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761.
Kikuchi H Watanabe T Kasama K Wakui C Matsuki A Akiyama H Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(1):21-27
To investigate important factors affecting the reliability of the analytical results, proficiency tests were attempted for the histochemical method (GUS method) and the qualitative PCR method (PCR method) to detect genetically modified papaya (55-1) in the Japanease official method. The test samples were distributed to twenty-three laboratories that participated in the study and were examined according to the protocol. All the data collected from participating laboratories were statistically analyzed. In the PCR method, one negative sample was detected as positive using detection primers in one laboratory, though the sample was negative when checked using confirmation primers. Contamination might have occurred in the step of the preparation of the PCR sample solution using detection primers. In the GUS method, all the test samples were identified as expected. Thus, all the laboratories reported correct results overall. 相似文献
762.
T. Ohtsuka M. Akiyama T. Saito Y. Ishizaki A. Suzuki N. Negishi J. Moriya K. Hoashi T. Hoshino 《International Journal of Hydrogen Energy》1982,7(6):455-462
An assessment is made of hydrogen technology development; in particular, economy as an energy carrier, applicability for end-uses and the potential of the market in the future. Specifically, rough static cost comparisons are made on several modes of electricity transmission and hydrogen transport, and on several ways of off-peak electricity saving; including energy storage in the form of hydrogen. Then, the quantity of oil that could be saved for some representative end-use sectors if hydrogen fuel were to be introduced is discussed. Finally, a potential market is assessed, by projecting overall future energy supply/demand dynamics in Japan. 相似文献
763.
Phase equilibria have been established in the binary system Gd2O3MoO3 including Gd2(MoO4)3 with ferroelectricity and ferroelasticity below 159°C, by means of differential thermal analysis and X-ray powder diffraction techniques. It is shown that Gd2(MoO4)3 has no solubility of other compounds in this system and melts congruently on its stoichiometric composition. Three distinct intermediate compounds were found. Gd2O3.6MoO3 and Gd2O3.4MoO3 are formed by a peritectic reaction at 730°C and 825°C, respectively. The remaining compound Gd2O3.MoO3 with the structure closely related to Eu2O3.MoO3 does not decompose below 1400°C. 相似文献
764.
Xinfeng Li Xianfeng Ma Jin Zhang Eiji Akiyama Yanfei Wang Xiaolong Song 《金属学报(英文版)》2020,33(6):759-773
Hydrogen dissolved in metals as a result of internal and external hydrogen can affect the mechanical properties of the metals, principally through the interactions between hydrogen and material defects. Multiple phenomena such as hydrogen dissolution, hydrogen diffusion, hydrogen redistribution and hydrogen interactions with vacancies, dislocations, grain boundaries and other phase interfaces are involved in this process. Consequently, several hydrogen embrittlement(HE) mechanisms have been successively proposed to explain the HE phenomena, with the hydrogen-enhanced decohesion mechanism, hydrogenenhanced localized plasticity mechanism and hydrogen-enhanced strain-induced vacancies being some of the most important. Additionally, to reduce the risk of HE for engineering structural materials in service, surface treatments and microstructural optimization of the alloys have been suggested. In this review, we report on the progress of the studies on HE in metals, with a particular focus on steels. It focuses on four aspects:(1) hydrogen diffusion behavior;(2) hydrogen characterization methods;(3) HE mechanisms; and(4) the prevention of HE. The strengths and weaknesses of the current HE mechanisms and HE prevention methods are discussed, and specific research directions for further investigation of fundamental HE mechanisms and methods for preventing HE failure are identified. 相似文献