Estimation of the Viscosity Properties of Solutions of Aromatic Copolyamides

The viscosity properties of dilute solutions of two modifications of Armalon (MD and X) with properties of other rigid-chain aromatic copolyamides are compared. The best affinity of 96% sulfuric acid for PPTA and Armalon-MD and the worst affinity for Armalon-X are demonstrated.__________Translated from Khimicheskie Volokna, No. 1, pp. 24–26, January–February, 2005.     

The covolume and equation of state of high-temperature real gases

It is shown that the equation of state of a real gas can be described under certain conditions in terms of the covolume.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 51, No. 2, pp. 273–275, August, 1986.     

Determination of the parameters of circuit models of resistive microwave structures

New methods of determining the parameters of circuit models of resistive microwave structures are considered, based on a measurement of the wave scattering parameters of the contact device, consisting of coaxial-stripline transitions, a stripline transmission line and the structure analyzed. Results which demonstrate the high efficiency of the proposed methods of solving the problem are presented. __________ Translated from Izmeritel'naya Tekhnika, No. 8, pp. 51–55, August, 2008.     

Reliability and Completeness of Data on the Impurity Composition of High-Purity Volatile Compounds

A procedure is proposed for assessing the completeness and reliability of data on the impurity composition of high-purity volatile substances. The procedure is illustrated with application to the samples of volatile substances (hydrides, chlorides, permanent gases, and metalorganic compounds) present at the permanent exhibition–collection of extrapure substances (ECES), Russian Academy of Sciences.     

Frequency conversion of optical signals in p-i-n photodiodes

A planar InGaAsP/InGaAs/InGaAsP p-i-n photodiode has been fabricated and used for frequency conversion of two optical signals. Nonlinear properties of the photodiode have been investigated. It is shown that photodiode responsivity R(V) dependence on bias voltage can be characterized by a parameter of the nonlinearity A, which is equal to R(V)middotR'(V) and the maximal conversion efficiency is achieved at the bias voltage where the parameter A has the maximal value     

Properties of electrolytic dispersed powders of tungsten and molybdenum carbides

We investigated the physicomechanical and service properties of electrolytic dispersed powders of tungsten and molybdenum carbides produced by high-temperature electrochemical synthesis. We show the possibility of using them as a hard ceramic alloy and catalyst in reactions of electrorelease and electrodissolution of hydrogen. Vernadskii Institute of General and Inorganic Chemistry, Ukrainian Academy of Sciences, Kiev. Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 36, No. 1, pp. 93–98, January–February, 2000.     

Synthesis of an information channel in planning goal functioning of space remote sensing systems according to quality criteria

Quality criteria for an image received from optic-electronic complexes of space remote sensing systems and methods of evaluating these quality criteria that allow one to choose parameters of elements of a ground space information channel together with orbital design of space remote sensing systems are considered.