Enhanced Physical and Mechanical Properties of Nitrile-Butadiene Rubber Composites with N-Cetylpyridinium Bromide-Carbon Black

The physical and mechanical properties of nitrile–butadiene rubber (NBR) composites with N-cetylpyridinium bromide-carbon black (CPB-CB) were investigated. Addition of 5 parts per hundred rubber (phr) of CPB-CB into NBR improved the tensile strength by 124%, vulcanization rate by 41%, shore hardness by 15%, and decreased the volumetric wear by 7% compared to those of the base rubber-CB composite.     

Kinematic grouping of reflections of parametric X-ray radiation

A model of parametric X-ray radiation (PXR) of moderately relativistic particles is developed within the kinematic theory taking into account radiation absorption. The model allows calculation of the PXR reflection intensity in a given direction taking into account diffraction of virtual photons on a set of “incidental” low-index crystallographic planes. It is shown that when a charged particle moves along certain crystallographic directions, the effect of kinematic grouping of reflections, at which lines of parametric radiation from various planes practically coincide, is observed.     

Study of Features of the Diffraction of X Rays in a Quartz Crystal Modulated by Longitudinal and Transverse Ultrasonic Vibrations

JETP Letters - Features of the simultaneous action of longitudinal and transverse ultrasonic vibrations in the quartz crystal on the parameters of reflected X-rays are studied. It is shown that...     

Using a plane wave approximation in simulation of radiation distribution in an X-ray Talbot interferometer

This study is devoted to the analysis of the plane-wave approximation applicability to X-ray radiation incident on an object. Based on simple calculations, it is shown that an X-ray tube focal spot 0.4 × 0.8 mm in size at distances of ~1 m can be considered as a point source; however, the plane-wave approximation for such X-ray radiation with energy E = 22keV is valid for radiation source–object distances much longer than 10 m.     

Radiation-Chemical Aspects of Radioactive Waste Management

Studies of radiation-chemical processes in model liquid radioactive waste are summarized. These processes are radiolytic transformations of various substances present in the waste (actinide ions (primarily, neptunium and plutonium ions), inorganic matter (for example, nitrate ions), and organic compounds (acetic acid, EDTA, etc.)) and radiolytic gas evolution. Attention was focused on the latter process. The volumes and compositions of gases formed in the -radiolysis of aqueous solutions that simulated intermediate-level and high-level liquid waste were determined. It was found that the nature and the radiation-chemical yields of released gases depend on the absorbed dose, the composition and concentration of solutions, the irradiation temperature, the presence of solid substances, etc. In a number of cases, data obtained with model solutions were compared to the results of studies of real liquid radioactive waste.     

Study of the kinetics of the oxidation of palladium(II) by inorganic free radicals in acidic aqueous solutions by pulse radiolysis

Conclusion The rate constants for the reactions of OH^., NO₃ ^., and SO_4– ^. with Pd(II) ions in aqueous solutions of the acids have been measured by the pulse radiolysis method. An inner-sphere mechanism of electron transfer.occurs in such reactions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1001–1004, May, 1988.     

Incorporation of sodium into silicon dioxide film fabricated in glow discharge plasma

Results of experiments on the plasma-assisted fabrication of a silicon dioxide film with incorporated sodium are reported. The film was obtained via the decomposition of vaporized tetraethoxysilane and sodium compounds in a glow-discharge plasma and the deposition of the degradation products on a substrate. It is shown that this procedure makes it possible to incorporate up to 7 wt % sodium in the film composition.