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941.
Stainless steels of type SUS304 and SUS316 were chemically treated and heated at various temperatures, and the oxide films formed on the surface were analysed by Auger electron spectrometry and conversion electron Mössbauer spectrometry. The outermost oxide layers of stainless steels were enriched with iron and chromium after heat treatment below 600° C and above 700° C, respectively. It was found that at least two magnetic components of iron species were present in the oxide layers of stainless steel heated below 600° C and that the fine particles of iron oxide are produced in the inner oxide layers of the samples prepared by heating at temperatures higher than 700° C. Only paramagnetic iron species were detected in the oxide layers of the stainless steel prepared by chemical treatment. The structures of the oxide layers produced by those heat and chemical treatments are proposed. 相似文献
942.
943.
Mixtures of ZrC-C were chemically vapour deposited from gaseous mixtures of zirconium bromides, methane, hydrogen and argon. The effect of gas composition on the deposition behaviour was studied. The experiments have shown that the methane concentration in the feed gas mixture is a crucial factor in determining the deposition rate and the character of the deposit. Chemical equilibria in the Zr-C-H-Br system were calculated and compared with the experimental results. 相似文献
944.
945.
"Rhesus monkeys in primate chairs were conditioned to bar press within 6 seconds of presentation of a light in order to avoid electric shock. Following acquisition of this avoidance response two animals were placed facing each other and the bar was removed from the chair of one monkey and the stimulus light from the chair of the other. In order for either monkey to avoid shock a communication was necessary since neither animal had access to all elements of the problem. The results indicated that through nonverbal communication of affect an efficient mutual avoidance was performed. It was concluded that this paradigm is an exceptionally efficient and sensitive method for investigations of nonverbal communication." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
946.
947.
Self-aligned aluminium-gate silicon-on sapphire (s.o.s.) m.o.s.f.e.t.s have been fabricated by applying laser-anneal technology from the back surface for activation of the ion-implanted channel layer. The threshold voltage and surface electron mobility were similar to the conventional silicon-gate m.o.s.f.e.t.s, but the low resistivity of gate and interconnection electrodes using aluminium is advantageous for high switching speed m.o.s. l.s.i. 相似文献
948.
The effects of the depositing condition in column fractionation of isotactic polypropylene were studied in detail. A good fractionation was accomplished not only in selective but also in nonselective deposition. Furthermore, it was found, in opposition to Kenyon's opinion, that the polymer was not spread uniformly over the support, but deposited onto the support in the state of particles and that fractionation was not successful in the case of large particles. From these facts, the particle size is regarded as an important factor to attain good fractionation of isotactic polypropylene. 相似文献
949.
This study investigated the occurrence of feedback as a sequential event in both Japanese American and Caucasian American small group discussions. Previous research had indicated that feedback was measurable within a process orientation, and that Japanese cultural variables could affect the occurrence of feedback. The obtained results provided support for the experimental hypothesis that Japanese American groups manifest significantly less feedback behavior than Caucasian American groups when indexed by teams of coder-observers. The concept of “Enryo” and a characteristic Japanese family code of conduct are introduced as possible factors influencing Japanese American communication. 相似文献
950.
Shigemitsu Shin Yuko Hatakeyama Kiyoshi Ogawa Kinya Shimomura 《Materials Research Bulletin》1979,14(1):133-136
A high-temperature form of a brownmillerite-like compound Sr2Fe2O5, which has a perovskite structure with the oxygen vacancies randomly distributed, showed a remarkable NO decomposition at 700–900°C, whereas another brownmillerite-like ferrate (III) of composition Ca2Fe2O5 did not exhibit any significant catalytic activity for NO decomposition over the temperature range from room temperature to 900°C. This difference in their catalytic activities has been explained on the basis of their crystallographic properties, i.e., ordering or disordering of the oxygen deficiencies. 相似文献