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931.
J. Scott Carter Seiichi Kamada Masahico Saito 《Proceedings of the American Mathematical Society》2000,128(12):3761-3771
A generic projection of a knotted oriented surface in 4-space divides -space into regions. The number of times (counted with sign) that a path from infinity to a given region intersects the projected surface is called the Alexander numbering of the region. The Alexander numbering is extended to branch and triple points of the projections. A formula that relates these indices is presented.
932.
Oikawa M Saito T Takahisa K Suga Y Kino K Nakagawa T Tohei T Abe K Ueno H 《Physical review letters》2000,84(11):2338-2341
Out of plane measurements of the angular correlations for the 12C(e, e(')n) reaction have been performed for the first time in the giant resonance region. The cross sections were directly separated into the longitudinal and transverse, longitudinal-transverse, and transverse-transverse components. The cross section at the peak of the giant resonance ( omega = 22.5 MeV) has been found to be almost all longitudinal. It was reproduced by the multipole expansion with E0 and E2 components besides E1. The longitudinal-transverse component might have a maximum around 24 MeV. The transverse-transverse component is very small over the giant resonance. 相似文献
933.
We derive new QCD sum rules for the axial coupling constants by considering the correlation functions of axial-vector currents in a one-nucleon state. The QCD sum rules tell us that the axial coupling constants are expressed by nucleon matrix elements of quark-gluon composite operators which are related to the sigma terms and the moments of parton distributions. The results for the isovector axial coupling constants and the eighth component of the SU(3)(f) octet are in good agreement with experiment. 相似文献
934.
Rao AM Jorio A Pimenta MA Dantas MS Saito R Dresselhaus G Dresselhaus MS 《Physical review letters》2000,84(8):1820-1823
Polarized Raman spectra of high purity aligned arrays of multiwalled carbon nanotubes, prepared on silica substrates from the thermal decomposition of a ferrocene-xylene mixture, show a strong dependence of the graphitelike G band and the disorder-induced D band on the polarization geometry employed in the experiments. The experimental G-band intensity exhibits a minimum at straight theta(m) = 55 degrees in the VV configuration, in good agreement with theoretical predictions of a characteristic minimum at 54.7 degrees for A(1g) modes in single wall nanotubes, where straight theta(m) denotes the angle between the polarization direction and the nanotube axis. 相似文献
935.
936.
Eizi Hirota Yasuki Endo Shuji Saito J.L. Duncan 《Journal of Molecular Spectroscopy》1981,89(2):285-295
The microwave spectra of CH3CHD2 in the first excited torsional state and of CH3CH2D and CD3CH2D in the ground states have been observed by a source-modulation spectrometer and analyzed to determine the two potential constants, V3 and V6, simultaneously and also to assess the isotopic effects on the potential function. The results obtained for C2H6 are V3 = 2.882 ± 0.010 and V6 = 0.020 ± 0.010 kcal/mole. The staggered conformation in ethane was established by observing microwave spectra of gauche CH2DCH2D. The rz structure of ethane was recalculated by adding precise rotational constants obtained in this work to previous microwave and infrared data. 相似文献
937.
Polarized memory, i.e., the memory in which switching between ON and OFF states depends on the polarity of bias voltage has been found in point contact diodes on single crystals of CdSe, CdS, CdTe, GaAs and GaP. The detailed features of switching characteristics depend on the choice of metals for the point contact electrode, on the sharpness of the contact and also on the resistance of the current limiter in the circuit. Observation of the transients between ON and OFF has also been performed. 相似文献
938.
Shosuke Yamamura Seiji Kosemura Shigeru Ohba Masatoki Ito Yoshihiko Saito 《Tetrahedron letters》1981,22(52):5315-5318
Two new toxic substances, euphoscopins A and B, have been isolated from the plant L., and their absolute stereostructures also been elucidated on the basis of their spectral data coupled with an X-ray crystallographic analysis of the -bromobenzoate readily obtained on treatment of euphoscopin A with -bromobenzoyl chloride - pyridine. These antitumor substances belong to a group of jatrophone-type diterpenes. 相似文献
939.
940.