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The article covers a system of self-adaptable automatic adjustment for elastically deformable packing blocks in mass-exchange apparatuses based on the identification of inertial component peaks in the structure of the filtration flow through the layers of elastically deformable packing materials. It shows the possibilities for the use of wastes from metal-building enterprises formed during machine processing of stainless alloyed steels as packing materials in elastically deformable blocks of mass-exchange apparatuses. The article also describes the automatic control system for hydraulic and mechanic modes by means of stepwise volumetric deformation of the blocks with packing materials.

The paper presents the scheme and algorithm of automatic adjustment of process parameters for elastically deformed blocks of packing materials in mass exchange apparatuses by the turbulization index that indicates fluid dynamics bursts of the inertial compound in the structure of the filtration flow and is an instrument for automatic adjustment of flow dynamic modes of developed turbulization and emulsification in elastically deformed packing blocks at the commissioning stage. The article describes main features and prospects of use of industrial wastes from metal-working plants as packing materials in elastically deformable contact blocks in mass exchanges apparatuses.

A modified system for automatic control of hydrodynamic operating modes of packed adsorption columns for the selective cleaning of gas emissions is described, which allows automatic adjustment of the operating modes of packed mass transfer apparatus. Presents the scheme and algorithm of developed system with the automatic adjustment (calibration) mode of main operating parameters. The main features and advantages of using elastically deformable blocks of packed material are given on the example of metal chips, i.e. waste of machine tools as a packed material that meet all requirements of the ongoing mass transfer processes and are amenable to automated regulation. The developed system of automatic regulation of parameters of packed units, but also to solve a very serious environmental problem of industrial waste recovery. A classification technique of studying the hydrodynamics of packed materials, capable of concluding the suitability of this sample of packing material for a specific mass transfer process, in particular the adsorption process for the selective cleaning of gas emissions.

The article presents the results of the experiments on fluid and gas dynamics through a layer of packing material S-Aisi304ε-0, 95 (ε=0, 95, σ=160m2/m3) suggested for use as packing blocks in small-size evaporation cooling apparatuses for industrial recirculated water. Experimentally confirmed effects are covered that prove the performance efficiency of wastes from metal-working machinery as packing materials for contact evaporation blocks. Results of mathematical modelling and engineering calculation of the main process parameters and dimensions for a small-size evaporation cooling apparatus for industrial recirculated water with use of contact blocks filled with the studied packing material are provided.

The authors have studied the use of wastes from metalworking machines for packings of heat-and-mass exchange apparatuses as well as the adjustment of their basic parameters and flow modes. The articles show the photograph and schematic view of the experimental plant for studying a wide range of properties of heat-and-mass exchange packing devices and cartridges with the studied adjustable packing material that was represented by metal stainless steel shavings are given. A method is offered to process experimental data which helps to classify the packing material by mass exchange processes; the article describes the calculation algorithm for a small-sized industrial cooling tower used for cooling circulating water with a compacted package of metal shavings as a packing. Initially, reference, calculation geometric and technological parameters of the designed small-sized ventilator cooling tower with compressed metal shavings package used as packing material and schematic view of adjustable packing block were introduced.

The article presents an approach to centralised collection, recycling and removal of waste pickling and galvanic solutions and sludge designed for small steel making plants and workshops having the described processes and using flow-through filter blocks.

The article describes a new promising heat and mass exchange packing for evaporation cooling maintaining an intensive dripping flow mode and providing for disinfection of circulation water in electric field. The article includes the schematic diagram of the designed packing and a sample calculation of an industrial apparatus for evaporation cooling applying the designed heat and mass exchange packing. The authors describe the principle for preservation of surface properties of the packing elements. A method is offered to process experimental data, which helps to classify the packing material of various configurations, by mass exchange processes. The article also covers the calculation algorithm for key geometric and technological parameters of evaporation cooling apparatuses ensuring intensive dripping and film-dripping flow modes. Initial, reference and calculation parameters of the designed evaporation cooling apparatus with heat and mass exchange packing ensuring an intensive dripping flow mode and providing for disinfection of circulation water was introduced.

The paper provides a scheme of the designed sectioned mass exchange packing, a description of an experimental plant for studying flow dynamics and heat and mass exchange processes in packing devices, and experimental results of investigation on flow characteristics of the designed sectioned mass exchange packing. The authors describe the advantages and structural aspects of the use of new adjustable packing materials. The authors have studied the use of wastes from metal working machines for packings of heat-and-mass exchange apparatuses as well as the adjustment (self-adjustment) of their basic parameters and flow modes. The article also covers the classifying method for processing of experimental data that helps to perform an express investigation and provide conclusions on the applicability of packing materials for different mass exchange processes. Besides, the authors provide the results of calculation of main process parameters and dimensions of an industrial absorber equipped with a sectioned mass exchange packing each section in which is to be adjusted and managed by flow modes.

The article represents the system for automated process parameters adjustment of packed mass exchange apparatuses intended for selective gas emissions treatment. It describes the flow chart and algorithm of adjustment program of the packed mass exchange apparatus. It also outlines the identification technique for required (optimal) flow dynamic operating modes of the mass exchange packed absorbers. The data obtained through automated adjustment of process parameters serve (are needed) for functioning of the self-adaptable automated mode control system of industrial absorbers for selective gas emissions treatment.

The paper provides the scheme and algorithm of the automatic system controlling the operation modes of evaporation cooling apparatuses for industrial recirculating water of local recirculating water supply systems. The authors have described the principle of parameter registration and the automatic calibration of the main parameters at the commissioning stage and during the operation of heat and mass transfer technological equipment. The authors have developed a new approach to the use of elastically deformable heat and mass transfer packing blocks and wastes from metalworking machines as packing contact devices for evaporation cooling apparatuses. Compressed blocks of metal shavings can be volumetrically elastically deformed which allows adjusting operation modes automatically and solving partly a very serious problem of disposing industrial wastes from machine-building enterprises. The article also covers developing of evaporation cooling apparatuses.

The article dwells on the method for summarizing experimental data on hydrodynamics of one-phase filtration flows through packed heat-and-mass exchange apparatuses differing in configuration. Summarizing is performed using a modified generalized equation. The described method simplifies the work with experimental bulk data, helps to compare the packed heat-and-mass exchange apparatuses, assess their energy performance and find the ways for their industrial implementation in heat-and mass exchange equipment.

Data of experimental study of hydrodynamics, heat and mass transfer of packing with adjustable parameters and some comparative characteristics of the packed device with packing, which have wide industrial application, are given in the article.

The paper provides a description of the developed experimental plant for studying hydrodynamic and heat and mass exchange processes in packing devices of all kinds of configuration, examples of the obtained data and original classification methods for processing experimental data. The authors describe hydrodynamic characteristics allowing carrying out classification studies and obtaining the necessary data to complete the developed methods for calculating mass exchange devices: the retaining capacity of packing devices at liquid and gas phases in particular. The authors provide the criteria function X=f(Rem) which gives a direction for industrial application of packing contact devises. The function is based on the analysis and generalization of the experimental data obtained in express studies of single-phase filtration curves. The paper also covers an example of the experimental data of the response function in case of recognizing flow structures of contact phases which allow obtaining necessary data to complete the developed diffusion models of mass exchange processes and implement calculations of mass exchange packing with a high precision.

Data of experimental study of hydrodynamics, heat and mass transfer of cascade bowl-type heat and mass exchange packing with dripping spray mode and some comparative characteristics of the packed device with packing, which have wide industrial application, are given in the article.

The paper covers the prospects to use industrial wastes from machine-building enterprises, appearing while machining various steel grades, as packing materials for industrial absorbers for environmental cleaning processes of gas emissions. The article provides obtained and processed in the criterial way experimental data in hydrodynamics of a packing material sample from metal working machines wastes appearing while treating Aisi 316Ti steel bars; packing material according to the classification method for processing experimental data λ=f(Rem) is oriented to the absorption process during selective gas cleaning in environmental equipment. The authors have compared the studied packing material to the packing that are widely used in industries. The authors have studied the main experimentally confirmed hydrodynamic effects indicating the high efficiency of the proposed packing material. The authors have made calculations for a small-sized industrial absorber for cleaning gas emissions with the use of the studied packing material.

The impurity composition on and near the cylindrical surface of a CVD polycrystalline tungsten film covering Nb + 1% Zr alloy is determined with SIMS and AES methods. The alloy is used as the collector material in thermionic thermal-to-electrical energy converters of space-borne nuclear power plants. A comparison with the impurity composition of a reference plane-parallel relatively perfect W(110) single crystal is made. At all stages of milling the surface by He+ and Ar+ ion beams, the coating is contaminated greater than the reference. Even after the first heating in vacuo to 1625 K, all the impurities, except carbon, oxygen, and niobium, are removed. The three impurities named are not removed by heating up to 2075 K. Niobium is shown to diffuse toward the surface through a W coating of thickness up to 30 µm. At temperatures above 1925 K, the material is heavily sputtered. After 50 oxidation cycles, the carbon content in the coating is greatly reduced. However, the subsequent 25 cycles fail in further decreasing the carbon content. The fact that oxygen cannot be removed from the surface by heating to 1925–2075 K suggests the presence of high-temperature surface Nb2W2O suboxide. It is recommended that the purity of the W coating raised in order to improve its adhesion to the O-Cs film.

Secondary-ion mass spectrometry (SIMS), Auger electron spectroscopy (AES), and low-energy electron diffraction (LEED) methods are used to determine the chemical composition on the surface and in the near-surface layer of CVD cylindrical single-crystal tungsten, which is applied as the emitter material in thermionic thermal-to-electrical energy converters in space-borne nuclear power plants. Results obtained are compared with those for reference perfect plane-parallel W(110).

A technology for manufacturing zirconia-based materials of various quality grade intended for production of ceramic and refractory components is developed.

Experience gathered in recording neutrons with the aid of polymer track detectors on calibrated neutron sources and around the 70 GeV proton synchrotron has shown that detectors making use of fissile nuclides in combination with polyethylene terephthalate track detectors and spark counting of the tracks are suitable and promising for their large scale use as measuring means of dosimetric characteristics of the neutron fields in a high-energy accelerator. They can be used to build an albedo-track dosimeter in which235U is the albedo detector and237Np,238U, and232Th are used as the threshold detector. Also a nitrate cellulose film without a converter can be used as a threshold detector but there the measurement error is 2–3 times greater than in the detectors making use of fissile nuclides because the film sensitivity has a considerable (∿30%) spread even to monochromatic neutrons. In addition, a detector based on209Bi can be used for spectrometric measurements of high-energy neutron spectra.

Consideration is given to the question of how the displacement of the 4S shells of the Fe3+ ion with respect to the nucleus accompanying the temperature oscillations of atoms in a crystal affects the temperature dependence of the isomeric shift of the Mossbauer spectrum.

1. The difference in the structure of steel through the depth induced by incomplete hardenability of large rotors has a strong effect on the resistance to crack propagationap and ductile-brittle temperature T50, but has a negligible effect on the work of crack initiation and the standard mechanical properties. 2. To determine the resistance to fracture of large parts it is expedient to use samples with lateral notches.

1. The character of the γ→α transformation along the height and through the cross section of the 70-ton ingot of steel 34KhN1MAR was investigated by means of high-temperature metallography. 2. The γ→α transformation temperatures were determined in dendritic sections of various structural zones of the ingot. 3. A relationship was established between the degree of dendritic segregation and the temperature range of the γ→α transformation.

During rotation of the mixing device, the dispersed medium, under the action of centrifugal force, flows around it, taking on a directed motion along the device. The energy introduced into the dispersed medium is given up to the medium in the immediate proximity of the surface of the mixing device. In view of the great peripheral velocities of the mixing device, around it there arise considerable velocity gradients of the dispersed medium, which leads to the appearance of high shear stresses. In addition, the ~flow around the mixing device sucks out the dispersion medium located on the convex side of the working elements, setting up intense axial shear. Rotary-jet mixing devices, used as the working elements of bead mills, can be mounted on the shaft with the convex part downward or with the convex part upward, or in a combined manner (in the latter case, they can be either of identical or different diameters). On the basis of preliminary experiments, it has been established that the use of rotaryjet mixing devices makes it possible to vary over wide limits the ratio of the axial and tangential components of the force acting on a bead at the wall of the mill. As is well known [3], the correct choice of this ratio determines the most favorable conditions for collisions between the grinding bodies and the particles of the substance being dispersed. In view of this, there has arisen a need to investigate the above-mentioned devices to determine their optimal dimensions, arrangement on the shaft, and the efficiency of their use for dispersion processes in bead mills. With a study of the structure of the flow of the dispersed medium in a mill with different means of attachment of the working elements under study, it was established that microvertexes are observed to the greatest degree with a combination installation of the working elements. For a visual study of the structure of the fflow in a dispersed medium (iron oxide), tracers were introduced, i.e=, lumps of mica measuring 2  4  I mm. With illumination of the container by a slit source of light, a flat beam of light, passing through the container, is partially reflected from particles of mica moving along with the dispersed medium. Figure 2 gives the results of an investigation of the degree of grinding, characterized by the content of particles less than 2.5 ~m, on the ratio of the diameters d~/d of the working elements with their combination arrangement and on the ratio of the diameter d of the working element to the diameter D of the container. The investigated models of the working elements had a diameter d = 60, 80, I00, and 110 ram, and the container a diameter D = 120 ram. As can be seen, the optimal ratio of the ratio of the diameters of the working elements dl/ d = 0.8. With an increase in the diameter d of the working element, the degree of grinding rises and attains a maximum, irregardless of the means used for attachment of the working elements with d

The use of noncontact, low-inertia elements (semiconducting transistors) has enabled us to create a bridge circuit with a very low balancing time. Measurements may be made in 20 msec by using the apparatus described.