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991.
The Gelcode color-based silver staining system, an improved formulation based on the original publication by Sammons et al. (Electrophoresis 1981, 2, 141-147) has been adapted to automated rapid staining in the PhastSystem Development Unit. The use of elevated temperatures in the fixation, washing, staining, and stabilization steps of the protocol reduces the total time of the process from 18 h to 1 h. The limit of detection, which is at least tenfold more sensitive than the silver staining protocol recommended for the PhastSystem, corresponds to 0.05-0.1 ng of protein per band. The method is applicable to both one- and two-dimensional polyacrylamide gels. 相似文献
992.
993.
The theta temperature for the system poly(o-chlorostyrene)-methyl ethyl ketone has been determined as 24·5°. The samples used in the determination were prepared by radical polymerization. The dependence of intrinsic viscosity on molecular weight has been measured in methyl ethyl ketone at 24·5° and found to be . The ratio 〈s=2〉/M was found, by light scattering, to be 5·60 × 10?18 cm2. Analysis of the solution properties indicates that the Kurata-Yamakawa theory is valid in the vicinity of the Flory temperature (UCST). 相似文献
994.
Conclusions Silver perchlorate catalyzes the decomposition of aqueous hydrogen peroxide solutions and, contrary to the literature data, does not form the salt AgClO5 in either ethanol medium or in diethyl ether medium. Silver perchlorate, the same as other perchlorates, does not form molecular compounds with hydrogen peroxide at 0°C.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2640–2641, November, 1974. 相似文献
995.
C.S. Dimbylow I.J. McColm C.M.P. Barton N.N. Greenwood G.E. Turner 《Journal of solid state chemistry》1974,10(2):128-136
Crystal chemistry and phase relations for the bronze-forming region of the EuWO system have been investigated. A bronze EuxWO3 is stable up to 1000°C when x ? 0.125 and in the region 0.085 ? x ? 0.125 the symmetry is cubic. A tetragonal bronze exists at x = 0.05, and an orthorhombic bronze with a structure closely related to the orthorhombic form of WO3 exists below x = 0.01. Mössbauer spectra at room temperature and at 80 K indicate that in all these phases the europium is highly ionized as Eu(III) with no electron localization to give (EuII) even at low values for x. The decomposition products of the bronzes have been established, and the Mössbauer parameters for the highly nonstoichiometric tungstates EuxWO4 were determined. Both Eu(II) and Eu(III) resonances were obtained, and a cation vacancy model for EuxWO4 was found to fit the data best. In conformity with the foregoing data, a sample of composition “Eu2W2O7” was found not be be a pyrochlore but to comprise a mixture of Eu6WO12, EuxWO4, and W. The phase relationships for the europium bronze system EuxWO3 are compared with those of other ionic bronzes NaxWO3, LixWO3, and AlxWO3. 相似文献
996.
Conclusions In our view, the material examined in the present review indicates that, in spite of the appearance of more accurate methods of calculating the electronic structure and the increasing possibilities provided for their realization for fairly complex systems, the applied value of simple semiempirical methods, in particular the CNDO method, is far from exhausted. In the near future, semiempirical calculations will probably provide the chief means of studying the electronic structures of complex molecules, by becoming accessible to an increasing circle of chemists.Leningrad State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 17, No. 3, pp. 549–577, May–June, 1976. 相似文献
997.
Conclusions The reactions of 1-(3-chloropropyl)silatrane with potassium O,O-diethyl dithiophosphate gave O,O-diethyl-S-(1-silatranylpropyl) dithiophosphate. O,O-Diethyl- and O,O-dipropyl-S-(1-silatranylmethyl) dithiophosphates were synthesized by the tranesterification of O,O-diethyl-and O,O-dipropyl-S-(trimethoxysilylmethyl) dithiophosphates by tris(2-hydroxyethyl)amine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1882–1884, August, 1987. 相似文献
998.
Zh. V. Bren' V. A. Bren' L. M. Sitkina V. I. Minkin 《Chemistry of Heterocyclic Compounds》1979,15(1):56-59
A number of phenylmercury derivatives of 3-hydroxymethylene- and 3-aminomethylene-substituted 1-methyloxindoles, 1-indanones, and 1,3-indanediones were synthesized. It is shown that the preferred tautomeric structures of the potentially metallotropic and prototropic hydroxymethylene keto (hydroxy vinyl aldehyde) derivatives of the indicated compounds and 3-hydroxybenzo[b]-2-formylthiophene coincide precisely. An aminomethylene structure with an N-H bond is realized for the phenylmercury derivatives of the corresponding azomethines in all cases.Communication 28 from the series Benzenoid-Quinoid Tautomerism of Azomethines and Their Structural Analogs. See [1] for communication 27.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 65–68, January, 1979. 相似文献
999.
Yu. D. Perfiliev M. I. Afanasov A. M. Babeshkin 《Journal of Radioanalytical and Nuclear Chemistry》1985,93(1):29-35
The energy absorbed by immediate surrounding of disintegrating119mSn nuclei have been estimated by comparing the Mössbauer emission spectra of119Sn in some tin compounds with the absorption spectra of the same substances after -irradiation and by simple calculations of Auger electrons energy losses. The results obtained indicate that the observed post-effects of the119mSn decay are due to self-radiolysis and other processes, whose contributions depend on the individual properties of the matrices. 相似文献
1000.
An extended average energy (EAE) calculation of the 2s2 and 2p21S resonance state energies of two-electron atoms is carried out. We take the bare-nucleus hamiltonian as the initial approximation and treat the zeroth-order degeneracy by van Vleck perturbation theory, For both H? and He the lower state energies agree quite well with experiment while the upper state is about 1–2 eV too high. Our remits for He are comparable in accuracy to those obtained by the 1/Z Hartree—Fock perturbation method. A brief concluding discussion of ways to improve the simple EAE technique is presented. 相似文献