phénomène de liquéfaction des sables. Dans ce contexte, l’objectif principal de ce travail expérimental est de clarifier et de quantifier l’influence des particules fines présentes au sein d’une matrice sableuse sur l’initiation et le développement du phénomène de liquéfaction. On s’est intéressé, en particulier, à la nature des particules fines (plastique/non-plastique), à leur proportion au sein de la matrice, à l’état de compacité de la matrice et à l’état de contrainte initial (état de consolidation). A cet effet, à l'aide d'un nouveau dispositif triaxial servo-hydraulique, une série d'essais monotones et cycliques ont été effectués afin de clarifier cet effet. Les résultats expérimentaux montrent que l'augmentation de la proportion de fines non plastiques augmente la résistance à la liquéfaction du mélange sous chargements monotone et cyclique. Par contre, cette tendance est inversée pour les mélanges qui contiennent des fines plastiques. Enfin, une comparaison a été établie entre le comportement de ces sols sous cisaillement monotone et cyclique non drainé en termes d'évaluation du déclenchement du phénomène d'instabilité et d'autres paramètres mécaniquesSince the last 50 years, the study of the phenomenon of liquefaction of saturated sandy soils has been a topic of extensive laboratory research. Most of the earlier research has focused on the liquefaction of clean sands assuming that the presence of fines resists the development of pore water pressure as well as the risk of liquefaction. However, natural sand is found in nature under the form of a mixture of sand and fines and, the influence of these fines on the liquefaction risk of this type of material is still unclear. In fact, we could find contradictory results in the literature review of the effect of fine particles on the sand liquefaction phenomenon. In this context, the main objective of this study is to clarify and quantify the influence of fine particles (plastic and non-plastic) present in a sandy matrix on the initiation and development of the liquefaction phenomenon .We’ve focused, in particular, on the nature of fine particles (plastic/non-plastic), their proportion in the matrix, the matrix compactness condition and initial stress state (state consolidation). For this purpose, with the aid of a new triaxial servo-hydraulic device, a series of monotonic and cyclic tests were done in order to clarify this effect. Experimental results show that the increase in non-plastic fines increases the resistance to liquefaction of the mixture under both monotonic and cyclic loading. However, this trend is reversed for the mixtures containing plastic fines. Finally a comparison has been established between the behavior of these soils under undrained monotonic and cyclic shearing in terms of evaluation of the initiation of instability phenomenon and other mechanical parameters
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Coelho, Rivaldo Teodoro. "Contribuição ao estudo da aplicação de materiais alternativos nos compositos a base de cimento Portland : uso de grãos de polipropileno reciclado em substituição aos agregados do concreto." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258509.
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Orientador: Vitor Antonio DucattiDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
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Resumo: O principal objetivo desta dissertação foi a determinação das principais propriedades mecânicas de um compósito à base de cimento Portland CP-V-ARI (alta resistência inicial) tendo como agregado os grãos reciclados aglutinados de polipropileno (GRAP). A escolha do plástico se deve ao fato de que é um dos principais materiais utilizados pela indústria em geral sendo descartado em média na proporção de 7% do peso e 25% do volume do lixo urbano metropolitano e índice de reciclagem de 17,5%. No caso específico do polipropileno a proposta de seu uso deveu-se ao fato dele ser um dos três plásticos mais consumidos e descartados no Brasil, tornando-se oportuno o desenvolvimento de alternativas para a reciclagem deste material como material para a construção civil como agregado para o concreto. Neste estudo, foram realizados ensaios com base nas normas da ABNT ¿ Associação Brasileira de Normas Técnicas, para a caracterização do concreto no estado endurecido, principalmente para a determinação das resistências à compressão axial e diametral, resistência à tração na flexão e módulo de elasticidade secante. Os resultados obtidos em ensaios com misturas com e sem agregados minerais (substituição) foram satisfatórios permitindo o desenvolvimento de vários concretos com resistência à compressão axial (fcj) adequado para a produção de elementos pré-fabricados, concretos porosos adequados para drenagens e enchimento de lajes, painéis, blocos de concreto e grãos de polipropileno mineralizados com a pasta de cimento, dentre outras aplicações. Houve uma redução superior a 30% do peso final do concreto por meio da redução da massa específica. O novo concreto também se mostrou extremamente dúctil, adequado para especificações de absorção de impactos. Através dos resultados desta pesquisa pôde-se concluir que é perfeitamente viável o uso do concreto com grãos de polipropileno em substituição aos agregados minerais na construção civil
Abstract: The main objective of this dissertation was the determination of the main mechanical properties of a composite based on Portland cement CP-V-ARI (high initial resistance) tends as aggregate the grains recycled agglutinated of polypropylene (GRAP). The choice of the plastic is due to the fact that it is one of the main materials used by the industry in general being discarded on average in the proportion of 7% of the weight and 25% of the volume of the metropolitan urban garbage and index of recycling of 17,5%. In the specific case of the polypropylene the proposal of his use was due to his fact to be one of the three plastics more consumed and discarded in Brazil and that indicators reveal the need to develop alternatives for the recycling of this material in the engineering and in the building site as an aggregate for the concrete seeking the partial or total substitution of minerals aggregates. In this study, rehearsals were accomplished with base in the norms of ABNT - Brazilian Association of Technical Norms, for the characterization of the concrete in the hardened state, mainly for the determination of the resistances to the axial and diametrical compression, resistance to the traction in the flexing and module of drying elasticity. The results obtained in rehearsals with mixtures with and without aggregates minerals (substitution) they were satisfactory allowing the development of several concretes with resistance to the axial compression (fcj), through appropriate mixtures to the production of prefabricated elements, an appropriate porous concrete for drainages and stuffing of flagstones and polypropylene grains mineralized with the cement paste, among other applications. There was a superior reduction to 30% of the final weight of the concrete through the reduction of the specific mass. The new concrete was also shown extremely ductile, appropriate for specifications of absorption of impacts. Through the results of this research it could be concluded that it is perfectly viable the use of the concrete with polypropylene grains in substitution to the mineral aggregates in the building site
Mestrado
Edificações
Mestre em Engenharia Civil
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Li, Tao. "New compatibilizing agents for blends of linear low-density polyethylene and polystyrene as model systems of the post-consumer plastic waste stream." Case Western Reserve University School of Graduate Studies / OhioLINK, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=case1061478646.
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Maffei, Douglas P. F. "Identification of genes affecting plastid biogenesis and plastid-nuclear signalling." Thesis, Royal Holloway, University of London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.549584.
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Liu, Zheng. "Manipulation of plastid morphology and analysis of plastid gene expression." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430514.
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Busillo, Eric. "Characterization of plastic hypodermic needles." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26584.
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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Colton, Jonathan; Committee Member: Ku, David; Committee Member: Prausnitz, Mark. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Sousa, Francisco Yuri Maia de. "CaracterizaÃÃo bioquÃmica e molecular da oxidase terminal da plastoquinona (PTOX) em Zea mays." Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7948.
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nÃo hÃO cloroplasto à uma organela caracterÃstica dos organismos fotossintetizantes sendo seu papel primordial na geraÃÃo de energia a partir de gÃs carbÃnico e Ãgua. Essa organela pode ter seu funcionamento comprometido quando submetida a estresses ambientais devido a fragilidade e complexidade do sistema. Para evitar perdas provocadas pelo estresse existem vÃrios mecanismos de adaptaÃÃo e regulaÃÃo das reaÃÃes que ocorrem no cloroplasto. Recentemente caracterizou-se mais um desses provÃveis mecanismos que foi chamado de clororespiraÃÃo. A clororespiraÃÃo foi esclarecida com a descoberta de uma enzima similar a oxidase alternativa da mitocondria que chamou-se de oxidase terminal do plastÃdeo (PTOX). A funÃÃo dessa respiraÃÃo do cloroplasto permanece incerta, mas uma das hipÃteses mais aceitas à que o funcionamento da clororespiraÃÃo poderia prevenir a formaÃÃo de espÃcies reativas de oxigÃnio atravÃs da reciclagem dos intermediÃrios redutores do cloroplasto. No presente trabalho foi caracterizado a presenÃa de dois genes que codificam para a oxidase terminal do plastÃdeo em plantas de Zea mays. Estudou-se tambÃm a expressÃo diferencial de ambos genes da PTOX em resposta ou estresse hÃdrico, alÃm da caracterizaÃÃo da clororespiraÃÃo atravÃs da atividade da NADH desidrogenase plastidial (NDH) em gel de poliacrilamida. A caracterizaÃÃo molecular dos genes da PTOX mostrou homologia de 60% quando comparadas as sequÃncias dos genes e de 79% quando comparadas as prÃ-proteÃnas traduzidas. Os genes dessa proteÃna tÃm estruturas similares, sendo compostos por oito introns e 9 Ãxons. Um estudo das regiÃes dos promotores dos genes mostrou que existiam elementos comuns porÃm a presenÃa de elementos diferentes como, o elementos cis MBS que à responssivo à seca, poderia revelar uma regulaÃÃo diferencial dos genes. A resposta diferencial foi confirmada atravÃs de RT-PCR semiquantitativo. O gene chamado de ptox1 teve sua expressÃo estÃvel, podendo ser considerado um gene constitutivo, enquanto que o gene chamado de ptox2 teve um aumento da expressÃo proporcional ao estresse aplicado tanto em folhas como em raÃzes de plantas de milho. A anÃlise da atividade da NDH em gel (zimograma) revelou a presenÃa dessa enzima em cloroplastos de milho confirmando a presenÃa das enzimas da clororespiraÃÃo. O estudo filogenÃtico de sequencias de cDNA de bancos de dados mostraram que milho e sorgo pertencentes ao grupo das monocotiledÃneas, sÃo espÃcies muito prÃximas e que compartilham dois genes ortÃlogos da PTOX identificados como ptox1 e ptox2. Concluiu-se pela primeira vez a presenÃa de dois genes da PTOX no genoma do milho, uma monocotiledÃena de metabolismo C4. Os genes foram denominados de ptox1 e ptox2. Eles foram encontrados em raÃzes e folhas e apenas o gene da ptox2 pareceu ser induzido em resposta ao estresse osmÃtico.
The chloroplast is an organelle characteristic of photosynthetic organisms and their role in generating energy from carbon dioxide and water. This organelle may be functionally compromised when subjected to environmental stresses due to the fragility and complexity of the system. To avoid losses caused by stress there are several mechanisms of adaptation and adjustment of the reactions that occur in the chloroplast. Recently characterized most likely of these mechanisms has been called clororespiraÃÃo. The clororespiraÃÃo was clarified with the discovery of an enzyme similar to mitochondria that the alternative oxidase is called terminal plastid oxidase (PtOx). The function of chloroplast respiration remains uncertain, but one of the most accepted hypothesis is that the operation of clororespiraÃÃo could prevent the formation of reactive oxygen species by recycling intermediate reducing the chloroplast. Characterized in this study was the presence of two genes coding for the terminal oxidase in plant plastid of Zea mays. Was also studied the differential expression of both genes in response PtOx or water stress, and the characterization of clororespiraÃÃo through the activity of the NADH dehydrogenase plastid (NDH) polyacrylamide gel. The molecular characterization of genes PtOx showed homology of 60% when comparing the sequences of genes and 79% when compared to the pre-translated proteins. Genes of this protein have similar structures are composed of eight introns and exons 9. A study of regions of the promoters of the genes showed that there were common elements but the presence of different elements as the cis elements that MBS is responssivo drought, could reveal a differential regulation of genes. The differential response was confirmed by semiquantitative RT-PCR. The gene was called ptox1 stable expression could be considered a constitutive gene, whereas the gene was called ptox2 increased expression proportional to applied stress in both leaves and roots of corn plants. The analysis of the activity of NDH gel (zymogram) revealed the presence of this enzyme in chloroplasts corn confirming the presence of enzymes clororespiraÃÃo. The phylogenetic analysis of cDNA sequences from databases showed that corn and sorghum in the group of monocots are closely related species which share two of the orthologous genes identified as PtOx ptox1 and ptox2. It appeared that the first time the presence of two genes PtOx into the maize genome, a C4 monocotiledÃena metabolism. Genes were named ptox1 and ptox2. They were found in the roots and leaves and only ptox2 gene appeared to be induced in response to osmotic stress.
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Rodriguez, Novoa Esteban Alejandro. "Expansion of the Swedish Deposit Return System for plastic packaging : Challenges and enablers along the value chain of plastics." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-288406.
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Plastic materials are widely used in different applications by the industry. Given its different properties, there is a wide range of utilization opportunities. From an environmental perspective, some of these properties imply a challenge for the recycling of these materials. Over the years, Deposit Return Systems (DRS) have been formulated and developed aiming to increase recycling rates of these materials. This study aims to determine if the expansion of the DRS for plastic materials can tackle current technical and logistical challenges that hinder the recyclability of these materials in Sweden. Specifically, it maps the actors and processes involved in the plastic value chain, identifying current challenges that affect the recyclability of the materials but also opportunities to increase the rates of recycling. Finally, after studying and characterizing different DRS implemented around the world, recommendations are given on what types of DRS expansions could be suitable for the Swedish context. Based on a literature review the current Swedish plastic value chain is studied and technical and logistical challenges are identified along it. Simultaneously the study investigates technological developments and innovations intended to improve the recyclability of the plastic materials. One of the main challenges identified is the fragmentation along the value chain, which is a barrier to utilizing the system to its full potential in terms of generating recyclable material as well as establishing well-functioning value regeneration of the materials. This information is useful to discussions on a future expansion of the DRS in Sweden. Likewise, after describing the different DRS options studied, recommendations are given for its implementation. The analysis concludes that given the current context that includes the start-up of a large sorting facility, the most promising option would be to opt for a design & sorting incentivizing DRS that is relying on the conventional waste management and does not require major investments in infrastructure. Other options are not discarded, but it is recognized that these may be more costly or more technologically demanding, also requiring more research to give an assertive assessment.Plastmaterial används ofta i olika applikationer av industrin med tanke på dess olika egenskaper. Miljömässigt innebär några av dessa egenskaper en utmaning för återvinning av dessa material. Under åren har pantsystem (Deposit Return Systems (DRS)) formulerats och utvecklats för att öka återvinningsgraden för dessa material. Denna studie syftar till att avgöra om expansionen av DRS för plastmaterial kan hantera nuvarande tekniska och logistiska utmaningar som hindrar återvinningsbarheten av dessa material i Sverige. Specifikt kartlägger uppsatsen de aktörer som är involverade i plastvärdekedjan och identifierar nuvarande utmaningar som påverkar materialens återvinningsbarhet, men också möjligheter att öka återvinningsgraden och slutligen efter att ha studerat olika DRS implementerade runt om i världen ges rekommendationer om huruvida vissa av dem är lämpliga för det svenska sammanhanget. Baserat på en litteraturstudie studeras den nuvarande svenska plastvärdekedjan och tekniska och logistiska utmaningar identifieras längs den. Samtidigt undersöker studien teknisk utveckling och innovationer som syftar till att förbättra återvinningsbarheten hos plastmaterialen. En av de viktigaste utmaningarna som identifierats är fragmenteringen och underutvecklingen längs värdekedjan, särskilt återvinningssektorn. Denna information är användbar för att fastställa trender i branschen men är också viktig att tänka på i formuleringen av en expansion av DRS i Sverige. På samma sätt, efter att ha beskrivit de olika DRS-alternativen, ges rekommendationer för dess genomförande. En slutsats är att med tanke på det nuvarande sammanhanget som inkluderar start av en stor sorteringsanläggning är det mer genomförbart att välja en modell för DRS som integreras i nuvarande kommunala avfallshantering och inte kräver större investeringar i infrastruktur. Systemet ska bygga på att skapa incitament för återvinningsbar design såväl som för ytterligare sortering. Andra alternativ avfärdas inte, men dessa kan vara mer kostsamma eller mer tekniskt utmanande och kräver mer forskning.
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Butterfield, Craig. "A novel laboratory dispersive and distributive minimixer and applications : development of a new minimixer that can duplicate mixing which occurs in a large twin screw extruder." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/4930.
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The mixing of additives into a plastic is an extremely important step in the plastics industry, necessary for the manufacture of almost every conceivable product. Therefore the costs in developing new products can prove very expensive as the testing is usually carried out using full scale machines, usually using twin screw extruders because they are able to provide good dispersive and distributive mixing. This is particularly important when compounding difficult to disperse additives and nano-additives. What is required is a machine that can replicate the mixing abilities of a twin-screw extruder but on a laboratory scale. There have been attempts by industry to develop smaller machines, such as the Thermo Scientific HAAKE Minilab II Micro Compounder which processes on the scale of 7 cm3 of material volume. This can be too small for some needs and therefore a machine is required to produce material on the 10g to 100g scale. To this end a laboratory mixer of novel design was devised and its mixing performance was assessed using conductive carbon black and compared against the Thermo Scientific HAAKE Minilab II Micro Compounder, a 19 mm co-rotating twin-screw extruder and a 40 mm co-rotating twin-screw extruder. Carbon black was used because mixing performance can be assessed by measuring the minimum carbon loading necessary to induce electrical conductivity. It was found that the minimixer was able to induce electrical conductivity at loading of 5.75% but the comparison with the other machines proved difficult as the achievement of the threshold at which semi-conductivity occurred appeared independent of shear rate and mixing duration.
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Adhikary, Kamal Babu. "Development of Wood Flour-Recycled Polymer Composite Panels As Building Materials." Thesis, University of Canterbury. Chemical and Process Engineering, 2008. http://hdl.handle.net/10092/1795.
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Wood plastic composites (WPCs) were made using matrices of recycled high-density polyethylene (rHDPE) and polypropylene (rPP) with sawdust (Pinus radiata) as filler. Corresponding WPCs were also made using virgin plastics (HDPE and PP) for comparison with the recycled plastic based composites. WPCs were made through melt compounding and hot-press moulding with varying formulations based on the plastic type (HDPE and PP), plastic form (recycled and virgin), wood flour content and addition of coupling agent. The dimensional stability and mechanical properties of WPCs were investigated. Durability performances of these WPCs were studied separately, by exposing to accelerated freeze-thaw (FT) cycles and ultraviolet (UV) radiation. The property degradation and colour changes of the weathered composites were also examined. Dimensional stability and flexural properties of WPCs were further investigated by incorporation of nanoclays in the composite formulation. To understand the changes in WPCs stability and durability performance, microstructure and thermal properties of the composites were examined. Two mathematical models were developed in this work, one model to simulate the moisture movement through the composites in long-term water immersion and the other model to predict the temperature profile in the composites during hot-press moulding.
Both rHDPE and rPP matrix based composites exhibited excellent dimensional stability and mechanical properties, which were comparable to those made from virgin plastics. Incorporation of maleated polypropylene (MAPP) coupling agent in composite formulation improved the stability and the mechanical properties. The incorporation of 3 wt. % MAPP coupling agent to WPCs showed an increase in tensile strength by 60% and 35 %, respectively, for the rHDPE based and rPP based composites with 50 wt. % wood flour. Scanning electron microscopy (SEM) images of the fractured surfaces of WPCs confirmed that the MAPP coupling improved the interfacial bonding between the plastic and the wood filler for both series of composites. Long-term water immersion tests showed that the water transport mechanism within the WPCs follows the kinetics of Fickian diffusion.
Dimensional stability and flexural properties of the WPC were degraded after 12 accelerated FT cycles as well as 2000 h of UV weathering for both recycled and virgin HDPE and PP based composites. However, the MAPP coupled composites had improved stability and flexural property degradation. The surface of the weathered composites experienced a colour change, which increased with the exposure time. The MAPP coupled composites exhibited less colour change as compared to non-coupled composites. Regarding the effect of the plastic type, the PP based composites experienced higher colour change than those based on HDPE. With weathering exposure, flexural strength and stiffness of the WPCs were decreased, but elongation at break was increased regardless of plastic type and wood flour content. MAPP coupled rPP and rHDPE based UV weathered WPCs lowered the degradation of stiffness by 50% and 75%, respectively compared to non-coupled WPCs. SEM images of the fractured surfaces of FT and UV weathered WPCs confirmed a decrease in the interfacial bonding between the wood flour and matrix. Thermal properties of weathered composites changed with weathering, but the extent of the changes depended on WPCs formulation and matrix type.
From the experimental studies on nanoclay-filled rHDPE composites, it is found that stability, flexural properties of WPCs could be improved with an appropriate combination of coupling agent, and nanoclay contents processed by melt blending. Incorporation of 1-5 wt. % nanoclay in the maleated polyethylene (MAPE) coupled wood plastic composite improved the dimensional stability and flexural properties. The thermal properties changed with the addition of nanoclay and MAPE in WPCs. In this work, a hot press-moulding model was proposed based on the one-dimensional transient heat conduction to predict the temperature profile of the WPCs during hot pressing cycle. The results from this work clearly show that rHDPE and rPP can be successfully used to produce stable and strong WPCs, which properties and performances are similar to or comparable to composites made of wood and virgin plastics. Therefore, WPCs based on recycled PP and HDPE matrix could have potential to use as construction materials.
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Monsigny, Louis. "Catalyseurs d’hydrosilylation pour la réduction de liaisons C-O dans les polymères oxygénés." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS026/document.
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L’objectif principal de cette thèse a été de développer de nouveaux systèmes catalytiques efficaces pour la dépolymérisation de la biomasse et des plastiques. La stratégie choisie pour favoriser cette transformation a été l’hydrosilylation de liaisons C-O. Le catalyseur d’iridium(III) de Brookhart s'est révélé particulièrement efficace pour l’hydrosilylation la lignine conduisant à des produits aromatiques purs avec des rendements très élevés. Il a également été utilisé pour la dépolymérisation réductrice de plastiques oxygénés qui ont permis d’isoler les monomères et des composés de haute valeur ajoutée.Dans un second temps, une dépolymérisation plus « verte » de polycarbonates et de polyesters a été mise en œuvre. Celle-ci ne fait intervenir ni métaux ni solvant grâce à l’utilisation du fluorure de tetra-n-butyle amonium comme catalyseur. Enfin, l’uranium appauvri, considéré comme un déchet de l’industrie nucléaire, a été valorisé comme catalyseur pour la réduction des liaisons C-O. Il a été découvert qu’un complexe de triflate d'uranyle favorisait efficacement le couplage réducteur de l'aldéhyde en présence d'hydrosilanes conduisant à l'éther symétriqueThe main objective of this thesis is the development of new efficient catalytic systems for the depolymerization of biomass and plastics. The chosen strategy to promote such transformations was the hydrosilylation of C-O bonds. Brookhart's iridium(III) catalyst was found to be very effective for hydrosilylation of lignin leading to pure aromatic products isolated in very high yields. It was also used for the reductive depolymerization of oxygenated plastics, allowing the isolation of monomers and valuable chemicals.In a second step, a "greener" depolymerization of polycarbonates and polyesters was implemented. This does not involve metals or solvents through the use of tetra-n-butyl amonium fluoride as a catalyst for hydrosilylation. Finally, depleted uranium, considered as a waste product of the nuclear industry, was valorized as a catalyst for the reduction of C-O bonds. It has been discovered that a uranyl(VI) triflate complex efficiently promotes reductive coupling of the aldehyde in the presence of hydrosilanes leading to symmetric ethers
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MacLean, Daniel. "Plastid transcriptomics and transcription of nuclear genes for the plastid genetic system." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.614945.
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Abdelkader, Amal Fadl. "Salt stress in wheat (Triticum aestivum) and its impact on plastid development /." Göteborg : Göteborg University, 2007. http://www.loc.gov/catdir/toc/fy0714/2007423862.html.
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Mallmann, Camila. "Mechanisms of plastic deformation of magnesium matrix nanocomposites." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAI083/document.
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Le magnésium est le plus léger des métaux, ce qui lui confère un fort potentiel pour être utilisé dans des applications où l’allégement des structures est requis. Pour autant, sa résistance mécanique est très faible, et doit donc être augmentée afin de rivaliser avec d’autres métaux légers tels que l’aluminium ou le titane. Une solution consiste à renforcer le magnésium et ses alliages en introduisant des nanoparticules d’oxydes. De par sa structure cristalline hexagonale compacte, le magnésium présente des propriétés plastiques complexes telles qu’une très forte anisotropie plastique et une prédisposition au maclage. La compréhension de ces mécanismes de déformation est essentielle pour le développement de nanocomposites plus performants en vue d’une utilisation industrielle plus répandue. Dans ce travail, nous nous sommes intéressés à l'élaboration et à la caractérisation de nanocomposites de magnésium pur renforcés par des particules d’oxydes. Différentes techniques ont été testées pour l’élaboration des nanocomposites : la solidification assistée aux ultrasons et le procédé de friction malaxage. L’homogénéité de la dispersion des particules a été vérifiée en 2D par observations en microscopie électronique et également en 3D par tomographie aux rayons X. On montre ainsi que le procédé de friction malaxage permet d'obtenir une distribution homogène des particules, tout en réduisant leur taille. Des essais de traction ont permis de mettre en évidence une augmentation de la limité d’élasticité pour une fraction volumique aussi faible que 0.3 %. Afin d’isoler le rôle des particules de celui des joints de grains sur le comportement plastique du nanocomposite, nous avons réalisé des essais de micro-compression sur des micro-piliers monocristallins usinés par canon à ions focalisés (FIB) dans des échantillons ayant préalablement subis un traitement thermique favorisant la croissance anormale des grains. Différentes orientations cristallines et tailles de micro-piliers ont été testées en vue d'étudier l’influence des particules d’une part sur la plasticité dans le plan basal par mouvement de dislocations et d’autre part sur la déformation par maclage. Contre toute attente, les essais sur monocristaux favorablement orientés pour un glissement basal ne montrent pas l’effet durcissant observé macroscopiquement. Nous attribuons cet effet à la densité initiale de dislocations mobiles, plus importante dans les nanocomposites que dans le magnésium pur, du fait des concentrations de contraintes autour des particules. Ces densités initiales de dislocations mobiles tendent également à supprimer l'effet de taille classiquement observé dans le magnésium pur. Les particules modifient également le mécanisme de déformation par maclage en favorisant l’apparition simultanée de plusieurs macles dans le micro-pilier qui interagissent entre elles au cours de la déformation alors que les micro-piliers de magnésium pur présentent généralement une macle unique (dans certains cas deux) qui envahi tout le monocristal. Ces résultats constituent une contribution originale à la compréhension du rôle des nanoparticules dans la déformation plastique des monocristaux de nanocomposites à base de magnésiumMagnesium is the lightest of all structural metals, which gives it a huge potential to be used in applications that require lightweighting. However, its strength needs to be increased in order to compete with other light metals such as aluminum and titanium. A solution is the reinforcement of magnesium and its alloys with the addition of oxide nanoparticles. The hexagonal close packed crystalline structure is responsible for the complex plasticity of magnesium, which is characterized by a very strong plastic anisotropy as well as a complex twinning activity. Understanding these deformation mechanisms is crucial for the development of more performant nanocomposites, allowing widespread industrial application. The present work focuses on the processing and characterization of magnesium based nanocomposites reinforced with oxide particles. Two different processing techniques have been compared: friction stir processing and ultrasound assisted casting. The homogeneity of the dispersion of the reinforcement particles has been verified in 2 and 3 dimensions using electron microscopy and X-ray tomography, respectively. Friction stir processing produces nanocomposites with a more homogeneous dispersion of particles, while reducing their size. Tensile tests have shown strengthening of magnesium with the addition of a volume fraction of only 0.3 % of reinforcement. An annealing heat treatment has then been performed in order to promote abnormal grain growth and single crystalline microcolumns for microcompression testing have been machined by focused ion beam (FIB). The purpose is to isolate the role of particles. The orientation dependent mechanism of deformation and the size effects have been studied in order to understand the influence of the reinforcement particles on the plasticity for orientations favorable for basal slip or tensile twinning. Differently from the strengthening observed macroscopically, no clear strengthening effect is observed on microcolumns when dislocation glide operates. The reason is the higher density of potentially mobile dislocations that is generated due to stress concentrations around the reinforcement particles. In addition, the size effects usually observed on pure magnesium have also been suppressed with the addition of particles. The reinforcement particles seem to affect the twin nucleation stress and twin morphology: particles induce the nucleation of multiple twins inside a microcolumn, whereas in pure magnesium, only one or two twins have been observed. These results provide relevant insights on the role of nanoparticles on the onset of plastic deformation, as well as size effect, in single crystalline magnesium nanocomposites
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Ackerstierna, Paula. "The Environmental Impact of an Automotive Plastic Component : A lifecycle approach of a deco panel scenario analysis of two different plastics." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-73177.
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The transport sector is a major end-user of energy. As consumers are becoming aware and conscious of their environmental footprint making the enviromental footprint of automobile components one of the requirements in new product design development. The purpose of the study is to identify environmental impacts of a plastic panel. The main objective of the study is to perform an environmental life cycle assessment (E-LCA) of an existing panel regarding four scenarios with a nonbio-based plastic and a bio-based plastic. The first two scenarios have the same production and use phase, but different end-of-life treatments. The plastic in these scenarios is non-biobased. The last two scenarios have the same bio-based plastic and use phase, but different end-of-life-treatments. The first three scenarios have a surface material covering the plastic. The environmental impacts analyzed are global warming potential, acidification potential, eutrophication potential, photochemical ozone creation potential, primary energy demand and particulate matter. The analysis is carried out according to the ISO14040/44 with the four steps of LCA: 1) Goal and Scope Definition, 2) Inventory Analysis, 3) Impact Assessment, and 4) Interpretation. The functional unit of the anaysis is a plastic panel. The inventory was collected by literature, the LCA software GaBi, and the commissoner of the study. The environmental impact assessment was conducted in GaBi 8 with the method of CML2015, Primary Energy, and IMPACT2002+. A dominance and a contribution analyses were applied to identify the hotspots of the life cycle. The hotspot of the life cycle was identified to be the production phase. The main contributor within the scenarios was the plastic production, specifically the granulates and the fiber fillings. The bio-based plastic reduced the impacts compared to the non-bio-based in five out of six cases. However, the photochemical ozone creation potential for both plastics were the same. The bio-based plastic reduced the GWP 16%, AP by 1%, EP by less than 1%, and PED by 19%. If the surface cover in aluminum was removed, the GWP was reduced by 46%, AP by 35%, EP by29%, POCP by 36%, PED by 42%and PM by 40%. The transportation contributed most to impacts in the acidification potential, eutrophication potential, and particulate matter. The transportation’s impacts were greater in the bio-based plastic than the non-bio-based. The granulates of the plastic along with the injection molding are the main contributors due to usage of coal-based electricity for the injection molding and oil for the plastic production. The values used in the study are based on country averages which may differ depending on geographic location and its development as China is a country with a large area. The GWP is the highest value of the impacts analyzed, but even though the other are small fractions these may cause great damages. These damages can irritate eyes, damage lungs and destroy photosynthesis. By using recycled material for products instead of new materials, as done in the study, the impacts could be lower. As some previous studies agrees, the usage of bio-plastics lowers the environmental impact by a few percentages. The bioplastic is an environmentally sustainable option to the current plastic as the location of the panel is not sensitive to excessive heat.
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Zhelyazkova, Petya. "The transcriptome of barley chloroplasts revealed by deep sequencing." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2013. http://dx.doi.org/10.18452/16649.
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Die gegenwärtige Vorstellung von Genexpression in Plastiden leitet sich von der Analyse weniger, individueller Gene ab und ist deshalb noch relativ lückenhaft. In dieser Arbeit sollte daher differenzierende RNA Sequenzierung- eine neue Methode, die zwischen prozessierten und Primärtranskripten unterscheiden kann, verwendet werden, um ein vollständigeres Bild des Transkriptionsprozesses und der RNA Prozessierung von Hordeum vulgare L. (Gerste) Chloroplasten zu erhalten. Plastidengene in höheren Pflanzen können sowohl von einer plastidenkodierten, bakterienähnlichen RNA-Polymerase (PEP), als auch von einer kernkodierten, phagenähnlichen RNA-Polymerase (NEP), die beide unterschiedliche Promotoren erkennen, abgelesen werden. In dieser Arbeit wurde die Verteilung von Transkriptionsstartstellen innerhalb des Plastidengenoms von grünen (reife Chloroplasten; Transkriptionsaktivität von PEP und NEP) und weißen Plastiden (Transkriptionsaktivität von NEP) der Gerstenmutantenlinie albostrians analysiert. Dies führte zu neuen Erkenntnissen bezüglich polymerasenspezifischer Genexpression in Plastiden. Auf Grundlage neuerer Arbeiten wird angenommen, daß nicht kodierende RNAs (ncRNAs) in Chloroplasten vorkommen. Die bisher verwendeten Methoden waren jedoch nicht geeignet, ncRNAs als Primärtranskripte zu identifizieren, die zumindest in Prokaryoten die häufigste Klasse von ncRNAs darstellen. In dieser Arbeit konnte durch dRNA-seq gezeigt werden, daß auch in Plastiden zahlreiche ncRNAs als Primärtranskripte generiert werden. Die wichtigsten Schritte im Prozess der mRNA Reifung in Plastiden sind 5´und 3´ Endformation und intercistronische Prozessierung. Vor Kurzem wurde gezeigt, daß ein PPR (Pentatricopeptide repeat) Protein zur Bildung der Ende von einigen prozessierten Plastiden mRNAs beiträgt, indem es als Hindernis für Exonukleasen wirkt. Mit dieser Arbeit konnte gezeigt werden, daß dies ein genereller Mechanismus zur Bildung prozessierter mRNA-Enden in Chloroplasten ist.The current view on plastid gene expression is mainly based on the analysis of a few individual genes, and thus it is lacking in comprehensiveness. Here, a novel differential RNA-seq approach, designed to discriminate between primary and processed transcripts, was used to obtain a deeper insight into the plastid transcription and RNA maturation of mature barley (Hordeum vulgare L.) chloroplasts. Transcription in plastids of higher plants is dependent on two different transcription machineries, a plastid-encoded bacterial-type RNA polymerase (PEP) and a nuclear-encoded phage-type RNA polymerase (NEP), which recognize distinct types of promoters. This study provided a thorough investigation into the distribution of transcription start sites within the plastid genome of green (mature chloroplasts; transcription by both PEP and NEP) and white (PEP-deficient plastids; transcription by NEP) plastids of the barley line albostrians. This analysis led to new insights on polymerase specific gene expression in plastids. Recent studies have suggested that non-coding RNAs (ncRNAs) are common in chloroplasts. However, they did not directly detect ncRNAs generated via transcription, the so far most abundant class of known regulatory ncRNAs in bacteria. Here, dRNA-seq analysis of the transcriptome of barley chloroplasts demonstrated the existence of numerous ncRNA generated via transcription of free-standing genes. Major events in plastid mRNA maturation include 5’ and 3’ processed end formation and intercistronic processing. Recently, a PPR (pentatricopeptide repeat) protein was shown to participate in the generation of several plastid mRNA processed ends by serving as a barrier to exonucleases. This study provided evidence for the global impact of this mechanism on processed termini formation in chloroplasts.
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Herlin, Christian. "Modélisation et stimulation du comportement du complexe peau / tissu sous-cutané en chirurgie plastique d'augmentation tissulaire." Thesis, Montpellier 1, 2014. http://www.theses.fr/2014MON1T025/document.
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Contexte: Simuler le comportement du complexe peau/tissu sous-cutané (CPTSC) au cours d'une chirurgie présente de nombreuses difficultés liées principalement à sa complexité anatomique qui génère un comportement mécanique complexe. Les modèles de simulation existants sur ce sujet se présentent majoritairement sous forme d'une mono-couche homogène et isotrope de comportement élastique linéaire. Ils ne prennent jamais en considération les moyens d'union conjonctifs du CPTSC pourtant responsables de la complexité de son comportement mécanique. L'augmentation tissulaire chirurgicale et en particulier l'autogreffe adipocytaire vise à restituer un volume corporel amputé par exemple par un traumatisme ou par une chirurgie carcinologique. A l'heure actuelle, seule l'expérience du chirurgien permet de prévoir l'effet d'une chirurgie d'augmentation tissulaire dans un contexte préopératoire donné. Un outil de simulation et de prévision fiable permettrait d'améliorer l'adhésion des patients à certains protocoles de traitement lourds, d'éviter certaines impasses thérapeutiques ou pourrait servir de support pédagogique.Objectifs: Dans un but de simulation et de prévision chirurgicale, nous avons souhaité développer un modèle mécanique du complexe peau tissu sous-cutané entièrement paramétrable par certaines données morphologiques des patients et adaptable à toute les régions du corps.Patients et méthodes: Afin de confirmer l'existence d'un modèle organisationnel générique du CPTSC, nous avons fait plusieurs acquisitions en IRM 3T de l'ensemble du corps. Ces acquisitions nous ont permis de mettre en évidence une organisation générique du CPTSC qui à été la base d'un modèle géométrique générique paramétrable. Afin de reconstituer l'architecture lobulaire du tissu adipeux et afin de restituer l'effet mécanique des moyens d'unions conjonctifs du CPTSC, nous avons construit de manière procédurale, à l'aide d'une tesselation de Voronoï, l'anatomie lobulaire et les septas inter-lobulaires. Une modélisation mécanique hybride a été réalisée grâce à la plateforme SOFA afin de respecter fidèlement l'organisation complexe du tissu de soutient collagénique. Pour valider le comportement mécanique de notre modèle, nous avons transcrit puis comparer les paramètres de tests d'indentation in vivo à notre modèle générique. Concernant l'augmentation tissulaire, nous avons simulé le phénomène de peau d'orange et les effets de l'autogreffe adipocytaire au dessus et en dessous du plan de fascia superficialis. Nous avons ensuite étudié les conséquences biomécaniques des fasciotomies qui sont utilisées en pratique courante. Nous avons finalement inclus ce modèle générique dans un modèle de face généré à partir des acquisitions IRM afin de simuler une autogreffe adipocytaire au niveau de la face. Résultats: Le modèle générique, paramétré de manière spécifique, nous a permis de transcrire de manière réaliste les tests d'indentation au niveau de l'avant-bras. Les simulations d'injection de graisse autologue ont pu simuler fidèlement les constatations opératoires et nous avons par ailleurs été capable de simuler le phénomène de peau d'orange en s'appuyant sur certaines de ses hypothèses physiopathologique. La simulation des fasciotomies nous a permis d'étudier pour la première fois l'effet mécanique de cette procédure. L'inclusion du modèle procédural dans un modèle géométrique spécifique de la face, acquis à partir de nos images IRM 3T, a pu aboutir à une simulation d'une autogreffe adipocytaire dans la joue. Conclusion: Malgré la mécanique complexe des tissus mous, nous avons pu établir un modèle mécanique fiable qui peut être spécifié de manière paramétrique. Après une phase de validation clinique et certaines améliorations mécaniques, nous souhaitons mettre au point des modèles spécifiques utilisables en simulation chirurgicaleBackground: Simulate the skin / subcutaneous tissue complex behavior presents many difficulties mainly related to its anatomical complexity that generates a complex mechanical behavior. Current simulation models on this subject appear mainly in the form of a homogeneous single layer of isotropic and linear elastic behavior. They never take into account the connective means of union of the skin and subcutaneous tissue which are responsible of the complexity of the mechanical behavior. The surgical tissue augmentation procedures and in particular autologous fat grafting aims to restore corporal volumes after a trauma or a carcinologic surgery. Currently, only the experience of the surgeon can predict the effect of a surgical tissue augmentation in a given preoperative context. A simulation and reliable prediction tool would improve patient adherence to certain protocols of heavy treatment, would avoid certain therapeutic impasses or could be used as a teaching aid.Objectives: As a surgical prevision and simulation tool, we wanted to develop a mechanical model of the skin / subcutaneous complex fully configurable by certain morphological data of patients and adaptable to any parts of the body. Patients and methods: To confirm the existence of a generic organizational model of subcutaneous tissue, we made several acquisitions in 3T MRI of the whole body. These acquisitions allowed us to highlight a generic pattern of organization of subcutaneous tissue that has been the basis of a generic geometric model fully configurable. To reconstruct the lobular architecture of adipose tissue and to restore the mechanical effect of the connective means of union, we constructed in a procedural manner, using a Voronoi tessellation. Hybrid mechanical modeling was performed with the SOFA framework. To validate the mechanical behavior of our model, we parametrized our generic model and transcribed the parameters of an in vivo indentation test and compare the results. Concerning tissue augmentation procedures, we simulated the phenomenon of cellulite and the effects of autologous fat grafting above and below the plane of superficial fascia. We then studied the biomechanical consequences of fasciotomies which are used in current practice. We finally included in our generic model of a face model generated from MRI acquisitions to simulate autologous adipocyte at the level of the cheek. Results: The model, allowed us to transcribe realistically indentation tests at the level of the forearm. Autologous fat injection simulations have faithfully simulate the operative findings and we have also been able to simulate the phenomenon of cellulite relying on some of its pathophysiological hypotheses. The simulation of fasciotomies has allowed us to study for the first time, the mechanical effect of this procedure. The inclusion of procedural model in a specific geometric model of the face result in an acurate simulation cheek fat grafting. Conclusion: Despite the complex mechanics of non visceral soft tissues, we have established a reliable mechanical model that can be specified parametrically. After a phase of clinical validation and some mechanical improvements, we hope to develop specific models used in surgical simulation
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Štrimaitis, Mantas. "Liejimo slegiant formų projektavimo, gamybos technologinio paruošimo ir gamybos problemų analizė ir sprendimai." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090623_110855-78181.
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Baigiamajame magistro darbe nagrinėjamos liejimo slegiant formų projektavimo, ga-mybos technologinio paruošimo bei gamybos proceso problemos ir aptariami novatoriški jų sprendimo būdai. Apžvelgiami plastinių medžiagų perdirbimo procesai. Analizuojamas tradi-cinis liejimo slegiant formų gamybos procesas ir jo trūkumai. Pateikiami organizaciniai ir te-chniniai tradicinio gamybos proceso tobulinimo būdai, panaudojant naujausią programinę įrangą, įrankius, medžiagas ir stakles. Tiriamojoje dalyje atliekamas ruošinio parinkimo įtakos liejimo formos detalių savikainai modeliavimas. Išanalizavus visas liejimo slegiant formų ga-mybos problemas, pateikiamos baigiamojo darbo išvados ir siūlymai. Darbą sudaro 7 dalys: įvadas, plastikų perdirbimas, tradicinio liejimo slegiant formų gamybos proceso analizė, liejimo slegiant formų gamybos proceso šiuolaikinės tobulinimo kryptys, ruošinio parinkimo įtakos liejimo formos detalių savikainai modeliavimas, išvados ir pasiūlymai, literatūros sąrašas. Darbo apimtis – 73 p. teksto be priedų, 50 iliustr., 14 lent., 21 bibliografinis šaltinis. Atskirai pridedami darbo priedai.In this final master work are investigated plastic injection moulds design, production technological preparation and production problems and discussed innovative solution ways of these problems. Reviewed remake processes of plastic meterials. Analysed tradicional plastic injection mould production process and its weaknesses. Gived organizational and technical tra-dicional production process improvement ways handling the modern software, tools, materials and machines. In investigational part is performed modeling of billet selection influence to cost price of mould parts. After analysis of all the plastic injection moulds production problems gived conclusions and suggestions of this final work. Structure: introduction, remake of plastics, traditional plastic injection moulds production process analysis, modern improvement ways of plastic injection moulds production process, modeling of billet selection influence to cost price of mould parts, conclusions and suggestions, references. Thesis consist of: 73 p. text without appendixes, 50 pictures, 14 tables, 21 bibliographi-cal entries. Appendixes included.
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Davies, Gareth Benjamin Harverd. "Environmental packaging." Thesis, Brunel University, 2006. http://bura.brunel.ac.uk/handle/2438/5340.
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The food packaging industry is a £300bn global industry growing at a rate of 12% per year and increasingly favouring polymer or polymer-based materials. This generates 58m tonnes of "plastic" packaging waste annually in the EU and poses significant challenges for management given existing legislative constraints and increasing concerns surrounding the environmental impacts. The government, consumers, food retailers and pressure groups are all driving the demand for biodegradable packaging from renewable resources that can be disposed of with reduced impacts to the environment. Green Peace has devised a pyramid classification system of "Poisonous Plastics", which ranks plastics in terms of their harmfulness to the environment. They are campaigning against the use of oil-based materials and advocating the take up of biodegradable materials. The market for biodegradable food packaging is expanding rapidly but is still in its early stages of development and has not reached a critical mass to achieve significant market penetration. This is predominantly due to a lack of suitable materials that meet all environmental, functional and economical requirements. Whilst the long-term solution requires continued efforts in materials research and development, in the shorter term, changing working practices can abate the environmental impact of the industry. This research project tackled the challenge of environmental packaging from several directions: A novel starch-based material was developed that would fill the current gap in the food packaging market and facilitate recovery of the used materials by home composting. Using the sponsoring organisation as a case study, it was proved that by changing working practices by increasing rework and re-processing waste material for use in lower grade applications, both manufacturing costs and environmental impact can be reduced, thus benefiting both industry and the environment. A Life Cycle Assessment of selected biopolymers and oil-based polymers confirmed Green Peace's damning view of PVC and highlighted the need to develop biopolymers further. A domestic composting study of a range of commercially available "biodegradable" polymer materials revealed that a number of biodegradable packaging materials may typically biodegrade well in industrial high-temperature composting systems but fail to biodegrade under a low-temperature home composting environment and thus alerted the potential pitfall in waste management of some biodegradable polymers.
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No, Donghun. "A study of the combined socket and butt welding of plastic pipes using through transmission infrared welding." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1104437266.
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Porter, Laura E. "Royal Secrets in the Queen's Body Fat." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLET038/document.
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Le présent mémoire propose un accès à ce qui se joue dans le choix des matériaux que j’utilise dans mon travail artistique (matières plastiques, dessins industriels, graines, coupons…) ainsi que le rendement, symbolique ou sensoriel, associé à ces matériaux (nourriture, confort, ergonomie, sécurité, production de sensations, production de valeur…). Je m’intéresse également aux tentatives industrielles d’utilisation de ces matériaux en vue de satisfaire de manière concrète certaines créations conceptuelles issues du langage (« indoor/outdoor », « substance », « synthétique »…).Les différentes parties qui composent le mémoire soulignent le caractère glissant des systèmes de valeur dans lesquels s’inscrivent les objets, l'alimentation et l'argent. Il s’agit d’observer les tentatives, parfois paradoxales, d’adapter des produits ou des matériaux à certains modes de quantification et de mesure particuliers, et les failles résultant de ces tentatives : failles matérielles, non idéologiques, comme par exemple la production d’argent invalide ou de pain non reconnu comme tel.La première partie du mémoire, Domefood, réunit les modes de représentation du mangeable dans lesquels le corps se projette.The Food Amounts Booklet, un ensemble de dessins développés dans les années 1980 pour quantifier l’apport de nourriture à partir de souvenirs et de descriptions, est outil fait pour mesurer la quantité de graisse dans un corps, par la projection d’une quantité mémorisée (et donc en partie imaginaire) de nourriture consommée sur des formes bidimensionnelles, indépendamment de toute échelle concrète. Des produits industriels comme les cameras GoPro et les capsules ongles entraînent également le corps à se « projeter » hors de lui-même en permettant un regard inédit, depuis le point de vue de ses extrémités. Le concept d’indoor/outdoor désigne les produits qui tentent d’effacer la différence entre l’intérieur domestique de l’habitat et la nature extérieure (semelles intérieures, moquette, système d’aspiration centrale…). Dans le domaine du design d’interface, le skeuomorphisme vise, par une sorte de camouflage, à favoriser la projection de qualités normalement associées à certains objets (texture, apparence, bruits…) en adaptant la matière à une attente sensorielle spécifique. Il donne naissance à des produits paradoxaux comme les hosties sans gluten, qui font ressurgir des problèmes relatifs à la réduction de la matière à des noms et à des symboles (ici, pain et substance), au cœur du débat sur la transsubstantiation.La deuxième partie du mémoire, Lawn, regroupe quelques pistes sur l’acheminement des matériaux plastiques vers une économie du jetable, ainsi que le développement du concept « synthétique ». Créés à partir d’un réarrangement de la nature, les plastiques sont des matériaux dont le caractère jetable définit la trajectoire et les motifs. Mais bien que jetables, les plastiques sont aussi symboles de durabilité et de résistance : résistants en tant que matière, mais aussi dans toutes les transformations qu’ils peuvent subir, leur capacité à imiter toutes sortes de textures, de surfaces, de formes. En plus de lui offrir une matière adaptée au geste de la consommation, les plastiques modifient le corps, ils le complètent (prothèses, sacs, accessoires, etc.), mais ils rendent également possible sa dissémination inédite. Avec les plastiques, les parties corps deviennent parties de différents ensembles.La troisième partie du mémoire, Spenders, est une liste d’exemples mettant en avant l’argent tel qu’il est en train d’être dépensé, non plus dans sa dimension virtuelle (garante de l’effectivité des transactions), mais en tant que matière. La matière de l’argent, même quand elle est fabriquée spécialement pour faciliter les échanges, met en lumière les limites de son usage. Parce que l’argent est ce qui oriente le système économique, il doit nécessairement être incarné comme matièreList of works made during the doctorate SACRe:Insole, Slack, Pro’jet, Maquette pour Simon, Heureusement les tomates, H-dropper (2014)Float, Wampum, Doozer, Sourdough, Pervert’s Tailgate, Tips, Reel, DomeFood, Double-booty, No-Spenders, le Chouchou des nanas, Cimaise (2015)Future of Dry, Un espace vide ça n'a pas de sens, Poor Man Good Water, Tableau, Mounds, Spenders, Five Cents, Foam Home, Bust, Nickel Coin, Penny Perspective, Like Farming, Gainer (2016)Rook, Skip Cups, Still Life avec Jennifer, La Possibilité que je m'appelle moi-même, Étalon et son maître, Mö, Boo Berry, Peeler, Mick Swayze, Slunder, Woody Sketch, Judgment of Crop, Cookie Numbness, Healer (2017)
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Orme, Wendy. "A plastid DnaJ in Arabidopsis." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270855.
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