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991.
992.
993.
SC Bowden B Dodds G Whelan C Long P Dudgeon A Ritter C Clifford 《Canadian Metallurgical Quarterly》1997,19(5):755-762
Previous analyses of the Wechsler Memory Scale-Revised (WMS-R; Wechsler, 1987) have reported one-, two-, and three-factor solutions and raised questions about the validity of the visual memory subtests. These various findings may stem in part from different methods of analysis, and from the study of different participant samples. To address these issues, we analysed data from the WMS-R and a spatial maze test administered to 154 participants with a history of alcohol dependence. Results from confirmatory factor analysis supported the interpretation of three factors underlying the WMS-R subtests and the spatial maze score in this sample, namely, attention-concentration, immediate memory, and delayed recall. This result held despite the inclusion of the maze score which is a well-validated measure of visuo-spatial memory. 相似文献
994.
995.
G. P. Kurbskii G. P. Kayukova G. M. Usacheva R. I. Mutalapova E. V. Lifanova T. N. Yusupva G. V. Romanov 《Chemistry and Technology of Fuels and Oils》1992,28(6):309-313
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 6, pp. 7–9, June, 1992. 相似文献
996.
997.
The program LMSMVE performs robust regression analysis by using the method of the least median of squares. It also computes robust distances to locate leverage points, that is, outliers with respect to the set of independent variables. LMSMVE constructs plots of least median of squares residuals against robust distances. Both methods can tolerate up to half the data being outliers before they fail to give results that describe the bulk of the data. A complete system that operates directly on SYSTAT files is available for the IBM PC and compatibles; it includes a utility that converts ASCII files to SYSTAT format. 相似文献
998.
A. E. Gorodetskii A. V. Markin V. N. Chernikov A. P. Zakharov T. A. Burtseva I. V. Mazul N. N. Shipkov G. D. Tolstolutskaya V. F. Rybalko 《Atomic Energy》1997,82(6):448-462
Conclusions The conditions have been proposed for performing modeling experiments making it possible to predict the accumulation of hydrogen
isotopes in carbon materials which are in contact with a tokamak plasma acting as a source of particles having a flux density
of between 3×1016 and 3×1019 cm−2·sec−1. By analyzing the reemission fluxes formed in the stopping zone of the particles implanted from the plasma it is suggested
that the action of the plasma as regards the sorption of hydrogen is identical to that of annealing the material in an atmosphere
of hydrogen isotopes at a pressure of 1–103 Pa and a temperature of 1200–1700 K. The quantity of absorbed deuterium in POCO, UAM, RGT-B, and USB increases as the temperature
is lowered and the pressure is raised (1500 K, 0.66 Pa→1200 K, 133 Pa). As regards their sorption of deuterium, POCO, UAM,
and RGT behave similarly. There is a tendency for the sorption capacity of materials doped with boron to be reduced. In a
class of itself is the isotropic material USB, whose sorption capacity is a factor of 10–100 lower than that of undoped graphite.
The introduction into these materials of radiation-induced defects (T=300 K) by means of ion irradiation in the range 0.1–1 dpa results in a continuous rise in the deuterium sorption capacity
by a factor of 10–100 (up to 10−2 atomic fraction). The USB graphite demonstrates record low increments in the sorption capacity. In the fluence range identical
to 1–10 dpa the sorption capacity of carbon materials for hydrogen is almost constant. The process of the sorption of hydrogen
isotopes can be described as the filling of two ensembles of traps, deep traps which are difficult to access and readily accessible
Langmuir traps. In the RGT-B materials containing 0.1% of boron, the traps introduced by irradiation with 300-keV neon ions
vanish on annealing in a vacuum (T=1800 K, t=1 min).
Institute of Physical Chemistry, Russian Academy of Sciences.
SINTEZ Scientific and Technical Center, Scientific-Research Institute of Electrophysical Apparatus.
Graphite Scientific-Research Institute.
National Scientific Center, Kharkov Physicotechnical Institute. Translated from Atomnaya énergiya, Vol. 82, No. 6, pp. 448–464,
June, 1997. 相似文献
999.
1000.
Yu. E. Pivinskii P. V. Dyakin Ya. Yu. Pivinskii S. V. Vikhman 《Refractories and Industrial Ceramics》2003,44(5):309-313
General aspects (including terminology) related to the use of ultradisperse particulates (nanosystems) are discussed. The important role of nanoparticles in the technology of highly concentrated binding suspensions (HCBS) and refractory castables is emphasized. Using nanoparticles provides a route toward improving the rheotechnologic properties of HCBS and HCBS-based molding mixtures as well as the structure and service properties of the end product. 相似文献