Nonlinear resistor based on a polymer-ceramic composition

The resistivity of composite nonlinear resistors (varistors) consisting of zinc oxide ceramic and high-density polyethylene, as well as IR spectra and X-ray diffraction patterns taken of the samples, are studied. The component composition of the resistor is shown to influence its resistivity and IR and X-ray spectra.     

Complexes of Cu(II), Ni(II), Co(II), and Ag(I) Metals with 1,4-Bis(3-Phenyl Triazenil) Benzene

Moscow University Chemistry Bulletin - New complexes of Cu(II), Ni(II), Co(II) and Ag(I) with 1,4-bis(3-phenyl triazenyl) benzene are obtained. Using the methods of IR, EPR, electron spectroscopy,...     

Observation of Brillouin scattering in mixed InxGa1−xP crystals

Brillouin scattering is observed in the In_xGa_1?xP solid solution with 0.38 ? × ? 0. The composition dependences of the longitudinal and transverse acoustic phonons propagating along the [111] direction are investigated and compared with the expressions derived by Lakshmi et al. from the random element isodisplacement theory. Pronounced broadening of the Brillouin peaks is observed with the increasing amount of In in GaP.     

On stability of index of Fredholm complexes on the C* -algebra

This article deals with the index of Fredholm complexes of Λ-operators of the Hilbert Λ-modulus on C*-algebra. For this class of operators necessary and sufficient conditions in order to be a Fredholm, are obtained. Based on these results, a notion of Fredholm complex and its index is introduced. For this index, a stability theorem related to various perturbations is proved. In the second part of the article, a completation of a semigroup Fredholm complexes is analysed. It is proved that the group K _G (X, Λ) is the completation of G ? Λ-fibration of the above group on the compact space X.     

Asymptotic formulations of the eigenvalues and eigenfunctions for a boundary value problem

In this work, a discontinuous boundary‐value problem with retarded argument that contains a spectral parameter in the transmission conditions at the point of discontinuity is investigated. We obtained asymptotic formulas for the eigenvalues and eigenfunctions. Copyright © 2012 John Wiley & Sons, Ltd.     

A temperature-compensation mechanism in biochemical oscillation models

Different mechanisms that underlie temperature compensation of the frequency (period) of biochemical self-oscillations are considered. A systemic approach to the elucidation of the molecular nature of temperature compensation of the frequency of biochemical self-oscillations has been characterized as better substantiated. The phenomenon of temperature compensation is not unique for circadian oscillations (“biochemical clocks”) but is rather an inherent property of all multidimensional chemical oscillators. Stages with negative coefficients of control over frequency were shown to be the components of the structure of “presetting generators” of biochemical self-oscillations, and the balancing role of these stages can be considered more important as believed earlier. The calculation of control coefficients showed that the elementary stages make unequal contributions to the mechanism that underlies temperature compensation; therefore, different mutations have dissimilar effects on the temperature compensation of the period of circadian oscillations in the respective mutants.     

On identity for eigenvalues of second order differential operator equation

In this study we investigate the spectrum and regularized trace of the second order differential operator equation with periodic boundary conditions.     

Mechanical Properties of Materials Based on Graphene C62H20 and Polyethylene (–CH2–CH2–)n

Technical Physics - The mechanical properties of materials based on graphene C62H20 and polyethylene (–CH2–CH2–)n have been studied using the semiempirical PM3 method, and visual...     

Application of dual-frequency liquid crystal for tunable selective filtration of infrared radiation

The novel dual-frequency liquid crystal (DFLC) consisting of 4-n-pentyl-4′-cyanobiphenyl (5CB), 4-hexyloxyphenyl ester 4′-hexyloxy-3-nitrobenzoic acid (C2), and 4-n-pentanoyloxy-benzoic acid-4′-hexyloxyphenyl ester (H22) was developed and its basic dielectric characteristics were determined. Transmission spectra of the Al₂O₃ particles-DFLC system in both the ordinary electrooptical cell and the twist-structure were studied. It was shown that for certain changes in the frequency of the applied electric field, a transmission region maximum of the Al₂O₃ particles-DFLC ordinary cell switches from one wavenumber to the other. While the twist-structure of the system at low frequencies passes the light at the same wavenumbers but it becomes practically opaque at high frequencies. The experimental results are explained by the optical homogeneity of the system in a narrow wavelength interval when the refractive indices of the particle material and the matrix are close, and also by reorientation of the liquid crystal molecules as the frequency of the applied voltage changes.     

Simulation of the Electronic Structure of Graphene–Polyvinylidene Fluoride Composite Material

Physics of the Solid State - Theoretical models of shockproof composite materials based on two-layer graphenes and multilayer polyvinylidene fluoride C124H40 + n(H–(C2H2F2)5–H) (n =...