The thermodynamic properties of calcium uranoborate

The standard enthalpy of formation of crystalline Ca(BUO₅)₂ at 298.15 K was determined by reaction calorimetry (?4491.0 ± 3.5 kJ/mol). The heat capacity of the substance was measured over the temperature range 7–304 K by adiabatic vacuum calorimetry, and its thermodynamic functions were calculated. The standard entropy and the Gibbs function of formation at 298.15 K were found to be ?887.1 ± 2.1 J/(mol K) and-4226.5 ± 4.0 kJ/mol, respectively. The standard thermodynamic functions of calcium uranoborate synthesis reactions were calculated and analyzed.     

The thermodynamic properties of magnesium uranoborate tetrahydrate

The standard enthalpy of formation of crystalline Mg(BUO₅)₂ · 4H₂O at 298.15 K (?5563 ± 10 kJ/mol) was determined by reaction calorimetry. The heat capacity of the compound was studied over the temperature range 8–340 K by adiabatic vacuum calorimetry, and its thermodynamic functions were calculated. The standard entropy and Gibbs function of formation at 298.15 K (?1692.2 ± 3.4 J/(mol K) and ?5059 ± 11 kJ/mol, respectively) were determined.     

Univalent metal uranyl carbonates

Optimal procedures were developed for the synthesis of A _4?m ^I B _m ^I [UO₂(CO₃)₃]·nH₂O (A^I = Li, Na, K, Rb, Cs, NH₄, Ag, Tl; B^I = Na; m = 0?1; n = 0?6) compounds. The structure and thermal decomposition of these compounds were studied by X-ray diffraction, precision IR spectroscopy, and thermal analysis. The IR bands were assigned using mathematical simulation based on small-vibration theory. The standard enthalpies of formation of the compounds at 298.15 K were determined for the first time by reaction calorimetry.     

Adhesives and compounds in manufacture of electronic mechanisms

The general properties of adhesives and compounds for electronic articles are described that were elaborated by the company: TK-1 adhesive with elevated thermal conductivity; TEK-type adhesives that demonstrate higher elasticity and adhesion ability; TK-8-type all-purpose adhesives; MS-type, single-packed, thermally stable glues for long storage; electrically conductive adhesives; TPK-1 and TPK-2 magnetic adhesives and TPK-3 nonmagnetic adhesive; and some compounds, e.g., epoxide molding compositions. The functionality of all adhesives and compounds presented were tested for weather factors, including elevated humidity, higher and lower temperatures, thermal cycles, effects of vibrations for both pilot samples, and final articles of electronic mechanisms.     

Facile synthesis of digermylene oxide and its reactivity towards vanadocene: the first example of Cp2V–germylene coordination

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Boundary Value Problem for a Third-Order Differential Equation with a Strong Boundary Layer

Moscow University Computational Mathematics and Cybernetics - A case is considered in which when the solution to the boundary value problem for a third-order singularly perturbed ordinary...