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61.
Kato N Sakayanagi M Nakayama T Nishimura H Ogamo A 《Journal of chromatography. A》2002,973(1-2):159-166
A novel detection method for 21 different anions by thin-layer chromatography is presented. Anions on the target plate form salts with amine in a developing solvent and are visualized after staining with citric acid-acetic anhydride reagent as white spots contrasting against a pale red-pink background. This method has particularly high sensitivity for anions of chlorate, sulfate, phosphate, chromate and dichromate (0.02-0.05 microg). The method is demonstrated to efficiently detect toxic arsenite in curry sauce as an example application. The proposed method offers highly efficient indirect detection for a wide range of anions, and serves as a purification procedure for the preparation of anionic sample solutions for other analytical methods. 相似文献
62.
We demonstrate chlorine-induced modification of Si(100)-(2 x 1) under conditions where Cl is recycled rather than desorbed as SiCl2. A dimer with 2 Cl atoms, 2SiCl, converts to SiCl2+Si, allowing the bare Si atom to escape onto the terrace. At temperatures below the desorption threshold, the SiCl2 unit decays through Cl diffusion, allowing the second Si atom to escape. The result is a dimer vacancy, terrace regrowth structures, and Cl that is able to participate in another pitting event. Access to this unexpected roughening pathway is controlled by the Cl concentration and temperature. This previously overlooked process represents an important component of Si(100) surface processing. 相似文献
63.
The design secret of Kyokusui-no-En’s meandering channel 总被引:1,自引:0,他引:1
The purpose of this study is to investigate the characteristics of the flow through the Jonangu channel which is used for
ceremonial game called as ‘Kyokusui-no-En’ in Japanese. The geometry of the channel is measured, a visualization technique
is used to measure the actual flow characteristics, and then a numerical flow model is used to represent the flow including
unsteady flow characteristics. Numerical model of drifting cup is introduced to investigate an interaction between flow and
motion of the cup. Finally, the intention of the channel design is interpreted from the viewpoint of fluid mechanics using
observed and calculated results. 相似文献
64.
65.
Wavelength dependence of the photocurrent in irradiated naphthalene single crystal was measured and a broad band peaked at 1.8 eV was found. This band was ascribed to the transition of a charge carrier trapped by the radical into a continuum. The width of the continuum was determined as 0.63+0.2-0.05 eV. 相似文献
66.
The surface-induced valley-splitting theory by Sham and Nakayama is shown in the special case of a two-band model for the silicon band structure to be closely related to the electric break-through effect of Ohkawa and Uemura. Recent criticisms of our theory by Ohkawa are shown to be erroneous. 相似文献
67.
68.
Yasuto Uchio Junzo Toyota Hiroshi Nozaki Mitsuru Nakayama Yoshifumi Nishizono Tsunao Hase 《Tetrahedron letters》1981,22(41):4089-4092
The structures of lobohedleolide (1) and (7Z)-lobohedleolide (2), two new cembranolides containing the α,β-unsaturated carboxylic acid system isolated from the Japanese soft coral Lobophytum hedleyi Whitelegge, were elucidated from spectral and chemical evidence, and the absolute configuration of (1) was determined by X-ray analysis of its p-bromophenacyl ester (9). Lobohedleolide (1) showed growth inhibition of the in vitro Hella cells. 相似文献
69.
70.
Sodium vapour in a sealed cell is irradiated by two counter-propagating but laterally displaced beams from the same laser, tuned to one of the hf components of the D1 line. Atoms pumped by the stronger beam, circularly polarized, precess in a transverse magnetic field, < 300 mG, during their passage to the weaker beam where their orientation is monitored. The observed signals are interpreted quantitatively. 相似文献