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  • Processes of neopentylglycol extraction from the aqueous-organic systems Part I

    The results of the solubility research of the polycomponent water organic systems with neopentylglycol, sodium formate and organic solvents are presented. The temperature concentration parameters of the extraction and crystallization processes of neopentylglycol and sodium formate are identified on the bases of the solubility diagrams obtained, the technological diagrams of the processes are given theoretical basis and enlarged laboratory experiment was carried out.

    Keywords: neopentylglycol, aqueous organic systems, solubility diagrams, extraction, crystallization

  • The Experimental Research for the Development of The Data Base of Mineral Waters

    The technologies of getting energy from the unlimited sources render possible to build the energy-independent houses with the ecologically clean infrastructure in remote areas and to solve the problems of the energy supply of the already-existing objects. In Azerbaijan and in Russia the mission-oriented research is carried out as both countries have either traditional or alternative stored energy sources, and much work is in progress on the parallel development of modern technologies of energy providing of human life support including technologies based on the use of mineral waters which are of interest in the field of bioengineering resources. The primary chemical and thermophysical properties of mineral waters underlie in creation of the technologies of the use of their resources. The special investigations on the determination of chemical properties of mineral waters of separate regions of the Stavropol Territory of the Russian Federation are substantiated and assumed in the article. In the paper the experimental works of the chemical composition of nine mineral waters of the sources of the regions of Pyatigorsk and Yessentuki cities are carried out by the methods of experimental atomic emission spectroscopy and ion chromatography. The major part of the established chemical elements includes sodium (Na) (from 844 up to 6620 mg/liter); then calcium (Ca) as one of the main sources of cations, and also kalium (K) and magnesium (Mg) (they compose from 6.7 up to 92.2 and 15 up to 76.2 mg/liter correspondingly). Sulfur (S) is also important with the quantity of 362 mg/liter; silicon is in sufficient number as part of these mineral waters – from 3.5 up to 27.3 mg/liter. The small part includes lithium (Li), boracium (B) and strontium (Sr). The findings render possible to expand the world data base of the corresponding natural resources of the Russian Federation for the development of the ecologically oriented technologies.

    Keywords: Mineralnye Vody, chemical composition, pilot studies, nuclear and issue spectroscopy, ionic chromatography

  • Progress in elaboration of nonisocyanate polyurethanes based on cyclic carbonates

    In the article is given a review on production and application nonisocyanate polyurethanes based on cyclic carbonate oligomers. Nonisocyanate polyurethane (NIPU) networks are obtained by reaction between the polycyclic carbonate oligomers and aliphatic or cycloaliphatic polyamines with primary amino groups. This forms a crosslinked polymer with β-hydroxyurethane groups of different structure – polyhydroxyurethane polymer. Considered as a proper NIPU and hybrid polymers, involving various other oligomeric systems (HNIPU). Significant attention was paid to the materials based on renewable raw materials.The authors give an overview of recent publications in the field with a more detailed description of the Polymate Ltd. achievements.

    Keywords: nonisocyanate polyurethanes, cyclic carbonates, polyhydroxyurethane polymer.

  • Monolithic flooring based on reactive oligomers

    Development of new industries, especially in the chemical, petrochemical, electronics, mechanical engineering industries and nuclear power, put forward the need for flooring with a specific chemical resistance, with minimal sorption in mild decontamination; significantly increased the need for dust-free floor coverings. The paper defines the requirements for materials for solid flooring; take into account the specifics of the polymer cements and mortars in the floor construction, as well as lists developed after various formulations for flooring.

    Keywords: solid flooring, reactive oligomers, stress, strain, composition for flooring.

  • Nanocomposite organic-hybrid materials

    In this article is reviewed the nature of organic hybrid nanocomposites. Promising directions in the field of organic hybrid nanocomposite materials will be methods for the synthesis of multicomponent materials, as well as the type of "net net" and "host-guest". The fundamental problem with the chemistry and physics of nanocomposites is dependent "structure-property". Solving this problem will move from research materials to their purposeful design.

    Keywords: nanocomposite sol-gel technology, synthesis, nanoparticles.

  • Modeling of changes of physicochemical characteristics of potash fertilizers at storage and transportation

    A model system was designed and test  trials of physical and mechanical characteristics of small – crystalline and granular flotation potassium chloride are studied. This model system allows to design storage and transportation  of fertilizers in bulk in railway wagons and it has the same static and vibrational load as real system. The effect of temperature and relative humidity of the air on hygroscopy of small – crystalline and granular КСl were studied. Furthermore the influence of static load, and time length  of compression process of fertilizing layer and parameters of static and vibrational load on composition of КСl granules were investigated. It was experimentally proved that the humidity increase (0,5 %) of granular КСl and the  increase of static load and time length  of compression process of product during transportation in bulk lead to increase of compaction degree and caking ability of product. Research of the influence of high static load (10-30 kg/sm2) and time length of compression process of fertilizing layer on caking ability and degree of compaction show that small – grained KCl has smaller degree of compaction and considerably higher value of caking ability in comparison with granular KCl.

    Keywords: Potash fertilizers, storage and transportation, hygroscopy, caking ability, degree of compaction, commodity characteristics of fertilizers

  • Nonstoichiometry and electrochromism of oxides and polyalkaline tungsten bronzes

    Nonstoichiometric tungsten oxides WO3–x and oxide alkaline tungsten bronzes have been studied because of their potential applications in electrochromic devices such as solar panel arrays and “smart windows”. Different phases of 
    WO3–x have been considered. In this part we present results of our research which clearly show that all Magneli phases of tungsten oxides  WOx (namely W40O118, W20O58, W5O14, W18O49, W8O23, W3O8) and oxide tungsten bronzes MxMyWO3 at M-Li, Na, K, Rb, Cs. They are characterized by metal – like properties. Their band structures display an energy gap in the valence band just below the Fermi level.
    We present results of our electrochemical synthesis of tungsten oxide bronzes in ionic melts of the polytungsten salts. Among the new state – of – the art methods for their manufacture, electrochemical synthesis in ionic melts, which  makes considerably better use of existing technologies, is highly productive, based on the discharge of oxyanions of the polytungstates.  

    Keywords: oxide alkali bronzes, alkaline tungsten bronzes, tungsten, molybdenum, nonstoichiometry, tungsten oxides, electroconductivity, electrochromism

  • Liquid glass and aqueous solutions of silicates, as a promising basis for technological processes of new nanocomposite materials

    The properties of the water-soluble high-modulus silicate systems: based on alkali metal polysilicates called liquid glass and chain their transformation from lower to higher oligomers, with the subsequent formation of colloidal solutions - silica sol. The methods of preparation, properties and applications of water-soluble high-modulus silicate systems. The possibilities of their use as a binder and modifying agents for various nanostructured composite materials. The examples of promising areas of application of liquid glass and high modulus of aqueous solutions of silicates in construction and industry. In particular show the possibility of using liquid glass and aqueous solutions of silicates in the production of nanostructured silicate polymer. In space engineering for manufacturing water-destructed mandrels used in the manufacture of solid rocket motor casings and pressure vessels 'cocoon' of composite materials by winding. The application of the inorganic sol to obtain a nanocomposite ceramics and monolithic blocks of silicon oxide, which can be used in various fields of modern technology. The possibility of using silica sol as a binder for refractory ultra-lightweight shielding materials used to protect equipment from high impacts. The directions of development of the production of new acid-resistant materials and linings for protection of chemical equipment, parts and components operating in corrosive environments.

    Keywords: Keywords: water glass, silicate polymer concrete, additives, silicates organic bases tetrafurfuriloksisilan, furfural alcohol, nanostructure composite materials, water-soluble silicates, silica sol, sol-gel transition, cured xerogel water-destructed mandr

  • Features of obtaining manganese dioxide by method thermolysis on the tantalum anode of condenser

    In the article obtaining of cathodic coating MnO2 on condenser porous tantalum anode was researched. It was ascertained that formation of crystalline defects from hydrated MnO2 on MnO2 coating obtaining by known technology is possible. Such formations disturb tantalum capacitor cathode integrity. To determine the reasons of the crystal defects formation conveyed simultaneous thermal analysis of Mn(NO3)2x4H2O and Mn(NO3)2x6H2O with an analysis of the flue gases by FTIR spectroscopy. Based on the analysis results a mechanism of manganese nitrate thermolysis was suggested and the cause of the crystal defects on the surface after the coating of manganese dioxide removed from the furnace was ascertained. It was established that the thermolysis process is followed by the formation of such manganese nitrate intermediates as manganese hydroxynitrate, manganese oxyhydroxide and its further oxidation to manganese dioxide. Because of secondary processes leaking on the MnO­2 cover manganese oxyhydroxide residual can react with water vapor and oxygen, that leads to the formation of crystalline defects. Such phenomenon has a negative impact on the chemical composition and integrity of the coating on the surface of the porous MnO2 tantalum capacitor anode. Also it has been found experimentally that manganese hydroxynitrate is formed from manganese nitrate in the form of microtubules on the porous tantalum vehicle surface.

    Keywords: manganese dioxide, coating, manganese nitrate, thermolysis, crystalline defects, microtubules

  • The physicochemical analysis NH4NO3 – KNO3 – Н2О system at 25 degree C

    In the article are introduced research results of physicochemical properties of ammonium nitrate – potassium nitrate water system at 25o C. The literary source analysis is performed that no clear opinion about solid phases composition. The different composition double salts, solid solution and eutectics are identifies. Appeal is specifies a look and properties of formed structures. Methods of differential thermal analysis and X-ray diffraction have been establishing that the equilibrium solid phase of the studied system represents two types of solid solutions. A first type based on the III phase of ammonium nitrate crystal latitude (at the content of nitrate of potassium to 20 %) and a second type based on the potassium nitrate rhombic syngony (at the content of nitrate of potassium more than 80 %). Crystal cells parameters of being formed phases submit to the Vegard rule. The ammonium nitrate sample (at the content of nitrate of potassium more than 12 %) keeps phase stability at the temperature range minus 50 to plus 100о С. Burst in components miscibility at the potassium nitrate concentration range 30 to 80 % is observed.

    Keywords: ammonium nitrate, potassium nitrate, differential thermal analysis, X-ray diffraction, cocrystallization, solid solution

  • Features of the spinel phases formation in system NiO – CoO – CuO – Cr2O3

    The combination of the unique, abnormal properties shown by oxidic systems with structure of spinel on the basis of transitional elements chromites draws attention of researchers for many years. Some systems on the basis of transitional elements chromites (for example, nickel and copper chromites) have critical elements (multicritical points, lines of phase transitions of the second sort, etc.) on the phase chart. Near these elements of the phase chart materials possess unique chemical and physical properties. Therefore development methods of receiving and research of phase forming and properties in NIO-CoO-CuO-Cr2O3 system represent fundamental and practical interest for chemistry and technology of inorganic substances. In this work processes of spinel structure formation in system 0,6 NiCr2O4 – 0,2 CoCr2O4 – 0,2 CuCr2O4 from crystal chemistry positions are considered. Formation of two solid solutions on the basis of nickel (II) chromite – with structure of cubic spinel and with tetragonal distorted structure is established. The influence of cooperative Yahn-Teller effect on processes of a spinel forming and on stabilizing impact of chloride of potassium on process of education of  two spinel solid solutions is suggested. Influence of a power factor of cation stabilization in knots of a crystal lattice as one of the important factor in reaction of spinel structure formation is considered.

    Keywords: spinels, chromites of transitional elements, Jahn-Teller effect

  • Comparative study of the catalytic activity Pt/C and PtхNi/C materials in the oxygen electroreduction

    The catalytic activity of Pt/C and PtxNi/C electrocatalysts prepared by  borohydride methode was studed. It was established that the specific activity  of fresh prepared Pt3,7Ni/C  catalyst  in oxygen  electroreduction  reaction is higher in compare with Pt/C material. After treatment of Pt3,7Ni/C material in the hot acid  nickel in the surface layers of nanoparticles was dissolved and the composition of nanoparticles was changed to Pt5,6Ni. The electrochemical surface area of the Pt5,6Ni catalyst and specific activity was slightly decreased after corrosion treatment. 

    Keywords: platinum electrocatalysts, corrosion stability of the nanoparticles, fuel cells, X-ray diffraction, borohydride synthesis

  • Investigation of the possibility of using hydrocyclones for centrifugal flotation of potassium-containing ores

    The possibility of using hydrocyclones combined action principle for the classification of potassium-containing minerals. The results of studies on the structure of the bubble layer in the aeration chamber. Describes the new design of hydrocyclones-flotation.

    Keywords: hydrocyclone, skimmer, air core, aeration chamber, flotation, sylvinite

  • Complex research of the composition and structural characteristics of the rock-forming minerals in Millerovsky bentonite clay

    This work deals with the integrated study of the composition and structural characteristics of the rock-forming minerals in Millerovsky bentonite clay. The qualitative and quantitative analysis of the clay samples is made by X-ray diffraction , X-ray photoelectron spectroscopy and thermal analysis . The morphological and microstructural features of minerals are investigated by scanning electron microscopy. The application of the method of direct theoretical calculation of the diffraction patterns is showm to determine the crystal-chemical parameters of the studied minerals. The results are aimed at explaining a number of physical and chemical properties of layered aluminosilicate.

    Keywords: clays, clay minerals, layered silicates, x-ray diffraction, crystalline systems

  • Experiment planning on thermal power plant fly ash collection in elektrocyclone

    The article deals with the design of experiments for dispersed particles capturing in elektrocyclone. The autors gives planning matrix calculation, the regression equation based on the aerosol velocity and the initial concentration of the aerosol and plot of function.

    Keywords: gas cleaning; cyclone; elektrocyclon; fly ash

  • Kinetics of sylvinite ore desliming under ultrasonic treatment

    Operation of sylvinite ore desliming is an important step of potassium chloride production by floatation method. It is known that ultrasonic treatment is applied to increase the efficiency of insoluble rest separating from an ore. The purpose was to establish kinetic regularities of the insoluble rest removal from sylvinite ore crystals of the same particle size distribution. Investigations were carried out with mechanical stirring and sonication of varying intensity. It is established that process of sylvinite ore desliming occurs in the diffusion mode. Application of ultrasonic treatment allows to intensify process in 2-4 times as compared with mechanical desliming. Influence of sylvinite ore treatment parameters to chemical composition changing of the insoluble rest is defined. It is shown that sonication for 90 seconds leads to removing carbonates from ore crystals withal concentrating of the iron compounds.

    Keywords: desliming, sylvinite ore, ultrasonic treatment, sonication, insoluble rest.

  • Influence of the manganese nitrate surface phenomena characteristics on impregnating tantalum capacitor anode

    The influence of manganese nitrate impregnating solutions concentration and temperature dynamic viscosity, the wetting angle, interface “porous tantalum electrode - solution” free surface energy and the impregnation degree of porous tantalum anode was researched. A quantitative characteristic of manganese nitrate solution application on porous tantalum anode of solid-electrolyte capacitor during the process of impregnation was defined and work of adhesion and cohesion was calculated. Thus increasing of solution concentration above 42% wt brings to sharp growth of surface tension and so work of cohesion is increased but carriers impregnation is fallen. The most effective impregnation is realized at concentration 27% wt. This fact corresponds to best value of tantalum anode capacitor free surface energy. So using received data we are able to estimate optimal conditions of impregnation and wetting process by nitrate magnesium.  

    Keywords: manganese nitrate, manganese dioxide, limiting wetting angle, free surface energy

  • Thermostability of oxide alkali tungsten and molybdenum bronzes

    Oxide bronzes MxEO3 (M–Na,K; E – W,Mo) are the inorganic materials for technics and chemical technology. Its properties, for example stability in wide interval of temperatures, are of great practical interest (electrodes for fuel elements, electronic apparatuses  and others).                                                                             In this article the results of studies of thermostability of sodium and potassium tungsten and molybdenum bronzes in atmosphere and vacuum condition at the temperatures range 20-1110°C were found. The samples are prepared by electrolysis of melts of sodium and potassium isopolytungstates and molybdates. Dates for bronzes Na0.92WO3 , Na0.68WO3 , Na0.53WO3 , Na0.15MoO3, K0.3MoO3 were characterized by the termogravimetric-differential- thermal analysis (TG-DTA). Regions of stability of Na0.92WO3 : 20-700°C , of MxMoO3 : 300-500°C were founded. Conclusion about correlation of  nonstoichiometry of chemical composition of EOx bronzes and oxides, which making important role in formation of less - common metal bronzes structure.

    Keywords: oxide alkali bronzes, tungsten, molybdenum, thermostability, nonstoichiometry, thermal analysis

  • Methods for the synthesis of LaMnO3 (Review)

    "This review covers various methods of synthesis LaMnO3 ferroics. The general analysis of the solid-phase synthesis reactions methods and wet methods (sol-gel, sorption, co-precipitation) are carred out. The original results of LaMnO3 syntheses from various precursors by means of the in situ method are showned. The advantages and disadvantages of different methods of synthesis are determined. The analysis of synthesis LaMnO3 ferroics published data is shown:
    - the structure formation of LaMnO3 in perovskite-type phases occurs at different temperatures, depending on precursors states;
    - LaMnO3 perovskite phases differ in symmetry and unit cells parameters at room temperature, depending on the preparation conditions;
    - the highest synthesis temperature of LaMnO3 are typical for solid phase reactions method (950-1050 ° C), the lowest - for wet synthesis methods (500-700 ° C);
     - the synthesis conditions effect the stoichiometry of LaMnO3 for oxygen content.
    Our studies of structure formation processes of LaMnO3 by in situ method are allowed to define the role of precursors states at synthesis of solid phase reactions methods, adsorption, co-precipitation and sol-gel mixtures.
    It is determined that in samples prepared by wet chemical methods, the formation processes of  LaMnO3 perovskite phases occur at lower temperatures than by solid phase reaction (sol-gel precursor - 500 <T <600 ° C; precursors obtained by coprecipitation and sorption methods - at 600 <T <700 ° C and 700 <T <800 ° C, respectively).  

    Keywords: ferroics, LaMnO3, X-ray diffraction, solid-phase synthesis, sol-gel synthesis, sorption, co-precipitation

  • Flexible piezocomposites with mixed connectivity phases in the system

      Laboratory technology was developed to fabricate flexible piezocomposites with ferroelectric phase - polymers having signal reception factorv • gv 5000 • 10-15 m2 / N. The values of the given coefficient were achieved by switching from a probabilistic (spontaneous) percolation to a correlated one in the process of forming material. This made the production of 0-1–3 piezocomposites, in which a part of piezophase has 0 connectivity, and the other part – 1 connectivity possible. To improve the efficiency of piezocomposite polarization before their manufacturing the surface of piezophase particles, which were obtained by the partial destruction of the porous frameworks, was treated with coupling agent, which did not only improve the polymer adhesion to piezophase, but also allowed the removal of water from the particle surface. The latter effect reduced the value of interfacial conductivity, i.e. prevented the voltage drop of the polarizing field. Matching of polymer conductivity and piezoceramic particles by determining the optimal polarization temperature was carried out as well.  

    Keywords: piezocomposites, percolation, connectivity, electrophysical properties

  • Research of process of drying of conversion lime carbonate in a tube-dryer

    In article findings of investigation of process of drying of conversion lime carbonate in an air-operated tube-dryer are resulted. For the first time dependences of moisture content in a tube-dryer from reference temperature of air or gases and from length of a tube-dryer are received. Results of researches can be used for designing of tubes-dryers for large-tonnage productions of conversion lime carbonate. 

    Keywords: conversion lime carbonate, drying, tube-dryer

  • Research of process of wettability of pulverulent potassium chloride containing the admixtures of flotoreagents

    The express-method of estimate of the rate of wetting  of pulverulent powder of KCl is developed. The wettability of potassium chloride powder containing the admixtures of flotoreagents by solutions of different binders is studied.

    Keywords: wettability, flotoreagent, binder, transformation, muriatic amine, sodium metasilicate

  • System ammonium purpurate - ammonium nitrate

    The results of differential thermal analysis of ammonium purpurate-ammonium nitrate system have been presented. The samples have been obtained of melt method. At the contents of ammonium purpurate more than 1 % in samples turn up replacement sequence of ammonium nitrate polymorphic transitions has been established.

    Keywords: ammonium nitrate, ammonium purpurate , phase stable, gas-generating composition

  • Superfine mist collection in the electrostatic precipitator

    The article presents the results of experimental research of the fine mist collection in the electrostatic presipitator.The data confirm the high efficiency of electric cleaning in point of oil mist

    Keywords: gas dust cleaning, electrostatic precipitator, mist collection, collection efficiency, metal-working

  • Sylvinite ore desliming under ultrasonic treatment

    The process of sylvinite ores desliming with ultrasonic treatment is considered. The influence of frequency, intensity and duration of impact to the insoluble rest removal efficiency of sylvinite ores crystals is defined. The optimum mode of sylvinite ores desliming with ultrasonic treatment is established.

    Keywords: desliming, desliming degree, sylvinite ore, ultrasonic treatment, insoluble rest