Mathematical Description of the Kinetics of the Macromolecular Reaction of Oxirane Groups of Polycaproamide—Polyglycidyl Methacrylate Copolymer with Diamines

The formation of amino derivatives of PCA—PGMA graft copolymers is established by chemical analysis and IR spectroscopy in their reaction with ethylenediamine and hexamethylenediamine. Mathematical processing of the experimental data using a modified quasistationary method allowed describing the kinetics of amination of PCA—PGMA graft copolymers. The proposed approach can be used for controlling heterogeneous processes in polymer systems.     

The Concept of Chamber Design for Explosive Thermonuclear Fusion Energetics

The possibility of realizing the solution of mankind's energy problem by the explosive thermonuclear fusion method that was proposed by Academician A. D. Sakharov is assessed. The essence of the method consists of the use of the energy of low–power thermonuclear explosions performed cyclically in stationary explosion–proof chambers equipped with a means for selection and utilization of the thermal energy of the explosion. Here the basic problem is to design airtight chambers capable of withstanding multiple thermonuclear explosions whose power is equal to 10—25 ktons of TNT. The available data on this problem are examined. The concept of designingreliable explosion–proof chambers for the solution of the indicated problem is formulated.     

Organization of contemporary systems for transport-warehouse servicing in the manufacture of man-made fibres

Conclusions -- It is necessary to begin the development of contemporary transport—warehouse systems promptly. Delay in development threatens in the future large losses and potential possibilities for new technological equipment.-- Work should be carried out in two directions: development of a complex of automated equipment for transport—warehouse systems; and performing investigative work on developing a complex of program—technical media and a mathematical—statistical model of transport—servicing systems.Translated from Khimicheskie Volokna, No. 5, pp. 50–51, September–October, 1990.     

Mathematical Description of the Electrostatic State of Chemical Fibres with Consideration of the Forms of Intermolecular and Interfibre Interactions

A method for determining the electrostatic state of chemical fibres is developed. Mathematical dependences that allow determining the electrical capacitance of chemical fibres with different structural features and packages with longitudinal and transverse arrangement of the fibres are obtained. The inverse problem — finding the functional dependence of the dielectric constant of the investigated material on the initial capacitance — is solved.__________Translated from Khimicheskie Volokna, No. 1, pp. 56–58, January–February, 2005.     

Polarization-interference micromethod for the study of mutual diffusion in polymer systems

Summary A polarization-interference technique is developed for the study of mutual diffusion that is applicable to systems covering the whole concentration range from polymer — low-molecular-weight compound systems to polymer — oligomer systems. The technique is based on variations of the refraction index within the diffusion zone and is shown to have advantages over similar ones. Its accuracy in terms of wavelength is 0.04. The polybutadiene — dioctyl phtalate system is used to illustrate how the concentration distribution of the components is calculated.     

Powdered Polymer Paints Used as Protective Lubricants in the Production of Refractories,Construction Bricks,and Ceramic Components

A new technique for coating the frames of drying cars using polymer powdered paints rather than the conventional minium is proposed. The advantages of this method — extended service life of the frames, reduced rejection rate of substandard product, increased utilization of post-service frames — have provided a savings of 1,816,620 roubles/year, allowing for the costs of purchase and installation of the processing line. Polymer powdered paints can be used in the production of refractories, construction bricks, and ceramic components as an efficient protective coating for the frames of drying cars.     

Effect of the monomer ratio and initiating system on the disperse composition of polyacrylonitrile copolymers

Conclusions The mean size and polydispersity of polymer particles are increased on increasing the MMA/(AN, NaVS) ratio, as a function of the initiating systems used, in the following order: ammonium persulfate—rongalite, persulfate—bisulfite, and persulfate—metabisulfite.The PAN copolymer suspensions obtained under laboratory and under pilot plant conditions have identical mean particle sizes, but have a different disperse composition of the polymer particles.There is a slight dependence of the filterability resistance of polymer suspensions on the MMA/(AN, NaVS) ratio and on the initiating system used, which exerts no effect on the technological centrifuging regime.Of the investigated redox initiating systems, the most appropriae one for the manufacture of a PAN copolymer with an elevated MMA content is the ammonium persulfate—sodium bisulfite system.Bulgaria. Translated from Khimicheskie Volokna, No. 4, pp. 45–47, July–August, 1985.     

Dynamics of Heating of Fluoride Stock in Manufacture of Optical Fibres

Heating of fluoride stock was analyzed. A module for drawing fluoride stock into optical fibres was developed. The transient responses and transmitting functions of the object of control in “current strength—temperature” and “gas flow—temperature” channels were obtained. The structure of a system for controlling heating of fluoride stock was proposed based on the results of the study.__________Translated from Khimicheskie Volokna, No. 2, pp. 16–18, March–April, 2005.     

Quantitative Determination of the Limits of Hydrodynamic Modes of Flotation in Rheologically Complex Media

The introduction of a new parameter—the modified Stokes number—is proposed and substantiated. This parameter quantitatively determines the limits of the modes of inertial and inertialess flotation in rheologically complex media with non-Newtonian viscosity.__________Translated from Teoreticheskie Osnovy Khimicheskoi Tekhnologii, Vol. 39, No. 3, 2005, pp. 349–351.Original Russian Text Copyright © 2005 by Sokovnin, Zagoskina.     

Improvement of Dyeing Technologies for Polyester Textiles

The effect of inorganic salts on the melting point and viscosity of a carbamide melt and its solvating power with respect to disperse dyes and polyester fibre was investigated. The high effectiveness of the carbamide—LiCl and carbamide—CaCl systems in fixation of disperse dyes on polyester fibre was established. A probable mechanism is proposed for the activating effect of inorganic salts on fixation of disperse anthraquinone dyes on polyester fibre in the presence of carbamide.     

Melting of binary mixtures of low-density polyethylene and alkylbenzenes

Regardless of the dependence on the thermal history and structure of the alkylbenzene the melting point of the LDPE—alkylbenzene binary system is a linear function of the composition for a concentration of the lowmolecular-weight component of up to 0.9–0.95 mass fraction. Annealing of LDPE — alkylbenzene binary systems at temperatures below their melting point leads to differentiation of solvents with respect to the level of thermodynamic affinity. The heat of fusion of LDPE crystals is 293±15 J/g.Ivanovo State Academy of Chemical Engineering. Institute of Chemistry of Nonaqueous Solutions, Russian Academy of Sciences. Translated from Khimicheskie Volokna, No. 4, pp. 18–21, July–August, 1996.     

Rheological properties of highly filled,protein-containing spinning compositions

The dependences of _rel of spinning compositions for fabrication of fibre biocatalysts (FBC) — disperse systems based on solutions of cellulose triacetate (CTA) in methylene chloride (MC) of different concentration — on the volume fraction of disperse phase (solution of enzyme or modified enzyme) in a wide range were examined. The effect of the viscosity of the dispersion medium on the _cr where phase inversion of the emulsion takes place was established for these systems. Based on an analysis of the rheological curves of solutions of -galactosidase modified in different conditions, it was found that one cause of the increase in the viscosity of spinning compositions in enzyme modification is a change in the elasticity of the particles of disperse phase. Based on the results of studying the rheological properties of solutions of CTA in MC of different composition and spinning compositions based on them, a method was proposed for obtaining a highly active and stable FBC.Translated from Khimicheskie Volokna, No. 5, pp. 21–26, September–October, 1995.     

Autoadhesive Bonding of Modified Polyester Fibres

An efficient method of autoadhesive bonding of polyester fibres in a high-strength nonwoven textile was developed. The method includes application of a small amount (0.25 wt. %) of a new organosilicon modifier — oligo(ethoxy)(isobutoxy)siloxane — on washed fibres and pressing under a pressure of 2 MPa for 2 min. The method allows reducing the pressing temperature by 5-6°C and elimiantes the use of 30-40 wt. % traditional bonding substances.     

Physicochemical basis of the sol-gel process giving selective layers of ultrafiltration ceramic membranes from zirconia hydrosol

Selective layers of ceramic ultrafiltration membranes were prepared by the sol-gel method using zirconia hydrosol as the initial material. On the basis of turbidimetric investigations, a compatibility diagram was constructed in the zirconia (sol) — polymer thickener — water system. The results of x-ray phase analysis and thermogravimetric analysis were used to choose the regime for heat treatment of the sol — polymer thickener compositions in order to prepare selective layers. The characteristics of the pore structure of the selective layers meet the requirements imposed on ultrafiltration membranes.     

Manufacture of Granulated Chitosan

Conditions for dry-wet spinning of spherical chitosan granules 0.5–2.0 mm in diameter into a two-layer spinning bath consisting of immiscible liquids are proposed, where an organic liquid, decane in particular, is the upper layer of the bath while a solution of ammonium hydroxide is the lower layer. The possibility of obtaining chitosan microgranules from 2 to 30 µm in diameter by emulsification of a solution of chitosan in decane or a solution of an anion-active surfactant — sodium dodecyl sulfate — is demonstrated. The effect of the molecular weight and concentration of the solutions on the granule-forming power of chitosan is established. A 6% solution of chitosan with a molecular weight of 200 kD is recommended for further studies.__________Translated from Khimicheskie Volokna, No. 5, pp. 26–29, January–February, 2005.     

Alkane oxidation by an iron complex-hydrogen peroxide system in acetonitrile. The model of methanemonooxygenase

The oxidation of methane and other light alkanes in the system iron complex — hydrogen peroxide has been studied. The efficiency of this system of alkane oxidation depends on water concentration. The catalytic methanol formation from methane with respect to the binuclear iron complex has been observed. The role of iron-oxocomplexes in oxidation of alkanes by methanemonooxygenase and model systems is discussed.Presented in part at the Royal Society — Soviet Academy Workshop on Catalysis, Oxford, April 1989.     

A method of calculation of a guniting flame

Conclusions A physicomathematical model and a method of calculation of the guniting flame making it possible to calculate the basic characteristics of flame guniting — combustion of the fuel and heating of the refractory — have been developed.An example is given of calculation of the guniting flame with parameters characteristic of industrial equipment. Based on its results the processes occurring in the guniting flame are described qualitatively.Translated from Ogneupory, No. 6, pp. 46–49, June, 1986.     

Transfer processes in heterogeneous reduction reactors

The results of experimental study are presented and mathematical models are proposed for heat and mass-transfer coefficients in a packed bed layer of reacting particles immersed in a liquid through which the reaction products are bubbled. It is shown that turbulence models based on taking into account the motion of bubbles, which rise under the action of buoyancy forces and set the liquid in swirling motion, quite adequately describe the transfer processes in gas—liquid systems, including the layer of dispersed particles.Translated from Teoreticheskie Osnovy Khimicheskoi Tekhnologii, Vol. 38, No. 6, 2004, pp. 611–615.Original Russian Text Copyright © 2004 by S. Panchenko, D. Panchenko, Glebova.     

A study of the thermodynamics of precipitation of a polyheteroarylene using low-molecular models

Conclusions On the basis of colloid-chemical, thermodynamic, and spectral studies of the process of precipitation of PBITA and its low-molecular analogs, models have been constructed of the solvation phenomena in precipitation of PBITA.Types of complexes and their behavior in polymer (or model)—solvent—electrolyte systems in the presence of a precipitant have been examined.It has been found that the benzamide unit is responsible for the precipitation of the models and of PBITA.Values of the thermodynamic characteristics of precipitation of the models have been discussed; these additionally support an effect of precipitation mixture composition on precipitate morphology.Translated from Khimicheskie Volokna, No. 2, pp. 18–21, March–April, 1986.     

Production and properties of highly porous zircon materials

Conclusions We proposed, using zircon as an example, the principle of forming pores of two types — cellular and capillary — for obtaining highly porous (up to 90%) ceramics. It consists of a combination of the foam method and the introduction of removeable foamed polystyrene. At the stage of forming and drying the system is distinguished by a high volume constancy, uniformity of properties, and the possibility of carrying out rapid drying.On the basis of a zircon suspension as the bond and crushed zircon foamed ceramics as the filler we obtained a highly porous ceramic concrete with a porosity of 50–70% and a compressive strength of 12–24 MPa.A marked influence on the properties of the resulting materials is exerted by the microcracks formed as a result of the removal of the expanded polystyrene (PPS) in the foamed ceramic, and the presence of uncompensated shrinkage in the ceramic concrete. With an increase in the value of the uncompensated shrinkage from 0 to 7%, the thermal-shock resistance of the ceramic concretes is increased 1.3 times and the thermal conductivity is reduced by a factor of 1.25.Translated from Ogneupory, No. 7, pp. 20–25, July, 1984.