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排序方式: 共有747条查询结果,搜索用时 15 毫秒
1.
Hitoshi Kurokawa Taku Nakayama Yasunori Kobayashi Ken Suzuki Mutsumi Takahashi Seiichi Takami Momoji Kubo Naotsugu Itoh Parasuraman Selvam Akira Miyamoto 《Catalysis Today》2003,82(1-4):233-240
A modified Monte Carlo (MC) simulation was performed to investigate the hydrogen absorption behavior in Pd and Pd–Ag alloys of the composition PdxAg1−x (x=0.7–0.8) under H2 pressure (0.1 MPa) at different temperatures. The present method employed can consider the dissociative adsorption of hydrogen molecule and the subsequent absorption of hydrogen atom by formalizing the relationship between the pressure of hydrogen molecule and hydrogen atom. The potential parameters were determined to reproduce the solution enthalpy of hydrogen in pure metals. The results are in good agreement with experimental findings as well as previous theoretical studies. We confirmed that our method is useful to simulate the absorption of hydrogen in metals and alloys. 相似文献
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The mechanism of the suppression of vapor explosions by adding inversely soluble polymers in water is studied. Vapor explosion experiments and quench experiment are conducted using a silver test piece. Polymetric solution (polyethylene oxide), of concentrations from 0 to 500 wppm, whose normalized viscosity (by water) varies from 1.00 to 2.00, is used. No vapor explosion is observed in the aqueous polymer solution at a concentration higher than 200 wppm. Quench experiments using the silver test piece submerged in the polymer solution and water are performed in order to examine the stability of film boiling. The suppression of the vapor film collapse is attributed to the precipitation of polyethylene as a gel around the vapor film. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(4): 297–306, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10037 相似文献
4.
H Imano H Iso T Tanigawa T Sankai T Ohira M Kudo T Shimamoto S Sato T Okamura M Iida 《Canadian Metallurgical Quarterly》1998,45(6):536-551
To investigate the contribution of the platelet aggregation in the development of cardiovascular diseases, we examined the relation of constitutional and lifestyle variables with platelet aggregation for a total of 306 males aged 50 to 70 in Ikawa town, Akita prefecture (n = 163) and Noichi town, Kochi prefecture (n = 143). The examination of platelet aggregation was completed within 3 hours of obtaining blood samples. We used ADP (Adenosine 5'-diphosphate) as an agonist and obtained PATI (the platelet aggregatory threshold index) by nephelometry. Platelet count, mean platelet volume, white blood cell count, serum fatty acid compositions were also examined and dietary intake of fish, seafood and soy bean foods were inquired using one-week dietary records. PATI indicated a logarithmic normal distribution in both Ikawa and Noichi. The mean of logarithmic transformed PATI (log PATI) was higher in Ikawa than in Noichi. Thus platelet aggregation was lower in Ikawa than in Noichi. According to multiple regression analysis, age, platelet count in platelet rich plasma, mean platelet volume in platelet rich plasma, and white blood cell count were inversely associated with log PATI. Serum arachidonic acid composition tended to be inversely related with log PATI. Serum n3-polyunsaturated fatty acid composition was positively related with log PATI, and log gamma-GTP tended to be positively associated with log PATI. Soy protein intake and cigarette smoking showed no consistent associations with log PATI. This cross-sectional study suggests that serum n3-polyunsaturated fatty acid, and gamma-GTP, as an index of alcohol intake, reduce platelet aggregation while age, white blood cell count, platelet count, mean platelet volume, and serum arachidonic acid raise platelet aggregation. 相似文献
5.
H Kusaba J Kudo T Kuruma R Nagashima M Ra T Mori Y Kaji H Ishibashi Y Niho Y Baba 《Canadian Metallurgical Quarterly》1993,84(6):330-333
Cardiotoxicity of interferon-alpha or gamma, such as fatal arrhythmia and myocardial infarction, has been reported. Therefore cardiotoxicity of interferon should be seriously considered before administration for patients with a pre-existing heart disease. We treated a patient with chronic active hepatitis type B, coexisted with Wolff-Parkinson-White syndrome, who has had frequent attacks of paroxysmal atrial fibrillation. To prevent the occurrence of fatal arrhythmia with an interferon therapy in this patient, we performed radiofrequency catheter ablation of the Kent bundle. After the successful ablation, we could safely administered recombinant interferon alpha-2b for chronic hepatitis type B. 相似文献
6.
在形变温度为1133K、形变速率为2×10~(-3)s~(-1)的试验条件下,采用两段加载拉伸试验方法研究了0.4%C-1.5%Mn钢高温变形后的静态软化行为.调查了由两次加载拉伸变形时的屈服应力求得的静态软化率以及相对峰值应力比和峰值应变比随等温保持时间的变化.详细讨论了动态回复组织和动态再结晶组织对高温变形后的静态软化过程的影响. 相似文献
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Inaba S. Okano K. Matsuda S. Fujiwara M. Hokazono A. Adachi K. Ohuchi K. Suto H. Fukui H. Shimizu T. Mori S. Oguma H. Murakoshi A. Itani T. Iinuma T. Kudo T. Shibata H. Taniguchi S. Takayanagi M. Azuma A. Oyamatsu H. Suguro K. Katsumata Y. Toyoshima Y. Ishiuchi H. 《Electron Devices, IEEE Transactions on》2002,49(12):2263-2270
The 35 nm gate length CMOS devices with oxynitride gate dielectric and Ni salicide have been fabricated to study the feasibility of higher performance operation. Nitrogen concentration in gate oxynitride was optimized to reduce gate current I/sub g/ and to prevent boron penetration in the pFET. The thermal budget in the middle of the line (MOL) process was reduced enough to realize shallower junction depth in the S/D extension regions and to suppress gate poly-Si depletion. Finally, the current drives of 676 /spl mu/A//spl mu/m in nFET and 272 /spl mu/A//spl mu/m in pFET at V/sub dd/=0.85 V (at I/sub off/=100 nA//spl mu/m) were achieved and they are the best values for 35 nm gate length CMOS reported to date. 相似文献
9.
Uchiyama K. Arakawa F. Narita S. Aoki H. Kawasaki I. Matsui S. Yamamoto M. Nakagawa N. Kudo I. 《Micro, IEEE》1993,13(5):12-22
The Gmicro/500, which features a RISC-like dual-pipeline structure for high-speed execution of basic instructions and represents a significant advance for the TRON architecture, is presented. Upwardly-object-compatible with earlier members of the Gmicro series, this microprocessor uses resident dedicated branch buffers to greatly enhance branch instruction execution speed. Its microprograms simultaneously use dual execution blocks to execute high-level language instructions effectively. Fabricated with a 0.6-μm CMOS technology on a 10.9-mm×16-mm die, the chip operates at 50/66 MHz and achieves a processing rate of 100/132 MIPS 相似文献
10.
This paper presents a dynamic compensation concept to grapple with the dynamic defects of a traditional robot arm, especially while performing high-speed endpoint regulations. The proposed high-speed dynamic compensation concept offers a new point of view for cooperating with a traditional manipulator to realize highly dexterous performance of manipulations. The concept is realized through adoption of a high-speed light-weight actuator as well as endpoint closed loop configured high-speed cameras. The dynamic compensation is analyzed experimentally with 1000 Hz visual feedback and a high-speed finger for a robot arm in the case of one degree of freedom. The advantage of the proposed approach is that the modeling for the robot system’s dynamics is not needed, whereas it is necessary and trivial in order to realize high-speed regulations by traditional approaches. Thus, the control issue becomes easier with the proposed approach. As an application for this concept, fast peg-and-hole alignment with large position and attitude uncertainty is studied. The alignment algorithm is based on a visual compliance strategy. Alignment experiments show that with the proposed concept of dynamic compensation as well as visual compliant motion control, robust and fast convergence was realized for most cases. 相似文献