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81.
In the framework of noncommutative geometry we describe spinor fields with nonvanishing winding number on a truncated (fuzzy) sphere. The corresponding field theory actions conserve all basic symmetries of the standard commutative version (space isometries and global chiral symmetry), but due to the noncommutativity of the space the fields are regularized and they contain only a finite number of modes.Part of the Project P8916-PHY of the Fonds zur Förderung der wissenschaftlichen Forschung in Österreich. 相似文献
82.
Precise values of energies and widths of low-lying resonances in some rare-gas atom systems (Ar-Ar, Ne-Kr, Ne-Xe) are reported. 相似文献
83.
A. Brablec J. Janča V. Kapička D. Trunec Yu. Chutov V. Pikozh 《Czechoslovak Journal of Physics》1996,46(6):587-594
An expansion of finite plasma clots into the background neutral gas is studied numerically. The presented model includes the quasineutrality violation as well as the interpenetration of plasma and neutral gas at the boundary of the plasma. We estimate the region of plasma parameters where the model is correct. Space distributions of main plasma parameters, cooling of electrons and the process of inter-penetration of the plasma and the neutral gas are analysed as well as an empiric formula for electron temperature is found. Finally, it is shown that the most intensive plasma-gas inter-penetration occurs in the case where the initial plasma and gas densities are the same. 相似文献
84.
85.
J. L. Vučina 《Journal of Radioanalytical and Nuclear Chemistry》1996,214(1):29-39
The effect of the preparation conditions on the in vitro stability of99mTc (Sn)-pyrophosphate kit solution has been examined. To extend the shelf-life of the preparation, different methods of protection were tested. Nitrogen purging stabilizes the kit for at least 6 h after labeling when the content of99mTc-pertechnetate raises to about 5%. However, this method is ineffective in the presence of hydrogen peroxide. The protecting ability of two chemicals was also determined. Gentisic acid gave good results. In the presence of 50 g of gentisic acid per ml of the kit the content of pertechnetate was 1–2% throughout the examined time interval. To eliminate the influence of hydrogen peroxide (6 g per ml of the kit) about 100 g of gentisic acid is needed. N, N-diphenyl-p-phenylenediamine (DPPD) performs some protecting effect only when used in the samples protected by nitrogen purging. However its protecting ability is lower that in the case of gentisic acid. 相似文献
86.
The paper describes magic labelings of type (1,1,1) for two classes of graphs, which are obtained by a combination of vertex, edge and face labelings. 相似文献
87.
88.
A new self-assembled and highly oriented one-dimensional single-crystal nanostructure of WO3 with hexagonal form was successfully prepared by a mild, solution-based colloidal approach. 相似文献
89.
Zusammenfassung Die schon früher beschriebene gasvolumetrische Methode zur N-N-Gruppenbestimmung durch Oxydationsaufschluß mit Chromsäure wurde zur Bestimmung des heterocyklischen Stickstoffes in Indazolinonderivaten mit Erfolg benützt und dadurch weiter die allgemeine Anwendbarkeit der Methode bestätigt. Enthält die Substanz gleichzeitig Amino- oder Nitrogruppen, können diese aus derselben Einwaage als Ammoniak bzw. Salpetersäure bestimmt werden.
XXVII. Mitteilung, siehe1. 相似文献
Analytical aspects of the oxidation of organic nitrogen compounds with chromic acid
Summary The gas volumetric method for determining N-N groups by oxidative fusion with chromic acid (which has already been described previously) was successfully employed to determine the heterocyclic nitrogen in indazolinone derivatives. The general applicability of the method was thereby confirmed. If the substance contains amino or nitro groups at the same time, these can be determined in the same sample as ammonia or nitric acid.
XXVII. Mitteilung, siehe1. 相似文献
90.
The reaction of N-phenylsulfonylbenzoxazolone with amines was investigated in order to study the mechanism of the reaction between aryloxazolones and amines. The sulfonyl group accelerates the reaction considerably. The structure of 2-(phenylsulfamido)phenyl esters of the corresponding N-substituted carbamic acids was assigned to the products on the basis of the IR spectra and alternative synthesis. The reaction with secondary aliphatic amines (dimethyl- and diethylamine)proceeds considerably more slowly and results in the formation of 2-(phenylsulfamido)phenol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1333–1336, October, 1971. 相似文献