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841.
Application of Rainbow Schlieren Deflectometry for Axisymmetric Supersonic Jets (Comparison of Experiments with Numerical Analysis) 总被引:1,自引:1,他引:0
This paper analyzes the correctly-expanded supersonic jet from a convergent-divergent
axisymmetric nozzle by using numerical simulation of turbulent flow.And the calculated density
distributions in this flow are compared with the present experimental data using rainbow schlieren
deflectometry.The value of the density from the experimental data agrees well with the results
calculated by this simulation.Therefore,the present method of the measurement using rainbow
schlieren deflectometry is useful for the measurement of the density of the correctly-expanded
supersonic jet. 相似文献
axisymmetric nozzle by using numerical simulation of turbulent flow.And the calculated density
distributions in this flow are compared with the present experimental data using rainbow schlieren
deflectometry.The value of the density from the experimental data agrees well with the results
calculated by this simulation.Therefore,the present method of the measurement using rainbow
schlieren deflectometry is useful for the measurement of the density of the correctly-expanded
supersonic jet. 相似文献
842.
Shin-ichi Muramatsu Tsuyoshi Uematsu Hiroyuki Ohtsuka Yoshiaki Yazawa Terunori Warabisako Hiroshi Nagayoshi Kouichi Kamisako 《Solar Energy Materials & Solar Cells》2001,65(1-4)
Remote plasma was used for PE-CVD of SiN films and it was found that hydrogen radical (H* ) annealing of c-Si cells with SiN films improved the efficiency of the cells. Cell efficiency of 21.8% was obtained by applying a SiN/SiO2 double-layer structure on the emitter of a PERL-type solar cell. It was found that the H* annealing has two effects: it reduces surface recombination velocity (SRV); and it degrades bulk-lifetime of p-type c-Si. To apply SiN practically, it is effective to use a rear n-floating or a triode structure. Reducing the exposed area of the p-type substrate by using n-type diffused layer increases the efficiency of solar cells. 相似文献
843.
Yoshiaki Matsukawa Masayuki Watanabe Yasunori Mitani Mohammad Lutfi Othman 《Electrical Engineering in Japan》2019,207(2):20-27
The optimal phasor measurement unit (PMU) placement problem in power systems has been considered and investigated by many researchers for accurate and fast state estimation by PMUs. However, the current channel cost of the PMU affects the total placement cost. This paper proposes a novel formulation in the multi‐objective optimal PMU placement, which minimizes the PMU placement cost with the current channel selection and the state estimation error. The current channel selection is represented as a decision variable in the optimization. For trade‐off objective functions, the Pareto approach by nondominated sorting genetic algorithm II (NSGA‐II) is applied in the optimization. The result of the numerical experiment in this paper demonstrates the advantage of considering the appropriate PMU current channel allocation, compared with the conventional method that ignores it, in the modified IEEE New England 39‐bus test system. As a result, the proposed method obtained a better Pareto solution compared with the conventional one because of the consideration for the current channel selection. An advantage of the proposed PMU placement is that it is able to reduce the total PMU placement cost while maintaining the state estimation accuracy. 相似文献
844.
Yoshiaki Miyazato Yong-Hun Kweon Toshiyuki Aoki Mitsuharu Masuda Kwon-Hee Lee Heuy-Dong Kim Toshiaki Setoguchi Kazuyasu Matsuo 《热科学学报(英文版)》2003,12(3):260-263
The acoustic properties of supersonic jet noise from a convergent-divergent nozzle with a baffle have been studied experimentally over the range of nozzle pressure ratios from 2.0 to 8.0. Acoustic measurements were conducted in a carefully designed anechoic room providing a free-field environment. A new approach for screech noise suppression by a cross-wire is proposed. Schlieren photographs were taken to visualize the shock wave patterns in the supersonic jet with and without the cross-wire. The effects of the baffle and the cross-wire on acoustic properties are discussed. It is shown that the baffle has little effect on the screech frequency for the underexpanded supersonic jet without the cross-wire. Also, the cross-wire introduced in supersonic jets is found to lead to a significant reduction in overall sound pressure level. 相似文献
845.
Inamori K Kyo M Nishiya Y Inoue Y Sonoda T Kinoshita E Koike T Katayama Y 《Analytical chemistry》2005,77(13):3979-3985
We describe herein a detection and quantification system for on-chip phosphorylation of peptides by surface plasmon resonance (SPR) imaging techniques using a newly synthesized phosphate capture molecule (i.e., biotinylated zinc(II) complex). The biotinylated compound is a dinuclear zinc(II) complex that is suitable for accessing phosphate anions as a bridging ligand on the two zinc(II) ions. The compound was exposed on the peptide array and detected with streptavidin (SA) via a biotin-SA interaction by SPR imaging. In the conventional method using antibody, both anti-phosphoserine and anti-phosphotyrosine antibodies were required for phosphoserine and phosphotyrosine detection, respectively. Detection of the phosphate group by the zinc(II) complex, however, was independent of the phosphorylated amino acid residues. The calibration curve for the phosphorylation ratios was established with a calibration chip, on which phosphoserine-containing peptide probes were immobilized. The peptide probes, which were phosphorylated on the surface by protein kinase A, were detected and quantified by SPR imaging using the zinc(II) complex, SA, and anti-SA antibody. The reaction rate and the kinetics of on-chip phosphorylation were also evaluated with the peptide array. The phosphorylation ratio was saturated at approximately 20% in 2 h in this study. 相似文献
846.
Scanning electron microscopic observation of immunohistochemically specified stromal cells following the NaOH maceration method 总被引:2,自引:0,他引:2
The present study introduces a method combining immunohistochemistry and a chemical digestion technique applied to scanning electron microscopy (SEM) observation of chemically characterized stromal cells in the myenteric layer of the monkey small intestine. The whole-mount preparation containing the myenteric layer was treated immunohistochemically using small colloidal gold and silver enhancements for detecting a certain type of stromal cell, followed by an alkali maceration method to remove extracellular matrices covering the immunohistochemically stained cells. This method permitted direct SEM observation of the stained stromal cells. Secondary and backscatter electron images clearly visualized the ultrastructure of the immunohistochemically-stained cells and the spatial distribution of the reaction products, respectively. It is suggested that the present method is useful for demonstrating the three-dimensional organization of the chemically specified stromal cells. 相似文献
847.
A method that uses two quadrant detectors (QDs) for sensing wave-front tilt is described. The detectors are set at the front and back of the focal plane of the focusing optics. When the intensity distribution at the aperture of a telescope is not uniform because of atmospheric turbulence, the wave-front tilt can be measured more accurately with our two-QD method than with a conventional single-focal-plane QD. We proved this method to be effective by using it for fixed-star observation. Application of the method to a ground-to-satellite laser beam pointing system showed that it increases the intensity of the laser beam that is transmitted to a satellite. 相似文献
848.
The matrix eigenvalue problem Hui = λi ui is considered. It is shown that when a new approximate vector v(n+1) to u1 (the eigenvector of the lowest eigenvalue) is computed from the present one v(n) by the relation v(n+1) = (1? αH + βH2) v(n) or v(n+1) = (1? αH + βH2 – γH3) v(n), the convergence rate is at least double that of the gradient method which corresponds to set β = γ = 0. Moreover, by choosing parameters α, β, or γ properly, one can get about three to five times faster convergence rate than that of the latter method, for H having very small γ2–γ1 and very large λN (the largest eigenvalue), further modifications are suggested. The relation with the Richardson method is also discussed. 相似文献
849.
Yoshiyuki Nakazawa Yukiko Kamijo Keiji Fujimoto Haruma Kawaguchi Yoshiaki Yuguchi Hiroshi Urakawa Kanji Kajiwara 《大分子材料与工程》1996,240(1):187-196
Monodisperse hydrogel microspheres were prepared by precipitation polymerization from acrylamide (AAm), methylenebisacrylamide (MBAAm) and methacrylic acid (MAc) in ethanol, and examined their stimuli response by changing pH or temperature. The microsphere was found to contract continuously by heating. The microsphere with a lower-content MBAAm exhibit more pronounced heat-contraction. Also at low pH the microsphere contracted due to the protonation of the carboxyl group in MAc. The internal structure was observed by small angle X-ray scattering (SAXS) and the stimuli-response mechanism was discussed from the view of network chain conformation. 相似文献
850.
Tohru Ohyama Kazuo Jin Yoshinobu Katoh Yoshiaki Chiba Katsuhiro Inoue 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(3):F8
Chemical reactions in foods II 相似文献