Calibration relations for <Emphasis Type="Italic">B</Emphasis><Subscript><Emphasis Type="Italic">φ</Emphasis></Subscript>-splines of fourth order

We study necessary and sufficient conditions for the smoothness of (not necessarily polynomial) splines of fourth order. We establish the uniqueness of a space of splines of maximal smoothness and prove embeddings on refined grids. We also obtain the corresponding calibration relations. Bibliography: 12 titles.     

Variational problem of the mechanics of soil-vehicle interaction

Based on a classical approach for the determination of the integral characteristics of soil-vehicle interaction a problem of investigating the influence of geometry of the soil-tracked vehicle interface surface on drawbar pull is posed. The vehicle-soil interaction model of the process of local shear failure is considered. The problem is reduced to an isoperimetric task of the calculus of variations, a Lagrangian is constructed, and the functions involved in the Lagrangian are assessed. The profile of the track contact area providing a drawbar pull extremum under certain assumptions of forming tangential stresses in the contact area is produced.     

Manganese minerals from the Miassovo freshwater lake: Composition and structure

The mineral, chemical, and trace element composition and the microstructures of manganese minerals in bottom nodules and crusts collected from the Bolshoe Miassovo freshwater lake (South Urals) were studied. Freshwater manganese species were shown to have more diversified mineral compositions than in marine species. In addition to (9.6- and 7.2 Å) layered manganese mineral structures, various manganese-containing carbonates were frequently present in lacustrine samples. As opposed to marine samples, lacustrine samples were poor in trace elements, in particular rare-earth elements, but have higher contents of Sr, As, Ti, and V. A structural analysis of lacustrine manganese species showed their biomorphic nature, which manifested itself as organic bacterial species ranging from spherulitic to filamentary ones.     

Standard enthalpies of formation of 4-methylbiphenyl and 4,4′-dimethylbiphenyl

The energies of combustion of 4-methylbiphenyl and 4,4′-dimethylbiphenyl in the crystal state were measured in a precision calorimeter equipped with a self-sealing bomb at 298.15 K. The enthalpies of vaporization of these substances were measured in an isothermal heat-conducting Calvet microcalorimeter. Standard enthalpies of formation were calculated for 4-methylbiphenyl and 4,4′-dimethylbiphenyl in the crystal, liquid, and gas states.     

Kinetic stability of Tm(III) and Sm(III) octaphenyltetraazaporphyrin complexes in acetic acid-based solvents

The state of (octaphenyltetraazaporphyrinato)(acetylacetonato)thulium(III) and (octaphenyltetraazaporphyrinato)(acetylacetonato)samarium(III) in AcOH and in systems AcOH-benzene and AcOH-H₂SO₄ was studied. The stability constant of the acid form of the thulium complex was estimated. The solvoprotolytic dissociation of the complexes in the AcOH-H₂SO₄ and AcOH-benzene systems was studied.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 1937–1941.Original Russian Text Copyright © 2004 by Khelevina, Miroshnichenko, Kabesheva, Kulinich, Shaposhnikov.This revised version was published online in April 2005 with a corrected cover date.     

Research on orotron oscillator with dispersive open resonant system

Theoretical and experimental results of an investigation into a new resonant system have been obtained. This system is named the sphere-corner-echelette open resonator (SCEOR) due to the employment of a mirror that was formed by two echelettes at the angles of 45° to the resonator axis. It turns ont that this resonator is excited on the specific modes not unique to others oscillating systems. There are presented the results of the experimental research of the orotron oscillator with the SCEOR. The spectrum of this device contains only the fundamental modes such as theT E M ₀₀₆,T E M ₀₀₇,T E M ₀₀₈. The efficiency of the orotron is improved, when all other factors are the same the orotron with a much used sphere-cylindrical open resonator.     

Effect of electrolytically deposited nickel films on the magnetic properties of iron-silicon alloy

The effect of electrolytically deposited nickel films on the magnetostriction, coercive force, residual induction, and the position with respect to each other of the magnetic susceptibility maxima _max. _max of specimens of iron-silicon alloy is investigated. It is shown that elastic extensions lead to a reduction in the spacing between the maxima _max, _max , and for certain loads this spacing disappears and only one maximum is observed.     

Investigation of benzimidazole derivatives

The hydrochlorides of the corresponding 2-benzimidazolylmethylhydroxamoyl chlorides were synthesized by the chlorination of 1-methyl-2-formylbenzimidazole oxime and its 5-methyl and 5-nitro derivatives, and 2-benzimidazolylmethylnitrolic acids were obtained by nitration of the oximes. The products of these transformations react with acetylacetone and benzoylacetone in the presence of bases to give 1,5-substituted 3-[2-benzimidazolyl]-4-acyl-5-methylisoxazoles.See [1] for communication XXVII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 812–815, June, 1972.     

Output characteristics of a diffraction radiation generator in the autonomous and nonautonomous modes

Kharkov State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 34, No. 3, pp. 301–308, March, 1991.