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961.
K. Sato S. Yamaji K. Harada S. Yoshida 《Zeitschrift für Physik A Hadrons and Nuclei》1979,290(2):149-156
Taking the relative distanceR and the deformationδ of each nucleus as the collective variables, we solve the two dimensional coupled dynamical equations of motion with friction in the framework of the linear response theory. In solving the equations of motion, we approximately replace the inertia tensor with the hydrodynamical one and use the modified liquid-drop one as the collective potential energy. As the frictional coefficients we use the microscopically calculated ones in the previous paper. The calculation is done for the reaction of28Si+20Ne, in which the incident energy of20Ne is 120 MeV. Results show that our microscopically calculated friction gives the large value of energy dissipation which amounts to the “completely damped” collision. Besides it, growths of the oblate deformation in the entrance channel and the prolate deformation in the exit channel are clearly seen. They give a large influence on the time development of the energy dissipation. We compare our calculated results with the experimental data for the reactions of 120 MeV20Ne with27Al. The agreement between them is found to be reasonably good. 相似文献
962.
Hiroyuki Yoshida Takushi Ito Akira Murata 《Fresenius' Journal of Analytical Chemistry》1990,338(6):738-740
Summary The acid dissociation constant of 4-methyl-6-acetyl-7-hydroxycoumarin, as determined by spectrophotometry was found to be Ka=9.77×10–9. Beryllium reacts with this reagent to form a water-insoluble complex that can be extracted into benzene. The maximum wavelengths of the excitation and emission spectra of the beryllium complex in benzene are 403 and 465 nm, respectively. Beryllium can be determined in the range 0.0050.1 g per 10 ml benzene when extracted from the solution at pH 7.57.8 into benzene. 相似文献
963.
Terashima K. Komaki H. Yoshida T. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1990,18(6):980-984
The authors have successfully developed a novel process for the deposition of multicomponent systems, namely radio-frequency (RF) plasma flash evaporation, in which powder mixtures of constituents are continuously injected into a RF plasma and are coevaporated and codeposited onto a substrate. The Y-Ba-Cu-O films prepared by this method showed excellent superconducting properties without postannealing; a deposition rate above several hundred nm/min was achieved. The film deposited on a MgO (100) substrate at 700°C reveals c -axis-oriented, polycrystalline orthorhombic oxygen-deficient perovskite showing a superconducting transition temperature of 87 K and a critical current density on the order of 1×106 A/cm2 at 77 K estimated from the magnetization. The conditions of plasmas during the deposition were measured by optical emission spectroscopy 相似文献
964.
S. Nasu H. Kitagawa M. Yoshida Y. Oda K. Ueda T. Kohara T. Shinjo K. Asayama F. E. Fujita 《Hyperfine Interactions》1990,55(1-4):1355-1362
57Fe Mössbauer measurements have been performed for Fe-doped YBa2 (Cu1-x Fex)3O7-v (x=0.005–0.10) superconducting oxides. Fe atoms mainly substitute at Cul chain sites and the fraction of Fe at Cu2 plane sites is discussed thermodynamically. The spin direction of Fe at Cu2 was determined to be normal to thec-axis using an oxygen deficient specimen having a strong texture along thec-axis. A magnetically broadened spectrum at 4.2 K for Fe at Cul is compared with a simulated one which takes the distribution of hyperfine fields into account. 相似文献
965.
Minoru Kumakura Masaru Yoshida Masaharu Asano Isao Kaetsu 《Applied biochemistry and biotechnology》1977,2(3):279-288
Immobilization of enzymes by a double entrapping method was investigated, α-Amylase was trapped by radiation-induced low temperature polymerization of 2-hydroxyethyl methacrylate after being absorbed by various inorganic additives. Drierite showed the most remarkable effect by increased enzymatic activity and decreased activity loss in batch enzyme reactions. Double entrapping of cellulase was tried by preparing an entangled mixture of enzyme and various natural polymers as additives and then polymerizing with the monomeric system at low temperatures. The composite, including enzyme-additive mixture prepared by coprecipitating and coevaporating methods, showed a considerable enhancing effect on enzymatic activity and durability in batch enzyme reactions. 相似文献
966.
In Pharbitis nil cotyledons, the lag phase of chlorophyll a (Chi a) accumulation which continues for about 2 h after the onset of continuous white light is eliminated by preirradiation with far-red light (FR) for 24 or 48 h. When the period of FR preirradiation is prolonged to 72 h or more, however, the lag phase is observed again (FR-induced lag phase) and the rate of Chi a accumulation during the rapid accumulation phase is lowered below the dark control level.
The application of exogenous 5-aminolevulinate (J-ALA) completely eliminates the FR-induced lag phase, but this treatment eliminates the normal lag phase in dark-grown cotyledons only partially (i.e. Chi a is accumulated but only slowly during the first few h). Application of a 5-ALA precursor, such as glycin + succinate. 2-ketoglutarate or glutamate, eliminates neither the FR-induced lag phase nor the normal lag phase.
A 24- or 48-h FR irradiation seems not only to enable the synthesis of 5-ALA but also to make the other regulatory factors favourable for Chi accumulation. When the period of FR irradiation is prolonged to 72 h or more, the ability to synthesize 5-ALA may be lost. 相似文献
The application of exogenous 5-aminolevulinate (J-ALA) completely eliminates the FR-induced lag phase, but this treatment eliminates the normal lag phase in dark-grown cotyledons only partially (i.e. Chi a is accumulated but only slowly during the first few h). Application of a 5-ALA precursor, such as glycin + succinate. 2-ketoglutarate or glutamate, eliminates neither the FR-induced lag phase nor the normal lag phase.
A 24- or 48-h FR irradiation seems not only to enable the synthesis of 5-ALA but also to make the other regulatory factors favourable for Chi accumulation. When the period of FR irradiation is prolonged to 72 h or more, the ability to synthesize 5-ALA may be lost. 相似文献
967.
968.
969.
Kohei Tamao Masayuki Mishima Jun-ichi Yoshida Masataka Takahashi Neyoshi Ishida Makoto Kumada 《Journal of organometallic chemistry》1982,225(1):151-162
The reactions of potassium 5-norbornen-2-ylpentafluorosilicate (I) and 5-norbornen-2-yltrimethylsilane (II) with NBS were examined. The former reaction gave 3-nortricyclyl bromide (IV) as the only detectable product, arising from the carbon—silicon bond cleavage. The latter reaction, however, gave 3-bromo-1-nortricyclyltrimethylsilane (V) as the major product, resulting from cleavage of the carbon—hydrogen bond α to silicon, together with IV and an unidentified product. GLC-monitoring of the reactions showed the higher reactivity of the norbornenyl derivative having the leaving group in theendo position irrespective of whether the leaving group is SiF5 or H. Since no inhibition was observed by the addition of hydroquinone in the dark, the reactions have been regarded as homoallylic electrophilic substitutions. A concerted mechanism seems to be consistent with the experimental data. Cleavage of 1-nortricyclyltrimethylsilane by iodine monochloride to give 1-iodonortricyclene has also been studied. 相似文献
970.
Kiyoshi Tanabe Hiroki Haraguchi Keiichiro Fuwa 《Spectrochimica Acta Part B: Atomic Spectroscopy》1981,36(7):633-639
An atmospheric pressure helium microwave-induced plasma (MIP) was combined with a gas chromatograph (GC). and used as an element-selective detector for GC. The detection limits, dynamic ranges and selectivities were obtained for H, C, F, Cl, Br, I and S. Such data for nitrogen and oxygen could not be obtained because of the interference from air which was entrained into the system through the leakages of the tubing and the valve system. The detection limits and dynamic ranges for all the elements investigated were in a range between 1.8 and 39pgs?1 and between 1.6 × 103 and 1.1 × 105, respectively. Furthermore, the relative sensitivities of C, H, Cl and Br for various compounds were examined. In the cases of carbon and hydrogen, the relative sensitivities were not the same for different compounds containing oxygen and nitrogen. This result may be explained by the incomplete decomposition of such compounds due to the low microwave power (75 W) applied in the present system. 相似文献