Article is devoted to strength calculations of compound designs. The deformed condition of the block under the influence of the external forces operating on a design, consisting of the basis in the form of the hexagonal plate which has been rigidly connected with the basis of a circular cylindrical cover is considered intense.
Keywords: plate, shell, the strength, the composite structure
An article about the history of the building material (aerated concrete), its composition, properties, applications. It describes the achievements of scientists in the field of gas-concrete products, which contributed greatly to the development of the construction industry around the world.
Keywords: concrete, blowing agent, structure, cement, plaster, foam, perhydrol.
Article is devoted to strength calculations of compound designs. The deformed condition of the block under the influence of any loading enclosed in its top is considered intense
Keywords: plate, shell, the strength, the composite structure
Article is devoted to strength calculations of compound designs. The deformed condition of the block under the influence of any loading enclosed in all its tops is considered intense
Keywords: plate, shell, the strength, the composite structure
"The mechanical properties of the rubber-cord composite in strengh analysis are described. There is an algorithm of the numerical estimation of the effective (average) properties of the rubber-cord. The effective properties are defined by the successive application of different deformations to the representative volume of the rubber-cord composite (tensions along each coordinate axis and shifts in each cooridinate planes). The effective properties are defined in form of the generalized Hooke's law (for anisotropic materials). A serias of computations in estimatition of the effective properties of double-layer rubber-cord composite was carried out based on the proposed algorithm. The dependence of the effective elastic modules of rubber-cord on the angle of cord was explored. The according graphs are represented in the article."
Keywords: theory of elasticity, effective properties, strength analysis, rubber-cord, numerical modeling, finite element method, CAE FIDESYS
The authors ground the expediency, prove the effectiveness and give an account of the basic points of rational technical decision about the use of a new resource-saving technology of inertial conveyor feeding of concrete mix and cement-sand grout to the point of placement while making concrete (cement-sand) cushions in the buildings with prepared or built-up roofings.
Keywords: roofing, concrete (cement-sand) cushions, concrete mix, concrete mix feeding, inertia conveyor, cost per unit of labor
In recent years reconstruction of buildings and constructions became one of the main directions in the field of construction. Considering that at reconstruction capital investments it is significantly less, and payback is higher, than at new construction, the share of capital investments in reconstruction will increase.
It is necessary to apply intensive methods of repair and reconstruction of buildings and constructions as one-time costs of reconstruction and repair there are less than one-time costs of new construction in construction production. Considering a significant amount of the factors significantly influencing the organization of construction at reconstruction of buildings and constructions, previously before development of organizational and technological documentation it is necessary to prepare the list of the data necessary for the organization of construction works and to make their analysis which concerns the analysis of projects and the territory of a building site, including situational plans.
Keywords: reconstruction, specifics of the organization, factors, systematization, analysis, feasibility study
Questions of improvement of the organizational mechanism of interaction of participants of construction are considered. In the conditions of weakening of state regulation, self-regulation with its collective joint liability of members of SRO has to become one of the main regulators of activity in the monitoring system of quality of construction. Ensuring integration of local systems of quality management of participants of construction has to be carried out on the basis of the regulations including requirements to system of document flow, to procedures of transfer, acceptance and modification of the design and estimate documentation, structure of executive documentation, an order of survey of the hidden works, requirements to information interfaces between local IT.
Keywords: Self-regulation, the organizational mechanism, quality management system in construction
Alzheimer's disease is an incurable illness. It affects about half a million people in Russia, and due to the general trend towards aging of the population the number of Alzheimer's disease cases will steadily increase. Insoluble deposits of amyloid beta in the brain tissue (amyloid plaques) are the major morphological characteristic of Alzheimer's disease. It has been found that the increased concentration of copper in amyloid plaques results in copper ions bound to the protein. It is the presence of copper in the binding site triggers of the formation of amyloid plaques. Therefore, the study of the binding site in amyloid beta is of great scientific interest. The local atomic structure of the Cu(I) copper ion binding site in the amyloid beta peptide has been studied by means of XANES spectroscopy. Several model structures obtained by molecular mechanics and density functional theory (ADF code) have been tested. Theoretical analysis of X-ray absorption spectra based on the finite difference method implemented in FDMNES code was performed. An appropriate model structure of the Cu(I) copper ion binding site in amyloid beta peptide has been found.
Keywords: amyloid beta, binding site, Alzheimer's disease, the method of finite differences, Cu(I)
We study the problems in the propagation of acoustic waves of a sound range near the boundaries of media. The features of the wave processes occurring at the water-air interface, due to the influence of inhomogeneous waves. Considered in detail the properties and parameters of an inhomogeneous plane wave. The mathematical calculations of the transmission coefficients L.M. Brekhovskikh for spherical and cylindrical waves through this boundary, allowing to take into account the contribution of inhomogeneous components. It is shown that than the frequency of radiation of a source is lower and the closer it is located to water-air interface, the acoustic transparency of this border is higher. Study of the dependence of the transmission coefficient of the water-air interface at low frequencies can have important consequences in a number of fundamental and applied problems. Increase the transparency of the interface requires a reassessment of the feasibility of acoustic communication from water in the air, the detection of underwater sources without dipping into the water and acoustic monitoring of the physical processes occurring in the water.
Keywords: Inhomogeneous plane wave, water-air interface, transmission coefficient, wavelength, spherical wave, acoustic impedance.
Features of a site of construction of constructions of seaport of Taman are considered. The settlement scheme of influence of new construction of point of loading on an existing complex of tanks is proved. The final and element model of a coastal zone with an arrangement of underground designs of existing and port constructions under construction is constructed. Results of calculation intense the deformed condition of the soil massif and construction designs are given.
Keywords: the pile bases, the soil basis, modeling, a deposit, intense the deformed condition.
The authors of the article examine the problem of electrothermal degradation of fiber optical communication lines arranged on the high-voltage power lines pylons. The possible methods of reduction of high-voltage line electric field influence on fiber optical communication lines were studied. There is also the method of possible calculation and choice of optimal suspension place for fiber optical cable on a high-voltage line pylon. This method can be applied for one of the high-voltage line masses disposition cases.
Keywords: electromagnetic field, thermal-electric degradation, fiber-optical communication lines, high-voltage power lines
Piezoelectric ceramics on the basis of the phase of (1-x) PbTiO3-xPbZrO3 is the basis of most high-performance piezoelectric materials. Electrophysical and mechanical properties of these materials can vary widely in different ways. Traditional methods include changes in composition within the morphotropic region and doping. Now is the study of the influence of topical makrolegirovaniya the material properties of the PZT system. As a model system was selected phase of the PZT system, the compositions of which MO belong, one of which contains a dopant in the sublattice (A) and another - in the sublattice dopants (B). The studies established that one of the effective ways of varying the parameters piezomaterials may be the formation of solid solutions on the basis of two or more piezoelectric phases having different combinations of electrical parameters
Keywords: Piezoelectric ceramics, doping, kombinorovanie, pezofaza, piezo
The analysis of causes of insufficient quality mathematical knowledge of students of technical colleges. There are formulated some problems which must be solved for the improvement of the quality of fundamental mathematical education in a technical university. It is introduced a notion of the system of adaptation of the first year students for studying high mathematical course. Elements of the realization of the adaptation system are described and main goals of this system are formulated. It is defined a technology of professional directionality of education in the fundamental mathematical preparation in colleges. It is described a content of the technology of the professional directionality of teaching mathematics which consists of regular demonstration of tasks, examples and models connected with the future professional work of students. It is given some results of the experiment of using in some colleges the technology of the professional directionality in mathematical education. It is analized the results of surveys on different steps of using the system of the professional directionality of education which are devoted to the level of students motivation to study high mathematics. It is supposed to involve undergraduate student into research projects in mathematics as one of the directions to improve fundamental mathematical education.
Keywords: fundamental mathematical education, system of student adaptation, technology of professional directionality of education
Describes the characteristics of the formation of zones zaschischayuschihlinii power, railways, roads, communication lines and other linear structures, passing through forests of trees and shrubs.
Keywords: Key words and phrases: trees and shrubs, protection, linear construction.