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71.
Sliding tests have been carried out using a variety of soft metal and nonmetal pins on a rotating steel disk at speeds up to 150 m/s. A new high-speed friction apparatus in which the normal force, the friction force and the friction coefficient are recorded, was used. In general, the wear rate increased drastically, and the friction coefficient decreased moderately as the sliding speed was raised, these changes being especially pronounced when pin materials of low melting temperature were used. The friction data are in good agreement with those obtained by others using the pin-on-disk geometry. However, although in many cases the interface reached the melting temperature of the lower melting sliding material, the very low friction coefficient values of under 0.05 reported by some investigators were not reached. 相似文献
72.
Reports an error in "An introduction to the special section on U.S. Military operations: Effects on military members' partners and children" by Michelle L. Kelley and Ernest N. Jouriles (Journal of Family Psychology, 2011[Aug], Vol 25[4], 459-460). An author’s name cited in the text and the reference section was misspelled as Knoblock. The correct reference is Knobloch, L. K., & Theiss, J. A. (2011). Depressive symptoms and mechanisms of relational turbulence as predictors of relationship satisfaction among returning service members. Journal of Family Psychology, 25, 470–478. The online versions of this article have been corrected. (The following abstract of the original article appeared in record 2011-17889-001.) The deployment of U.S. military personnel to global hot spots, whether as combatants or as peacekeepers, has increased attention to the psychological well-being of military personnel and their family members. Despite the growing awareness that deployments have reverberating effects on all family members, theoretical explanations and empirical research on the impact of deployment on couple, family, and child adjustment, factors that serve to protect families from the demands of military employment, and effective methods of treating the mental health needs of military families are needed. The seven papers in this section increase our understanding of how the demands of U.S. military operations impact couples, family functioning, parenting, and child psychological adjustment and provide an additional resource for mental health professionals who work with these families. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
73.
Ernest Demaray 《Journal of the Society for Information Display》2001,9(1):15-18
A sputtered microcrystalline‐silicon thin film deposited on unannealed Corning Code 1737 glass has been shown to transform to polycrystalline material after excimer‐laser annealing at low energy densities, and below the full‐melt threshold. The homogeneous large‐grain polysilicon films obtained show promise for high‐yield manufacturing of large‐area LTPS displays. The material properties of the films will be presented and the properties of devices fabricated in the films will be discussed. 相似文献
74.
Social comparison processes and academic achievement: The dependence of the development of self-evaluations on friends' performance. 总被引:1,自引:0,他引:1
The purpose of this study was to examine the role of social comparison processes in children's self-evaluations. Children's aptitudes to gauge their self-evaluations of their abilities in school activities (i.e., perceived academic competence) on the basis of their actual performance depended on how well their reciprocated friends performed academically. Self-evaluations of performance were not affected when the comparison was based on levels of nonreciprocated friends' achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Describes the Blind Learning Aptitude Test (BLAT) and presents age norm data. Use of BLAT (T. E. Newland, 1977) in rehabilitation assessment with regard to academic learning potential is considered. The high correlation of BLAT performance with measured educational achievement and the cultural neutrality of BLAT indicate its usefulness in assessing basic cognitive learning potential of rehabilitation clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Cake filtration theory and practice 总被引:2,自引:0,他引:2
Ernest Mayer 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2000,80(1-3):233-236
77.
Bert H. Lincoln Gordon D. Byrkit Ernest W. Nelson 《Journal of the American Oil Chemists' Society》1940,17(4):73-81
Conclusion The use of fats, fatty oils, and derivatives is extensive in the petroleum industry to improve its lubricants in their wetting
ability or oiliness. Fats and their derivatives serve to carry active elements such as chlorine, sulfur, and phosphorus for
the improvement of load-carrying capacity, resistance to oxidation, inhibiting corrosiveness, and preventing wear during use.
Greases are compounded from whole fats and fatty acids which serve under suitable conditions to gel lubricating oil and thus
fulfill lubricating requirements which the liquid oils cannot themselves satisfy. Greases and their components may be tested
for skin hardening in storage by means of an oxygen absorption test which distinguishes between satisfactory and unsatisfactory
ingredients and products.
Presented in a symposium on the Industrial Applications of Fats & Fatty Acids at the Fall Convention of the American Oil Chemists
Society, Chicago, Oct. 1939. 相似文献
78.
79.
80.
Ernest W. Dewing 《Metallurgical and Materials Transactions B》1990,21(2):285-294
Literature data are reviewed to derive enthalpies and entropies of Na3AlF6 and NaF, and they are combined with electrochemical and equilibrium data to yield free energies of formation of Na3AlF6 from the constituent fluorides. Liquidus data and measurements of the Na content of Al in equilibrium with the melts then
enable the calculation of the free energy of formation, enthalpy, and entropy of all mixtures liquid at 1293 K. In stoichiometric
Na3AlF6 at 1293 K, aNaF =0.37 and aAlF
3 = 4.9 × 10−4. The activity coefficient of Na in dilute solution in Al is given byRT ln γNa = (40 967 + 9.480 T) J. At 1293 K the partial pressure of NaAlF4 is given by pNaA1F4/bar = 27aNaF . aAif
3- A heavier species— suggested to be NaAl3F10—is present in the vapor above AlF3-rich melts. 相似文献