Physical  principles  of  receipt  of  different  materials  range  of  properties.  PART  2
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Protect the surface of the concrete floor
To protect the concrete floor, which is operated in the normal mode, or is subject to wear in areas with high traffic, there are several ways to protect the surface.
   Comparable ways: their cost, appearance and ability to perform the task to protect.
   In this article, we consider three ways to finish and protect the floor. Each of them has its advantages and disadvantages.
  
   Thin fil...

Finishing compositions based on water glass. Part 3
When used as part of exhaustion moderator comes coagulation and solidification of liquid glass. However, due to the presence in the composition of Portland cement with a finishing time is an increase strength of the coating due to hydration of cement minerals. Thus from colloids formed during the coagulation liquid glass are actively assigned to the water for hydration of cement, a porous media formed tumors filled Portland cement, which leads to...

Finishing compositions based on water glass. Part 2
Studies in Berlin Institute Federal institute for Materials Research and Testing, show that the average density of 1730 kg/m3 brick large proportion of pores having a size in excess of 1 micron is more than 90% [3] and they are responsible for the increased migration of fluids through brickwork.
   Most fully meet these requirements structure obtained by coagulation and water-soluble potassium silicate forming silica with a high sp...

Modernization and repair of self-propelled machines. (3)
Hardening electrolysis BORATING hinge pins and bushings mates working equipment hydraulic excavators EO-4121 (EA-4321) gives an increase in wear resistance 4-6 times compared to the bulk quenching details.
   Taking into account the high wear resistance of brazed blades, hardened sintered alloys (see Table 1), are recommended for carbide knives dumps graders DZ-122 and RS-98, combined machine E-405 based on KAMAZ, for front dumps a t...

Specialized exhibition Architecture. Construction (END)
Mari-lime brick and gas silicate blocks
   JSC "MZSK" produces silicate brick and a half, color (white, yellow, black, red, blue, green, brown).
   For the production of silica brick used quartz sand from quarries near the plant. Limestone enters the factory with Dobryatinskogo deposit Vladimir region. Silicate brick (Table 1) is used for masonry exterior and interior walls of buildings and structures, as well as ...

Geophysical processes primers and security. Part 5
In the center of Moscow can distinguish vertical structure comprising a crashing into the Earth`s crust magma elongated cylinder (Fig. 2) [5]. In the center section marked lack of extensive vertical zone converted waves ("blind spot"), going from the depths of 70-80 km to 7.5 km. Such "blind spots" are characteristic of the earth`s crust with the introduction of monolithic dense mantle rocks such as gabbro, diabase, etc. In such a zone Tashkent e...

Finishing compositions based on water glass. Part 1
The quality of the decoration of buildings for new construction and reconstruction depend not only on their aesthetic, but also the operational parameters, as good-quality finish - a guarantee of durable service basic designs, long maintenance-free operation, the costs for maintenance and care. Traditional binders used for the production of finishing compositions, liquid glass is widely used, but it has some drawback: coatings based on it gaining...

On possible amendments to the equation Griffiths
Griffith presented a picture of destruction allowed to formulate the problem of determining conditions of the beginning of crack propagation and find its general solution.
   As seen from the above schemes, in the process of crack propagation material directly adjacent to it "coasts" unloaded relaxes. This means that the stress and strain it decreases, and the elastic energy stored earlier in this area of ​​the body is re...

Construction skyscrapers - the requirements of modernity. Part 4
The program is a high-rise building in Moscow
   The project is now a high-rise building in Moscow is implemented in two main areas: the construction of business center "Moscow City" and implementation of the program of the Government of Moscow "New Ring of Russia."
   1. Moscow international business center "Moscow - City"
   The project includes the construction of buildings on the territory of abou...

Degree project - beginning of the road. (3)
Given the great diversity of subject matter and content of diplomas in various specialties, the jury is faced with great difficulties in determining the winners - "Who better violinist or a dancer?". Nevertheless, often based on emotional perception and can estimate the relevance and novelty, and the author`s contribution to the thesis project or job. Absolute winners in recent years have been graduates of Rostov CSO GASU St. Petersburg, Nizhny N...

 

 
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 Physical  principles  of  receipt  of  different  materials  range  of  properties.  PART  2

The second way - the creation of polytropic materials, ie another, more ambitious level of consideration of the total composition. They are composed of layers and can be "dialed" separately or simultaneously. While addressing, since material can be obtained, for example, two-layer, each layer of which - heavy concrete and lightweight - will unite
   dispersion medium in the form of hardening cement and featuring only a placeholder - solid or gaseous.
   Assume that the heavy concrete with a heatproof hard foam - covering the right size can be quite easily obtained with simultaneous or close in time hardening. The number of layers, generally speaking, can not be limited to two, but the song itself should win the properties also because the heat generated by the concrete slowly reaching reactions until exhausted thermodynamic reserve (4) accumulates coated and thus preserved. Thus it is possible to obtain a uniform wall polyfunctional material nature.
   Fracture mechanics of such structures is different, because it contains more reserves to dampen tensions.
   But this kind of symbiosis may be considered for another song: cement mortar - bricks. Create aerated solution
   would give the whole structure a high heat-shielding performance
   and would bring CTE materials, which also would affect longevity.
   Next, we believe, a special characteristic of materials of the third millennium, which also involves prirodosohrannost through longer product life (for example in corrosion by stray currents), as well as by manufacturing products having reduced power consumption during operation. In the first case, determining a property of materials are the dielectric properties, while in the second - conductivity. In our studies the technology of manufacturing glowing concrete, which reclaims the operation of road and railways high extent.
   Concrete is glowing electroluminescent light source and is a system of electrically conductive concrete and the electroluminescent coating with a new property for the concrete product - emit light under the influence of an alternating electric field. Electroluminescent coating may emit light of any color, including white. Furthermore, the coating has moisture-and maslozaschitnymi properties. Electroluminescent light sources (ALICE) based powder phosphors are becoming increasingly popular due to the low power consumption (5mVt/kv.sm), small size and weight of the product as well as the possibility of forming large luminous surfaces of complex geometry. With ALICE can create still and moving visual images of any shape, change their color and brightness. Scope ALICE - this color pointers, Mimic, emergency lights, advertising and decoration means premises. Design
   ALICE includes dielectric electroluminescent and functional layers, which are enclosed between transparent and opaque electrodes (5). As the electrode substrate used
   conductive concrete, and other functional layers as
   - ALICE-filled polymers. For conductive concrete as
   binder used Portland
   Pikalevsky factory HRC 400-. Conductive component were iron and tungsten powders, and carbon black. Reduced shrinkage stresses samples ensured using conductive concrete aggregate - natural quartz sand in a natural state, or ground and shungizitovogo sand obtained by crushing shungizita to a grain size less than 5mm. Mobility mixtures corresponded blurring cone 120mm.
   The introduction of conductive fillers reduces volume resistivity of concrete (in comparison with a control formulation number 5). The smallest resistivity has concrete containing, besides the conductive filler, filler carboniferous - shungizitovy sand. This composition was used to produce glowing concrete. A known method of reducing the electric resistance of concrete is the use of rigid compression mixtures (6). And in our study researches and reduced water-cement ratio and styling mixed with application load accompanied by a decrease in the resistivity of 80 ohm / m method of manufacture of the product was as follows. First prepared electroconductive substrate concrete. Then, by casting it applied consistently dielectric, electroluminescent functional layers and the transparent electrode. To increase the weathering product coated with a sealant. Next to the sample conductive glue stuck wires.
   Concrete pillars catenary, "dressed" in a solid foam, significantly increase their dielectric properties, which has ecological importance as the fight against stray currents and conservation materials.
   Another principle that I would like to touch, resulting in a durable materials - this catalysis durability. It is obvious that, in order to slow down the chemical interaction of the material with the environment, it is necessary to increase the activation energy of the interaction of the material - the environment that can be achieved by catalysis, in this case negative. The presence of such substances in the system is a kind of "watchman". They do not allow the passage of the main reaction or slow down long enough for her, increasing the energy barrier of the beginning of the process. In materials science plays a major role heterogeneous catalysis. Within the framework of classical kinetics can be argued that in substances should provide a greater activation energy of interaction than its value for direct main reaction. Thus, if the level of the main reaction of material destruction meets the activation energy EA1 and catalyzing agents when administered in the activation energy has velchiinu EA2, the difference E =-EA1 EA2 is kinetic reserve KRD durability, and the scale of it is, the slower the be breaking stuff. Because the hardening occurs as a system redox and acid-base reaction, but also the durability of the catalysts, i.e. substances introduced in advance, retard degradation rate can be of two types, respectively - the redox and acid-base. The system of knowledge about the activation energies KRD is a function of the quantity E and has as a unit amount of energy, ie can bind kinetics, thermodynamics and the nature of the substance into a single strength relationship.
  
   REFERENCES
   1. Svatovsky LB Engineering Chemistry. Part I - SPB., PGUPS, 1995, 95c.
   2. Svatovsky LB, VY Soloviev, Maslennikov LL Engineering chemistry and others. Part 2. - St. Petersburg., PGUPS, 1998, 105 p.
   3. Latutova MN Svatovsky LB, Makarova O. Unburned clay and glazes mosaic. In Sat nauchn.sta children "Contemporary Problems of Ecology at the w / d of trans-port." - St. Petersburg., PGUPS, 1999
   4. Svatovsky LB Thermodynamic reserve strength / Cement, 1996, 1, p. 7 ... 8
   5. IK Vereshchagin, Kovalev BA, Kosyachenko LA, SM Kokin Electroluminescent light sources. - M. Energoatomizdat, 1990, 168 p.
   6. Pugachev, GA Manage the conductive properties of concrete on the basis of structural and energy modeling. Author`s abstract of dis. dts Moscow, 1990, 43c.
  

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