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981.
Inclusion crystals of 3,1'-bis-(4-fluorophenyl)-1'-hydroperoxy-3'-hydroxy-1',3'-dihydro-3H-[2,2']biindenyliden-1-one showed photochromic and photomagnetic properties in the solid state. 相似文献
982.
The first demonstration of photo-reversible Pb2+-complexation of an insoluble spiropyran-carrying copolymer in aqueous solutions is presented. 相似文献
983.
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987.
The double diffraction light intensity of two identical gratings placed parallel in the Fresnel region is sensitive to the lateral displacement ΔX, and is also affected by the air gap R between the gratings. In this note, the dependence of the double diffraction light intensity on ΔX and R for each order beam has been obtained directly by observing the intensity pattern on a screen. 相似文献
988.
Oxypyrrolnitrin: a metabolite of Pseudomonas 总被引:2,自引:0,他引:2
989.
T. Fukumoto A. Okamoto T. Hattori A. Mitsuishi T. Fukuda 《Solid State Communications》1975,17(4):427-431
The polariton modes of A1, B1 and B2 species in biaxial KNbO3 are observed by near forward Raman scattering. The oscillator strengths and dielectric constants along the principal axes are determined from the polariton dispersion. The mode assignments of each species are also discussed. 相似文献
990.
Keiichiro Adachi Mitsuhiro Hattori Yoichi Ishida 《Journal of Polymer Science.Polymer Physics》1977,15(4):693-701
Dielectric measurements, differential thermal analyses (DTA), and broad-line proton magnetic resonance (NMR) measurements are reported on the system poly(vinyl acetate)–toluene. Four dielectric relaxations were observed between 80 and 400°K. From proton NMR measurements on solutions in toluene and in deuterated toluene, the relaxation processes can be assigned, respectively, to segmental motion of poly(vinyl acetate), α; motion of side group, β′ rotation of toluene, β; local motions of poly(vinyl acetate) and toluene, γ, in order of appearance with decreasing temperature. Two stepwise changes in DTA traces have been observed and can be assigned as glass transition points TgI and TgII. Comparison of these glass transition points with temperatures at which dielectric relaxation times for the α and β processes are 100 sec, indicate that segmental motion of poly(vinyl acetate) and rotation of toluene are frozen-in at TgI and TgII, respectively. Activation plots for the α process conform to the Vogel–Tamman equation. In terms of the parameters A, B, and T0 of the equation, TgI can be represented by an expression of the form TgI ≈ T0 + B/(A + 3). In the range of concentration above 50% by weight, A and B are almost independent of concentration but T0 varies strongly. The nature of the secondary dispersions is also discussed. 相似文献