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731.
Ryo Tanabe Takahiro Yamasaki Yoshio Ashizawa Hideki Oka 《Journal of Computational Electronics》2007,6(1-3):49-53
In this paper, we focus on uniaxial and biaxial strain technologies, and we also investigate an optimum combination of strain
method and channel direction. We linked the first principles band calculation program to the FUJITSU ensemble full band Monte
Carlo simulator FALCON directly, which enables to incorporate arbitrary Si band structures such as uniaxial and biaxial strained-Si
into device characteristics analysis. We show that the combination of biaxial tensile strain and <100> current for NMOS, and
compressive uniaxial strain and <110> channel for PMOS are optimum methods for current enhancement. However, considering technological
difficulties and process cost, it is one of the candidate methods to use the combination of uniaxial tensile strain and <100>
channel direction for NMOS and that of uniaxial compressive strain and <110> channel direction for PMOS. 相似文献
732.
Dr. Hendris Wongso Dr. Tomoteru Yamasaki Dr. Katsushi Kumata Prof. Maiko Ono Prof. Makoto Higuchi Prof. Ming-Rong Zhang Prof. Michael J. Fulham Prof. Andrew Katsifis Prof. Paul A. Keller 《ChemMedChem》2021,16(12):1902-1916
A series of fluorescent probes from the 6-chloro-2-phenylimidazo[1,2-a]pyridine-3-yl acetamides ligands featuring the 7-nitro-2-oxa-1,3-diazol-4-yl (NBD) moiety has been synthesized and biologically evaluated for their fluorescence properties and for their binding affinity to the 18-kDa translocator protein (TSPO). Spectroscopic studies including UV/Vis absorption and fluorescence measurements showed that the synthesized fluorescent probes exhibit favorable spectroscopic properties, especially in nonpolar environments. In vitro fluorescence staining in brain sections from lipopolysaccharide (LPS)-injected mice revealed partial colocalization of the probes with the TSPO. The TSPO binding affinity of the probes was measured on crude mitochondrial fractions separated from rat brain homogenates in a [11C]PK11195 radioligand binding assay. All the new fluorescent probes demonstrated moderate to high binding affinity to the TSPO, with affinity (Ki) values ranging from 0.58 nM to 3.28 μM. Taking these data together, we propose that the new fluorescent probes could be used to visualize the TSPO. 相似文献
733.
Influence of vitamin A on the quality of beef from the Tajima strain of Japanese Black cattle 总被引:1,自引:0,他引:1
Influence of vitamin A on the beef quality of the Tajima strain of Japanese Black cattle was studied. Marbling scores were correlated with serum vitamin A concentrations just before slaughter (r = -0.38). The mean marbling score of the low vitamin A group that were not supplemented with vitamin A after 15 months of age was significantly higher than that of the group supplemented with high vitamin A. However, there was no significant difference in the marbling scores between the group that were not given vitamin A after 23 months of age and the high vitamin A supplemented group. These results suggest that vitamin A supplementation affects carcass marbling only if given before 23 months of age, in these cattle. 相似文献
734.
Isoko Takahashi Takanori Sugimoto Yasuo Takasu Mariko Yamasaki Yasutoshi Sasaki Youji Kikata 《Journal of Materials Science》2011,46(21):6841-6849
To improve the mechanical property of moldings made of steamed wood flour, layered wood moldings reinforced with steam-exploded
bamboo fiber was prepared. Setting the bamboo fiber weight fractions at 25, 50, and 75%, and number of layers at three-, five-,
and seven-layered wood moldings were prepared by compression molding. The results of tensile test showed that the tensile
strength as well as Young’s modulus increased along with the increase in the bamboo fiber fractions. Where the bamboo fiber
content was 75%, the tensile strength became approximately 3.8 to 5.8 times greater, and the tensile Young’s modulus became
approximately 2.5 times greater when compared to moldings of 100% wood flour. This fact shows that bamboo fiber is effective
to improve the mechanical property of wood moldings. In addition, the tensile strength also increased as the number of layers
increased. This result suggested that interfacial shear stress was produced between the layers of bamboo fiber and wood flour. 相似文献
735.
Dei K Kawase T Yoneda K Uchikoshi J Morita M Arima K 《Journal of nanoscience and nanotechnology》2011,11(4):2968-2972
Germanium (Ge) is a promising substrate for semiconductor devices in the near future. However, wet-chemical preparations that enable the control of the structure of the Ge surface have not yet been developed. In this study, the surface structure of Ge(111) after HCl treatment is characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and scanning tunneling microscopy (STM). XPS spectra revealed that purging with inert gas, such as nitrogen, is necessary to obtain a Ge surface free of oxide, probably because dissolved oxygen from air rapidly oxidizes the surface. Cl-terminated Ge surfaces are microscopically rough, but are composed of terraces and steps, as revealed by magnified STM images. Step edges run not along specific directions reflecting the crystallographic nature of the (111) surface but randomly. Many atomic-scale protrusions with the height of around 0.1 nm are dispersed on terraces. They are likely to be impurities such as carbon contaminants and water on Cl-terminated terraces attracted by Cl atoms with high electronegativity. 相似文献
736.
Sakane H Yoshimatsu A Shigetoshi T Uchikoshi J Morita M Arima K 《Journal of nanoscience and nanotechnology》2011,11(4):2962-2967
We investigate the selective adsorption of organosilane molecules (3-aminopropyltriethoxysilane (APTES) and octadecyltrichlorosilane (OTS)) at the step edges of a flattened Si(111) surface by atomic force microscopy. The flattened Si(111) surface is formed by dipping a vicinal Si(111) wafer into ultralow-dissolved-oxygen water after treatment with HF. The selective adsorption of these organosilanes is achieved only when the Si(111) sample is pretreated with a Cu-containing solution to form Cu wires along the step edges of the Si(111) surface. This is probably due to the simultaneous formation of one-dimensional Si oxide covered with hydroxyl (OH) groups underneath Cu wires during the electroless reduction of Cu ions in water. At the step edges, APTES and OTS molecules are adsorbed as disperse clusters and as rows of bumps, respectively. The reason for this difference is still unclear, but a key factor is probably the control of the moisture content in the environment. The step edges, which are functionalized by organosilane molecules with various terminations such as -NH2 and -CH3, are expected to be utilized in novel nanoscale devices and processes. 相似文献
737.
J.Z. Tong N. Harada M. Shimizu M. Tahara S. Kabashima H. Yamasaki S. Shioda 《Energy Conversion and Management》1983,23(1):11-21
The effects of ionization relaxation and ionization instability on the electrical discharge in a seeded noble gas have been studied experimentally. Experiments have been made in a simulated MHD channel in which current is applied to each of several electrode pairs with and without a magnetic field present. Experimental results have shown that unsteady current concentration in the ionization relaxation region and ionization instability induce a non-uniform and fluctuating discharge downstream. The effect of unsteady concentrated discharge in the relaxation region is reduced when current is increased. The ionization instability is also reduced when the seed becomes fully ionized. Experimental values of the effective electrical conductivity and Hall coefficient in the flow downstream have shown agreement with the values predicted by the theory for a large current. 相似文献
738.
Effect of high pressure gaseous carbon dioxide on the germination of bacterial spores 总被引:1,自引:0,他引:1
Furukawa S Watanabe T Tai T Hirata J Narisawa N Kawarai T Ogihara H Yamasaki M 《International journal of food microbiology》2004,91(2):209-213
Effect of high pressure gaseous carbon dioxide treatment (HGCT) at 6.5 MPa, 35 degrees C on the germination of bacterial spores was investigated. Germination of bacterial spores was estimated by the decrease of heat tolerance. Approximately, 40% of Bacillus coagulans and 70% of Bacillus licheniformis were germinated by HGCT for 120 min at 35 degrees C, respectively. Germination was confirmed by phase contrast microscopy. The effect of hydrostatic pressure treatment (HPT) at 6.5 MPa, 35 degrees C on the germination of B. coagulans and B. licheniformis spores were also investigated. Spores did not germinate by HPT alone at 6.5 MPa for 120 min. 相似文献
739.
S. Fukada T. Yamasaki H. Matsuo N. Mitsuishi 《International Journal of Hydrogen Energy》1991,16(12):809-813
Hydrides of intermetallic compounds of Mg2Ni have a comparatively large isotopic effect in the equilibrium isotherm between hydrogen and deuterium or tritium. An experimental and analytical study is made on the isotopic exchange reaction of hydrogen and deuterium in a Mg2Ni bed for isotope separation. Values of the first moment, the second moment and a height equivalent to a theoretical plate (HETP) are obtained on the basis of a pulse or a step change of an influent deuterium concentration. It is found that the HETP values have the least at an optimum temperature and linear velocity, and the value is about 3 cm. The activation energy of the isotopic exchange reaction of Mg2Ni is 18.5 kJ mol−1. Thus the Mg2Ni bed serves as an effective method for the isotopic separation of hydrogen isotopes. 相似文献
740.
A Duflot-Dancer C Piccoli A Rolland H Yamasaki M Mesnil 《Canadian Metallurgical Quarterly》1998,5(10):1372-1378
Gene therapy via the herpes simplex virus thymidine kinase (tk) gene and ganciclovir (GCV) treatment eliminates experimental tumors. In this approach, cells expressing the tk gene (tk+) and neighboring tumor cells which do not express the gene are killed. We have demonstrated this bystander effect is enhanced in vitro by gap junctional intercellular communication (GJIC). In order to extend our in vitro results into in vivo situations, we injected into nude mice different ratios of tk+/tk- HeLa cells, either lacking or transfected with connexin43 (Cx43), a gene coding for a gap junction protein. When GCV was administered before tumors were palpable, fewer animals developed tumors, even after a longer period, if the injected cells were mixtures of Cx43(+)-tk+ and Cx43(+)-tk- while tumor growth was not prevented with mixtures of HeLa cells not expressing Cx43, i.e. Cx43(+)-tk+/Cx43(-)-tk-. When GCV was given after the appearance of tumors, the size of the tumors from Cx43- cells was 30% reduced for 3 weeks if 50% of the injected cells were tk+. However, for cells expressing Cx43, the tumor size was 66% reduced if 10% of the cells were tk+. Such a reduction demonstrates a long-term bystander effect which is dependent on Cx43 expression. 相似文献