Phase Composition and Defect Substructure of Strengthening Layer Surfaced on Low Alloyed Steel

The microstructure and microhardness distribution in surface of low carbon Hardox 450 steel coated with alloyed powder wires of different chemical compositions are studied. It is shown that the microhardness of 6-8 mm thickness surfaced layer exceeds that of base metal by more than 2 times. The increased mechanical properties of surfaced layer are caused by the submicro and nanoscale dispersed martensite, containing the niobium carbides Nb2C, NbC and iron borides Fe2B. In the bulk plates a dislocation substructure of the net-like type with scalar islocation density of 10^11 cm^-2 is observed. The layer surfaced with the wire containing B possesses the highest hardness. The possible mechanisms of niobium and boron carbides formation in surfacing are discusse

Sym28, a gene controlling stem architecture and nodule number, is localized on linkage group V

Garden pea (Pisum sativum L.) represents one of the most important models for studying plant developmental genetics. This species serves as a model object for most investigations on the genetic control of formation of compound inflorescence, compound leaf and of symbiotic interaction with nitrogen-fixing bacteria (nodulation). The latter phenomenon is typical for most legumes and is of significant theoretical and practical interest. By now, multiple genes involved in the genetic control of nodulation have been identified (for review see (2)). One of the key processes in plant development is the regulation of stem apical meristem (SAM) activity. Studies on the model plant Arabidopsis thaliana (L.) Heynh. (Brassicaceae) demonstrated that equilibrium between SAM proliferation and keeping its volume stable is reached via the CLAVATA-WUSCHEL regulatory feedback loop. Expression of the gene WUSCHEL (WUS) maintains the meristematic condition of cells and activates expression of the CLAVATA (CLVI, CLV2 and CLV3) gene family. CLV proteins negatively regulate expression of WUS thus limiting its expression pool (14). Mutations in CLV genes lead to abnormal enlargement of the WUS-expressing zone resulting in flower and stem fasciation. Genes of the FASCIATA (FAS! and FAS2) family also serve as negative regulators of WUS (5)

A gene for stem fasciation is localized on linkage group III

Fasciation is one of the most widespread abnormalities of higher plant development. An understanding of the inheritance of the trait is very important, not only for theoretical purposes dealing with genetic control of meristem activity but also for practical use. Stem and fruit fasciation is used as an agriculturally valuable trait in selection of many species including pea (Pisum sativum L). The peculiarities of genetic control of fasciation in pea are still being discussed

Fatigue life of silumin treated with a high-intensity pulsed electron beam

The regularities of the formation of the structure of silumin irradiated with a high-intensity electron beam in different modes are revealed using optical and scanning electron microscopy. The optimum irradiation mode that allows one to increase the fatigue life of this material by a factor of up to 3.5 is determined. The probable causes of the observed effect are investigated

Fatigue variation of surface properties of silumin subjected to electron-beam treatment

The analysis of structure-phase states modification of silumin subjected to electron beam treatment with the following fatigue loading up to the failure is carried out by methods of transmission electron diffraction microscopy. The tribology and strength properties of silumin surface after electron beam treatment and fatigue tests are studied and hardness decrease, wear coefficient and friction coefficient increase with the growth of cycles number are revealed. The possible reasons of the tribology and strength properties of silumin surface layers decrease are discussed

Improvement of radiopurity level of enriched 116^{116}CdWO4_4 and ZnWO4_4 crystal scintillators by recrystallization

As low as possible radioactive contamination of a detector plays a crucial role to improve sensitivity of a double beta decay experiment. The radioactive contamination of a sample of $^{116}$CdWO$_4$ crystal scintillator by thorium was reduced by a factor $\approx 10$, down to the level 0.01 mBq/kg ($^{228}$Th), by exploiting the recrystallization procedure. The total alpha activity of uranium and thorium daughters was reduced by a factor $\approx 3$, down to 1.6 mBq/kg. No change in the specific activity (the total $\alpha$ activity and $^{228}$Th) was observed in a sample of ZnWO$_4$ crystal produced by recrystallization after removing $\approx 0.4$ mm surface layer of the crystal.Comment: 14 pages, 5 figures and 2 table

First test of an enriched 116^{116}CdWO4_4 scintillating bolometer for neutrinoless double-beta-decay searches

For the first time, a cadmium tungstate crystal scintillator enriched in $^{116}$Cd has been succesfully tested as a scintillating bolometer. The measurement was performed above ground at a temperature of 18 mK. The crystal mass was 34.5 g and the enrichment level ~82 %. Despite a substantial pile-up effect due to above-ground operation, the detector demonstrated a high energy resolution (2-7 keV FWHM in 0.2-2.6 MeV $\gamma$ energy range), a powerful particle identification capability and a high level of internal radiopurity. These results prove that cadmium tungstate is an extremely promising detector material for a next-generation neutrinoless double-beta decay bolometric experiment, like that proposed in the CUPID project (CUORE Upgrade with Particle IDentification)

Nucleon-nucleon interaction in the JJ-matrix inverse scattering approach and few-nucleon systems

The nucleon-nucleon interaction is constructed by means of the $J$-matrix version of inverse scattering theory. Ambiguities of the interaction are eliminated by postulating tridiagonal and quasi-tridiagonal forms of the potential matrix in the oscillator basis in uncoupled and coupled waves, respectively. The obtained interaction is very accurate in reproducing the $NN$ scattering data and deuteron properties. The interaction is used in the no-core shell model calculations of $^3$H and $^4$He nuclei. The resulting binding energies of $^3$H and $^4$He are very close to experimental values.Comment: Text is revised, new figures and references adde

Complex therapy against toxascariosis of caged silver foxes

The purpose of the research is evaluating the efficacy of complex therapy using dironet, lactobifadol and keratin food supplement (DLK) against toxascariosis of the arctic fox.Materials and methods. To determine the helminth fauna in the conditions of Vyatka Fur Breeding Farm, 61 females silver fox and 55 females voilevoy arctic fox were used as study objects. To conduct complex therapy against toxascariosis, the study object was 24 females culled from the breeding herd, spontaneously infected with toxascariosis and being clinically healthy. The morphological and biochemical blood parameters in female foxes were determined before and after dehelminthization, and control weighing of animals from experimental groups was carried out before and after the experiment.Results and discussion. Of the studied 116 fur-bearing animals, 26 (22.4%) were infected with Toxascaris leonina. Infection rate of Toxascaris sp. in silver fox females aged 5–7 years was 42.6% when 7-9 eggs were found in one microscope field (magnification 7 × 9). Infection with Toxascaris sp. affects on the body weight of infected animals. The females silver fox from the second experimental group infected with Toxascaris sp., which were not treated, had an average live weight of 1.3 kg less (16.6%) as compared to the control. The complex therapy with the DLK treatment-and-prophylactic complex contributed to the improved metabolic processes and digestion. The applicability of the DLK treatment-and-prophylactic complex for therapy against toxascariosis was proved