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Статьи журнала - Nanotechnologies in Construction: A Scientific Internet-Journal
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Arrangement of chemical elements in the three-dimensional matrix
Статья научная
It is emphasized in the article that thanks to the discovery of D.I. Mendeleev and the Periodic Table of chemical elements existing for more than 150 years, as well as the international table IUPAC, chemistry has been actively developing and keeps developing. A new model for arranging chemical elements in the form of a three-dimensional matrix has been proposed. This makes it possible to predict new elements with the designation of nuclear masses and the electronic structure of shells. There have been developed new patterns according to the cyclicity (block structure) of horizontal rows and the structure of vertical groups and their physical conception have been specified.
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Статья научная
Introduction. When using water suspensions of finely dispersed mineral systems of natural and anthropogenic origins as active agents in the production of concrete composites, an important factor in their effective use is to ensure the aggregative and sedimentation stability of solid phase particles before adding the solid phase into the reaction mixture. Methods and materials. The paper provides an algorithm for quantifying stability criteria according to the DLVO theory provisions as exemplified by a suspension of fine polymineral sand powder from the Kholmogorskoye deposit in the Arkhangelsk region (average particle size is 195 nm). In order to successfully assess the aggregative stability of this colloidal system, it is necessary to conduct experiments for determining the analogue value of the Hamaker constant, which was 0.5 •10–20 J for the mineral sand studied, in addition to experiments for determining the zeta potential of particles. This paper presents the results of the analysis according to the criteria of the value of the interaction energy (Uint) and the sedimentation rate (Vsed) of a polymineral sand dispersed system (water suspension) calculated taking into account the analogue value of the Hamaker constant, zeta potential and dimensional characteristics of its solid phase particles, physicochemical properties of the dispersion medium. Results and discussion. It is shown that the determining factor of the aggregative stability of the suspension is the electrostatic barrier for particle interaction. Theoretical calculation showed that the aggregative stability of the system may be affected by its particles reaching their zeta potential of approximately 10–4 mV (a nearly isoelectric state). It is proposed to use the kinetic parameter of sedimentation – its velocity – to assess the kinetic (sedimentation) stability of this suspension – resistance to gravity, i.e. the ability to resist the dispersed system stratification due to the difference in particle densities between the dispersed phase and dispersion medium. Conclusion. The sedimentation rate is Vsed ≈ 4 nm/sec for the object under study in water dispersion medium with the averaged dimensional characteristics of 195 nm. At such a rate of solid phase particle precipitation, a dispersed system based on finely crushed polymineral sand from the Kholmogorskoye deposit can be considered sedimentatively stable.
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Статья научная
Introduction. Activated sludge is one of thepulp-and-paper industry waste types. Within the framework of the rational natural resources’ utilizationand the waste recycling, due to its composition, activated sludge could be subjected to certain technological solutions for the production of nanofertilizers, since it has been previously the basis for making of various soils and biological products. However,occasionally the composition of activated sludge may contain different toxic compounds, heavy metals, and their impact on soil fertility and plants vital state is profound. Thus, the purpose of our research is to study the effect of the activated sludge introductionas a basis for nanofertilizers on the heavy metals contentin podzolic soils of various granulometric composition in agricultural exploitation. Methods and materials. Research was conducted under the conditions of dummy experimentin vegetation vessels. We have used podzolic soils of various granulometric composition (clayey, loamy, sandy) and pulp-and-paper industry waste – activated sludge in concentrations of 1; 2.5; 5 and 10% of the dried soil weight. Determination of the heavy metals gross content has been carried out by the atomic absorption method with measurement on the AA-7000 spectrophotometer (Shimadzu, Japan); mobile fraction of heavy metalsdetermination (подвижныеформы) – utilizing acetate-ammonium buffer solution by inductively coupled plasma mass spectrometry methodology. Results and discussion. The paper presents the results of the research on mobileand gross forms of heavy metals in podzolic soil of various granulometric composition when applying activated sludge as the basis of organic nanofertilizer under the dummyexperiment. Conclusion. It was shown that the content of mobile and gross forms of the studied metals (Fe, Mn, Cu, Zn, Ti, Al, Ni, Co, Cr, Cd and Mo) were within the health-based exposure limits, with the exception of Cd gross form, where the maximum excess was 2.5 MAC (maximum allowable concentration).
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Статья научная
The wettability of a surface of channels filtering liquids and gases under natural conditions of oil and gas reservoirs is one of the parameters that largely determines the filtration. A nature of the filtration channel surface wettability determines a phase permeability, capillary forces and intensity of adsorption at the interface. An ability of the filtration channel surface to be wet by the polar or nonpolar phases of formation fluid and process liquids affects the filtration-capacitive parameters of oil and gas saturated rocks. In this regard, in the development of oil and gas fields, much attention is paid to the study of physicochemical phenomena and processes occurring at the interfaces. An article presents the results of a set of laboratory experiments to study the surface activity of the colloidal system in the form of an emulsion with supercharged nanoparticles. A set of filtration experiments was carried out using the United States Bureau of Mines (USBM) method in order to assess an effect of the emulsion system with nanoparticles on wettability of the surface of oil and gas reservoir rock filtration channels. The research was conducted on rock cores of two oil and gas fields in the Ural-Volga region of the Russian Federation. According to the applied experimental procedure, rock cores were preliminarily maintained under reservoir conditions to give a surface of pore channels the properties close to the natural conditions. After that, the wettability of rocks was assessed by measuring the USBM wettability index before and after filtering the emulsion system with nanoparticles. Analysis of the research results showed that filtration of the emulsion system with high surface activity led to a change in the wettability of rocks from completely hydrophilic (USBM index – 0.60) to completely hydrophobic (USBM index – minus 0.32). The research results allowed to conclude that there is a high potential for application of emulsion systems with supercharged nanoparticles to control the filtration of formation fluids and process liquids in natural oil and gas reservoirs.
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