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991.
992.
O. A. Dolgopolov 《Glass and Ceramics》2005,62(5-6):155-156
Magnetic roll separators on rare-earth magnets are suitable for removing iron impurities from various materials. The advantages
of these magnetic separators over traditional ones are demonstrated.
__________
Translated from Steklo i Keramika, No. 5, p. 33, May, 2005. 相似文献
993.
994.
995.
We formulate a class of difference schemes for stiff initial-value problems, with a small parameter ε multiplying the first derivative. We derive necessary conditions for uniform convergence with respect to the small parameter ε, that is the solution of the difference scheme uih satisfies |uih−u(xi)| Ch, where C is independent of h and ε. We also derive sufficient conditions for uniform convergence and show that a subclass of schemes is also optimal in the sense that |uih−u(xi)| C min (h, ε). Finally, we show that this class contains higher-order schemes. 相似文献
996.
997.
Bordini Ernest J.; Tucker Jalie A.; Vuchinich Rudy E.; Rudd Edmund J. 《Canadian Metallurgical Quarterly》1986,95(4):346
Assessed whether women self-handicap with alcohol consumption prior to engaging in a social evaluation task, which may be more relevant to their self-esteem than the intellectual tasks used in past self-handicapping studies on substance use. 113 women (aged 19–32 yrs), who were evaluated as normal drinkers, performed either a solvable or an insolvable social judgment task and then received either success feedback or no feedback. Ss received access to alcoholic and nonalcoholic beverages while awaiting a retest. The study terminated before the retest. The self-handicapping hypothesis that noncontingent success would produce relatively greater alcohol consumption was not supported. Regardless of feedback, insolvable test Ss consumed more alcohol than did solvable test Ss. Findings suggest that the hypothesis may be limited as a general model of alcohol consumption in both sexes. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
An asymptotically efficient autoregressive moving-average (ARMA) spectral estimator is presented, based on the sample covariances of observed time series. The estimate of the autoregressive (AR) part is shown to be identical to the optimal instrumental variable (IV) estimator in [7] although derived here using a different approach. The moving-average (MA) spectral parameter estimate is new. 相似文献
999.
Steam volatile fractions obtained from three commercial mayhaw cultivars and two native selections were analyzed by GC and GC/MS. Twenty-four compounds were identified. The nine major components, which comprised 70–80% of the volatile fraction, were hexanal, butyl acetate, (E)-2-hexenal, butyl butyrate, linalool, butyl hexanoate, methyl octanoate, pentyl hexanoate, and hexyl hexanoate. Minor constituents included eight esters, four terpenes, two benzenoid compounds and (E)-2-hexenol. 相似文献
1000.