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排序方式: 共有1238条查询结果,搜索用时 15 毫秒
1.
2.
Ichiro Hirosawa Tetsuo Honma Kazuo Kato Naoto Kijima Yasuo Shimomura 《Journal of the Society for Information Display》2004,12(3):269-273
Abstract— We studied the influence of annealing in air on doped europium in BaMgAl10O17 by performing x‐ray absorption fine‐structure measurements. We determined the oxidation of doped divalent europium by annealing in air at over 500°C. The interatomic distance between the europium and the surrounding oxygen atoms was compressed by oxidation. It also appears that the oxidation process of europium is determined by the diffusion of oxygen into BaMgAl10O17. 相似文献
3.
4.
T Hiroshima A Higashi T Imamoto S Kusumoto K Itakura K Nishijima K Nishi 《Canadian Metallurgical Quarterly》1996,116(12):951-960
We investigated whether a chemical assay by high-performance liquid chromatography (HPLC) as an alternative to the complicated and time-consuming bioassay for CS23 mutein of recombinant human basic fibroblast growth factor (rhbFGF-CS23) using the fetal bovine heart endothelial cell line ATCC CRL 1395. Physically, chemically or enzymatically denatured rhbFGF-CS23 was subjected to heparin affinity (HA)-HPLC and the bioassay. Good agreement was observed between the results obtained by these two methods. Moreover, HA-HPLC gave much more reproducible results (RSD = 1.9%, n = 6) than the bioassay (RSD = 7.4%, n = 18). HA-HPLC is therefore a simple, accurate and reproducible alternative to the bioassay for quality control and stability studies for rhbFGF-CS23 preparations. HA-HPLC is also considered to be applicable to assays for FGFs which have heparin affinity and biological activity similar to those of the CS23 mutein. 相似文献
5.
6.
Yasuo Koide T. Kawakami Masanori Murakami N. Teraguchi Y. Tomomura A. Suzuki 《Journal of Electronic Materials》1998,27(6):772-775
Schottky barrier heights (SBHs) of a variety of metals (In, Cd, Nb, Ti, W, Cu, Ag, Au, Ni, Pt, and Se) contacting to p-ZnSe
grown by a molecular beam epitaxy method were determined by analyzing capacitance-voltage (C-V) and/or current density-voltage
(J-V) curves. The SBH values of the Au and Ni contacts were determined from intersections of straight lines of the C−2-V curves to be 1.23 and 1.13 eV, respectively. The J-V calculations provided a large SBH value of 1.2 ± 0.1 eV for a variety
of metals, indicating that the Fermi-level could be pinned at the contact interface. Reduction of the SBH values to a level
lower than 0.4 eV and/or increase of doping concentrations to a level higher than 1020 cm−3 are essential to obtain an ohmic contact with contact resistivity of around 10−3 Ω·cm2. 相似文献
7.
Toshiji Mukai Koichi Ishikawa Kenji Higashi 《Metallurgical and Materials Transactions A》1995,26(10):2521-2526
Three IN905XL aluminum alloys with fine grain (1 μm), intermediate grain (3 μm), and coarse grain (5 μm) have been developed
by a combination of mechanical alloying (MA) and conventional extrusion in order to investigate their mechanical properties
at dynamic strain rates of 1 × 103 and 2 × 103 s−1 and a quasi-static strain rate of 10-3 s−1. Flow stresses are found to increase with decreasing grain size for all the strain rates tested. Negative strain-rate sensitivity
of flow stress is observed up to 1 × 103 s−1 in both intermediate- and coarse-grained IN905XL. At the highest strain rate of 2 × 103 s−1 however, all samples showed a positive strain-rate sensitivity of strength. Total elongation at high strain rates is generally
larger than that at low strain rates. Total elongation also decreases with grain size for all the strain rates. This decrease
in elongation results from an initiation of microcracks at interfaces between the matrix and particles finely dispersed near
grain boundary regions, introduced during MA processing; then, this initiation leads elongation of alloys to small limited
values.
Formerly with the Department of Mechanical Systems Engineering, University of Osaka Prefecture.
This article is based on a presentation made in the symposium “Dynamic Behavior of Materials,” presented at the 1994 Fall
Meeting of TMS/ASM in Rosemont, Illinois, October 3-5, 1994, under the auspices of the TMS-SMD Mechanical Metallurgy Committee
and the ASM-MSD Flow and Fracture Committee. 相似文献
8.
High performance liquid chromatographic separation of a series of mono-, di- and trihydroxylated 5β-cholanic acids which differ
only in position and configuration of hydroxyl groups at positions C-3, C-7 and/or C-12, is reported. The C-24 free acids
were derivatized to four different classes of UV-sensitive esters, i.e.,p-bromophenacyl (BP),m-methoxyphenacyl (MP), 4-nitrophthalimidemethyl (NPM) and 9-anthrylmethyl (AM) esters, and chromatographed on two, variants
of C18 reversed-phase columns (Nova-Pak C18 and Zorbax ODS) with methanol-water systems as mobile phase. Separation efficiency and elution order of some isomeric pairs
were influenced by both the structure of the C-24 ester groups and the nature of the columns used. Excellent chromatographic
properties were found for those derivatives, particularly for the NPM esters. 相似文献
9.
Yasuo Suzuki Ryoetsu Yoshino Hisashi Saitoh Kazunori Fukushi Yoshikazu Sonehara 《Journal of Alloys and Compounds》1992,180(1-2):383-389
The mean molal activity coefficients of aqueous scandium chloride, nitrate, bromide and perchlorate solutions were determined at 25.0° for dilute to saturated concentrations, together with the activities of water. In the dilute solutions of scandium halides, the activity coefficients were obtained from electromotive force measurements on galvanic cells, and the osmotic coefficients of all four solutions above 0.1 mol kg−1 were determined from the isopiestic measurements. Least-squares equations were fitted to these coefficients, which were then used to calculate the mean molal activity coefficients and water activities. The relationships between these results and the corresponding activity data for other rare earth salts, and to the cation hydration and ionic interactions, are discussed. The results on scandium perchlorate solutions suggested that the inner-sphere hydration number of tervalent scandium ion may be seven. 相似文献
10.
Yuanning Chen Myricks R. Decker M. Liu J. Higashi G.S. 《Electron Device Letters, IEEE》2003,24(5):295-297
As CMOS device dimensions scale down to 100 nm and beyond, the interface roughness between Si and SiO/sub 2/ has become critical to device performance and reliability. Si/SiO/sub 2/ interface roughness degrades channel mobility decreasing drive currents. The authors have used atomic force microscopy to study surface roughness in the processing of 0.16 /spl mu/m CMOS integrated circuits. All of the process steps that could potentially affect the interface roughness have been studied. The results show that oxidation is the major contributor to the interface roughness. The rms roughness is found to be linearly dependent on oxide thickness. Transistors with Si/SiO/sub 2/ interface rms roughness that has been reduced from 1.6 to 1.1 /spl Aring/ by reducing oxide thicknesses show improved device drive currents. This technique for interfacial smoothing and device performance improvement has the advantage of being easily implemented in today's technology. 相似文献