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1.
The properties of the Earth’s solid crust have been studied on the assumption that this crust has a block structure. According to the rotation model, the motion of such a medium (geomedium) follows the angular momentum conservation law and can be described in the scope of the classical elasticity theory with a symmetric stress tensor. A geomedium motion is characterized by two types of rotation waves with shortand long-range actions. The first type includes slow solitons with velocities of 0 ≤ Vsol ≤ c0, max = 1–10 cm s–1; the second type, fast excitons with V0VexVSVP. The exciton minimal velocity (V0 = 0) depends on the energy of the collective excitation of all seismically active belt blocks proportional to the Earth’s pole vibration frequency (the Chandler vibration frequency). The exciton maximal velocity depends on the velocities of S (VS ≈ 4 km s–1) and/or P (VP ≈ 8 km s–1) seismic (acoustic) waves. According to the rotation model, a geomedium is characterized by the property physically close to the corpuscular–wave interaction between blocks that compose this medium. The possible collective wave motion of geomedium blocks can be responsible for the geomedium rheidity property, i.e., a superplastic volume flow. A superplastic motion of a quantum fluid can be the physical analog of the geomedium rheid motion.  相似文献   

2.
The values of density, viscosity and speed of sound for the binary liquid mixture of Benzaldehyde with Benzene were measured over the entire range of composition at 303.15, 308.15, and 313.15 K. These values are used to calculate the excess molar volume (V E), deviation in viscosity (Δη), deviation in speed of sound (ΔU), deviation in isentropic compressibility (Δβ s ), excess internal pressure (Δπ), excess intermolecular free length (ΔL f ), excess free volume (V E f ) and excess acoustic impedance (ΔZ). McAllister’s three-body interaction model is used for correlating Kinematic Viscosity of binary mixtures. The excess values were correlated using the Redlich–Kister polynomial equation to obtain their coefficients and standard deviations. The thermophysical properties (density, viscosity, and speed of sound) under the study were fit to the Jouyban–Acree model.  相似文献   

3.
The electron spin resonance has been measured for the first time both in the paramagnetic phase of the metallic GdB6 antiferromagnet (TN = 15.5K) and in the antiferromagnetic state (T < TN). In the paramagnetic phase below T* ~ 70 K, the material is found to exhibit a pronounced increase in the resonance linewidth and a shift in the g-factor, which is proportional to the linewidth Δg(T) ~ ΔH(T). Such behavior is not characteristic of antiferromagnetic metals and seems to be due to the effects related to displacements of Gd3+ ions from the centrosymmetric positions in the boron cage. The transition to the antiferromagnetic phase is accompanied by an abrupt change in the position of resonance (from μ0H0 ≈ 1.9 T to μ0H0 ≈ 3.9 T at ν = 60 GHz), after which a smooth evolution of the spectrum occurs, resulting eventually in the formation of the spectrum consisting of four resonance lines. The magnetic field dependence of the frequency of the resonant modes ω0(H0) obtained in the range of 28–69 GHz is well interpreted within the model of ESR in an antiferromagnet with the easy anisotropy axis ω/γ = (H 0 2 +2HAHE)1/2, where HE is the exchange field and HA is the anisotropy field. This provides an estimate for the anisotropy field, HA ≈ 800 Oe. This value can result from the dipole?dipole interaction related to the mutual displacement of Gd3+ ions, which occurs at the antiferromagnetic transition.  相似文献   

4.
A diamond anvil cell is used to investigate the effect of high pressure (up to 37.5 GPa) on the optical absorption spectra of a single crystal of nickel oxide (NiO). In addition, strain-gage measurements are used to experimentally investigate the V(P) equation of state at a hydrostatic pressure of up to 8.5 GPa in a high-pressure chamber of the “toroid” type. Measurements are performed at room temperature. Absorption bands are observed, which correspond to optical d-d transitions of Ni2+ ion in the crystal field of ligands 3A2g3T2g, 3A2g → {au1}E1g, 3A2g3T1g(F), and 3A2g1T2g. The values of energy of these transitions increase linearly with pressure, and their pressure coefficients are 7.3 ± 0.2, 2.87 ± 0.9, 9.7 ± 0.5, and 8.9 ± 0.3 meV/GPa, respectively. The pressure derivative of the crystal field parameter 10Dq corresponding to the 3A2g3T2g transition gives the pressure dependence of the magnitude of exchange integral J in the Anderson hybridization model. It is found that, in the pressure range from zero to 37.5 GPa, the behavior of the exchange integral J is largely defined by the hybridization parameter b = (10Dq/3). At the same time, the Coulomb interaction parameter Ueff is independent of pressure and, therefore, has no effect on the variation of J. The Coulomb interaction Ueff ≈ 7.47 ± 0.005 eV is determined. The experimental data on the equation of state are used to derive the \(J \propto V^\varepsilon \) correlation, where ε = ?2.99 ± 0.15, which is in good agreement with the predictions of Bloch’s theory (ε = ?10/3).  相似文献   

5.
The special features of the dielectric properties and conduction of ferroelectric crystals of Pb5(Ge1?xSix)3O11 (0 ≤ x ≤ 0.67) solid solutions were studied. Permittivity anomalies close to the temperatures T1 ≈ 260 K and T2 ≈ 130 K, the appearance of relaxator behavior at x > 0.35, and critical behavior of the concentration dependences of dielectric and pyroelectric characteristics at x1 = 0.35 and x2 = 0.60 were observed and studied. These phenomena were found to be related to the dynamics of charge localization on defects with activation energies of Ua1 ≈ 0.6 eV and Ua2 ≈ 0.23 eV. Relaxator behavior appears when the Curie point lies in the temperature region of thermal charge localization. The concentration dependence features at x1 and x2 are explained by the coincidence of the Curie point and the centers of the temperature regions of charge localization on the Ua1 and Ua2 defect levels, respectively.  相似文献   

6.
The isotopically invariant Dunham parameters U mj , Δ mj H and Δ mj Cl were determined by simultaneously fitting the line centers of vibration-rotation transitions of six isotopic HCl forms in the ground electronic state. Fitting included relations between U mj values. The parameters of the isotopically invariant potential of HCl were determined using independent U m0 and U m1 values. The contributions to the vibrational terms of H35Cl caused by violation of the Born-Oppenheimer approximation were calculated.  相似文献   

7.
The selective reflection of laser radiation from the interface between a dielectric window and the atomic vapors confined in a nanocell of thickness L ≈ 350 nm is used to develop effective Doppler-broadening- free spectroscopy of potassium atoms. A small atomic line width and a relation between the signal intensity and the transition probability allowed us to resolve four lines of atomic transitions responsible for the D1 lines of the 39K and 41K isotopes. Two groups containing four atomic transitions form in an applied magnetic field upon pumping by radiation with circular polarization σ+ or σ. Different intensities (probabilities) of transitions for the σ+ and σ excitations are detected in magnetic field B0A hfs B ≈ 165 G (A hfs is the magnetic dipole constant for the ground state and μB is the Bohr magneton). A substantially different situation is observed at B ? B0, since high symmetry appears for the two groups formed by radiation with circular polarization σ+ or σ. Each group is the mirror image of the other group with respect to the frequency of the 42S1/2–42P1/2 transition, which additionally proves the occurrence of the complete Paschen–Back regime of the hyperfine structure at B ≈ 2.5 kG. A developed theoretical model well reproduces the experimental results. Possible practical applications are described. The results obtained can also be applied to the D1 lines of 87Rb and 23Na.  相似文献   

8.
Relations between the form factors of the weak leptonic baryon interaction are obtained from invariance under the groupSU 3?SU 3?U 1. The weak interaction operatorV μ ?A μ is assumed to behave like the corresponding components of representations35 ofSU 6 with different parities. One gets the result that the well-known predictions of the staticSU 6 theory, viz., pureF-coupling for the vector- and 3D+2F-coupling for the axial-vector part, are only valid in the limit of vanishing momentum transfer. In the same limit the resultC A /C V =?\(\tfrac{5}{3}\) is obtained if one further assumes thatV 0 and\(\vec A\) belong to thesame representation35 ofSU 6.  相似文献   

9.
The influence of the bias voltage polarity Us on microstructure, crystallographic texture and magnetic properties has been investigated for Ni films with a thickness of ≈15–420 nm, which are obtained via magnetron sputtering at a working gas pressure P corresponding to the collision-deficient flight mode of atoms of the sputtered target between the target and the substrate. The Ni(111)-textured films have been shown to form at Us ≈–100 V, whose microstructure and magnetic parameters are almost unchanged with a thickness. In contrast, the Ni(200) films are formed at Us ≈ +100 V, whose magnetic properties and micro-structure depend significantly on the thickness d that manifests in a critical thickness d* ≈ 150 nm, when the structure of the film becomes inhomogeneous in the thickness, the remagnetization loops are changed from rectangular to supercritical with the formation of the band domain structure.  相似文献   

10.
A physical picture of the origin of lepton mass is presented on the basis of the byuon theory (BT). The BT is the theory of the life of special unobservable discrete objects: byuons, from which the world surrounding us are formed (physical space; fundamental constants h, e, c; the mass of elementary particles; the four fundamental interactions; the predicted new force in nature, and so on). A key difference between this theory and current models of the classical and quantum field theories is that the potentials of physical fields acquire precise fixable, measurable values. The definition of byuon contains a new fundamental vector constant: the cosmological vector potential (Ag ≈ 1.95 × 1011 G cm). The BT contains only three constants: \(\tilde x_0 \) ≈ 2.78 × 10–33 cm, τ0 ≈ 0.927 × 10–43 s, and a modulus of Ag that allows us to obtain the masses of all known leptons and predict the mass of the next lepton (80.4 GeV).  相似文献   

11.
In this paper we present an expression relating the cohesive energy (E coh in kcal/mol) of AIIIBV and AIIBVI semiconductors with the product of ionic charges (Z 1 Z 2) and nearest-neighbour distance d (Å). The cohesive energy values of these solids exhibit a linear relationship when plotted on a log-log scale against the nearest-neighbour distance d (Å), but fall on different straight lines according to the ionic charge product of the solids. A good agreement has been found between the experimental and calculated values of the cohesive energy of AIIIBV and AIIBVI semiconductors.  相似文献   

12.
Full-electron calculations of the electronic structure of the TiSi2 compound in the structural modification C49 are performed using the augmented-plane-wave method. The total energy, the electronic band structure, and the density of states are calculated for an extended translational unit cell Ti4Si8, which is formed during the growth of a silicon nanowire on a p-Si substrate. Calculations are also carried out for two orthorhombic unit cells of the nonstoichiometric compositions Ti3Si9 and Ti5Si7. The energies of the interatomic bonds are determined to be E Si-Si = 1.8 eV, E Ti-Ti = 2.29 eV, and E Ti-Si = 4.47 eV. The dependence of the total energy of the unit cell E tot(V) on the unit cell volume V is obtained by optimizing the unit cell volume. The bulk modulus B 0 = 132 GPa is determined from the Murnaghan equation of state for solids and the dependence E tot (V). This value of the bulk modulus is used to estimate the activation energy for interstitial diffusion of silicon atoms Q i(Si) ≈ 0.8 eV.  相似文献   

13.
14.
Theβ-α. angular correlationW(Θ)=1+a cosΘ+cos2 Θ of the decay of Li8 was measured for average electron energies ofE β ≈5 MeV, 11 MeV and 12 MeV. The experiment yields an anisotropyA=(0·0036±0·0011)·E β (MeV)?1. This result is in good agreement with the results of the other groups. The measurements were performed in a counting chamber separated from the activation room simultaneously for two sealer positionsΘ=90° and 180°. The result is discussed in terms of the CVC-theory, taking into account the second forbidden Fermi-matrixelements (‖M1‖) and (‖E2‖).  相似文献   

15.
The penetration of a magnetic flux into a type-II high-T c superconductor occupying the half-space x > 0 is considered. At the superconductor surface, the magnetic field amplitude increases in accordance with the law b(0, t) = b 0(1 + t)m (in dimensionless coordinates), where m > 0. The velocity of penetration of vortices is determined in the regime of thermally activated magnetic flux flow: v = v 0exp?ub;?(U 0/T )(1-b?b/?x)?ub;, where U 0 is the effective pinning energy and T is the thermal energy of excited vortex filaments (or their bundles). magnetic flux “Giant” creep (for which U 0/T? 1) is considered. The model Navier-Stokes equation is derived with nonlinear “viscosity” vU 0/T and convection velocity v f ∝ (1 ? U 0/T). It is shown that motion of vortices is of the diffusion type for j → 0 (j is the current density). For finite current densities 0 < j < j c, magnetic flux convection takes place, leading to an increase in the amplitude and depth of penetration of the magnetic field into the superconductor. It is shown that the solution to the model equation is finite at each instant (i.e., the magnetic flux penetrates to a finite depth). The penetration depth x eff A (t) ∝ (1 + t)(1 + m/2)/2 of the magnetic field in the superconductor and the velocity of the wavefront, which increases linearly in exponent m, exponentially in temperature T, and decreases upon an increase in the effective pinning barrier, are determined. A distinguishing feature of the solutions is their self-similarity; i.e., dissipative magnetic structures emerging in the case of giant creep are invariant to transformations b(x, t) = βm b(t/β, x(1 + m/2)/2), where β > 0.  相似文献   

16.
This paper presents the complete set of polarization angular coefficients A 0?7 describing lepton angular distributions in Z boson decay, which were measured at the ATLAS experiment in proton–proton collisions with the energy √s = 8 TeV. Theoretical values for the difference A 0 ? A 2 calculated in the fixed-order QCD perturbation theory O(α s 2 ), demonstrate significant deviation from the measured data, which indicates the necessity of taking into account higher order corrections. The evidence of nonzero coefficients A 5,6,7 was obtained for the first time, in accordance with theoretical calculations in O(α s 2 ) approximation. Measurement of the polarization angular coefficients A i is important for subsequent precision measurement of parameters of the electroweak model at the LHC, such as the sine of Weinberg electroweak mixing angle sin2 θ W and the W boson mass.  相似文献   

17.
The anomalous behavior of the isochoric heat capacity of a mixture of methane, pentane and heptane is studied experimentally in the vicinity of the liquid-vapor critical point in the cases when (a) the critical temperature T c approaches the tricritical point T TCP and (b) the critical temperature approaches the upper critical end point T U . It is shown that in all cases, the singular part of the heat capacity of the mixture has the form Csing=A¦τ¦, where τ=(T ? T c )/T c and α≈0.11. When T c T U , amplitude A of the heat capacity anomaly is found to be approximately constant. At the same time, the amplitude of the anomaly tends to zero in the vicinity of the tricritical point: A∝¦τc¦ε, where τc=(T c ? T TCP )/T TCP and ε=1.6?1.7. The inevitable vanishing of this mode of the heat capacity anomaly leads to a negative value of the critical index \(\tilde \alpha\) characterizing the heat capacity anomaly at the tricritical point, while the tricritical point theory and the isomorphism hypothesis predict \(\tilde \alpha = 0.5\).  相似文献   

18.
19.
We study the asymptotic structure of the first K largest eigenvalues λ k,V and the corresponding eigenfunctions ψ(?;λ k,V ) of a finite-volume Anderson model (discrete Schrödinger operator) \(\mathcal{H}_{V}= \kappa \Delta_{V}+\xi(\cdot)\) on the multidimensional lattice torus V increasing to the whole of lattice ? ν , provided the distribution function F(?) of i.i.d. potential ξ(?) satisfies condition ?log(1?F(t))=o(t 3) and some additional regularity conditions as t→∞. For zV, denote by λ 0(z) the principal eigenvalue of the “single-peak” Hamiltonian κΔ V +ξ(z)δ z in l 2(V), and let \(\lambda^{0}_{k,V}\) be the kth largest value of the sample λ 0(?) in V. We first show that the eigenvalues λ k,V are asymptotically close to \(\lambda^{0}_{k,V}\). We then prove extremal type limit theorems (i.e., Poisson statistics) for the normalized eigenvalues (λ k,V ?B V )a V , where the normalizing constants a V >0 and B V are chosen the same as in the corresponding limit theorems for \(\lambda^{0}_{k,V}\). The eigenfunction ψ(?;λ k,V ) is shown to be asymptotically completely localized (as V↑?) at the sites z k,V V defined by \(\lambda^{0}(z_{k,V})=\lambda^{0}_{k,V}\). Proofs are based on the finite-rank (in particular, rank one) perturbation arguments for discrete Schrödinger operator when potential peaks are sparse.  相似文献   

20.
By calculating the optical spectrum band positions and EPR parameters (g factors, g‖, g⊥ and zero-field splitting D) by diagonalizing the complete energy matrix of 3d8 ions in trigonal symmetry, the defect structure of Ni2+ centre in α-LiIO3 crystal is studied. It is found that to reach the good fits of optical and EPR data between calculation and experiment, the Ni2+ ion should shift by Δz ≈ 0.298 Å along C3-axis and the O2? ions between the Ni2+ ion and Li+ vacancy (V Li) should be displaced away from the V Li by Δx ≈ 0.097 Å because of the electrostatic interaction. The results are discussed.  相似文献   

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