367 research outputs found

    Dynamic Stabilization of Cubic AuZn

    Get PDF
    A recently developed temperature-dependent effective potential method is employed to study the martensitic phase transformation in AuZn. This method is based on ab initio molecular dynamics and allows to obtain finite-temperature lattice vibrational properties. We show that the transversal acoustic TA_2[110] mode associated with the phase transition is stabilized at 300 K. Temperature evolution of single-phonon dynamic structure factor at the wave vector q=1/3[1,1,0], associated with phonon softening and Fermi surface nesting, was also studied

    Hourly average values of solar wing parameters (flow rate and ion temperatures) according to data of measurements of the Venera-9 and Venera-10 automatic interplanetary stations on an Earth-Venus during the period June 1975 - April 1976

    Get PDF
    Four electrostatic analyzers with channel electron multipliers as detectors were used to measure solar wind ionic flow. The axes of the fields of vision of two of these analyzers were directed along the axis of the automatic interplanetary station, oriented towards the Sun, while the other two were turned in one plane at angles of +15 deg and -15 deg. The full hemisphere of the angular diagram of each analyzer was approximately 5 deg. The energetic resolution was approximately 6%, and the geometric energy was 0.002 sq cm ave. keV. Each analyzer covered an energetic range of approximately 10 in eight energetic intervals. Spectral distributions were processed in order to obtain the velocity and temperature of the protons. Tabular data show the hour interval (universal time) and the average solar wind velocity in kilometers per second

    Evaluation of commercial traits in the accessions of Medicago sativa L. from Asia Minor

    Get PDF
    Background. One of the main tasks of the present-day breeding practice is the development of high-yielding intensive-type fodder crop cultivars for indoor feeding of livestock. Alfalfa, as a productive and high-protein crop, deserves special attention. An offer of new breeding sources would enable breeders to broaden the diversity of alfalfa cultivars. Objective. The present study involved 65 local varieties and wild accessions of alfalfa from Turkey preserved in the VIR collection. Material and methods. Yekaterinino Experiment Station of VIR (Tambov Province) was chosen as the research site. Evaluation of the alfalfa collection was carried out in 2015–2017, using the methods developed at VIR for fodder crop research targeted at such traits as green biomass yield, seed productivity, and leafiness. The cultivar ‘Marusinskaya 425’ was used as the reference. Results and conclusions. In 2015, four accessions were identified as promising for their green matter yield and seed productivity: local varieties k-3373 and k-3378 from Konya Province, k-5992 from Isparta Province, and k-6116 from Sivas Province. In 2016, three accessions exceeded the reference in the yield of green matter, and three accessions had higher seed productivity. Eight accessions surpassed the reference in leafiness. In 2017, only one accession, k-6009 (Kayseri Province), significantly exceeded the reference in green matter yield. Nine accessions were selected for their high seed yield. The maximum seed productivity was observed in the accession k-3379 (Konya). Leafiness was notably higher than the reference’s in 15 accessions. The average for three years shows that none of the accessions credibly surpassed the reference in green matter yield. Four accessions had higher seed productivity than the reference. According to the three-year average, 11 accessions exceeded the reference in leafiness. All in all, in the three years of study, the accessions k-3373, k-3378 and k-3379 (Konya) were selected for high green matter yield and seed productivity. High seed productivity and leafiness, with satisfactory green matter yield, were registered in the accession k-5992 (Isparta). The accession k-6009 (Kayseri) significantly exceeded the reference in green matter yield, but demonstrated low seed productivity and poor leafiness. The place of origin for the identified local accessions had been Central Anatolia, with its continental climate. These accessions are valuable breeding sources with noteworthy commercial traits. Alfalfa from Asia Minor can be recommended for use in breeding practice, targeted at the development of new high-yielding intensive-type cultivars

    Gastric Microbiota and Morphological Changes of the Gastroduodenal Tract Associated with Helicobacter Pylori Infection

    Get PDF
    © 2016, Springer Science+Business Media New York.Investigation of the microbiota at morphological changes of a gastrointestinal tract. One hundred four patients were examined by cytologic, bacteriological methods, and mass-spectrometry techniques. Studying of the microbial association of stomach has demonstrated the mixed microflora presented by Helicobacter pylori, cocci, fungi Candida, rods, and protozoa. Bacteria of the following species were found: Actinomyces, Arthrobacter, Bacillus, Corynebacterium, Lactobacillus, Neisseria, Pseudomonas, Rothia, Staphylococcus, Streptococcus, and Streptomyces. The microbial flora of esophageal samples was less various (opportunistic bacteria Neisseria, Gemella, and Rothia mucilaginosa were revealed). In group of Helicobacter-positive patients, bacteria were found in fungi Candida, Colletotrichum, and bacterias Thauera and Mycoplasma, while in H.pylori-negative patients, samples have more different species. Intensity of morphological changes (the atrophy, the intestinal metaplasia, and the dysplasia) correlated with a frequency of detection of H. pylori and eukaryotic microbiota (fungi Candida and protozoa)

    All-thermal switching of amorphous Gd-Fe alloys: Analysis of structural properties and magnetization dynamics

    Get PDF
    In recent years, there has been an intense interest in understanding the microscopic mechanism of thermally induced magnetization switching driven by a femtosecond laser pulse. Most of the effort has been dedicated to periodic crystalline structures while the amorphous counterparts have been less studied. By using a multiscale approach, i.e. first-principles density functional theory combined with atomistic spin dynamics, we report here on the very intricate structural and magnetic nature of amorphous Gd-Fe alloys for a wide range of Gd and Fe atomic concentrations at the nanoscale level. Both structural and dynamical properties of Gd-Fe alloys reported in this work are in good agreement with previous experiments. We calculated the dynamic behavior of homogeneous and inhomogeneous amorphous Gd-Fe alloys and their response under the influence of a femtosecond laser pulse. In the homogeneous sample, the Fe sublattice switches its magnetization before the Gd one. However, the temporal sequence of the switching of the two sublattices is reversed in the inhomogeneous sample. We propose a possible explanation based on a mechanism driven by a combination of the Dzyaloshiskii-Moriya interaction and exchange frustration, modeled by an antiferromagnetic second-neighbour exchange interaction between Gd atoms in the Gd-rich region. We also report on the influence of laser fluence and damping effects in the all-thermal switching

    4.各部門の活動内容 理学療法科

    Get PDF
    © 2016, Springer Science+Business Media New York.Investigation of the microbiota at morphological changes of a gastrointestinal tract. One hundred four patients were examined by cytologic, bacteriological methods, and mass-spectrometry techniques. Studying of the microbial association of stomach has demonstrated the mixed microflora presented by Helicobacter pylori, cocci, fungi Candida, rods, and protozoa. Bacteria of the following species were found: Actinomyces, Arthrobacter, Bacillus, Corynebacterium, Lactobacillus, Neisseria, Pseudomonas, Rothia, Staphylococcus, Streptococcus, and Streptomyces. The microbial flora of esophageal samples was less various (opportunistic bacteria Neisseria, Gemella, and Rothia mucilaginosa were revealed). In group of Helicobacter-positive patients, bacteria were found in fungi Candida, Colletotrichum, and bacterias Thauera and Mycoplasma, while in H.pylori-negative patients, samples have more different species. Intensity of morphological changes (the atrophy, the intestinal metaplasia, and the dysplasia) correlated with a frequency of detection of H. pylori and eukaryotic microbiota (fungi Candida and protozoa)

    Dilution of the magnetic lattice in the Kitaev candidate α\alpha-RuCl3_3 by Rh3+^{3+} doping

    Get PDF
    Magnetic dilution of a well-established Kitaev candidate system is realized in the substitutional Ru1x_{1-x}Rhx_xCl3_3 series (x=0.020.6x = 0.02-0.6). Optimized syntheses protocols yield uniformly-doped single crystals and polycrystalline powders that are isostructural to the parental α\alpha-RuCl3_3 as per X-ray diffraction. The Rh content xx is accurately determined by the quantitative energy-dispersive X-ray spectroscopy technique with standards. We determine the magnetic phase diagram of Ru1x_{1-x}Rhx_xCl3_3 for in-plane magnetic fields from magnetization and specific-heat measurements as a function of xx and stacking periodicity, and identify the suppression of the magnetic order at x0.2x \approx 0.2 towards a disordered phase, which does not show any clear signature of freezing into a spin glass. Comparing with previous studies on the substitution series Ru1x_{1-x}Irx_xCl3_3, we propose that chemical pressure would contribute to the suppression of magnetic order especially in Ru1x_{1-x}Irx_xCl3_3 and that the zigzag magnetic ground state appears to be relatively robust with respect to the dilution of the Kitaev--Γ\Gamma--Heisenberg magnetic lattice. We also discovered a slight dependence of the magnetic properties on thermal cycling, which would be due to an incomplete structural transition

    A "saddle-node" bifurcation scenario for birth or destruction of a Smale-Williams solenoid

    Full text link
    Formation or destruction of hyperbolic chaotic attractor under parameter variation is considered with an example represented by Smale--Williams solenoid in stroboscopic Poincar\'{e} map of two alternately excited non-autonomous van der Pol oscillators. The transition occupies a narrow but finite parameter interval and progresses in such way that periodic orbits constituting a "skeleton" of the attractor undergo saddle-node bifurcation events involving partner orbits from the attractor and from a non-attracting invariant set, which forms together with its stable manifold a basin boundary of the attractor.Comment: 7 pages, 7 figures, 1 tabl

    Two-dimensional ferromagnetic extension of a topological insulator

    Full text link
    Inducing a magnetic gap at the Dirac point of the topological surface state (TSS) in a 3D topological insulator (TI) is a route to dissipationless charge and spin currents. Ideally, magnetic order is present only at the surface and not in the bulk, e.g. through proximity of a ferromagnetic (FM) layer. However, such a proximity-induced Dirac mass gap has not been observed, likely due to insufficient overlap of TSS and the FM subsystem. Here, we take a different approach, namely FM extension, using a thin film of the 3D TI Bi2_2Te3_3, interfaced with a monolayer of the lattice-matched van der Waals ferromagnet MnBi2_2Te4_4. Robust 2D ferromagnetism with out-of-plane anisotropy and a critical temperature of Tc\text{T}_\text{c}\approx~15 K is demonstrated by X-ray magnetic dichroism and electrical transport measurements. Using angle-resolved photoelectron spectroscopy, we observe the opening of a sizable magnetic gap in the 2D FM phase, while the surface remains gapless in the paramagnetic phase above Tc_c. This sizable gap indicates a relocation of the TSS to the FM ordered Mn moments near the surface, which leads to a large mutual overlap.Comment: 6 pages, 3 figure
    corecore