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排序方式: 共有1323条查询结果,搜索用时 15 毫秒
1.
Watanabe H. Komori J. Higashitani K. Sekine M. Koyama H. 《Semiconductor Manufacturing, IEEE Transactions on》1997,10(2):228-232
A novel monitoring method for plasma-charging damage is proposed. This method performs a quick and accurate evaluation using antenna PMOSFET. It was found that not only hot-carrier (HC) lifetime but transistor parameters such as initial gate current and substrate current were changed according to the degree of plasma-charging damage. However, the present work suggests that monitoring the shift of drain current after a few seconds of HC stress is a more accurate method to indicate plasma-charging damage. The monitoring method using the present test structure is demonstrated to be useful for realizing highly reliable devices 相似文献
2.
The copreheat-treatment of non-fusible and slightly fusible coals with A240 and hydrogenated A240 under high temperature-short contact-time conditions around 500 °C has been examined in an attempt to produce a formed coke with better anisotropic development. These conditions shortened the copreheat-treatment time and provided better anisotropic development in the resultant coke after carbonization. Effectiveness of short contact-time has been discussed in terms of the extent of depolymerization of coal molecules suitable for anisotropic development, this being related to coal liquefaction under similar conditions. 相似文献
3.
4.
New technologies such as power electronics have made it possible to change continuously the impedance of a power system not only to control power flow but also to enhance stability. A power system incorporating a variable impedance apparatus such as a variable series capacitor (VSrC) and high-speed phase shifter (HSPS) is called VIPS (Variable Impedance Power System) by the authors. This paper proposes a novel control method of VIPS apparatus such as VSrC and HSPS installed at an interconnecting point for stabilizing inter-area unstable and/or oscillatory modes. The proposed design method of the control system is a kind of hierarchical decentralized control method of a large-scale power system based on a Lyapunov function. Under the proposed control scheme, each subsystem can be stabilized independently by local controllers such as AVR, speed governor and PSS, and then the whole interconnected system can be stabilized by VIPS apparatus taking into account interactions between subsystems. The effectiveness and robustness of the VIPS apparatus control are shown by numerical examples with model systems including a large-scale power system. 相似文献
5.
K Yoshida Y Takamatsu Y Adachi M Kishi H Sekine T Shigematsu 《Canadian Metallurgical Quarterly》1996,37(2):55-62
Endoglucanase production was measured in culture filtrates of four species of Saccobolus growing in media containing glucose or crystalline cellulose as the only carbon sources. Enzyme activity was four to seven times higher in the presence of cellulose than glucose. S. saccoboloides showed maximal growth and enzyme production. The extracellular proteins secreted during growth on cellulose were separated by polyacrylamide gel electrophoresis and stained for proteins. A zymogram technique was used to visualize bands with endoglucanase activity. The four species showed different protein and isoenzyme patterns. 相似文献
6.
D. C. Kim S. Sayama M. Sekine 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(9):1499-1508
Sea clutter was measured using a millimeter wave radar with a frequency of 34.86GHz and pulse length of 30ns. A car carrier ship target was embedded in sea clutter. It has been discovered that target pulse-to-pulse fluctuations obey a Weibull distribution and sea clutter obey a Rayleigh distribution. We obtained target to clutter ratio improvement of 23.8dB by applying the cell average LOG/CFAR techniques. The computer simulation has been made to evaluate the detection probability and the false alarm probability. The simulation result was in good agreement with the observed data. 相似文献
7.
Toshiaki Nishihata Mayumi Ishizaka Sigeharu Yokohama Alice C. Martino Roger E. Gordon 《Drug development and industrial pharmacy》1993,19(20):2679-2698
The effects of particle size and food on the absolute bioavailability of U-78875 in dogs after oral administration of either a suspension or tablet dosage form were investigated. A reduction of particle size caused a significant increase in bioavailability along with an increase in dissolution rate. Additionally, both suspension and tablet dosage forms administered after food caused an increase in bioavailability. Thus, to accelerate drug dissolution, a reduction of U-78875 particle size from the unmilled state is important for the optimization of formulation compositions. To increase the bioavailability of U-78875, postprandial dosing should be considered. 相似文献
8.
In this study, current collecting efficiency of the micro tubular solid oxide fuel cell (SOFC) was estimated to determine optimum size of the micro tubular SOFC. Two models for collecting current from single terminal (ST) and double terminal (DT) of anode tube were proposed and used to calculate the current collecting efficiency as functions of anode thickness, tube length and operating temperature. It was shown that design of the cell geometry and current correcting method are significantly important to achieve high performance micro tubular SOFC stacks. The efficiency loss estimated from the DT model was about 2–4-fold lower than those of obtained from the ST model. The DT model was shown to be more effective for higher operating temperature and the tube length. 相似文献
9.
A superconductor/semimetal/superconductor (S/SM/S) Josephson junction has been developed. We have used an alloy of Pb1–x
Bi
x
(0x 0.6) as the superconductor and Bi as the semimetal. By irradiating at X-band microwave of 10 GHz, Shapiro steps were observed for various bismuth barrier thicknesses inÅ and bismuth weight ratiosx. Finally, we obtained the empirical relationship for barrier thickness, below which microwaves could be detected for various bismuth weight ratiosx at the temperature of 4.2 K. 相似文献
10.
Tomohito Kameda Kazuya Horikoshi Shogo Kumagai Yuko Saito Toshiaki Yoshioka 《中国化学工程学报》2021,28(12):2993-3001
In this paper, we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis. We studied the adsorption of artificial waste dialysate, which is a mixed solution of urea, creatinine, and uric acid, and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical. The amount of adsorption was approximately 1.4 mg·g-1 for urea, 18 mg·g-1 for creatinine, and 20 mg·g-1 for uric acid. The urea, creatinine, and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500℃, and the adsorption capacity of the spherical activated carbon was regenerated. Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process. 相似文献