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81.
Norio Kobayashi Tamotsu Fujisawa 《Journal of polymer science. Part A, Polymer chemistry》1972,10(9):2591-2600
Poly(sulfenyl thiocarbonates) have been prepared for the first time by the stepwise condensation of chlorocarbonylsulfenyl chloride with diols and dithiols. The polymers were obtained in high yield. Generally they were crystalline solids and were soluble in chlorinated hydrocarbons. On treatment with benzyl mercaptan in the presence of triethylamine, the polymers afforded a diol, carbonyl sulfide, and a disulfide compound. This reaction was extended to the preparation of alternating copolydisulfides. 相似文献
82.
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84.
Norio Hayakawa 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1970,21(5):685-689
Zusammenfassung In der vorliegenden Arbeit wird das Variationsproblem, welches die Schranken für den Durchfluss in turbulenter Strömung auf einer geneigten Platte bestimmt, nach Busse [2] abgeleitet. Es wird die symmetrische Natur der Lösung des Variationsproblems für die ebene Poiseuille-Strömung geprüft. Dies zeigt einerseits Ähnlichkeit und andrerseits Unterschiede zwischen dem Problem der ebenen Poiseuille-Strömung und der Strömung auf einer geneigten Platte. 相似文献
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86.
Sadamoto R Niikura K Ueda T Monde K Fukuhara N Nishimura S 《Journal of the American Chemical Society》2004,126(12):3755-3761
UDP-MurNAc-pentapeptide derivative bacterial cell-wall precursors were synthesized as effective tools for surface display on living bacteria. Lactobacilli were incubated in the ketone-modified precursor-containing medium, and the ketone moiety was displayed on the bacterial surface through cell-wall biosynthesis. Oligomannose was coupled with the ketone moiety on the bacterial surface via a aminooxyl linker, thereby displaying this oligosaccharide on the surface of the bacteria. The increase in the adhesion of the sugar-displaying bacteria onto a concanavalin A-attached film compared to that of native bacteria was confirmed by microscopic observation and surface plasmon resonance measurement. The incorporation of the artificial cell-wall precursors was enhanced when incubated with fosfomycin, an inhibitor of cell-wall precursor biosynthesis. 相似文献
87.
We propose a color vision model that can be used to predict color appearance in mesopic vision as well as photopic and scotopic vision. It is based on a two-stage model which consists of the cone and opponent stages and it assumes rod intrusion at the opponent stage. The model has the following features to describe the color appearance in mesopic vision. First, it includes a gradual and nonlinear shift in spectral luminous efficiency from V (LD) to V (LD) to cope with the spectral sensitivity difference between photopic and scotopic vision and the nonlinearity of rod influence on the luminance channel. Second, the model assumes decrease of the chromatic component with decreasing illuminance to explain the reduction of saturation at low illuminance levels. Third, it assumes that red/green and yellow/blue components change with illuminance levels independently, thus explaining hue shifts with decreasing illuminance. We applied the model for color appearance simulation of natural scenes in a mesopic visual environment. 相似文献
88.
Norihiro?SadatoEmail author Hiroki?Yamada Tomohisa?Okada Masaki?Yoshida Takehiro?Hasegawa Ken-Ichi?Matsuki Yoshiharu?Yonekura Harumi?Itoh 《BMC neuroscience》2004,5(1):56
Background
Sign-language comprehension activates the auditory cortex in deaf subjects. It is not known whether this functional plasticity in the temporal cortex is age dependent. We conducted functional magnetic-resonance imaging in six deaf signers who lost their hearing before the age of 2 years, five deaf signers who were >5 years of age at the time of hearing loss and six signers with normal hearing. The task was sentence comprehension in Japanese sign language. 相似文献89.
Kitajima M Hashimoto K Sandoval M Aimi N Takayama H 《Chemical & pharmaceutical bulletin》2004,52(10):1258-1261
A new oleanan-type triterpene and three new cincholic acid glycosides were isolated from Peruvian "Una de Gato" (Cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis. 相似文献
90.
Takayama H Ishikawa H Kitajima M Aimi N Aji BM 《Chemical & pharmaceutical bulletin》2004,52(3):359-361
A new yohimbine-type indole alkaloid (1). was isolated from the stem bark of Mitragyna africanus (WILLD.) collected in Nigeria, along with known seven Corynanthe-type oxindole alkaloids, two secoiridoids, three lignans, and a quinovic acid derivative. Their structures were elucidated by spectroscopic analyses. 相似文献