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991.
Satoh T Ashitaka T Orihara S Saimoto Y Konno M 《Journal of colloid and interface science》2001,234(1):19-23
The electrorheological response and structure growth of colloidal silica suspension was studied with in situ measurements of the shear stress, electric conductivity, and dielectric permittivity of the suspension. The measurements were carried out under steady and sweep shears after the application of an electric field of alternative current (100 Hz) using silica particles with a diameter of 630 nm and a water content of 4.5 wt%. The measurements of the conductivity enabled the detection of structure growth formed by particle aggregation and clarified that the development of the particle aggregation enlarged the dielectric permittivity and the shear stress. Hysteretic behavior observed in the electrorheological response was explained by considering structure growth of the particle aggregation. The correlation equation for the shear stress and the dielectric permittivity obtained in our previous work (1) was found to be applicable to the present results. Copyright 2001 Academic Press. 相似文献
992.
Minoru Kumakura Isao Kaetsu Mieko Suzuki Shoichi Adachi Kenichi Imagawawa 《Analytica chimica acta》1984
Immobilized anti-α-fetoprotein discs for enzyme immunoassay of α-fetoprotein were prepared by radiation polymerization of hydroxyethylmethacrylate at ?78°C. The activity (determined by absorbance at 492 nm) of the discs varied with monomer concentration and disc thickness, the optimum values being 200–400 g l?1 and 10–30 μm, respectively. The discs have a porous polymer matrix, are flexible, and can be dried and stored for long periods. The correlation coefficient for α-fetoprotein concentration determined in sera by radio immunoassay and by enzyme imminoassay with the discs was high (0.97). The recovery of α-fetoprotein added to serum was 99.0–1055. 相似文献
993.
Myelin figures were found to form at the main phase transition temperatures of several phospholipids for various ph values and Ca2+ concentrations. The optical observation of myelin figure formation provides a simple method of detecting the phase transition of phospholipids. 相似文献
994.
A peak has been observed in the magnetic susceptibility of the singlet ground state system PrNi2, indicating a magnetic ordering. The transition is believed to be of a mixed nuclear-electronic type. 相似文献
995.
Ataka K Giess F Knoll W Naumann R Haber-Pohlmeier S Richter B Heberle J 《Journal of the American Chemical Society》2004,126(49):16199-16206
A novel concept is introduced for the oriented incorporation of membrane proteins into solid supported lipid bilayers. Recombinant cytochrome c oxidase solubilized in detergent was immobilized on a chemically modified gold surface via the affinity of its histidine-tag to a nickel-chelating nitrilo-triacetic acid (NTA) surface. The oriented protein monolayer was reconstituted into the lipid environment by detergent substitution. The individual steps of the surface modification, including (1) chemical modification of the gold support, (2) adsorption of the protein, and (3) reconstitution of the lipid bilayer, were followed in situ by means of surface-enhanced infrared absorption spectroscopy (SEIRAS) and accompanied by normal-mode analysis. The high surface sensitivity of SEIRAS allows for the identification of each chemical reaction process within the monolayer at the molecular level. Finally, full functionality of the surface-tethered cytochrome c oxidase was demonstrated by cyclic voltammetry after binding of the natural electron donor cytochrome c. 相似文献
996.
The treatment of o-iodopropiolanilides (12), which were easily prepared from o-iodophenylisocyanate (11) and ethynylmagnesium bromide, with sodium hydrogen telluride resulted in the intramolecular ring closure of the presumed phenyltellurol intermediates (13) to a triple bond to give the 1,5-benzotellurazepin-4-ones (14) as the sole characterized products. The obtained amides (14) were easily converted into fully unsaturated lactim 4-methoxy-1,5-benzotellurazepines (18) by treatment with trimethyloxonium tetrafluoroborate. Decomposition by thermolysis of the 4-methoxyazepinenes (18) afforded the 4-methoxyquinolines (19) with extrusion of a tellurium atom. 相似文献
997.
We investigate the structure of vortex states in rotating two-component Bose-Einstein condensates with equal intracomponent but varying intercomponent-coupling constants. A phase diagram in the intercomponent-coupling versus rotation-frequency plane reveals rich equilibrium structures of vortex states. As the ratio of intercomponent to intracomponent couplings increases, the interlocked vortex lattices undergo phase transitions from triangular to square, to double-core lattices, and eventually develop interwoven "serpentine" vortex sheets with each component made up of chains of singly quantized vortices. 相似文献
998.
Nishimura Y Adachi H Satoh T Shitara E Nakamura H Kojima F Takeuchi T 《The Journal of organic chemistry》2000,65(16):4871-4882
An efficient and general synthetic route to all eight stereoisomeric D-glycono-delta-lactams has been developed. The strategy involves, as a key step, a stereodivergent delta-lactam formation with configurational retention or inversion at C-4 of a starting gamma-lactone to lead to two epimers of delta-lactam from one parent gamma-lactone. Conformations of eight glycono-delta-lactams were examined by X-ray crystallographic analysis and molecular modeling. Analyses of conformation and glycosidase-inhibition provide useful information for the design of new glycosidase inhibitors. 相似文献
999.
Yoshihiko Shoji Takao Asaka Hideki Dewa Hirohumi Hanaki Yoshinori Hisaoka Toshiaki Kobayashi Takahiro Matsubara Takayuki Mitsui Akihiko Mizuno Shinsuke Suzuki Tsutomu Taniuchi Hiromitsu Tomizawa Kenichi Yanagida 《Infrared Physics & Technology》2008,51(5):394-396
We have demonstrated the idea of circulating a short, intense linac bunch for some tens of turns in an isochronous ring. We compressed a bunch from the SPring-8 linac to a few picoseconds rms by means of an energy compression system and a beam transport line from the linac to NewSUBARU. The NewSUBARU storage ring was set to a quasi-isochronous condition and the bunch circulated for about 50 turns after injection while maintaining the short bunch length. At the same time, a pulse train of strong coherent synchrotron oscillation from the short bunch was observed. 相似文献
1000.
This paper reports on the afterglow mechanism and thermoluminescence (TL) of a red-emitting CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion upon irradiation by visible light (D65 lamp). In the TL glow curve of the CaS:Eu2+,Pr3+ phosphor, a TL peak was observed near 120 °C. The luminescence center of the CaS:Eu2+,Pr3+ phosphor was the Eu2+ ion and the trap depth of the CaS:Eu2+,Pr3+ phosphor with the cation vacancy (Trap 1) which formed by incorporation of the Pr3+ ion was 0.202 eV. A cation vacancy (Trap 2) was formed by incorporation of the Li+ ion in the CaS:Eu2+,Pr3+ phosphor. In the TL glow curve of the CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion, two TL peaks were observed near 120 and 200 °C. The TL luminance of the CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion increased with an increase in the initial Li/Ca atomic ratio. The two TL peaks moved to the high-temperature side with an increase in heating rate. The cation vacancy (Trap 2) calculated from the Hoogenstraaten method was 0.118 eV. The afterglow time of the CaS:Eu2+,Pr3+ phosphor with incorporated Li+ ion was prolonged by generation of a shallow trap. 相似文献