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991.
Branching ratio for preionization and predissociation of a superexcited state of a diatomic molecule
Hiroki Nakamura 《Chemical physics letters》1975,33(1):151-155
The branching ratio for preionization and predissociation is studied qualitatively on the basis of a previously proposed simplisitc classical probabilistic model of the superexcited states of molecules. The isotope effect is also discussed. 相似文献
992.
Shigeo Kato Shigeharu Harada Hiroki Nakashima Hiroyasu Nomura 《Journal of colloid and interface science》1992,150(2)
Ultrasonic absorption measurements of aqueous solutions of sodium perfluorooctanoate (SPFO) and of cesium perfluorooctanoate (CsPFO) were carried out in the frequency range 0.2–90 MHz at 25°C. A single ultrasonic relaxation process is observed in all solutions investigated. The observed relaxation process should be ascribed to a “fast” relaxation process due to an exchange of surfactant monomer between micelle and bulk solution. The mean dissociation rate constant and the magnitude of the volume difference due to the exchange process are determined by applying the relations derived by Aniansson and Wall and by Teubner, respectively. The ratio of the aggregation number of the micelle to the mean dissociation rate constant
is reduced to about one-half and the volume difference decreases when the counterion of the perfluorooctanoate changes from Na+ to Cs+. Precise density measurements were also carried out to support information obtained from the ultrasonic relaxation study. Magnitudes of the volume difference estimated from the two independent studies above are in approximate agreement with each other. However, the volume difference determined from the density measurements is slightly larger than that determined by ultrasonic study and almost independent of the species of the counterion. 相似文献
993.
Tetsuya Hasegawa Hiroki Haraguchi 《Spectrochimica Acta Part B: Atomic Spectroscopy》1985,40(8):1067-1084
The collisional-radiative model has been applied to the argon ICP discharge in order to elucidate the excitation mechanism in the plasma. The population density distributions of 25 argon energy levels were calculated under a steady-state approximation by using the literature values of electron number density, 5 × 10 14cm?3 and electron temperature, 9000 K. In the case of an optically thin plasma, in which the induced absorption can be neglected, the calculated population densities showed an overpopulation for low lying states, and were very close to LTE values for the upper levels. These results suggest the following excitation mechanisms in the argon ICP; corona model for lower levels and ladder-like excitation and ionization by electron impact for upper levels. According to the present calculation, the non-overpopulation of argon metastable can be interpreted by the interconversion between metastable and radiative states. It has been found that the induced absorption of resonance lines in an optically thick plasma and the motion of species in an inhomogeneous plasma have significant effects on the population densities. The non-linear processes by collision between heavy particles were not predominant compared to electron impact processes. 相似文献
994.
Hisanori Yamane Hiroki Takahashi Takashi Kajiwara Masahiko Shimada 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1177-1178
The title quaternary oxide, trisodium dicalcium tantalum hexaoxide, is isostructural with Li3Ni2TaO6, a partially ordered rock‐salt phase. The Na, Ca and Ta atoms occupy octahedral sites in an orderly manner and form a cation‐ordered superstructure. 相似文献
995.
Hiroki Takamura 《Mathematical Logic Quarterly》2011,57(5):481-484
In this paper, we show that Ogasawa’s theorem has a proof in Bishop style constructive mathematics (BISH). In 25 , we introduced the elementary constructive theory of C*‐algebras in BISH, but we did not discuss the powers of positive elements there. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
996.
Motohiro Aiba Takahiro Tokuyama Hidetoshi Matsumoto Hiroki Tomioka Tomoya Higashihara Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2014,52(24):3453-3462
The synthesis, conformational preferences, hydrogen bonding behaviors, and membrane properties of new partially N‐methylated random aromatic copolyamides were reported. These copolyamides were prepared by the low temperature polycondensations of isophthaloyl chloride with 3,5‐diaminobenzoic acid, N,N'‐dimethyl‐4,4'‐diaminodiphenyl ether (MDAE), and 4,4'‐diaminodiphenyl ether. The incorporation of the N‐methyl amide linkages into the polymer backbone decreased the contents of the cis conformation in the N‐methyl amide linkages and suppressed the hydrogen bondings among the amide linkages. Furthermore, the surface hydrophilicity of the copolyamides evaluated by water contact angle measurements decreased with increasing the MDAE unit in the polymer backbone. These experimental results indicated that the suppression of the hydrogen bonding and the existence of the tertiary amide linkage in the cis conformation induced the loose packing of the polymer chains. As a result, the incorporation of the N‐methyl amide linkage increased water flux and decreased salt rejection. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3453–3462 相似文献
997.
Hiroki Tanaka Masahiko Takino Yoshiko Sugita‐Konishi Toshitsugu Tanaka David Leeman Akira Toriba Kazuichi Hayakawa 《Rapid communications in mass spectrometry : RCM》2010,24(16):2445-2452
A method for the simultaneous quantitative determination of deoxynivalenol (DON), T‐2 toxin (T‐2), HT‐2 toxin (HT‐2) and zearalenone (ZEN) in wheat and biscuit by liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) coupled with immunoaffinity extraction is described. A clean‐up was carried out using a DZT MS‐PREP® immunoaffinity column (IAC), and the effect of the sample dilution rate and sample loading was investigated. Furthermore, the effects of ion suppression of a multifunctional column (MFC) and the IAC in the clean‐up were compared. The results with the DZT MS‐PREP® IAC showed that it is possible to make the sample dilution rate low, and indicated a higher solvent‐tolerance than usual with an IAC. Sample loading was optimized at 0.25 g. Ion suppression was lowered by purification of the toxins using the DZT MS‐PREP® IAC. Recoveries of each mycotoxin from wheat and biscuit samples spiked at two levels ranged from 78 to 109%. The limits of detection in wheat and biscuit was in the range of 0.03–0.33 ng·g?1. From these studies, it is suggested that use of an IAC is effective in the clean‐up of each mycotoxin, and, when combined with LC/ESI‐MS/MS, it is good for the determination of mycotoxins in foodstuffs due to its rapidity and high sensitivity. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
998.
999.
Hiroki Matsui 《Algebras and Representation Theory》2018,21(3):551-563
Classification problems of subcategories have been deeply considered so far. In this paper, we discuss classifying dense resolving and dense coresolving subcategories of exact categories via their Grothendieck groups. This study is motivated by the classification of dense triangulated subcategories of triangulated categories due to Thomason. 相似文献
1000.