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571.
Masaji Shimadzu Nobuko Ishikawa Katsumi Yamamoto Akira Tanaka 《Journal of heterocyclic chemistry》1986,23(4):1179-1182
Methyl 5-alkoxy-2-furancarboxylates, methyl 5-alkylthio-2-furancarboxylates and methyl 5-phenylthio-2-furancarboxylate were prepared by nucleophilic substitution of methyl 5-nitro-2-furancarboxylates. Also, 5-phenoxyfuran-2-nitriles and 5-phenylthiofuran-2-nitriles were prepared. 相似文献
572.
573.
H. Enyo S. Sasaki T. Nagae K. Tokushuku M. Sano M. Sekimoto J. Chiba K. Ichimaru T. Mori T. Katsumi H. Yokota R. Chiba K. Nakai 《Physics letters. [Part B]》1985,159(1):1-4
Spectra of protons and pions emitted in the target-rapidity region in hadron-nucleus reactions at 3 and 4 were observed in wide momentum- and angular-acceptance measurements. Fitting to the data with the two-moving-source model well reproduced experimental proton spectra with the slope parameters of 50–60 MeV for one component and 110–125 MeV for another. The slope parameters for pions were 120–165 MeV, larger than those for protons. Energy depositions of GeV particles were estimated by integrating energies carried away through the particle production 相似文献
574.
575.
576.
577.
Monocyclic β-lactams () were converted into 4-cyano derivative (C1-unit introduction) under two phase reaction conditions. The cyano group in was successively transformed into and , which are thought to be important precursors for the carbapenem synthesis. 相似文献
578.
Katsumi Matsuura Masamitsu Hirota Keizo Shimada Mamoru Mimuro 《Photochemistry and photobiology》1993,57(1):92-97
Spectral forms of bacteriochlorophyll (Bchl) in chlorosomes were analyzed by linear dichroism, circular dichroism (CD), and deconvolution of these spectra. Isolated chlorosomes were embedded in polyacrylamide gels and compressed unidirectionally (along the x-axis) while allowing the gel to stretch in another direction (along the z-axis). The chlorosomes were aligned three-dimensionally due to their flat oblong shape; the longest axis was presumed to parallel the z-axis, its shortest axis was presumed to parallel the x-axis, and the intermediate-length axis was presumed to parallel the y-axis. Degrees of polarization (AI? A1)/(AI+ A1) of Bchl c and a measured from the y-axis with linearly polarized light were significantly different from those measured from the x-axis. Deconvolution of spectra into components revealed the presence of two major forms of Bchl c with peaks at 744 nm and 727 nm. The degrees of polarization of the 744 and 727 nm spectral forms were 0.76 and 0.59 from the y-axis and 0.48 and 0.39 from the x-axis, respectively. The degrees of polarization of Bchl a794 were –0.21 from the y-axis and 0.12 from the x-axis. These values indicate that the direction of the Qy transition moment of Bchl c744 is almost completely parallel to the longest axis of chlorosomes and that of Bchl c727 is also nearly, but slightly less so, parallel to the longest axis of the chlorosomes. The Qy transition moment of the baseplate Bchl a peak at 794 nm is nearly perpendicular to the longest axis and parallel to the shortest axis: that is, it is perpendicular to the associated membrane plane in the cell. These alignments of Bchl transition moments in chlorosomes were lost after suspending the chlorosomes in a solution saturated with 1-hexanol accompanying a shift in the peak position from 742 nm to 670 nm. The alignment recovered after the hexanol concentration was decreased. The presence of two major spectral forms of Bchl c was supported by the deconvolution of CD spectra and absorption spectra. 相似文献
579.
580.
Katsumi Sugita Yoshiwo Okamoto Matsuo Sekine 《International Journal of Theoretical Physics》1996,35(12):2439-2442
Based on an infinite sublayer quark model, we determine the fraction of nucleon spin carried by subquarks. 相似文献