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排序方式: 共有1082条查询结果,搜索用时 15 毫秒
961.
962.
Y Hiramoto M Onda A Tokunaga T Shirakawa K Ikeda M Takita T Teramoto I Fujita T Okuda T Kiyama T Yoshiyuki H Hasegawa S Kato M Miyashita N Matsukura Y Sugisaki 《Canadian Metallurgical Quarterly》1998,25(9):1284-1287
Examinations of peritoneal lavage smears (cy) in gastric cancer surgical stages III and IV are very important for determining the disease stage. We have been carrying out these examinations for 8 years. One hundred sixty patients with gastric cancer were examined. The incidence of cy positivity was higher in T4 than in T3, and higher in P1,2,3 than in P0. We performed intraperitoneal administration of CDDP in 10 patients with gastric cancer using a reservoir (Infuse-A-Port) implanted in the abdominal wall once a week. No difference in survival was observed between patients who received chemotherapy via i.p. and those who received it i.v. 相似文献
963.
964.
Effect of decreased hot-rolling reduction treatment on fracture toughness of low-alloy structural steels 总被引:2,自引:0,他引:2
Yoshiyuki Tomita 《Metallurgical and Materials Transactions A》1990,21(9):2555-2563
Commercial low-alloy structural steels, 0.45 pct C (AISI 1045 grade), 0.40 pct C-Cr-Mo (AISI 4140 grade), and 0.40 pct C-Ni-Cr-Mo
(AISI 4340 grade), have been studied to determine the effect of the decreased hot-rolling reduction treatment (DHRRT) from
98 to 80 pct on fracture toughness of quenched and highly tempered low-alloy structural steels. The significant conclusions
are as follows: (1) the sulfide inclusions were modified through the DHRRT from a stringer (mean aspect ratio: 16.5 to 17.6)
to an ellipse (mean aspect ratio: 3.8 to 4.5), independent of the steels studied; (2) the DHRRT significantly improvedJ
Ic
in the long-transverse and shorttransverse orientations, independent of the steels studied; and (3) the shelf energy in the
Charpy V-notch impact test is also greatly improved by the DHRRT, independent of testing orientation and steels studied; however,
(4) the ductile-to-brittle transition temperature was only slightly affected by the DHRRT. The beneficial effect on theJ
Ic
is briefly discussed in terms of a crack extension model involving the formation of voids at the inclusion sites and their
growth and eventual linking up through the rupture of the intervening ligaments by local shear. 相似文献
965.
Miou Furuya Yoshiyuki Kawazoe Kaoru Ohno 《Science and Technology of Advanced Materials》2004,5(5-6):689
The crystal made of organic radical, 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA), exhibits a large first-order magnetic and structural phase transition between a paramagnetic high-temperature (HT) phase and a diamagnetic low-temperature (LT) phase, with a surprisingly wide thermal hysteresis loop over room temperature. We investigate theoretically the crystal structures for the two phases by means of the ab initio structural optimization method based on the local density approximation. We present necessary and sufficient atomic coordinates in this paper. The resulting structures are in good agreement with the recent X-ray diffraction experiment. In the HT phase, uniform one-dimensional stacking of the radical molecule appears, while, in the LT phase, strong dimerization along the stacking direction appears. 相似文献
966.
967.
Classification of handprinted Kanji characters by the structured segment matching method 总被引:1,自引:0,他引:1
Yoshiyuki Yamashita Koichi Higuchi Youichi Yamada Yunosuke Haga 《Pattern recognition letters》1983,1(5-6):475-479
A method for handprinted Kanji character classificatin is proposed in this paper. After extraction of directional line segments and partitioning of the character frame area, a feature vector that represents the distribution of strokes is generated and is matched with average vectors in a dictionary. 相似文献
968.
Yanna Guo Teahoon Park Jin Woo Yi Joel Henzie Jeonghun Kim Zhongli Wang Bo Jiang Yoshio Bando Yoshiyuki Sugahara Jing Tang Yusuke Yamauchi 《Advanced materials (Deerfield Beach, Fla.)》2019,31(17)
Heterogenous electrocatalysts based on transition metal sulfides (TMS) are being actively explored in renewable energy research because nanostructured forms support high intrinsic activities for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, it is described how researchers are working to improve the performance of TMS‐based materials by manipulating their internal and external nanoarchitectures. A general introduction to the water‐splitting reaction is initially provided to explain the most important parameters in accessing the catalytic performance of nanomaterials catalysts. Later, the general synthetic methods used to prepare TMS‐based materials are explained in order to delve into the various strategies being used to achieve higher electrocatalytic performance in the HER. Complementary strategies can be used to increase the OER performance of TMS, resulting in bifunctional water‐splitting electrocatalysts for both the HER and the OER. Finally, the current challenges and future opportunities of TMS materials in the context of water splitting are summarized. The aim herein is to provide insights gathered in the process of studying TMS, and describe valuable guidelines for engineering other kinds of nanomaterial catalysts for energy conversion and storage technologies. 相似文献
969.
Kizuku Kushimoto Mika Moriyama Atsuko Shimosaka Yoshiyuki Shirakawa Jusuke Hidaka Shingo Ishihara Junya Kano 《Advanced Powder Technology》2021,32(1):272-282
A new model for estimating macroscopic permittivity was proposed to predict filler particles' dispersion states in a particulate composite material. In the model, the estimation targets are randomly packed composite materials. The composite materials were represented as a cluster of unit cells. A proposed layer structure model connected the unit cells. The macroscopic permittivity was estimated by calculating the synthetic capacity of the cluster. The proposed model was validated by comparisons between estimated and measured macroscopic permittivity of several particulate composite materials. It was also identified that the proposed model could estimate the permittivity more accurately than an existing theoretical equation's one due to considering the effects for the dispersion states of filler particles. Furthermore, it was indicated that the proposed model could also estimate the dispersion states of filler particles by the measured permittivity. The applicability of the method was confirmed by comparisons between estimated and experimental dispersion states of filler particles. 相似文献
970.
Hide‐aki Nishikawa Yoshiyuki Furuya Satoshi Igi Sota Goto Fabien Briffod Takayuki Shiraiwa Manabu Enoki Tadashi Kasuya 《Fatigue & Fracture of Engineering Materials & Structures》2020,43(6):1239-1249
To clarify the effect of microstructural changes on the fatigue property of the weld heat‐affected zone (HAZ), low‐ to high‐cycle fatigue tests were conducted on 16 types of simulated HAZ specimens that had been prepared using thermal processes. The results showed the fatigue S‐N curves of the HAZ to be widely scattered as a function of strength level. These fatigue data were divided into two groups: coarse grain (CG) and fine grain (FG) HAZ, when strain amplitude was used to represent S‐N curves. The fatigue data for the CGHAZ group showed a relatively short fatigue life. Based on surface observations, the initiated fatigue crack size of CGHAZ was larger than that of FGHAZ as a function of microstructural unit size. Hence, fatigue crack growth life, which is almost the same as total fatigue life of CGHAZ, decreased. 相似文献