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971.
David C. Apperley Robin K. Harris Gregory L. Marshall Derek P. Thompson 《Journal of the American Ceramic Society》1991,74(4):777-782
The 29 Si MAS NMR spectra of the 2H, 4H, 6H, and 3C polytypes of silicon carbide are presented. An attempt is made to correlate differences in the chemical shifts with local atomic environment. The results of the analysis of the spectra of pure polytypes are used as a basic for the interpretation of the spectra of mixed polytypes and a discussion of the crystallinity and impurity levels of different samples. Carbon-13 chemical shifts obtained from spectra of the same polytypes are also tabulated. 相似文献
972.
973.
974.
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 12, pp. 16–20, December, 1992. 相似文献
975.
What does keeping one's eye on the ball mean? 总被引:2,自引:0,他引:2
976.
Observed visuographic and paranoid symptomatology in 26 dentists (mean age, 49.9 yrs) with elevated mercury levels. Neuropsychological functions were assessed with measures such as the Wechsler Adult Intelligence Scale (WAIS), the Bender-Gestalt Test, and the SCL-90 (Revised). Although the observed changes were mild, their presence suggests subtoxic hazards associated with dental practice and underscore a continual need for maintaining mercury hygiene. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
977.
V. M. Markevich T. A. Beilinova V. I. Chernyi A. S. Erofeeva A. É. Chikhachev V. E. Baburov V. P. Zharko S. L. Shcherbak E. N. Vasilenko V. F. Movchan A. F. Dudnik 《Metallurgist》1988,32(9):308-310
All-Union Scientific-Research Institute of Pipes (VNITI). Il'ich Zhdanov Metallurgical Combine. Translated from Metallurg, No. 9, pp. 39–40, September, 1988. 相似文献
978.
979.
Steimann F. Hayde M. Panzenbock B. Adlassnig K.-P. Pollak A. 《IEEE engineering in medicine and biology magazine》1994,13(5):705-709
ONSET derives its diagnosis from the combined evidence of contemporaneous and successive findings, which is in accordance with the behaviour of a clinician. Although it does not increase the diagnostic capabilities in principle, i.e., it cannot perform better than an expert reasoning on the basis of the same knowledge, computational power can be exploited to perform the matches and combine the results with greater precision, resolution, reliability, and transparency. Fundamental improvements of diagnosis, however, can only be expected from better serological tests or increased testing frequency. ONSET relies on domain knowledge explicated in a non-verbalized, analytical form. Knowledge representation-although mathematical-is intuitively clear and easy to conceive, making it equally accessible to both man and machine, and hence subject to objective evaluation and criticism 相似文献
980.
A Program for Outliers Elimination in Multidimensional Space (POEMS), which allows the user to eliminate outliers from training spaces as a prior step to any statistical study, is presented. Even though the program can be applied to any scientific field, the characteristics of POEMS makes it particularly suitable for 'series design' on Quantitative Structure-Activity Relationships studies. 相似文献