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Upon irradiation with accelerated electrons of aqueous solutions of copper salts containing methyl alcohol, the formation of a precipitate containing metallic copper and monovalent copper oxide Cu2O is observed in a mass ratio of 75.2 and 24.8%, respectively. The process of metal precipitation and its properties were studied. The radiation–chemical yield of the mass of the precipitated precipitate is (7.2 ± 0.2) × 10–3 g/kGy. The efficiency of the radiation method for the reduction of copper from aqueous solutions of its salts has been substantiated. The method can be promising for the production of precipitates of pure and amorphous metals, as well as for the treatment of water effluents containing toxic transition metals.

When accelerated electrons were irradiated with aqueous solutions of cadmium and lead salts containing methyl alcohol, metal precipitates with densities of 1.17 and 1.1 g/cm3 were obtained and porosities of 86.5 and 90.3%, respectively, and greater surface area. The process of metal deposition was studied and the radiation–chemical yields were calculated, which amounted to (1.7 ± 0.2) × 10–2 and (3.4 ± 0.3) × 10–2 g per 1 kGy for cadmium and lead, respectively, and 1.56 ± 0.05 metal atoms per 100 eV of absorbed radiation energy. The developed method can be promising for obtaining precipitation of pure and amorphous metals from aqueous solutions of their salts, for developing technologies for treating water effluents containing toxic metals, as well as for using porous cadmium and lead in the manufacture of electrical devices.

Radiation stability of MgHPO4‧3H2O magnesium-phosphate ceramic was studied. It was shown that the effect of γ-radiation from 60Co s accompanied by the formation of hydrogen. Oxygen is recorded in trace amounts (less than 1% relative to hydrogen). At a dose of 4–5 MGy, the yield of hydrogen is approximately 0.055 ± 0.005 molecule/100 eV. At larger doses, the accumulation of hydrogen reaches the stationary level. It was found that the “oxidizing component,” hydrogen peroxide, formed in the radiolysis of hydrate water reacts in all probability with magnesium to give magnesium peroxide, MgO2. The irradiation has no noticeable effect on the mechanical strength of the magnesium-phosphate compound.

Ozonolysis is used for oxidation of a model cyclic molecule-decalin, which may be considered as an analog of saturated cyclic molecules present in heavy oil. The conversion of decalin exceeds 50% with the highest yield of formation of acids about 15–17%. Carboxylic acids, ketones/aldehydes, and alcohols are produced as intermediate products. The methods of UV-visible, transmission IR, attenuated total reflection IR-spectroscopy, NMR and mass-spectrometry were used to identify reaction products and unravel a possible reaction mechanism. The key stage of the process is undoubtedly the activation of the first C-H bond and the formation of peroxide radicals.

Cadmium metal is formed in deaerated aqueous solutions of CdSO4 containing СН3ОН on irradiation with accelerated electrons. The yield of the metal is (1.7 ± 0.2) × 10−2 g kGy−1 absorbed dose. The metal precipitation and hydrogen evolution processes were studied as functions of reactant concentrations and absorbed doses, and a scheme of radiation-induced chemical transformations was proposed and substantiated. The method can be promising for the preparation of pure and amorphous transition metal precipitates from aqueous solutions of metal salts and for treatment of waste water containing these toxic metals.

Cementitious materials are widely applied as a matrix for the immobilization of low- and intermediate-level radioactive waste. The use of these materials for high-level waste localization requires knowledge of their properties at high irradiation doses. We have studied the gas evolution and changes in the mechanical strength, composition, and structure of ordinary Portland cement (OPC) upon its irradiation up to absorbed doses of ~ 100 MGy. The decomposition of water present in the cement is accompanied by hydrogen evolution. No oxygen formation was detected. The hydrogen accumulation is described by an exponential equation; the limiting gas concentration reached is approximately 2.8 L per 1 kg of cement. The mechanical strength up to absorbed doses of tens of megagrays varies insignificantly. Irradiation with accelerated (8 MeV) electrons exerts virtually the same effect as does γ-irradiation to the same absorbed dose. The structure, composition, and morphology of cement samples remain virtually unchanged up to high absorbed doses.

The article proposes the construction of a steel-concrete floor. Processes of making, modelling and testing of steel-polystyrene concrete beams and slabs are considered. The results of tests of prototypes are presented. During the tests, the stresses in the steel components of the beams and the deflections value of the plates were measured. The combined action of a thin-walled steel structure and polystyrene concrete is noted. As a result of the combined action of polystyrene concrete and a thin-walled profile, it was possible to more evenly distribute stresses in the metal profile. The destruction of the structure occurred due to the loss of stability of the upper profile belt between the anchoring points. Polystyrene concrete slab is recommended as a roof slab in residential buildings.

Radon indoor build-up poses a serious health threat, increasing the risk of lung cancer in those exposed. Effective limitation of the radon intake from the soil is possible only through the modern building technologies and materials use with high radon-protective characteristics in the building underground part. The ensuring radiation safety complexity is that, depending on the instantaneous soil-atmosphere-building system state, both diffusion and convection can act as the radon intake dominant mechanism, and each of these transfer mechanisms requires its own radon protection measures set. In the article, the dominance areas of each transfer mechanisms are established on the theoretical researches, and an approach to determining the radon load on the building underground shell is proposed.

The kinetics and stoichiometry of catalytic decomposition of hydrazine on 5% Ru/SiO2 in nitric acid solutions were studied. The major reaction products are N2, N2O, and HN3. Ammonium ion is not formed. HN3 is generated owing to the occurrence of a heterogeneous-catalytic redox cycle on the catalyst surface. The influence exerted on the reaction kinetics by reaction mixture composition and temperature was examined. The process scheme was suggested. The hydrazine decomposition on ruthenium catalysts is a structure-sensitive reaction (positive size effect).

This work studies the effect of the porous structure of carbon adsorbent samples obtained using the method of electron-beam processing (EBP) on their physico-chemical properties and sorption properties in respect to Tc(VII). A complex study of the porous structure of the chosen samples was performed. The possibility is shown of developing a thinner porous structure in these carbon materials including micro- and mesopores by means of regulation of radiation exposure combined with treatment by different reagents. It is found that treatment by modifying agents (urea, thiourea, potassium rhodanide) of sorbing materials obtained by radiation processing of the initial plant material enhances their sorption properties in respect to the Tc(VII) anions.

Radiolysis in aqueous nitrate and acetic acid solutions and nitrate/nitric acid and phenol was studied. The radiolysis of these solutes occurs with •NO2 radical, which is the active nitrating agent. Accumulation of nitromethane and nitrite was determined during γ-irradiation of aqueous solutions containing acetic and nitrate solutions. Irradiation of aqueous phenol–nitrate/nitric acid solutions results in the formation of 2- and 4-nitrophenols.

A procedure was developed for preparing an effective sorbent based on lignin phosphorylated in the presence of urea. The phosphorus content was 16.6 wt %. The total exchange capacity was 0.86 mmol g−1 for Cu2+ ions and 0.23 mmol g−1 for UO22+ ions. The effect of urea on the lignin phosphorylation was examined by IR spectroscopy.

Radiation-induced nitration of organic compounds in aqueous solutions was studied. It was found that γ-irradiation of solutions containing acetic and nitric acid and/or their salts gives nitromethane. Dependences of the product yield on the absorbed dose and the contents of components were established. The mechanism of radiation nitration involving radicals is discussed.

The effect of ionizing radiation on cement material was studied over a dose range of up to 2 MGy. Hydrogen is the main gaseous product. Its initial yield is ∼0.8 molecule/100 eV. Incorporation of nitrates into the cement compound leads to an almost complete suppression of hydrogen formation. Simulation results show that the cement is characterized by the process of transfer of ionizing-radiation energy between water and the solid components.

Radiation-chemical transformations of nitrate-acetate aqueous solutions simulating LRW that are disposed of in underground reservoir beds were studied. It was found that the degradation of acetic and nitric acids and their salts is accompanied by formation of nitromethane. The dependences of nitromethane and nitrite accumulation and of nitrate decomposition on the absorbed dose were determined.

A general model for the radiolysis of acetic acid and its aqueous solutions is proposed. The model adequately describes experimental data on the degradation of the acid and the formation of gases (H2, CO2, and CH4) in aqueous solutions at various pH values.

Variations in gas-dynamic characteristics of NTs-16/76-1.44 compressor due to technological deviations and special features of conventional certified (rated) gas-dynamic characteristics of turbocompressors and their stable internal gas-dynamic and specific head characteristics are discussed. An algorithm is recommended for the determination of true characteristics.

A method has been devised for determining the actual gas-dynamic characteristics of a centrifugal compressor (CC). A procedure is given for calculating those characteristics for worn CC by reference to the maker’s panel ones.

We demonstrate that the polytropic efficiency of modern centrifugal compressors can be raised to the level reached by axial-flow compressors. We consider systems of circulation flows around the impeller, the flows past the blading of axial and centrifugal compressors. And we make recommendations for the compressor blade design.

The kinetics and stoichiometry of catalytic decomposition of hydrazine in 0.01 M NaOH solutions in the presence of unstabilized (“gray” colloid) and stabilized with sodium polyacrylate (“brown” colloid) platinum nanoparticles were studied. The main decomposition products are ammonia and N2 with H2 impurity (up to 1.5%), i.e., hydrazine decomposition predominantly follows the stoichiometric equation 3N2H4 = 4NH3 + N2. The catalytic activity was studied as influenced by nanoparticle size distribution. Despite higher nanoparticle dispersion, the catalytic activity of the stabilized “brown” colloid is lower than that of the “gray” colloid. The reaction mechanism is discussed.

A procedure was developed for preparing an effective lignin-based sorbent containing 16.6 wt % phosphorus. The distribution coefficient of uranyl ions with this sorbent is as high as 9680. The physicochemical properties of the sorbent were determined.

The parameters of an observed spectrum of the resonant absorption of γ-quanta in crystals are calculated for single and split lines, with allowance for self-absorption in the source.

170 patients of reproductive age with hyperandrogenemia and infertility were examined. 101 (59.4%) patients became pregnant after the complete therapy of infertility. The examination of patients after non-effective therapy stated that they had had more height stage of androgenemia and remarkable deviation in results of genetic observation in comparison with the same indications of the pregnant women.

The thermophysical and physicomechanical properties of heat-insulation inserts produced from magnesium-silicate materials (dunites) are not inferior to those of inserts produced from quartz sand. The quality of the head metal of the ingots (after the pickup and fins are stripped) depends on the degree of serpentinization of the original rock, i.e., the starting material for the inserts. Among the materials investigated the best indices were those of the dunites of the Kytlym massif (Iovsk body), which proved to be a high-quality raw material for the production of heat insulation inserts. The dunite reserves of the Kytlym deposits will be conclusively established and confirmed in the near future and will be used widely in the metallurgical and machine-construction industries.

Thermal-insulation inserts manufactured on the basis of unfired Iovsk dunite had the same properties as those made from fired Solov'evogorsk dunite and met the requirements of TU 14-8-357-80 with amendments 1 and 2. No burning of the insert was observed and the surface of the head part of the casts was clean and even. The range of the shrinkage defects in the slabs of the experimental and standard casts was virtually identical and was ≤7%. The average value of the leading-edge trim in the case of the experimental and standard casts was virtually identical (9.99 and 10.09%, respectively). The same was also noted for the additional shrinkage segregation and the degree of chemcial nonuniformity at the level of the leading-edge trim.

1. Calculations were made of the constants occurring in semiempirical equations expressing the relation of interatomic distances to theπ -electron charges of bonds in organic compounds. 2. It was shown that in the case of C-C bonds changes inσ -electron charge have relatively little effect on interatomic distances. 3. It was noted that a nitrogen atom can act as a donor of threeπ -electrons.

A dependence was shown to exist between the electronic charges and the lengths of σ -bonds of a saturated carbon atom, which permitted us to explain and to correct the existing data on interatomic distances.

1. Covalent bonds in molecules are formed byσ- andπ-electron charges, which are not in general equal to a whole number of electrons. 2. All bonds attached to atom donors ofπ-electrons haveπ-electron charges. 3. To the approximation, a linear relationship can be assumed betweenπ-electron charge and bond length. 4. A new and very promoting line of work is being developed in the theory of the electronic structure of molecules.

1. A scheme according to which the electronegativities of the halogens were calculated from the dipole moments of halomethanes was substantiated, and a low value of the electronegativity of fluorine, xF= 2.79, was obtained. In particular, the introduction of a high electronegativity of fluorine, xF=3.5, into this scheme does not lead to satisfactory results. 2. The eleetronegativity of fluorine, xF=2.92, was calculated according to data on the dipole moments of fluorosilanes. 3. In a calculation of the electronegativity of fluorine according to thermochemical data, an approximate consideration of the partial double-bonded character of the “single” bond lowers the value of xF to 2.65–2.9. 4. We must reckon not only with the possibility of different electronegativities of fluorine in principle, but also concretely with its low value xF ≈ 2.8.

1. The lengths of C-H bonds in allene and ethylene and of C-C bonds in ethylene were calculated. 2. The π -electron charges of C-C bonds in anthracene, triphenylene, and ovalene were calculated. A comparison was made with Scherr's calculations. 3. It was shown that, when a nitrogen atom forms a bond with an atom-donor ofπ -electrons, the free pair of electrons almost always passes, wholly or partially, into the bond and increases itsπ -electron charge. 4. A table is given of π -electron charges in organic compounds. 5. A discussion is given of various hypotheses which have been advanced for the explanation of the regularities observed in interatomic distances.

1. Simple semiempirical equations are proposed for the relation between force constants and characteristic frequencies of bonds on the one hand and total (σ- + π-) electronic charges of bonds on the other. These equations are checked by calculation of the total electronic charges of ethylene and acetylene. The electronegativity of acetylenic carbon is determined. 2. It is shown that it is possible to calculate π-electronic charges of bonds by two methods which give closely agreeing results-from bond lengths and from electronegativities. 3. An additive scheme is proposed for the calculation of heats of formation of unsaturated hydrocarbons from their elements; the scheme is analogous to that already proposed for saturated hydrocarbons. The separate π-electronic energies of C-C and C-H bonds are calculated. Electronegativities are calculated for carbon atoms in the α- and β -positions with respect to the acetylenic bond of normal 1-alkynes. 4. It is shown that dipole moments of polyatomic molec,,les are generally determined by the nonintegral character of the electronic charges of individual bonds. It is possible to estimate electronegativities of atoms from from dipole moments.

1. It was shown that there is a relation between the thermodynamic (energy) and kinetic factors of chemical reactions, on the one hand, and the electron charges of bonds in the reactant molecules, on the other. Three theses were formulated, and it was shown that from these theses we can derive rules, found earlier by empirical methods, for the direction of organic reactions and also regularities observed in the metallation of hydrocarbons and in certain atomic and free-radical exchange. reactions.It was shown that there is a relation between activation energies and electron charges of bonds. 2. A new qualitative interpretation of the mechanism of the mutual effects of atoms was illustrated by the examples of acetic and chloroacetic acids.In the course of these considerations it was suggested that the directional variation of the electronegativity of an atom is the cause of the trans effect.

1. Theπ-electron distribution hypothesis has been extended to organic compounds containing the CCl, C8r, Cl, Co, Cn, NN and NO bonds. 2. The reliability of the basic data and the final calculated results forπ-electron changes of bonds are discussed.

1. The author proposes to construct an electronic theory of the mutual effects of atoms in organic compounds on the basis of the concept of the electronic charge of a bond, which in the general case is not equal to a whole number of electrons. 2. An equation is proposed which expresses the dependence of electronic charges of bonds on the electronegativities of the atoms. An equation is derived for the calculation of heats of formation of gaseous saturated hydrocarbons from their elements with the aid of values of electronic charges of bonds calculated by the first equation. The agreement found between the experimental values of heats of formation and values calculated with these equations confirms the theoretical postulates on which they were based. In particular, confirmation is found for the postulate that the energies of the σ-bonds are, to the first approximation, directly proportional to their σ-electron charges. A new additive scheme is proposed for the calculation of heats of formation of saturated hydrocarbons. In this scheme the terms of the summation are products of σ-electron charges of bonds and specific electronic energies.

The tissue blood flow of the brain was determined in experiments on rabbits with the aid of xenon-133 after severe burns affecting 20% of the body surface, whole-body x-ray irradiation in a dose of 900 rad, and combined exposure to both factors. The cerebral blood flow was found to be reduced by a lesser degree in burns than the minute volume of the heart (on the average by 20–30% and 50%, respectively). In combined trauma the decrease in the cerebral blood flow was the same as with isolated burns or radiation injury. The authors suggest that a greater decrease in the cerebral blood flow is incompatible with life. The results are evidence of the existence of compensatory mechanisms aimed at maintaining the cerebral blood flow despite a fall in the minute volume of the heart.

The previously proposed explanation for the variation in the lengths ofσ-bonds of organic molecules within the framework of the theory of electronic charges of the bonds is confirmed by the newest data on the interatomic distances and can be used for a quantitative treatment of the Lide effect.