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排序方式: 共有1017条查询结果,搜索用时 15 毫秒
1.
The synthesis of thermal-shock-resistant materials from the system Ta2O5WO3 was investigated. Ta2WO8 had a very low unit-cell thermal expansion coefficient (+0.5 X 10–6° C–1). Ta30W2O81 also had a relatively low coefficient (+4.0 X 10–6 ° C–1) and a thermal durability over 1600° C. The thermal expansion curves of these polycrystalline ceramics were lowered because of microcracks caused by the large thermal expansion anisotropy of the crystal axes and were accompanied by hysteresis loops. The densification of Ta2WO8 ceramic was promoted by the addition of some metal oxides, and the strong ceramic of Ta30W2O81 was obtained by controlling grain growth. 相似文献
2.
Reports design considerations for singlemode interconnectable star couplers which consist of directional couplers. The Letter describes a loss peculiar to this design consideration which arises from the reciprocity of the directional couplers.<> 相似文献
3.
Masako Yudasaka Rie Kikuchi Takeo Matsui Yoshimasa Ohki Mark Baxendale Susumu Yoshimura Etsuro Ota 《Thin solid films》1996,280(1-2):117-123
Thin film formation of graphite by chemical vapor deposition using 2-methyl-1,2′-naphthyl ketone as a starting material was carried out on Ni film substrates. On Ni films directly deposited on quartz glass, the graphite films were obtained when the Ni film thickness was above 1 000 Å and above 5 000 Å at 700 °C and 1 000 °C, respectively. Depositions on thinner Ni film substrates comprise amorphous carbon (a-C) or graphite tubes which was owing to the thermal coagulation of the Ni film into droplets. On the other hand, graphite film was obtained on the Ni film with thickness 10 Å when a-C was inserted between the Ni film and the quartz glass. The coagulation of the Ni film is considered to be avoided by inserting a-C layer. 相似文献
4.
H Ota T Katsuyama S Nakajima H El-Zimaity JG Kim DY Graham RM Genta 《Canadian Metallurgical Quarterly》1998,29(8):846-850
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined. 相似文献
5.
Motofumi Suzuki Kohei Kinoshita Shinji Jomori Hidehiko Harada Kaoru Nakajima Kenji Kimura 《Thin solid films》2007,515(22):8281-8284
The initial stage of iron silicide formation is investigated by high-resolution Rutherford backscattering spectroscopy. During the Fe deposition on Si(001) at 470 °C, the formation of FeSi2 is confirmed by the surface peak analysis. Initially, FeSi2 grows epitaxially so that one of the major crystallographic axes is parallel to the <111> axis of the Si substrate. With increasing Fe deposition, the deviation between the major crystallographic axis of the silicide region and Si<111> increases although the electron diffraction pattern is independent of the amount of Fe deposition. Therefore, the subsurface crystallographic structure of iron silicide is transformed from a cubic-like to a low-symmetry structure. 相似文献
6.
Manipulation of Micro Solid Particles and Induced Flows in Water by Laser Irradiation 总被引:1,自引:0,他引:1
Q-switch for pulsing laser beam and Galvano scanner for rapid scanning laser beam were adapted to manipulatemicro solid particles in a water droplet.The trapping of fine particles at micron-sized diameters by a YAG lasersystem,induced flows,and the induced motion of the particles by laser beam irradiations are discussed.Particlerotations are observed by using anisotropic micro objects,and moreover the rotational rate with clockwise direc-tion is 22 r/min.The fragments of a cover glass were mixed in a water droplet,and their size and shape are un-even.The rotation of that non-spheres without scanning by the Galvano scanner is also observed in water. 相似文献
7.
Y Ota Y Nakano H Yamaguchi K Yoshida T Shirafuji A Adachi 《Canadian Metallurgical Quarterly》1993,20(8):1055-1057
In a 63-year-old male patient with gastric cancer having multiple liver metastases, the metastatic lesions responded well to postoperative staggered intraarterial infusion therapy with MTX and 5-FU. The intraarterial infusion therapy was administered once a week. A total of 5 courses of this therapy produced marked regression of liver metastases and remarkable necrosis. The effect was thus rated as PR. The patient is healthy and has been successfully rehabilitated. His dose is oral 5-FU (200 mg x 2). 相似文献
8.
9.
The present work has concentrated on the structure of CO2 hydrate in the NPT ensemble using SPC (simple point charge) intermolecular potential model of water by the Monte Carlo (MC) molecular simulation. A mixture of water and CO2 placed arbitrarily in a cubic cell has been used as a model system to simulate the CO2 clathrate hydrate at temperatures ranging from 150–280 K and pressure up to 10 MPa. The result shows that the obtained MC simulation agrees well with the results obtained by molecular dynamic (MD) simulation. The present work is also directed to the study of structure with TIP4P potential model of water. 相似文献
10.
A Nakamura S Tanaka H Takayama M Sakamoto H Ishii M Kusano Y Onizuka S Ota K Mitamura 《Canadian Metallurgical Quarterly》1998,37(10):884-890
A 77-year-old female was admitted to our hospital because of pyrexia and a right retroperitoneal mass. Leukocytosis and other inflammatory findings were noted. Bone-marrow aspiration revealed hypercellularity with no malignant cells. An additional mass was detected sonographically in the pelvis. The serum concentration of granulocyte colony-stimulating factor (G-CSF) was highly elevated (299 pg/ml). The tumors were removed at laparotomy, and the pelvic mass was found to arise from the ileocecal mesentery. Postoperatively, white blood cell count and serum G-CSF concentrations decreased to normal levels. The mesenteric tumor showed weakly positive immunostaining for human G-CSF, and Northern and polymerase chain reaction (PCR) analyses detected CSF and its mRNA in the mesenteric tumor. 相似文献