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971.
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974.
Ito M Hori J Kurisaki H Okada H Perez Kuroki AJ Ogita N Udagawa M Fujii H Nakamura F Fujita T Suzuki T 《Physical review letters》2003,91(7):077001
We performed resistivity measurements in CuRh2S4 under quasihydrostatic pressure of up to 8.0 GPa, and found a pressure-induced superconductor-insulator transition. Initially, with increasing pressure, the superconducting transition temperature T(c) increases from 4.7 K at ambient pressure to 6.4 K at 4.0 GPa, but decreases at higher pressures. With further compression, superconductivity in CuRh2S4 disappears abruptly at a critical pressure P(SI) between 5.0 and 5.6 GPa, when it becomes an insulator. 相似文献
975.
Takeshi Tsuchida Akihiro Sakata Ryusaburo Furuichi Tadao Ishii 《Thermochimica Acta》1981,43(1):91-102
The physicochemical properties and reactivity of amorphous aluminas, Al2O3(C1) and Al2O3(N), which were prepared by the thermal decomposition of AlCl3 · 6 H2O and Al(NO3)3 · 9 H2O at 600°C for 2–300 h, were investigated by means of TG, DTA, X-ray diffraction, SEM and IR. The reactivity of Al2O3(Cl) for ZnAl2O4 formation was, in general, higher than that of Al2O3(N) and was influenced by the content of residual chlorine in Al2O3(Cl). The rate of ZnAl2O4 formation followed the Avrami—Erofeev equation in the ZnOAl2O3(Cl) system and the Jander equation ZnOAl2O3(N) system, respectively. 相似文献
976.
977.
We review various methods used to study the dispersion managed soliton for nonlinear return-to-zero pulse propagation in optical fibers. A numerical averaging method, the guiding center soliton, the variational method both with a simple and with an extended ansatz, as well as the multiscale theory are discussed and numerically compared, allowing us to show their domains of applicability. Their relative merits and demerits are then exposed. (c) 2000 American Institute of Physics. 相似文献
978.
Melt rheology of long-chain-branched polypropylenes 总被引:2,自引:0,他引:2
Masataka Sugimoto Yasuhiro Suzuki Kyu Hyun Kyung Hyun Ahn Tsutomu Ushioda Akihiro Nishioka Takashi Taniguchi Kiyohito Koyama 《Rheologica Acta》2006,46(1):33-44
Rheological properties of long-chain-branched isotactic polypropylene (PP) via copolymerization with a very small amount of
nonconjugated α,ω-diene monomer using metallocene catalyst system in both linear and nonlinear regions were investigated,
comparing with conventional linear and long-chain-branched PP modified at postreactor. Although comonomer incorporation was
equal to 0.05 mol% or less, it caused high molecular weight, broad molecular weight distribution, and long-chain branching.
A detailed study on the effect of diene incorporation on the polymer properties was conducted, comparing with modified PP
in postreactor. Polymer chain microstructures were characterized by gel permeation chromatography with multiangle laser light
scattering (MALLS), differential scanning calorimetry, and rheological means: dynamic viscoelasticity, step-strain, uniaxial
elongational flow measurements, and large amplitude oscillatory shear. The PP, which incorporated a small amount of diene
monomer, showed significantly improved viscoelastic behaviors. The diene-propylene copolymer containing long-chain branches
showed extremely long relaxation mode under shear and outstanding viscosity increase under elongational flow, so-called strain
hardening. The difference in microstructure of diene-propylene copolymer with modified PP with long-chain branches is investigated
by MALLS and rheological characterizations. 相似文献
979.
Approximate vibration analysis of laminated curved panel using higher-order shear deformation theory
An approximate analysis for free vibration of a laminated curved panel (shell) with four edges simply supported (SS2), is
presented in this paper. The transverse shear deformation is considered by using a higher-order shear deformation theory.
For solving the highly coupled partial differential governing equations and associated boundary conditions, a set of solution
functions in the form of double trigonometric Fourier series, which are required to satisfy the geometry part of the considered
boundary conditions, is assumed in advance. By applying the Galerkin procedure both to the governing equations and to the
natural boundary conditions not satisfied by the assumed solution functions, an approximate solution, capable of providing
a reliable prediction for the global response of the panel, is obtained. Numerical results of antisymmetric angle-ply as well
as symmetric cross-ply and angle-ply laminated curved panels are presented and discussed. 相似文献
980.
The advantages of using a four-track steering (4TS) vehicle are less slippage and sinkage of the tracks in turning, compared with conventional skid-steering tracked vehicles. This paper describes the steerability and the mobility of the 4TS vehicle for on- and off-road conditions. Mathematical models have also been developed to predict the effects of various types of differential torque transfer on the handling behavior of a vehicle. A turning vehicle motion was simulated and compared with the experimental data. The results demonstrate that the proposed mathematical model could accurately assess the steering performance of a 4TS vehicle. 相似文献