Energy of local uniaxial distortions in the crystal lattices of 5d metals

A simple model is proposed for estimation of the internal-energy change that takes place in paramagnetic transition metals in real and virtual high-symmetry crystalline modifications under uniaxial distortions of the lattice. This change is analyzed as a function of electron concentration against the background of energy competition between the phases considered. V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 50–53, June, 1998.     

Synthesis of n-methyl-3-carboxy-2-chloro-dibenzo[<Emphasis Type="Italic">c,f</Emphasis>][1,4,5]oxa-thiazepine s,s-dioxide and its derivatives

A new dibenzo-condensed oxathiazepinecarboxylic acid was obtained starting from the methyl ester of 2,4-dichloro-5-chlorosulfonylbenzoic acid. Derivatives were obtained from N-phenylamide and N-methylamide of 2,4-dichloro-5-chlorosulfonylbenzoic acid. Methods for the preparation of the starting aromatic sulfonyl chlorides were proposed.     

Influence of Postgrowth Processing Technology on the Laser Induced Damage Threshold of ZnGeP2 Single Crystal

Russian Physics Journal - The laser induced damage thresholds of ZnGeP2 single crystals are determined. The values of the thresholds under the action of laser radiation at a wavelength of 2,097...     

Preparation of composite materials on the basis of polyvinyl chloride and nanomodifiers

The influence of carbon nanocompositions on physical-mechanical properties of polyvinyl chloride was investigated.     

Statistical fracture modeling of weld joint for nuclear reactor components

Probabilistic safety and risk assessment of nuclear reactor equipment are referred to as integrated safety assessment which is implemented by the application of probabilistic fracture mechanics (PFM). Such a study is based on statistical simulation of weld damages under dynamic condition. Because of damage accumulation in welded nuclear reactor components under dynamic load, the need for evaluating the risk of fracture is apparent. This work considers the statistical simulation of dynamic damage of weld joint by fracture. Considered in the analysis are weld defects, damage accumulation, crack initiation and crack growth.     

Intensification of Preparation of Modified Polycaproamide Fiber

A procedure was developed for graft polymerization of dimethylaminoethyl methacrylate onto polycaproamide using a redox system whose components are added to the reaction mixture sequentially. A scheme of radical graft polymerization of dimethylaminoethyl methacrylate onto polycaproamide was suggested. The properties of the copolymers were studied. The materials based on modified polycaproamide show promise as chemisorbents.     

Synthesis of Novel Five-membered Nitrogen-containing Heterocyclic Compounds from Derivatives of Arylsulfonyl- and Arylthioacetic and -Propionic Acids

A series of novel substituted 1,3,4-oxa(thia)diazoles and triazoline-3-thiones has been synthesized from thiosemicarbazides and nitriles of arylthio-, arylsulfonylacetic and -propionic acids. A mechanism is proposed for the preparation of 2-amino-5-substituted 1,3,4-thiadiazoles from carboxylic acids in polyphosphoric acid medium.     

Influence of resonators on the acoustic and propulsion performance characteristics of a ramjet ejector chamber under conditions with vibration hydrogen combustion

The influence of acoustic resonators on the acoustic and propulsion performance characteristics of a ramjet ejector chamber under conditions with vibration hydrogen combustion was experimentally examined. In the study, resonators having identical throats and different cavity diameters were used. For fixed-volume resonators the best propulsion performance characteristics were achieved in the case in which the cavity diameter differed little from the resonator throat diameter.     

Zinc Oxidation in Limited Volume of Alkaline Electrolyte

Russian Journal of Electrochemistry - Studies of zinc electrode oxidation under the conditions of limited volume of alkaline electrolyte are carried out. It is shown, that at anodic polarization...     

SOLVING THE PROBLEMS OF MECHANICS OF CYLINDRICAL ANISOGRID LATTICE BODIES OF SPACECRAFTS

Journal of Applied Mechanics and Technical Physics - Results of solutions to problems of determining the parameters of anisogrid lattice structures of spacecraft bodies are presented. These...