312 research outputs found

    VALEOLOGICAL ASPECTS OF HEALTHY LIFESTYLE OF YOUNG GENERATION

    Get PDF
    This article analyses knowledge of students in the process of testing of students Urgench State University, while learning Valeology and Physical training subject

    Metal-ceramic composite development based on its modelling results

    Get PDF
    The modeling (and its experimental verification) of packing and deformation of the composites consisted of aluminum-magnesium alloy AMg6, B[4]C powder and W nano-powder has been performed. The powder compositions were determined using discrete element modeling of the composite particles packing based on the particle size distribution functions of real powders. The models of maximum mixture packing densities have been rendered

    Evidence for competition between the superconducting and the pseudogap state in (BiPb)_2(SrLa)_2CuO_{6+\delta} from muon-spin rotation experiments

    Full text link
    The in-plane magnetic penetration depth \lambda_{ab} in optimally doped (BiPb)_2(SrLa)_2CuO_{6+\delta} (OP Bi2201) was studied by means of muon-spin rotation. The measurements of \lambda_{ab}^{-2}(T) are inconsistent with a simple model of a d-wave order parameter and a uniform quasiparticle weight around the Fermi surface. The data are well described assuming the angular gap symmetry obtained in ARPES experiments [Phys. Rev. Lett {\bf 98}, 267004 (2007)], where it was shown that the superconducting gap in OP Bi2201 exists only in segments of the Fermi surface near the nodes. We find that the remaining parts of the Fermi surface, which are strongly affected by the pseudogap state, do not contribute significantly to the superconducting condensate. Our data provide evidence that high temperature superconductivity and pseudogap behavior in cuprates are competing phenomena.Comment: 5 pages, 3 figure

    Zero-field superfluid density in d-wave superconductor evaluated from the results of muon-spin-rotation experiments in the mixed state

    Full text link
    We report on measurements of the in-plane magnetic penetration \lambda_{ab} in the optimally doped cuprate superconductor (BiPb)_2(SrLa)_2CuO_6+\delta (OP Bi2201) by means of muon-spin rotation (\muSR). We show that in unconventional dd-wave superconductors (like OP Bi2201), \muSR experiments conducted in various magnetic fields allow to evaluate the zero-field magnetic penetration depth \lambda_0, which relates to the zero-field superfluid density in terms of \rho_s\propto\lambda_0^-2.Comment: 4 pages, 5 figure

    Spin-liquid signatures in the quantum critical regime of pressurized CePdAl

    Get PDF
    CePdAl is a prototypical frustrated Kondo lattice with partial long-range order (LRO) at TN=2.7T_\mathrm{N}=2.7 K. Previous bulk experiments under hydrostatic pressure found signatures for a quantum critical regime that extends from pc0.9p_\mathrm{c} \approx 0.9 GPa, where LRO disappears, up to 1.7\sim 1.7 GPa. We employed extensive muon spin relaxation and rotation (μ\muSR) experiments under pressure. The continuous and complete suppression of LRO at pcp_\mathrm{c} is confirmed. Above TN(p)T_\mathrm{N}(p) and beyond pcp_\mathrm{c}, an additional crossover scale T(p)T^\ast(p) characterizes the change from pure to stretched exponential relaxation in zero field. Remarkably T(p)T^\ast(p) agrees with previously determined signatures of entropy accumulation above LRO. This coincidence microscopically evidences fluctuating frustrated spins at TTT\leq T^\ast with spin-liquid behavior. Power-law divergences of the temperature and longitudinal field dependences of the relaxation rate, with time-field scaling, at pressures between pcp_c and 1.7 GPa characterize this regime as quantum critical.Comment: 5 pages, 4 figures and supplemental material (3 pages, 4 figures

    Transients in media with near dipole-dipole interatomic interaction

    Get PDF
    The effect that may be exerted by an interatomic near dipole-dipole interaction upon optical transient processes in dense resonance media is analyzed. The behavior of the macroscopic polarization after a one-pulse excitation of a dense ensemble of two-level atoms is considered. It is shown that the free polarization signal is of oscillatory nature, with the oscillation frequency varying in time and being dependent on the dipole-dipole interaction constant, the intensity and duration of the exciting pulse, and the detuning of its carrier frequency from the resonance. The free polarization signal decay, which depends on the magnitude and sign of the sum of the detuning of the exciting pulse carrier frequency from the resonance and the Lorentz frequency, may obey either a power or an exponential law. The signal decay rate is determined not only by the inhomogeneous broadening, but also by the ratio of the above parameters. The peculiarities of echo-responses under one- or two-pulse excitation conditions are studied

    Evaluation of external fixation device stiffness for rotary osteotomy

    Get PDF
    © Research India Publications. The paper presented the results of strength and stiffness calculation in respect of external fixation device used in the concept of a three-plane spatial correction of proximal femur abnormal orientation taking into account the stage of the disease concerning the localization of degenerative dystrophic process and damage severity. A three-dimensional parametric model of the device was developed and its finite element discretization by four node tetrahedral finite element with a linear approximation and the four node hexagonal finite element with linear approximation. The problem of stress-strain state determination was solved of the structure in the linear formulation on the basis of the finite element method for different values of swivel bracket structure turn. Stress localization zones, the dangerous sections of threaded connections were determined. We obtained the values of maximum shear stress and the stress intensity for various states of construction. On the basis of these data the workloads were determined, the threaded connections of which made 15 Nm by stiffness. The safety margin of the structure by plasticity allows the loads up to 24 Nm. In order to increase the reliability and the hardness of external fixation device the attachment points of pins to rotary brackets were reinforced by locknuts
    corecore