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31.
We examine a control linear system of ordinary differential equations with an identically degenerate matrix coefficient of the derivative of the unknown vector function. We study the question of the minimal dimension of the control vector when the system could be fully controllable on any segment in the domain of definition. The problem is investigated in the cases of stationary systems and the systems with real analytic and smooth coefficients for which some structural forms can be defined.  相似文献   
32.
The formation of heterometallic oxovanadium(iv) diethylenetriaminepentaacetates with titanium(iii), chromium(iii), cobalt(ii), nickel(ii), and manganese(ii) cations in aqueous solutions was studied by spectrophotometry and pH-metry. The stabilizing influence of heterometallic chelation on an unstable oxidation state of Ti iii and the labilizing effect of oxovanadium(iv) cations on the coordination of Cr iii cations by the carboxylate ligand anions in the heterometallic complex were shown. The optimum conditions for the formation of the heterometallic dtpa complexes were selected and their thermodynamic stability was estimated. The states of the oxovanadium(iv) cations in the monoand heteroligand systems involving polyamine, polyaminopolycarboxylate, and alkylpolyphosphonate ligands were studied. Specific features of ligand coordination and formation of the mixed-ligand chelates were investigated. A variety of molecular compositions of complex oxovanadium(iv) oxyethylenediphosphonate particles formed in ranges of pH 2.2—3.0, 4.5—5.5, and 6.3—6.4 was found. The preferability of formation of polynuclear oxovanadium(iv) oxyethylidenediphosphonates, viz., binuclear particles with oxovanadium(iv) cation to ligand molar ratios of 2 : 1 and 2 : 5 and trinuclear particles with a molar ratio of components of 3 : 2, was shown.  相似文献   
33.
It is proved that the least energy solution of the BVP
, is a constant for all q ∈ (2; 2*] if Q ⊂ ℝn (n ≥ 3) is a sufficiently thin cylinder. Bibliography: 8 titles. __________ Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 348, 2007, pp. 272–302.  相似文献   
34.
Under study are the systems of quasilinear time-delay differential equations with parameters and periodic coefficients. Some sufficient conditions are derived for asymptotic stability of the zero solution, and the estimates of solutions are obtained that characterize the decay rate at the infinity.  相似文献   
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36.
We consider a system of nonlinear ordinary differential equations that are unsolved for the derivative of the unknown vector function and identically degenerate on the domain. We prove a theorem on the unbounded extendability of solutions to this system, allowing arbitrarily high unsolvability index with respect to the derivative.  相似文献   
37.
We obtain 16 center conditions for a polynomial differential system with 27 parameters.  相似文献   
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39.
Two methods of covalent grafting of a protein onto a calcite surface were developed. Single-molecule force spectroscopy was used to examine the characteristics of individual albumin-albumin polyclonal body complexes. The practical applicability of the proposed method of covalent grafting of a protein to a calcite surface was demonstrated.  相似文献   
40.
The ion-chromatographic behavior of anionic transition metal complexes of 1,2-cyclohexanediaminetetraacetic acid (CHDTA) on polymeric anion exchangers was studied. It was demonstrated that two-column ion chromatography can be used for studying the complexation of CHDTA with transition metal ions in alkaline solutions. A method was proposed for the calculation of equilibrium constants of complexation reactions and stability constants from the data of ion-chromatographic measurements.  相似文献   
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