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581.
582.
Hiroko Seki Yoshihisa Sei Kazuaki Shikii Sakurako Shimotakahara Hiroaki Utsumi Kentaro Yamaguchi Mitsuru Tashiro 《Analytical sciences》2004,20(10):1467-1470
A difference diffusion-based NMR technique and cold-spray ionization mass spectrometry were employed as a solution-based approach for identifying a ligand binding with a protein receptor. The difference diffusion-based NMR technique, called difference NOE-pumping, can directly detect the ligand interacting with a protein receptor. This technique uses a simple pulse sequence and the diffusion filter can easily be optimized. The cold-spray ionization mass spectrometry (CSI-MS), a variant of electrospray ionization mass spectrometry (ESI-MS) operating at low temperature, has been applied to detect the ligand-receptor complex. The efficiency of these techniques for identifying binding ligands is demonstrated with the human serum albumin (HSA)-drug system. 相似文献
583.
Yoshihisa Naijo Eita Fujisaki Makoto Tsunoda Toyohide Tanaka Norihisa Kobayashi 《先进技术聚合物》2003,14(9):653-657
Polypeptide having carbazolyl groups (poly(γ-[2-(9-carbazolyl)ethyl]-L -glutamate) (PCLG)) was synthesized in order to prepare a lyotropic liquid crystalline cell with higher mobility. This liquid crystal was revealed to show d.c. electric-field induced scattering behavior, in which the transparent cell became scattered after applying d.c. bias voltage. This behavior was enhanced by adding small amounts of 2,4,7-trinitrofluorenone (TNF) which is known to form charge transfer complex with carbazole. The transmittance varied from 90 to 20% under d.c. bias application. More than 150 turn-on and off cycles were achieved in this cell without serious degradation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
584.
585.
Principles and development of spatial filtering velocimetry 总被引:1,自引:0,他引:1
As one of the interesting optical techniques for measurements of the velocity, the spatial-filtering method is treated briefly in this review. The basic theory of the method is examined by analyzing the filtering characteristics of a spatial filter using the power spectral density function. The signal analyses are summarized as one of the techniques used in the spatial filtering method. Various configurations of the spatial filtering velocimeter are classified into typical four groups and outlined according to a variety of spatial filters employed in the velocimeters. 相似文献
586.
Nine spiroborate complexes (7–15) were analyzed by NMR and MS spectroscopy and the characteristic spectra and fragmentation patterns are reported. On the basis of these results, the structure of Meulenhoff's free acid is re-investigated. 相似文献
587.
Yoshihisa Okamoto Hiroko Amemiya Toshio Kinoshita Michiko Shirai Yoshio Matsumoto 《Polyhedron》1985,4(4):629-632
Reaction of 5,6-diamino-1,3-dimethyluracil (DDU) with iron(III) ion gave a fine blue colouration due to the formation of Fe[(DDU—H)3]·2HClO4. An oxidation product (7), C12H12N6O4, was also isolated from the reaction mixture. 相似文献
588.
The reaction of diphenylketene with terminal acetylenes catalyzed by tetrakis-(triphenylphosphine)palladium gave disubstituted acetylenes in high yields. 相似文献
589.
Yoshihisa Kurasawa Muneto Muramatsu Kaoru Yamazaki Setsuko Tajima Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1986,23(4):1245-1248
3-(α-Chlorophenylhydrazono-1,3,4-oxadiazol-2-ylmethyl)-2-oxo-1,2-dihydroquinoxalines 4a-d and 3-(α-chlorophenylhydrazono)methoxycarbonylmethyl-2-oxo-1,2-dihydroquinoxalines 5a-c have been clarified to exhibit the characteristic tautomeric equilibria between the hydrazone imine form C and the diazenyl enamine form D with a long-range prototropy by means of the pmr and 13C-nmr spectroscopies. 相似文献
590.
The present work reports an attempt to elucidate a stereoselective energy-transfer system by immobilizing a chiral metal complex on a clay surface. The metal complex used was [Ru(bpy)2L(i)]2+ with L1 = bpy (2,2'-bipyridine), L2 = 4,4'-diundecyl-2,2'-bipyridine, and L3 = 5,5'-diundecyl-2,2'-bipyridine. The adsorption structure of [Ru(bpy)2L(i)]2+ was studied by means of electric dichroism measurements on an aqueous dispersion of a colloidal clay. It was found that the molecular orientation of the adsorbed Ru(II) complex was affected remarkably by the positions of the alkyl chains on the bpy ligand; that is, the angle of the 3-fold or pseudo-3-fold symmetry axis of the Ru(II) complex with respect to the surface normal was obtained to be 24 degrees, 30 degrees, and 52 degrees for i = 1, 2, and 3, respectively. The efficiency of the energy-transfer was determined by photoluminescence quenching measurements between the adsorbed Ru(II) complex and [Ru(acac)3] (acac = acetylacetonate) in solution. As a result, stereoselectivity appeared most for the case of [Ru(bpy)2L3]2+ in which its two helically twisted bpy ligands were projected in an outward direction. 相似文献