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1.
Consideration is given to the special features of the excitation of spectra of metals (Ag, Au, Fe, Hg, Pt, and Sb) that manifest
themselves in investigating spectral sources with combined glow discharge (glow discharge and capillary discharge). It is
established that the proposed method for introducing a substance into a plasma makes it possible to realize two fundamentally
different regimes: without evaporation and with complete evaporation and matrix atomization. It is shown that a spectral source
of combined glow discharge with a nonequilibrium plasma has significant advantages for the most important analytical characteristics
over quasi-equilibrium combined discharge at atmospheric pressure. The gold and platinum sensitivity in combined glow discharge
is 10−7%, and the reproducibility of spectral determinations is 0.001–0.100, depending on the measurement range. A fractional separation
of elements that makes it possible to analyze the phase composition of substances, particularly metals, with high sensitivity
is revealed in glow discharge.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 143–147, March–April, 1997. 相似文献
2.
Raman scattering in glasses is investigated theoretically. The experimental Raman spectra of glasses exhibit a low-frequency peak (at ~10 cm?1) that, as a rule, is attributed to vibrational modes of nanometer-sized structural units (nanocrystallites). It is established that the elastic moduli of nanocrystallites must necessarily be dependent on their sizes due to the Laplace pressure effect. A theory of the low-frequency peak is constructed using a realistic size distribution function of nanocrystallites with allowance made for the Laplace pressure effect and the dissipation of vibrational energy. Within this theory, the shape of the low-frequency peak and its evolution with temperature can be analyzed quantitatively. The proposed approach offers a physical interpretation of the experimental data and provides insight into the relation of the characteristic nanocrystallite sizes to the elastic moduli and surface tension coefficients of materials. 相似文献
3.
4.
We study the problem of evaluation of the probability of ruin of an insurance company for infinitely many steps in the case
where the company can invest its capital to bank deposits at any time. As a distribution of the amounts of claims to the insurance
company, we use the gamma-distribution with the parameters n and α.
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 4, pp. 447–457, April, 2007. 相似文献
5.
Gavrilov K. N. Bondarev O. G. Polosukhin A. I. Lyubimov S. E. Tzarev V. N. 《Russian Journal of Coordination Chemistry》2002,28(2):143-145
Optically active amidophosphite with the peripheral imino group (R)-(Et2N)2POCH2CH(Et)N=CHPh is synthesized through one-stage phosphorylation of the corresponding imino alcohol. Its reaction with [Rh(CO)2Cl]2 (at P : Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl]. Structures of the compounds are determined by IR, 31P, and 13C NMR spectroscopy, mass spectrometry, and polarimetry. 相似文献
6.
B. V. Bondarev 《Ukrainian Mathematical Journal》1991,43(3):279-286
The first initial-boundary problem for a parabolic equation with a small parameter under external action described by some random process satisfying an arbitrary condition of weak dependence is considered. Averaging of the coefficients over a time variable is carried out. The existence of a generalized solution for the initial stochastic problem as well as for the problem with an averaged equation which turns out to be deterministic is assumed. Exponential bounds of the type of the well-known Bernstein inequalities for a sum of independent random variables are established for the probability of the deviation of the solution of the initial equation from the solution of the averaged problem.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 3, pp. 315–322, March, 1991. 相似文献
7.
B. V. Bondarev 《Ukrainian Mathematical Journal》1991,43(4):279-286
The first initial-boundary problem for a parabolic equation with a small parameter under external action described by some random process satisfying an arbitrary condition of weak dependence is considered. Averaging of the coefficients over a time variable is carried out. The existence of a generalized solution for the initial stochastic problem as well as for the problem with an averaged equation which turns out to be deterministic is assumed. Exponential bounds of the type of the well-known Bernstein inequalities for a sum of independent random variables are established for the probability of the deviation of the solution of the initial equation from the solution of the averaged problem.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 43, No. 3, pp. 315–322, March, 1991. 相似文献
8.
B. V. Bondarev 《Ukrainian Mathematical Journal》1992,44(8):915-923
The first initial boundary value problem is considered for a hyperbolic equation with a small parameter for an external action described by some stochastic process satisfying some of the conditions of weak dependence. Averaging of the coefficients over the temporal variable is conducted. The existence is assumed of a unique generalized solution both for the initial stochastic problem and for the problem with an averaged equation, which turns out to be deterministic. For the probability of deviation of a solution of the initial equation from the solution of the averaged problem, exponential bounds are established of the type of S. N. Bernshtein inequalities for the sums of independent random variables.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 8, pp. 1011–1020, August, 1992. 相似文献
9.
10.
Russian Journal of General Chemistry - Linear Fisher classification functions, canonical linear discriminant functions, and trees (rules) for classification and prediction of the stability of... 相似文献