Nanotechnologies in Construction: A Scientific Internet-Journal

305-312

Authors: Zheldakov D.Yu., Kozlov V.V., Kuznetsov D.V., Sinitsin D.A.

To solve the problems concerning moisture behaviour in the material of construction’s enclosure, especially at alternating temperatures, is very important for the correct calculations of resistance to heat conduction of construction’s enclosure and, ultimately, for comfortable living conditions. However, there are still no methods for building enclosure’s materials that could determine the temperature of moisture crystallization in the material in solid phase. The premise of the research is that water incoming to the material of construction’s enclosure, presenting in the construction’s material in the form of oxides and salts, as a result of hydrolysis process of some elements, is an eutectic solution with unstable composition and concentration. Thus, the research of moisture crystallization process transfers from micro- area (when determining the temperature of crystallization by the size of material’s pores) to the nano- area when researching the eutectic solution at the possible condition of hydrates formation. The experimental technique was developed to perform laboratory research of the process of moisture freezing. The technique takes into account that freeze-thaw process of moisture in solid body is studied at significant difference between mass of liquid phase and mass of solid phase. The method was simplified for the broad use at working conditions. The simplicity of the method aimed at obtaining experimental resultsis compensated by the developed mathematical method of processing the results of the research. Mathematical solution of the problem based on the comparison of freezing curves behaviour of the samples in dry and humidified samples.

320-325

Authors: Vikhareva I.N., Zaripov I.I., Kinzyabulatova D.F., Minigazimov N.S., Aminova G.K.

One of the most demanded materials on the planet is plastic, the excellent performance of which contributes to the accumulation of a significant amount of waste on its basis. In this regard, a new approach to the development of these materials has been formed in scientific circles: the production of polymer composites with constant performance characteristics for a certain period and then capable of destruction under the influence of environmental factors. Analysis of the current state of the industry of polymeric materials shows that the most urgent is the use of such classical polymers as polyolefins and polyvinyl chloride. First of all, the optimal solution to this problem due to the lack of a suitable replacement for traditional polymers is the development of composites based on them with the use of biodegradable additives. In this case, a set of problems associated with waste disposal is solved: the decomposition period of the recycled waste is significantly reduced, the territories required for plastic waste are reduced. The paper outlines the preconditions for the emergence and further development of the field of biodegradable polymers. The main quantitative characteristics of the production capacities of manufactured bioplastics by types, regions and industries of application are given.

339-348

Authors: Bondar K.E., Shulaev N.S., Ivanov S.P., Laponov S.V.

Introduction. To use natural sources in rational way, plantsof continuous cooling of closed systems of recycling water supply are used. The paper presents designs of small-sized devices for recycling water cooling which are energy resource effective due to twisted motion of air flow, moving countercurrent to the cooled water. Heat and mass transfer is a nanotechnological process that occurs at the intermolecular level. Methods and materials. Countercurrent mini cooling towers are widely used in all industries, but there are some disadvantages, the main of which is the insufficient interaction time of the moving phases. Screw motion of air flow is created by the tangential supply of cooling air in the bottom part of cylindrical small-sized cooling tower. The rate of rotary motion decreases as air flow moves up in cooling towers, and vertical parameter of the rate – increases. Such scheme of the air flow motionmakes it possible to decrease average vertical parameter of the rate and to increase phases contact time. Laboratory research. To determine the technological and hydroaerothermal characteristics, as well as to estimate the efficiency of cooling recycled water, and to carry out mass-heat exchange at the intermolecular stagean experimental facility of small-sized cooling tower with twisted air flow has been developed. Conclusions. In accordance with the exponential law it is shown that the rotational component decreases at increasing height, and in accordance with the power law the vertical component increases component with the exponent ~1,79. It is determined that moisture content x and air temperature tv in the volume of the height of the sprinkler varies according to a power law, in particular for a screw cooling tower proportionally x ~ h0,83, tв ~ h1,25.