A system for real-time measurements of current-density distribution in low-energy electron beams with large cross sections

A system for real-time measurements of the current-density distribution in electron beams ejected from large-area electron accelerators has been developed. The system, which is based on Faraday cups, a microprocessor, and a PC, is designed for measuring the parameters of the electron beams ejected from large-area accelerators—devices for ionizing electroionization lasers and technological accelerators—and ensures real-time monitoring of the current-density distribution over the electron-beam cross section with a relative measurement accuracy of at least ±2%.     

Phase equilibria in the system Al-Rh

Methods of differential thermal analysis, x-ray diffraction, microstructural analysis and electron probe microanalysis are used to study alloys of the Al-Rh system over the whole concentration range. It is established that the phase of equiatomic composition AlRh melts congruently at 2060°C and it has an extended range of homogeneity (45.1–54.2 at.% Rh). The solubility of aluminum in rhodium reaches 9 at.%, decreasing to 6 at.% at 850°C. Coordinates are determined for the eutectic point l ⇆ AlRh + 〈Rh〉 as 70 at.% Rh and 1715°C. The existence of intermediate phases, their crystal structure, and also the method of forming phases in the field of composition rich in aluminum given in publications are confirmed. __________ Translated from Poroshkovaya Metallurgiya, Nos. 5–6(449), pp. 48–56, May–June, 2006.     

Basics of synthesis and application of pseudohomogeneous coal and petroleum feedstock hydrogenation catalysts

The mechanism of formation and properties of emulsion-synthesized globular pseudoheterogeneous catalysts are considered. The results of application of these catalysts to coal hydrogenation and other industrial-chemistry processes are reported.     

Digital forecasting control with the use of neural predictors

The use of prognostic control methods in the digital systems controlling asynchronous electric drives are considered. The methodology for synthesizing predictors on the basis of neural networks is explained. An example of the synthesis of a numeral predictor for a closed control loop is considered.     

Textural states of a hot-worked MA2-1 magnesium alloy

Quantitative texture analysis is used to study texture formation in an MA2-1 magnesium alloy subjected to axisymmetric upsetting at temperatures of 250–450°C and strain rates of 10^?4–10^{0 ?1}. The deformed structure is examined by optical microscopy, and the results obtained are used to plot the structural-state diagram of the alloy after 50% upsetting. The experimental textures are compared with the textures calculated in terms of a thermoactivation model.     

Electrical passivation of the silicon surface by organic monolayers of 1-octadecene

The electrical properties of structures consisting of a monolayer of 1-octadecene deposited on the Si surface are investigated depending on the method of passivation of the surface prior to the deposition of the film (hydrogen and ion passivation) and the intensity of illumination which activates the addition reaction of molecules of 1-octadecene to the Si atoms. The monolayer of 1-octadecene on the Si surface is stable and provides the chemical passivation of the surface. Two types of traps are found, namely, traps for holes and electrons, whose density can be varied during deposition of the monolayer by the choice of intensity of illumination and by the method of passivation of the surface. In the case of a low level of illumination and/or the use of the iodine passivation of the surface, the electron traps prevail, and, in the case of high intensity of illumination and/or hydrogen passivation of the surface, the hole traps prevail. It is shown that the use of these films provides conductivity in thin near-surface layers of Si due to providing the mode of flat bands or accumulation of carriers near the surface.     

Determination of the fracture toughness of inhomogeneous three-layer fusion claddings on compact specimens

We propose a method for the evaluation of the fracture toughness (K _1C ) of multilayer fusion claddings on compact specimens at elevated temperatures (20, 70, and 300°C) with cladding (in the slot) of three layers of materials with gradually increasing crack resistance. As the testing temperature increases, the value of K _1C decreases for harder and stronger fusion claddings and, vise versa, increases for less strong and softer materials. __________ Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 3, pp. 121–122, May–June, 2007.     

Investigation of the Thermal Conductivity of Methanol–n-Hexanol Mutual Solutions at High Parameters of State

The thermal conductivity of methyl and normal hexyl alcohols and of methanol–n-hexanol solutions in wide ranges of temperature and pressure are measured in a facility implementing the regular regime method. The regularity of variation of the thermal conductivity of binary solutions with concentration is found.     

COPART:一种面向约束条件的自适应软硬件划分算法

本文介绍一种将自适应算法、遗传算法和列表调度算法结合起来应用于软硬件划分问题的算法COPARTART，并提出了一种基于约束条件的开销系数自适应调整方法，该方法所获得的划分结果能够良好体现设计目标。