The microstructure and morphology of superconducting Nb3Sn layers in multifilamentary composites differing in the fabrication route (bronze technology and internal-tin method), the shape of Nb ...filaments (continuous, coupled and tubular) and in the mode of Ti doping (doping of bronze matrix or Nb filaments) have been studied. Significant factors determining critical current density of these wires are the average grain sizes and the fraction of equiaxed grains in the superconducting layers. The minimal grain sizes are characteristic of the composites with tubular Nb filaments, whereas the maximal fraction of equiaxed grains is obtained in the internal-tin wires.
•Jc of Nb3Sn–based strands depends on Nb3Sn grain size and fraction of equiaxed grains.•The min Nb3Sn grain size is observed in bronze-route wires with tubular Nb filaments.•The maximal fraction of equiaxed grains (96%) is obtained in the internal-tin wires.
Justification of impregnation modes for wood Gazizov, A M; Samosenko, E G; Popova, E V
Journal of physics. Conference series,
07/2021, Letnik:
1967, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract
One of the most significant disadvantages of wood materials is increased combustibility. Therefore, the problem of reducing the combustibility of wood materials is relevant. The article ...describes an experimental study of impregnation of wood using biopiren MIG-09, which is a hybrid composition on a salt basis with the addition of functional substances of non-salt nature, at different temperature regimes. Two stages of the study were chosen for the experiment. The optimum temperature regimes for different methods of applying the composition to increase the fire resistance of wood were established experimentally. Also fire tests were carried out to analyze the degree of penetration of the solution.
The research is based on the results of local monitoring in 1990-2018 on reference plots of agricultural lands and archival materials of a large-scale agrochemical survey. The purpose of the research ...is to identify patterns of change in the humus content of arable soils of the forest-steppe in the Omsk region after prolonged use in agriculture. The objects of research were the soils of the forest-steppe zone of the Omsk Region: ordinary chernozem low-power low-humus heavy loamy soil; meadow-chernozem medium-thick medium-humus heavy loamy soil; solonetz meadow chernozemic deep low humus clay soil. The largest area on the last round of agrochemical survey of 1194.3 thousand ha (58.9%) has an average humus content (4.1-6.0%), it increased significantly from 784.5 thousand ha (38.7%). The increased and high (> 6%) humus content significantly decreased over the study period by 416.5 thousand ha from 1118.5 (55.1%) to 702.0 thousand ha (34.6% of the surveyed area). The weighted average humus content over 28 years has changed: from 6.2 to 6.0% in the northern forest-steppe, from 6.0 to 5.3% in the southern forest-steppe, on average it is by 0.5%. A tendency toward a decrease in the humus content of soils remains in the soils of the Omsk Priirtyshye region. The main reason for this is both the ongoing water and wind erosion of soils, and the very low level of organic fertilizers use. The authors revealed the gradual decrease in the content of humus in ordinary chernozems and meadow chernozem soils. There was a stable humus content in the arable horizon of the solonetzes of deep meadow-chernozem soils.
The microstructure and thermal stability of multifiber in situ Cu-18Nb composites with a true strain (
e
) of 10.2 and 12.5 have been studied by the methods of scanning and transmission electron ...microscopy and X-ray diffraction analysis. It has been established that niobium dendrites in the copper matrix acquire the shape of ribbons with thicknesses of less than 100 nm under strong plastic deformation. As the strain grows, the thickness of niobium ribbons decreases, and the degree of axial texture 〈110〉Nb║〈111〉Cu║DA (drawing axes) and the macrostresses in the crystal lattice of niobium increase. Interplanar distances between adjacent {110}Nb planes are stretched in the longitudinal section of the composites and reduced in their transversal section under the action of macrostresses. It has been shown that, as a result of the annealing of these composites, niobium fibers sustain coagulation, which begins at 300°C, actively develops with increasing temperature, and leads to the appreciable softening of a composite at 700°C. The softening of a composite after the annealing is accompanied by the relaxation of macrostresses in niobium and the recovery of its unit cell parameters to standard values.
Suspension cell culture of camel’s thorn
Alhagi persarum
Boiss. et Buhse was produced for the first time and its characteristics were determined under different growing conditions (flasks and bubble ...bioreactors with useful volume of 15 L). The obtained culture was notable for an intense growth (accumulation of dry biomass of 15–20 g/L, growth index of 11–16, and specific growth rate of 0.15 ± 0.01 d
–1
), with growth characteristics in bioreactors close to parameters observed in flasks. Qualitative composition of secondary metabolites in biomass of this cell culture grown in flasks was preliminarily examined by means of ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-ESI-MS). Isoflavones from different structural groups were detected: free isoflavones (an isomer of afrormosin), glycosides of isoflavones (glycosides of calycosin and formononetin), and acylated glycosides of isoflavones (malonyl glycosides of calycosin, formononetin, genistein, and the isomer of afrormosin). Extracts from biomass of
A. рersarum
suspension cell culture grown in flasks were tested for antimicrobial activity.
Staphylococcus aureus
АТСС 25923 and
Pseudomonas aeruginosa
АТСС 27853 were used as test cultures. Extracts showed a specific antimicrobial activity in respect to
S. aureus
but were inactive to
P. aeruginosa
. Thus, the obtained cell culture of
A. persarum
is a promising object for further examination with a potential of using as an alternative raw material and a source of biologically active compounds characteristic of this species.
A new variety population of meadow clover GPF-49-3, promising for use in agricultural production in the northern regions of the European part of the Russian Federation (RF), has been created in the ...Federal Agricultural Research Center of the North-East named N. V. Rudnitsky. It is characterized by early periods of mowing and harvesting ripeness: the duration of the growing season from spring regrowth to the flowering phase of the first mowing is 56-72 days, from the first to the second mowing is 39-56 days, until the seeds ripen 103-115 days. According to the results of the study and evaluation in several cycles of competitive and environmental tests (2009–2021) in the conditions of the Kirov region, GPF-49-3 has shown advantages over the zoned standard cultivar (st.) ʻDymkovskyʼ in a number of productive features and adaptive qualities: it is characterized by winter hardiness, tolerance to drought, high productivity and its potential – harvesting of green mass up to 88.3 t/ha, dry matter up to 20.5 t/ha, crude protein up to 2.5 t/ha, seed yield up to 5.3 c/ha. The features of the GPF-49-3 cultivar population are significantly high in comparison with the standard forage productivity of the second year of use (y.u.) – 28.7 t/ha of green mass, 7.8 t/ha of dry matter at the level of standard ʻDymkovskyʼ cultivar – 23.4 and 6.2 t/ha, respectively (LSD05 = 4.5 and 0.8 t/ha), and genetically determined resistance to root rot. A correlation (r) of average strength was found between the intensity of root rot development in 1 y.u. and plant productivity indicators in 2 y.u.: green mass (-0.43), dry matter (-0.50), protein collection (-0.58.), indicating that the herbage with a lower degree of root damage before overwintering is more productive for the next year of use. The obtained research results made it possible to make a decision on the transfer of the GPF-49-3 cultivar population to the state cultivar testing in 2021, as a cultivar of meadow clover ʻMalakhitʼ.
A comparative analysis of four isolated edible dormouse populations inhabiting the Greater Caucasus (Western Caucasus, Eastern Caucasus, and Transcaucasia) and the Lankaran district in southern ...Azerbaijan was made on the basis of 15 morphometric skull characters. The craniometric differences between the Lankaran population and the three Greater Caucasus populations significantly exceed the morphometric variations between individual Caucasian populations and correlate with the divergence time of these groups. Edible dormice from the Lankaran population are distinguished by a shorter
bulla tympani
, narrower interorbital septum, longer maxillary tooth row, narrower neurocranium, and distinct structures and relative widths of the hind parts of the nasal and premaxillary bones (
ossa nasalia
and
processus frontalis ossis praemaxillaris
, respectively). These differences are statistically significant and can be used to diagnose edible dormice belonging to this group. The obtained data support the hypothesis that
Glis persicus
(Erxleben 1777) is an independent species. The morphological differences between the Caucasian edible dormouse populations are much less pronounced, but still statistically significant. Edible dormice inhabiting the southern macroslope of the Caucasus Ridge (Transcaucasia) differ significantly from both groups inhabiting the northern macroslope in the linear skull dimensions. Compared to the two other Caucasian edible dormouse populations, the Western Caucasus sample features a shorter
bulla tympani
relative to CBL and a shorter maxillary tooth row. The Eastern Caucasus and Transcaucasian samples differ to the greatest extent in the entire set of morphometric characters. The Western Caucasus population occupies an intermediate position. Paleogeographical data indicate that edible dormouse populations inhabiting the broad-leaved Hyrcanian Forest in Iran and southern Azerbaijan could not have become isolated before the Piacenzian stage of the Late Pliocene (i.e., 3.6 to 2.6 million years ago). This date is close to the minimum TMRCA (time to the most recent common ancestor) of modern edible dormice computed based on molecular evidence. The most recent edible dormouse colonization wave came to the Greater Caucasus from Europe; this is how individuals featuring cytochrome
b
(
cytb
) haplotypes of the young (so-called European) lineage invaded the region. The low haplotypic variability of this gene across the wide range of populations of the European lineage indicates that the Caucasus could not have been colonized before the Upper Pleistocene. The maximum divergence time does not exceed 0.13 million years for all edible dormouse populations inhabiting the Caucasus.
The article presents the results of many years of research (2011-2021) on determining the quality of Hungarian clover (Trifolium pannonicum Jacq.) seeds of Snezhok variety obtained in the conditions ...of Kirov region (North-East of the European part of Russia). The weight of 1000 seeds averaged 4.16 g with changes over the years from 3.83 to 4.60 g and depended on the amount of precipitation (r = 0.71), the hydrothermal coefficient during the flowering period of grass stands (r = 0.69), average daily and daytime air temperatures during the "flowering-the beginning of maturation" period (r = -0.70). On average, the length of the seeds was 2.45 mm, width – 1.93 mm; thickness – 1.40 mm. According to the ratio of these parameters, the seeds had an ovoid and ellipsoid (elongated) shape. The size of the seed material (integral indicator) did not exceed 2.0 mm. In years with greater moisture availability (98-189 % to the norm) large seeds were formed (from 1.92 to 2.00 mm), with insufficient moisture (64-81 %) ‒ small seeds (1.78 mm). According to the initial germination indicators, all seed material met the requirements of GOST R 52325-2005 and was classified as "original seeds". Germination and germinating energy were 86.7-99.5 and 80.0-97.0 %, respectively, they depended on the average daily air temperature during the "budding-seed ripening" period (r = 0.66 and 0.68) and remained at a high level for the first three to four years of storage. The seed material had mainly a low content of hard seeds (1.5-7.0 %). In some years, the "hard-seeding" of freshly harvested seeds reached 20.0-36.0%, however, after the post-harvest ripening period, it significantly decreased. The freshly harvested seeds had a yellow color, which gradually changed to beige-brown or brown-beige during storage. Regression analysis showed a strong relationship between the color of seeds of different storage periods and germination rates. The presence of a large number of yellow seeds in the batch indicated to their high germinating energy (r = 0.98) and germination (r = 0.95). the predominant content of brown seeds indicated to the loss of seed sowing qualities (r = -0.94 and r = -0.91, respectively).
Among the grain forage crops in the Russian Federation, barley ranks first in terms of multi-use and gross yields. However, the current level of grain production of this crop does not fully meet the ...needs of the livestock and food industries. Winter barley varieties are currently approved for use in the North Caucasus, Middle Volga and Nizhnevolsk regions of the Russian Federation, where its yield is 1.5–2 times higher than that of spring barley. According to the trait ‘productivity’ barley varieties of various breeding institutions have quite significant fluctuations in the regions of their cultivation, and therefore inter-station tests are carried out to determine their response. The best ones are further used in various breeding projects. The purpose of the current paper was to analyze the trait ‘productivity’ and its components and grain quality among present local and foreign winter barley varieties, in order to use the identified ones in crossings parental forms. The monitoring of varieties was carried out on the experimental plot of the Federal State Budgetary Scientific Institution “ARC «Donskoy” (2017–2019). The subjects of the study were winter barley varieties (29 samples) of local and foreign origin. Based on the results of a system analysis, there has been identified a number of varieties that have the necessary combinations of traits important for breeding, such as:
– high productivity (the multi-row varieties ‘Marusya’, ‘Vivat’, ‘Foks 1’, ‘Erema’, ‘Artel’, ‘Dostoyny’ (Russia), ‘KWS-Scala’ (Germany), ‘Capten’ (France));
– coarse-grained (the multi-row lines ‘KWS-117’, ‘KWS-234’, ‘KWS-History’ (Germany) and the two-row varieties ‘Explorer 3’, ‘Explorer 4’, ‘Explorer 5’, ‘Explorer 7’, ‘Explorer 3/2’, ‘Explorer 4/2’, ‘Bronskyli’ (France) with more than 50 g);
– head density per 1 m
2
when harvesting (the two-row varieties ‘KWS-History’ with 704 pcs/m
2
, ‘KWS-117’ with 710 pcs/m
2
(Germany), ‘Explorer 8’ with 739 pcs/m
2
, ‘Explorer 3/2’ with 759 pieces/m
2
, ‘Wintwalt’ with 847 pieces/m
2
(France));
– number of grains per head (the multi-row varieties ‘Marusya’ with 57.9 pcs, ‘Andryusha’ with 55.8 pcs (Russia), ‘Capten’ with 55.6 pcs (France) and two-row varieties ‘Explorer 3’ with 26.0 pcs., ‘Explorer 5’ with 25.9 pcs., ‘Bronskyli’ with 25.8 pcs (France);
– stable protein percentage in grain less than 11 % (the two-row varieties ‘KWS-History’ with 10.3 %, ‘KWS-234’ with 10.7 % (Germany) and ‘Explorer 3/2’ with 10.3 % (France).
In the present study, the Nb3Sn-based multifilamentary wires with coupled Nb filaments have been investigated by SEM and TEM after various regimes of intermediate annealing including short ...high-temperature heat treatments and after two-staged diffusion annealing. The formation of some amount of pre-reacted Nb3Sn layers has been revealed in all the wires studied, and their amount depends on the wire diameter, temperature and duration of the intermediate heat treatment. The structure of final diffusion layers is also affected by the regimes of these preliminary treatments. This research enables the revealing of the optimal heat treatment schedules for the formation of most perfect nanocrystalline structure of superconducting layers ensuring the highest critical current densities.
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