On one mechanism of light ablation of nanostructures

The mechanism of mechanical ablation of nanoparticles during the interaction with a high-power laser radiation pulse is proposed. A particle is polarized under a laser electric field, and electric forces acting on field-induced oppositesign charges cause rupture stresses. Upon reaching the stresses exceeding the maximum allowable values for a given material, a nanoparticle decays into two ones. This effect can be used for narrowing the size distribution of nanoparticles produced by the laser ablation method

Titanium compounds as catalysts of higher alpha-olefin-based super-high-molecular polymers synthesis

The synthesis of polymers of 10 million or more molecular weight is a difficult task even in a chemical lab. Higher α-olefin-based polymer agents of such kind have found a narrow but quite important niche, the reduction of drag in the turbulent flow of hydrocarbon fluids such as oil and oil-products. In its turn, searching for a catalytic system capable to produce molecules of such a high length and to synthesize polymers of a low molecular-mass distribution is part of a global task of obtaining a high-quality product. In this paper we had observed a number of industrial catalysts with respect to their suitability for higher poly-α- olefins synthesis. A number samples representing copolymers of 1-hexene with 1-decene obtained on a previous generation catalyst, a microsphere titanium chloride catalytic agent had been compared to samples synthesized using a titanium-magnesium catalyst both in solution and in a polymer medium

Changes of the body functions during long-term hypokinesia

Prolonged hypokinesis (100-170 days) studied in 2000 rats kept in cages limiting their mobility provoked considerable changes in the gaseous and energetic metabolism: an elevation of the total gaseous metabolism and of the rate of O2 requirement by the muscles (in the late periods of hypokinesis) and a change in the intensity of tissue respiration of the liver and myocardium. There also proved to be a reduction in the level of phosphorylation and separation of oxidative phosphorylation in the myocardium, liver, and partially in the skeletal muscle. Prolonged hypokinesia led to changes in tissue metabolism: a disturbance of development of the animals, a marked delay and an increase in the weight of the organism and the muscular system, and disturbances of the mineral and protein metabolism. Prolonged hypokinesis also lead to exhaustion of the hypothalamus-hypophysis-adrenal cortex system

Application of the Gadolinium Isotopes Nuclei Neutron-Induced Excitation Process

The possibility of transformation of energy of fast and epithermal neutrons to energy of coherent photon radiation at the expense of a neutron pumping of the active medium formed by nucleus with long-living isomerous states is theoretically described. The channel of the nucleus formation in isomeric state as a daughter nucleus resulting from the nuclear reaction of neutron capture by a lighter nucleus is taken into consideration for the first time. The analysis of cross sections’ dependence of radiative neutron capture by the nuclei of gadolinium isotopes Gd155 and Gd156 is performed. As a result, it is stated that the speed of Gd156 nuclei formation exceeds the speed of their “burnup” in the neutron flux. It is provided by a unique combination of absorbing properties of two isotopes of gadolinium Gd155 and Gd156 in both thermal and resonance regions of neutron energy. Conditions required for making isotope nuclei excited by forward neutron scattering on nuclei and for storing nuclei in excited states are formulated. The possibility of excess energy accumulation in the participating medium created by the nuclei of the pair of gadolinium isotopes Gd155 and Gd156 due to formation and storage of nuclei in isomeric state at radiative neutron capture by the nuclei of the stable isotope with a smaller mass is shown. It is concluded that when the active medium created by gadolinium nuclei is pumped by neutrons with the flux density of the order of 1013 cm−2 s−1, the condition of levels population inversion can be achieved in a few tens of seconds. The wave length of the radiation generated by the medium is 0.0006 nm

The Use of Analytical Tools in the Conduct of Internal Control Procedures

The work is devoted to the study of the problems of management, the activities of international companies in solving urgent problems of risk assessment, international cooperation of companies in the development and use of software and the applications of the Business Intelligence class, Data Quality and Business Analytics, the role of SAS in the domestic market. The first part is devoted to the activities of international companies in the field of risk assessment. The second part is devoted to the review of analytical products of SAS.   Keywords: audit, risk assessment, in-depth analytics, business intelligenc

The concept of "Tea" in the language picture of the world (based on Chinese and Russian languages)

This article presents a study of the “tea” concept and its representation in the language picture of the world based on the Russian and Chinese languages and identification of linguistic-cognitive and linguistic-cultural specification of its comprehension by Russian and Chinese people. The following issues were examined in the article: the cultural and historical background of the formation of the “tea” concept, the frequency of occurrence of the “tea” token and also the representation of the “tea” concept in both linguistic worlds. The results were as follows: the language representation of the “tea” concept was described and compared, and the similarities and differences in the content of the concept were revealed. The language representation of the “tea” concept in the Chinese and Russian languages was taken as the material of the study

Spectral properties of a short-range impurity in a quantum dot

The spectral properties of the quantum mechanical system consisting of a quantum dot with a short-range attractive impurity inside the dot are investigated in the zero-range limit. The Green function of the system is obtained in an explicit form. In the case of a spherically symmetric quantum dot, the dependence of the spectrum on the impurity position and the strength of the impurity potential is analyzed in detail. It is proven that the confinement potential of the dot can be recovered from the spectroscopy data. The consequences of the hidden symmetry breaking by the impurity are considered. The effect of the positional disorder is studied.Comment: 30 pages, 6 figures, Late

Animal Models in Myometrial Activity Research: Morphofunctional Features, Role of Oxytocin

One of the main functions of the reproductive system is providing the physiological process, which occurs by caudal spread of excitability of smooth muscle tissue and ensures delivery of the fetus. The results of this work confirm the importance of blood supply in automatism of the ovarian horn areas, which are the leading regions in propagation of electrical waves and coordination of other rhythmogenic loci. Morphofunctional methods have shown that the ovarian horn areas have strong vascularization, which is confirming the pronounced electrical activity of these loci. Oxytocin has a central role in changing of excitation patterns. Increasing hormone concentrations (10–2 μg/kg, 10–1 μg/kg, 1 μg/kg, 10 μg/kg) resulted in increase of the bursting activity duration of all studied myometrial areas. At the same time, rise in the frequency of spike rhythmogenesis was observed only at a dose of 1 μg/kg. Morpho-histochemical analysis revealed the existence of atypical cells with a high level of Ca2+-dependent acid phosphatase in both distal rhythmogenic ends of the horn. However, the ovarian horn area had the greatest enzymatic activity. Thus, the obtained data give good reason to conclude that the ovarian horn area has a leading role in the myometrium

Electrophysical methods of separation of metal cations in the moving salts solution

The results of experiments on the excitation of the phenomenon of selective drift of solvated ions under the influence of an external "asymmetric" electric field to the circulating solution of calcium chloride and magnesium salts in a polar liquid dielectric - water are shown. The purpose of the experiments was to determine the influence of the field frequency and amplitude of the field strength on the excitation phenomenon, and the study of the operating characteristics of the testing apparatus - a dividing cell. The dependences of the separation efficiency of solvated cations from the frequency of the external field and the excitation threshold of the phenomenon from the field strength in the separation cell are defined