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Materials based on molybdenum-aluminium-carbon compounds have a considerable potential for use under intense wear conditions at elevated temperatures. This paper presents the experimental results of self-propagating high-temperature synthesis of compounds within the Mo-Al-C system. By combining two processes: SHS of the elements and SHS-metallurgy, cast materials containing the Mo3Al2C, Mo2C, Mo3Al, and Mo3Al8 phases were obtained. The experiments used mixtures with compositions calculated according to the ratio (1 - α)(3MoO3-8Al-C)/α(3Mo-2Al-C), where a varied in the range from 0 to 1. The synthesis was carried out in a laboratory reactor of 3 L volume at an initial argon pressure of 5 MPa. The mass of the initial mixtures in all experiments was 20 g. The process of combustion was initiated by a 0.5 mm diameter molybdenum wire spiral by applying 28 V voltage to it. The resulting end products were studied by X-ray diffraction and local microstructural analysis. A significant influence of the ratio of the initial reagents on the synthesis parameters, phase composition, and microstructure of the target products was established. Introduction into the high-exothermic mixture 3MoO3-8Al-C inert “cold” mixture 3Mo-2Al-C leads to an increase in the content of carbide phases in the ingots. The possibility of obtaining cast materials based on the triple phase Mo3Al2C, the maximum content of which is 87 wt. % at the content of the “cold” mixture in the charge α = 0.4 is shown. The presence of secondary phases of molybdenum carbide (Mo2C) and molybdenum aluminides (Mo3Al8 , Mo3Al) in the final products is due to a change in the composition of the initial mixture caused by the ejection of components during combustion and insufficient existence time of the melt formed in the combustion wave.

The aim of the study was to analyze the resistance of 21 Microdochium nivale strains (fungi that cause pink snow mold in winter crops), living within a single area and a single crop (winter rye), to fungicides that differ in chemical nature and mechanisms of action as well as to test the interconnection between levels of virulence and fungicide resistance of strains. The virulence of M. nivale strains was determined on detached leaves of rye (Ogonek variety) plants as well as on whole plants grown under sterile conditions in vitro. The resistance of strains to fungicides (Provisor (a.s. azoxystrobin) and Ferazim (a.s. carbendazim)) was determined by inhibition of mycelium growth. As a result of the experiments, more strains (13) capable of growing in the presence of Provisor were revealed than Ferazim-resistant strains (2); however, Ferazim-resistant strains had a greater level of resistance (5-16% of growth inhibition) than Provisor-resistant strains (63-94 % of growth inhibition). A negative correlation (Spearman's correlation coefficient -0.604 and -0.532) between the level of virulence of M. nivale strains and the level of their susceptibility to Provisor was found. This evidently means that the acquisition of resistance to Provisor by M. nivale strains is accompanied by an increase in their virulence. No correlations were found between the fungicide resistance of M. nivale strains and their attribution to one or another phylogenetic group, to which the strains were assigned based on the nucleotide sequence of the ITS2 (internal transcribed spacer 2) region. The study shows that for choosing the fungicide application strategy, it is necessary to analyze phytopathogen populations for the presence of strains that are simultaneously characterized by high virulence and resistance to various fungicides and also take into account that the adaptation of fungi to certain fungicides can be accompanied by an increase in their virulence, which will negatively affect the phytopathological state of agrocenosis.

In recent years, myelosai (milleran) has become widely used to treat patients with chronic myelosis.

The article indicates pomological signs of tangerine: peel and pulp color, number of slices, fruit size, shape, taste, aroma and juiciness of a fruit. Physicochemical characteristics of tangerine fruits are shown: sugar, acidity, dry matter, vitamin C. A comparative biochemical assessment of tangerine fruits growing in the subtropical zone of the Krasnodar Territory and imported ones is carried out. The studies have been carried out in VNIIITsiSK in Sochi.6 tested varieties of imported tangerine fruits were infected with penicillosis (Penicillium expancym Link) and anthracnosis (the pathogenic agent is Colletotrichum gloeosporioides Penz. Fungus). A physiological peta disease (deep pit) was found, which affected fruits on trees and appeared during storage with temperature regime violation [13]. Biochemical analysis revealed a low concentration of ascorbic acid, acidity and an increased content of dry soluble substances in the imported fruits in comparison with fruits grown in the humid subtropics of Russia.

Cast composite material based on Cr2AlC MAX phase has been prepared by metallothermic self-propagating high-temperature synthesis (SHS) from a mixture of powders of chromium oxide, aluminum, and carbon. The experiments have been performed using an SHS reactor with a volume V of 3 L under an excess inert gas (Ar) pressure (P = 5 MPa). The prepared material has been studied by X-ray diffraction analysis, scanning electron microscopy, and local microstructural analysis. The quantitative analysis has been performed by the Rietveld method. The electrical resistivity was measured in the 100–1300 K temperature range. The resulting material is an electrical conductor with metallic conductivity in the 100–1300 K temperature range, and has the electrical resistivity of the same order as the samples containing 100% Cr2AlC.

Changes in characteristics of the upper soil horizons in dark coniferous forests in the course of their postfire restoration were assessed. The studies were carried out in the northern taiga forests exposed to fire 8 to 400 years ago in the Kola Peninsula and in the middle taiga forests burned 70 and more than 500 years ago in the northern Cis-Ural region (Pechoro-Ilychskii State Biospheric Reserve). Samples from 23 soil pits on 20 test plots were analyzed. The actual acidity, loss on ignition, contents of exchangeable K, Ca, and Mg and mobile Mn, Fe, and Zn were determined. Two boundaries (~80 and 160–200 years after fire) and three main periods in the postfire dynamics of the upper soil horizons properties were established. The ash and Fe content in the litter was found to decreases about 80 years after the fire. In 160–200 years after fire, the thickness of the forest litter is restored and stabilized at the level of about 9.7 (8.3–10.4) cm; the pH value and the Ca, K, and Mn concentrations in the litter become lower. Thus, it can be concluded that the properties of soils under dark coniferous forests of the European North considerably change in the course of postfire successions.

The main problems of establishment a slow growth in vitro collection of citrus and other tree crops cultivars are high degree of fungal contamination of bud explants and low growth potential of shoots. In this regard, the aim of current research is to assess the efficiency of decontamination procedure and the possibility of tissue culture initiation and slow growth conservation of valuable lemon cultivars. The best results of surface sterilization were obtained using immersion solutions of 0.3 % Veltolen – 25 minutes or 10 % Domestos – 25–30 minutes. In these treatments, 27.7–33.0 % of aseptic explants were obtained, respectively. However, after the third subculture, the yield of aseptic viable explants decreased till 10 % as a result of secondary contamination by endophytic fungi. The addition of biocide (“Gavrish”) in a nutrient medium at a concentration of 1 ml/l helped to increase the yield of aseptic viable explants till 50 %. However, after the third subculture the photosynthetic activity and the pigments content as well as growth rate decreased. Plants dropped yellowish leaves and eventually died. Thus, 37.35 % of plantlets survived after 8 months of conservation, and only 14.6 % survived after 10 months. Even after the third month of conservation significant decrease in the viability index and the coefficient of photosynthetic activity occurred in plants. Chlorophyll a in leaves decreased from 1.59 to 1.14 mg/g during 12 months in vitro conservation. The similar tendency observed on clorophyll b and carotenoids content. The experiments were carried out for 5 years using different lemon cultivars and other citrus varieties and cultivars. Thus, micropropagation and slow growth in vitro conservation of valuable lemon cultivars are still problematic and requires new technical solutions due to the low growth potential of plantlets raised from the mature buds that is consistent with the data of other researchers.

Bacterial SpoT-dependent SR was activated in Pectobacterium atrosepticum when pathogen infected potato as well as tobacco plants. Pba induced plastid stringent response in tobacco plants, but not in potato plants. Jasmonic acid defense pathway was activated in tobacco plants, provoking rapid maceration of plant tissues. Salicylic acid defense pathway was induced in potato plants, probably ensuring a more prolonged coexistence of the phytopathogen with its host.

The goal of this work was to improve the efficiency of early detection of microcalcifications, the earliest indicators of breast cancer. Studies have shown that the presence of isolated clustered microcalcifications in the mammary gland significantly increases the range of variation of effective atomic number and considerably changes its distribution. Conventional, subtraction, or dividing mammography or their linear convex combination may fail to visualize isolated clustered microcalcifications. However, the presence of microcalcifications in the mammary gland can be determined analytically from the distribution of the extreme terms of an ordered series of effective atomic numbers in the mammary gland. Then, the coordinates of the isolated clustered microcalcifications can be calculated. The distribution of the effective atomic numbers in healthy tissue without microcalcifications is symmetric and close to normal, while breast tissue with even a single isolated cluster of microcalcifications is characterized by an asymmetric distribution and high values of the maximum effective atomic numbers. An algorithm for calculating the coordinates of isolated microcalcifications is suggested.

When fire extinguishing foam is applied for fire suppression of flammable liquid in the tank, after the most part of the liquid mirror is already covered by a fire extinguishing foam layer, the fuel continues to burn at the side of the tank. This rather complex case is often implemented in practice, but it wasn’t fully described in the existing theoretical literature. Extinguishing of these last fire sources occur in the following two cases: § cooling of a free side of the tank to a temperature at which the side heated by flame ceases to serve as a source of ignition of fuel vapors; § lowering of the temperature of the combustible fluid located at the side surface of the reservoir to a temperature at which the ignition of the combustible mixture formed by mixing of the fuel vapor with air can not occur. The article presents the analysis of the two cases needed to extinguish remaining pockets of burning at the side of the tank. For the first case (cooling of a free side of the tank to a temperature at which the side heated by flame ceases to serve as a source of ignition of fuel vapors), the mathematical model describing the temperature change during the cooling of the sides of the reservoir was developed. Analytical solutions with certain assumptions were obtained. The expression that defines the time of extinguishing of flammable liquid was also obtained. The values of heat transfer coefficient calculated with the usage of the resulting equation together with the available experimental data obtained in the burning tank, are presented in the paper. The values of the heat transfer coefficient are 0.34¸0.51 W·m -2 ·K -1 . For the second case (lowering of the temperature of the combustible fluid to a temperature at which the ignition of the combustible mixture can not occur), the resulting expression describes changes in temperature of the side of the tank during cooling by fire extinguishing foam. The expression was derived from the heat equation with a number of assumptions and the usage of integrating methods of research of physical processes involving integral relations derived from the analysis of differential equations. The obtained equation of temperature change of the side of the tank while cooling by fire suppression foam during extinguishing of flammable liquid, can be later used in the modeling of processes of extinguishing of tanks and in calculating of the flow rate of the foam.

The modern history of organic farming in Russia began in 1989 with the implementation of the state program “Alternative Agriculture”. Organic agriculture in Russia was initially considered as a condition and mechanism for the development of small and medium agricultural forms of production. The increase in the production of agricultural products and food in excess of the normative requirements, ensuring the country’s food security led to the expansion of exports. Russia’s aptitude to uphold fulfillment with global standards and be competitive in world markets where ecologically clean agricultural products are in demand is quite high: huge reserves of land in Russia, the introduction of ecological farming systems must be carried out on huge areas, coordinated with a large number of small owners. Information support for farmers about new, more efficient technical means, biotechnologies in organic agriculture and certification of organic products for environmental friend-liness, safety of manufactured products, the use of intensive biotechnologies, financial support of organic agriculture, processing and sale of organic products remain problematic.

The idea of creating a laser thermonuclear installation was considered back in 1960s by Basov N and Krokhin O. [1]. Facility for conducting research near DT-fuel ignition threshold is being commenced at the moment [2], assembly of the laser installation interaction chamber has already been completed. To focus laser sight on the target, off-axis aspherical lenses are used as part of the final optical module (FOM). These lenses are manufactured using the developed technology of forming off-axis aspherical surfaces of optical parts. Combined use of shaping technology and stand for monitoring angular deviations of the surfaces of FOM lenses, allowed us to achieve high quality off-axis aspheric optical elements both in terms of standard deviation of the surface shape, as well as the value of the scattering circle.

The structure and key elements of the information model of horizontal steel tanks and underground tanks, on which the development of intelligent CAD systems are based, are described. The initial model inputs: functions, operating conditions, and basic dimensions of the constructed objects. The result: apparatus design variants that satisfy the initial data and the restrictions of the normative documents. The key elements of the information model: register of elements, model of structure, model of parameters, model of element positioning in space, and model of technical specifications of the designed equipment. A distinctive feature of the proposed model is use of If…Then… type of production rules. The model is designed for use at the stages of structural and parametric synthesis, construction of a 3D model, and drawing up of technical specifications of the designed objects with minimal involvement of the designer.

The report presents modern manufacturing technology of high-precision optical parts used in optical-electronic systems for various purposes. The report also presents the complex technology of automated shaping (TESAF) of aspherical, including off-axis surfaces of optical elements for optical-electronic systems. In this paper we consider various methods of forming optical parts with virtually any aspherization value and with different values of the off-axis parameter (off-axis aspheric), with the achievement of surface shape accuracy in the limit λ/60 ÷ λ/80 (λ = 0,6328 μm), by the criterion of the standard deviation. Optical systems manufactured by TESAF technology are already being successfully used at present.

The high safety requirements imposed on the products made in the nuclear industry determine the need for developing special approaches to metrological support at the State Corporation Rosatom. The particularities of supporting the traceability of measurements in the use of nuclear power are presented.

Condensation removes water vapor molecules from the gas phase and reduces the weight of the air column. This disturbs hydrostatic equilibrium and makes air circulate under the action of the recently described evaporative force. Meesters, Dolman and Bruijnzeel (2009) criticized the physical bases of the new circulation driver with a major claim that the ascending air motions induced by the evaporative force should rapidly restore the hydrostatic equilibrium and become extinguished. Here we respond that in fact these air motions sustain the disequilibrium of air pressure through the reduction of the weight of the air column via condensation that continuously occurs as the ascending moist air cools. In the traditional meteorological paradigm condensation is primarily considered in terms of the effect it has, via latent heat release, on air density, while its immediate effect on the weight of air column is not accounted for. The critique of Meesters et al. is therefore informative in highlighting the traditional lines of thought that should be re-visited to incorporate the new physical knowledge. Such an effort is arguably worthy of undertaking as the evaporative force concept bears tangible potential for solving some of the key problems that are challenging modern atmospheric science.

The low-lying spectra of 8He and 10He nuclei were studied in the 3H(6He, p)8He and 3H(8He, p)10He transfer reactions. The 0+ ground state (g.s.) of 8He and excited states, 2+ at 3.6–3.9 MeV and (1+) at 5.3–5.5 MeV, were populated with cross sections of 200, 100–250, and 90–125 μb/sr, respectively. Some evidence for a 8He state at about 7.5 MeV was obtained. We discuss a possible nature of the nearthreshold anomaly above 2.14 MeV in 8He and relate it to the population of a 1− continuum (soft dipole excitation) with a peak value at about 3 MeV. The lowest energy group of events in the 10He spectrum was observed at ∼ 3 MeV with a cross section of ∼ 140 μb/sr. We argue that this result is consistent with the previously reported observation of 10He providing the new 10He g.s. position at about 3 MeV

6 pages; International audience; Isomeric states in 253No have been investigated by conversion-electron and gamma-ray spectroscopy with the GABRIELA detection system. The 31 micro second isomer reported more than 30 years ago is found to decay to the ground state of 253No by the emission of a 167 keV M2 transition. The spin and parity of this low-lying isomeric state are established to be 5/2+. The presence of another longer-lived isomeric state is also discussed.

Element 112 was discovered at the Heavy Ion Research Laboratory in Darmstadt, Germany in 1996. A decade on, and some of its chemical properties have now been determined. Irradiation of plutonium-242 with intense calcium-48 beams for three weeks produced two atoms of element 112 (not yet officially named, but commonly called ununbium), and that's enough to do some chemistry on if you are quick. Chemically ununbium behaves as a typical element of the group 12 in the periodic table (which it shares with Zn, Cd and Hg). It is very volatile and forms a metallic bond with a gold surface. An experiment has scrutinized two atoms of element 112, finding that it is very volatile and forms a metallic bond with a gold surface. These characteristics establish element 112 as a typical element of group 12. The heaviest elements to have been chemically characterized are seaborgium1 (element 106), bohrium2 (element 107) and hassium3 (element 108). All three behave according to their respective positions in groups 6, 7 and 8 of the periodic table, which arranges elements according to their outermost electrons and hence their chemical properties. However, the chemical characterization results are not trivial: relativistic effects on the electronic structure of the heaviest elements can strongly influence chemical properties4,5,6. The next heavy element targeted for chemical characterization is element 112; its closed-shell electronic structure with a filled outer s orbital suggests that it may be particularly susceptible to strong deviations from the chemical property trends expected within group 12. Indeed, first experiments concluded that element 112 does not behave like its lighter homologue mercury7,8,9. However, the production and identification methods10,11 used cast doubt on the validity of this result. Here we report a more reliable chemical characterization of element 112, involving the production of two atoms of 283112 through the alpha decay of the short-lived 287114 (which itself forms in the nuclear fusion reaction12 of 48Ca with 242Pu) and the adsorption of the two atoms on a gold surface. By directly comparing the adsorption characteristics of 283112 to that of mercury and the noble gas radon, we find that element 112 is very volatile and, unlike radon, reveals a metallic interaction with the gold surface. These adsorption characteristics establish element 112 as a typical element of group 12, and its successful production unambiguously establishes the approach to the island of stability of superheavy elements through 48Ca-induced nuclear fusion reactions with actinides.

Summary We present results of the second experiment on the chemical identification of element 112. Similar to the first test in 2000, we aimed at the production of the spontaneously fissioning 283112 nuclei with T 1/2≈3min. A natU3O8 (with some Nd) target, 2mg of U/cm2 thick, was bombarded with 233-MeV 48Ca ions (the energy in the middle of the target layer). The nuclei recoiling from the target were thermalized in flowing helium. The target chamber was connected through a 25m long capillary to detectors of α-particles and fission fragments. All the equipment and detectors were kept at ambient temperature. According to the test experiments, of all the heavy elements produced in the bombardment, only Hg, Rn and At could be transported to the detectors. The first detecting device was similar to that used earlier – an assembly of 8 pairs of PIPS detectors coated with gold. Here one would observe the decay of element 112 atoms if they like Hg adsorbed on gold. The atoms which were not retained and freely passed through the PIPS detectors entered a new, flow-through ionization chamber, 5000 cm3 in volume, optimized for detecting fission fragments. The PIPS detectors and the ionization chamber were placed inside a large assembly of 3He – filled neutron counters to detect prompt neutrons from the fission events. In 22.5 days, a beam dose of 2.8×1018 ions was accumulated. More than 95 of the simultaneously produced α-active 185Hg (T 1/2=49 s) were found deposited already on the first pair of PIPS detectors; meanwhile, all the PIPSs did not detect any fission event. In the ionization chamber, eight fission events were observed in coincidence with neutron counts while the expected background was insignificant. Hence, the spontaneous fissions of the volatile activity can be conclusively attributed to the decay of element 112 produced in the fusion reaction 48Ca+ 238U, and formerly observed in Dubna physical experiments. Evaluation of the experimental data in terms of the adsorption enthalpies indicates much weaker interaction of element 112 with Au than that of Hg. One can conclude that in the given chemical environment, element 112 behaves like Rn rather than like Hg. The formation cross section of 283112 estimated from the data amounts to several pb. The experiments were carried out at the Flerov Laboratory of Nuclear Reactions at JINR in November–December 2001.

The physicochemical and technological properties of an improved modification of soda ash from nepheline material and its effect on batch preparation and silicate and glass formation and on the properties of glass are considered. It is established that the improved modification of soda with respect to its physicochemical and technologies properties and storage behavior belongs to the “heavyweight” category, is a promising alkali-bearing material, and can be recommended for effective application in the production of glass containers and household and sheet glass, including decorative float glass with special properties.

The structure of 6 He is explored with proton elastic and inelastic scattering to the first 2 + excited state (Q =− 1. 8M eV) of 6 He in the inverse kinematics using a 24.5 A MeV 6 He beam. The distorted wave approximation (DWA) with an optical potential obtained by folding an effective nucleon–nucleon (NN) g-matrix with the 6 He density matrix elements as given by a large basis shell model is used to analyse the data. The comparison of predictions with the data confirms the view that 6 He has

The effect of structural disordering on the transport properties of LiNiO2 was studied over wide ranges of temperatures and oxygen pressures.

The stability of heavy nuclides, which tend to decay by α-emission and spontaneous fission, is determined by the structural properties of nuclear matter. Nuclear binding energies and lifetimes increase markedly in the vicinity of closed shells of neutrons or protons (nucleons), corresponding to ‘magic’ numbers of nucleons; these give rise to the most stable (spherical) nuclear shapes in the ground state. For example, with a proton number of Z = 82 and a neutron number of N = 126, the nucleus 208Pb is ‘doubly-magic’ and also exceptionally stable. The next closed neutron shell is expected at N = 184, leading to the prediction of an ‘island of stability’ of superheavy nuclei, for a broad range of isotopes with Z = 104 to 120 (refs 1, 2). The heaviest known nuclei have lifetimes of less than a millisecond, but nuclei near the top of the island of stability are predicted to exist for many years. (In contrast, nuclear matter consisting of about 300 nucleons with no shell structure would undergo fission within about 10−20 seconds.) Calculations3,4,5 indicate that nuclei with N > 168 should already benefit from the stabilizing influence of the closed shell at N = 184. Here we report the synthesis of an isotope containing 114 protons and 173 neutrons, through fusion of intense beams of 48Ca ions with 242Pu targets. The isotope decays by α-emission with a half-life of about five seconds, providing experimental confirmation of the island of stability.

Differential cross sections for the elastic scattering of 6 He exotic nuclei from a gaseous helium target has been measured in a wide angular range in the CM system at a 6 He beam energy of 151 MeV. The large cross-sections obtained at backward angles are discussed in terms of a two-neutron exchange process. The results of DWBA calculations show that this effect can account for the cross sections obtained between 1208 and 1608 assuming the spectroscopic factor to be about 1 for the di-neutron cluster as was predicted by theory for 6 He. q 1998 Published by Elsevier Science B.V. All rights reserved.

Multiple band patterns of DNA repeats in the 20-500-nucleotide range can be detected by digesting genomic DNA with short-cutting restriction endonucleases, followed by end labeling of the restriction fragments and fractionation in nondenaturing polyacrylamide gels. We call such band patterns obtained from genomic DNA "taxonprints" (Fedorov et al. 1992). Here we show that taxonprints for the taxonomic groups studied (mammals, reptiles, fish, insects-altogether more than 50 species) have the following properties: (1) All individuals from the same species have identical taxonprints. (2) Taxonprint bands can be subdivided into those specific for a single species and those specific for groups of closely related species, genera, and even families. (3) Each restriction endonuclease produces unique band patterns; thus, five to ten restriction enzymes (about 100 bands) may be sufficient for a statistical treatment of phylogenetic relationships based on polymorphisms of restriction endinuclease sites. We demonstrate that taxonprint analysis allows one to distinguish closely related species and to establish the degree of similarity among species and among genera. These characteristics make taxonprint analysis a valuable tool for taxonomic and phylogenetic studies.

We have studied the special features and mechanism of combustion of the NiO−Al system under gas pressure. The pressure has been shown to suppress the spread of the initial mixture and to allow the final combustion products to be obtained in a cast form. The chemical composition, combustion limits, and combustion region of cast intermetallides have been found based on the ratio of reactants.

The combustion synthesis (self-propagating high-temperature synthesis, SHS) of a model Cr-CrO3 system is studied both experimentally and theoretically. The system is chemically simple, i.e. it is composed of only two elements, and convenient for combustion and phase formation studies. A new combustion model for a “metal-metal oxide” system and a mathematical model of phase and structure formation are developed. A number of dependencies are determined in the experiments and are described in the combustion model. It is shown that the leading combustion stage is the gas phase oxidation reaction. Different types of microstructures formed from homogeneous melt are revealed. A qualitative agreement between experimental data, theoretical analysis and calculation results is obtained.

For composite materials such as metal-oxide, metal-ceramics, etc., the formation process of grain microstructure has been theoretically considered from the macrokinetic point of view. The interaction (mainly a thermal one) between two immiscible phases during crystallization was studied. Various types of grain-size distribution were found and distinguished. A comparison with an experimental metallographic specimen of a metal-oxide system was made. Self-propagating high-temperature synthesis was used to produce the material ingots. Limits to the use of the model proposed are revealed.

The ${0}^{+}$ ground state of the $^{10}\mathrm{He}$ nucleus produced in the $^{3}\mathrm{H}(^{8}\mathrm{He},p)^{10}\mathrm{He}$ reaction was found at about $2.1\ifmmode\pm\else\textpm\fi{}0.2\text{ }\text{ }\mathrm{MeV}$ ($\ensuremath{\Gamma}\ensuremath{\sim}2\text{ }\text{ }\mathrm{MeV}$) above the three-body $^{8}\mathrm{He}+n+n$ breakup threshold. Angular correlations observed for $^{10}\mathrm{He}$ decay products show prominent interference patterns allowing us to draw conclusions about the structure of low-energy excited states. We interpret the observed correlations as a coherent superposition of a broad ${1}^{\ensuremath{-}}$ state having a maximum at energy 4--6 MeV and a ${2}^{+}$ state above 6 MeV, setting both on top of the ${0}^{+}$ state ``tail.'' This anomalous level ordering indicates that the breakdown of the $N=8$ shell known in $^{12}\mathrm{Be}$ thus extends also to the $^{10}\mathrm{He}$ system.

The maximum temperatures of combustion of the FeO−Al system under gas pressure were determined thermoelectrically by use of different types of thermocouple protection. The possibility of using this method for studying the combustion processes in highly exothermic liquid-phase systems is demonstrated.

By using the 1H(6Li,6Be)n charge-exchange reaction, continuum states in 6Be were populated up to E_t=16 MeV, E_t being the 6Be energy above its three-body decay threshold. In kinematically complete measurements performed by detecting alpha+p+p coincidences, an E_t spectrum of high statistics was obtained, containing approximately ~5x10^6 events. The spectrum provides detailed correlation information about the well-known 0^+ ground state of 6Be at E_t=1.37 MeV and its 2^+ state at E_t=3.05 MeV. Moreover, a broad structure extending from 4 to 16 MeV was observed. It contains negative parity states populated by Delta L=1 angular momentum transfer without other significant contributions. This structure can be interpreted as a novel phenomenon, i.e. the isovector soft dipole mode associated with the 6Li ground state. The population of this mode in the charge-exchange reaction is a dominant phenomenon for this reaction, being responsible for about 60% of the cross section obtained in the measured energy range., 8 pages, 7 figures

The new possibilities of using scattered x-ray radiation in mammology are presented by the example of obtaining the new type of a highly informative breast image, by identifying the distribution of an effective atomic number by dual-energy exposure.

as a result of the Chernobyl nuclear power plant accident. Evaluations and measurements made at the site showed that vertical migration of the radionuclides into the soil in the first months after the accident lowered the dose rate by a factor of 1.5-2.5 [1]. Experimental methods and mathematical models that were developed make it possible to determine the shape of the radionuclide distribution function in the soil [2, 3]. It would be convenient to use analytical relationships, which give a satisfactory approximation to the dose rate, for engineering processing of data on the radionuclide composition of the soil. Calculations of the dose rate from buried sources, which were done using buildup factors for an infinite air space and concrete [4], depend strongly on the initial data and can be off by a factor of 2-3 from Monte Carlo results [5]. An approximate relationship has been suggested [6] which can calculate the effective equivalent dose from sources distributed uniformly in the soil with an error of 10-15%. Here the results of numerical Monte Carlo calculations of the dose rate from a plane source in the soil for photon energies of 0.015-5 MeV are approximated by an analytical relationship obtained by using an expression for the buildup factor in the Berger form. Direct approximation of the numerical modeling results increases the accuracy of the calculation, as compared to a method which uses a buildup factor for an infinite medium. The simple form of the analytical relationship makes it possible to do engineering calculations for various radiation source distributions in the soil. In the problem at hand, a plane monoenergetic isotopic source of photons of energy E.ro extends to infinity along the earth's surface at a depth z s in the soil. The energy was varied from 0.015 to 5 MeV. For energies >_0.1 MeV, the depth was varied from 0 to 30 cm for a characteristic soil density Ps = 1.6 g/cm 3, i.e., z s _< 24-48 cm for 2 _< Os -< 1 g/cm 3. For Evo < 0.1 MeV, z s does not exceed five mean-free paths of photons in the soil, which corresponds to a decrease of the dose rate by roughly 1000 times compared to the dose from a surface source. The chosen ranges of E.ro and z s are sufficient for calculating the dose rate from global fallout and fallout from nuclear power plant ejecta [2, 3, 5, 6]. It was assumed that the detection point was located at a height of z a = 100 cm above the earth's surface. In choosing a Berger-type buildup factor, the absorbed dose rate in air and the effective equivalent dose rate per unit surface activity are determined by the relationship Fp= A {El(r) +

The gain dependence on time of the HCl chemical laser was measured and calculated. Comparison of the calculated and measured results enables one to determine the constant of HCl-HCl deactivation which is found to be within (0.2-9) 10(12) cm(3) mole(-1) sec(-1).

Project of a new in‐flight fragment separator is proposed as a part of the third generation DRIBs facilities in Dubna. As compared to the existing separator ACCULINNA, beam intensity should be increased by a factor 10–15, the beam quality improved and the RIB assortment should broaden considerably at ACCULINNA‐2. Research program and structure are outlined for the new instrument.

Unknown isotope 26S, expected to decay by two-proton (2p) emission, was studied theoretically and was searched experimentally. The structure of this nucleus was examined within the relativistic mean field (RMF) approach. A method for taking into account the many-body structure in the three-body decay calculations was developed. The results of the RMF calculations were used as an input for the three-cluster decay model worked out to study a possible 2p decay branch of this nucleus. The experimental search for 26S was performed in fragmentation reactions of a 50.3 A MeV 32S beam. No events of 26S or 25P (a presumably proton-unstable subsystem of 26S) were observed. Based on the obtained production systematics an upper half-life limit of T_{1/2}640 keV for 26S. Analogous limits for 25P are found as T_{1/2}110 keV. In the case that the one-proton emission is the main branch of the 26S decay a limit Q_{2p}>230 keV would follow for this nucleus. It is likely that 26S resides in the picosecond lifetime range and the further search for this isotope is prospective for the decay-in-flight technique., 15 pages, 7 figures

To determine overall number as well as number of viable cells in continuously incubated cultures of E. carotovora by methods of confocal microscopy and quantitative PCR-analysis.Strain E. carotovora atroseptica SCRI1043 was grown on LB medium to density 2x10(9) CFU/ml. Cells were aggregated by centrifugation and transferred on fresh LB medium, containing alkyloxybenzol, or on the AB medium, which was deficient on phosphorus and carbon. BacLight LIVE/ DEAD kit in combination with confocal laser microscopy as well as quantitative PCR were used for the determination of the number of viable cells.Total number and number of viable cells in cultures on AB medium was high (10() - 10(9) and 10(7) - 10(8) cells/ml respectively) up to 3 - 5 months of cultivation. Though, number of cultivated cells significantly decreased in all variants of the experiment. Number of viable cells in such cultures was several orders greater than genomic copies detected by PCR. Efficacy of DNA amplification increased after dialysis and deproteinization of samples.Loss of cultivation ability when number of viable bacteria is high points to possible switch of E. carotovora cells in non-cultivated state under unfavourable conditions. We assume that it is accompanied by formation of low-molecular components and DNA-bound proteins in cells, which inhibit PCR.