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31.
Masamura Shinnosuke Iwamoto Tetsu Sugitani Yoshiki Konishi Keiji Hara Naoyuki 《Nonlinear dynamics》2020,99(4):3155-3168
Nonlinear Dynamics - The present study experimentally investigates amplitude death in delay-coupled double-scroll circuits with a time-varying network topology that randomly changes at a regular... 相似文献
32.
Tsuda O Ishihara M Koga Y Fujiwara S Setsuhara Y Sato N 《The journal of physical chemistry. B》2005,109(11):4917-4922
Three-dimensional plasma enhanced chemical vapor deposition (CVD) of hydrogenated amorphous carbon (a-C:H) has been demonstrated using a new type high-density volumetric plasma source with multiple low-inductance antenna system. The plasma density in the volume of phi 200 mm x 100 mm is 5.1 x 10(10) cm(-3) within +/-5% in the lateral directions and 5.2 x 10(10)cm(-3) within +/-10% in the axial direction for argon plasma under the pressure of 0.1 Pa and the total power as low as 400 W. The uniformity of the thickness and refractive index is within +/-3.5% and +/-1%, respectively, for the a-C:H films deposited on the substrates placed on the six side walls, the top of the phi 60 mm x 80 mm hexagonal substrate holder in the pure toluene plasma under the pressure is as low as 0.04 Pa, and the total power is as low as 300 W. It is also found that precisely controlled ion bombardment by pulse biasing led to the explicit observation in Raman and IR spectra of the transition from polymer-like structure to diamond-like structure accompanied by dehydrogenation due to ion bombardment. Moreover, it is also concluded that the pulse biasing technique is effective for stress reduction without a significant degradation of hardness. The stress of 0.6 GPa and the hardness of 15 GPa have been obtained for 2.0 microm thick films deposited with the optimized deposition conditions. The films are durable for the tribology test with a high load of 20 N up to more than 20,000 cycles, showing the specific wear rate and the friction coefficient were 1.2 x 10(-7) mm3/Nm and 0.04, respectively. 相似文献
33.
Yoshitomo Ono Naoyuki Kawashima Hiroto Kudo Tadatomi Nishikubo Takabumi Nagai 《Journal of polymer science. Part A, Polymer chemistry》2005,43(19):4412-4421
The ring‐opening copolymerization of donor–acceptor norbornadiene (D–A NBD) dicarboxylic acid monoglycidyl ester derivatives with D–A NBD dicarboxylic acid anhydride was performed with tetraphenylphosphonium bromide as a catalyst in toluene to produce new norbornadiene (NBD) polyesters containing D–A NBD moieties in the main chain and in the side chain in one step in good yields. The photoisomerization of the D–A NBD moieties in these polyesters proceeded very smoothly to give the corresponding quadricyclane groups. Because these NBD polyesters contained many NBD moieties in the polymer chain, they had the highest capacity for heat storage in the D–A NBD polymers reported so far. The stored thermal energy of the irradiated polyesters was evaluated by differential scanning calorimetry analysis to be approximately 150–190 J/g. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4412–4421, 2005 相似文献
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Properties of the levels in 112In have been studied with the reaction 112Cd(p, nγ)112In. The level scheme of 112In below 1300 keV was constructed from the γ-ray excitation functions and γγ coincidences. In 112In, 22 excited states were observed and spins and parities of 8 excited states were newly assigned or restricted by comparing the measured angular distributions and linear polarizations of the deexciting γ-rays as well as the excitation functions of the residual levels with the predictions of the statistical compound nucleus model. Possible configurations of the low-lying levels are discussed in terms of their decay properties and the systematics of the excited states in the neighbouring doubly odd In isotopes. 相似文献
37.
The bioultrasonic spectroscopy system was employed for measurements of velocity and attenuation coefficient of glucose solutions in the VHF/UHF range. The relation between the slope of the square of velocity and the relaxation parameters, and the relation between the frequency exponent on attenuation coefficient and the relaxation parameters are investigated. In order to carry out numerical calculations, a model for a single relaxation process is employed, wherein the attenuation coefficient is expressed as (A/( 1 + (f/falpha)2) + B)f2 where falpha is the attenuation relaxation frequency, and A and B are constants. The numerical calculations show that the slope of the square of the velocity is determined uniquely by the velocity relaxation frequency fv and v(infinity)2 - v(0)2 where v0 is the zero-frequency velocity and v(infinity) is the infinite-frequency velocity, and that the frequency exponent on the attenuation coefficient is determined uniquely by falpha and A/B. For experimental considerations, the velocities and the attenuation coefficients of 5, 15, and 25% concentration aqueous solutions of glucose were measured in the frequency range 20 to 700 MHz. The data for the 5 and 15% aqueous solutions can be explained using the single relaxation model. However, the data for the 25% aqueous solution suggest the existence of multirelaxation processes. 相似文献
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39.
Ignition enhancement by addition of NO and NO2 from a N2/O2 plasma torch in a supersonic flow 总被引:1,自引:0,他引:1
Kenichi Takita Naoyuki Abe Goro Masuya Yiguang Ju 《Proceedings of the Combustion Institute》2007,31(2):2489-2496
The effects of NO and NO2 produced by using a plasma jet (PJ) of a N2/O2 mixture on ignition of hydrogen, methane, and ethylene in a supersonic airflow were experimentally and numerically investigated. Numerical analysis of ignition delay time showed that the addition of a small amount of NO or NO2 drastically reduced ignition delay times of hydrogen and hydrocarbon fuels at a relatively low initial temperature. In particular, NO and NO2 were more effective than O radicals for ignition of a CH4/air mixture at 1200 K or lower. These ignition enhancement effects were examined by including the low temperature chemistry. Ignition tests by a N2/O2 PJ in a supersonic flow (M = 1.7) for using hydrogen, methane, and ethylene injected downstream of the PJ were conducted. The results showed that the ignitability of the N2/O2 PJ is affected by the composition of the feedstock and that pure O2 is not the optimum condition for downstream fuel injection. This result of ignition tests with downstream fuel injection demonstrated a significant difference in ignition characteristics of the PJ from the ignition tests with upstream fuel injection. 相似文献
40.
Yoko Hirohara Yoshitaka OKawa Toshifumi Mihashi Tatsuo Yamaguchi Naoki Nakazawa Yasuko Tsuruga Hiroyuki Aoki Naoyuki Maeda Ichiro Uchida Takashi Fujikado 《Optical Review》2007,14(3):151-158
The purpose of this paper was to investigate the feasibility of a newly developed hyperspectral fundus imaging camera with
a liquid crystal tunable filter. The intensities of different wavelengths of light transmitted through an artery, vein, and
the area surrounding these vessels and reflected out were measured, and the differential spectral absorptions were analyzed.
Measurements were made from 16 normal eyes and from two artificial capillaries. The ratios of absorption (ROA) of arteries
to veins from 500 to 580 nm (range 1) and from 600 to 720 nm (range 2) were calculated. For all eyes, the ROArange1 was larger than ROArange2. The ROA obtained from the artificial capillary filled with blood saturated with oxygen or nitrogen was similar to that of
simulated data of oxy- and deoxyhemoglobin extinction rate. Most ROAs of human eyes were lower than those of the simulated
data and the artificial capillaries. Oxygen saturation analysis by hyperspectral fundus imaging of retinal vessels were qualitatively
in agreement with thein vitro analysis or simulated values. However, further improvements are necessary to evaluate the oxygen saturation quantitatively
in the retinal blood vessels. 相似文献