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Analytical expressions for the interaction energy of 60° and screw dislocations with Burgers vectors b = a/2 〈110〉 with point defects in f.c.c. crystals (slip system {111} 〈110〉) are obtained in the framework of anisotropic elasticity theory. The point defects (impurities or radiation defects) considered are elastic dipoles of following kinds: 〈100〉 tetragonal, 〈111〉 trigonal, and 〈110〉 orthorhombic. The analytical expressions for the interaction energy in the isotropic approximation as a limiting case of the anisotropic theory are derived and the corresponding force–distance profiles are obtained. In the isotropic approximation the analytical formulae are presented also for the elastic interaction energy of a mixed (111)-glide plane dislocation splitted into two partial Shockley dislocations with [110]- and [101]-point defects. Some erroneous analytical results used in the literature are pointed out and corrected. [Russian Text Ignored].

The interaction of dislocations with impurities in MgCd, MgAg, ZnCd, and ZnAg crystals having different degree of elastic anisotropy is investigated with the help of expressions for the energy and force-distance profiles of the dislocation-tetragonal defect interaction for the basal, prismatic, and pyramidal (both of the first- and the second-order) slip systems. Elastic anisotropy essentially affects the character of the dislocation-impurity atom interaction. In ZnAg anisotropic crystals at gliding edge dislocations of the basal and the first-order pyramidal systems a more complicated interaction character is shown as compared to the dilatational one. Activation energies for overcoming the point defect by an edge dislocation are calculated as functions of the external stress. Pecularities of the dislocation motion are discussed. [Russian Text Ignored].

A short review of the basic approximations used in calculating energy characteristics of elastic interaction of straight dislocations with point defects (elastic dipole) is given. The use of the isotropic medium approximation and a number of special assumptions on the character of the distortions due to the point defect in the crystal lattice is rough and does not reproduce the main features of interaction. With the elastic dipole characteristics known the calculations are possible within the anisotropic theory of elasticity. Nowadays the main procedures of determining the characteristics of elastic dipoles are experimental studies. Some general (basically analytical) results on the investigation of interaction within the anisotropic theory of elasticity for cubic and h.c.p. crystals are discussed. [Russian Text Ignored]

On of the basis of the general treatment made by Teutonico the analytic dependence of the energy factor K of straight dislocations on the angle Φ between the direction of a dislocation and the Burgers vector for the following slip systems in hexagonal crystals are obtained: a) (0001) 〈1210〉; b) {1010} 〈1210〉; c) {1010} 〈0001〉; d) {1011} 〈1210〉; e) {1011} 〈1123〉; f) {2112} 〈2113〉. The stability of straight dislocations in Zn, Be, Zr (at 300 K), and SiO2 (at 873 K) for such slip systems is investigated by means of plotting the polar diagram K−1 (Φ). The possibility of polygonal (zig-zag shape) dislocation formation is shown for Zn and Zr in the slip systems b), d), e), for Be in the slip system b) and for SiO2 in the slip systems b) and d). [Russian Text Ignored]

On the basis of the results from our discussion of the elastic interaction of a selfinterstitial atom with screw and edge dislocations in a bcc iron crystal, we can make the following conclusions.

With the use of the anisotropic theory of elasticity the energies and the force-distance profiles for the interaction of various types of straight dislocations with point defects of intrusion (atoms of N, C or O) and of replacement in BCC metals with a different degree of elastic anisotropy (Nb, V, Ta, α-Fe) have been calculated. The calculated force-distance profiles in most cases are not centrally symmetric, that leads up to a gliding asymmetry at the direct and reverse directions of dislocation motion. The crystal elastic anisotropy can change the relative mobility of dislocations of various types and accounts for a number of experimentally observed peculiarities of BCC metals stress-strain properties. Mittels der anisotropen Elastizitatstheorie wurden die Energien und Kraft-Abstands-Profile fur die Wechselwirkung verschiedener Typen von geraden Verzetzungen mit intrusiven Punktdefekten (N-, C-, O-Atomen) und des Ersatzes in krz-Meallen mit unterschiedlichem Grad der elastischen Anisotropie (Nb, V, Ta, α-Fe) berechnet. Die berechneten Kraft-Abstands-Profile sind in den meisten Fallen nicht zentral-symmetrisch; dies fuhrt zu einer Gleitasymmetrie in der Hin- und Herrichtung der Versetzungsbewegung. Die elastische Kristallanisotropie kann die relative Beweglichkeit der Versetzungen unterschiedlichen Typs andern und ist fur mehrere experimentell beobachtete Besonderheiten der Spannungs-Dehnungseigenschaften der krz-Metalle verantwortlich.

The effect of the oscillation amplitude and temperature on the amplitude-dependent internal friction caused by oscillations of dislocation segments in elastic fields of immobile point defects is investigated. A method is proposed for the determination of the binding energy and force law of the interaction between a defect and dislocation from the relationship between the temperature and oscillation amplitude at the constant level of the internal friction and for the determination of segment-length distribution from the amplitude dependence of the internal friction. [Russian text ignored].

Many container glassware factoriesare being technically reequipped, widely adopting high-productivity technological lines LUS-2 with glass-forming machines VV-7 to manufacture bottles. At specific glass factories (for example, at Merefyanskii, Mineralovodskii) even more productive lines with automation S-10, W-12 have been adopted. The daily productivity of such lines attains 120-130 thousand 0.5-1iter capacity bottles.

A family of DNA sequences (Sau3A repeat sequences) has been revealed in genomes of two forms of O. nerka. A DNA fragment belonging to this "family" has been cloned in bacterial plasmid. Its copy number (in genomes of normal (570 +/- 33) and dwarf (66 +/- 12) forms) has been counted. The structural organization of sequences of Sau3A family in genomes of males and females of normal form is not the same. The organization of Sau3A sequences is the same in genomes of dwarf males and dwarf females of normal form, but the quantity of Sau3A sequences copies is smaller. It is supposed that the DNA sequences of Sau3A family bear the sex determination of dwarf form of O. nerka. The fragment of rRNA gene of nerka has been cloned and the number of rRNA gene copies in genomes of normal (200 +/- 62) and dwarf (1690 +/- 24) forms has been defined.

The study of the activity of nucleolus-forming areas in bone marrow and blood cells in 67 children with acute leukemia has shown the parameter variability depending on histogenetic affiliation, differentiation degree and on the proliferative activity of the cells.

This paper reports a study of the effect of temperature and strain amplitude on Young’s modulus and ultrasonic damping in ceramic samples of graphitelike boron nitride prepared in the RF and USA by different technologies and using various additions to improve the mechanical properties of the ceramic. It is shown that, in addition to the influence on the effective elasticity modulus, additions improve the sample microplasticity, which apparently increases the strength of the material.

The results of studying the level of charge separation between the core and sheath in cables with mineral insulation and nickel and stainless-steel conductors are presented. The cables were irradiated in a BARS-6 pulsed reactor with dose rates of 3 × 103 and 4 × 103 Gy/s at temperatures of 270–650 K. A mechanism for elucidating the complex temperature dependence of the level of temperature-induced charge separation is proposed.

It is experimentally demonstrated that the intensity of the radiation-induced luminescence (RIL) of KU-1 and KI quartz glasses at 450 nm increases more than ten times upon the proton irradiation (proton energy, 8 MeV; dose rate, 5×103 Gy/s; dose, up to 1.2×107 Gy) to a dose of 106 Gy. At a dose exceeding 106 Gy, the spectral efficiency of the ionizing radiation energy conversion reached ∼10−6 nm−1 in the maximum of the RIL band at 450 nm for all types of glasses. After preliminary low-rate γ-irradiation (below 0.5 Gy/s), the RIL intensity in the beginning of the proton irradiation and its variation with the proton dose depend on the concentration of impurities in the quartz glass. The RIL intensity buildup depends on the formation of positively and negatively charged microscopic regions in glasses.

1. As the result of complex alloying of magnico alloy with boron, cerium, and silicon we developed alloy YuNDK23RTsS with a high magnetic energy and better polishability. The alloy is recommended for mass production of permanent magnets. 2. Unlike the original alloy, the new alloy has two zones in which it is homogeneous (high-temperature), which makes it possible to reduce the quenching temperature from 1280 to 1000°C.