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101.
Seiji Yamaguchi Mika Yoshida Izumi Miyajima Toshikatsu Araki Yoshiro Hirai 《Journal of heterocyclic chemistry》1995,32(5):1517-1519
Condensation of salicylonitrile with ethyl α-bromo-α-(o-ethoxycarbonylphenyl)acetate (4) effectively gave 5 (6H)-benzofuro[3,2-c]isoquinolinone (2) , which was converted to some 5-substituted benzofuro-[3,2-c]isoquinoline derivatives 1a-g. 相似文献
102.
Stefan Machill Takahisa Shodai Yoji Sakurai Jun-ichi Yamaki 《Journal of Solid State Electrochemistry》1999,3(2):97-103
Tin-based composite oxide materials have received considerable attention as potential anode materials for rechargeable lithium
batteries. In this contribution we present the results of our investigations of the SnOB2O3P2O5 system. We have investigated its electrochemical properties and especially its cycling performance. A focus of our interest
was to explain the structural changes which occur during lithium cycling and their strong dependence on the preparation method.
A part of the SnO component was converted into a very stable metallic phase. In addition, a decrease was observed in capacity
owing to the formation of isolated and inactive tin grains. We also report on structural changes in the B2O3P2O5 matrix.
Received: 2 October 1997 / Accepted: 3 July 1998 相似文献
103.
V. A. Kul’bachinskii A. Yu. Kaminskii N. Miyajima M. Sasaki H. Negishi M. Inoue H. Kadomatsu 《JETP Letters》1999,70(11):767-771
The quantization of the Hall resistivity ρxy in the form of plateaus in the dependence of ρxy on the magnetic field B is observed in the semiconductors Bi2Te3 and Sb2Te3; the minima of the transverse magnetoresistivity ρxx correspond to the start of the plateaus. The quantization of ρxy is due to the presence of a current-carrier reservoir. An impurity band with a high density of states or a different band
with a much higher current-carrier effective mass serves as the reservoir.
Pis’ma Zh. éksp. Teor. Fiz. 70, No. 11, 754–758 (10 December 1999) 相似文献
104.
105.
The phase transition behaviour of two optically isotropic, thermotropic cubic mesogens 1,2-bis-(4-n-undecyloxy- and 4-n-dodecyloxy-benzoyl)hydrazine, BABH(11) and BABH(12), was investigated under hydrostatic pressures up to 300 MPa using a high pressure differential thermal analyser, a wide angle X-ray diffractometer and a polarizing optical microscope equipped with a high pressure optical cell. It is found that for BABH(11) and BABH(12), a smectic C (SmC) phase is induced between the isotropic liquid (I) and the cubic (Cub) phases by applying pressures above 10-12 and 16-17 MPa, respectively. A sea-island texture consisting of bright sand-like sea regions (SmC phase) and areas of dark islands (Cub phase) appears in the mesophase under pressures up to 140 MPa, while the sand-like texture of the SmC phase is formed predominantly on cooling under pressure. These observations indicate the destabilization of the cubic phase with increasing pressure. The phase transition sequence of BABH(11) and BABH(12), Cr-Cub-I at atmospheric pressure, changes to Cr-Cub-SmC-I under intermediate pressures and would change to Cr-SmC-I under elevated pressure. 相似文献
106.
Kiriyama H Yamakawa K Nagai T Kageyama N Miyajima H Kan H Yoshida H Nakatsuka M 《Optics letters》2003,28(18):1671-1673
We report a high-average-power laser-diode-pumped Nd:YAG master oscillator power amplifier system that has a minimum number of elements in the single multipass zigzag-slab amplifier stage and is used to pump a high-peak-power and high-average-power Ti:sapphire laser system. This phase-conjugated system produces an average power of 362 W at 1 kHz in a 30-ns pulse with an optical-to-optical conversion efficiency of 14%. With an external KTP doubler this system generates 132 W of green average output power at 1 kHz with a conversion efficiency of 60% when pumped at a power level of 222 W. To the best of our knowledge these results represent the highest average output power at both infrared and green wavelengths achieved in a single amplifier stage. 相似文献
107.
Goh Miyajima Hiromichi Akiyama Kichisuke Nishimoto 《Magnetic resonance in chemistry : MRC》1972,4(6):811-823
C-13 and F-19 NMR spectra of seventeen para-substituted fluorobenzenes were measured and the chemical shifts as well as coupling constants with respect to substituents were analysed. The chemical shifts of the fluorine, the C1 and the C2 atoms were found to depend on the total electron densities. In the case of the C3 atom, the chemical shifts seem to depend on π-electron densities rather than the total electron densities. The present calculations also indicate that the chemical shift of the C4 atom depends mainly on σ-electron densities due to the inductive effects of substituents. The strongest factor influencing the coupling constant, nJ(C? F), is also considered to be the π-electron densities on the carbon atoms. In the case of the direct couplings, 1J(C? F), the π-bond orders are important. 相似文献
108.
The penalty function formulation of the finite element method is described for the analysis of transient incompressible creeping flows. Marker particles are utilized to represent moving free surfaces and to visualize the flow patterns. For determining the movement of markers from element to element, the area coordinate system of the linear triangular element is introduced. With the method presented, a punch indentation problem and an injection problem for an L-shaped cavity are solved for Newtonian and power-law fluids. 相似文献
109.
Goh Miyajima Kensuke Takahashi Kichisuke Nishimoto 《Magnetic resonance in chemistry : MRC》1974,6(8):413-418
Carbon-13 chemical shifts of sixteen monosubstituted ethylenes were obtained. In order to explain the chemical shifts, σ and π electron densities of these compounds are calculated by the σ-included ω-HMO method. 1 See Ref. 8. A linear relationship exists between carbon-13 chemical shifts and the calculated electron densities, and also between substituent constants and electron densities. A slope of unity is obtained between the chemical shifts of α carbons of monosubstituted ethylenes and those of carbons adjacent to the substituents in monosubstituted benzenes. On the other hand, a plot of chemical shifts of Cortho of benzene derivatives against that of the β carbon in ethylene derivatives gives a slope of 3. These slopes can be explained by the calculated electron densities. A slope of 4/3 is obtained between the direct coupling constant 1J(C? H) of the α carbon in monosubstituted ethylenes and that in the corresponding substituted methanes. 相似文献
110.