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The article discusses some new energy-efficient metal forming processes (PMD) with complex local loading of the deformation zone for the production of machine parts with a given level of properties. The place of such processes in the aggregate of all OMD technologies is shown, and their classification is given. The initial data of numerical mathematical modeling of the specified class of processes for a particular case are given, the features of the stress-strain state of the metal in the deformation zone are revealed. In the study, from a theoretical point of view, one of the important practical aspects of these technologies is considered: the effect of the value of axial compression on the shape and size of the deformation zone arising from the action of local loading of the workpiece.

Interaction of polyethylenimine with aluminum salts in aqueous solutions was studied; in the process, polymer-colloid complexes exhibiting elevated activity in separation of dispersions with low pH are formed.Interaction of polyethylenimine with aluminum salts in aqueous solutions was studied; in the process, polymer-colloid complexes exhibiting elevated activity in separation of dispersions with low pH are formed.

The activity of polymer-colloid complexes of aluminum polyhydroxochloride and polyacrylamide in separation of model kaolin dispersions and some real dispersions was studied under free and hindered particle sedimentation conditions.

Activities of succinate dehydrogenase (SDH) and α-glycerophosphate dehydrogenase (hyaloplasmic and mitochondrial: α-GPDHHand α-GPDHM) in peripheral blood lymphocytes, and the response of SDH activity to exogenous epinephrine in vitro(the epinephrine test) were studied in 20 healthy subjects and 46 patients with hypertensive neurocirculatory dystonia. Activities of SDH, α-GPDHH, and α-GPDHM in blood lymphocytes and SDH adrenoreactivity in epinephrine test were higher in patients than in healthy controls. Treatment with hypotensive agents (isradipin and pyrroxan) moderated adrenoreactivity. Phytotherapy normalized the baseline activities of succinate oxidase system and α-glycerophosphate pathway in blood lymphocytes.

Gelation in concentrated solutions of high-basicity aluminum hydroxychloride in the presence of inorganic salts was studied. Comparative evaluation of the coagulation activities of aluminum hydroxychloride and solid formulations on its base in water purification was made.

Heat-insulating ceramic materials have been developed, whose porous structure is provided by foaming and gas formation. Foaming and gas-forming agents, stabilizing, plastifying, and other additives and fixing agents for foam and gas mixtures are identified.

We propose a method for the analysis of stable crack-length increment Δa(where Δais regarded as a function depending on the parameters KIand σrof the two-criterion approach). It is shown that the KRcurve consists of two portions: {K′}Rand {K′ ′}Rcurves, which in the framework of the fracture evaluation diagram correspond to two portions of the loading curve – prior to and after its intersection with the limit curve of the fracture evaluation diagram. We propose an analytic description of the {K′}Rcurve as the first approximation, while the shape of the {K′ ′}Rcurve is shown to be fully determined by the limit curve of the fracture evaluation diagram. The method has been verified by using the experimental data of the ASTM Round Robin tests performed in 1979–1980 and predicting the maximum fracture load Pfof cracked specimens made of various materials: compact specimens, center-cracked specimens and special specimens with three holes. Good agreement between predicted and experimental data is demonstrated.

The structured composite can involve the porous materials providing the important internal damping that is usable in mechanical engineering applications. The stiff base material is equipped by layer/s of softer porous material/s covered by constrained layer. Such layered structure is characterized by increased internal damping in vibration process. Paper analyses some either measured or simulated mechanical properties of designed layered porous composites. Novelty provided in paper is a specific application of structured composite for damping the high frequency vibrations in resonance frequency obtaining the beneficial results, e.g. 40-48% of maximum amplitude reduction.

The current time is characterized by the rapid development of modern production methods. These modern production methods are in many cases closely linked to progressive production methods, including EDM. The required high productivity and product quality is the reason for using such production methods. In addition to flawless production processes and highly sophisticated production equipment, these requirements can only be met using high-quality production tools. This paper, therefore, aims to describe the results of the analysis of current approaches in the field of modern trends in the development of electrical discharge machining, closely focusing on the development of control systems for generating electrical impulses in connection with the development of advanced tool electrodes. The performed analysis is also supplemented by the definition of mutual relations between selected properties of wire tool electrodes, their cutting power, and the achieved quality of the machined surface after electrical discharge machining. This should significantly help in increasing the quality level of the machined surface during wire electrical discharge machining and at the same time higher productivity of the electroerosive process. This will make this technology more competitive compared to other advanced technologies.

Abstract: Heat exchange of dynamic (mixing) beds of powders with heat-transfer surfaces in a tube with a helical conveyer and in a rotating smooth horizontal cylinder is studied by experimental methods. The heat-transfer coefficients as functions of the regime of powder motion are obtained.

The newly devised model makes it possible to determine the heat treatment regimes of alloys of the system Cu-Al-Mn with similar temperature manifestations of ESM, with the attainment of the maximal thermomechanical characteristics possible for each group of alloys. As a result of heat treatment in the optimal regimes, ternary intermetallic compounds segregate in the structure of these alloys, and they improve the parameters of the ESM. Consequently, for widespread use in engineering we recommend alloys of the system Cu-Al-Mn which are distinguished from the known alloys with the ESM (based on titanium nickelide) by the accessibility of the initial materials and simpler production technology.

Without Abstract:

Summary This article discusses methods for providing a reliable forecast of the gas-dynamic behaviour of coal seams and adjacent strata. It shows that the ash content of carbonaceous materials determines their sorptive capacity (a universally applicable expression is presented for calculating the methane content of a sample) whilst the rate of methane desorption is a function of the degree of geological disturbance, i.e. the number and distribution of the macropores and fractures in the sample. This effect becomes less important as the sample ash content increases and effectively disappears above a certain value for high permeability materials.

1.Carboxyl derivatives of adamantane react with either 1,1-dichloroethylene or CO in a H2SO4-HNO3 medium to give the corresponding dicarboxylic acids.2.The nitric acid concentration in the reaction mixture exerts an important effect on the yield of these acids.

Via direct oxidative addition of 1,1-dichloroethylene to adamantane or 1,3-dimethyladamantane one obtains diethanoic acids of the adamantane series, which are useful in themselves or for preparation of other functional derivatives. Optimal reaction conditions were found by mathematical modeling.

1.The introduction of the adamantyl radical to the molecule of methacrylates and vinyl esters of carboxylic acids leads to an increase in their polymerizability.2.With increase in the distance of adamantyl radical from the double bond of the monomer, the polymerizability of the latter decreases.

The optimum conditions were found for obtaining the polyester from the acid chloride of 1,3-adamantanedicarboxylic acid and phenolphthalein.

1.The selective spin-lattice relaxation times T1 for the carbon nuclei of poly[vinyl-(1-adamantyl)carboxylate] were measured in tetrachloroethylene and the correlation time for internal rotation of the adamantyl group was evaluated.2.The nature of the intramolecular interactions in this compound was examined.

a-Picolyllithium and 2,6-lutidyllithium add to alkylthiovinylacetylenes to form adducts which, after demetallation with water, form allenic thioethers of the pyridine series.

Summary In the manufacture of lightweight by the semidry pressing method using thermoanthracite as the combustible addition, it is possible to obtain goods corresponding to GOST 5040-58. The firing time is 144 h. The firing should be carried out in an oxidizing atmosphere with a ten-course setting in separate chambers with a special schedule. It is necessary to carry out further work to find whether it is possible to reduce the firing time in the low-temperature interval by selecting the appropriate draft schedule.

The aminomethyl(aminoethyl)adamantane hydrochlorides (V) are prepared from the acids (I) via the intermediates (II) ‐ (IV).

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