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991.
H. D. Sommer und F. Umland 《Fresenius' Journal of Analytical Chemistry》1977,285(5):359-361
Zusammenfassung Alizarin S und seine 11-Metallchelate lassen sich an der Quecksilbertropfelektrode reduzieren. Aus der Beeinflussung der diffusionskontrollierten und der Adsorptionsstufe durch die Chelatbildung lassen sich Aussagen über die Konstitution und Ladung der adsorbierten Chelate machen: Beryllium wird in peri-, Aluminium und Gallium werden in ortho-Stellung des Alizarinmoleküls gebunden. Die 11-Chelate des Be und Al sind ungeladen. Das Ga-Chelat ist negativ geladen und enthält offensichtlich zusätzliche anionische Liganden.Wir danken der Deutschen Forschungsgemeinschaft, Bonn-Bad Godesberg, dem Minister für Wissenschaft und Forschung des Landes Nordrhein-Westfalen, Landesamt für Forschung, sowie dem Verband der Chemischen Industrie, Fonds der Chemie, für Sachbeihilfen. 相似文献
992.
The crystals of Ni0,33Mo3Se4, are triclinic, space group , with two formula units in a cell: a = 6,727 (9) Å, b = 6,582 (11) Å, c = 6,751 (6) Å, α = 90.61° (10), β = 92.17° (10), γ = 90.98° (12.) The structure was solved by analogy with Mo3Se4 and refined by a full-matrix least squares program to R = 0,093 for 822 independent reflexions. The channels present in Mo3Se4 are occupied by Ni so that Ni0,33Mo3Se4 is always a metallic compound. 相似文献
993.
The adhesive secreted by the barnacle, Balanus eburneus, has been demonstrated to contain two hexosamines, glucosamine and galactosamine. Degradation of the hexosamines during hydrolysis of the adhesive appears to be the reason why previous studies of the adhesive have indicated the absence of hexosamines, or the presence of only one hexosamine. 相似文献
994.
D. Klockow 《Fresenius' Journal of Analytical Chemistry》1963,198(3):285
Ohne Zusammenfassung 相似文献
995.
Direct semi-automatic and automatic derivative potentiometric EDTA procedures for the determination of calcium and/or magnesium with a calcium-selective electrode are described. Calcium is titrated in the presence of magnesium at pH 12.0 and the total calcium and magnesium is determined at pH 9.7. Calcium in the range 1-8 mg and magnesium in the range 0.7-5 mg are determined semi-automatically with average errors of about 0.2 and 0.3% respectively and automatically with average errors of 0.4 and 0.7%. Titration times vary from a few seconds to a few minutes. 相似文献
996.
D. I. Zhukhovitskii 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(9):1489-1497
The potential of the interaction of an alkali metal with a planar metal surface was calculated by solving a two-dimensional Schrödinger equation. The potential energy of the valence electron of the atom was derived from a model pseudopotential based on the image potential. It was demonstrated that the potential energy curve for the interaction of an alkali metal atom with the surface of a heavier alkali metal has a minimum at a certain distance from the surface, a feature that gives rise to equilibrium states of levitating atoms. 相似文献
997.
A. L. Podkorytov S. R. Kudakaeva E. V. Sokolova S. A. Shtin D. N. Ashikhmin 《Russian Journal of Inorganic Chemistry》2006,51(1):46-50
The main features of the synthesis of (Pb1-x
Srx)2Nb2O7 and (Pb1-x
Bax)2Nb2O7 pyrochlore solid solutions were determined using isothermal thermogravimetry in tandem with formal-kinetic analysis. The
stability and electron-transport properties of the triple niobates were studied, which allowed us to test them as electrode-active
materials for membranes in ion-selective electrodes (ISEs). 相似文献
998.
V. F. Burdukovskii D. M. Mognonov S. O. Botoeva Zh. P. Mazurevskaya 《Polymer Science Series B》2006,48(2):92-95
It is shown that polyimidates obtained by polycondensation of bisphenols with imidoyl chlorides may be transformed into N-phenylsubstituted aromatic polyamides. The rearrangement occurs as a result of heating at 260–340°C, and, in a diphenyl ether solution, at 240°C. The resulting polymers are soluble in organic solvents and demonstrate high thermooxidative stability. 相似文献
999.
V. M. Yakovlev D. V. Ovchinnikov I. G. Fokeeva 《Russian Journal of Applied Chemistry》2005,78(2):336-338
The dissociation energy of heteronuclear diatomic molecules with polar covalent bonds was calculated by the modified Pauling procedure taking into account the presence of an unpaired electron on one of the atoms.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005, pp. 341–343.Original Russian Text Copyright © 2005 by Yakovlev, Ovchinnikov, Fokeeva. 相似文献
1000.
A linear model is discussed to describe the phosphorus pentoxide content in the product of phosphate beneficiated by calcination, as a function of the impurities in the product. Relationships were found between the concentrations of the impurity variables in the raw material and in the product. These relationships were used to amend the model permitting prediction of the phosphorus pentoxide content in the product as a function of the composition of the raw material. 相似文献