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51.
R. Kondo Y. Tsutsumi H. Doi N. Nomura T. Hanawa 《Materials science & engineering. C, Materials for biological applications》2011,31(5):900-905
The effects of Pt and Pd addition to a Zr-20Nb alloy on its microstructure and mechanical property, as well as the elution of metals from the alloys in lactic acid solution, were investigated. The microstructure was characterized with an X-ray diffractometer (XRD), an optical microscope (OM), and a transmission electron microscope (TEM). The mechanical properties were evaluated by a tensile test. The β phase is dominantly observed in the Zr-20Nb as well as in the Pt-added and Pd-added Zr-20Nb alloys. Needle-like microstructures are observed in equiaxed grains in all alloys. Pd addition to the Zr-20Nb alloy suppresses ω phase formation more than Pt addition does. The 0.2% offset yield strength and the ultimate tensile strength of the Pt-added and Pd-added Zr-20Nb alloys increase with the Pt and Pd concentrations. XRD analysis revealed that the lattice parameter of β-Zr in the Pt-added and Pd-added Zr-20Nb alloys decreases with the Pt and Pd concentrations. Pt and Pd solute in β-Zr as a substitutional element and contribute to the increase in the strength by solid solution hardening. The addition of 2Pt and 2Pd to the Zr-20Nb alloy also improves metal elution from the alloys in lactic acid solution. 相似文献
52.
Takuya Takahashi Motoya Suzuki Ryuji Nomura Yuichi Okuda Koji Kamiya Takenori Numazawa Peter Shirron 《Microgravity science and technology》2011,23(4):365-372
Superfluid 4He was produced on a small jet plane for the first time using a small GM-refrigerator to condense the liquid and a scroll
pump to get the superfluid by evaporation. The surface wave on superfluid under 0.5g
E, 0.1g
E and 0.05g
E, together with 2g
E and 1g
E, was successfully examined by an optical method utilizing parabolic flight. Here, g
E is the gravitational constant on the ground. Assuming that only the fundamental mode was excited as determined by the sample
cell width, the resonance peak in the frequency domain was well reproduced by the gravity wave with corresponding gravity
constant. 相似文献
53.
Weixiao Huang Chow T.P. Niiyama Y. Nomura T. Yoshida S. 《Electron Device Letters, IEEE》2009,30(10):1018-1020
We report on the experimental demonstration of a novel n-channel GaN epilayer RESURF GaN MOSFET with good tradeoff between breakdown voltage and specific on-resistance for the first time. Device with 4-mum channel length and 16-mum RESURF length has breakdown voltage up to 730 V with specific on-resistance 34 mOmegamiddotcm2 (VG - VT = 20 V), best reported to date. 相似文献
54.
Tsuyoshi Nomura Masahiro Ikeda Seiji Ishiyama Kazuhide Mita Toshiki Tamura Takahiro Okada Kazuhito Fujiyama Akihiro Usami 《Journal of Bioscience and Bioengineering》2010,110(4):386-391
In insects, β-N-acetylglucosaminidase (GlcNAcase) participates in critical physiological processes such as fertilization, metamorphosis, and glycoconjugate degradation. Insects produce glycoproteins carrying paucimannosidic-type N-glycans, the terminal GlcNAc residue of which is cleaved by a GlcNAc-linkage specific GlcNAcase, also known as the fused lobes (FDL) protein. To obtain information on the structure of GlcNAcases and insight into their contribution to physiological processes, we cloned Bombyx mori FDL (BmFDL) from silkworm larvae. The full-length cDNA (1.9 kb) encoded a protein of 633 amino acids with 42% amino acid sequence identity to Drosophila melanogaster FDL (DmFDL). Recombinant BmFDL cleaved only β-1,2-linked GlcNAc residues from the α-1,3 branch of biantennary N-glycan. This substrate specificity was similar to that of DmFDL. Microsomal FDL activity was inhibited by anti-BmFDL antibodies. Taken together, our results suggest that BmFDL is a N-glycan-processing GlcNAcase in B. mori. 相似文献
55.
The isotope effects of gadolinium in Gd-EDTA ligand exchange system were studied by means of ion exchange chromatography. The separation coefficients of gadolinium isotopes, epsilon, and the local enrichment factors, beta, were calculated from the observed isotopic ratios at the front and rear boundaries of the gadolinium adsorption band. Clear mass independent anomalies were observed in the isotope effects of 155Gd and 157Gd. The relation between the isotope effects of gadolinium isotopes, studied by the three-isotope plot and the separation coefficient methods, and the mass of gadolinium isotopes was found to be related to the change in the mean square radius of the nuclear charge distribution parameter, (r2), of these isotopes, which suggests that the nucleus shape and size highly affect the gadolinium isotope effects in chemical exchange reactions. 相似文献
56.
Techniques for measuring aberrations in lenses used in photolithography with printed patterns 总被引:3,自引:0,他引:3
In optical lithography, it is a serious problem that aberrations in projection lenses reduce the imaging quality. Therefore techniques to measure the aberrations are required that will predict the adverse effects of aberrations on lithographic imagery and reduce them. We present a measurement method that uses a fine grating and its imaging condition to quantify coma, astigmatism, and spherical aberration. With this method, these aberrations can be described with simple expressions from the measured results. Application of this method revealed the coma of Zernike polynomials for our krypton fluoride (KrF) excimer-laser scanner. 相似文献
57.
We report a 68-year-old man who had immediate-type heat urticaria with systemic symptoms. Immersing his hand in water at 42 degrees C (heat challenge test) produced an urticarial response, with an increase in the plasma histamine level from 0.26 to 7.64 ng/mL. Administration of oral antihistamines alone did not suppress either the urticarial response or the increase in plasma histamine. However, a combination of antihistamines and desensitization improved the skin lesions and reduced the plasma histamine level. The heat challenge test subsequently provoked a negative response and there was no increase in plasma histamine level 3 months after starting the combination therapy. These results indicate that the histamine level reflected the result of the heat challenge test and the amelioration of the skin eruption. 相似文献
58.
59.
60.
A Matsumura O Yanase T Motomiya Y Tokuyasu H Sakurada S Nomura T Teshima Y Hiyoshi M Sugiura 《Canadian Metallurgical Quarterly》1995,18(4):234-235
Sarcoidosis is a multisystem granulomatous disorder of unknown etiology which mainly affects the lungs, skin, the lymphoreticular system, and the heart. We report a case of cardiac sarcoidosis in which a remarkably thin ventricular septum was demonstrated on two-dimensional echocardiography. 相似文献