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91.
Dynamics of the boundaries of photoinduced nuclei in electron–phonon systems is theoretically studied. By regarding the spatial distribution of the excited electronic state population as a geometric pattern, we applied the multifractal analysis to it and calculated the temporal behavior of the fractal dimension f(α) as a function of the Lipschitz–Hölder exponent α, which is an appropriate method for understanding the cooperative relaxation process of photoexcited states. We found that the incubation period observed in various types of photoinduced cooperative phenomena corresponds to the formation of embryonic nuclei which is driven by nonadiabatic/adiabatic transition between electronic states during the relaxation of the Franck–Condon state. 相似文献
92.
93.
We point out that SO(2N(c)) gauge theory with N(f) fundamental Dirac fermions does not have a sign problem at finite baryon number chemical potential μ(B). One can thus use lattice Monte Carlo simulations to study this theory at finite density. The absence of a sign problem in the SO(2N(c)) theory is particularly interesting because a wide class of observables in the SO(2N(c)) theory coincide with observables in QCD in the large N(c) limit, as we show using the technique of large N(c) orbifold equivalence. We argue that the orbifold equivalence between the two theories continues to hold at finite μ(B) provided one adds appropriate deformation terms to the SO(2N(c)) theory. This opens up the prospect of learning about QCD at finite μ(B) using lattice studies of the SO(2N(c)) theory. 相似文献
94.
95.
Yoshifumi Hanada Teizi Tanizaki Minoru Koga Hiroaki Shiraishi Mitsuyuki Soma 《Analytical sciences》2002,18(4):441-444
Liquid chromatography/mass spectrometry (LC/MS) has been applied to analyze N,N'-ethylenebisdithiocarbamate fungicides (EBDCs: manzeb, maneb and zineb) in environmental water samples. The EBDCs that are zinc and/or manganese salts are transformed into readily water-soluble sodium salts by adding an alkaline EDTA solution. The N,N'-ethylenebisdithiocarbamate anion is extracted into chloroform-hexane (3:1) as an ion pair with tetrabutylammonium, and then S-alkylated with methyl iodide. The extraction and derivatization are carried out at room temperature. The derivatized ethylenebisdithiocarbamic acid dimethyl ester is introduced into an LC/MS equipped with a negative ion electrospray ionization interface. Identification of the compound is performed with the specific quasi-molecular ion, and the quantitative analyses are carried out using the peak areas. The average recoveries and coefficients of variation of EBDCs at sub-ppb level are 79.1% and 29.3% (n = 6), respectively. The limit of detection based on standard deviation of 0.043 microg/L for manzeb is achieved. 相似文献
96.
Hideo Nemoto Hiroshi Kurobe Keiichiro Fukumoto Tetsuji Kametani 《Tetrahedron letters》1984,25(41):4669-4672
Stereocontrolled synthesis of (?)-de-AB-8-oxa-cholest-14-en-9-one (2) as an optically active form was achieved starting from the methylene ketone (7). This work constitutes a formal synthesis of de-AB-cholestan (1). 相似文献
97.
The tetracyclic compounds ~3 and ~4 corresponding to A-homograyanotoxane system were synthesised by a thermolysis of the benzocyclobutene ~8, followed by a Wagner-Meerwein rearrangement of the kaurane type of compounds ~15 and ~16. 相似文献
98.
NMR-ON measurements have been performed for60CoFe−Si. The samples of Fe−Si (6 at. %) single crystal dish with the (110) surface were used. Rosonance measurements have been carried
out with the magnetization direction along the <100> and the <111> axes. Five prominent resonances were found at 166, 162,
151, 147 and 135 Mllz. The resonance at 166 Mllz has been known to be due to60Co without neighbourt Si atoms. The resonances at 151 and 135 Mllz are due to60Co nuclei with one and two Si atom(s) in the 1st neighbour site, respectively. The resonances at 162 and 147 Mllz would be
due to the contribution of the 3rd <111> and the <100> magnetization axes, the differences of the resonance width have been
qualitatively explained using the dipolar field. 相似文献
99.
Isoniazid in solutions of tablets was separated by thin-layer chromatography (TLC). The portion of the precoated plate carrying the isoniazid spot was cut out and the coating was scraped off into water. The isoniazid was quantified in the solution, without separation of suspended adsorbent, by second-derivative spectrophotometry, which eliminated the background in the zero-order spectra. Relative standard deviations (n = 5) were <1%. Results obtained for commercial tablets were in good agreement with those given by a liquid-chromatographic method. 相似文献
100.
Soon-Ku Hong Takashi Hanada Yefen Chen Hang-Ju Ko Takafumi Yao Daisuke Imai Kiyoaki Araki Makoto Shinohara 《Applied Surface Science》2002,190(1-4):491-497
Control of polarity of heteroepitaxial ZnO films has been examined by interface engineering. ZnO films were grown by plasma-assisted molecular beam epitaxy on Ga-polar GaN template and c-plane sapphire substrates. Polarity of all the samples is determined by coaxial impact collision ion scattering spectroscopy. Zn- and O-polar ZnO films have successfully grown by Zn- and O-plasma pre-exposures on Ga-polar GaN templates prior to ZnO growth. High-resolution transmission electron microscopy revealed formation of a single-crystalline monoclinic Ga2O3 interface layer by O-plasma pre-exposure on Ga-polar GaN templates, while no interface layer was observed for Zn pre-exposed ZnO films. The polarity of ZnO films grown under oxygen ambient on c-plane sapphire with MgO buffer is revealed as O-polar. Fabrication of polarity inverted ZnO heterostructure has been studied: polarity of ZnO films on Ga-polar GaN templates was changed from Zn-polar to O-polar by inserting a MgO layer. High-resolution transmission electron microscopy revealed atomically flat interfaces at both lower and upper ZnO/MgO interfaces and no inversion domain boundaries were detected in the upper ZnO layer. 相似文献