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71.
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
72.
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
73.
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
74.
75.
76.
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
77.
Ernest W. Dewing 《Metallurgical and Materials Transactions B》1991,22(2):177-182
Consideration of the mechanism of loss of current efficiency (CE) leads to a form of equation which is simple, likely to give
reasonable extrapolation beyond the range where experimental data are available, and convenient for responding to practical
questions. With coefficients generated from plant experiments (performed by others), the equation is log (pct loss of efficiency)
= 0.0095 (superheat) -−0.019 (pct A1F2) − 0.060 (pct LiF) + const where superheat is the difference (in °C) between cell temperature and the pseudo-binary eutectic
temperature with A12O3, and pct A1F3 is excess A1F3. The coefficient for CaF2 is zero. The constant is characteristic of the cell design. The question of reconciling the values of the coefficients with
literature data on the solubility of Al in cryolite melts and current theories of loss of efficiency is discussed.
Formerly Principal Scientist, Kingston Laboratory, Alcan International Ltd., Kingston, ON K7L 5L9, Canada, is retired. 相似文献
78.
79.
Soluch W Brzozowski E Lysakowska M Sadura J 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(11):2469-2474
Mass density, dielectric, elastic, and piezoelectric constants of bulk GaN crystal were determined. Mass density was obtained from the measured ratio of mass to volume of a cuboid. The dielectric constants were determined from the measured capacitances of an interdigital transducer (IDT) deposited on a Z-cut plate and from a parallel plate capacitor fabricated from this plate. The elastic and piezoelectric constants were determined by comparing the measured and calculated SAW velocities and electromechanical coupling coefficients on the Z- and X-cut plates. The following new constants were obtained: mass density p = 5986 kg/m(3); relative dielectric constants (at constant strain S) ε(S)(11)/ε(0) = 8.6 and ε(S)(11)/ε(0) = 10.5, where ε(0) is a dielectric constant of free space; elastic constants (at constant electric field E) C(E)(11) = 349.7, C(E)(12) = 128.1, C(E)(13) = 129.4, C(E)(33) = 430.3, and C(E)(44) = 96.5 GPa; and piezoelectric constants e(33) = 0.84, e(31) = -0.47, and e(15) = -0.41 C/m(2). 相似文献
80.
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