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1.
It is shown that a completely ionized, classical, Coulombian plasma, placed in an adiabatic enclosure, possesses a stationary state. At the same time, a plasma placed in a thermostat recombines through triple collisions, with a velocity satisfactorily accounted for by well-known theoretical results. The results obtained by numerical modeling have shown that, for a plasma placed in an adiabatic enclosure, the ergodic assumption is not valid. Various possible kinetic mechanisms, ensuring the existence of a stationary state of the adiabatically enclosed plasma, are considered.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 3–34, November, 1991. 相似文献
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From the multiple attenuated total internal reflection (MATIR) infrared spectrum of an aqueous KOH solution, the spectrum of the (HO)2H– ion, formed by a strong, symmetric H-bond, has been segregated. The spectrum of the analogous ion (CH3O)2H– has been segregated from the MATIR infrared spectrum of a solution of KOCH3 in methanol. The segregated spectra contain large numbers of individual bands that are not present in the spectra of the original components of the solution. This may be a consequence of strong interaction of vibrations of the proton in the central strong, symmetric hydrogen bond with vibrations of other groups in the ion.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1363–1366, June, 1991. 相似文献
5.
Kislina I. S. Maiorov V. D. Sysoeva S. G. Librovich N. B. 《Kinetics and Catalysis》2004,45(3):367-372
IR spectra of solutions of methanesulfonic acid in acetonitrile are recorded and analyzed at 30°C at methanesulfonic acid concentrations ranging from 0 to 100%. Molecular 1 : 1 complexes with the coordination of the acid proton at the nitrogen atom of the acetonitrile molecule are formed over a wide range of acid concentrations. When the base is in excess, the whole amount of the acid is bound in these complexes. In solutions with excess acid, the solvation of the 1 : 1 complexes by several methanesulfonic acid molecules produces associates containing a structure fragment in which the acetonitrile molecule acts as both the donor and acceptor of hydrogen bonds. Hydrogen bonds involving CH3 groups of acetonitrile can be formed when the 1 : 1 complexes are solvated by several acid molecules. 相似文献
6.
Ion–molecule interactions in the dichloroacetic acid–N,N-dimethylformamide system in the concentration range from pure acid to pure base at 30°C were investigated by multiple attenuated total internal reflectance IR spectroscopy. It was found that, depending on the ratio between components in solution, 1 : 1 or 2 : 1 acid–base complexes with strong hydrogen bonds are formed. With an excess of the acid, protonation of the base does not occur. The intensity of continuous absorption at 2000 cm–1 is characteristic of quasi-ionic pairs with strong symmetrical hydrogen bonds. However, along with a continuous component, the spectra exhibited individual sharp peaks, which are typical of molecular complexes. 相似文献
7.
The effect of 1,1,2,2-tetrachloroethane (TCE) on the IR spectra of HCl complexes withN,N-dimethylformamide (DMF) and 1-methyl-2-pyrrolidone (N-MP) with strong quasisymmetric hydrogen bonds was studied using Multiple Attenuated Total Reflection (MATR) IR spectroscopy.
The addition of TCE does not change the background absorption spectra, but results in a change in the extinction coefficients
of some bands of these complexes. The analysis of the spectra shows that the HCl−DMF complexes interact only with one molecule
of TCE, and the HCl−N-MP complexes interact with two molecules of TCE. It is shown that the neutral component of the system (TCE) has no effect
on the parameters of the strong quasi-symmetric H-bond in the complexes studied.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 956–960, May, 1997. 相似文献
8.
The method of multiple total internal reflection infrared spectroscopy (MTIRIRS) is used to study ion–molecular interactions in the system dichloroacetic acid–ethyl acetate in the range of concentrations from pure acid to pure base at 30°C. Depending on the ratio of components in the solution, molecular complexes with acid : base ratios of 1 : 1 or 2 : 1 are formed in the solutions. In the case of excess acid, base is not protonated and species with a strong symmetric hydrogen bond are not formed. It is shown that the absorption coefficient near 2000 cm–1 can be used to judge the type of the complex formed and the strength of a hydrogen bond in molecular complexes. 相似文献
9.
Alla Zablotskaya Izolda Segal Mikhail Maiorov Dmitry Zablotsky Anatoly Mishnev Edmunds Lukevics Irina Shestakova Ilona Domracheva 《Journal of magnetism and magnetic materials》2007
Water-soluble double-coated magnetic nanoparticles (NPs) containing cytotoxic decyldimethyl(β-dimethylaminoethoxy)silane methiodide (AA) molecule sorbed at biocompatible magnetic particles, which consist of magnetite pre-coated with oleic acid (OA), have been prepared. X-ray line profile broadening analysis was used for crystallite size determination. The method of magnetogranulometry has been used for determination of diameter of iron oxide magnetic core and magnetic properties of NPs prepared. In vitro cytotoxicity on monolayer tumor cell lines HT-1080 (human fibrosarcoma), MG-22A (mouse hepatoma) and normal mouse fibroblasts (NIH 3T3) has been studied. It was revealed that all the water-based colloidal solutions obtained are non-toxic and possess high NO-induction ability. 相似文献
10.
Vitaly Maiorov 《Advances in Computational Mathematics》2010,32(2):239-253
We study geometrical properties of the ridge function manifold \(\mathcal{R}_n\) consisting of all possible linear combinations of n functions of the form g(a· x), where a·x is the inner product in \({\mathbb R}^d\). We obtain an estimate for the ε-entropy numbers in terms of smaller ε-covering numbers of the compact class G n,s formed by the intersection of the class \(\mathcal{R}_n\) with the unit ball \(B\mathcal{P}_s^d\) in the space of polynomials on \({\mathbb R}^d\) of degree s. In particular we show that for n?≤?s d???1 the ε-entropy number H ε (G n,s,L q ) of the class G n,s in the space L q is of order nslog1/ε (modulo a logarithmic factor). Note that the ε-entropy number \(H_\varepsilon(B\mathcal{P}_s^d,L_q)\) of the unit ball is of order s d log1/ε. Moreover, we obtain an estimate for the pseudo-dimension of the ridge function class G n,s. 相似文献