Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 2 )

2019 ( 223 )

2018 ( 314 )

2017 ( 281 )

Custom range...

Search Results: 1 - 10 of 169450 matches for " Sh. E. Kekutia "
All listed articles are free for downloading (OA Articles)
Page 1 /169450
Display every page Item
Acoustical Properties of Superfluid Helium in Confined Geometry
Sh. E. Kekutia,N. D. Chkhaidze
Physics , 2006,
Abstract: The problem studied in this paper is to obtain the equations describing sound propagation in a consolidated porous medium filled with superfluid, determine the elastic coefficients, appearing in the equations, in terms of physically measurable quantities, and calculate the propagation velocities of transverse and longitudinal waves at high and low oscillating frequencies. In general, the obtained equations describe all volume modes that can propagate in a porous medium saturated with superfluid for any values of the porosity and frequencies. The derived equations are applied to the most important particular case when the normal component of superfluid helium is locked inside a highly porous media (aerogel, Im-helium sample) by viscous forces. For this case the velocities of two longitudinal sound modes and transverse mode are calculated from the derived equations. There are established the coupling between temperature and pressure oscillations in these fast and slow modes.
Theory of Sound Propagation in Superfluid Solutions Filled Porous Media
Sh. E. Kekutia,N. D. Chkhaidze
Physics , 2005, DOI: 10.1088/1742-5468/2005/12/P12008
Abstract: A theory of the propagation of acoustic waves in a porous medium filled with superfluid solution is developed. The elastic coefficients in the system of equations are expressed in terms of physically measurable quantities. The equations obtained describe all volume modes that can propagate in a porous medium saturated with superfluid solution. Finally, derived equations are applied to the most important particular case when the normal fluid component is locked inside a highly porous media (aerogel) by viscous forces and the velocities of two longitudinal sound modes are calculated.
Diffusion wave modes and oscillating motions in superfluid $He^3-A$
Sh. E. Kekutia,N. D. Chkhaidze,D. G. Sanikidze
Physics , 2007,
Abstract: Diffusion vibrational modes are studied in superfluid $He^3-A$ in zero magnetic fields for different angles between the orbital axis and the wave vector. The dispersion relation for these modes is found to depend on the wave polarization. It is shown that in addition to the normal component velocity, the superfluid component velocity also oscillates in the diffusion modes of $He^3-A$. The frictional forces due to viscous waves in $He^3-A$, exerted in the plane surface which is in contact with a superfluid liquid layer of finite thickness and performs a simple harmonic oscillatory motion, are calculated. We also consider, volume of $He^3-A$ restricted by two parallel infinite surfaces, when the lower surface accomplishes simple harmonic oscillation and we calculate the frictional forces exerted on surfaces. It is found that the frictional force has not only parallel, but also a perpendicular component relative to the direction of oscillations.
Theory of sound propagation in superfluid-filled porous media
T. Buishvili,Sh. Kekutia,O. Tkeshelashvili,L. Tkeshelashvili
Physics , 2001, DOI: 10.1016/S0375-9601(02)00897-6
Abstract: The theory of sound propagation in macroscopically isotropic and homogeneous porous media saturated with superfluid ^4He(so-called He II) has been developed neglecting all damping processes. The case when the normal fluid component is locked inside a porous medium by viscous forces is investigated in detail. It is shown that in this case one shear wave and two longitudinal, fast and slow, waves exist. Fast wave as well as slow wave is accompanied with temperature oscillations. The velocities of these waves are obtained.
Global Analysis of Solutions of a New Class of Rational Difference Equation  [PDF]
O. Moaaz, E. M. Elabbasy, Sh. Alsaeed
American Journal of Computational Mathematics (AJCM) , 2017, DOI: 10.4236/ajcm.2017.74036
Abstract: The study suggests asymptotic behavior of the solution to a new class of difference equations: \"\". where a, bi, α and β are positive real numbers for i = 0, 1, · · · , k , and the initial conditions ψ-j, ψ-j+1, · · ·, ψ0 are randomly positive real numbers where j = 2k + 1. Accordingly, we consider the stability, boundedness and periodicity of the solutions of this recursive sequence. Indeed, we give some interesting counter examples in order to verify our strong results.
Prosthetic rehabilitation for a patient with microstomia: a case report
Moslehifard E,Safaeian Sh
Journal of Dental Medicine , 2011,
Abstract: "nFabrication of dental prosthesis for patients with microstomia has long been a problem for dentists. Microstomia is defined as an abnormally small oral orifice. Prosthetic rehabilitation of microstomia patients presents difficulties at all stages, from the preliminary impressions to fabrication of prosthesis. This study described a method for making impressions for patients with limited opening of the oral cavity which the use of a full-size impression tray was not possible.
The study of hospital bavage solution and calorie and protein in take. For patients needs from the special care unit at Imam Khomeini hospital, Sari, Iran during 2005
E. Salehifar,Sh. Ala
Journal of Mazandaran University of Medical Sciences , 2008,
Abstract: Background and Purpose: Malnutrition is a major problem within intensive care units (ICU) affecting the outcome of patients. In Imam Khomeini Hospital, patients were fed with gavage solutions prepared in the kitchen of hospitals, however, its' nutritional value has not been studied at present time. The aim of this study was to analyze the gavage solution and to compare the calculated nutritional demand with the provided values.Materials and Methods: The amount of carbohydrate, lipid and protein of gavage solution has been determined with Leen ion, Gerber and Kejeldal methods, respectively. In this study, 30 patients with at least 5 days in the ICU were included. Daily metabolic needs were calculated with Harris-Benedict equation and then, calculated calorie and protein values were compared with the provided values.Results: The carbohydrate, lipid, protein and energy contents of gavage solutions were 0.035 ±0.002 g/ml, 0.0225±0.017 g/ml, 0.012 ± 0.002 g/ml, and 0.39 ± 0.164 Kcal/ml. The calorie and protein provided by the hospital solution, in comparison to the standard enteral solutions, were 32.5% and 16% respectively. Total energy expenditure (TEE) at the time of admission to ICU was 2302 ± 633 Kcal/ per day. During week 1, 2, and 3, TEE was 2301±634, 2283 ± 661 and 2228 ± 790 respectively. Maximum provided energy was 600 ± 632 Kcal/ per day. Maximum protein was provided in week 3 and equal to 22.9% of patient’s needs.Conclusion: The gavage solution provided by hospitals can not meet the calorie and protein needs of patients. It is necessary to prepare solutions with enough contents of carbohydrate, lipid and protein or to provide them with standard enteral nutritional solutions.Key words: Gavage, Intensive care unit, Malnutrition, Calorie, ProteinJ Mazand Univ Med Sci 2008; 18(64): 81-85 (Persian)
On canonical variables in integrable models of magnets
E. Sh. Gutshabash
Physics , 2007,
Abstract: Three integrable models - the deformed Heisenberg, Landau - Lifschits and Ishimori magnets are written in terms of the stereographic projection. The Hamiltonians of these models are obtained and certain questions related to the existence of exact solutions are studied. In particular, the stability of solitions is studied for the Heisenberg marnet, simplest stationary solutions are obtained for the Landau - Lifschits magnet, and Hamiltonians and topological charges are calculated for several known solutions of the Ishimori model
Darboux Transformation for the Non-stationary Shr?dinger Equation
E. Sh. Gutshabash
Physics , 2005,
Abstract: The Lax representation for the nonstationary Schr\"odinger equation with rather arbitrary potential is proposed. Some examples of the construction of exact solutions are given by means of Darboux Transformation method.
Some notes on Ishimori's magnet model
E. Sh. Gutshabash
Physics , 2003,
Abstract: Gauge transformation properties for an associated linear system of model Ishimori's magnet model have been discussed. Explicit formulas for the gauge transformation matrix have been obtained. Darboux Transformation has been suggested and appropriate dressing relations have been found.
Page 1 /169450
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.