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21.
The enthalpies of the interaction of the L-β-phenyl-α-alanine anion with the Ni2+ ion in aqueous solution were measured by calorimetry for the ionic strength I = 0.5, 1.0, and 1.5 (KNO3 as a supporting electrolyte) at 298.15 K. The thermodynamic parameters of the formation of Ni(II) complexes with phenylalanine in aqueous solution were calculated. The effect of the ligand structure on the thermodynamic parameters of complexation reactions in solution was discussed. 相似文献
22.
A system of nonlinear differential equations of the type on a domain of ?n is studied. Functional relations between the fj's, j = 1, …, n, and other necessary conditions are deduced when at each point of the domain the system has a manifold of local solutions. A structure theorem, that makes possible to reduce the problems of the system, e.g. the global solvability of it, to the corresponding questions for a connection of the type ?z?w = g(z, w) in a fibre bundle over a Riemann surface is proved, and through this reduction we obtain theorems of identity, extension, global factorization, and so on, for the solutions of the system. As an example, a system of nonlinear differential equations of the type is studied and its global solutions are constructed. 相似文献
23.
S. N. Shtykov T. Yu. Rusanova T. D. Smirnova D. A. Gorin 《Journal of Analytical Chemistry》2004,59(2):175-178
Deposition conditions are studied, and a Langmuir–Blodgett film (LBF) based on the benzopurpurin 4B indicator immobilized in the polyamide acid salt matrix is obtained. The protolytic properties of the indicator are studied in water, micelles of cationic and nonionic surfactants, and LBFs. It is shown that, in going from water to the cited micelles and LBFs, pK
ind is shifted to the acidic region by 3.25, 1.18, and 2.30 pH units, respectively. The possibility of using the produced LBF as the sensing element of an optical sensor for the determination of the acidity of solutions in the pH range 1–0 is demonstrated. The LBF is applied to the determination of the acidity of solutions in etch baths. The response time in the operating range is 10–20 s; the standard deviation is no more than 4%. 相似文献
24.
M. M. Konopleva L. P. Smirnova V. T. Glyzin V. L. Shelyuto 《Chemistry of Natural Compounds》1979,15(3):269-272
A new acylated flavone glycoside has been isolated for the first time from the herb marsh cudweed, and for it the structure of 6-caffeyl-7--D-glucopyranosyloxy-4,5-dihydroxy-3,6dimethoxyflavone has been established. In addition, the aglycone, identified as 4,5,7-trihydroxy-3,6-dimethoxyflavone has been isolated. The identifications were made on the basis of UV, IR, PMR, and mass spectra, the products of alkaline and acid hydrolyses, and the results of elementary analysis, melting points, and specific rotations.Vitebsk Medical Institute. All-Union Scientific-Research Institute of Medicinal Plants, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 311–315, May–June, 1979. 相似文献
25.
V. N. Artem'eva Yu. M. Boyarchuk E. A. Smirnova E. N. Kukarkin V. V. Kudryavtsev M. M. Koton 《Russian Chemical Bulletin》1990,39(3):460-463
H-bond complexes of benzophenonetetracarboxylic acid dimethyl ester with 2,6-diaminopyridine (BZPE·DAP) have a dimeric structure in which one of the amino groups of the diaminopyridine participates in the formation of an H bond and the other does not form strong intermolecular bonds. During thermal imidization, the relative reactivity of the free amino group is lower than the reactivity of the group bound in the complex. In the BZPE·DAP system, 10% of the free amino groups remain after completion of imidization and they disappear at a high temperature. It is hypothesized that they can participate in the formation of interchain imide bonds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 530–533, March, 1990. 相似文献
26.
N. L. Smirnova 《Journal of Structural Chemistry》1995,36(4):691-693
M. V. Lomonosov Moscow State University. Translated fromZhumal Struktumoi Khimii, Vol. 36, No. 4, pp. 760–763, July–August, 1995 相似文献
27.
Lebedev B. V. Kulagina T. G. Smirnova N. N. Shifrina Z. B. Averina M. S. Rusanov A. L. 《Journal of Thermal Analysis and Calorimetry》2003,74(3):735-748
In an adiabatic vacuum calorimeter, the temperature dependence of the heat capacity C
p of phenylated polyphenylene and initial comonomer 1,4-bis(2,4,5-triphenylcyclopentadienone-3-yl)benzene was studied between
6 and 340 K with an uncertainty of about 0.2%. In a calorimeter with a static bomb and an isothermal shield their energies
of combustion DUcomb were measured. From the experimental data, the thermodynamic functions C
p
0 (T), H
0(T)-H
0(0), S
0(T)-S0(0), G
0(T)-H
0(0) were calculated from 0 to 340 K, and standard enthalpies of combustion ΔH
comb
0 and thermodynamic parameters of formation-enthalpies ΔH
f
0, entropies ΔH
f
0, Gibbs functions ΔG
f
0 - of the substances studied were estimated at T=298.15 K at standard pressure. The results were used to calculate the thermodynamic characteristics (ΔH
f
0 ,ΔS
f
0, ΔG
f
0) of phenylated polyphenylene synthesis in the range from 0 to 340 K.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
28.
V. N. Ananin P. A. Vityaz N. P. Glukhova V. E. Romanenkov T. A. Smirnova A. I. Trokhimetz 《Reaction Kinetics and Catalysis Letters》1985,27(2):393-397
The structure of oxide films of aluminium powders has been established to depend on the size of its particles. The temperature dependence of the oxidation of the powder in air is ascribed to changes in both the structure of the oxide laver and the pressure of saturated aluminium vapor. The porous, permeable product consists of hollow microspheres of -Al2O3.
. , . , –Al2O3.相似文献
29.
S. G. Yunusova S. D. Gusakova A. I. Glushenkova U. K. Nadzhimov Sh. Turabekov SA. Musaev 《Chemistry of Natural Compounds》1991,27(2):147-150
A comparative analysis has been made of the amounts of lipids and their fatty-acid compositions in the seeds of the lines of agenetic collection of cotton plants of the speciesGossypium hirsutum and their hybrids and the variety Tashkent-1. The results obtained on the fatty-acid compositions of some hybrids make it possible to recommend the use of individual lines of cotton plants as donors for improving the food-value indices of cottonseed oil.Institute of Chemsitry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. V. I. Lenin Tashkent State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 173–176, March–April, 1991. 相似文献
30.
T. V. Golovko O. B. Smirnova N. P. Solov’eva O. S. Anisimova V. G. Granik 《Russian Chemical Bulletin》2007,56(5):1032-1040
Condensation of lactim ethers of 3,4-dihydrocarbostyril and 1H-2,3,4,5-tetrahydrobenz[b]azepin-2-one with malonodinitrile, cyanoacetamide, and ethyl cyanoacetate gave the corresponding 2-methylidene derivatives.
Their reactions with dimethylformamide diethyl acetal followed by cyclization into benzo[b][1,6]naphthyridines and pyrido[4,3-b]benz[f ]azepines were studied.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 995–1002, May, 2007. 相似文献