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951.
952.
Naoki Inamoto Shozo Masuda Katsumi Tokumaru Masayuki Yoshida Youko Tamura Kazuo Tori 《Tetrahedron letters》1975,16(43):3697-3700
953.
Reaction of ketone hydrazones with disulfur dichloride in the presence of triethylamine in benzene at 0 °C - room temperature afforded the corresponding thiones in a moderate to high yield, probably via thioxothioketone (R2C=S=S) intermediate. 相似文献
954.
Kazuhiko Ishihara Naoki Negishi Isao Shinohara 《Journal of polymer science. Part A, Polymer chemistry》1981,19(12):3039-3046
Water-soluble polymeric azodyes containing an azobenzene moiety in their side chain, p-phenylazoacrylanilide (PAAn)–acrylamide (AAm) copolymers, were synthesized and the adsorption-desorption behavior of sodium dodecyl sulfate (SDS) onto these copolymers in water was investigated by means of conductivity measurements, with attention to the hydrophobicity of the copolymer. The conductivity of the PAAn-AAm copolymer/SDS complex aqueous solution decreased with increasing PAAn composition in the copolymer. This result indicates that the SDS molecules adsorbed onto the copolymer. The adsorption state of SDS molecules on the copolymer was considered to take a micellelike form. When the hydrophobicity of the PAAn-AAm copolymer was decreased by means of the photoisomerization of an azodye moiety, the conductivity of the PAAn-AAm copolymer/SDS aqueous solution increased. This phenomenon can be explained as a result of desorption of SDS molecules from the copolymer. When the light source was cut off, the conductivity took on its original value. This indicated that SDS was desorbed by the photochemical trans to cis and adsorbed by cis to trans isomerization of the PAAn moiety. 相似文献
955.
Fiberscopic video laryngoscopy was performed on five professional singers to determine the presence or absence of aryepiglottic narrowing as a function of voice quality. Each sang “Happy Birthday” and parts of the “Star Spangled Banner” in six different voice qualities: speech, falsetto, sob (a low larynx with a vocal tract expanded by relaxing the middle constrictors), twang, belting, and opera. Several features were found to be common among the subjects and related to specific qualities. Aryepiglottic constriction was present in all singers in twang, belting, and opera qualities. Spectrographic analysis related the constriction to the presence of the “singer's formant.” The presence of this type of constrictive behavior will require further research to ascertain the possible benefits to those for whom a louder voice is essential and to understand the relationship of this constrictive maneuver to the natural closure functions of the larynx. 相似文献
956.
H. Fuchi K. Hoshino S. Kuramata K. Niu H. Shibuya S. Tasaka Y. Yanagisawa N. Ushida Y. Maeda H. Kimura 《Physics letters. [Part B]》1979,85(1):135-141
The second evidence of a pair decay of charmed particles has been obtained in an emulsion chamber exposed to protons. The life time and production cross section of the charmed particles have been evaluated as several times 10?13 s and several tens of microbarns. 相似文献
957.
Masaaki Yoshifuji Kozo Toyota Katsuhiro Shibayama Naoki Inamoto 《Tetrahedron letters》1984,25(17):1809-1812
Very stable iminomethylenephosphine (3) and ethenylidenephosphine (4) were obtained by steric protection with the 2,4,6-tri-tertbutylphenyl group and some of the spectroscopic data are described. 相似文献
958.
959.
Frontispiece: Whole‐Cell Biotransformation of Benzene to Phenol Catalysed by Intracellular Cytochrome P450BM3 Activated by External Additives
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960.
Yuzuki Yamamoto Naoki Mori Hidenori Watanabe Hirosato Takikawa 《Tetrahedron letters》2018,59(38):3503-3505
Pseudohygrophorones A12 and B12 are cyclohexenone derivatives isolated from Hygrophorus abieticola (Basidiomycete) as anti-phytopathogenic compounds. In this study, the first synthesis of (±)-pseudohygrophorones A12 is reported, utilizing Michael–aldol cascade reaction for constructing the 3,3-dimethyl-2,4-dioxabicyclo[3.1.1]nonan-9-one skeleton and the diastereoselective addition of alkyllithium to the one-side blocked ketone as the key steps. 相似文献