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91.
Yamagishi Shigeru 《Journal of Nuclear Materials》1975,57(1):56-68
The knock-out release of fission products is studied theoretically. The general equations of knock-out release are derived, assuming that a fission fragment passing through the surface of nuclear fuels knocks out a local region of the surface with an effective thickness and an effective cross-sectional area. Using these equations, the knock-out release of fission gases is calculated for various cases. The conditions under which the knock-out coefficients (the average number of uranium atoms knocked out by one fission fragment) is obtainable are clarified by experiments on the knock-out release of fission gases. A method of determining the effective thickness and the effective cross-sectional area of a knock-out region is proposed. 相似文献
92.
93.
94.
95.
Koichi Hatada Tatsuki Kitayama Shigeru Danjo Yutaka Tsubokura Heimei Yuki Kazuyuki Moriwaki Hiroaki Aritome Susumu Namba 《Polymer Bulletin》1983,10(1-2):45-50
Summary Polymer of α-substituted benzyl methacrylate was found to be used as a new type of positive electron-beam resist, which forms
methacrylic acid units in the polymer chain on the exposure to electron-beam and can be developed using alkaline solution
as a developer. The sensitivity was dependent on the bulkiness of the ester group and the number of ?-hydrogen atoms in the
ester group. The sensitivity and γ-value of atactic poly(α, α-dimethylbenzyl methacrylate) were improved by a factor of more
than three over poly (methyl methacrylate). 相似文献
96.
We summarize the reliability growth models for hardware and software systems described by a stochastic process, where the underlying stochastic process is assumed to be a nonhomogeneous Poisson process (NHPP). The background of reliability growth modelling based on an NHPP is surveyed. The Duane model, which was first postulated as a reliability growth model and is commonly used, is first explained. Secondly, the Weibull growth and modified Weibull growth models for hardware systems and the exponential type growth and gamma type growth models for error detection for software systems are discussed. The parameter estimates can be obtained by maximum likelihood estimation. Finally, the goodness-of-fit tests based on chi-square, Cramér-von Mises and Kolmogorov-Smirnov statistics are presented for the reliability growth models based on an NHPP. 相似文献
97.
98.
The purpose of this paper is to study the filtering problems from the viewpoint of the information theory. For a linear system it is proved that the necessary and sufficient condition for maximizing the mutual information between a state and the estimate is to minimize the entropy of the estimation error. Then we derive the Kalman-Bucy filter for both the discrete-time and the continuous-time systems by an application of the information theory. Furthermore, the approach is extended to the nonlinear dynamical systems with noisy observations and then the information structures of the optimal filter for a continuous-time nonlinear system are made clear, which has been presented as the interesting open problems by Bucy. 相似文献
99.
Shigeru Imai Satoru Takagi Toshio Iizuka Osamu Sugiura Masakiyo Matsumura 《Materials and Manufacturing Processes》1995,10(2):267-281
Two methods are proposed and demonstrated successfully for low temperature atomic layer epitaxy (ALE) of Si, where H atoms play essential roles. The first method is the use of H as a self-limiting factor. Trisilane (Si3H8) was used as source gas and the substrate temperature was modulated in order to alternate steps in an ALE cycle. When the temperature was less than 380°C in the adsorption step and more than 520°C in the desorption step, respectively, the grown layer thickness per cycle was 0.8 ML/cycle. The second method is the use of atomic H as an active reducer of a self-limiting factor. A clean surface was exposed to dichlorosilane (SiH2Cl2) as source gas to grow an Si monolayer covered with CI. Next, atomic H was injected to reduce CI from the surface. An ideal monolayer growth was obtained with the substrate temperature over 540°C. 相似文献
100.
Haruo Yoshimura Yoshihisa Endo Shigeru Hashimoto 《Journal of the American Oil Chemists' Society》1991,68(8):623-628
Terminal olefins can be converted into the corresponding sulfonates by sulfonation with SO3 followed by hydrolysis, the products are used as detergent ingredients. Although internal olefins were also expected to be
good feed stocks, it was difficult to convert them into the corresponding sulfonates with as good of a yield as that of terminal
olefins under the same synthesis conditions.
Our studies have been carried out in order to clarify the reason for poorer conversion of the internal olefins. It was found
by a nuclear magnetic resonance spectroscopic study that the major components of the sulfonated intermediate of internal olefins
wereβ-sultones, the amounts of which were usually very small in sulfonated terminal olefins. A portion of theseβ-sultones was desulfonated, depending on temperature, to the original olefins and the corresponding sulfate salts during alkaline
hydrolysis. The prevention of desulfonation of theβ-sultones in the hydrolysis process was one of the most important aspects for the production of internal olefin sulfonates.
Finally, by keeping the hydrolysis temperature below 35°C, the conversion of internal olefins into sulfonates was achieved
with the same yield as that of conventional terminal olefins. 相似文献