Water quality analysis and simulation

The actuality of the study is caused by the needs of water resources state assessment, which natural supply is insufficient. The article analyzes the quality of surface water and groundwater using processed statistical data and the results of mathematical modeling in the GIS environment. The results showed that the quality of water sources under current anthropogenic load is normal, but subsequent monitoring of the situation is required. There is no significant relationship between the quality of surface water and groundwater

Stable Lithium Argon compounds under high pressure

High pressure can fundamentally alter the bonding patterns of chemical elements. Its effects include stimulating elements thought to be “inactive” to form unexpectedly stable compounds with unusual chemical and physical properties. Here, using an unbiased structure search method based on CALYPSO methodology and density functional total energy calculations, the phase stabilities and crystal structures of Li−Ar compounds are systematically investigated at high pressure up to 300 GPa. Two unexpected Li(m)Ar(n) compounds (LiAr and Li(3)Ar) are predicted to be stable above 112 GPa and 119 GPa, respectively. A detailed analysis of the electronic structure of LiAr and Li(3)Ar shows that Ar in these compounds attracts electrons and thus behaves as an oxidizing agent. This is markedly different from the hitherto established chemical reactivity of Ar. Moreover, we predict that the P4/mmm phase of Li(3)Ar has a superconducting transition temperature of 17.6 K at 120 GPa

A FEM Modeling of the Concrete Pavement Made of the Recycling Material

Paper is a brief review of the research focused on formulation an numerical model for the concrete pavement which is made by the recycling material. For numerical modeling the finite element model (FEM) and the 3D finite element model were applied. The software EverFE 2.25, was used. The results of FEM analysis is in a chapter shape showing move value change, strees and deflections for all layers a construction road model. In the next phase of the research was provided by FEM software with appropriate general purpose non-linear models, which allows the analysis of the real behavior of solid pavement under load

The problems of calculating the load-bearing structures made of light steel thin-walled profiles

The article presents the results of a study of bearing capacity of thin-walled cold-formed steel beam of the guide profile. Such profiles have a small thickness and complex cross-sectional shape. Bending deformation develops in the cross-sectional plane under the influence of loads in beam. In addition, deformation of constrained torsion and warping arise. These deformations influence the stress distribution at the points of the cross-section of the beam and thereby determine its load-bearing capacity

The problems of calculating the load-bearing structures made of light steel thin-walled profiles

The article presents the results of a study of bearing capacity of thin-walled cold-formed steel beam of the guide profile. Such profiles have a small thickness and complex cross-sectional shape. Bending deformation develops in the cross-sectional plane under the influence of loads in beam. In addition, deformation of constrained torsion and warping arise. These deformations influence the stress distribution at the points of the cross-section of the beam and thereby determine its load-bearing capacity

Applicability Problem in Optimum Reinforced Concrete Structures Design

Optimum reinforced concrete structures design is very complex problem, not only considering exactness of calculus but also because of questionable applicability of existing methods in practice. This paper presents the main theoretical mathematical and physical features of the problem formulation as well as the review and analysis of existing methods and solutions considering their exactness and applicability

Assessment of the Investment Appeal of Hydropower Construction Based on the Analytic Hierarchy Process

The purpose of the paper is description of the method of estimating the investment appeal rate of hydropower construction in the federal subjects. The method is based on Analytic Hierarchy Process (AHP). According to the method every federal subject is estimated by the decision-maker. The authors collected data for this study from Russian Federal State Statistics Service, the Federal Subjects Development Programs and the Power Industry Development Programs of the federal subjects (23 indicators). The federal subjects were estimated according to these indicators. As a result of this project every estimated federal subject has status: attractive, relatively attractive and non-attractive for hydropower development. The results can be applied to calculate the economic hydropower potential. The method was tested for detecting the attractive federal subjects of the Volga Federal District, North Caucasian Federal District, Northwestern Federal District, Siberian Federal District for hydropower development