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651.
V. M. Dziomko G. N. Ruchkina Yu. S. Ryabokobylko E. E. Orlova R. V. Poponova 《Chemistry of Heterocyclic Compounds》1991,27(3):292-295
The reactions of N-monomethylated 1,8,9,20-tetrahydro-3,6-dimethyl-1,8-diphenyldibenzo[c,m]dipyrazolo[3,4-f:4,3-j]-[1, 2, 5, 8, 9, 12]hexaazacyclotetradecene with Ni(II), Pd(II), and Cu(II) salts were studied. It is shown that the introduction of an N-substituent leads to a significant change in the chemical properties of the macroheterocyclic ligand.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 360–364, March, 1991. 相似文献
652.
M. G. Ezernitskaya B. V. Lokshin T. Yu. Orlova V. N. Setkina S. Nunziante Cesaro 《Russian Chemical Bulletin》1994,43(11):1837-1840
FTIR spectra have been studied for staircase cyclopentadienyl complexes comprising two or three metal carbonyl fragments bound by the metal-carbon bond Cp(CO)2Fe-CpmMn(CO)3 (1), Cp(CO)2Fe-CpmFe(CO)2CH2Ph (2), Cp(CO)2Fe-Cpm(CO)2Fe-CpmMn(CO)3 (3), Cp(CO)2Mo-Cpm(CO)2Fe-CpmMn(CO)3 (4), Cp(CO)3W- Cpm(CO)2Fe-CpmMn(CO)3 (5), Cp(CO)2Fe-Cpm(CO)2Fe-BmCr(CO)3 (6), Cr(CO)3Bm-CpmFe(CO)2CH2Ph (7), where Cp = 5-C5H5, Cpm = 15-C5H4, Bm = 16-C6H5, as well as mononuclear model complexes Cp(CO)2Fe(CH)2Ph (8), CpMn(CO)3 (9), and (6-C6H6)Cr(CO)3 (10). The spectra were interpreted on the basis of the local symmetry of each metal carbonyl center. The positions of vCOs are determined by the mutual electronic effect of each center. CpmM(CO)n groups are strong electron acceptors and cause an increase in vCOs of adjacent M(CO)n groups. Cp(CO)nM groups, being electron donors, cause a decrease in the frequencies of neighboring groups. In trinuclear complexes, the frequencies of the central Fe(CO)2 group are not changed much due to the compensation of donor and acceptor influences of two neighboring substituents.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1948–1951, November, 1994.This project was supported by the Russian Foundation for Basic Research (project code No. 93-03-18592). 相似文献
653.
A. I. Lytkin N. V. Chernyavskaya T. D. Orlova V. M. Nikol’skii 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(7):1061-1065
The heat effects of dissociation of N-(carboxymethyl)aspartic acid were determined calorimetrically at 298.15 K and various ionic strength values. The standard thermodynamic characteristics of dissociation of the complexone at fixed and zero ionic strengths were calculated. 相似文献
654.
T. N. Orlova E. E. Afanas’eva E. N. Afanas’ev I. S. Tyumentseva N. F. Vasilenko 《Moscow University Chemistry Bulletin》2008,63(3):176-178
The composition of native aluminosilicate used to prepare, by means of chemical modification, a functionalized ferromagnetic organosilicon sorbent suitable for immobilizing biologically active substances was studied. 相似文献
655.
656.
The process of activation of an angiotensin-converting enzyme by ionizing radiation was studied in terms of a kinetic model suggesting the existence of at least one activated form of the enzyme. The kinetic decaying oscillations induced by an exciting force were obtained and analyzed. It was shown that the probability of a periodic process is lower than that of the appearance and reactions of one activated form of the enzyme. 相似文献
657.
I. Yu. Kargapolova K. S. Shmuilovich N. A. Orlova M. M. Shakirov T. V. Rybalova V. V. Shelkovnikov 《Russian Chemical Bulletin》2008,57(2):412-417
The reactions of α-pentafluorophenylpyrylium salts with hydroxylamine in ethanol afford isoxazoline derivatives and/or pyridine
N-oxides depending on the steric characteristics of the substituent in the second α position. The structure of 2-hydroxy-2-pentafluorophenyl-4-phenyl-2,3,5,6,7,8-hexahydroquinoline
1-oxide, which was synthesized by the reaction of 2-pentafluorophenyl-4-phenyl-5,6,7,8-tetrahydrobenzopyrylium perchlorate
with NH2OH, was established by X-ray diffraction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 402–407, February, 2008. 相似文献
658.
T. A. Chubar' M. A. Orlova I. G. Gazaryan V. A. Fechina E. A. Mareeva O. V. Ignatenko P. A. Savitskii A. M. Rozhkova V. I. Tishkov 《Russian Chemical Bulletin》1999,48(12):2330-2333
The stability of recombinant wild-type horseradish peroxidase and its tryptophan-less mutant Trp117Phe toward γ-radiation
was studied. The absence of tryptophan in the enzyme molecule results in a certain stabilization, which is manifested as the
absence of the initial drop in activity and appearance of a lag period for doses of up to 45 Gy. Contrary to the wild-type
enzyme, the dose response of the mutant is almost independent of the nature of the substrate used to measure the catalytic
activity; this indirectly indicates that Trp117 participates in the oxidation of substrates. Pretreatment of the wild-type
recombinant enzyme with hydrogen peroxide destabilizes the enzyme towards irradiation, while the same procedure for the mutant
enzyme has virtually no effect on the dose response curve. This suggests the modification of Trp117 in the oxidation of the
native enzyme with H2O2 in the absence of electron-donor substrates, which is the modification of Trp171 in the recombinant lignin peroxidase.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2355–2358, December, 1999. 相似文献
659.
Michael Zuykov Emilien Pelletier Claude Rouleau Leonid Popov Scott W. Fowler Marina Orlova 《Mikrochimica acta》2009,167(3-4):173-178
Autoradiography was used to identify α-track distributions in a series of shell sections from live mussels Dreissena polymorpha Pallas and dissected shells of dead mussels obtained from laboratory experiments using relatively high concentrations of 241Am in the exposure media, a required condition for successful use of this autoradiographic technique. A comparable distribution of α-tracks was recorded on autoradiographs from both live and dead shells suggesting that metabolism does not lead to any sizable changes in the process of 241Am adsorption (present in the extrapallial fluid) onto the inner surface of shell. Autoradiographs showed a preferential accumulation of 241Am in the organic periostracum, whereas the outer and inner shell layers were characterized by a relatively low α-tracks density. No α-tracks were observed in the central part of the shell in any of the samples. These observations will be useful for the development of a general model to explain bioaccumulation and biosorption processes of radionuclides into mollusk shells. 相似文献
660.
The deformation behavior of high-chromium steel (0.4%C–0.6%Si–0.55%Mn–12.5%Cr) of martensitic structure upon quenching and
of sorbitic structure upon high-temperature tempering has been investigated. Each of the states is shown to be represented
by a particular stress-strain curve. The stress-strain curve for the steel in the martensitic state consists of a single linear-hardening
stage, whereas in the sorbitic state, it exhibits a three-stage deformation pattern. The plastic flow of the examined material
in the two states has been found to be of a localized character. The evolution of localized-strain center distributions follows
the law of plastic flow, i.e., it depends on the deformation stages in the stress-strain curve. The fracture process is determined
by the kinetics of the localized-strain centers in the final (prefracture) deformation stage in the stress-strain curve. 相似文献