Structural Polarization in the Conductor–Insulator System

Technical Physics - The electrophysical properties of an insulator–conductor composite are studied. It is shown that the introduction of conductive phase in the insulator allows significant...     

Wavelet Correlation in the One-Dimensional Projection α-Model

One-dimensional projection of two-dimensional self-affine phase space for two typical self-affine fractals is studied,and one-dimensional projection α model is obtained.About this model,starting from characterstic function,we study its correlation densities and the wavelet correption moment.The wavelet basis functions of split number Λ=2,3,4 are found out.It turns out that the various wavelet-coefficents decouple when the second order wavelet correlation moments are considered.This is a general conclusion and model independent.     

Velocity Distribution of the Powder Particles in Laser Cladding

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｏｖｅｒｔｈｅｌａｓｔｄｅｃａｄｅｓ,ｔｈｅｈｉｇｈｐｏｗｅｒｌａｓｅｒｂｅａｍｓａｒｅｎｏｗｗｉｄｅｌｙｕｓｅｄｉｎｍａｔｅｒｉａｌｐｒｏｃｅｓｓｉｎｇ .Ｔｈｅｓｅａｐｐｌｉｃａｔｉｏｎｓｈａｖｅｍａｄｅｇｒｅａｔｐｒｏｇｒｅｓｓｗｉｔｈｓｉｇｎｉｆｉｃａｎｔｓｕｃｃｅｓｓ[1,2 ] .Ｔｈｅｌａｓｅｒｃｌａｄｄｉｎｇ ,ｗｈｉｃｈｕｓｅｓａｈｉｇｈｐｏｗｅｒｌａｓｅｒａｓｔｈｅｈｅａｔｉｎｇｓｏｕｒｃｅｔｏｆｏｒｍａｃｌａｄｏｎｔｏｔｈｅｓｕｒｆａｃｅｏｆｓｕｂｓｔｒａ…     

Structural asymmetry in liquid Fe–Si alloys

The thermodynamic properties and microscopic structure of liquid Fe–Si alloys at 1873 K were studied by using the regular associated solution model. The model was utilized to determine the complex concentration in a regular associated solution of Fe, Si and Fe₂Si. The complex concentration was then used to calculate the integral excess free energy of mixing, activity, concentration fluctuations in the long-wavelength limit, S_CC (0), and the Warren–Cowley short-range parameter α ₁. The analysis suggests that heterocoordination leading to the formation of complex Fe₂Si is likely to exist in the liquid and is of a strongly interacting nature. The theoretical analysis reveals that the alloy is more ordered towards the Fe-rich region. The observed asymmetry in the properties of mixing of Fe–Si alloys in the molten state is successfully explained on the basis of the regular associated solution model.     

Structural and magnetic investigations in the vicinity of first-order transformations in Ni–Mn–Ga–Co ferromagnetic shape memory alloys

Among the series of alloys derived from Ni₅₀Mn₂₉Ga₂₁ on selective substitution of Co for Ni and Mn, two alloys Ni_49.8Mn_27.2Ga_21.2Co_1.8 and Ni_46.9Mn_28.8Ga₂₁Co_3.3 referred to as CoMn-1.8 and CoNi-3.3, respectively, are found to exhibit an additional first-order transformation below their martensitic transformation temperatures. Systematic studies on temperature and field dependence of magnetic properties of these alloys are carried out, through the transformations, to understand their origin. An examination of these results in conjunction with those from structural investigations reveals that the transformation in the CoMn-1.8 alloy is an intermartensitic transformation and has a structural origin, while that in the CoNi-3.3 alloy is not of the structural origin and is attributed to local spin inversion of Co moments, which is of the magnetic origin.     

Spectral‐Polarization Contrasts in the Problems of Remote Sensing

The results of the investigation of the angular and spectralpolarization characteristics of 4501080nm radiation reflected from the surfaces of natural (leaves of trees, bark) and artificial (colored smooth surface, fabric) objects are discussed. Based on a study of the contrasts between these characteristics, we have determined the most informative spectralpolarization characteristics and the spectral and angular intervals the use of which in remote optical observations of objects would allow their most effective discrimination.     

Correlation femtoscopy of Λ hyperons in the SELEX experiment

Study of the correlations of two identical particles with a small relative difference in their 4-momenta can provide information on the space-time behavior of a source and the shape of the potential between the particles. Our study of correlations is based on the SELEX experimental data. From a set of events involving Λ pairs, we selected the approximately ∼2600 such events with the best kinematical parameters, on the basis of which the preliminary results from our analysis of ΛΛ system correlations are presented.     

Deterministic Remote Preparation via the χ State in Noisy Environment

International Journal of Theoretical Physics - We have proposed two deterministic remote state preparation schemes via the χ state as the entangled channel in ideal environment. In this paper,...     

Magneto-optic Faraday effect in maghemite nanoparticles/silica matrix nanocomposites prepared by the Sol–Gel method

Bulk monolithic samples of γ-Fe₂O₃/SiO₂ composites with different iron oxide/silica ratios have been prepared by the sol–gel technique. Iron oxide nanoparticles are obtained in-situ during heat treatment of samples and silica matrix consolidation. Preparation method was previously optimized to minimize the percentage of antiferromagnetic α-Fe₂O₃ and parallelepipeds of roughly 2×5×12 mm³, with good mechanical stability, are obtained. RT magnetization curves show a non-hysteretic behavior. Thus, magnetization measurements have been well fitted to an expression that combines the Langevin equation with an additional linear term, indicating that some of the nanoparticles are still superparamagnetic as confirmed by X-ray diffraction and electron microscopy measurements. Zero field cooled /field cooled experiments show curves with slightly different shapes, depending on the size and shape distribution of nanoparticles for a given composition. Magneto-optical Faraday effect measurements show that the Faraday rotation is proportional to magnetization of the samples, as expected. As a demonstration of their sensing possibilities, the relative intensity of polarized light, measured at 5° from the extinction angle, was plotted versus applied magnetic field.     

Direct Measurement of the Correlation Function of Optical–Terahertz Biphotons

JETP Letters - The second-order correlation function which characterizes the quantum correlation between the optical and terahertz photons generated under spontaneous parametric down-conversion has...     

Ab Initio Study of the Structural Properties of the Co–Ni–Sn Heusler Alloys

Physics of the Solid State - The ab initio investigations of the structural and magnetic properties of the Co2Ni1 + xSn1 – x (x = 0,...     

Gel stabilization in chelate sol–gel preparation of Bi-2223 superconductors

A chelating sol–gel method was used for the preparation of the superconducting Bi-2223 phase. We compared pH range of both solution and gel stability in samples with EDTA, TEA and their equimolar mixture addition. A pH range of stability (for precipitation) was extended in EDTA solutions with addition of TEA. IR spectroscopy was used to identify the type of bonding between EDTA and TEA in a stabilized solution. IR bands belonging to polyester bonding were found in the IR spectra of gels prepared at 130 °C. We describe the influence of both gel decomposition and calcinations regime on the evolution of Bi-2223 phase. The optimized temperature treatment was used for the comparison of superconducting transport and of magnetic properties of the prepared samples. Moreover, an extra 800 °C calcination step was tested to enhance the decomposition of unfavorably formed carbonates.     

Correlation between Quantum Entanglement and Quantum Coherence in the Case of XY Spin Chains with the Dzyaloshinskii–Moriya Interaction

Journal of Experimental and Theoretical Physics - Recently, there has been an increased interest in studying quantum entanglement and quantum coherence. Since both of these properties are...     

Vibrational Spectra of Ion–Molecular Carbonate Crystals in the Pretransition Region near Structural Phase Transitions

Optics and Spectroscopy - Molecular relaxation processes in lithium (Li2CO3), sodium (Na2CO3), and potassium (K2CO3) carbonates are studied by Raman spectroscopy. It is found that the first-order...