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51.
52.
Takeo Taguchi Ginjiro Tomizawa Akihiro Kawara Masaharu Nakajima Yoshiro Kobayashi 《Journal of fluorine chemistry》1988,40(2-3):171-182
Reaction of 1-phenylsulfonul-3,3,3-trifluoropropene(1) with carbonyl-stabilized enolate anions smoothly proceeded to give the addition products(7) in good yield while with an alkyl-lithium or Grignard reagent the formation of the vinyl anion(8) was one of the reaction pathways. Reaction of 1 with the chiral nucleophiles(11, 16) was carried out to give the functionalized trifluoromethylated compounds(13, 7b) in 4-43% ee 相似文献
53.
Simultaneous measurements of the electrical resistance and X-ray diffraction under pressure have revealed that ZnTe exhibits two subsequent structural transitions at approximately 85 and 130 kbar, accompanied by a conspicuous rise and drop in the resistance, respectively. 相似文献
54.
The size distribution of new vesicles formed after addition of oleate in different forms to preformed egg yolk phosphatidylcholine (EggPC) vesicles was studied by gel exclusion chromatography. The addition of oleate to preformed vesicles resulted in the formation of new small vesicles. Fission of preformed vesicles incorporated by oleate and partial solubilization of the vesicles by addition of oleate in micellar form were involved in the process of the new small vesicle formation. 相似文献
55.
56.
Masami Hasegawa Masaharu Tanemura 《Annals of the Institute of Statistical Mathematics》1976,28(1):509-519
Summary In this paper the tesselation of territories is discussed. When a mass of animals with teritoriality is introduced at random
simultaneously into a finite two-dimensional (2D) region, territories are gradually formed and finally settle to a steady
state. A model calculation for this process is carried out, where a Voronoi polygon is assumed as a territory. Comparisons
are made between the model calculation and Barlow's observation on an artificial population of mouthbreeder fish. Differences
between 1D and 2D case are also discussed.
The Institute of Statistical Mathematics 相似文献
57.
58.
Haruyuki Inui Norihiko L. Okamoto Takashi Hashimoto Katsushi Tanaka Masaharu Yamaguchi 《哲学杂志》2013,93(12):1463-1478
The defect structures in orthorhombic C54 crystallites in thin films of Mo-doped TiSi 2 produced by co-sputtering have been investigated by transmission electron microscopy. Almost all C54 crystallites contain a twin boundary parallel to (101), dividing a crystallite into two regions, each of which also contains many thin twins with the habit plane parallel to (001), which is inclined by about 45° from (101). Both of the two regions divided by the twin boundary parallel to (101) tend to have facets on (001) as well as thin twins with the habit plane parallel to (001). As a result, C54 crystallites exhibit a characteristic shape just like an oak leaf. While twins with the (001) habit plane have been observed in C54 crystallites in both binary and Mo-doped TiSi 2 thin films, those with the (101) habit plane are present only in Mo-doped TiSi 2 thin films. The twinning elements for (101) twins are determined to be K 1 = (101), , K 2 = (001) and m2 = [100]. The origin of (101) twins in Mo-doped TiSi 2 is discussed in terms of the change in the c / a axial ratio upon alloying TiSi 2 with Mo. 相似文献
59.
Masaharu Ueno Satoshi D. Ohmura Makoto Wada Norikazu Miyoshi 《Tetrahedron letters》2019,60(7):570-573
We developed an environmentally friendly method for aerobic oxidation of alcohols using a commercially available, relatively benign bismuth salt as a catalyst. We found that the catalytic combination of BiBr3 with nitric acid is key for enhancing the reactivity. The reaction proceeds well under air, making the use of pure oxygen unnecessary. Each of the primary or secondary alcohols tested was oxidized to the corresponding aldehydes or ketones using this protocol. 相似文献
60.
Fluorine-doped silica glasses are produced by the sol-gel method for optical fiber preforms. In order to dope fluorine into silica glass, fluorinated silicon alkoxide, Si(OC2H5)3F, is titrated into SiO2 sol solutions. The fluorine content in silica glass depends on: the fluorine concentration in the gel, the specific surface area of SiO2 particles and the heating rate in the sintering process. Fluorine-doped silica glass with a maximum relative refractive index difference of −0.93% is obtained. Using this technique, optical fibers with a triangular refractive index profile are fabricated with a minimum optical loss of 1.6 dB/km at 1.69 μm wavelength. 相似文献