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排序方式: 共有675条查询结果,搜索用时 109 毫秒
91.
92.
T. Mamiya H. Kambara S. Kishishita M. Saitoh T. Yoshizumi T. Matsushita S. Inoue 《Journal of Low Temperature Physics》1998,110(1-2):109-114
We observed the excess specific heat (anomaly) other than nuclear origins above 10 mK in bcc solid
3
He of 24.21 cm
3/mole. We checked whether it arises from spin polarons due to vacancies out of equilibrium by applying a strong magnetic field, in which vacancies should diffuse and vanish due to high polarization. The specific heat is the same before and after applying a magnetic field of 10 T. This fact indicates that vacancies did not vanish even in a strong field or the anomaly arises from the origin different from vacancies. 相似文献
93.
94.
Matsushita T. Mihara T. Ikeda H. Hirota M. Hirota Y. 《Electron Devices, IEEE Transactions on》1991,38(7):1576-1581
A novel type of intelligent power device (IPD), which is suitable for automotive monolithic high side switch with high current capability, is presented. An integration of a vertical-power DMOSFET and planar MOS IC devices is performed by the newly developed junction-isolation technique using only one epitaxial growth. The isolation voltage of 80 V has been obtained, which is large enough for automotive IPDs if they are protected against high voltage transients on the battery line. A rugged vertical DMOSFET (VDMOS) has also been developed for this IPD. It has a cellular Zener diode between its source and drain, which prevents the secondary breakdown of parasitic bipolar transistor, and the resulting avalanche capability enhancement is more than an order of magnitude. This VDMOS is used for both output power device and protection device for low-voltage MOS circuitry, which makes the IPD free from any transients in the automobile without the need for external protection 相似文献
95.
96.
97.
A colorimetric microassay is described for the determination of lipid hydroperoxides. Hydroperoxides are reacted with potassium
iodide in the presence of an acid catalyst and liberated iodine is measured. Aluminum chloride, an alcohol-soluble Lewis acid,
is used as catalyst. Liberated iodine is measured colorimetrically at 560 nm after addition of starch in 0.01 N hydrochloric
acid. The range of the measurement was 0.05–0.5 μmol of hydroperoxides. 相似文献
98.
S Murata K Iwahashi T Yasunaga T Hasegawa S Matsushita 《Canadian Metallurgical Quarterly》1976,11(2):227-239
The authors have infected 127 B. glabrata by 2 miracidia of S. mansoni, either on the Same day, or introducing a second miracidium after 3, 7 and 16 days. 1 All the groups of planorbid snails had a low percentage of positivity (31 to 41 %). 2 The first cercarial emissions, in the 4 groups were scattered in the time, the delay being in correlation with the second infection. 3 In the snails reinfected after 3 and 7 days occured the highest emissions, those with the simultaneous double infection or second infection delayed to 16 days, had the lesser emissions. 4 An interval cycle of about 3 weeks was discovered for the highest emissions. All those phenomena are probably due to competition between the sporocysts born from both miracidia. Moreover, evident reduction of the fecundity in the positive snails were shown only after the beginning of the cercarial emissions, while a normal, or even increased fecundity was established in the prepatent period of the infected snails. 相似文献
99.
100.
This paper shows that optimal preview control system approaches to a decoupled preview control system as the weighting factors for the control input variables in the quadratic performance index tend towards zero. Therefore, to examine the characteristics of the decoupled preview control system also means to examine the asymptotic characteristics of the optimal preview control system. By this property, relationships between the design parameters and the response of the optimal preview control system become clear and the design of the optimal preview control can be simplified by utilizing the properties that the decoupled preview control system features. Further, the decoupled preview control method is applied to the vector control system for an induction motor drive. By this application, a trade off between the conditions of the vector control and the magnitude of input variables becomes easy. To demonstrate the significance of this proposed method, simulation results of this application are carried out 相似文献