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1.
L. S. Azhgirey V. V. Arkhipov S. V. Afanasiev V. K. Bondarev V. N. Zhmyro L. S. Zolin V. I. Ivanov A. Yu. Isupov A. A. Kartamyshev V. A. Kashirin V. I. Kolesnikov V. A. Kuznetsov V. P. Ladygin N. B. Ladygina A. G. Litvinenko S. G. Reznikov P. A. Rukoyatkin A. Yu. Semenov I. A. Semenova G. D. Stoletov G. Filipov A. N. Khrenov N. P. Yudin 《Physics of Atomic Nuclei》2003,66(4):690-699
The invariant differential cross section, the tensor analyzing power A yy , and the vector analyzing power A y for the reaction 9Be(d, p)X are measured at an initial deuteron momentum of 4.5 GeV/c and a proton detection angle of about 80 mrad. The data obtained for the differential cross section are consistent with the results of measurements at 3.5 and 5.78 GeV/c and a proton emission angle of 2.5°. The values found for the tensor analyzing power A yy are compared with similar data obtained previously for the deuteron-fragmentation process occurring on a carbon target at various values of the initial deuteron momentum and leading to proton emission at zero angle. The data on the differential cross section for the reaction 9Be(d, p)X can be satisfactorily described within the relativistic impulse approximation by using standard deuteron wave functions; however, the approach based on this conceptual framework proves to be inadequate in dealing with data on the tensor analyzing power. These results indicate that it is necessary either to change the method for describing the relativistic deuteron or to take into account additional mechanisms. 相似文献
2.
3.
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
4.
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
5.
6.
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
7.
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
8.
Recent advances in time-dependent density functional theory (TDDFT) have led to computational methods that can predict properties of photoexcited molecules with satisfactory accuracy at comparably moderate cost. We apply these methods to study the photophysics and photochemistry of 4-(dimethyl)aminobenzonitrile (DMABN). DMABN is considered the paradigm of photoinduced intramolecular charge transfer (ICT), leading to dual fluorescence in polar solvents. By comparison of calculated emission energies, dipole moments, and vibrational frequencies with recent results from transient spectroscopy measurements, a definitive assignment of the electronic and geometric structure of the two lowest singlet excited states of DMABN is possible for the first time. We investigate the mechanism of the ICT reaction by means of minimum energy path calculations. The results confirm existing state-crossing models of dual fluorescence. Our study suggests that analytical TDDFT derivative methods will be useful to predict and classify emissive properties of other donor-acceptor systems as well. 相似文献
9.
It has been shown that under high-power laser UV irradiation (I = 108–1010 W/cm2, λ = 266 nm, τp = 30 ps) water becomes ionized by a two-photon mechanism to form some free radicals including the hydrated electron e?aq. 相似文献
10.
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