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941.
942.
943.
944.
光谱法研究异丙甲草胺及其S-对映体与脲酶的相互作用机制 总被引:11,自引:0,他引:11
应用紫外差光谱和荧光光谱法研究了水溶液中酰胺类除草剂异丙甲草胺及其S 异构体与脲酶分子间的相互作用。结果表明 ,随着除草剂浓度的增加 (0 0~ 1 6 μmol·L-1 ) ,脲酶的紫外吸收光谱发生红移 ,吸收强度减弱。除草剂对脲酶的荧光均有猝灭作用 ,且静态猝灭是引起脲酶荧光猝灭的主要原因。从荧光猝灭结果求出了除草剂和脲酶的结合常数及结合位点数。异丙甲草胺 :K =1 4 9× 1 0 3 L·mol-1 ,n =0 84 ;S 异丙甲草胺 :K =2 2 2× 1 0 3 L·mol-1 ,n =0 89。 相似文献
945.
H. Fawcett S. Barlag H. Becker E. Belau T. Böhringer M. Bosman V. Castillo V. Chabaud D. Bucholz C. Damerell C. Daum G. De Rijk H. Dietl S. Gill A. Gillman R. Gilmore T. Gooch P. Gras Z. Hajduk E. Higon B. Hyams D. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé G. Polok J. Richardson M. Rozanska K. Rybicki H. Seebrunner U. Stierlin R. Tapper H. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(4):513-519
The production of the neutralK ? (892) resonances by 200 GeVK ? andπ ? has been studied over the kinematic range 0.0<x f<1.0 andp t 2 <5.0 GeV2. Longitudinal and transverse momentum distributions are presented. In addition the decay angular distributions inK ? fragmentation to \(\bar K^{0*} \) have been investigated. 相似文献
946.
N. M. Agababyan I. V. Ajinenko Yu. A. Belokopytov K. S. Belous H. Boettcher F. Botterweck M. M. Chapkin P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf K. Dziunikowska A. M. F. Endler A. Eskreys Z. C. Garutchava P. van Hal T. Haupt A. I. Katargin W. Kittel S. S. Megrabyan F. Meijers A. B. Micha?owska V. I. Nikolaenko K. Olkiewicz V. M. Ronjin R. Rosmalen H. M. T. Saarikko L. Scholten E. K. Shabalina J. Stepaniak O. G. Tchikilev V. A. Uvarov F. Verbeure R. Wischnewski S. A. Zotkin Y. V. Yarba EHS-NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(3):387-395
We report on a study of ρ0, ρ+, ω, \(\bar K^{*0} (892)\) andK *0 (892) inclusive production in π+ p interactions at 250 GeV/c, for ρ+, \(\bar K^{*0} (892)\) for the first time in a π+ p experiment. The data are compared withK + p data in the same experiment, with results of other experiments and with quark-parton models. Interesting differences are found between ρ+,0 and ω production. 相似文献
947.
The nuclear behaviour at high angular momenta is studied by γ-rays emitted in (HI, Xn) reaction. The study of very-high spin states in 153Ho via discrete-line γ-ray spectroscopy and a comparison between the partial decay schemes of 153Ho and the neighbouring 152Dy and 154Er nuclei are discussed in the context of the high spin structure. Second, we present comments on some phenomena observed at high spin states in 153Ho and 152Dy nuclei. 相似文献
948.
Based on the boson expansion and the so-called Jancovici-Schiff substitution,and approach has been developed to study the microscopic foundation of the interacting boson model.In this work an extension of the approach is made,thus one is able to treat the excitations of such system in which several neutron bosons,a proton boson and a proton-hole boson exist.With the consideration of the proton two-particle excitations we have studied the intruder quasi-rotational bands in double-even Sn nuclei.The Calculated results are compared with experiment and some features of the configuration mixture are discussed. 相似文献
949.
M. A. Koltunov M. Z. Kanovich Zh. D. Sakvarelidze 《Mechanics of Composite Materials》1976,12(3):380-384
An approximate method of analyzing plates of polymeric material under local loading is described. The state of stress and strain and the stability of the plate are investigated.Moscow Institute of Electronic Machine Building. Translated from Mekhanika Polimerov, No. 3, pp. 430–434, May–June, 1976. 相似文献
950.
Based on a newly developed theory (Lu and Weng, Acta Mech., in press) the high temperature behavior of an aircraft engine material is studied under combined stress state. Both monotonic and cyclic deformations are examined to uncover its stress-strain response, as well as its cyclic hardening and strain-ratchetting characteristics. Under a biaxial loading it is disclosed that tensile cyclic hardening is greatly magnified with a superimposed lateral tension, whereas the strain-ratchetting process is led to an enhanced, unsettling state with a superimposed lateral compression. The biaxial transient and steady-state creep strains have also been calculated. The results suggest that while a superimposed lateral tension will inhibit the creep deformation, a lateral compression can greatly promote the inelastic flow. To reflect the practical service conditions of an aircraft engine, the theory is further applied to examine the effect of loading frequency on the development of inelastic strains under concurrent thermal and mechanical loading. It is found that a more frequently flying aircraft will have a greater accumulation of creep strains and, consequently, a greater possibility of material damage in its engine components over the same total flying time. 相似文献