Materials physics and mechanics

RAR RUS 1-24 59122315900 0000-0002-1572-2108 Kurukshetra University Kumar Rajneesh

Kurukshetra, India

Kurukshetra University Gupta

India

Uniqueness, reciprocity theorem and variational principle in fractional order theory of thermoelasticity with voids In this work, a new theory of thermoelasticity with voids is discussed by using the methodology of fractional calculus. The governing equations for particle motion in a homogeneous anisotropic fractional order thermoelastic medium with voids are presented. A variational principle, uniqueness theorem and reciprocity theorem are proved. The plane wave propagation in orthotropic thermoelastic material with fractional order derivative and voids is studied. For two-dimensional problem there exist quasi-longitudinal (qP) wave, quasi-transverse (qS) wave, quasi-longitudinal thermal (qT) wave and a quasi-longitudinal volume fractional (qV) wave. From the obtained results the different characteristics of waves like phase velocity, attenuation coefficient, specific loss and penetration depth are computed numerically and presented graphically. anisotropic; orthotropic; thermoelasticity with voids; fractional calculus; uniqueness theorem; variational principle; reciprocity theorem https://mpm.spbstu.ru/article/2013.26.1/ MPM_2012_16_1_P01.pdf

RAR RUS 25-33 Shri Sant Gadge Maharaj College Ravangave

India

Mahatma Basweshwar College Biradar

India

Study of optical parameters of chemical bath deposited Cd1-xZnxS thin films The Chemical Bath Deposition Method (CBD) was employed for deposition of Cd1-xZnxS (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) thin films. The chemically deposited Cd1-xZnxS thin films were characterized by using UV-Visible spectrophotometer. Transmission spectra show the blue shifting of absorption edge as the Zn content increased. The x = 0.8 composition shows maximum 78 % transmittance. The reflection in the blue portion of the incident spectrum was decreased as the Zn content increased. The (αhν)2 versus photon energy (hν) curves shows tuning of band gap with Zn content. The observed band gap was 3.9 eV in the x = 0.8 composition. The effect of composition on refractive index, absorption index and other optical dispersion parameters were also investigated. The calculated values of average excitation energy Eo approximately obey the empirical relation (Eo=1.2 Eg) obtained from single oscillator model. Chemical Bath Deposition band gap optical constants https://mpm.spbstu.ru/article/2013.26.2/ MPM_2012_16_1_P02.pdf

RAR RUS 34-54 59122315900 0000-0002-1572-2108 Kurukshetra University Kumar Rajneesh

Kurukshetra, India

Deenbandhu Chhotu Ram University Garg

Murthal (Sonipat), India

Kurukshetra University Ahuja

India

A study of plane wave and fundamental solution in the theory of an electro-microstretch generalized thermoelastic solid The present article deals with the study of propagation of plane wave and fundamental solution in an electro-microstretch generalized thermoelastic solid. It is found that for two dimensional model, there exist three coupled longitudinal waves, namely longitudinal displacement wave (LD-wave), thermal wave (T-wave), longitudinal microstretch wave (LM-wave) and two coupled transverse displacement and transverse microrotational (CD I, CD II) waves. The phase velocity, attenuation coefficient, specific loss and penetration depth are computed numerically and depicted graphically. In addition, we construct the fundamental solution of the system of differential equations in the theory of an electro-microstretch generalized thermoelastic solid in case of steady oscillations in terms of elementary functions. Some basic properties of the fundamental solution are established. Some special cases are also discussed. steady oscillations; electro-microstretch; phase velocity; attenuation coefficient; fundamental solution https://mpm.spbstu.ru/article/2013.26.3/ MPM_2012_16_1_P03.pdf

RAR RUS 55-65 Razi University of Kermanshah Goudarzi

Iran

Razi University of Kermanshah Niazi

Iran

University of Tehran Besharati

Iran

Hybrid energy harvesting from vibration and temperature gradient by PZT and PMN-0.25PT ceramics Energy harvesting is the act of scavenging small amounts of power from the ambient energy resources. Such ambient energy can come from various green energy sources such as solar, thermal, wind, and kinetic energy. These amounts of energy can power up sensor nodes and therefore reduce the wiring complications or eliminate the need of changing batteries frequently. Two of the most popular methods for harvesting energy consisted of the application of piezoelectric and pyroelectric materials in scavenging energy from vibration and thermal gradients, respectively. This paper presents a hybrid harvesting technique by piezoelectric and pyroelectric effect, simultaneously. The concept of method and theoretical analysis is presented in details for parallel and series SSHI (synchronize switch harvesting on inductor). Numerical results are examined and show better performance compare with piezogenerators for PZT and PMN-0.25PT elements. In this paper it has been proven that hybrid energy harvesting energy by pyroelectric and piezoelectric effect, simultaneously, increases almost 38 % and 53 % more power as it does harvest by just piezoelectric effect. Followed by mentioned analyses the effect of three important parameters - temperature amplitude, vibration amplitude, and frequency- are examined. The more effective harvesting method and material is proposed in the final part of the paper. energy harvesting; piezoelectric; pyroelectric; MEMS; hybrid technique SSHI https://mpm.spbstu.ru/article/2013.26.4/ MPM_2012_16_1_P04.pdf

RAR RUS 66-81 Ecole polytechnique fédérale de Lausanne (EPFL) Sharma

Lausanne, Switzerland

Kurukshetra University Sharma

Kurukshetra, India

IIT Roorkee Bhargava

India

Propagation of waves in micropolar thermoelastic solid with two temperatures bordered with layers or half-spaces of inviscid liquid The present study is concerned with the propagation of Lamb waves in a homogeneous isotropic thermoelastic micropolar solid with two temperatures bordered with layers or half-spaces of inviscid liquid subjected to stress free boundary conditions. The coupled thermoelasticity theory has been used to investigate the problem. The secular equations for symmetric and skew-symmetric leaky and nonleaky Lamb wave modes of propagation are derived. The phase velocity and attenuation coefficient are computed numerically and depicted graphically. The amplitudes of stress, microrotation vector and temperature distribution for the symmetric and skew-symmetric wave modes are computed numerically and presented graphically. Results of some earlier workers have been deduced as particular cases. micropolar thermoelastic secular equations phase velocity attenuation coefficient symmetric and skew-symmetric amplitudes https://mpm.spbstu.ru/article/2013.26.5/ MPM_2012_16_1_P05.pdf

RAR RUS 82-91 Karunya University Selvamani

India

Government Arts College (Autonomous) Ponnusamy

India

Extensional Waves in a Transversely Isotropic Solid Bar Immersed in an Inviscid Fluid Calculated Using Chebyshev Polynomials The extensional vibration in a homogeneous transversely isotropic solid bar immersed in an inviscid fluid is studied using the linearized, three-dimensional theory of elasticity. The equations of motion of solid bar and fluid are respectively formulated using the constitutive equations of a transversely isotropic cylinder and the constitutive equations of an inviscid fluid. The solution of the frequency equations are obtained by Chebyshev polynomial series using the geometric boundary conditions. The computed non-dimensional frequencies are presented in the form of dispersion curves for the material Zinc. To compare the model with exiting literature, the longitudinal vibration of cylindrical bar without fluid are obtained and they show good agreement. free vibration of transversely isotropic solid bar; elastic rods loaded with fluid; wave propagation in a cylinders immersed in a fluid; Chebyshev polynomials https://mpm.spbstu.ru/article/2013.26.6/ MPM_2012_16_1_P06.pdf

RAR RUS 92-100 Velalar College of Engineering and Technology Jananakumar

India

Loyola College Mani

India

Synthesis, growth and characterization of novel semiorganic nonlinear optical Potassium Boro-Oxalate (KBO) single crystals New semiorganic nonlinear optical (NLO) Potassium Boro-oxalate single crystals have been grown by Slow Evaporation technique at ambient temperature. The title compound has been subjected to single-crystal X-ray diffraction analysis to identify the unit cell parameters. Fourier Transform Infrared spectroscopic analysis was carried out on the grown sample to ascertain the fundamental functional groups. Optical absorption studies illustrate low absorption in the entire UV and Visible region. The crystal was subjected to TGA DTA analysis to find its thermal stability. The dielectric response of the crystal with varying frequencies was studied. The mechanical property of the grown crystals had been analyzed by Vickers’s microhardness method. The NLO property of the grown crystal has been confirmed by the Kurtz powder Second Harmonic Generation (SHG) test. semiorganic NLO Boro-oxalate (KBO) single crystals https://mpm.spbstu.ru/article/2013.26.7/ MPM_2012_16_1_P07.pdf