The authors have studied the physicochemical properties of aqueous dispersions containing carbon, silver, and iron nanoparticles which were produced by elastic-spark synthesis under the conditions of subaqueous spark discharge, and also the influence of preliminary acoustic and high-frequency electromagnetic action on them and the change in the functional indices of the glass-ionomer cement tempered by these dispersions.
The composition of complex hydrophobic plasticizer for portland cement concretes has been developed on the basis of wax-bearing emulsion and the hardening accelerator, and its behavior in portland cement mixtures has been studied.
We have studied the effect of the regimes of high-frequency (radio wave) electromagnetic treatment of gauging water on the process of structurization and on the technological characteristics of portland-cement systems. It has been established that the radio wave electromagnetic activation of water leads to a reduction in its surface tension, dynamic viscosity, and shear stress, as well as intensifies the formation of coagulation structures in a portland-cement slurry and aids in increasing the mobility of cement-sand mixtures.
We have investigated the influence of the regimes of high-frequency magnetic-impulse and acoustic action on the physicochemical properties of water solutions of polycarboxylate superplasticizers and technological indices of fine concretes plasticized by them. The dependences of technological properties of concretes on the concentration of water solutions of the superplasticizers, the content of impurity ions in the water used for dilution, and the conditions of acousto-radiowave treatment have been determined. The regimes of activation of superplasticizer solutions, which permit increasing the mobility and keeping quality of concrete and solution mixes tempered with water and the density and strength of fine concretes formed from them, have been established.
Influence of complex acoustic-radio wave treatment of water on an index of activity of ions of hydrogen, rheological specifications prepared by a cement-sand mixtures and technological parameters of the obtained plasticized fine-grained concrete studied. Two methods used to reach the maximum influence on an index of activity of ions of hydrogen of water, mobility, keeping of the prepared concrete compounds, density and durability at compression of concrete. The first method four -minute complex acoustic-radio wave treatment of water (high frequency (5.28 MHz) + ultra sound (44 kHz)), with the subsequent four minute additional impact of a high-frequency field. The second used method four-minute complex treatment of water (high frequency (5.28 MHz) + ultra sound (1 MHz)) with the subsequent two-minute additional impact of a high frequency field. Assumptions about the mechanism of acoustic-radio-wave activation of water and its impact on the process of hardening and structure of Portland cement systems are stated.
The effect of the complex acoustic-radio wave treatment of water on the index of activity of the hydrogen ions, the rheological characteristics of the cement-sand mixtures tempered by this water, and the technological parameters of the obtained plasticized fine-grained concretes was studied. Two methods were used to reach the maximum effect on the index of the activity of the hydrogen ions of the water, the mobility, the storability of the prepared concrete mixes, and the density and compressive strength of the concretes. The first method was a four-minute complex acoustic-radio wave treatment of the water (high frequency (5.28MHz) + ultra sound (44 kHz)) that was followed by the four-minute additional impact of a high-frequency field. The second method used was a four-minute complex treatment of used water (high frequency (5.28 MHz) + ultra sound (1 MHz)) followed by the two-minute extra impact of a high frequency field. The assumptions concerning the mechanism of the acoustic-radio waves activation of the water and the effect of this water on the process of hardening used and the structure of the Portland cement systems are expressed.
Formulations of composite retardands of flowability loss, based on a polysiloxane emulsion and an acid admixture, were developed. The influence of the content of the ingredients and of the sequence of introducing the superplastricizer and retardant on the technological properties of concrete mixes and concretes plasticized with Stachement-2000 polycarboxylate superplasticizer was examined.
The influence of the time of treatment of the tap and distilled water used for tempering of plasticized fine concretes by a high-frequency magnetic field on the technological characteristics of these concretes was investigated. The optimum regimes of treatment of the mixing water by this field and the dependence of the properties of the concretes obtained with it on the time of its storage after the treatment were determined.
Composites based on unwoven cellulose-hydrate and carbon materials and an organomineral binder have been developed and investigated. Optimal compositions of the composites feature a higher fire resistance, a low density, and effective thermophysical characteristics. The composites are promising for use as heat-insulating materials with a rigid structure in different branches of the national economy and industry.
Effect of various kinds of acids on the flowability and the flowability preservation time of plasticized cement-sand formulations and on the strength properties of the resulting materials was studied.
New complex plasticizing additives for mortars based on Portland cement, increasing the mobility of the cement paste and improving some technological properties of the resulting materials, were prepared.
The interaction between diglycidyl ether bisphenol A and conventional and water‐deficient phosphate binders has been investigated. The data of chemical analysis, IR spectroscopy, and differential‐thermal analysis point to the formation of a spatially cross‐linked epoxy polymer under the influence of the phosphate binders. It has been shown that conventional binders can be used as high‐temperature hardeners of epoxy oligomers. When water‐deficient binders are used, the formation of a three‐dimensional polymer structure is observed at room temperature.