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排序方式: 共有409条查询结果,搜索用时 15 毫秒
51.
Transport current and n-value of DyBCO-coated conductor pulled in tension were measured experimentally and their relation to crack-induced current shunting was analyzed with the partial crack-current shunting model. The following features were revealed. The shunting current increases with increasing transport current and with increasing crack size. At low voltage where shunting current is low, the transport current of cracked sample normalized with respect to the transport current in non-cracked state is described with the modified ratio of non-cracked area to overall cross-sectional area of superconducting layer. At high voltage where the shunting current is high, the normalized transport current becomes higher than the modified ratio of non-cracked area. The increase in shunting current with transport current (and voltage) leads to a decrease in n-value at high current (voltage). This phenomenon is enhanced by crack extension. 相似文献
52.
M Maruyama T Kudo H Kuwahara S Takamatsu N Sugano M Ebuchi 《Canadian Metallurgical Quarterly》1997,24(13):2011-2014
A 28-year-old female underwent sigmoidectomy for sigmoid colon cancer with peritoneal seeding. One month later, a solitary metastasis was found in S3 of the liver. After CDDP/5-FU intravenous chemotherapy, another metastasis appeared in S7. Intravenous administration showed PD. But the metastatic tumors shrank and became inobservable by CT after the 1st round of CDDP/5-FU intraperitoneal chemotherapy, and S7 tumor could not be identified after the 2nd round. Many previous reports demonstrated the concentration of cytotoxic drug in intraperitoneal administration was much higher than in intravenous administration. Theoretically, intraperitoneal chemotherapy is superior to intravenous chemotherapy for the prevention and treatment of liver metastases. This case demonstrated this hypothesis was right. We think adjuvant intraperitoneal chemotherapy should be re-considered for the prevention of the liver metastases of gastrointestinal cancers. 相似文献
53.
JY Gu Y Wakizono A Dohi M Nonaka M Sugano K Yamada 《Canadian Metallurgical Quarterly》1998,62(10):1917-1924
We examined the effect of three dietary fats, safflower oil (SAF) rich in linoleic acid, borage oil (BOR) rich in gamma-linolenic acid, and perilla oil (PER) rich in alpha-linolenic acid, on the lipid metabolism, and chemical mediator and immunoglobulin levels in Sprague-Dawley rats, as well as the dietary effect of sesame-derived antioxidative sesamin. The serum cholesterol, phospholipid, triglyceride, prostaglandin E2 level and splenic leukotriene B4 level were lower in the rats fed on BOR or PER than in those fed on SAF. SES feeding suppressed the expression of the lipid-decreasing effect of BOR, but not in the rats fed on PER. In respect of the fatty acid composition of the liver and spleen, PER feeding gave a lower arachidonic acid level, and higher eicosapentaenoic and docosahexaenoic acid levels than SAF feeding did, while the effect of BOR feeding was marginal. The effect of SES feeding on fatty acid composition was much smaller than that of dietary fats. In respect of immunoglobulin production, PER + SES feeding gave the lowest IgE productivity in the mesenteric lymph node lymphocytes. These results suggest that PER feeding regulated lipid metabolism and exerted an anti-allergic effect by a different mechanism from that with BOR feeding. 相似文献
54.
Local damage to reinforced concrete structures caused by impact of aircraft engine missiles Part 1. Test program, method and results 总被引:3,自引:0,他引:3
T. Sugano H. Tsubota Y. Kasai N. Koshika H. Ohnuma W.A. von Riesemann D.C. Bickel M.B. Parks 《Nuclear Engineering and Design》1993,140(3):387-405
Structural damage induced by an aircraft crashing into a reinforced concrete structure includes local damage caused by the deformable engines, and global damage caused by the entire aircraft. Local damage to the target may consist of spalling of concrete from its front face together with missile penetration into it, scabbing of concrete from its rear face, and perforation of missile through it. Until now, local damage to concrete structures has been mainly evaluated by rigid missile impact tests. Past research work regarding local damage caused by impact of deformable missiles has been limited. This paper presents the results of a series of impact tests of small-, intermediate-, and full-scale engine models into reinforced concrete panels. The purpose of the tests was to determine the local damage to a reinforced concrete structure caused by the impact of a deformable aircraft engine. 相似文献
55.
Children with cerebral palsy (CP) display postural problems, largely interfering with daily life activities. Clarification of neural mechanisms controlling posture in these children could serve as a base for more successful intervention. Studies on postural adjustments following horizontal forward and backward displacements of a movable platform in ten school-age children with spastic diplegia and non-disabled controls revealed that sitting CP children, like standing CP children, show direction specific postural adjustments, indicating that the basic pattern of muscle coordination in these conditions is conserved. Dysfunctions are especially present in the modulation of the response pattern of ventral muscles during forward translations. They consist of: (1) a stereotyped and non-variable activation of all ventral muscles; (2) an abnormal top-down muscle recruitment; and (3) an excessive degree of antagonistic co-activation. The altered patterns of muscle coordination could be the result of two interacting mechanisms, the primary deficit due to the early brain damage and a compensation due to the postural instability. Especially the latter dysfunction furnishes opportunities for therapeutic help. 相似文献
56.
The vortex core in chiral p-wave superconductors exhibits various properties owing to the interplay between the vorticity and chirality inside the vortex core. In the chiral p-wave superconductors, the site-selective nuclear spin-lattice relaxation rate T
–1
1 is theoretically studied inside the vortex core within the framework of the quasiclassical theory of superconductivity. T
–1
1 at the vortex center depends on the sense of the chirality relative to the sense of the magnetic field. The effect of a tilt of the magnetic field upon T
–1
1 is investigated. The effect of the anisotropy in the superconducting gap and the Fermi surface is then investigated. The result is expected to be experimentally observed as a sign of the chiral pairing state in a superconducting material Sr2RuO4. 相似文献
57.
T. Hanajiri K. Aoto T. Hoshino M. Niizato Y. Nakajima T. Toyabe T. Morikawa T. Sugano Y. Akagi 《Computational Materials Science》2004,30(3-4):235-241
A quantum mechanical (QM) approach for modeling and simulation of MOS devices, covering the whole operation region, was proposed. This formulation is applicable continuously from the subthreshold to the saturation regions, since it exactly treats the QM effects on the in-depth distribution of the gate induced carriers in the channel by solving one dimensional Poisson equation and Schrödinger equation self-consistently and it treats the lateral drift–diffusion transport using quasi-Fermi potential. A QM simulator was implemented using this QM approach. This QM simulator was verified by classical three-dimensional device simulator, CADDETH, in the whole range of operation of bulk MOSFET with low dopant density where QM effect is negligible. The QM simulation elucidated that the threshold voltage shift in thin SOI MOSFETs in saturation region as well as in linear region results from energy shift of the lowest conduction electron level and effective increase of gate oxide thickness. 相似文献
58.
Shimoda M. Sugano A. Kimura T. Watanabe Y. Ishiyama K. 《Energy Conversion, IEEE Transaction on》1990,5(4):640-645
A method for predicting unburnt carbon in a coal-fired utility boiler has been developed using an image processing technique. The method consists of an image processing unit and a furnace model unit. The temperature distribution of combustion flames can be obtained through the former unit. The latter calculates dynamics of the carbon reduction from the burner stages to the furnace outlet using coal feed rate, air flow rate, and the chemical and ash content of the coal. An experimental study in the Sendai Power Station of Tohoku Electric Company Inc. shows that the prediction error of the unburnt carbon can be reduced to 10%. The results show that the unburnt carbon prediction algorithm could be widely used for evaluation, optimization and diagnosis of combustion systems for various boiler and coal types 相似文献
59.
60.