Formation of alumina-silver-palladium systems

Diffuse-reflection electron spectroscopy was used to investigate the state of alumina-silver-palladium catalysts as a function of the conditions of synthesis and heat treatment. Mono- and bimetallic particles were found to be present on the surface of a catalyst manufactured by impregnation of the carrier from one impregnating solution. Premodification of the carrier with palladium is accompanied by formation of metal implantation structures in the carrier lattice, while silver modification does not produce such structures. In the Pd/Ag/Al₂O₃ catalyst, palladium occurs at several oxidation levels. Institute of Physico-Organic Chemistry, Academy of Sciences of Belarus, 13, Surganov St., Misnk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 2, pp. 169–172, March–April, 1997.     

Magnetic phase transitions in TbNi<Subscript>5</Subscript> single crystal: Bulk properties and neutron diffraction studies

The angular dependence of the intensity of CK_α radiation measured from a film of oriented carbon nanotubes shows an increase in the yield of x-ray fluorescence along the growth direction of the nanotubes. The angular distribution of the intensity of scattered x rays is close in magnitude to the angular distribution of the directivity of nanotubes in the film that is determined by analyzing an electron-microscope image. To explain the propagation of radiation along the nanotubes, two mechanisms are proposed on the basis of reflection from inner walls of a tube (channeling) and an anomalous dispersion of CK_α photons in the carbon medium.     

Spectroscopic monitoring of boprylation of cotton fiber from wilt-infected plants

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 5, pp. 812–815, November, 1990     

A New Approach to the Estimation of a Stationary State in Flow-Injection Analysis

An approach to calculating the rate of entropy production in a system was developed to characterize the stationary state in flow-injection systems on the basis of principles of nonequilibrium thermodynamics, and its relationship to the parameters of the measured peak was found. Thus, it became possible to make quantitative relative estimations in real systems. By the example of a classical flow-injection spectrophotometric determination of uranium with Arsenazo III, it was shown that the rate of entropy production can be estimated from experimental data. It was found that the peak-averaged rate of entropy production decreases with concentration. It was found that, at the moment of the measurement of the peak maximum, this value is actually minimum and nonzero, and the nonlinear dependence corresponds to the best calibration function because of the effect of nonequilibrium factors.     

Diffusion of Tl-204 isotope and ionic conductivity in Tl4HgI6 membrane material for chemical sensors

Method for solid-phase synthesis of Tl₄HgI₆ was developed and the diffusion coefficients of thallium-204 isotope were determined for this compound for the first time. Data on the ionic conductivity and diffusion of thallium ions were obtained and used to calculate the defect concentration and mobility in the thallium sublattice.     

The interactive system “PARACHUTE”

The structure and uses of an interactive system are described. The results of computations of the resistance and inflatibility of corrugated parachute canopies are presented.Translated fromDinamicheskie Sistemy, No. 6, 1987, pp. 30–35.