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11.
A. G. Khorti E. N. Glibin Z. I. Korshunova O. F. Ginzburg A. D. Ziv V. V. Nesterov O. I. Kurenbin 《Russian Chemical Bulletin》1991,40(10):1983-1986
The retention of crown compounds in reverse-phase HPLC is determined by their ability to bind to cations present in the eluent. The dependence of the retention of crown compounds on concentration of the binding cation has a break. This enables the stability constant of the crown-compound-cation complex to be calculated. The retention of the antitumor antibiotic actinomycin D in 75% MeOH is demonstrated to depend on [Na+] and not on [K+] for concentrations of the latter from 10–6 to 10–1 M.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2265–2269, October, 1991. 相似文献
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On the basis of the intermolecular potentials data structural phase transitions in polymer crystals (polyethylene) are described. By using the meanfield approximation, the theories of premelting transitions for paraffin crystals and conformational melting of polyethylene crystals were developed. The dependence of temperatures of such transitions upon chain length was calculated and rather good agreement with experimental data was shown.Dedicated to Prof. Dr. W. Pechhold on the occasion of his 60th birthday 相似文献
15.
A. P. Voznyakovskii B. M. Ginzburg D. Rashidov D. G. Tochil’nikov Sh. Tuichiev 《Polymer Science Series A》2010,52(10):1044-1050
The effect of modifying additives based on detonation nanodiamonds on the tribological characteristics of polyurethane rubber
is studied. Introduction of modifying additives based on detonation nanodiamonds (0.5 wt %) leads to a marked improvement
in the antifriction and wear-resistance characteristics under conditions of boundary sliding friction for steel and for lubrication
with water. The attained tribological characteristics (total energy loss for friction, weight loss of polymer during tribological
contact, maximum admissible working pressure) are well (∼300%) above the corresponding characteristics of foreign analogs.
Changes in the tribological characteristics of the formed nanocomposite material are observed, but the elastic and strength
characteristics remain unchanged. 相似文献
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I. F. Ginzburg 《Physics of Particles and Nuclei Letters》2012,9(9-10):678-685
In many models stability of dark matter particles D (with mass M D ) is ensured by a new conserved quantum number which we call the D-parity. We consider models which also contain charged D-odd particle D ± (with mass M ±). We study the process e + e ? ?? D + D ? followed by decay of D ± to D and gauge bosons W (either on-shell or off-shell). Measuring the end points of the energy distribution of W??s would determine M D and M ±. However, the hadron mode of W decay would lead to low precision in this measurement. while the information from the lepton mode looks incomplete. I show that it is sufficient to measure the energy distribution of a single lepton (for definiteness ??) in the process e + e ? ?? ?? + 2jets + large missing E T . The well identified singularities in this distribution allow for determination of M D and M ± with a high precision. After that, measuring the corresponding cross section will allow one to determine the spin of D particles. 相似文献
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Alexandr Kh. Plyamovatyi Raviya M. Mukhamadeeva Vasily A. Milyukov Oleg G. Sinyashin Alexandr E. Vandyukov Roald R. Shagidullin Allan G. Ginzburg Vyacheslav I. Sokolov 《Heteroatom Chemistry》1995,6(2):177-181
FT-IR spectroscopy and a special mathematical program were used for the real-time monitoring of the mechanistic path of the reaction of S-ethyl-N,N-tetraethyldiamidothiophosphite with [CpMn(CO)-2NO]+BFequation/tex2gif-stack-3.gif. The formation of a few intermediates is described. 相似文献
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A theory of free-electron lasers fed a sequence of short electron pulses is developed. It is assumed that the group velocity
of the electromagnetic pulse that develops in the cavity is the same as the translational velocity of the particles, and the
repetition period of the electron pulses equals the transit time of the electromagnetic radiation in the cavity. Under these
conditions of group synchronism, the principal factors governing the feasibility of establishing a stationary pulsed lasing
regime are found to be the dispersive spread of the electromagnetic pulse and the channeling properties of an electron bunch.
The conditions for self-excitation are found, and the characteristics of the stationary lasing regimes are determined assuming
that the cavity has a high Q and using a parabolic equation for the evolution of the electromagnetic pulse shape.
Zh. Tekh. Fiz. 69, 78–83 (February 1999) 相似文献