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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.
131

Evaluation of e-beam SiO2 for MIM application

Guo, Wei Unknown Date
No description available.
132

Modeling and optimization of molecular beam epitaxy for III-V compound semiconductor growth

Lee, Kyeongkyun 12 1900 (has links)
No description available.
133

Solid source molecular beam epitaxial growth of 155-um InAsP/InGaAsP edge-emitting lasers

Dagnall, Georgiana 08 1900 (has links)
No description available.
134

Three dimensional measurement data analysis in stereolithography rapid prototyping

Tucker, Thomas Marshall 12 1900 (has links)
No description available.
135

A method for understanding and predicting stereolithography resolution

Sager, Benay 05 1900 (has links)
No description available.
136

Chemical beam epitaxial growth of (001) ZnS

Shen, Xiu-Li 08 1900 (has links)
No description available.
137

Comparison of Current Almond Pasteurization Methods and Electron Beam Irradiation as an Alternative

Cuervo Pliego, Mary 2011 December 1900 (has links)
Two outbreaks of salmonellosis were linked to the consumption of raw California almonds in 2001 and 2004. Current federal regulations mandate that all almonds grown in California are to be treated with a process that results in a 4-log reduction of Salmonella. Since four out of the five approved technologies to pasteurize almonds rely on the application of heat to control Salmonella, the evaluation of alternative technologies against heat resistant Salmonella Senftenberg was imminent. In this study, almonds that were inoculated with S. Enteritidis PT 30 and S. Senftenberg, were treated with electron beam irradiation (e-beam), blanching and oil roasting. The thermal death time (D-value) for S. Enteritidis PT 30 when treated with e-beam was 0.90 kGy, 15 s when subjected to blanching at 88 degrees C, and 13 s when treated with oil at 127 degrees C. Irradiation and thermal resistance of S. Senftenberg was not significantly different (P > 0.05) from S. Enteritidis PT 30. The commercial application of e-beam as a pathogen intervention was assessed through Monte Carlo simulations (MCS) and experimental measurements. The sensory characteristics of almonds commercially treated by e-beam, blanching and roasting were assessed by a consumer panel. Irradiated and blanched almonds did not differ in consumer overall like (P > 0.05). Bitterness and rancidity attributes of irradiated almonds were between a "dislike slightly" and "dislike moderately", whereas blanched and roasted almonds were between "neither like nor dislike" and "like slightly". Almonds commercially irradiated, blanched and roasted were subjected to an accelerated shelf-life test (ASLT) evaluating percentage free fatty acids, peroxide value, and 2-thiobarbituric acid reactive substances (TBARs). No clear differences between treatments were observed at any given point in time in any of the chemical tests. A gas chromatography-mass-spectrometry-olfactometry (MDGC-MS-O) technology was used to compare full aroma and flavor profiles from raw and e-beam irradiated almonds. Differences in the aroma/odor profile and the taste analysis revealed that the difference between raw and irradiated almonds is extremely subtle. In conclusion, e-beam may be a feasible technology to control Salmonella in almonds if used at low doses, as a part of a series of interventions.
138

Behaviour of columns in sub-frames with semi-rigid joints

Rifai, Abdussalam Mahmud January 1987 (has links)
The behaviour of limited subassemblages with flexible beans and semi-rigid beam to column connections was studied using a computer program in which the finite element method was employed in a non-linear analysis which accounts for the presence of semi-rigid connections and the inelastic behaviour of frames. The program accounts for many other factors such as initial imperfections and residual stresses. The theoretical background to the present computer program has been presented along with the program layout. The program was used to simulate some of the experimental results obtained from tests on rigidly and flexibly connected frames with different combinations of beam and column loads. The analytical results were found to compare reasonably well with the experimental results. The program was also used to simulate a series of I-shaped subassemblages that were tested at the University of Sheffield. Comparisons were made between the analytical and experimental results characterized by the maximum loads, load-deflection curves and load- moment curves. Good agreement was obtained between the analytical and the experimental load-deflection curves for all of the cases considered. The general trends of the measured and calculated load- moment curves for most cases were found to be comparable. The recommendations given in B35950 for the design of columns in simple construction were applied to all cases in the last series and were found unconservative in the cases of balanced loading and conservative in the cases of unbalanced loads. A limited parametric study was conducted to study the effects of semi-rigid joints, bean flexibility and type of loading. In this study, an I-shaped subassemblage was analysed for different load types and different types of beam to column connections. A substantial effect was recognized due to the presence of semi-rigid connections whether or not a beam load was applied. Beam flexibility was also seen to affect the carrying capacity of the subassemblage under the action of column load only although this effect was less noticeable than that of the connection flexibility. The presence of beam load was found to result in an unexpected interaction curve which relates the total force in the column to the moment that is transmitted to the column's end. An almost linear relationship with negative gradient seems to exist between the column and beam loads. It is pointed out that all the findings of the present study are based on the range of cases considered in the parametric study but it is suggested that they serve as indicators to the behaviour of any the subassemblage under axial load oniy or axial load combined with beam loads. A few recommendations for future work are presented.
139

Studies into the growth and doping of zinc selenide and zinc cadmium selenide

Stewart, Helen January 1996 (has links)
No description available.
140

Evaluation of steel I-section beam and beam-column bracing requirements by test simulation

Lokhande, Ajinkya M. 12 January 2015 (has links)
The ANSI/AISC 360-10 Appendix-6 provisions provide limited guidance on the bracing requirements for beam-columns. In cases involving point (nodal) or shear panel (relative) lateral bracing only, these provisions simply sum the corresponding strength and stiffness requirements for column and beam bracing. Based on prior research evidence, it is expected that this approach is accurate to conservative when the requirements can be logically added. However, in many practical beam-column bracing situations, the requirements cannot be logically added. This is because of the importance of the brace and transverse load position through the cross-section depth, as well as the fact that both torsional and lateral restraint can be important attributes of the general bracing problem. These attributes of the bracing problem can cause the current beam-column bracing requirement predictions to be unconservative. In addition, limited guidance is available in the broader literature at the current time regarding the appropriate consideration of combined lateral and torsional bracing of I-section beams and beam-columns. Nevertheless, this situation is quite common, particularly for beam-columns, since it is rare that separate and independent lateral bracing systems would be provided for both flanges. More complete guidance is needed for the proper consideration of combined bracing of I-section beams and beam-columns in structural design. This research focuses on a reasonably comprehensive evaluation of the bracing strength and stiffness requirements for doubly-symmetric I-section beams and beam-columns using refined Finite Element Analysis (FEA) test simulation. The research builds on recent simulation studies of the basic bracing behavior of beams subjected to uniform bending. Various cases of beam members subjected to moment gradient are considered first. This is followed by a wide range of studies of beam-column members subjected to constant axial load and uniform bending as well as axial load combined with moment gradient loading. A range of unbraced lengths are considered resulting in different levels of plasticity at the member strength limit states. In addition, various bracing configurations are addressed including point (nodal) lateral, shear panel (relative) lateral, point torsional, combined point lateral and point torsional, and combined shear panel lateral and point torsional bracing.

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