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排序方式: 共有951条查询结果,搜索用时 15 毫秒
81.
Kiyoshi Kusabiraki Shigeoki Saji Tomoya Tsutsumi 《Metallurgical and Materials Transactions A》1999,30(8):1923-1931
A Ni-18Cr-16Fe-5Nb-3Mo alloy (a modified alloy 718, referred to herein as 718M), in which the γ″ phase is the only precipitation-strengthening phase, was made by substituting most of the aluminum and titanium in INCONEL
718 with niobium. The specimens of alloy 718M were solid-solution heat treated, aged at 1033 to 1073 K for up to 360 ks, and
cold rolled to a reduction of 10 to 15 pct at room temperature. After subsequent annealing heat treatments, at the same temperatures
used for aging, the morphological and structural changes of the γ″ precipitates were investigated by transmission electron microscopic observation using carbon extraction replicas. Although
stacking faults were not noticed in the γ″ precipitates extracted from the aged 718M alloy, stacking faults introduced in the {112}
γ″
planes by cold rolling of the samples were confirmed. The stripelike contrast due to the stacking faults becomes less clear
with increasing annealing time. With longer annealing times, necking occurs between the stripes, which eventually separate
into plural particles. The selected-area electron diffraction (SAED) patterns of the cold-rolled and annealed particles show
that the metastable γ″ precipitates with stacking faults are transformed gradually into a stable δ phase. In this article, we discuss the basis of morphological and structural changes in detail.
INCONEL is a trademark of INCO Alloys International, Inc., Huntington, WV. 相似文献
82.
Y Kajiyama M Tsurumaru H Udagawa K Tsutsumi Y Kinoshita M Ueno H Akiyama 《Canadian Metallurgical Quarterly》1998,45(23):1442-1445
BACKGROUND/AIMS: In the chemotherapy of recurrent gastric cancer with 5-fluorouracil and folinic acid, an interesting phenomenon, the reduction of jaundice and improvement of liver function, was observed. The aim of this study was to investigate the mechanism of this phenomenon, and to confirm a choleretic effect of folinic acid. METHODOLOGY: The bile duct of anesthetized rats was catheterized, and bile was collected. Bile volume and total bile acid production following intraperitoneal administration of folinic acid were determined and compared to those of control rats. RESULTS: Both bile volume and total bile acid production increased following intraabdominal administration of folinic acid. CONCLUSIONS: Folinic acid has a newly described pharmacologic effect of stimulating bile acid-dependent choleresis. It is possible that folinic acid may become a new drug for the treatment of jaundice or for the improvement of overall liver function. 相似文献
83.
BACKGROUND/AIMS: Because heavy drinkers do not always develop alcoholic liver disease (ALD), genetic factors may be involved. Cytochrome P4502E1 is the main enzyme that oxidizes ethanol in the non-alcohol dehydrogenase pathway. Recently, the presence of genetic polymorphisms of this enzyme was confirmed. In the present study, the genotypes of P4502E1 were analyzed in patients with or without ALD. METHODS: After extraction of DNA from white blood cells, genotypes of P4502E1 were determined by restriction fragment length polymorphisms using two endonucleases. The genotypes were separated into three types: type A, type C (homozygous for the c1 or c2 gene), and type B (heterozygous for both genes). RESULTS: In 50 patients with ALD, the prevalence of type A was 16% and that of the c2 gene was 84%. The genotypes in 10 heavy drinkers without ALD were all type A. In 34 patients with non-alcoholic liver disease and in 88 patients without hepatobiliary disease, the prevalence of type A was 65% and 71%, respectively, indicating a significantly higher prevalence of the c2 gene in ALD. In healthy nonalcoholics, the prevalence of type A was 62%-68%. CONCLUSIONS: These results suggest that polymorphisms of P4502E1 may be related to the development of ALD. 相似文献
84.
In these years, a lot of environmental problems such as air pollution and exhaustion of fossil fuels have been discussed intensively. In our laboratory, a hydrogen-fueled propulsion system has been researched as an alternative to conventional systems. A hydrogen-fueled propulsion system is expected to have higher power, lighter weight and lower emissions. However, for the practical use, there exist many problems that must be overcome. Considering these backgrounds, jet engines with hydrogen-fueled combustion within a turbine blade passage have been studied. Although some studies have been made on injecting and burning hydrogen fuel from a stator surface, little is known about the interaction between a tip leakage vortex near the suction side of a rotor tip and hydrogen-fueled combustion. The purpose of this study is to clarify the influence of the tip leakage vortex on the characteristics of the 3-dimensional flow field with hydrogen-fueled combustion within a turbine blade passage. Reynolds-averaged compressible Navier-Stokes equations are solved with incorporating a k-ε turbulence and a reduced chemical mechanism models. Using the computational results, the 3-dimensional turbulent flow field with chemical reactions is numerically visualized, and the three-dimensional turbulent flow fields with hydrogen combustion and the structure of the tip leakage vortex are investigated. 相似文献
85.
Tomohiro Fujii Jun Nishikawa Soichiro Fukuda Naoto Kubota Junzo Nojima Koichi Fujisawa Ryo Ogawa Atsushi Goto Koichi Hamabe Shinichi Hashimoto Aung Phyo Wai Hisashi Iizasa Hironori Yoshiyama Kohei Sakai Yutaka Suehiro Takahiro Yamasaki Taro Takami 《International journal of molecular sciences》2022,23(18)
DNA methylation of both viral and host DNA is one of the major mechanisms involved in the development of Epstein–Barr virus-associated gastric carcinoma (EBVaGC); thus, epigenetic treatment using demethylating agents would seem to be promising. We have verified the effect of , which was discovered by screening for demethylating agents. MC180295 inhibited cell growth of the EBVaGC cell lines YCCEL1 and SNU719 in a dose-dependent manner. In a cell cycle analysis, growth arrest and apoptosis were observed in both YCCEL1 and SNU719 cells treated with MC180295. MKN28 cells infected with EBV were sensitive to MC180295 and showed more significant inhibition of cell growth compared to controls without EBV infection. Serial analysis of gene expression analysis showed the expression of genes belonging to the role of BRCA1 in DNA damage response and cell cycle control chromosomal replication to be significantly reduced after MC180295 treatment. We confirmed with quantitative PCR that the expression levels of BRCA2, FANCM, RAD51, TOP2A, and CDC45 were significantly decreased by MC180295. LMP1 and BZLF1 are EBV genes with expression that is epigenetically regulated, and MC180295 could up-regulate their expression. In conclusion, MC180295 inhibited the growth of EBVaGC cells by suppressing DNA repair and the cell cycle. MC180295相似文献
86.
T. K. Lee Chang-Ming Ho Naoto Nagaosa Wei-Cheng Lee 《Journal of Low Temperature Physics》2003,131(3-4):169-179
Trial wavefunctions, constructed explicitly from the unique 2-dimensional Mott insulating state with antiferromagnetic order, are proposed to describe the low-energy states of a Mott insulator slightly doped with holes or electrons. With the state behaving like charged quasi-particles with well-defined momenta, a rigid band is observed. These states have much less pairing correlations than previously studied ones. Small Fermi patches obtained are consistent with recent experiments on high T
c cuprates doped lightly with holes or electrons. States showing the incoherent and spin-bag behaviors are also discussed. Using these wavefunctions, a number of results obtained by exact calculations are reproduced. 相似文献
87.
M Kojima N Tsutsumi H Nagata F Itoh A Ujiie K Kawashima H Endo M Okazaki 《Canadian Metallurgical Quarterly》1994,17(4):504-508
The effect of 3,9-bis(N,N-dimethylcarbamoyloxy)-5H-benzofuro[3,2-c]quinoli ne-6-one designated as KCA-098) on the bone mineral metabolism of chick embryonic bone was examined. KCA-098 dose-dependently inhibited bone resorption of cultured chick embryonic femora and calvariae. It increased the length, dry weight, and calcium and phosphorus contents of 9-d-old chick embryonic femurs cultivated for 6 d, indicating that it stimulated bone formation. These results show that KCA-098 has the unique effects of inhibiting bone resorption and stimulating bone formation of chick embryo. In addition, in an in vivo experiment, oral administration of KCA-098 (3.0 mg/kg/d) for 16 weeks led to an increase in calcium and phosphorus content as well as an increase in the amount of force required to break the femur from ovariectomized rats, suggesting that it may be useful for the treatment of bone diseases. 相似文献
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