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101.
The temperature shift of the neutrino mass in a constant magnetic field is calculated within the framework of the Weinberg-Salam model. The cases of weak field and low and high temperatures are considered. The contribution to the anomalous magnetic moment of the neutrino is determined. The imaginary component of the mass correction describing the reaction of decay and W-boson formation is analyzed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 3–6, December, 1987. 相似文献
102.
103.
A. N. Ponomarev E. F. Abdrashitov D. A. Kritskaya V. Ch. Bokun E. A. Sanginov Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2017,53(6):589-607
Methods for the preparation of composite ion-exchange membranes from polymer (polyvinylidene fluoride (PVDF), ultrahigh molecular weight polyethylene (UHMWPE), and polypropylene (PP)) matrices were considered. Polystyrene (PS) was introduced in the matrices by thermal polymerization of the monomer followed by sulfonation of the implant. The fundamentals of membrane synthesis from industrial polytetrafluoroethylene (PTFE, Teflon F-4) films by thermal polymerization of styrene in a film stretched in a monomer solution followed by sulfonation of incorporated PS were described. The literature on radiation- chemical synthesis of composite ion-exchange membranes based on polymer matrices with embedded polystyrene and its subsequent sulfonation was analyzed. Some problems of the kinetics and mechanism of thermal implantation of PS into various polymer matrices under different conditions were discussed. The physicochemical characteristics, structure, and transport properties of the membranes synthesized by thermal implantation of PS were reported. The obtained membranes were tested in low-temperature fuel cells. 相似文献
104.
105.
From the feeding of young plants of Strychnos nux-vomica with [14C]-1-and [14C]-2-acetate it could be deduced that the C-atoms 22 and 23 were derived from acetate. [14C]-2-mevalonate, [14C]-2-geraniol and [14C]-2-geranyl pyrophosphate were also incorporated into strychnine. The distribution of radioactivity in the «mevalonate-strychnine» was in agreement with the monoterpenoid hypothesis. Feeding experiments especially with [14C]-tryptophane showed that the main production centre of the alkaloid lay in the roots and that only a small part of it was carried to the leaves. Tritium labelled WIELAND GUMLICH aldehyde as well as N(a)-[14C]-1-acetyl WIELAND GUMLICH aldehyde were not converted into strychnine by S. nux-vomica. 相似文献
106.
The electroreduction of camphorquinone in DMF, at mercury electrodes, was investigated by a variety of techniques. In DMF, in the absence of proton donor, camphorquinone exhibits two one-electron waves: the first, a one-electron reversible wave to be due to a reversible charge transfer without a coupled chemical reaction. After the first charge transfer, the semidione anion radical is reduced to the dianion. The irreversibility of the second wave derives from a fast irreversible protonation of the dianion. A wide variety of changes in behaviour is observed in the reduction of camphorquinone as increasing amounts of benzoic acid are added: a new two-electron irreversible wave appears at a potential less negative than the original wave. A proton donor to substrate ratio of 2 is required to completely suppress the two original waves. A mechanism for the electroreduction of camphorquinone is proposed and discussed on the basis that the prewave current is controlled by the diffusion of the undissociated acid species and that the undissociated acid, rather than the solvated proton, takes part in the protonation, prior to the charge transfer. 相似文献
107.
Series of variously sustituted amides of 2-sulfonamido-4,5-dimethoxyphenylacetic acid have been prepared. The reaction of diethylamine, piperidine, morpholine and bis(2-chloroethyl)amine with carbo-methoxymethyl-3,4-dimethoxybenzenesulfonyl chloride produced the corresponding sulfonamido derivatives. Acid hydrolysis of the latter and action of thionyl chloride gave the chlorocarboxymethyl-benzenesulfonamides. The acid chlorides of the sulfonamides were transformed to the 2-carboxamido-bis(2-chloroethyl)methylbenzenesulfonamides with bis(2-chloroethyl)amine. These agents were tested in L-1210 and P-388 leukemias and were found not to possess antitumor activity in these two transplantable tumor lines. 相似文献
108.
H. K. Barrenscheen Margarete Frey F. Feigl L. T. Fairhall M. Settimj D. Ganassini A. Necke H. Müller Ch. Badham H. B. Taylor G. Moillère F. Weyrauch St. Litzner F. Grendel N. Schoorl H. Begemann A. Berat G. Widmark B. Vahlquist E. M. P. Widmar S. L. Oerskov J. P. Gregersen P. Iversen H. W. Mook D. D. van Sluke W. M. Kirjan W. C. Stadie E. C. Ross K. Lang H. Waelsch Gertrud Klepetar I. St. Lorant L. Kopetz J. W. Heim W. W. Práwdicz-Neminski Z. Babitsch J. F. Reith Th. von Fellenberg R. G. Turner Mina Z. Weeks A. Castille V. Henri 《Analytical and bioanalytical chemistry》1934,98(3-4):147-160
109.
110.
H. -H. Lei P. P. T. Sah und Ch. Shih 《Fresenius' Journal of Analytical Chemistry》1937,109(3-4):135-136
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