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141.
Mouleeswaran Deivasigamani Tadanobu KoyamaYasuhiro Hayakawa 《Journal of Crystal Growth》2009,311(12):3314-3318
Selective epitaxial growth of a GaAs layer on SiNx masked Si-doped semi-insulating (1 0 0) GaAs substrate was performed by current-controlled liquid-phase epitaxy (CCLPE) in the conventional liquid-phase epitaxy. Experiments were carried out with and without the application of electric current. Surface morphology of (1 0 0) facet of the grown layer and the vertical and lateral growth rates were significantly improved under applied electric current. A thick layer of about 330 μm was achieved at relatively low growth time of 6 h with a current density of 20 Acm−2. The epitaxial growth is realized by both electromigration of the solute and supercooling under a constant rate of furnace cooling. The dislocation density of the grown layer was significantly reduced, compared with that of the substrate (4×104 cm2). 相似文献
142.
Kobayashi K Fujii Y Hirayama Y Kobayashi S Hayakawa I Kigoshi H 《Organic letters》2012,14(5):1290-1293
A hybrid compound consisting of aplyronine A and mycalolide B was synthesized, and its biological activities were evaluated. The hybrid compound was found to have somewhat more potent actin-depolymerizing activity than aplyronine A. In contrast, the hybrid compound possessed about 1000-fold less cytotoxicity than aplyronine A. These results indicated that there is no direct correlation between actin-depolymerizing activity and cytotoxicity. 相似文献
143.
144.
Methodological advances in multiple scattering theory (MST) in both wave and Green's function versions are reported for the calculation of electronic ground and excited state properties of condensed matter systems with an emphasis on core-level photoemission and absorption spectra. Full-potential MST is reviewed and extended to non-local potentials. Multichannel MST is reformulated in terms of the multichannel density matrix whereby strong electron correlation of atomic multiplet type can be accounted for in both ground and excited states. 相似文献
145.
G. L. Zhang C. L. Zhang H. Q. Zhang C. J. Lin D. Y. Pang X. K. Wu H. M. Jia G. P. An Z. D. Wu X. X. Xu F. Yang Z. H. Liu S. Kubono H. Yamaguchi S. Hayakawa D. N. Binh Y. K. Kwon N. Iwasa M. Mazzocco M. La Commara M. Romoli C. Signorini 《The European Physical Journal A - Hadrons and Nuclei》2012,48(5):1-7
The quasi-elastic scattering angular distribution of the proton drip line nucleus 17F on a 12C target was measured at 60 MeV. The experimental data have been compared with the theoretical analysis based onto optical model and continuum discretized coupled channels (CDCC). The couplings between breakup and elastic scattering channels, and between inelastic and elastic scattering channels resulted very weak. In order to explore the breakup effects the total reaction cross-section was deduced from the angular distribution of the quasi-elastic scattering data, and then compared with the existing data for the other weakly and tightly bound nuclei on 12C target using a universal function. From this comparison, we concluded that the breakup effect is not important for weakly bound projectiles on the light target as obtained also with the CDCC analysis. 相似文献
146.
K Ogura M Nishiuchi AS Pirozhkov T Tanimoto A Sagisaka TZh Esirkepov M Kando T Shizuma T Hayakawa H Kiriyama T Shimomura S Kondo S Kanazawa Y Nakai H Sasao F Sasao Y Fukuda H Sakaki M Kanasaki A Yogo SV Bulanov PR Bolton K Kondo 《Optics letters》2012,37(14):2868-2870
Using a high-contrast (10(10):1) and high-intensity (10(21) W/cm(2)) laser pulse with the duration of 40 fs from an optical parametric chirped-pulse amplification/Ti:sapphire laser, a 40 MeV proton bunch is obtained, which is a record for laser pulse with energy less than 10 J. The efficiency for generation of protons with kinetic energy above 15 MeV is 0.1%. 相似文献
147.
W. Li C. Wen M. Yamashita T. Nonomura Y. Hayakawa H. Tatsuoka 《Journal of Crystal Growth》2012,340(1):51-55
β-FeSi2 bulk crystals were grown by a molten salt method with Cu or Co addition. The effect of the Cu or Co addition on the structural, electrical and thermoelectric properties was investigated. A p-type semiconducting β-FeSi2 crystal was obtained without any impurity addition. On the other hand, n-type β-FeSi2 crystals were obtained by Co doping with 1.5–4 mol% addition. For the Cu addition, β-FeSi2 crystals with large diameter columnar domains were obtained, and an increased β-phase formation was observed. In addition, a slight decrease in the carrier density and a slight increase in the Hall mobility were observed, probably due to the elimination of crystalline defects. The structural and electrical modifications of the β-FeSi2 crystals by the impurity addition is discussed. 相似文献
148.
149.
Tomoko Kemmei Shuji Kodama Hironori Fujishima Atsushi Yamamoto Yoshinori Inoue Kazuichi Hayakawa 《Analytica chimica acta》2012
The chelating agent EDTA is widely used, and as a result is showing up widely in the aquatic environment. Here we describe a preconcentration procedure for measuring EDTA concentration in sea water samples by HPLC. The procedure consists of forming an Fe(III) complex followed by solid-phase extraction using an activated carbon cartridge. After the preconcentration, EDTA was quantified by HPLC with ultraviolet detection (260 nm). The enrichment permitted the determination of EDTA at concentrations as low as 1 nM. Good recoveries were obtained for both brackish and full-strength sea water with high repeatability (RSD < 6%). The method was applied to sea water samples taken from near the mouth of the Oyabe River in Japan. 相似文献
150.
Yohsuke Satoh Takuya Yamada Yuto Onozaki Dai Kawamura Ichiro Hayakawa Hideo Kigoshi 《Tetrahedron letters》2012,53(11):1393-1396
Synthesis of the macrolactone part of biselides A (1) and B (2), marine cytotoxic polyketides, was achieved by using regioselective allylic oxidation as a key step. 相似文献