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981.
Furuya H Nakao H Yamada I Ruan YF Yap YK Yoshimura M Mori Y Sasaki T 《Optics letters》2000,25(21):1588-1590
We developed a Gd(x)Y(1-x)Ca(4)O(BO(3))(3) (GdYCOB) crystal for control of optical birefringence. GdYCOB crystals were successfully used to generate noncritical phase-matched (NCPM) second and third harmonics of 1064-nm lights. However, we observed degradation of third-harmonic-generation (THG) output power and distortion of the beam pattern as a result of photoinduced damage and thermal dephasing. The photoinduced damage was classified into two types. One was gray-track and the other was photorefractive damage. It seems that these types of damage were similar to the types of damage that occurred with KTiOPO(4) and LiNbO(3) crystals. We tried to circumvent this problem by crystal heating. Photoinduced damage of GdYCOB was overcome by elevation of the crystal temperature, and NCPM THG (355-nm) output power from heated GdYCOB increased to 9 mW (62.5 kHz). 相似文献
982.
The anion-selectivity of the surface of a polymer ultrathin film incorporating an amphiphilic ruthenium(II) polypyridine complex with diperchlorate was examined using X-ray absorption spectroscopy with the total electron-yield method. The adsorbed species on the film surface were found to depend on the chemical composition in water where the film was prepared. By combining the X-ray absorption spectra with a molecular-orbital calculation, the molar ratio (MClO4/MRu) between the ClO4- ions and the Ru head group on the film surface could be semi-quantitatively analyzed; it was 0.88 for a film prepared on fresh water, and 1.4 for one prepared on old water. 相似文献
983.
984.
Y. Yamada K. Katsumata Y. Ono K. Yamaguchi 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(3):419-423
Reactions of laser-evaporated iron atoms with ethylene molecules were investigated. The reaction products were trapped in a low-temperature matrix observed by Mössbauer and infrared spectroscopies. Fe(C2H4) was produced at low ethylene concentration, and Fe(C2H4)2 was obtained as the major product at higher ethylene concentration. The assignments were confirmed through molecular orbital calculations. 相似文献
985.
986.
The representative (E)-1-alkenyldisiamylboranes and (E)-1-alkenyl-1,3,2-benzodioxaboroles readily obtainable hydroboration of 1-alkynes react with 1-alkenyl halides or 1-alkynyl halides in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium and base to give corresponding conjugated (E)-dienes or (E)-enynes with high regio- and stereospecificity in good yields, respectively. 相似文献
987.
Shuichi Iwadare Yoshikazu Shizuri Kiyoyuki Yamada Yoshimasa Hirata 《Tetrahedron letters》1974,15(13):1177-1178
Synthesis of trichotomine, a blue pigment obtained from thunb. 相似文献
988.
Yasuji Yamada Sukeji Suzuki Kazuo Iguchi Hiroyuki Kikuchi Haruo Horiai Fumio Shibayama 《Tetrahedron letters》1980,21(40):3911-3914
The relative and absolute stereochemistry of two 13-membered carbocyclic cembranolides was determined as shown in and on the basis of NMR spectral evidence. 相似文献
989.
990.