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排序方式: 共有1035条查询结果,搜索用时 15 毫秒
951.
Although the importance of religion in the lives of older African Americans is well documented, this is the 1st study to examine the relations between religious involvement and psychological well-being among a sample comprised exclusively of older African Americans. Eighty-six participants completed multidimensional measures of religious involvement (J. S. Levin, R. J. Taylor & L. M. Chatters, 1995) and well-being (C. D. Ryff & M. J. Essex, 1992). Results indicated that several dimensions of religious involvement (Organizational, Nonorganizational, and Subjective) were associated with several dimensions of psychological well-being (Positive Relations with Others, Self-Acceptance, Environmental Mastery, Purpose in Life, and Personal Growth). Recommendations for future research and implications for counseling are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
952.
OH Frazier 《Canadian Metallurgical Quarterly》1994,58(5):1309-1310
953.
Fluoride was found to affect the production of the bacterial IgA1 protease but to have no effect on IgA1 protease activity. The concentrations of fluoride that do affect Streptococcus sanguis growth and IgA1 protease production are higher than those normally seen in vivo under normal circumstances. The concentrations of fluoride in dental plaque following use of a fluoride rinse or dentifrice would be sufficient to reduce Strep. sanguis IgA1 protease production. 相似文献
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957.
P. J. Frazier F. A. Leigh-Dugmore N. W. R. Daniels P. W. Russell Eggitt J. B. M. Coppock 《Journal of the science of food and agriculture》1973,24(4):421-436
The mechanical development of dough has been followed by measurement of the relaxation time of dough samples after mixing to various levels of work input. Parallel determinations of free and bound lipid have also been made. When doughs were mixed in air, addition of full-fat, enzyme-active soya bean flour (subsequently referred to as “soya flour”) resulted in an increase in relaxation time, particularly at higher work levels. The magnitude of this improvement increased with increasing work input and was dependent on the rate of work input. Addition of soya flour also enabled a higher level of mechanical work to be introduced before dough breakdown occurred. When doughs were mixed under nitrogen, or when the soya flour was heat denatured, no change in the rheological properties compared with the respective control doughs was found. The release of bound lipid, which occurred during dough development in air in the presence of soya flour, could also be induced by adding purified lipoxygenase to the dough, together with linoleic acid as a substrate. This resulted in rheological changes similar to those observed using soya flour. However addition of enzymically pre-peroxidised lipid to doughs mixed in nitrogen was without effect on relaxation times. These findings suggest that lipid release is linked with structural changes in dough protein and provide further support for a mechanism of coupled oxidation of protein -SH groups by lipoxygenase. 相似文献
958.
BW Schumacher 《Canadian Metallurgical Quarterly》1991,44(11):7047-7052
959.
M. Gupta J. Juarez-Islas W. E. Frazier F. A. Mohamed E. J. Lavernia 《Metallurgical and Materials Transactions B》1992,23(6):719-736
In the present study, the microstructure, thermal stability, and elevated temperature mechanical behavior of Al-Ti-SiCP metal matrix composites (MMCs) processed by spray atomization and codeposition were investigated. The evolution of the microstructure
of the spray-deposited material before and after thermal annealing was studied using X-ray diffractometry, transmission electron
microscopy (TEM), scanning electron microscopy (SEM), and optical microscopy. The thermal stability of the spray-deposited
materials was determined by monitoring the changes in hardness after isochronal thermal anneals at various temperatures. The
results of X-ray and microanalysis studies revealed the presence of a supersaturated solid solution of Ti in α Al in the spray-atomized
and codeposited material, with Ti concentrations in the 0.8 to 1.1 wt pet range. The formation of an extended solid solution
was discussed in light of the cooling rates present during atomization and, subsequently, during deposition. Regarding mechanical
behavior, the present results suggest that the as-spray deposited and hot extruded Al-Ti matrix is thermally stable up to
a temperature of 400 °C and that the excess solid solubility of Ti in a Al, resulting from the rapid quench during processing,
is maintained up to a temperature of 300 °C. The elevated-temperature mechanical properties of the hot extruded spray-deposited
materials were studied following a 100-hour exposure at 250 °C, 350 °C, and 450 °C; the roomtemperature mechanical properties
were also determined. Results show that the elevated-temperature yield strength of the spray-deposited and extruded materials
compared favorably to those of an equivalent alloy made by powder metallurgical materials, were superior to those of the ingot
material, but were inferior to those of mechanically alloyed Al-Ti materials. In addition, TEM studies showed no evidence
of interfacial reactions at the Al-Ti/SiCP interface.
This article is based on a presentation made in the symposium “Spray Processing Fundamentals: Coating and Deposition” presented
as part of the 1990 TMS Fall Meeting, October 9, 1990, in Detroit, MI, under the auspices of the TMS Synthesis and Analysis
in Materials Processing Committee. 相似文献
960.