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41.
42.
Hideki Saitoh 《Tetrahedron letters》2010,51(4):633-3090
The reaction of 1-chlorovinyl p-tolyl sulfoxides, which were derived from ketones and chloromethyl p-tolyl sulfoxide, with lithium acetylides gave adducts in moderate to good yields. Treatment of the adducts with Grignard reagents resulted in the formation of magnesium carbenoids by the sulfoxide-magnesium exchange reaction. 1,2-Carbon-carbon insertion (1,2-CC insertion) reaction of the generated magnesium carbenoids took place to afford conjugated enynes in good to high yields. This procedure provides a good method for the synthesis of multi-substituted conjugated enynes. 相似文献
43.
This paper reports the investigation of microdroplet sample preparation for phosphate, strontium and rubidium using X-ray fluorescence. Sample filter papers were prepared by drying under several different conditions and the front and the back sides of the filter papers were measured using X-ray fluorescence (XRF), scanning electron microscopy (SEM), X-ray diffraction (XRD), and electron-probe microanalysis (EPMA). It was reported by Murata and Murokado that the elemental distribution difference between the front and the back sides after drying the filter paper led to erratic data.1 It has been found that the intensity difference between the front and the back sides was due to the condensation of the material of interest on the surface of the filter papers and the amount of the condensed material on the filter paper was related to the temperature at which the filter paper was dried. Optimum temperature at which a filter paper is dried and an appropriate internal standard are essential to reproducible measurements. 相似文献
44.
Haruo Nakayama Tomonori Saitoh Hiroshi Uchida 《Journal of inclusion phenomena and macrocyclic chemistry》1990,8(1-2):177-186
The solid-liquid phase diagrams of binary mixtures of tetrabutylammonium halogenated carboxylates with water were examined in order to confirm the formation of clathrate-like hydrates. It was found that, among thirteen carboxylates examined, four carboxylates having CH2FCOO–, CHF2COO–, CF3COO–, and CH2ClCOO–, formed a hydrate with hydration numbers around 30 and seven carboxylates having CHCl2COO–, CCl3COO–, CH2BrCOO–, CHBr2COO–, CBr3COO–, CH3CHClCOO–, and CH3CHBrCOO– formed a hydrate with hydration numbers around 23. The latter hydrate has not been reported earlier. The melting points of these newly found hydrates were fairly high: they lie between 10 and 16°C. The effect of Cl and Br atoms attached to the carbon atom of the-position of a carboxylate anion both on the type of hydrate formed and on its stability was greatly different from that of a CH3 group attached to the same position of the carboxylate anion.Dedicated to Dr D. W. Davidson in honor of his great contributions to the sciences of inclusion phenomena. 相似文献
45.
Optical trapping forces of polystyrene microspheres are analyzed both theoretically and experimentally, and comparisons are
made between the two. Discrepancies are mainly caused by straight-ray approximation for axial trapping, and by trapping-position
vertical displacement due to gravity for transverse trapping. 相似文献
46.
Takayuki Yamanaka Hideki Fukano Ken Tsuzuki Munehisa Tamura Ryuzo Iga Matsuyuki Ogasawara Yasuhiro Kondo Tadashi Saitoh 《光学学报》2003,23(Z1)
A comprehensive analysis of multi-quantum-well electroabsorption modulators buried with semi-insulating (SI)-InP is presented. We quantitatively demonstrate that suppression of Zn diffusion into the burying and optical core layers plays a key role in high-speed and high-extinction operation. 相似文献
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K. Suzuki M. Takahashi M. Saitoh 《Applied Physics A: Materials Science & Processing》1999,69(7):S263-S266
This paper presents for the first time experimental results which show a crucial role of the local Si-H bonding structures in Si precursors for crystallinity of polycrystalline silicon (p-Si), obtained by an excimer laser crystallization (ELC) process. This role was revealed in the distinct differences among (111) lattice plane spacings of p-Si according to deposition and dehydrogenation conditions of the precursors. It was also found that preablation behaviors, especially ebullition of the melt, are highly sensitive to the precursors. These results provide an important guide for the selection of the most adequate precursor in production, and also contribute an understanding of the mechanism of the ELC process. 相似文献