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The structural and phase changes in the surface layer of the 1933 aluminum alloy caused by the irradiation of a high-current relativistic electron beam are studied. The impact of the electron beam leads to the formation of a remelted surface layer with surface relief and microcracks. The structural phase state of this layer is determined by the complex impact of the electron beam and the kinetics of melt crystallization under ultrafast cooling. Via X-ray diffraction studies and the results of energy dispersive X-ray microanalysis it became possible to make a conclusion that submicron sizes of magnesium oxide are present in the remelted layer. MgO inclusions are distributed homogeneously in the remelted layer. The presence of MgO inclusions leads to hardening of the surface layer of the alloy. The nature of formation of MgO during the impact of a pulsed electron beam are discussed

The aim of the study was a comparative assessment of radiation doses to the population of the Voronezh and Irkutsk regions according to the unified state system for monitoring individual doses and radiation-hygienic certification. The objects of research were the territories of the Voronezh and Irkutsk regions, significantly differing in climatic conditions and resources, industrial potential, but comparable in terms of population. The subject of the study was the average territorial values of radiation doses to personnel due to the normal operation of anthropogenic sources, radiation doses to the population due to natural sources and anthropogenic background, radiation doses to patients due to the use of ionizing radiation in medical diagnostics. The method of comparative analysis of effective collective and individual average annual radiation doses was used. In the Voronezh and Irkutsk regions, the priority dose-generating factor is natural radiation, which contribution to the annual effective collective dose is 83.33 and 89.18%, respectively. At the same time, the average individual annual effective doses to the population due to natural sources of ionizing radiation in the Irkutsk region in relation to the Voronezh region are significantly higher for radon – 2,81 times, due to the content of radionuclides in drinking water – 1,93 times and external terrigenous radiation – 1,46 times, which leads to a two-fold difference in the total individual effective doses associated with natural sources of ionizing radiation. These differences are explained by the features of the physical and geographical location of territories. There are significant differences in the values of the average effective annual doses of the population due to global fallouts and past radiation accidents, because a part of the territory of the Voronezh region was exposed to radioactive contamination as a result of the accident at the Chernobyl nuclear power plant (in the Voronezh region – 0.062 mSv / year, in the Irkutsk -0.005 mSv / year). Radiography (63.15 and 67.27%) makes the leading contribution to the value of medical radiation doses, which occupy the second place in the structures of the effective collective annual doses to the population (in the Voronezh region make up 16.46%, in the Irkutsk region – 10.74%) and fluorography (31.29 and 27.41% in the regions, respectively). It was established that the radiation situation in the Voronezh and Irkutsk regions remains stable and safe.

Recent numerical calculation of the coefficients of diffusion of radiation point defects in hexagonal crystals have shown that the main assumption of the theory of radiation growth of zirconium—namely, the assumption about diffusional anisotropy difference (DAD)—is not fulfilled. Thus, the elastic ideology based on the concept of bias of sinks, i.e., elastic interaction difference (EID), remains relevant. In this connection, bias for the basal edge loop of zirconium in a toroidal reservoir is numerically calculated by the finite difference method under consideration of the elastic anisotropy of a hexagonal crystal. The toroidal geometry of the reservoir allows one to perform calculations for a loop with any size and without any correction for the elastic field in the region, in which it has an effect. The dependences of the bias of the loop on its radius and nature are obtained for various drain densities. The essential role of the shape of the boundary condition on the external surface of the reservoir is shown. Prospects for further research in constructing the theory of radiation growth of zirconium on the basis of elastic ideology are outlined.

The structural and phase changes in the surface layer of an aluminum alloy 1933 caused by the action of a relativistic pulsed electron beam are studied. The structural and phase state of this layer is determined by the impact action of the electron beam and by the kinetics of crystallization from the melt under ultrafast cooling. The impact of a pulsed electron beam is accompanied by the formation of a developed surface relief and the appearance of microcracks on it. The structure of the modified layer is nonequilibrium. X-ray diffraction studies and the results of energy dispersive X-ray microanalysis made it possible to determine that magnesium oxide inclusions are present in the remelted layer. MgO inclusions are generally uniformly distributed in the remelted layer. The maximum size of MgO inclusions does not exceed 1 μm. The causes and mechanisms of the formation of magnesium oxide during the action of a pulsed electron beam are discussed.

The paper discusses the problem of increasing the performance properties of aluminum alloy D16 for possible more efficient use in the fields of transport engineering. A property modification tool is a high current relativistic electron beam. The irradiation occurs in a vacuum. The peculiarities of the layer distribution of characteristic zones resulting from irradiation are investigated. Metallographic and fractographic analysis is carried out, and microhardness values are measured.

Titanium VT22 alloy was irradiated in the TEMP-A accelerator with the high current electron beam with the energy of 350 keV, beam current of 2 kA, pulse length around 5 μs, and beam diameter of 45 mm. The irradiation was performed for three samples with 1 to 3 pulses separately. Numeric simulations of the temperature distributions in the targets were conducted using the thermoelastic ablation model. The microstructural and mechanical properties of the irradiated alloy were studied using microhardness testing, metallography and fractography analysis.

Natural diamond remains the source of many interesting effects and finds that are difficult to reproduce or detect in synthetic crystals. Herein, we investigate the photoluminescence (PL) of more than 2000 natural diamonds in the range 800–1050 nm. PL spectra were registered with excitation at 405, 450, 488 (Ar+), and 787 nm. The investigation revealed several systems that were not previously described. Some new dislocation-related systems were discovered in the spectra of crystals with signs of plastic deformation. They are four sets of doublets 890/900.3 nm, 918/930 nm, 946.5/961.5 nm, and 981/994 nm; four lines at 946, 961.5, 986, and 1020 nm. In low-nitrogen diamonds, they are accompanied by a line at 921 nm. Unreported vibronic systems with zero-phonon lines at 799.5, 819.6, 869.5, and 930 nm were revealed. In most cases, the systems were accompanied with doublet 883/885 of the simplest Ni-related center. We assigned these systems to Ni-related centers of different complexity. The results expand opportunities to restore growth conditions and thermal history of diamond crystals. The detection of new shallow centers expands the prospects of diamond as an optic and semiconductor material for applications in the NIR range.

The purpose of the study was to estimate the doses to the Voronezh region population from natural sources of ionizing radiation and the technologically altered background in the territory of Voronezh Region. The data of forms of state statistical observation No. 4-DOZ “Information on the doses of population exposure due to natural and technologically altered background” for 20102017 and the radiation and hygienic passport of the territory of the Voronezh Region were used. The average annual per caput effective dose due to all types of ionizing radiation remains stable with a slight upward trend and lies in the range from 2.925 (2010) to 3.656 mSv (2017). Natural sources are the main dose-forming factors for the population. Their annual contribution to the annual effective dose ranges from 74.96 to 83.65%. The leading contribution to the total dose from natural sources is the exposure due to the inhalation of radon isotopes: it ranges from 37.6 to 51.1%. In second place,there is the share of external exposure from sources of terrigenous origin, which ranges from 21.2 to 28.9% of the total dose. The average annual effective dose of natural exposure to humans varies from 2,355 to 2,980 mSv / year, the exposure from radon – from 0,83 to 1,65 mSv / year. The dose from technogenic-altered radiation background, including global radioactive fallout due to atmospheric nuclear tests and due to past radiation accidents are insignificant (0,062 mSv / year). Its annual contribution to the total dose is less than 2%. Based on the results of the assessment of the indicators characterizing the level of exposure of sources of ionizing radiation to natural and technogenic-altered radiation background, no excess of radiation safety standards has been recorded. The situation associated with exposure to ionizing radiation sources in the Voronezh region has been described as safe for the last 8 years.

The collection of the Ural, Anabar and Brazilian diamonds is studied by infrared spectrometry method. For the reconstruction of the thermal formation conditions of diamond crystals, V. Taylor’s diagrams are made with the calculated isotherms. Graphs of the ratio of B1 and B2 defects are drawn. Conclusions about the thermal conditions of the Ural diamonds formation and their possible affinity to the specific and type of indigenous sources are made.

The purpose of the study was to assess the doses of personnel and the population at the expense of all the main activities and sources of radiation in the territory of the Voronezh region. The data of the forms of state statistical supervision No. 1-DOZ “Information on the doses of personnel from persons under normal use of technogenic sources of ionizing radiation”, No. 3-DOZ “Information on radiation doses of patients during X-ray radiology studies”), No. 4-DOZ “Information on radiation doses of the population due to natural and technogenically altered background” for 2010-2016 and the radiation and hygienic passport of the territory of the Voronezh Region. Based on the results of monitoring the radiation situation, the situation associated with the impact of ionizing radiation sources in the Voronezh Region has been characterized as safe for the past 7 years. The average annual effective dose per 1 inhabitant due to all ionizing radiation remains stable with a slight upward trend and lies in the range from 2.925 (2010) to 3.399 mSv (2016). In the structure of the collective dose of the population of the Voronezh region, the dose from natural sources is 83.65%, from medical sources – 16.06%, from technogenically changed background radiation, including global fallout and accident at the Chernobyl nuclear power plant – 0.18%, from the activities of enterprises using Sources of ionizing radiation – 0.11%. The average annual effective dose of natural exposure to humans varies from 0.660 to 0.704 mSv / year, natural radiation from radon from 0.832 to 1.465 mSv / year. The average effective dose from medical research for the procedure for the study period was 0.27-0.40 mSv and tends to decrease due to the introduction of modern low-dose medical diagnostic equipment. On the territory of the Voronezh region, there were no population groups with an effective radiation dose exceeding 5 mSv / year. Gamma-background in the region in 2010-2016. Did not exceed the natural level and amounted to 0.08 – 0.16 μSv / h. The excess of hygienic standards for the effects of ionizing radiation sources on humans has not been recorded.

An asymmetric model of virial expansion of the Gibbs free energy of solution, VD-AS, was suggested. Partial and molar thermodynamic functions of UO2(ClO4)2–H2O, UO2Cl2–H2O, and UO2(NO3)2–H2O binary solutions at 25°C were calculated using this model. The calculations show that the solutions are characterized by different, sometimes extremely large, deviations from ideality. The suggested model is considerably more accurate and stable than the most widely used Pitzer’s model of electrolyte solutions.

Pulsed high-current quasi-relativistic electron beam irradiation was used to study the formation mechanism of aluminum-copper composite. The composite was obtained through intense electron ablation and rapid solidification. The irradiation of the complex aluminum-copper target was performed using the TEMP facility with accelerating voltage of 350 kV, pulse duration of 5 μs, and beam current of 2 kA.

The paper presents some data on physico-chemical study of the C70-carboxyfullerene water solutions. The data on temperature dependence of solubility in water, concentration dependence of density, specific conductivity, molar conductivity, dissociation constant, and dynamic light scattering are presented and characterized; composition of equilibrium solid phase in binary C70-carboxyfullerene + water system is determined.

Based on the Voronezh hydrometeorological service official statistics analysis, the pollutants (formaldehyde and carbon black) dynamics regularities depending on the various meteorological parameters combination - air temperature, wind speed, relative humidity. A positive relationship was established between atmospheric pollution growth with formaldehyde and air temperature. As the wind speed and the air relative humidity increase, the formaldehyde and soot concentration in the urban atmosphere, as a rule, decreases. The carcinogenic risk maximum permissible level to public health, causing concern, has been established. The obtained patterns can be used to predict the city’s atmosphere technogenic pollution level depending on meteorological conditions. Based on the official statistic analysis from the Voronezh Hydrometeorological Service, the pollutants (formaldehyde and carbon black) dynamics patterns are investigated depending on various meteorological parameters’ combination - air temperature, wind speed, relative air humidity. A positive relationship has been established between the increase in atmospheric pollution with formaldehyde and air temperature. With increasing wind speed and relative humidity, the formaldehyde and soot concentration in the city atmosphere, as a rule, decrease. The maximum permissible carcinogenic risk level to public health has been established, causing concern. The obtained patterns can be used to predict the city’s atmosphere technogenic pollution level, depending on meteorological conditions.

The reaction of ammonium and phosphonium iodides R3R′EI (E = N, P; R = H, Me, Bu, Ph; R′= H, Me, Bu, Am) with mercury iodide (I) (red polymorph) in acetone in 1: 1 and 1: 2 ratios (mol/mol) gave mercury complexes [H4N]n+[HgI3]n− (II), [Me3NH]n+[HgI3]n− (III), [Me3NH]2n+[Hg4I10]n2− (IV), [Me4N]n+[HgI3]n− (V), [Me3NBu]2+[Hg2I6]2− (VI), [Bu4N]2+[Hg2I6]2− (VII), [Ph3PAm]2+[Hg2I6]2− (VIII), [Me4N]2n+[Hg4I10]n2− (IX), [Me3NBu]2n+[Hg4I10]n2− (X), [Bu4N]2n+[Hg4I10]n2− (XI), and [Ph3PAm]2n+[Hg4I10]n2− (XII). According to X-ray diffraction data, crystals of I are composed of (HgI2)n polymeric layers in which each mercury atom having a tetrahedral environment (two IHgI angles equal to 103.16° and four angles of 112.72°) is bonded to four neighboring mercury atoms through iodine atoms (I-Hg, 2.818 A). In the tetrahedral cations of the complexes, the nitrogen and phosphorus atoms each have a distorted tetrahedral coordination. In the centrosymmetric binuclear [Hg2I6]2− anions, the mercury atoms having tetrahedral coordination lie in two almost perpendicular planes Hg2I6. In the polymeric anions of II and III, the HgI2 groups are linked to each other through bridging iodine atoms. The crystals of IV consist of tetrahedral trimethylammonium cations disordered over two positions and polymeric [Hg4I10]n−, anions in which the eight-membered Hg4I10 rings are connected to one another through bridging iodine atoms to form a polymeric ribbon.

Analysis of internal structure in large IIb-type high pressure-high temperature (HPHT) synthetic single-crystal diamond are presented. The concentration of boron impurity in different growth sectors varies from 0.02 to 10.3 ppm. It is shown that in the manufacturing of synthetic diamond plates, internal inhomogeneities of the diamond should be taken into account; plates with different characteristics can be cut from one diamond, each of which can be used for its own purpose.

Complexes [Ph3MeP]2+[BiI3.5Br1.5(C5H5N)]2− · C5H5N(I), [Ph4Bi]4+[Bi4I16]4− · 2Me2C=O (II), and [Ph3(iso-Am)P]4+[Bi8I28]4− · 2Me2C=O (III) were synthesized by reactions of bismuth iodide with triphenylmethylphosphonium bromide, triphenylbismuthonium sulfosalicylate, and triphenylisoamylphosphonium iodide, respectively. The crystal structures of complexes I–III were determined by X-ray crystallography. The complexes contain, in addition to cations and solvent molecules, mono-, tetra-, and octanuclear anions, in which bismuth atoms are in octahedral coordination.

Complexes with cadmium-containing anions [Ph3EtP]2+[Cd2I6]2− (I), [Ph3(iso-Pr)P]2+[CdI4]2− (II), [Ph3(iso-Bu)P]2n+[Cd2I6]n2− (III), and [Ph4P]2+[Cd2I6]2− (IV) were synthesized by the reaction of triphenylalkylphosphonium halides with cadmium iodide. The phosphorus atoms in the cations have a distorted tetrahedral coordination, as well as the cadmium atom in the mononuclear [CdI4]2− anion of complex II. The binuclear [Cd2I6]2− anions contain two terminal (t) CdI2 fragments linked to each other through two bridging (b) iodine atoms (Cd-Ib, 2.8626 and 2.8934 A in I, and 2.8652 and 2.8780 A in IV). The bond lengths Cd-It in I and IV are comparable (2.7245 and 2.7214 A in I and 2.7130 and 2.7252 A in IV). The anions of compound III are polymeric; the structural fragments [Cd2I6]2 (Cd-Ib, 2.8384 A; Cd-It, 2.6739 A) are associated by means of iodine atoms (I(1)…Cd(2A) 2.7973 A).

The complexes [Ph3BuP] 2 + [Bi2I8 · 2Me2C=O]2− (II) and [Ph3BuP] 2 + [Bi2I8 · 2Me2S=O]2− (III) are synthesized by the reactions of triphenyl(n-butyl)phosphonium iodide (I) with bismuth iodide in acetone and dimethyl sulfoxide. In the cations of complexes I–III, the P atoms have a distorted tetrahedral coordination (CPC angles 106.3(2)°–112.0(3)°). The butyl group in cation I is disordered over two positions. In the binuclear centrosymmetric anions of structures II and III, the octahedrally coordinated bismuth atoms are linked in pairs by two bridging (br) iodine atoms (Bi-Ibr 3.1508(7) and 3.2824(8) A in compound II, 3.1961(3) and 3.3108(3) A in complex III), which are coplanar to four terminal (t) iodine atoms (Bi-It 2.9260(7) and 2.9953(6) A in complex II, 2.9206(3) and 2.9786(3) A in complex III). The two remaining positions at the bismuth atom are occupied by the iodine atom (Bi-It 2.8531(7) A in complex II, 2.8984(3) A in complex III) and O atom of the organic molecule (Bi-O 2.747(6) A in complex II, 2.507(3) A in complex III).

The complexes [Ph3(n-Pr)P]2+[Bi2I8 · 2Me2S=O]2− (I), [Ph3(iso-Bu)P]2+[Bi2I8 · 2Me2S=O]2− (II), [Ph3(n-Bu)P]2+[Bi2I8 · 2Me2S=O]2− (III), and [Ph3(n-Am)P]2+[Bi2I8 · 2Me2S=O] 2− (IV) are synthesized by reactions of triphenylalkylphosphonium iodide with bismuth iodide in dimethyl sulfoxide. In all complexes, the P atoms in cations have a distorted tetrahedral coordination (the CPC angles vary from 106.4(8)° to 114.8(2)°). In the dihedral centrosymmetric anions, the octahedral bismuth atoms are bound to each other by two bridging (br) iodine atoms (Bi-Ibr 3.167(1), 3.273(1) A (I); 3.1557(2), 3.2589(2) A (II); 3.1961(3), 3.3108(3) A (III); 3.1913(4), 3.3161(4) A (IV)), which are coplanar to four terminal (t) iodine atoms (Bi-It 2.956(1), 2.989(1) A (I); 2.9557(2), 2.9872(2) A (II); 2.9206(3), 2.9706(3) A ( III ); 2.9328(4), 2.9890(4) A (IV)). Two remaining positions at the bismuth atoms are occupied by the iodine atom (Bi-I 2.987(1) A (I); 3.0051(2) A (II); 2.8984(3) A (III); 2.9046(4) A (IV)) and the dimethyl sulfoxide molecule (Bi-O 2.458(12) A (I); 2.430(2) A (II); 2.507(3) A (III); 2.544(4) A (IV)).

A number of complexes with bismuth-containing anions, [Ph3MeP]6+[BiI3Br3]3− [Bi2I6Br3]3− · H2O2 (I), [Ph3EtP]3+[Bi2I9]3− (II), [Ph3MeP]3+[Bi3I12]3− (III), [Ph3(iso-Pr)P]3+[Bi3I12]3− · 2Me2C=O (IV), and [Ph4Bi]3+[Bi5I18]3− (V), were obtained by reactions of triphenylphosphonium halides and tetraphenylbismuth 3-carboxy-4-hydroxybenzenesulfonate with bismuth iodide. The central atom in the complex cations has a distorted tetrahedral coordination. In the mononuclear octahedral anion [BiI3Br3]3−, the bromine and iodine atoms are located on the opposite octahedron faces. The binuclear [Bi2I6Br3]3− anion contains three bridging iodine atoms and terminal BiI3 and BiBr3 fragments; in the centrosymmetrical [Bi2I9]3− anion, the Bi-I bond lengths (2.933–3.360 A) are comparable with similar bonds in I (2.935–3.257 A). In the anion of complex III, each of terminal BiI3 groups is linked to the central Bi atom by two μ2- and one μ3-iodine bridges (the BiBiBi angle is 101.54°). In the anions of complexes IV and V, the bismuth atoms of Bi3 and Bi5 groups occur on a straight line.

We consider results obtained from experimental and calculated evaluation of the efficiency with which nitrogen oxide emission is suppressed in the furnaces of TPE-214 and BKZ-160-100 boilers during combustion of high-reaction coals in them with the use of staged technologies, and the possibilities of reducing the level of harmful emissions can be seen from these results.

The complexes [Et2NH2]3+[BiCl6]3− (I), [NH4]+[BiI4(C5H5N)2]−·2C5H5N (II), [Ph3MeP]2+[BiI5]2− (III), [Ph3MeP]2+[BiI5(C5H5N)]2−·C5H5N (IV), [Ph3MeP]3+[Bi3I12]3− (V), [Ph3(i-Pr)P]3+[Bi3I12]3−·2Me2C=O (VI), [Ph3BuP]2+[Bi2I8·2Me2C=O]2− (VII), and [Ph3BuP]2+[Bi2I8·2Me2S=O]2− (VIII) were obtained by reactions of bismuth iodide with ammonium and phosphonium iodides in acetone, pyridine, or dimethyl sulfoxide.

The morphology of fiber structures has been studied and the kinetics of their formation and growth at high homological temperatures upon superplastic deformation of the AMg6 and 1420 aluminum-based alloys containing viscous liquid-phase inclusions at the intercrystalline boundaries has been proposed. It has been found that, according to their morphology, the fiber formations can be divided into two types, namely, thin smooth cylindrical fibers and fibers whose specific feature is the presence of one or several droplike formations on their surface. The surface of fibers and grain edges to which the fibers are connected is strongly oxidized; the atomic concentration of magnesium in various regions of fibers and grains is different and is higher than that in the specimen as a whole. It was shown that the fibers were formed upon pore and crack opening as a result of viscous flow of solid-liquid material which is present at the intercrystalline boundaries.

The electrophysical characteristics of composite media consisting of finely dispersed T-10 000 ferroelectric ceramics and dielectric fluids are experimentally investigated. Transformer oil, dibutyl phthalate, cyclohexanol, and sulfolane are used as dielectric fluids. The permittivity of compositions e is directly proportional to that of the fluids. Its dependence on the concentration of the ferroelectric ceramics is nonlinear and is well consistent with the known Nielsen formula up to the concentration of 55 vol %. The permittivity of a 50% composition exceeds by a factor of five that of the fluid. The maximal coefficient of e increasing approximately equals 20 upon adding two ceramics fractions of different particle sizes to the composition. The specific resistance of compositions decreases as the permittivity of the fluid increases. The concentration dependence of the specific resistance of the T-10 000 ferroelectric ceramics–dibutyl phthalate mixture has a minimum at a concentration of 30–40 vol %. A new mechanism of the surface electric conductance is suggested, which is associated with a decrease in the dissociation energy in the surface layer under the effect of image force. The electric strength of compositions decreases as the permittivity of the fluid increases. The obtained experimental data agree with the bubble model of breakdown ignition.

Effects of molybdenum replacement by tungsten in steels of the bainitic, martensitic, and martensitic–ferritic classes containing 2.5%, 8% and 11% Cr, respectively, were investigated. The phase composition and structure of the bainitic steels were varied by changing the cooling rates from the austenitization temperature (from values typical for normalization up to V=3.3 × 10−2°C/s) and then tempering. The steels were irradiated to a fluence of 4×10 23 n / m 2 (⩾0.5 MeV) at 270°C and to fluences of 1.3×1023 and 1.2×10 24 n / m 2 (⩾0.5 MeV) at 70°C. The 2.5Cr–1.4WV and 8Cr–1.5WV steels have shown lower values of the shifts in ductile–brittle transition temperature (DBTT) under irradiation in comparison with corresponding Cr–Mo steels. Radiation embrittlement at elevated irradiation temperature was lowest in bainitic 2.5Cr–1.4WV steel and martensitic–ferritic 11Cr–1.5WV steel. The positive effect of molybdenum replacement by tungsten at irradiation temperature ∼300°C is reversed at Tirr=70∘C.

The present work is an attempt to obtain data concerning the influence of neutron and ? irradiation upon hydrogen retention in V-4Cr-4Ti vanadium alloy. The experiments on in-pile loading of vanadium alloy specimens at the neutron flux density 1014 n/cm2s, hydrogen pressure of 80 Pa, and temperatures of 563, 613, and 773 K were carried out using the IVG.1M reactor of the Kazakhstan National Nuclear Center. A preliminary set of loading/degassing experiments with non-irradiated material has been carried out to obtain data on hydrogen interaction with vanadium alloy. The, data presented in this work are related both to non-irradiated and irradiated samples.

Hydrogen permeation through EP-750 and EI-914 stainless steels and EK-63 nickel alloy with a diffusion-type Al+Cr+Si coating and a TiN ion-plasma deposited coating was measured. It is shown that the Al+Cr+Si coating reduces by several times hydrogen permeation into the steels and builds a very effective hydrogen protective barrier for the nickel alloy. Deposition of the TiN coating results in a reduction of permeability by 2–4 times depending on the material. The annealing of coated samples in a hydrogen atmosphere at elevated temperatures results in the degradation of the protective coating.

The isothermal (20°C) solubility of fullerene C70 in solvents of the homologous series of monocarboxylic acids C n − 1H2n − 1COOH (n = 1–9) and polythermal solubility over the temperature range 20–80°C of fullerene C70 in solvents of the homologous series of monocarboxylic acids C n − 1H2n − 1COOH (n = 4–9) were studied. The corresponding solubility diagrams were obtained and characterized.

The polythermal solubility of fullerene C60 and a fullerene mixture (60 wt % C60 + 39 wt % C70 + 1 wt % higher fullerenes Cn, n = 76, 78, 84, 90...) in valeric and caproic acids was studied in the temperature range 20–80°C. The solubility diagrams are presented and characterized.

The paper relates to the determination of the amount of nuclear material contained in a closed, concrete lined vault at the Aktau fast breeder reactor in Kazakhstan. This material had been disposed into the vault after examination in an experimental hot cell directly above the vault. In order to comply with IAEA Safeguards requirements it was necessary to determine the total quantities of nuclear materials — enriched uranium and plutonium — that were held with Kazakhstan. Although it was possible to determine the inventory of all of the accessible nuclear material — the quantity remaining in the vault was unknown. As part of the Global Threat Reduction Programme the UK Government funded a project to determine the inventory of these nuclear materials in this vault. This involved drilling three penetrations through the concrete lined roof of the vault; this enabled the placement of lights and a camera into the vault through two penetrations; while the third penetration enabled a lightweight manipulator arm to be introduced into the vault. This was used to provide a detailed 3D mapping of the dose rate within the vault and it also enabled the collection of samples for radionuclide analysis. The deconvolution of the 3D dose rate profile within the vault enabled the determination of the gamma emitting source distribution on the floor and walls of the vault. The samples were analysed to determine the fingerprint of those radionuclides producing the gamma dose — namely 137Cs and 60Co — to the nuclear materials. The combination of the dose rate source terms on the surfaces of the vault and the fingerprint then enabled the quantities of nuclear materials to be determined. The project was a major success and enabled the Kazakhstan Government to comply with IAEA Safeguards requirements. It also enabled the UK DECC Ministry to develop a technology of national (and international) use. Finally the technology was well received by IAEA Safeguards as an acceptable methodology for future studies.

Hydrogen gas driven permeation experiments were conducted with the vanadium alloy VCr6Ti5 in the temperature range 423–1073 K and input pressures 102–103 Pa. Hydrogen permeation through this material was shown to be limited by surface processes and permeated fluxes to be proportional to input pressures P more than P12, in indicated ranges of temperatures and pressures. Sticking, (S), recombination coefficients, (b), and solubility constants, (CS), in VCr6Ti5 have been extracted from the permeation experiments in the frame of a hydrogen permeation model, being limited by adsorption and desorption processes: ; . These values do not agree very well with the literature data obtained for other vanadium alloys. Thus, for more correct determination of these values, the experimental results must be probably processed taking into consideration the rate constants of transfers from surface into the bulk and emergence from the bulk onto the surface.

Experiments on thermal stimulated hydrogen release of irradiated and control samples of RGT-graphite were carried out. Processing of two TDS peaks at temperatures near 770 K and 1100 K in a frame of second order desorption model gives the values of activation energies 2.8 eV/H2 and 4.0 eV/H2. Processing of a third peak at a temperature near 1300 K, which appeared only for graphite samples irradiated in hydrogen, allows to obtain hydrogen diffusivity in graphite grains D = 1, 8 m2/s 10−4exp(−2.5 eV/kT). It was also shown that simultaneous influence of reactor irradiation and exposition to hydrogen could increase hydrogen retention in graphite.

Experiments on gas release of reactor-irradiated beryllium samples were carried out and compared to control samples. The simultaneous influence of reactor irradiation and exposure to hydrogen results in more hydrogen retention in beryllium, than if beryllium is initially irradiated and then exposed to hydrogen. Appearance of low temperature peaks at 460 K and 540 K with 0.71 eV/atom and 0.84 eV/atom desorption activation energies, respectively, assessed in a frame of a second order desorption model, is mainly responsible for the increase in hydrogen content. These peaks can be attributed to chemical hydrogen bonds with surface oxide. The simultaneous influence of hydrogen and nuclear reactor irradiation at a temperature of 1150 K was assumed to increase significantly microcrack formation near the surface of beryllium samples, resulting in an increase in low temperature peak intensities.

This work develops the technique of hydrogen diffusion parameters measurements in metal materials during the process of reactor irradiation. The possibility of irradiation stimulated hydrogen diffusion for 08Cr18Ni10Ti was obtained. Constants of diffusion, permeation and solution while the process of irradiation were measured as a result of the work. Formally calculated activation energies of diffusion and permeation were obtained to decrease while the solution heat was increasing. 5 refs., 4 figs., 1 tab.

This work deals with the results of studies of the processing and properties of α-C:H films obtained in a Hall accelerator plasma using hydrocarbons with various types of carbon atom bonds. According to the analysis of IR, UV and Raman spectra, it is suggested that in α-C:H films obtained from C2H2 sp2 bonds are predominant, in those obtained from CH4 both sp2 and sp3 bonds are predominant, while in the films obtained from C2H4 there are mostly sp3 bonds.

Extraction equilibria of the liquid(I)-liquid(II) type have been studied for the first time in a system containing light fullerenes C60 and C70. The experiments were performed with a five-component mixture of fullerene C60, fullerene C70, o-xylene, ibutylamine, and water at 25°C. Isothermal diagrams describing the distribution of fullerene components between separating liquid phases have been obtained. The distribution coefficients of fullerenes (C60 and C70 concentrations in the xylene phase relative to those in the amine phase) are found to be almost constant and approximately equal to ∼16.1 for both C60 and C70.

A new nitrogen-containing fertilizer was obtained by oxidative ammonolyis from wood waste. The chemical composition of the fertilizer was studied by functional chemical analysis. The fertilizer was tested in field conditions.

Oxidative ammonolysis of mechanicochemically activated lignocarbohydrates produces N-containing derivatives (5.98-7.45% N) with 15-35% readily cleaved N and 5.43-6.99% COOH

One of the main concerns of fission and fusion reactors development is the ecological aspect of their operation. If we consider fusion reactor operation with high energy and density neutron fluxes, the problem of activated materials management will be very important. To reduce the level of induced radioactivity it is supposed to use reduced-activation steels, for example F82H steel. Nevertheless the main reason of these steels application is their good stability against swelling and embrittlement. Because of possible application of this steel in the design of DEMO liquid metal blanket it is very important to know the parameters of its interaction with hydrogen isotopes for evaluation of tritium uptake and permeation flux in structural elements made of this material.

The deuterium penetration rates through beryllium membrane (98%) were measured in the temperature range 673…873K with the surface element composition control. Having processed the experimental results, the effective diffusivities and permeability constants in the beryllium sample were determined. Using multilayer penetration theory, the deuterium diffusion coefficients in FP-56 sort beryllium were calculated: D 0 = 9.0·10 -12 m 2 /s; E = 14.9 kJ/mol. Surface sample study in a wide temperature range, with AES technique, showed only beryllium oxide presence on the surface. Any changes of the surface element composition were not observed up to temperature 1273K.