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991.
An easy-to-use, low-cost method for static fatigue testing of fibers in harsh environments was developed. Stresses greater than 550 ksi (3791 MPa) are attainable yet the specimen is insensitive to external shock. The method gave good comparative results when used to test indium-coated fused silica fibers under distilled water or 2M NaCl solution. 相似文献
992.
A.D. Brown 《Computer aided design》1984,16(5):249-252
The user interface of a diagram-drawing program, DIAG2, is described. The user is provided with three basic constructs: the straight line, the segment of a circle and the block of text. These constructs may be assembled into larger groups. Thus a diagram can be built up in a hierarchical manner by the user. DIAG2 performs the unwrapping operations necessary to decompose the diagram into a set of straight line segments, which can be output to the appropriate display peripheral. No intelligence is required in the graphics device itself. 相似文献
993.
994.
Agonist-stimulated phospholipases release arachidonate, but not 8,11,14-eicosatrienoate, from human endothelial cells. One
source of the arachidonic acid is deacylation of 1-alkyl-2-arachidonoyl-glycerophosphocholine, with subsequent conversion
of some of the resultant lysophospholipid to platelet-activating factor. This study has compared the distribution of incorporated
8,11,14-[14C]-eicosatrienoate in alkylacyl-GPC and diacyl-GPC with that of [14C]arachidonate synthesized endogenously by desaturation of the 8,11,14-[14C]eicosatrienoate. Cells were incubated for 24 or 48 hr with 8,11,14-[14C]eicosatrienoate, and the resultant mixture of14C-fatty acids in the cellular lipids was characterized by gas chromatography. The choline phospholipids were then separated,
hydrolyzed with phospholipase C and derivatized to diradylbenzoates. Gas chromatographic analysis indicated extensive incorporation
of [14C]eicosatrienoate, as well as [14C]arachidonate, into alkylacyl-GPC. Although the ratio of esterified [14C]arachidonate to [14C]eicosatrienoate was greater in alkylacyl-GPC than in diacyl-GPC, the enrichment with [14C]arachidonate was far less than the ratio of arachidonate/eicosatrienoate released from these cells. These results thus support
the hypothesis that the acyl specificity of polyunsaturated fatty acid release is provided by the agonist-stimulated phospholipase
A2 rather than the composition of the alkylacyl-GPC. 相似文献
995.
Eric Jungermann B. C. Brown J. J. McBride 《Journal of the American Oil Chemists' Society》1963,40(2):41-43
The reaction of olefins with phosphorus trichloride in the presence of aluminum chloride was recently reported to result in
phosphorus-containing acids or acid chlorides of the type
This new phosphorylation reaction was extended to fatty acid derivatives containing olefinic double bonds, such as methyl
oleate, oleonitrile, oleamide, N,N-dimethyloleamide, olive oil, oleylacetamide and oleyl alcohol. Phosphorylated fatty derivatives
were obtained in good yield in all cases.
Presented at the AOCS meeting in New Orleans, La., 1962. 相似文献
996.
A method for calculating electron transport in layered materials is described. It is applied to a problem of radiation damage in MOS capacitors irradiated with a Cu x-ray tube operated at 45 kV. The effects of photoelectron transport are found to be significant. A problem of energy deposition in x-ray lithography is also discussed. The dose in the SiO2 gate is found to be about equal to that in the x-ray photoresist. Electron transport effects are found to be small in this lithography problem. 相似文献
997.
Vinsel Anne; Brown Barbara B.; Altman Irwin; Foss Carolyn 《Canadian Metallurgical Quarterly》1980,39(6):1104
Examined privacy regulation in terms of (a) mechanisms used by college students to make themselves more or less accessible to one another; (b) dormitory room decorations; and (c) the relationships between privacy regulation, personal displays, and short- and long-term adjustment to a university setting. 102 freshmen completed a questionnaire that assessed privacy mechanisms, satisfaction with the university, and other topics. Content analyses of photos of room decorations were also completed. Results at follow-up, over 1 yr later, show that Ss who had dropped out of the university had fewer and less effective privacy mechanisms, were less satisfied with university life, and were less active in various campus events. Although dropouts tended to decorate their rooms more than did Ss who were still enrolled, their decorations showed less diversity and less commitment to the university setting. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
During the examination of the colon by fibre-optic colonoscopy in 200 consecutive patients it was possible to reach the caecum or suspected lesion in 80% of cases. Careful bowel preparation, sedation and detailed attention to techniques described are necessary for safe and successful performance of this procedure. In 85% of examinations, colonoscopy produced positive results including the definition of uncertain radiological lesions in 45 patients, finding of a cause for rectal bleeding not shown on barium studies in 15 patients, the assessment of inflammatory bowel disease in 28 patients, and the removal of polyps in 40 patients. Important was the finding of a normal colon in 49 cases, which obviated unnecessary surgery. Colonic perforation occurred in 2 patients. The limitations and complications of the procedure must be realised, but it is concluded that the colonoscope provides a valuable and effective means of diagnosis and therapy of lesions in the large bowel. 相似文献
999.
1000.
Stephen K. Brown 《Polymer International》1980,12(1):24-30
Fracture properties of a wide range of filled unsaturated polyester resin composites have been investigated with respect to filler size, shape, loading and adhesion to the matrix resin. Mechanisms are proposed for the fracture behaviors found, based on geometrical considerations of interacting filler particles and stress concentrations which result from them. 相似文献