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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Generování výstupních sestav v prostředí webu / Generating printouts on the Web

Kolafa, Lukáš January 2010 (has links)
Today it is very often necessary to print different documents from company information systems. These documents, that are designed to represent the company, contain information that is usually stored in databases. The goal of this thesis is to show the methods for the automatic conversion of data into formatted documents. My aim is to show some methods, how to automatically generate printouts and how to create templates for them in an easy way. For the purpose of this thesis, I've developed a small web application, which stands for an information system of a logistics company. The application allows creating documents with the help of templates. All documents are generated in generally common formats.
62

Detection of latex aeroallergens in dental schools

Mabe, Dikeledi Onnicah 25 May 2009 (has links)
Introduction: Exposure to airborne natural rubber latex proteins has become an important occupational health concern, particularly among healthcare workers. The main purpose of this study was to investigate the levels of latex aeroallergens in South African dental schools. Methods: Area (n=95) and personal (n=369) samples as well as rubber containing gloves and dental devices (n=19) were collected in 5 dental schools. The air samples were collected at a flow rate of 2.5L/min using polycarbonate (PC) filters. Latex allergens (hev b 1, hev b 3, hev b 5 and hev b 6.02) were quantified in filters and rubber extracts by a capture enzyme immunoassay. Data was analysed using STATA 9 computer software (StataCorp, 1984-2007, Texas, USA). Non parametric tests were applied as the data was skewed. The data was interpreted as ‘low’ with less than 10ng/m3; ‘moderate’ with levels between 10-50ng/m3 and ‘high’ with greater than 50ng/m3. Results: Aeroallergen concentrations varied among institutions in our study, ranging from 1.84 to 46.1ng/m3 for personal and 1.33 to 14.97ng/m3 for area samples. Hev b 6.02 was below the detection limit for 86.5% of air samples. This study also found that exposure levels differed by departments and job type. Powdered latex products showed higher allergen concentrations compared to the non-powdered products (p=0.035) and also differed significantly by the type of brands (p=0.022). Hev b 6.02 was the most prominent allergen in powdered gloves and dams. Conclusion: The air sampling method and capture enzyme immunoassay used in this study offer means for evaluation of airborne allergen concentrations. The initiative to use non-powdered low protein latex gloves and dams should be implemented as a preventive measure.
63

Obtenção e propriedades de nanocompósitos borracha/argila a partir de látices de borrachas comerciais e borrachas epoxidadas

Azeredo, Luciane Klafke de January 2009 (has links)
Atualmente, nanocompósitos têm sido alvo de grande interesse científico e tecnológico. Além do negro-de-fumo e da sílica, materiais já consagrados como nanopartículas de reforço para uma grande variedade de borrachas, outras nanopartículas funcionalizadas têm sido o centro das atenções. Especialmente, nanopartículas bidimensionais (lâminas) e unidimensionais (tubos ou fibras, com destaque aos nanotubos de carbono) têm surgido como excelentes candidatos a partículas de reforço e apresentando efeito superior, já a frações volumétricas muito pequenas, bem inferiores às aplicadas tradicionalmente. Este trabalho tinha como objetivo investigar a epoxidação de polibutadieno e explorar a potencialidade de sílicas lamelares, especialmente filossilicatos 2:1, como agentes efetivos de reforço e barreira. Para alcançar este objetivo uma nova tecnologia de mistura e dispersão para a argila montmorilonita (MMT) foi desenvolvida. Baseia-se na Coagulação Dinâmica Contínua de Látex (“Continuous Dynamic Latex Coumpounding - CDLC"), na qual MMT é misturada ao látex de borracha e dispersa, adequadamente, em um regime especial de fluxo. O método vale-se do potencial que a água possui de enfraquecer os contatos interlamelares da MMT. Látices de NR, SBR, NBR e XNBR foram investigados. As condições de processo afetam a morfologia dos nanocompósitos, determinada por MET e DRX. A polaridade das borrachas influencia a dispersão da MMT e, consequentemente, as propriedades finais dos nanocompósitos. Comparando-se estes nanocompósitos com compósitos obtidos com negro-de-fumo, sílica precipitada ou mesmo com argila obtidos pelo processo da incorporação no estado fundido, os de CDLC exibem desempenho de reforço e uma resistência à permeação superiores, mesmo aplicando-se frações volumétricas de carga bem inferiores. Paralelamente, mostrou-se que é possível epoxidar polibutadieno comercial, a partir do meio reacional de polimerização, em ciclohexano, limitando-se em 30% em mol, face ao limite de solubilidade da borracha epoxidada no solvente. Nanocompósitos de polibutadieno epoxidado com argila foram preparados obtendose também propriedades melhores do que a borracha epoxidada pura. Com estes resultados, o presente trabalho mostra novas oportunidades para a obtenção de nanocompósitos elastoméricos. / Nowadays, polymer nanocomposites received an increasing scientific and technological interest. Besides carbon black and silica which have been proven reinforcing nanofillers for a large variety of rubber, other types of functional nanoparticles are coming in the center of this attention. Especially two-dimensional nanoparticles (platelets) and one-dimensional tubes or fibers (i.e. carbon nanotubes) are serious candidates to determine large reinforcing effects as for less volume fraction than traditional fillers. This work had as objective to investigate the epoxidation of polybutadiene and to explore the potential of layered silicas, especially 2:1 phylosilicates, as reinforcing agents and effective permeation barriers. In order to achieve this objective a new mixing and dispersion technology for montmorillonite (MMT) was developed in this work. This technology is based on “Continuous Dynamic Latex Compounding” (CDLC), in which MMT is mixed with a rubber latex and well dispersed in particular flow regime. Due to the coagulation of the latex, it was possible to prepare superior types of rubber nanocomposites. One important fact is that the interlayer contacts in the MMT tactoids are weakened by swelling in water. Latices of NR, SBR, NBR and XNBR have been used. It is shown that the process conditions affect the phase morphology of nanocomposites characterized by transmission electron microscopy and x-ray diffraction. The polarity of rubbers influence the dispersion of MMT as well as the properties of the resulting nanocomposites. Compared to nanocomposites filled with carbon black, precipitated silica, or those obtained by melt mixing, nanocomposites by CDLC demonstrate a better reinforcement and permeation resistance at far less volume fractions. The epoxidation of commercial polybutadiene with high cis content, from its commercial solution (cyclohexan), was possible, but due to the solubility of epoxidized polymer, the system coagulated and gelated when a epoxidation degree of 30 mol% was reached, independent of the initial concentrations of reagents. Nanocomposites from polybutadiene, 14 and 19 mol% epoxidation degree, and organoclay were prepared. The mechanical and barrier properties had been superior to those compositions of epoxidized polybutadiene without clay. By this achievements, the present work demonstrate new opportunities for polymeric nanocomposites.
64

Approaches to understanding diversity in rubber and carotenoid synthesis in Hevea brasiliensis latex

Bahari, Azlina January 2019 (has links)
<i>Hevea brasiliensis </i>latex contains a large quantity of high molecular weight rubber and is thus the primary commercial source of natural rubber. Rubber and other non-rubber isoprenoids in <i>Hevea </i>latex are synthesised from isopentenyl diphosphate (IPP) generated from the cytoplasmic mevalonate (MVA) pathway and the plastidic methyl erythritol phosphate pathway (MEP). This study utilised two rubber tree clones (RRIM600 and PB235) that show visibly contrasting levels of yellow carotenoids for the measurement of latex isoprenoids (carotenoids, rubber and isoprenoid intermediates) and transcript levels of the genes involved in isoprenoid biosynthesis. Metabolite extraction and analysis showed that four major carotenoids namely lutein, zeaxanthin, α-carotene and β-carotene were consistently present in both RRIM600 and PB235 latex. β-carotene was found to be the major carotenoid, at 1.2 μg/g in PB235 and 0.8 μg/g in RRIM600 fresh latex samples. However, the analytical method developed to measure isoprenoid intermediates needed to be further optimised to increase extraction efficiency. To enable accurate measurement of transcript levels of key genes involved in the isoprenoid biosynthetic pathway, a set of reference transcripts was constructed by merging short-reads (RNA-seq) and long-reads (Iso-seq and full-length cDNA sequences) data from <i>Hevea brasiliensis</i>. This produced a comprehensive set of 193,997 transcript sequences with good level of coverage of predicted transcripts and highly conserved core plant genes. Not only did the reference transcriptome update the annotation of rubber gene models, additional transcript variants were also discovered. Manual curation of gene models for key steps associated with rubber and carotenoids resulted in a repertoire of 115 genes, with 151 corresponding transcript variants. Subsequently, differential expression analysis on the basis of mapping RRIM600 and PB235 RNA-seq reads to the reference transcriptome revealed isoform-specific expression of genes for biosynthesis of carotenoids (PSY isoform 2), IPP (AACT2 and HMGR1) and rubber (REFSRPP gene members). In addition, the levels of these genes correlated positively with the carotenoid and rubber content measurements from the same latex of PB235 and RRIM600 used for metabolite extraction. Finally, the utility of the reference transcript catalogue was demonstrated by the characterisation of the REFSRPP gene family, which is involved in rubber elongation steps. REFSRPP gene family showed a local expansion which appear to be unique to <i>Hevea</i>. A pilot study has demonstrated there is considerable diversity of the genomic region containing the duplicated REFSRPP genes.
65

The human immune response to the latex allergen Hev b 5

Sutherland, Michael F. (Michael Fraser), 1967- January 2003 (has links)
Abstract not available
66

The human immune response to the latex allergen Hev b 5

Sutherland, Michael F. (Michael Fraser), 1967- January 2003 (has links)
For thesis abstract select View Thesis Title, Contents and Abstract
67

Vom TeX-Dokument zur Druckerei

Pönisch, Jens 13 November 2001 (has links) (PDF)
Erzeugen von Dokumenten aus TeX/LaTeX, die für den Offsetdruck in einer Druckerei vorbereitet sind. - Kosten - Voraussetzungen an das Dokument - Schnittmarken - Farbseparation - Testmöglichkeiten
68

Gestaltung von Dokumenten

Pönisch, Jens 27 October 2003 (has links) (PDF)
Hinweise zur Gestaltung von Dokumenten (wissenschaftliche Arbeiten, Bücher, Dokumentationen) - Makrotypographie
69

Nanosize latex particles via miniemulsion polymerization /

Anderson, Christopher D. January 2002 (has links)
Thesis (Ph. D.)--Lehigh University, 2002. / Includes bibliographical references and vita.
70

Poly(vinyl alcohol) stabilization of acrylic emulsion polymers using the miniemulsion approach /

Kim, Noma, January 2003 (has links)
Thesis (Ph. D.)--Lehigh University, 2003. / Includes bibliographical references and vita.

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