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81.
Kanichi Kamiya Tokiti Noda Michio Inagaki Hajime Saito 《Journal of Materials Science》1972,7(11):1244-1248
A soft carbon and a hard carbon which were prepared from Polyvinylchloride and phenolformaldehyde resin, respectively, both by carbonizing to about 700°C, were obtained as sintered cakes by heat-treatment up to about 1800°C under the quasihydrostatic pressure of 5 kbar. Preferred orientation of crystallites relative to the compressing direction in these cakes was determined by X-ray difraction technique by using the (004) or (002) diffraction line. The soft carbon showed remarkable preferred orientation of crystallites, but the degree of orientation was dependent only a little on heat-treatment temperature (HTT). At 1200°C under 5 kbar, the hard carbon gave a sintered cake which had no appreciably preferred orientation. The degree of preferred orientation of crystallites in the cake of the hard carbon greatly increased with the increase in HTT. The difference in the dependence of preferred orientation of crystallites in the soft and hard carbons on HTT was interpreted by referring to the texture of the original carbons. 相似文献
82.
Mau Hsiung Chen Bernd Crasemann Keh-Ning Huang Michio Aoyagi Hans Mark 《Atomic Data and Nuclear Data Tables》1977,19(2):97-151
Relativistic relaxed-orbital calculations of L-shell Coster-Kronig transition energies have been performed ab initio for all possible transitions in atoms with atomic numbers 11 ≤ Z ≤ 103. Hartree-Fock-Slater wavefunctions served as zeroth-order eigenfunctions to compute the expectation of the total Hamiltonian. A first-order approximation to the local approximation was thus included. Quantum-electrodynamic corrections were made. Each transition energy was computed as the difference between results of separate self-consistent-field calculations for the initial, singly ionized state and the final two-hole state. The following quantities are listed: total transition energy, “electric” (Dirac-Hartree-Fock-Slater) contribution, magnetic and retardation contributions, and contributions due to vacuum polarization and self energy. 相似文献
83.
Keiichi Ikegami Shin-Ichi Kuroda Mitsuyoshi Saito Kazuhiro Saito Michio Sugi Takayoshi Nakamura Mutsuyoshi Matsumoto Yasujiro Kawabata 《Thin solid films》1988,160(1-2):139-143
An electron spin resonance (ESR) investigation is performed on Langmuir-Blodgett films consisting of a surface-active 1:2 complex of N-docosylpyridinium and tetracyanoquinodimethane (TCNQ), whose temperature-dependent spin susceptibility has been so far found to be consistent with the random-exchange Heisenberg antiferromagnetic chain (REHAC) model of Soos and Bondeson. An out-of-plane anisotropy in the ESR spectra shows that the long axes of TCNQ molecules are preferentially oriented along the plane normal to the sample, where the negligible in- plane anisotropy indicates the random distribution of the short and the pπ orbital axes in the film plane. A heat treatment applied to the samples results in an increase in the concentration of disorder, showing the possibility of controlling it in the present REHAC system. 相似文献
84.
BACKGROUND: Oral clonidine may influence plasma glucose and lipid homeostasis by modulating endocrinologic responses to surgical stress. The effect of oral clonidine premedication on plasma glucose and lipid homeostasis associated with exogenous glucose infusion were investigated in children undergoing minor surgery. METHODS: Otherwise healthy children (n, 120; aged 3-13 yr) were assigned randomly to six groups according to the glucose concentration of the intravenous solution (0%, 2%, or 5%, at a rate of 6 ml kg(-1) x h(-1)) and the preoperative medications (4 microg/kg clonidine or placebo given 100 min before anesthesia) they were to receive. The plasma concentrations of glucose, nonesterified fatty acid, ketone bodies, epinephrine, norepinephrine, and cortisol were determined. RESULTS: Infusion of 5% glucose caused hyperglycemia (mean glucose concentration >200 mg/dl) in six children receiving placebo and two receiving clonidine. Although the mean plasma glucose concentration increased in three placebo groups, it was unchanged and the plasma concentrations of total ketone bodies and nonesterified fatty acid were increased in children receiving clonidine and glucose-free solution. The plasma epinephrine, norepinephrine, and cortisol levels in children receiving placebo increased in response to surgery. Clonidine attenuated the increase in catecholamines and cortisol. CONCLUSIONS: Oral clonidine premedication attenuated the hyperglycemic response, probably by inhibiting the surgical stress-induced release of catecholamines and cortisol. Infusion of 2% of glucose maintained plasma glucose concentrations within physiologic ranges in children receiving clonidine. 相似文献
85.
The intrinsic response time of InP/InGaAs APD has been reported. The multiplication factor dependent frequency responses were measured up to multiplication factor of 24. The results show the gain bandwidth of InP/InGaAs APDs is 10 GHz, and the intrinsic response time to be 16 ps. 相似文献
86.
Ermittlung der Zusammensetzungen der Vanadinoxide im Gleichgewicht mit Eisen-Vanadin-Legierungen bei 1600 °C und Gehalten bis zu 5% V durch Mikrosonden- und Röntgenbeugungsuntersuchungen nach Abschrecken der Proben mit einem Stahlstab. Angaben zum Zusammenhang zwischen Vanadin- und Sauerstoffaktivität der Schmelzen und zur Sauerstoffsättigung der flüssigen Eisen-Vanadin-Legierungen. Überprüfung der im Schrifttum angegebenen Aktivitätskoeffizienten von Vanadin in Eisenschmelzen. 相似文献
87.
A new type of ship's autopilot system is designed by a statistical approach. A ship's motion at sea is described by a multi-variable autoregressive model using minimum AIC (Akaike's Information Criterion) procedure. Through the fitted model, the ship's behavior is analyzed and an optimal control law for a ship under a newly introduced criterion function is derived. The feasibility of our control system is checked by both digital and hybrid simulations. The results of the simulation show that with our controller the yaw motion is depressed through smoother and less rudder motion than that of the conventional autopilot systems and the ill effect of rolling is avoided. It is expected that the controller has another merit: it is quite robust for possible changes of external environments. Finally, a successful result of an actual sea test is briefly discussed. Thus, the possibility of realizing an entirely new autopilot system by a stochastic model is demonstrated. 相似文献
88.
The dynamic moduli, E′ and E″, and tan δ for PET–CR, PET–EPDM, and PET–UR composites with unidirectional short fibers were studied as a function of temperature by using a Rheovibron. The temperature dependence of tan δ showed three peaks for PET–elastomer composites. The peaks at the low temperature corresponded to the main dispersion of the respective matrixes and the peak at about 140°C to the α-dispersion of PET fiber. A small and broad peak observed at a temperature between 60 and 120°C may be caused by the relaxation of the interface region between fibers and matrix. The longitudinal storage modulus for the composite E was given by the parallel model as \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm E'}_\parallel = V_f \cdot E'_f + V_m \cdot E'_m $\end{document}, where E and E are the storage moduli for fiber and matrix and Vf and Vm are the volume fraction of fiber and matrix, respectively. In the transverse direction of fibers, the composite modulus E was expressed by the logarithmic law of mixing as follows: \documentclass{article}\pagestyle{empty}\begin{document}$ \log E'_ \bot = V_f \cdot \log E'_f + V_m \cdot \log E'_m $\end{document}. The peak values of tan δ from the main dispersion of the respective matrixes were given by the equation, (tan δ⊥max)c/(tan δmax)m 1 ? β · Vf, where (tan δ⊥max)c and (tan δmax)m are the maximum values of the loss tangent for the composite and matrix, respectively, and β is coefficient depending on matrix's type. The β value of PET–CR composite is the largest one among those of the composites. 相似文献
89.
Mutsuyoshi Matsumoto Takayoshi Nakamura Eiichiro Manda Yasujiro Kawabata
Keiichi Ikegami
Shin-Ichi Kuroda Michio SugiGunzi Saito
《Thin solid films》1988,160(1-2):61-66Highly conducting Langmuir-Blodgett (LB) films of the tetramethyltetrathia-fulvalene- alkyltetracyanoquinodimethane (TMTTF-Cn TCNQ, where Cn represents CnH2n+1) system are reported. The electron affinities of the acceptors CnTCNQ (n=14, 18 or 22) in solution are almost the same and lie between those of TCNQ and dimethylTCNQ. These TCNQ derivatives form solid charge transfer complexes with TMTTF. The limiting areas of the complexes, normalized to the number of TCNQ derivatives at the air-water interface, are almost the same irrespective of the donor-to-acceptor ratio and of the length of the alkyl chain, indicating that the areas are governed by the TCNQ moiety. The monolayers of TMTTF-Cn TCNQ (n=14 or 18) are transferred onto solid substrates as LB films. Polarized UV-visible absorption spectra indicate that the long axis of TCNQ is parallel to the film surface. These LB films exhibit lateral conductivities as high as 0.4 S cm-1 and 0.1 S cm-1 when n=14 and n=18 respectively. 相似文献
90.
Mau Hsiung Chen Bernd Crasemann Michio Aoyagi Keh-Ning Huang Hans Mark 《Atomic Data and Nuclear Data Tables》1981,26(6):561-574
Theoretical 1s, 2s, , and energy levels in neutral atoms with 70 ≤ Z ≤ 106 are listed. The computations are relativistic and include complete relaxation. The electric energies are based on Dirac-Hartree-Slater wave functions; a first-order correction to the local approximation is made. The Breit-interaction energy and vacuum-polarization energy are listed separately, and a self-energy correction is included. These calculations differ from earlier work by the authors in that a more accurate, frequency-dependent expression for the Breit energy is employed, a Fermi (rather than uniform) distribution of the nuclear charge is assumed, and a screened self-energy correction is applied to the 1s, 2s, , and levels. Comparison of results with 1967 experimental values adopted by Bearden and new work of Borchert shows better agreement than is provided by earlier calculations with frequency-independent Breit interaction and a uniform nuclear charge distribution. 相似文献