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721.
Akio Hiraki Yoshito Fukushima Takashi Sato Hideki Kiyono Hitoshi Terauchi Takeshi Imura 《Journal of Non》1983
When a slight fraction (~ 2 mol %) of N2 is added into H2, sputtering atmosphere for microcrystalline hydrogenated Si films, without changing other fabrication parameters, the amorphous film rather than microcrystalline one forms. The stabilization mechanism of the amorphous film of Si is discussed through TEM and IR observations of this kind of transformation from microcrystal to amorphous state. 相似文献
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723.
Detection of filamentous bulking problems: developing an image analysis system for sludge composition monitoring. 总被引:2,自引:0,他引:2
Rika Jenné Ephraim Noble Banadda Ilse Smets Jeroen Deurinck Jan Van Impe 《Microscopy and microanalysis》2007,13(1):36-41
This article describes a fully automatic image analysis procedure for fast and reliable characterization of the activated sludge composition, that is, the floc and filament features. The algorithms developed for each of the analysis steps, that is, segmentation, object recognition, and characterization, are described in detail. Although the application range of the recognition method is a priori expanded by introducing a number of control parameters, the procedure proves to be intrinsically robust as it produces satisfactory results for a fixed set of parameter values for a wide variety of image types. 相似文献
724.
M Tokunaga T Suzuki N Koga T Fukushima A Horiuchi Y Wakatsuki 《Journal of the American Chemical Society》2001,123(48):11917-11924
The mechanism of the selective conversion of 1-alkynes to aldehydes by hydration was investigated by isolating organic and organometallic byproducts, deuterium-labeling experiments, and DFT calculations. The D-labeled acetylenic hydrogen of 1-alkyne was found exclusively in the formyl group of the resulting aldehydes. After the reaction, the presence of metal-coordinated CO was confirmed. All of the experimental results strongly suggest the involvement of a metal-acyl intermediate with the original acetylenic hydrogen also bound to the metal center as a hydride, with the next step being release of aldehyde by reductive elimination. Theoretical analyses suggest that the first step of the catalytic cycle is not oxidative addition of acetylene C [bond] H or tautomerization of eta(2)-alkyne to a vinylidene complex, but rather protonation of the coordinated 1-alkyne at the substituted carbon to form a metal-vinyl intermediate. This cationic intermediate then isomerizes to Ru(IV)-hydride-vinylidene via alpha-hydride migration of the vinyl group to the metal center, followed by attack of the vinylidene alpha-carbon by OH(-) to give the metal-hydride-acyl intermediate. 相似文献
725.
Koji Hatanaka Ken-ichiro Yomogihata Hiroshi Ono Kei Nagafuchi Hiroshi Fukumura Michiko Fukushima Tomohiro Hashimoto Saulius Juodkazis Hiroaki Misawa 《Journal of Non》2008,354(52-54):5485-5490
We have generated hard X-rays by front- and back-side femtosecond laser irradiation of PbO-rich glass. The actual Pb content of glasses was corroborated by Pb M-line emission intensities with an uncertainty of less than 20%. The elements K and As at concentrations of a few mol% were detected. X-ray generation by back-side irradiation helped to avoid an air breakdown; however, self-focusing and filamentation limited the achievable light intensity and effectiveness of X-ray generation. Characteristics and mechanisms of X-ray generation from the front- and back-side of glasses are discussed. 相似文献
726.
Kazunaka Endo Daisuke Matsumoto Yusuke Takagi Motohiro Mizuno Kazuhiko Fukushima 《Applied Surface Science》2008,255(4):1048-1051
Simulations with a quantum molecular dynamics (QMD) method (MD with MO) were demonstrated on the thermal decomposition of lignin monomer at the ground state including excited and positive charged states. Geometry and energy optimized results of the lignin monomer at the singlet and triplet states in single excitation, and at (+2) positive charged state by semi-empirical AM1 MO calculations were used as the initial MD step of QMD calculations. In the QMD calculations, we controlled the total energy of the system using Nóse-Hoover thermostats in the total energy range of 0.69-0.95 eV, and the sampling position data with a time step of 0.5 fs were carried out up to 5000 steps at 50 different initial conditions. The calculated neutral, positive and negative charged fragment distributions of the monomer model with 0.82 eV energy control were obtained as 90.6, 3.5, and 5.9% to the total fragments, respectively. The ratios seem to correspond well with to the values observed experimentally in SIMS. 相似文献
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728.
729.
To deal with the robust portfolio selection problem where only partial information on the exit time distribution and on the conditional distribution of portfolio return is available, we extend the worst-case VaR approach and formulate the corresponding problems as semi-definite programs. Moreover, we present some numerical results with real market data. 相似文献
730.