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301.
Noriko Mizoguchi 《Journal of Differential Equations》2006,231(1):182-194
The present paper is concerned with a Cauchy problem for a semilinear heat equation
(P) 相似文献
302.
Zhenjun Du Toshihiro Kawatani Kazuhide Kataoka Rikiya Omatsu Junzo Nokami 《Tetrahedron》2012,68(11):2471-2480
Isopropyl, ethyl, and methyl 2-(2-benzothiazolylsulfinyl)acetates have been found to be useful synthetic reagents for sulfinyl-Knoevenagel reaction with various aldehydes to give directly the corresponding 4-hydroxyalk-2-enoates [R′CH(OH)CHCHCO2R], which are ubiquitous structures in biologically active natural products and useful building blocks for organic synthesis of chiral compounds. From the optically pure (R)-2-(2-benzothiazolylsulfinyl)acetates (>99% ee) prepared by the enzymatic kinetic resolution of (±)-2-(2-benzothiazolylsulfinyl)acetates, optically active 4-hydroxyalk-2-enoates (up to 91% ee) have been obtained in good yields. 相似文献
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Sigeru Torii Hideo Tanaka Norio Saitoh Takashi Siroi Michio Sasaoka Junzo Nokami 《Tetrahedron letters》1981,22(33):3193-3196
Chemoselective electrochlorination of the methyl group on the 3-methyl-3-butenoate moiety of thiazoline-azetidinone derivatives derived from penicillins G and V has been performed in a CH2Cl2-H2O-NaCl-H2SO4-(Pt or C electrodes) system by adjusting the amount of electricity passed as well as the concentration of Cl? in the media. 相似文献
305.
Impurity 51V nuclear relaxation time T1 in AuV Kondo alloys was measured in the temperature range 78–540 K, which includes the Kondo temperature TK of ~300 K. Considerable deviation from Korringa's relation was observed. 相似文献
306.
The photooxidation of chloral was studied by infrared spectroscopy under steady-state conditions with irradiation of a blackblue fluorescent lamp (300 nm < λ < 400 nm, λmax = 360 nm) at 296 ± 2 K. The products were hydrogen chloride, carbon monoxide, carbon dioxide, and phosgen. The kinetic results reveal that the reaction proceeds via chain reaction of the Cl atom: The results lead to the conclusion that mechanism (B) is confirmed to be more likely than mechanism (A), which was favored at one time by Heicklen for the mechanism of the oxidation of trichloromethyl radicals by oxygen molecules: The ratio of the initial rates of CO and CO2 formation gave k7/k6 = 4.23M?1, and the lower limit of reaction (5) was found to be 3.7 × 108M?1 sec?1. 相似文献
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Sulphate in sulphate ores, e.g., alunite, anglesite, barytes, chalcanthite, gypsum, manganese sulphate ore, is reduced to hydrogen sulphide by the hypophosphite-tin metal-CPA method, if a slight modification is made. Sulphide ores, e.g., galena, sphalerite, are quantitatively decomposed with CPA alone to give hydrogen sulphide. Suitable reducing agents must be used for the quantitative recovery of hydrogen sulphide from pyrite, nickel sulphide, cobalt sulphide and cadmium sulphide, or elemental sulphur is liberated. Iodide must be used in the decomposition of chalcopyrite; the copper sulphide is too stable to be decomposed by CPA alone. Molybdenite is not decomposed in CPA even if reducing agents are added. The pretreatment methods for the determination of sulphur in sulphur oxyacids and elemental sulphur have also been investigated. 相似文献