Complements on log surfaces

More strong version of the main inductive theorem about the complements on surfaces is proved and the models of exceptional log del Pezzo surfaces with $\delta=0$ are constructedComment: 25 pages, Latex2

Buckling behavior of steel column with triangularly corrugated web

The paper presents a study of behaviour of axially loaded columns that consist of two flanges and a thin triangularly corrugated web, connected by automatic welding. In the literature, the buckling behaviour of steel columns was dealt with mostly for members with plate webs. Researches of that problem for columns with corrugated webs were found out to be very limited. A parametric study is carried out for various column slenderness and corrugation densities. A general-purpose finite element analysis software ABAQUS was used. The corrugation densities adopted in this study represent practical geometries, which are commonly used for such structures in building practice. Plot showing the influence of section slenderness on value of reduction factor for lateral buckling is presented. It is determined that existing buckling curves poorly describe the dependence of the reduction factor on slenderness for axially compressed members with triangularly corrugated webs. Finally, recommendations were proposed for the design of pin-ended columns with corrugated webs at lateral buckling in accordance with numerical results

Main Trends in the Development of Modern National Law

Article is about the main trends in the development of modern national law. And also, this article explores aspects, concepts, types of modern national law

Transverse load carrying capacity of steel triangularly corrugated web beam with opening

The paper presents a study of the transverse bending behaviour of corrugated web beam with and without web openings. Examined steel beams consist of two flanges and a thin triangularly corrugated web, connected by automatic welding. In the literature, the influence of web opening over transverse load carrying capacity was dealt with mostly for steel beams with plane, sinusoidal and trapezoidal corrugated webs, so researches of beams with triangularly corrugated webs were found out to be very limited. A parametric study is carried out for various web slenderness and corrugation densities. A general-purpose finite element analysis software ABAQUS was used. The corrugation densities adopted in this study represent practical geometries, which are commonly used for such structures in building practice. Models with and without web openings were analysed and examined in terms of load-deformation characteristics and ultimate web shear resistance. Recommendations are given for the practical design of corrugated web beams weakened by circular openings

RESEARCH OF CHANGE IN FRACTION COMPOSITION OF VEHICLE GASOLINE IN THE MODIFICATION OF ITS BIODETHANOL IN THE CAVITATION FIELD

The influence of bioethanol content and parameters of the cavitation field on the quality indicators of motor gasolines: volatility and octane number is studied. Studying the effect of bioethanol and cavitation treatment of bioethanol-gasoline mixture will make it possible to produce automotive fuels for different climatic zones, or winter (summer) versions of gasolines. The use of bioethanol and cavitation treatment of a bioethanol-gasoline mixture affect the fractional composition of motor gasoline and its volatility. The optimal content of the biocomponent, at which there is an increase in the volatility of gasoline, is established Also the results of the octane number change are presented depending on the intensity of cavitation treatment for gas condensate with the addition of bioethanol. The influence of bioethanol content on the increase in octane number during cavitation treatment is determined. It is found that the introduction of bioethanol into the composition of gasoline leads to an improvement in its volatility. In this case, cavitation treatment makes it possible to obtain a mixture resistant to delamination. The addition of bioethanol leads to an adequate increase in light fractions during mechanical mixing and to a change in the fractional composition of the bioethanol-gasoline mixture during cavitation treatment. The addition of bioethanol in amounts up to 10% leads to a decrease in the saturated vapor pressure during cavitation treatment of bioethanol-gasoline mixtures, and an increase in the bioethanol content up to 20% leads to an increase in the saturated vapor pressure, which is explained by a change in the chemical composition of fuel components in comparison with the mechanical method of preparing mixtures. By cavitation treatment it is possible to change the fractional composition, the pressure of saturated vapors and the volatility of bioethanol-gasoline mixtures, making cavitation a promising energy-saving process for the production of gasoline for various climatic condition