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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.
161

Textiles in three dimensions : an investigation into processes employing laser technology to form design-led three-dimensional textiles

Matthews, Janette January 2011 (has links)
This research details an investigation into processes employing laser technology to create design-led three-dimensional textiles. An analysis of historical and contemporary methods for making three-dimensional textiles categorises these as processes that construct a three-dimensional textile, processes that apply or remove material from an existing textile to generate three-dimensionality or processes that form an existing textile into a three-dimensional shape. Techniques used in these processes are a combination of joining, cutting, forming or embellishment. Laser processing is embedded in textile manufacturing for cutting and marking. This research develops three novel processes: laser-assisted template pleating which offers full design freedom and may be applied to both textile and non-textile materials. The language of origami is used to describe designs and inspire new design. laser pre-processing of cashmere cloth which facilitates surface patterning through laser interventions in the manufacturing cycle. laser sintering on textile substrates which applies additive manufacturing techniques to textiles for the generation of three-dimensional surface patterning and structures. A method is developed for determining optimum parameters for laser processing materials. It may be used by designers for parameter selection for processing new materials or parameter modification when working across systems.
162

Laser studies of species involved in plasma etching processes

Booth, J. P. January 1988 (has links)
No description available.
163

Optically pumped nitric oxide : a line-tunable VUV laser

Haxell, Adrian Mathew January 1994 (has links)
No description available.
164

U.V. and X-ray preionised high-pressure CO←2 lasers and line narrowing for spectroscopic studies

Raouf, Dayah Noori January 1987 (has links)
No description available.
165

Folded RF-excited CO←2 waveguide lasers

Jackson, Paul Edward January 1988 (has links)
No description available.
166

Observations of gains in the extreme ultraviolet

Shorrock, L. D. January 1983 (has links)
No description available.
167

Development and interaction of excimer laser with tissue

Al-Dhahir, Rashid K. January 1989 (has links)
No description available.
168

Mode control and tunability in Rf-excited CO2̲ waveguide lasers

Hill, C. A. January 1986 (has links)
No description available.
169

The development of a laser detonator system

Bowden, Mike January 2015 (has links)
Laser detonators offer several advantages over traditional electrical detonators, such as exploding bridgewire and slapper detonators, in terms of both safety and performance. Laser detonators remove the electrical conduction path to the energetic material, providing immunity from threats such as electrostatic discharge and lightning. A larger separation between the initiating energy source and the explosive devices is possible, up to several tens of metres, compared to a few metres for electrical slapper detonators. A laser detonator system has been developed, with laser-driven flyer plates used to shock initiate the explosive. All aspects of the system, including coupling into an optical fibre, used to transmit the laser energy to the detonator, the optical fibre, the flyer plate launch and acceleration and subsquent shock into the explosive, and the explosive initiation have been investigated, with an understanding of the underlying principles and processes developed. Shock initiation of two secondary explosives, hexanitrostilbene and pentaerythritol tetranitrate, has been studied at extremely high shock pressures, comparable to the detonation pressure, and the critical energy fluence required for initiation established. The laser detonator system is robust and optimised, with design tools developed to enable efficient design of future systems.
170

Využití a omezení metod laserové ablace ICP-MS v geovědních disciplínách / Use and limitations of laser ablation ICP-MS in geoscience applications

Míková, Jitka January 2011 (has links)
This dissertation contributes to applications of laser ablation plasma source mass spectrometry (LA ICP-MS) in Earth sciences. The primary goal of the thesis is to address some of the fundamental processes related to laser ablation of solid samples that result in decoupling of elements during laser ablation ICP-MS analysis. Better understanding of mechanisms that cause the elemental fractionation and matrix effects is necessary before the accuracy and precision of laser ablation ICP-MS analyses can be improved. The chemical and phase compositions of particles produced by laser ablation (266 nm Nd:YAG) of silicate NIST glasses and zircon were studied by SIMS and HR-TEM techniques with a particular focus on Pb/U fractionation. This is of great importance in geology as the Pb/U elemental fractionation hampered the precision and accuracy of the measured accessory mineral ages. The data suggest that chemical composition and mineralogy of particles produced at the ablation site during laser ablation differs from the original sample and varies with their size. This can result in elemental fractionation (non-stochiometric sampling) in material delivered to the ICP-MS for quantitative analysis. Evidence of the element fractionation is preserved in chemically zoned ejecta deposited around the ablation pit....

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