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V.?G.?KlyuevEmail author T.?L.?Maiorova A.?V.?Naumov V.?N.?Semenov 《Journal of Applied Spectroscopy》2005,72(4):552-557
CdS films, both pure and doped with the alkali metals Na and K, with Cl and without it, obtained by the aerosol pyrolysis
method from thiourea coordination compounds at a temperature of 250 to 500°C are investigated. The photoluminescence spectra
and the dependence of the luminescence intensity on the duration of exposure of samples to a high-power UV radiation have
been obtained. The doping of samples results in a tenfold increase in the intensity of the luminescence band in the visible
spectrum range (650–850 nm) as compared to pure samples of CdS. Upon irradiation of samples by high-power UV radiation for
1 h, no noticeable change in the intensity of luminescence of CdS films was observed. This is indicative of the stability
of the films under study against the action of UV radiation. The luminescent properties of the films, obtained pyrolytically
using thiourea coordination complexes, are determined by the synthesis conditions as well as by the chemical nature of the
original substances.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 4, pp. 509–513, July–August, 2005. 相似文献
124.
4-Phenyl-3,4-dihydro--carboline was prepared using the Bischler—Napieralski reaction on -phenyltryptamine.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 486–487, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
125.
Wittmer JP Meyer H Baschnagel J Johner A Obukhov S Mattioni L Müller M Semenov AN 《Physical review letters》2004,93(14):147801
The scaling of the bond-bond correlation function P1(s) along linear polymer chains is investigated with respect to the curvilinear distance s along the flexible chain and the monomer density rho via Monte Carlo and molecular dynamics simulations. Surprisingly, the correlations in dense three-dimensional solutions are found to decay with a power law P1(s) approximately s(-omega) with omega=3/2 and the exponential behavior commonly assumed is clearly ruled out for long chains. In semidilute solutions, the density dependent scaling of P1(s) approximately g(-omega(0))(s/g)(-omega) with omega(0)=2-2nu=0.824 (nu=0.588 being Flory's exponent) is set by the number of monomers g(rho) in an excluded volume blob. Our computational findings compare well with simple scaling arguments and perturbation calculation. The power-law behavior is due to self-interactions of chains caused by the chain connectivity and the incompressibility of the melt. 相似文献
126.
We present the results of experimental determination of the coefficients of laser radiation reflection (1 10.6 m and 2 1.06 m) from dielectric targets of complex chemical composition in vacuum with allowance for a regime of developed plasma formation. 相似文献
127.
Nevinsky GA Kanyshkova TG Semenov DV Vlassov AV Gal'vita AV Buneva VN 《Applied biochemistry and biotechnology》2000,83(1-3):115-130
The human milk secretory immune system is known to be the first line of protection for the newborn infant against various
pathogens. Secretory IgA (sIgA), the typical immunoglobulin found in secretions, can fight infections through many mechanisms.
Using different methods, we have shown that sIgA from the milk of healthy women possesses DNAse and RNAse activities. The
catalytic center is localized in the light chain of catalytic sIgA, while the DNA-binding center is predominantly formed by
its heavy chain. The enzymic properties and substrate specificity of catalytic sIgA distinguish it from other known DNases
and RNases. It is reasonable to assume, that the milk DNA- and RNA-hydrolyzing antibodies are capable not only of neutralizing
viral and bacterial nucleic acids by binding these antigens as well as by hydrolyzing them. The DNA-hydrolyzing activity of
Abs raises the possibility that these catalytic Abs may provide protective functions for the newborn through the hydrolysis
of viral and bacterial nucleic acids. 相似文献
128.
The configuration of the accelerating structure in the version of an electron-positron collider proposed earlier in [1] is optimized to increase the accelerating gradient for rf electromagnetic field strengths at the metal surface below the disruption threshold. 相似文献
129.
Starting from the general expression for the angular distribution of electrons produced through photoionization of spatially oriented molecules, simpler formulas for photoionization of linear molecules with an inversion center found in the Σ state, accompanied by the production of molecular ions in Σ and Π states, are obtained. For different geometric arrangements of the vectors determining the angular distribution, simple formulas are derived and their comparative analysis is made. It is shown that one can determine for different conditions of the experimental measurement of the angular dependences of ejected electrons the values of matrix elements and phase differences and separate the processes responsible for the production of ions in states with different symmetries. 相似文献
130.
K. A. Chernyshev V. A. Semenov L. B. Krivdin 《Russian Journal of Organic Chemistry》2013,49(3):379-383
Effect of solvation on the accuracy of DFT quantum-chemical calculations of 15N NMR chemical shifts of pyrrole, N-methylpyrrole, and pyridine was studied. The use of continuum model is sufficient to obtain consistent theoretical σN values for weakly polar aprotic solvents, whereas solvation effects in strongly polar and protic solvents should be taken into account in the explicit form. 相似文献