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991.
M. Glyavin V. Zapevalov T. Idehara I. Ogawa 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(4):409-418
Influence of power supply voltage instability on gyrotron operation regime is investigated. Dependence of efficiency versus variations of external parameters is given and conditions of oscillations cutoff are determined. It is shown that positive voltage fluctuations result in sharp falling efficiency and failure of self-oscillations and the steadiest gyrotrons are those with short cavities and the large ratio of transverse electron speed to longitudinal one around 1.5 - 2. Comparison of theoretical and experimental results is given. 相似文献
992.
I. Ogawa K. Yamada T. Idehara A. Tsushima S. Yamaguchi 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(5):651-660
Carrier properties of n-type InSb doped with tellurium at liquid nitrogen temperature have been estimated by means of transmission of a millimeter wave (119.3 GHz) propagating along a magnetic field with intensity up to 4 T. The information on carrier properties is obtained from the Faraday rotation arising from the difference between phase velocities of two circularly polarized components. The advantage of this method lies in the fact that it allows both the electron density and effective mass to be measured simultaneously. 相似文献
993.
M Amano A Togawa S Tsurugano Y Soda A Yuo F Takaku S Ogawa H Hirai K Yamada 《Canadian Metallurgical Quarterly》1993,81(9):2469-2470
994.
T Sugimoto K Ogawa T Asada N Mukohara T Higami H Obo 《Canadian Metallurgical Quarterly》1993,41(9):1528-1534
We experienced 4 cases of left coronary artery-pulmonary artery fistula. Two cases had small fistulas associated with atherosclerotic coronary lesions, and the other 2 had large fistulas with aneurysmal enlargement. In the former 2 cases, ligation of the fistulas and closure of the opening of fistula into the pulmonary artery through pulmonary arteriotomy were performed together with coronary artery bypass grafting and left ventricular aneurysmectomy. In one of the latter 2 cases, the fistula arising from the anterior descending branch was ligated and the opening of fistula draining into the pulmonary artery was closed through pulmonary arteriotomy. In another case, both openings of the fistula into the anterior descending branch and the pulmonary artery were closed from inside through incision of the dilated fistula. In all 4 cases, operations were performed using cardiopulmonary bypass and retrograde coronary perfusion, which could afford good heart protection even in cases with coronary lesions and coronary steal phenomenon. All cases went an uneventful postoperative course. Postoperative angiograms showed disappearance of the fistulas in 3 cases. In one case, however, residual fistula was found because a fine fistula might be overlooked. In such a case with complicated fistulas with aneurysmal enlargement, fistulas should be examined carefully through incision of the enlarged anomalous vessels. In this paper, diagnosis, operative indication and treatment for coronary artery-pulmonary artery fistula were discussed. 相似文献
995.
996.
DA Poncelet EJ Bellefroid PV Bastiaens MA Demoitié JC Marine H Pendeville Y Alami N Devos P Lecocq T Ogawa M Muller JA Martial 《Canadian Metallurgical Quarterly》1998,17(11):931-943
We previously identified the ZNF85 (HPF4) KRAB zinc finger gene, a member of the human ZNF91 family. Here, we show that the ZNF85 gene is highly expressed in normal adult testis, in seminomas, and in the NT2/D1 teratocarcinoma cell line. Immunocytochemical localization of a panel of beta-Gal/ZNF85 fusion proteins revealed that ZNF85 contains at least one nuclear localization signal located in the spacer region connecting the KRAB domain with the zinc finger repeats. Bacterially expressed ZNF85 zinc finger domain bound strongly and exclusively to DNA in vitro in a zinc-dependent manner. The KRAB(A) domain of the ZNF85 protein and of several other members of the ZNF91 family exhibited repressing activity when tested in Gal4 fusion protein assays. The repression was significantly enhanced by the addition of the KRAB (B) domain, whereas further addition of other conserved regions had no effect. The ZNF85 KRAB(A) and (B) domains in vitro bound several nuclear proteins that might constitute critical cofactors for repression. 相似文献
997.
3,3'-Dihydroxy-alpha,beta-diethyldiphenylethane (I), 3,3'-dihydroxy-alpha,beta-diethylstilbene (II), hexestrol (III) and diethylstilbestrol (IV) have already been reported to show hypotensive effects on rats and exhibit phytogrowth-inhibitory activities. We have proposed that two phenolic hydroxyl groups in these compounds are necessary for the biological activities, and a structure-activity relationship for I-related compounds was accomplished using molecular-mechanics (MM) calculations. As a result, the following three findings were obtained; 1) the minimized conformational energy obtained from MM calculations, which is a parameter expressing the molecular stability, showed a relatively high correlation with the biological activities, 2) as results of quantitative structure-activity relationship (QSAR) analyses, the combination of the distance between two phenolic hydroxyl oxygens led to the regression equations with high correlation values, and 3) the idealized molecular model of the most active compound (I) showed the highest stability and had a particular conformation which differed from the other compounds (II-IV). 相似文献
998.
The paper discusses how computers can assist human creativity. A support system has been built and applied to the domain of automobile design. The system uses multidimensional data and statistical methods, and configures a space for inspiring the users' design activity. In the first step, it assists them in forming individual design concepts. In the second step, it assists them in deciding their target design concepts. It has been confirmed that it works effectively through experiments. Some of the open questions on creativity support systems are also discussed. 相似文献
999.
This paper presents a Fortran program to calculate cross sections for various reactions between composite particles in the framework of Glauber theory. The projectile nucleus is described as a core plus one valence-nucleon system. The input data needed for the calculation are the core and target densities and the nucleon-nucleon profile function. The single-particle wave function of the valence nucleon may be provided by a user or generated by the code if appropriate quantum numbers of the wave function are specified. Multiple integrations involving the valence-nucleon wave function are performed by a Monte Carlo technique with Metropolis algorithm. The program gives the total reaction cross section, the one-nucleon removal cross section, the elastic differential cross section, and the longitudinal momentum distribution of the core fragment. Sample calculations include the reactions of 13,19C+12C, 11Be+12C, 11Be+9Be, and 8B+12C systems. 相似文献
1000.
A practical design procedure for a circularly polarized printed array antenna composed of strip dipoles and slots (CP-PASS) is presented. CP-PASS is a kind of series-fed array, and the equivalent circuit model of CP-PASS is simplified to be suitable for a computer-aided design (CAD) package. Some experimental results of a new strip element excited by a stripline and a 9-element set CP-PASS are also presented. 相似文献