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991.
V. P. Levin Z. V. Goryacheva N. G. Erofeeva R. A. Khaikin L. Yu. Manevich 《Powder Metallurgy and Metal Ceramics》1982,21(12):915-918
Conclusions Experiments have established that there is an upper limit (D/d=max) of existence of the dynamic arch forming above the discharge orifice in the process of flow of a particulate material out of a hopper at certain discharge orifice diameter to particle diameter ratios. Within the limits of existence of the dynamic arch (between D/d=min and D/d=max) the fill height has no effect on the rate of discharge. Beyond the upper limit of existence of the dynamic arch the effect of fill height on the rate of discharge obeys an exponential law.Translated from Poroshkovaya Metallurgiya, No. 12(240), pp. 11–14, December, 1982. 相似文献
992.
Prigatano George P.; Parsons Oscar; Levin David C.; Wright Elizabeth; Hawryluk Garry 《Canadian Metallurgical Quarterly》1983,51(1):108
Previous research has demonstrated neuropsychological deficits in moderately to severely hypoxemic, chronic obstructive pulmonary disease (COPD) patients. The present article reports on the neuropsychological functioning of mildly hypoxemic COPD patients. 100 patients (mean age 61.5 yrs) and 25 controls (mean age 59.6 yrs) matched on relevant variables were given extensive neuropsychological tests including the WAIS, Wechsler Memory Scale, and Halstead-Reitan Neuropsychological Test Battery. Mild neuropsychological impairment was observed in the COPD Ss, with overall indexes of neuropsychological dysfunction correlating with resting partial pressure of oxygen. Depression and motivation to perform could not account for the results. Long-term reduced oxygen supply to the brain may account for these observed deficits. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Considerable attention has been given recently to an apparent 5.2% rise in cancer mortality, based on data for the first seven months of 1975 as reported to the National Center for Health Statistics (NCHS). Later data disclosed that the rise in crude total cancer mortality, while greater than in any recent year, is less than half of the 5.2% originally reported, and the rise in age-adjusted total cancer mortality, while less than 1%, is also higher than the average annual increase from 1968 to 1974. The Monthly Vital Statistics Report provides death rates not standardized for age, race, and sex, and does not include information for specific cancer sites. Therefore, although information in the Monthly Vital Statistics Report is useful for detecting sudden increases in mortality from acute epidemics, it is not appropriate for forecasting trends in cancer mortality. 相似文献
994.
Conclusions The assumption to the effect that the parameters of state of the air tract of an optical beam are identically the same in different closed rooms enables us to estimate the probability characteristics of the interference associated with refraction in photoelectric rectilinearity monitoring systems; this information may be used for calculating filters in these systems.Translated from Izmeritel'naya Tekhnika, No. 5, pp. 24–25, May, 1973. 相似文献
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996.
D. Levin N. Papamichael A. Sideridis 《Computer Methods in Applied Mechanics and Engineering》1977,12(2):201-218
Certain aspects concerned with the application of a conformal transformation method for the numerical solution of harmonic boundary value problems are considered. In particular, a procedure is decribed for removing the effects of singularities which are sometimes introduced by the transformations in the solution of the transformed problem. The transformed problem is then solved by a collocation technique. 相似文献
997.
We have successfully operated a CuCl laser in a metal tube in a hollow-cathode configuration. An average output of 400 mW was obtained with 0.06 percent "wall plug" efficiency. Excitation was by pulse burst with a repetition rate of 1-15 kHz within the burst. Despite the use of an unsealed vacuum system and cold windows the laser was operated for more than 300 h on a single charge of CuCl. The hollow-cathode configuration appears to offer significant improvement in mechanical strength and lasant conservation over Pyrex- or quartz-walled longitudinally pumped copper halide lasers. 相似文献
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