• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1146
  • 665
  • 228
  • 226
  • 154
  • 107
  • 78
  • 34
  • 21
  • 15
  • 13
  • 10
  • 10
  • 10
  • 10
  • Tagged with
  • 3225
  • 485
  • 305
  • 284
  • 246
  • 243
  • 206
  • 191
  • 190
  • 177
  • 167
  • 165
  • 163
  • 158
  • 153
  • 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.
71

The effects of environmental aging on the durability of glass/epoxy composites

Kajorncheappunngam, Somjai. January 1999 (has links)
Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xv, 229 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 197-203).
72

Enhanced design for oxy-fuel fired batch tanks using CFD methods

Kang, Guosheng. January 2000 (has links)
Thesis (Ph. D.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains x, 153 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 150-153).
73

2D PASS-CPMG a new NMR method for quantifying structure in non-crystalline solids /

Vickers, Samantha G., January 2009 (has links)
Thesis (M.S.)--Ohio State University, 2009. / Title from first page of PDF file. Includes vita. Includes bibliographical references (p. 32-34).
74

Glass manufacturing centre

Chan, Kwok-keung, January 1994 (has links)
Thesis (M.Arch.)--University of Hong Kong, 1994. / Includes special report study entitled : Technology of glass and glass constructions. Includes bibliographical references. Also available in print.
75

The expression of emotions /

Chung, Hweawon. January 2006 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 2006. / Typescript. Includes bibliographical references.
76

Compostos luminescentes em matrizes macroporosas de sílica obtidas por tratamento hidrotérmico a partir de vidro pyrex

Sigoli, Fernando Aparecido [UNESP] 19 July 2001 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-07-19Bitstream added on 2014-06-13T20:06:32Z : No. of bitstreams: 1 sigoli_fa_dr_araiq.pdf: 3331714 bytes, checksum: f15f140dd71661951c9acd489ff18e44 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste trabalho, obteve-se uma matriz porosa com alto teor de sílica a partir de vidros Pyrex® utilizando-se o tratamento hidrotérmico. A matriz porosa é formada principalmente por dois processos: (i) reação da água no estado supercrítico com a rede vítrea e, (ii) separação e lixiviação de fases. A matriz apresenta-se macroporosa, possuindo também baixa percentagem de micro e mesoporos. Através de técnicas espectroscópicas verifica-se que a matriz apresenta grupos silanóis de superfície, os quais foram utilizados em reações de funcionalização. A espectroscopia de ressonância magnética nuclear de 29Si, MAS RMN, indica a presença de grupos ordenados, (SiO)4Si, no interior da matriz e do grupo (SiO)3Si(OAl). Os espectros de 29Si, CPMAS RMN, indicam que a matriz porosa é constituída de átomos de silício localizados em dois ambientes químicos diferentes, (SiO)3Si(OH), e (SiO)4Si. Pelo espectro de 27Al MAS RMN confirma-se a presença do grupo Al-O-Si, o qual é responsável pela formação de sítios ácidos de Brönsted. Pela análise dilatométrica verifica-se que a contração máxima da matriz foi de 6% em 1365oC, aumentando a densidade do material, o tamanho médio dos poros, devido a consolidação de micro e mesoporos, diminuindo assim a área superficial. A matriz cristaliza-se em 950oC como α-cristobalita pertencente ao grupo espacial P41212. A matriz obtida foi então utilizada como suporte para complexos luminescentes. O complexo diaquatris(tenoiltrifluoroacetonato)európio(III), [Eu(tta)3(H2O)2], impregnado ou ancorado na matriz, apresenta emissões com alargamento não-homogêneo indicando que há interações entre o complexo e a superfície da matriz... / In the present work, porous silica matrix has been obtained from Pyrex glass by hydrothermal treatment under saturated steam condition. The formation process was principally investigated using scanning and transmission electron microscopies and Raman spectroscopy. The results indicate that the process of phase separation takes place on edge of vitreous sample at lower temperature than of glass-transition temperature at room atmosphere. This process occurs due to the glass hydration by hydrothermal treatment that diminishes both viscosity and glass transition temperature. The segregated orthoborate phase was leached out by water in supercritical condition. The formation and leaching of this phase together with essential reactions between water and silica at supercritical condition contribute to obtain a porous silica matrix. The matrix has a high percentage of porosity, an interconnected macroporous structure, a low percentage of micro and mesopores and also a good thermal stability. It is non-crystalline and after thermal treatment it presented X-ray pattern characteristic of cristobalite and a low contraction of volume. The chemical analysis shows a high concentration of silicon and low concentrations of aluminum and boron. The chemical environments of silicon and aluminum atoms into the porous silica matrix were investigated by solid state NMR spectroscopy. The 29Si MAS NMR spectrum exhibits a broad signal at -110 ppm, typical of an ordered silica phase. The chemical nature of surface was better understood with application of the 1H - 29Si CPMAS NMR technique. This technique leaded to a strong and selective... (Complete abstract, click electronic access below)
77

Drawing and glass : integrating theoretical and contemporary drawing issues with studio glass practice

Grant, Jennifer January 2012 (has links)
This research examines established and emerging practical methods and theoretical ideas in contemporary drawing in relation to studio glass. The Studio Glass Movement, encompassing both applied and fine art practice, originated in the 1950’s and, despite rapid advancements in the subject, glass is still considered an emergent material when compared to most other studio processes. For this reason existing and long established practices in drawing, developed in relation to other materials, may not be as effective in realising or exploring those qualities which are particular to glass, whether aesthetic, technical or philosophical. Parallel to this are rapid changes happening within the field of contemporary drawing as a subject in its own right, which influence the wider context in which studio glass engages. In this research the use of empirical methods provide working examples of how drawing and glass can be integrated, through the production of a body of new work supported by theoretical and contextual findings. The investigation is practice orientated, incorporating both practice led and practice based methodologies. The practice led theoretical research proposes a new drawing taxonomy in which dimension, notation, physiology and improvisation are understood as key components in the theory and practice of drawing. This is examined here in relation to glass as both a subject of drawing and as a material process. Identification and reference to contemporary issues in drawing come from a variety of sources, for example through the Drawing Research Network, contact with specialist drawing research hubs including Wimbledon School of Art and Loughborough University, specific exhibitions and attendance at related events and conferences . The practice based aspect uses facilities at the Glass Department, University of Sunderland and a drawing studio in Newcastle upon Tyne. The main area of exploration is concerned with the use of drawing integrated within kiln cast glass as differentiated from established practices such as engraving and stained glass which use drawing as a surface application to an existing glass body.
78

Nonequilibrium Relaxation and Aging Scaling Properties of the Coulomb Glass and Bose Glass

Shimer, Matthew Timothy 21 September 2011 (has links)
We use Monte Carlo simulations in order to investigate the density of states and the two-time density autocorrelation function for the two- and three-dimensional Coulomb glass as well as the Bose glass phase of flux lines in type-II superconductors. We find a very fast forming gap in the density of states and explore the dependence of temperature and filling fraction. By studying two scaling methods, we find that the nonequilibrium relaxation properties can be described sufficiently by a full-aging scaling analysis. The scaling exponents depend on both temperature and filling fraction, and are thus non-universal. We look at the trends of these exponents and found that as either the temperature decreases or the filling fraction deviates more from half-filling, the exponents reflect slower relaxation kinetics. With two separate interaction potentials, a comparison of relaxation rates and the gap in the density of states is made. / Ph. D.
79

Examining Gender Differences in Hitting the Glass Ceiling and Riding the Glass Escalator

Morris, Samantha A. 30 July 2010 (has links)
No description available.
80

Effects of Waste Glass Addition on the Properties of Fired Clay Brick

Federico, Lisa 06 1900 (has links)
The optimization of the production of fired clay brick is essential in order to maintain a sustainable industry in Ontario. While there exists areas for improvement of the properties of bricks used in severe climates, concerns including non-renewable resource depletion, increasing energy costs, and waste management have become increasingly important in Canadian and global industries. One method to address these concerns is the use of waste additives as fluxing agents in bricks. While a fluxing agent reduces the firing temperature required for sintering of the brick and improves properties, the use of a waste additive can decrease the dependency of the industry or non-renewable resources such as mined clay or crushed shale. Waste additives can improve strength durability, and absorptive properties, while decreasing firing temperature, and diverting waste from landfills. A testing program was developed to determine the effects of several variables in brick production, including extrusion and firing, and to investigate the effect of the addition of non-recycled waste glass in the properties of fired clay brick. The addition was varied in the particle size of the waste glass and the percentage by mass of additive. The effects of waste glass addition were determined in terms of absorption, strength, and freeze-thaw durability of the individual specimens. Microstructure was also investigated using SEM images and mercury intrusion porosimetry to determine the effect on pore structure and vitrified matrix of the bricks. The results of the testing program determined an optimal addition of waste glass, and the expected effects of the implementation of this addition to the production of fired clay brick in an industrial setting. / Thesis / Master of Applied Science (MASc)

Page generated in 0.0338 seconds