317 research outputs found
VALEOLOGICAL ASPECTS OF HEALTHY LIFESTYLE OF YOUNG GENERATION
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
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
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
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
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
CePdAl is a prototypical frustrated Kondo lattice with partial long-range
order (LRO) at K. Previous bulk experiments under
hydrostatic pressure found signatures for a quantum critical regime that
extends from GPa, where LRO disappears, up to GPa. We employed extensive muon spin relaxation and rotation (SR)
experiments under pressure. The continuous and complete suppression of LRO at
is confirmed. Above and beyond ,
an additional crossover scale characterizes the change from pure to
stretched exponential relaxation in zero field. Remarkably agrees
with previously determined signatures of entropy accumulation above LRO. This
coincidence microscopically evidences fluctuating frustrated spins at 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 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
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
© 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
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