Generalized contour models

The paper is devoted to a survey and systematic exposition of the technique of obtaining cluster expansions for lattice Gibbs fields in the low-temperature region in the case of a finite or countable number of basic states.     

Thermal fracture of macrocrack with closure as influenced by microcracks

The fracture stability of macrocracks under uniform heat flux is analyzed to include the effect of a system of microcracks. The interaction of cracks leads to full or partial closure of crack surfaces. The boundary problem is stated and a solution is obtained. The domains where microcracks are closed and/or affect partial closing of the macrocrack are found. Evaluated is the macrocrack tip stress intensity factor accounting for closure.     

Elastic properties of FeSi

Measurements of the sound velocities in a single crystal of FeSi were performed in the temperature range 4–300 K. Elastic constants C ₁₁ and C ₄₄ deviate from a quasiharmonic behavior at high temperature; on the other hand, elastic constants C ₁₂ increases anomalously in the entire temperature range, indicating a change in the electron structure of this material.     

Lost heat capacity and entropy in the helical magnet MnSi

The heat capacity of MnSi at B = 0 and B = 4 T was measured in the temperature range 2.5-100 K. To analyze the data, calculations of the phonon spectrum and phonon density of states in MnSi were performed. The calculated phonon frequencies were confirmed by means of inelastic neutron scattering. The analysis of the data suggests the existence of negative contributions to the heat capacity and entropy of MnSi at T > T(c) that may imply a specific ordering in the spin subsystem in the paramagnetic phase of MnSi.     

Modelling and simulation of bicable ropeways under cross-wind influence

Improvements of safety standards of ropeways are crucial in order to ensure a high level of operational reliability and safety. In this context, the question of cross-wind stability of ropeways is of particular concern. The real cross-inclination of the gondola and its correlation to wind speed and direction on an operating ropeway are of great interest for ropeway manufacturers and responsible authorities as well as for ropeway operators. As presented in this paper, a mathematical model for simulation was developed in order to gain a better understanding of the cross-wind behaviour of bicable ropeways. This model was established for a numerical dynamic simulation of the movement of gondolas with stiff connections, ‘hanger-cabins’, due to arbitrary cross-wind loads acting at a section of the studied span of the ropeway. All equations were solved using the program MATLAB® and the toolbox SIMULINK®. In addition, the results of a simulation of a real ropeway are presented.     

The possibility of using cryofiber interferometer as detector of gravitational waves

The history of the question on the possibility of detecting gravitational waves, whose existence is predicted by the General Relativity Theory, is briefly presented. The schemes of cryofiber interferometer, which we propose to use as detector of gravitational waves with amplitude |δg _ij | = 10^?20, are described. We also consider other versions of the use of cryofiber interferometer in both applied and fundamental context, including laboratory experiments in which according to the estimates dark energy density variations can be detected. We describe briefly the optical scheme of a compact interferometric detector of vibrations of a mirror fixed at the end of a massive gravitational antenna; the compactness admits construction of a cryogenic version with cooling of all the elements of such a recording system.     

Hydrogen associative desorption from Ru(1010)

The associative desorption of hydrogen from the Ru(10 0) surface has been studied on the atomic level by means of density-functional calculations with various exchange-correlation functionals and kinetic Monte Carlo simulations. The simulations reproduce forming structures of the layers and main features of TPD spectra for a wide range of hydrogen coverages. In particular, it has been shown that the decrease of binding energies with coverage due to lateral repulsion is correlated with the appearance of low-temperature peaks in the spectra.     

Fabrication of LIGA masks for microfluidic analytical systems

Preliminary results of fabrication and testing of LIGA mask samples for deep x-ray lithography in the spectral range of 3.5–13.5 keV are presented. The mask fabrication method is based on direct mask patterning with minimum element sizes of ≥ 10 μm by a synchrotron radiation x-ray microbeam. Such a method does not require an intermediate mask, which significantly simplifies fabrication and reduces the laboriousness and cost of LIGA masks.     

Novel 5-N,N-disubstituted-5-amino-3-(2-oxopropyl)-1,2,4-thiadiazoles: synthesis and study of neuroprotective and antiproliferative properties

Russian Chemical Bulletin - A series of eight novel 5-N,N-disubstituted-5-amino-3-(2-oxopropyl)-1,2,4-thiadiazoles with diverse lipophilic groups was obtained by reaction of...     

Halocyclization of 3-Allyl-5-ethyl-6-methyl-2-thiouracil

Russian Journal of Organic Chemistry - The reaction of N-allylthiourea with ethyl 2-ethyl-3-oxobutanoate gave 3-allyl-5-ethyl-6-methyl-2- thiouracil which reacted with bromine and iodine to afford...