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951.
952.
A significant temperature effect on the new photochemical reactions of 9-α-bromopropionylanthracene has been noted. In comparison to the temperature effect on the fluorescence intensity of 9-propionylanthracene, it was suggested that the rotation of the carbonyl group on photo-excitation might operate as an enhancing factor in the intersystem crossing process. 相似文献
953.
T. Shimada Y. Kato Y. Shiraki K.F. Komatsubara 《Journal of Physics and Chemistry of Solids》1976,37(3):305-313
Two types of non-crystalline states (“disordered” and “amorphous”) of GaP were produced by using ion implantation and post annealing. A structural-phase-transition-like annealing behaviour from the “disordered” state to the “amorphous” state was observed.The ion dose dependence and the annealing behaviour of the atomic structure of GaP implanted with 200 keV ? N+ ions were studied by using electron diffraction, backscattering and volume change measurements. The electronic structure was also investigated by measuring optical absorption and electrical conductivity.The implanted layer gradually loses the crystalline order with the increase of the nitrogen dose.The optical absorption coefficient α and electric conductivity σ of GaP crystals implanted with 200 keV?N+ ions of 1 × 1016 cm?2 were expressed as αhν = C(hν ? E0)n and log , respectively. Moreover, the volume of the implanted layer increased about three percent and the electron diffraction pattern was diffused halo whose intensity monotonically decreases along the radial direction. These results indicate that the as-implanted layer has neither a long range order nor a short range order (“disordered state”).In the sample implanted at 1 × 1016 cm?2, a structural phase-transition-like annealing stage was observed at around 400°C. That is, the optical absorption coefficient α abruptly fell off from 6 × 104 to 7 × 103 cm?1 and the volume of the implanted layer decreased about 2% within an increase of less than 10 degrees in the anneal temperature. Moreover, the short range order of the lattice structure appeared in the electron diffraction pattern. According to the backscattering experiment, the heavily implanted GaP was still in the non-crystalline state even after annealing.These facts lead us to believe that heavily implanted GaP, followed by annealing at around 400°C, is in the “amorphous” state, although as-implanted Gap is not in the “amorphous” state but in the “disordered” state. 相似文献
954.
Human blood group substance of the ABO system was immobilized in a mebrane matrix. The membrane-bound blood group substance retained its binding ability against the corresponding antibody (agglutinin) in serum. The transmembrane potential changed drastically with the agglutination of the membrane-bound blood group substance. Electrochemical typing of blood was performed with sera, using a pair of membranes with immobilized A- and B-type blood group substances. The blood type was determined by measuring the transmembrane potential across these membranes before and after the agglutination reaction. A possible re-use of the membrane-bound blood group substance by treatment with galactose is discussed. 相似文献
955.
956.
A. Nishiwaki S. Hattori Y. Kato Y. Hiraiwa T. Hiramatu H. Hoshikawa M. Katayama 《Optics & Laser Technology》1979,11(1):37-44
The optimum configuration of a total-internal-reflection type laser light modulator with surface interdigital electrodes has been obtained. The final specifications of the modulator were an effective half wavelenght voltage of 11.5 V, a capacitance between electrodes of 9.1 pF, and a modulation bandwidth of 400 MHz at 50 Ω load impedance. This corresponds to a remarkable safety factor of 1.7. Some effective means of eliminating harmful resonances due to acoustic waves excited in the electro-optic crystals by the interdigital electrodes were found. A practical optical communication system for transmitting catv signals in the open-air has been built and tested in the field using the modulator. In the system cross modulation and intermodulation between channels were found to be sufficiently small. 相似文献
957.
Satoshi Ikeda 《Reports on Mathematical Physics》1980,18(1):103-110
In this paper, the concept of “nonlocality”, which is carried by the internal variable (ω) ascribed to each point (x), is first investigated generally in connection with the concept of “unified” gauge field. Next, as a typical example, a Finslerian “nonlocal” field is considered, which is obtained by taking for ω a vector (ξ), and two examples are proposed: one is a unified field with Randers metric and the other is a micro-gravitational field endowed with space-time fluctuation. 相似文献
958.
959.
960.