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71.
Li Shu-Min Miao Yan-Gang Zhou Zi-Fang Chen Ji Liu Yao-Yang 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,39(1):29-34
The first Born approximation is used to study the laser-assisted electron capture by a fast proton from a hydrogen atom. The laser modification on differential cross section peaks sharply in the forward direction. With the impact energy increasing, the change in integral cross section becomes notable. The more intense the laser, the greater the cross section is; the lower the frequency, the greater the cross section. 相似文献
72.
Jiří Mach 《Monatshefte für Chemie / Chemical Monthly》1968,99(3):1003-1008
Zusammenfassung Die Dissoziation von Ce2
Suc
3·3 H2O** in Perchlorsäure-Lösungen wurde verfolgt und die Dissoziationskonstanten der Succinationen: (CeSuc)+ und (CeSuc
2)– unter Benützung einer Löslichkeitsmethode in 1m-NH4ClO4-Lösung bei 25°C bestimmt. Die Löslichkeitsprodukte von Ce2
Suc
3: [Ce3+]2[Suc
2–]3, [CeSuc
+]2[Suc
2–], [CeSuc
+][CeSuc
2
–] wurden bestimmt.
18. Mitt.:R. Pastorek, Lanthantartrate im neutralen und alkal. Bereich. Mh. Chem.99, 676 (1968). 相似文献
The dissociation of Ce2 Suc 3·3H2O in perchloric acid solutions was investigated. The dissociation constants of the succinate ions (CeSuc)+ and (CeSuc 2)– were determined inM-NH4ClO4 at 25° using a solubility method and the solubility products of Ce2 Suc 3, i. e. [Ce3+]2[Suc 2–]3, [CeSuc +]2[Suc 2–], [CeSuc +][CeSuc 2 –] measured.
18. Mitt.:R. Pastorek, Lanthantartrate im neutralen und alkal. Bereich. Mh. Chem.99, 676 (1968). 相似文献
73.
74.
Ke Jian Liu Jin Jie Jiang Li Li Ji Xianglin Shi Harold M. Swartz 《Research on Chemical Intermediates》1996,22(5):499-509
Application of the spin trapping technique in intact animals requires an understanding of the stability and distribution of the spin traps and their spin adducts in vivo. We studied the stability of DMPO in vivo in mice using HPLC and the stability of spin adducts of DMPO by EPR in plasma, whole blood, peritoneal fluid, and homogenized heart tissue of the rat. At 15 minutes after intraperitoneal injection DMPO had similar concentrations in the liver, heart, and blood of the mice and 40% remained in the organs 2 hours after the injection. In contrast, the spin adduct DMPO-OH was short lived, with a half-life of 3.0 minutes in plasma, and was not detectable 1 minute after formation in whole blood and homogenized heart tissue. The carbon centered spin adduct DMPO-CH(OH)CH3 was more stable, having half-lives of 16, 11, 3.6, and 0.79 minutes in plasma, peritoneal fluid, whole blood, and homogenized heart tissue, respectively. The spin adduct DMPO-SO3 was sufficiently stable for the adduct to be observed directly from living mice. 相似文献
75.
Compasses are called rusty, if one can draw only the unit circle with them. We prove that from two points A and B, with only rusty compasses, one can draw the points of k-section of AB, and all the vertices of a regular n-gon which has a side AB, where k is any integer greater than 1, and n=3, 4, 5, 6, 8, 12, 17, 257, ..., etc. Generally, let A be (0, 0) and let B be (, 0), then one can draw all the points (x, y) where x and y are any elements in some regular 2
m
-extension of the rational field, for m=1, 2, 3, ... 相似文献
76.
Jiří Hošek 《Czechoslovak Journal of Physics》1991,41(11):1037-1041
We demonstrate within the Ginzburg-Landau model of a confining medium that the surface energy associated with the interface between the normal and the confining phases can be negative, and briefly discuss some consequences of this fact.Dedicated to the memory of M. Gmitro.This work was done at the Niels Bohr Institute Copenhagen, and put into its final form at the Institute of Theoretical Physics, of University of Regensburg. I thank both institutes for their generous hospitality and Professors Poul Olesen and Wolfram Weise for discussions. 相似文献
77.
78.
79.
Jiři Votinský Jaroslava Kalousová Ludvík Beneš 《Journal of inclusion phenomena and macrocyclic chemistry》1992,14(1):19-24
The paper deals with the relations between host lattices and guest molecules. Several types of interaction of the guest molecules and the host material are explained and some conclusions are made about the arrangement of various guest molecules in the van der Waals' gap. 相似文献
80.