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901.
S. A. Mikhalenko L. I. Solov’eva E. A. Luk’‘yanets 《Russian Journal of General Chemistry》2004,74(11):1775-1800
Procedures have been developed for the synthesis of a series of metal complexes derived from water-soluble anionic and cationic octa-4,5-carboxyphthalocyanine-taurine and choline conjugates.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1907–1911.Original Russian Text Copyright © 2004 by Mikhalenko, Soloveva, Lukyanets.For communication XXXVII, see [1].This revised version was published online in April 2005 with a corrected cover date. 相似文献
902.
N. I. Yanchuk 《Russian Journal of General Chemistry》2006,76(8):1240-1242
The α-effect in the reactions of O,O-diaryl phosphorohydrazidothioates with phenyl isothiocyanate in benzene at 25°C was quantitatively evaluated from the kinetic data. The probable reaction mechanism was suggested, and the causes of the α-effect in these reactions are discussed. An approximate linear correlation is observed between the α-effect in the reactions of O,O-diaryl phosphorohydrazidothioates with phenyl isothiocyanate, basicity constants of the hydrazides, and σp constants of the substituents at the P atom. The value of the α-effect is largely determined by the structure of the transition state. 相似文献
903.
G. I. Golodets 《Theoretical and Experimental Chemistry》1985,21(5):525-529
An antibatic relation has been established between the catalytic activities r of metals in relation to hydrogenation of CO and the selectivity in relation to methane
. A mechanism is proposed for the reaction which makes it possible to interpret the observed kinetic relationships, the sequences of activities and selectivities, and also the relation between r and
.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 5, pp. 549–553, September–October, 1985. 相似文献
904.
J. N. Kotzev M. I. Aroyo M. N. Angelova 《International journal of quantum chemistry》1985,27(1):45-58
The relations between isoscalar factors for corepresentations of antiunitary magnetic point groups are discussed in the case of associated corepresentations. The tables of the isoscalar factors for the single- and double-valued corepresentations of all tetragonal, orthorhombic, monoclinic, and triclinic Shubnikov point groups are given. Some peculiarities of the calculation method of the isoscalar factors for corepresentations are considered. 相似文献
905.
E. S. Klimov F. Kim V. Kh. Sabanov T. I. Chulkova O. Yu. Okhlobystin 《Theoretical and Experimental Chemistry》1992,28(1):58-60
1,8-Naphthylenediamine was reacted with 2,6-di-tert-butyl-4-formyl-phenol to produce 2,6-di-tert-butyl-4-(1,3-dihydro-perimidyl) phenol (I). The latter was coverted into 2,6-di-tert-butyl-4-(1H-perimidyl)phenol (II) by oxidizing I with sodium pyrosulfate. When phenol II was oxidized by lead dioxide in toluene and THF, the EPR spectra revealed a 12-component multiplet with perimidyl splitting constants a1
N=a3
N=aH
NH=0.2 mT; aH
6.7=0.6 mT.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 28, No. 1, pp. 64–67, January, 1992. 相似文献
906.
A. S. Tatikolov Kh. S. Dzhulibekov Zh. A. Krasnaya E. V. Grechkina V. I. Avdeeva V. A. Kuz'min 《Russian Chemical Bulletin》1992,41(11):1985-1991
The absorption spectra of a number of cationic-anionic polymethine dyes in polar, low-polarity, and nonpolar solvents were studied. It was established that in polar solvents the absorption spectra represent the sum of the absorption spectra of the cation and anion, whereas in nonpolar and low-polarity solvents, in many cases the appearance of a short-wave absorption band is observed, due to interaction of the chromophores of the cation and anion in ion pairs. In solvents of intermediate polarity (for example, in chloroform and ethyl acetate), a concentration dependence of the absorption spectra is observed, determined by the equilibria of ionic dissociation. The ionic dissociation constants of a number of cationic-anionic dyes in chloroform and ethyl acetate were determined by a conductometric method. The thermodynamic data obtained are compared with the spectral data.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2524–2532, November, 1992. 相似文献
907.
I. Belič T. Kastelic-Suhadolc R. Kavčič J. Marsel V. Kramer B. Kralj 《Tetrahedron》1976,32(24):3045-3049
The oxidation of higher aliphatic ethers with oxygen at 50° yields two peroxides as the main oxidation products for each ether, namely a dihydroperoxy-dialkyl ether and a dihydroperoxy-dialkyl peroxide. The mass spectra of these compounds are recorded and the main fragmentation pattern is discussed. 相似文献
908.
909.
I. V. Shkutina O. F. Stoyanova V. F. Selemenev 《Russian Journal of Applied Chemistry》2005,78(6):981-984
Some fundamental aspects of the immobilization of a hydrolytic enzyme glucoamylase via adsorption on aminocarboxylic ion-exchangers with fibrous structure were considered. The sorption capacity of amphoteric supports for the enzyme was studied in relation to the time of immobilization, concentration of hydrogen ions and the protein, and the ionic form of a polyelectrolyte. The catalytic properties of free and immobilized enzymes were compared.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 6, 2005, pp. 1003–1005.Original Russian Text Copyright © 2005 by Shkutina, Stoyanova, Selemenev. 相似文献
910.
The National Institute of Standards and Technology (NIST, formerly the National Bureau of Standards or NBS) has produced
numerous Standard Reference Materials (SRM) for use in biological and environmental analytical chemistry. The value listed
on the “NIST Certificate of Analysis” is the present best estimate of the “true” concentration of that element and is not
expected to deviate from that concentration by more than the stated uncertainty. However, NIST does not certify the elemental
concentration of every constituent and the number of elements reported in the NIST programs tends to be limited.
Numerous analysts have published concentration data on these reference materials. Major journals in analytical chemistry,
books, proceedings and “technical reports” have been surveyed to collect these available literature values. A standard statistical
approach has been employed to evaluate the compiled data. Our methodology has been developed in a series of previous papers.
Some subjective criteria are first used to reject aberrant data. Following these eliminations, an initial arithmetic mean
and standard deviation (S.D.) are computed from remaining data for each element. All data now outside two S.D. from the initial
mean are dropped and a second mean and S.D. recalculated. These final means and associated S.D. are reported as “consensus
values” in our tables.
Received: 25 April 1997 / Revised: 24 July 1977 / Accepted: 25 July 1997 相似文献