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581.
Optical phase conjugation has been observed from non-local gratings generated in a photorefractive mesogenic composite consisting of a low-molar-mass nematic mixture, a functionalized copolymer and a photoconductive sensitizer. The degenerate four-wave mixing experiment enabled measurements of phase conjugate reflectance as a function of the intensity ratio of the forward and backward pump beams. The characteristics were strongly dependent on the spatial phase shift; these results are quantitatively explained by the coupled wave theory in relation to non-local gratings.  相似文献   
582.
We proposed to combine an ultra-micro flow analysis instrument using the fused-silica capillary and the CL detector. The CL reaction of luminol and hydrogen peroxide was adopted and the batch-type CL detection cell was used. Luminol and isoluminol-labeled protein as a model were sensitively and reproducibly detected with very small amounts of quantitative reagents. The analyses were repeated at least 100 times without any treatments such as washing capillaries or exchanging the hydrogen peroxide solution. The present system successfully promoted the miniaturization, simplification, and sensitization of the analytical system.  相似文献   
583.
In this paper, we show a procedure to realize a statistical manifold, which is -conformally equivalent to a manifold with an -transitively flat connection, as a statistical submanifold. Received 29 December 1999.  相似文献   
584.
CERN experiment NA44 measures pion and kaon distributions atpT=0–320 MeV/c at midrapidity in p+A and A+A collisions at 450 and 200A GeV/c, respectively. Pion production from p+Pb and A+A is slightly enhanced at lowpT relative to p+Be, but less than observed at target rapidity. The lowpT behavior can be understood in the context of the RQMD model as arising from baryonic resonance decays.  相似文献   
585.
CERN experiment NA44 measures pion and kaon distributions at p T = 0–320 MeV/c at midrapidity in p+A and A+A collisions at 450 and 200A GeV/c, respectively. Pion production from p+Pb and A+A is slightly enhanced at low p T relative to p+Be, but less than observed at target rapidity. The low p T behavior can be understood in the context of the RQMD model as arising from baryonic resonance decays.  相似文献   
586.
587.
The oxidation kinetics of malic acid by vanadium(V) in aqueous sulphuric acid was investigated at 303 K by monitoring the appearance of vanadium(IV) at 760 nm. The reaction showed first-order behavior with respect to vanadium(V), malic acid, and hydrogen ion concentration, respectively, regardless of the ionic strength. The reaction rate is enhanced by an increase in ionic strength and a decrease of the dielectric constant of the medium by addition of methanol. The activation parameters were estimated by varying the temperature in the range of 293 K to 313 K to 313 K. An oxidation mechanism is proposed, involving different vanadium(V) species produced in the presence of sulphuric acid. © 1995 John Wiley & Sons, Inc.  相似文献   
588.
589.
Conclusions A method was developed for the preparation of acetoxyacetaldehyde (60% yield) by the hydrolysis of 1-ethoxy-1, 2-diacetoxyethane. Acetoxyacetaldehyde oligomerizes even at room temperature.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1630–1631, July, 1976.  相似文献   
590.
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