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981.
A network of powerful personal computers, linked by a high-speed local area network, is being seen increasingly as an alternative to a traditional centralized time-sharing operating system. The PULSE project is investigating how such a system may be constructed to give the benefits of a self-sufficient personal computer to each user without losing the facilities for communication and sharing of data inherent in centralized systems. In particular, a distributed file system has been built which provides a single global UNIX 1 UNIX is a trademark of Bell Laboratories. -like hierarchy, with a consistent appearance when accessed from any machine. Replicated copies of files are maintained to improve reliability, increase performance, and enable each machine to run stand-alone, albeit with reduced facilities. 相似文献
982.
I. M. Tang 《Journal of Low Temperature Physics》1985,60(3-4):265-275
The thermal conductivity coefficient for a Kondo superconductor in the gapless state is obtained within the framework of the Matsuura, Ichinose, and Nagaoka theory. By expanding the heat current correlation function appearing in the Kubo formula for the thermal conductivity in powers of the order parameter, analytical expressions for the thermal conductivity to second power in the order parameter are obtained. The thermal conductivities for bothT
KT
c
0 andT
KT
c
0 superconductors are obtained. 相似文献
983.
Conclusions Alloying of Nichrome with molybdenum significantly strengthens it as the result of the formation of a solid solution of molybdenum in nickel and the formation in the structure of inclusions of a very hard phase, molybdenum carbide.Heat treatment of the Nichrome-base material by normalizing and then aging strengthens it significantly as the result of formation of dispersed high hardness -phase.The high strength properties of the material hardened by high hardness molybdenum carbide and -phase are stable in the 0–700°C temperature range. A further increase in test temperature (above the hardening heat-treatment temperature) sharply reduces its strength characteristics.Translated from Poroshkovaya Metallurgiya, No. 4(268), pp. 75–78, April, 1985. 相似文献
984.
985.
Yu. M. Lakhtin G. N. Neustroev N. I. Sologubova L. P. Frolova 《Metal Science and Heat Treatment》1987,29(5):359-364
Conclusion Carbonitriding at 700°C in a mixture of 70–30% of ammonia and 30–70% of endogas (or natural gas) is recommended for the production of a diffusion layer with a good set of operational properties (for example, with high wear resistance).Moreover, the use of a gaseous atmosphere based on commercial nitrogen (50–90%) with ammonia, natural-gas, oxygen, or carbon dioxide additives is promising for carbonitriding at 700°C. Here, this medium should not contain more 0.5–1.0% of O2 and 3% of CO2. The nitrogen-based gaseous atmospheres ensure the attainment of quality diffusion layers with decreased risk of explosion and saving of energy resources.Moscow Automobile Traffic and Highway Construction Institute. Nongovernmental Production Union "All-Union Scientific-Research and Experimental Design Institute for Trade Machine Construction. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 5, pp. 32–36, May, 1987. 相似文献
986.
"Inpitan" is the first Soviet full-value balanced food mixture for tube feeding, produced under industrial conditions. It was used for enteral nutrition of 50 patients with different diseases of the upper gastro-intestinal tract. The mixture contains protein (12%), fat (30%), carbohydrates (58%), all the necessary mineral substances, and water- and fat-soluble vitamins. Depending on the clinical situation the patients received 2000-3200 ml of the mixture/day. The use of "Inpitan" with the energy density of 1 kcal/ml as the only source of nutrition during 7-75 days has demonstrated its high nutritious effectiveness. When the mixture was introduced directly into the small intestine according to the authors' schedule, no dyspeptic symptoms (eructation, nausea, vomiting, abdominal pain, meteorism, diarrhea) were recorded, dipsosis and the sense of starvation disappeared, the body weight increased, biochemical parameters returned to normal, the time of the preoperational preparation was significantly reduced, the post-operational complications were better managed. 相似文献
987.
The creep and recovery behaviour of highly drawn polypropylene monofilaments has been studied over the temperature range 20 to 50° C. A range of samples was examined to identify the influence of draw ratio and molecular weight. It is concluded that the permanent flow creep arises from the presence of two thermally activated processes, one of which relates to the -relaxation process and is associated with the crystalline regions of the polymer, and the second with the molecular network. 相似文献
988.
989.
990.
The paper reports on an investigation of the electric resistance as a function of temperatureT, magnetic fieldH, and applied voltageV in granular indium films when approaching the metal-insulator transition (MIT) due to increased thickness of the oxide layers between granules. The dependences are shown to be governed atT5 K by competition of the hopping conductivity and the Josephson tunneling of electrons, sometimes giving rise to a resistance minimum inR(T) associated with superconductivity. It was also found that even when the intergranular Josephson tunneling is totally suppressed, transition of granules to the superconducting state influences essentially the dependencesR(T, H), changing the functional form ofR(T) and resulting in anomalously high negative magnetoresistance. This is shown to stem from the change of the character of activated electron tunneling as the granules become superconducting. 相似文献