023287   Vidhya R D J;Jerome D S (Physics Dep, Loyola College, Chennai-600 034, Email: vidhyaaraj@gmail.com) : Structural and optical properties of copper doped zinc sulfide nanostructures using capping agents. Adv appl Res 2015, 7(1), 70-74.

Copper doped ZnS nanoparticles with different capping agents have been synthesized through chemical co-precipitation method. Polyvinylpyrrolidone (PVP), 1-thioglycerol and Trioctylphosphine oxide (TOPO) were used as capping agents. X-ray diffraction (XRD) studies revealed the average particle size of ZnS:Cu²⁺ with different capping agents to vary from 3 nm to 4 nm. Energy dispersive X-ray spectroscopy (EDAX) measurements confirmed the presence of Cu in the ZnS lattice. UV-Vis spectroscopy revealed blue shift for all the samples with respect to the bulk value. The band gap energy values were in the range of 4.29 eV to 4.86 eV. The blue shift was attributed to the quantum confinement effect. Room temperature photoluminescence (PL) spectrum of the ZnS:Cu²⁺ capped nanoparticles exhibited emission in the visible region with multiple peaks at an excitation wavelength of 250 nm.

023286   Thiam A;Sahin G;Moujtaba M A O E;Mbow B;Diouf M S;Ngom M I;Sissoko G (Physics Dep, Faculty of Sciences and Techniques, Univ of Cheikh Anta Diop, Dakar, Senegal, Email: gsissoko@yahoo.com) : Incidence angle effect on electrical parameters of a bifacial silicon solar cell illuminated by its rear side in frequency domain. Int J pure appl Sci Technol 2015, 30(1), 29-42.

The dynamic impedance Z (ω, θ) of bifacial Silicon solar cell under incidence angle, obtained by the ratio of the photocurrent density to the photovoltage V_Ph (ω, θ), is studied by use of Nyquist and Bode diagrams in order to determine electrical parameters.

13 illus, 2 tables, 19 ref

023285   Sharma R B;Verma S K;Arya S;Agarwal S (Physics Dep, Bipin Bihari (P.G.) College, Jhansi, Uttar Pradesh, Email: rbsharma.jhansi@gmail.com) : Fabrication of polystyrene based cobalt (II) and nickel (II) phosphate membranes: evaluation of membrane selectivity of metal ions. Flora Fauna 2016, 22(1), 59-68.

Bi-Ionic potential (BIP) values across both the membranes have been observed experimentally using various combinations of 1:1 electrolytes at different concentrations. On the other hand biionic potential (BIP) values have also been observed experimentally keeping the concentration of one electrolyte constant on one side of the membrane while varying the concentration of other electrolyte on other side of the membrane. The membrane conductance values in contact with single electrolyte at different concentrations have been measured experimentally to evaluate the selectivity of both the membranes. The theory developed by Sandblom and Eisenman based on non equilibrium thermodynamics has been utilized for the evaluation of membrane selectivity. The selectivity sequence of both the membranes was found K⁺ <62> Na⁺ <62> Li⁺.

4 illus, 6 tables, 32 ref

023284   Ramezani A H;Hantehzadeh M R;Ghoranneviss M; Darabi E (Plasma Physics Research Center, Science and Research Branch, Islamic Azad Univ, Tehran 16315-835, Email: ramezani.1972@gmail.com) : Structural modification of tantalum crystal induced by nitrogen ion implantation. Bull Mater Sci 2016, 39(3), 633-40.

This paper investigates the effect of nitrogen ion implantation on tantalum surface structure. In this experiment, nitrogen ions which had an energy of 30 keV and doses of 1x10¹⁷1x10¹⁷ to 10x10¹⁷10x10¹⁷ ions cm^-2 were used. X-ray diffraction analysis (XRD) was applied for both the metallic Ta substrate and the study of new structures that have been created through the nitrogen ion implantation. Atomic force microscopy (AFM) was also used tocheck the roughness variations prior to and also after the implantation phase. The experimental results show the formation of hexagonal tantalum nitride (TaN_0.43) in addition to the fact that by increasing the ion dose, the nitrogen atoms occupy more interstitial spaces in the target crystal. The nitride phase also seen for 3x10¹⁷3x10¹⁷ and 5x10¹⁷5x10¹⁷ ions cm^-2, while it disappeared for higher dose of 7x10¹⁷7x10¹⁷ and 1x10¹⁸1x10¹⁸ ions cm^-2. The FWHM of the dominant peak of tantalum nitride suggest the growth of the crystallite's size, which is in agreement with the AFM results ofthe grains.

6 illus, 6 tables, 36 ref

023283   Mould R A (Physics and Astronomy (Ret.) Dep, State Univ of New York at Stony Brook, Stony Brook, NY 11794-3800, Email: richard.mould@stonybrook.edu) : Quantum states of a conscious observer. J biol Engng Res Rev 2015, 2(1), 1-5.

Since the 1920s, probability has been extensively and successfully attributed to the square modulus of a quantum mechanical wave function. However, this has led to questions as to the nature of reality in quantum mechanics. Ambiguity arises because the notion of probability is tied to observations of the system rather than to variables of the system. To remedy this, we give probability an objective meaning rather than its classical-subjective meaning, and we identify it with a system variable that can generate a wave collapse-independent of an outside observer. Specifically, the definition of probability is related to changes in square modulus rather than to square modulus; and in addition, it is directly and causally linked to wave collapse. Square modulus is given no physical importance in this treatment. The traditional Born definition of probability is of course useful, but it is regarded here as inimical to physical understanding. The proposed treatment allows conscious persons (or cats) to be included in a quantum mechanical system without paradox, and it has microscopic as well as macroscopic applicability. It resolves many of the puzzling characteristics of quantum mechanics that are implicit in the Born (Copenhagen) interpretation.

4 ref

023282   Kim D W;Kim H S;Ahn S;Kim Y (Physics and Nanoscience Dep, College of Engineering, Sun Moon Univ, Asan-si, Chungnam 336-708, Republic of Korea, Email: yckim@eulji.ac.kr) : Advanced operation of microcolumn by introducing misalign corrector. Asian J Chem 2015, 27(11), 4247-50.

Authors introduced an advanced operation of a microcolumn to recover electron beam properties caused by electrodes misalign. The misalign corrector consists of a pair of electrodes and each electrode is divided by four even parts. We confirmed that by applying appropriate bias voltage to some parts of the corrector, electron beam trajectory could be adjusted. As a result, it is found that the corrector can be an useful electron unit to obtain fine electron beam properties.

9 illus, 12 ref

023281   Kazeminezhad I;Saadatmand S;Yousefi R (Nanotechnology Laboratory, Physics Dep, Shahid Chamran Univ of Ahvaz, Ahvaz, Iran, Email: Yousefi.ramin@gmail.com) : Effect of transition metal elements on the structural and optical properties of ZnO nanoparticles. Bull Mater Sci 2016, 39(3), 719-24.

Undoped and transition metal (TM)-doped ZnO nanoparticles (Zn_0.98X_0.02O-NPs, X= Mn, Cr, Co and Fe) were synthesized from a metal nitrate precursor and gelatin by a sol-gel method. The compounds were synthesized at calcination temperatures of 550°C for 6 h. The synthesized undoped/doped ZnO-NPs were characterized by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). XRD results indicated that the sample products were crystalline with a hexagonal wurtzite phase. SEM images showed the ZnO-NPs nearly spherical shapes and a non-uniform shape for doped ZnO-NPs. The crystalline development in the ZnO-NPs was investigated by X-ray peak broadening. The size-strain plot (SSP) method was used to study the individual contributions of crystallite sizes and lattice strain of the undoped and doped ZnO-NPs. The obtained results showed that strain ofthe NPs plays an important role in peak broadening; moreover, the mean crystalline size of the undoped and doped ZnO-NPs estimated from the SEM and the SSP method was highly inter-correlated. Finally, optical properties ofthe samples were studied by a UV-Vis spectrometer.

7 illus, 7 tables, 17 ref

023280   Kamoun O;Boukhachem A;Mrabet C;Yumak A; Petkova P;Boubaker K;Amlouk M (Unite de Physique des Dispositifs a Semi-conducteurs, Faculte des Scie, Universite de Tunis El Manar, 2092 Tunis, Tunisia, Email: abdelwaheb.boukhachem@laposte.net) : Effect of europium content on physical properties of In₂O₃ thin films for sensitivity and optoelectronic applications. Bull Mater Sci 2016, 39(3), 777-88.

In₂O₃:Eu thin films were successfully grown by spray pyrolysis. XRD studies showed that the films had In₂O₃ cubic structure with (004) preferential orientation and best crystal properties at 1.5% Eu doping level. Theoptical band gap energy decreased with Eu content around 4.1 eV. Urbach energy was of the order of 278 meV, it decreased with Eu content which indicates a decrease in the defects by doping. The dispersion of the refractive index was discussed. Raman spectroscopy showed the band positions corresponding to In₂O₃ cubic phase with a small shift related to europium incorporation within In₂O₃ matrix. PL measurements showed a large band which was located at 410 nm and related to the band-to-band transitions and other bands related to impurity levels. Finally, theelectric conductivity was investigated depending on the effect of temperature. Activation energy was found to range from 45 to 60 meV for films which were prepared with 1%Eu content.

13 illus, 11 tables, 79 ref

023279   Agrawal S L;Shukla P K;Sharma H;Singh C P; Tripathi D (SSI Laboratory, Physics Dep, A P S Univ, Rewa 486003, Madhya Pradesh) : Synthesis and characterization of nano CuInS₂ thin films for device applications. Bhartiya Vaigyanik Evam Audyogik Anusandhan Patrika 2016, 24(2), 123-7.

Present paper deals with synthesis and characterization of CuInS₂ thin films prepared through sol gel spray pyrolysis technique. During synthesis di-ethanolamine has been used as stabilizer for Indium acetate solution in 1-propanol while mono ethanolamine and ethylene glycol have been used in combination as stabilizing agent for Copper acetate solution in 2-propanol. The structural and optical properties of as deposited films have been explored in order to determine the optimum conditions for growth of CIS ternary compound semiconductor films. The physical and optical properties of the thin films synthesized at different substrate temperatures have been studied by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and UV-Visible spectroscopy. XRD analysis revealed formation of CuInS₂ phase along with that of Cu₉ In₄ as impurity. The crystallite size calculated from XRD data ranges from 45 to 63nm. SEM analysis have shown that film consist of homogeneous grains with sizes of about few hundred nanometers. Besides, formations of flower like structure and larger agglomerates have also been witnessed in the SEM examination. The energy band gap calculated from optical absorption spectra shows a blue shift on increasing the substrate temperature.

5 illus, 15 ref

021236   Yu Z H;Yu P;Yin B H;Wang Z Y (Ningbo Institute of Technology, Zhejiang Univ, Ningbo, China, Email: zaihe.yu@nit.zju.edu.cn) : Magnetic field induced bandgap in two dimensionakl magneto-optical photonic crystals. Indian J pure appl Phys 2016, 54(4), 263-8.

The photonic bandgap of magneto-optical (MO) photonic crystals (PhCs) induced by an external dc magnetic field is theoretically investigated with the plane-wave expansion method. The effect of PhC lattice shape, MO filling fraction and dc magnetic intensity on such type of bandgap has been studied. It is found that PhC with triangular lattice is superior to PhC with square lattice in term of bandgap width; thus, the one-way waveguide composed by the former PhC has a broader operation band. Moreover, there exists a certain value of external magnetic field at which the bandgap reaches a maximum. These results are found to be in agreement by finite element analysis of transmission property of one-way waveguides.

5 illus, 32 ref

021235   Thirumaran S;Earnest Jayakumar J (Physics Dep, Annamalai Univ, Annamalai Nagar-608 002, Email: thirumaran6 4@gmail.com) : Physico-chemical studies on some mono and disaccharides in aqueous media at 298.15 K. Indian J pure appl Phys 2016, 54(4), 284-92.

The present study divulges about the structure-making and breaking behaviour of some mono and disaccharides, viz., glucose, fructose, sucrose and maltose in aqueous N-N dimethylacetamide (DMA) at 298.15 K. The experimental values of density, viscosity and speed of sound are carried out on the ternary mixtures of water + DMA + mono and disaccharides at 298.15 K. The binary solvent mixture (water+ DMA) is prepared at different mass percentages, say at 0%, 10%, 20%, 30% and 40%. The mono and disaccharides under study are added with aqueous binary solvent under different molarities at normal atmospheric pressure. The volumetric, compressibility, partial transfer volume and viscometric studies have been carried out to explore the possible interionic interactions existing in the solution. The present study notices that disaccharides (sucrose, maltose) behave as an effective structure-maker in aqueous solution comparatively with mono saccharides (glucose, fructose).

7 illus, 5 tables, 17 ref

021234   Swarnkar H C;Arora G (Physics Dep, Faculty of Science, Paher Univ, Udaipur-313 022, Email: garora.gits@gmail.com) : Ab initio modeling of alkali metal chalcogenides using Sogga theory. Int J chem Sci 2015, 13(4), 1630-8.

The structural and electronic properties of some alkali metal chalcogenides namely Na₂Se, Na₂Te and K2Te has been presented by employing the linear combination of atomic orbitals method. In the present study, the local density approximation, generalized gradient approximation and second order GGA formalism in the framework of density functional theory were used. The calculated lattice constant is in good agreement with the available experimental and theoretical data. Electronic properties are discussed from the calculations of band structure and density of states. The band structure calculations implies direct band gap with conduction band minima and valence band maxima at Γ point for Na₂Se and Na₂Te, whereas indirect gap is obtained for K₂Te.

4 illus, 1 table, 26 ref

021233   Sumathi T (Physics Dep, Annamalai Univ, Tamil Nadu-608 002) : Molecular interaction studies on some binary organic liquid mixtures at 303K. Asian J biochem pharm Res 2015, 5(4), 200-8.

In the present study an attempt has been made to report the ultrasonic speed (u), viscosity (η) and density (p) of the various compositions of liquid mixtures of 1-pentanol with carbon tedrachloride, chloroform and dichloromethane at 303K. The density, ultrasonic velocity and viscosity for all binary mixtures were measured experimentally. Other acoustical parameters like adiabatic compressibility (β), intermolecular free length (L_f)free volume (V_f), internal pressure(π_i), acoustic Impedance(Z) and the excess values of some of the above parameters for the entire range of mole fraction of 1-pentanol are calculated and discussed.

3 tables, 30 ref

021232   Soheyli E;Shoar M H H;Parcham F (Faculty of Science, Sahand Univ of Technology, Sahand New Town, Tabriz, Islamic Republic of Iran, Email: e_soheily@sut.ac.ir) : Variation of electrical conductivity and activation energy in semiconducting glasses with combination of P₂O₅- CaO- MoO₃- Li₂O. Indian J pure appl Phys 2016, 54(3), 188-92.

In the present investigation, 40P₂O_{5_}xCaO (40-x)MoO_{3_}20Li₂O glasses with x=5, 10, 15, 20, 25 mol% were prepared by conventional melt quenching method. X-ray diffraction analysis was carried out to demonstrate the amorphous nature of prepared samples. Then, their dc conductivity (σ) was determined in the temperature range of 300-385 K by two-probe method. According to Mott theory, analysis of electrical properties has been made in the light of small polaron hopping (SPH) model and it was observed that the electrical conductivity increases with increase in temperature. The composition dependence of electrical conductivity and activation energy were also evaluated. It revealed that increasing the CaO content results in increase and decrease of activation energy and electrical conductivity, respectively. Moreover, conduction is ascribed to non-adiabatic hopping of small polaron.

6 illus, 2 tables, 38 ref

021231   Sinhamahapatra D;Haridas G;Pradeep Kumar; Ghodke A D;Tiwari M K;Hannurkar P R (Indus Operation & Accelerator Physics Design Div, Raja Ramanna Centre for Advanced Technology, Indore-452 013, Email: debasis@rrcat.gov.in) : Measurements of dose rate for 10-16 keV synchrotron X-ray photons at BL-16 beam line of Indus-2. Indian J pure appl Phys 2016, 54(4), 259-62.

Indus-2 is a 2.5 GeV electron synchrotron radiation source located at Raja Ramanna Centre for Advanced Technology (RRCAT), India. There is significant radiation exposure in the direct beam of synchrotron radiation due to its intense flux and low energy at synchrotron radiation beam line. In this paper, measurements of absorbed dose rate for mono chromatic synchrotron X-ray photon of energy ranging 10-16 keV is presented using various types of passive dosimeters, like CaSO4(Dy) TLDs, LiF :Mg,Ti (TLD-100), and Gafchromic film EBT-2 at microfocus X-ray fluorescence spectroscopy beam line (BL-16). The measured results are also compared with theoretically calculated values. It is observed that LiF :Mg,Ti (TLD-100), and Gafchromic film EBT-2 show 3-6 times more absorbed dose rates as compared to calculated values whereas CaSO₄(Dy) TLD shows 10-20 times more absorbed dose rates.

4 illus, 1 table, 8 ref

021230   Shelar R N;Patil A V;Dighavkar C G;Borse R Y (Physics Dep, L. V. H. College, Panchavati, Nashik, Maharashtra, Email: rajnshelar@gmail.com) : Comparative hydrogen bond studies of o-chlorophenol + cyclic/acyclic ether complexes by experimental and DFT methods. Int J chem Sci 2015, 13(4), 1765-76.

The Fourier transform infrared (FTIR) spectra of binary mixture of o-chlorophenol (OCP) with diphenyl ether (DPE), t-butyl methyl ether (TBME), tetrahydrofuran (THF) and 1,4 dioxane (DN) have been recorded over the entire composition range at room temperature in the regions 4000-400 cm^-1. The study indicated bonding interaction between the components of liquid mixtures. These spectra have been investigated in terms of various fundamental modes of vibration. The molecular structures of the binary complexes have been investigated by density functional theory (DFT) using B3LYP functional and 6-31 G (d) basis sets. Computed values have been analyzed and their characterization was made with the help of Gauss View visualization program utilizing the data obtained from Gaussian 03 W calculation. The results of the calculations are compared with the experimentally determined data.

6 illus, 2 tables, 22 ref

021229   Sharma G;Munish Kumar (Physics Dep, G B Pant Univ of Agriculture and Technology, Pantnagar-263 145, Email: munish_dixit@yahoo.com) : Effect of size with freedom of pressure and temperature for nanomaterials. Indian J pure appl Phys 2016, 54(4), 251-8.

A simple theoretical model is developed, which includes the effect of size, pressure and temperature on nanomaterials. The model is used to compute the variation of unit cell volume under different conditions of size, pressure and temperature of nanomaterials, viz., ε-Fe, Ni, Se and Zr. The results obtained are compared with the available experimental data. A good agreement is observed between model predictions and experimental data supporting the validity of the proposed model. Model predictions, reported in the absence of experimental data, may be interesting for the researchers engaged in the experimental studies of nanomaterials under varying conditions of size, pressure and temperature.

22 illus, 17 ref

021228   Shahbazi N;Jaleh B;Momeni A (Physics Dep, Bu-Ali Sina Univ, Hamedan, Iran, Email: bkjaleh@yahoo.com) : Mechanical properties of polycarbonate-TiO₂ nanocomposite film. Indian J pure appl Phys 2016, 54(4), 241-50.

The mechanical properties of polycarbonate-TiO₂ nanocomposite films have been investigated by conducting tensile tests and hardness measurements. The elastic modulus of the composite increased with increasing the weight fraction of particle, especially over 0.8 wt%. The X-ray diffraction results (XRD) show that the increase of strength is accompanied by decrease in intensity of amorphous polycarbonate and appearance of the peak of anatase. The theoretical models proposed by Guths-Smallwood, Einstein, Kerner and Cohen-Ishai are used but only the first model provided better results and is modified for the studied composite. The law of mixture is used to calculate the contribution coefficients of the constituents and the results of this modeling provided the acceptable precision. Peak stress and strain has been increased with increasing TiO₂ nanoparticles content while the stress and strain corresponding to the fracture point did in opposite. It is attributed to the influence of particles on the plastic weakening of the composite.

13 illus, 31 ref

021227   Rawat A;Singh P J (Physics Dep, M S J Govt College, Bharatpur-321 001, Email: anandrawat15oct@gmail.com) : Effect of temperature on dielectric property of polyvinylepyrrolidone/polyacrylamide blend films at microwave frequency. Indian J pure appl Phys 2016, 54(3), 170-6.

In this paper, dielectric constant (ε_r), dielectric loss (ε_i), loss tangent (tanδ), relaxation time (τ), ac conductivity (σ_ac), extinction coefficient (K) and refractive index (η) of polyvinylpyrrolidone (PVP), polyacrylamide (PAM) and their blend films have been studied in the temperature range 293-393 K at 9.01 GHz microwave frequency. The temperature and frequency dependent σ_ac of film samples is calculated using the dielectric parameters. The variation of ε_i, tanδ, K, σ_ac, η and τ showed a decreasing trend with increasing temperature. It is also observed that the temperature dependency of ε_r is insignificant at this frequency but its value for the film samples increases with the increasing concentration of PVP in the blend. The DSC measurements show miscible behaviour of PVP/PAM blends.

7 illus, 3 tables, 24 ref

021226   Rawat A K;Upadhyay T C (Physics Dep, HNB Garhwal Univ, Srinagar-246 174, Email: arvindsgfi@gmail.com) : Temperature dependence of dielectric constant and loss tangent in methyl ammonium aluminium alum. Indian J pure appl Phys 2016, 54(3), 183-7.

A model of pseudospin-lattice coupled mode for methyl ammonium aluminium alum (MASD) has been modified to include cubic and quartic phonon anharmonic interactions. With the help of double-time temperature dependent Green's function method and modified Hamiltonian, expressions for soft mode frequency, dielectric constant and loss tangent have been evaluated. By fitting model values of physical quantities in the theoretical expressions, temperature dependence of soft mode frequency, dielectric constant and loss tangent have been obtained and compared with experimental results of Pepinsky et al.¹⁵, which show a good agreement.

3 illus, 15 ref

021225   Rana V A;Chauhan K R;Menon S K (Physics Dep, Gujarat Univ, Ahmedabad-380 009, Email: varana@gujaratuniversity.ac.in ) : Dielectric absorption in dilute solutions of dibenzo-18-crown-6 in 1, 4-dioxane. Indian J pure appl Phys 2016, 54(3), 177-82.

Dielectric absorption of dibenzo-18-crown-6 (DB18C6) in solutions of 1,4-dioxane have been studied at 9.1 GHz frequency at three different temperatures 293.15, 303.15 and 313.15 K. A single frequency concentration variation method of Gopalkrishna was used to calculate relaxation time (δ_GK). Thermodynamical parameters, like free energy (ΔF), enthalpy (ΔH) and entropy (ΔS) of activation for the dielectric relaxation have been determined using dielectric data. Static permittivity, refractive index and density of liquid solutions are also measured at 293.15 K. Dipole moment of DB18C6 is determined using Gopalkrishna and Guggenheim's method.

4 illus, 3 tables, 29 ref

021224   Putrevu S A;Chaladi S K (ECE Dep, Gitam Univ, Visakhapatnam, Andhra Pradesh, Email: shivaaditya96@gmail.com) : Generation of electricity using sound. Curr Trends Technol Sci 2015, 4(3), 504-6.

Life is intricately woven with many necessities. Electrical energy is no less than the life source itself, hence, tops the list source of priorities. Acute shortage of this energy in every field-from the domestic to the dynamic frontiers of growth and development- is hampering the functioning of progressive modules. "SOUND" a source which engulfs every phase of life and environment always goes waste once produced. This inspired the thought of looking at possibilities of generating electrical energy from sound energy. This source is 'easily available and renewable?. Tapping this source and converting it into a productive one will directly contribute to a sound pollution free environment too. The main idea is to produce the electrical energy from sound energy to overcome the acute shortages of power supply in various fields of life. The basic reason to take sound as the input source is that a lot of sound energy is being wasted around us which is a "RENEWABLE" source of energy that is produced ample in nature.

6 ref

021223   Pinjari R K;Aldar B A;Burange N M;Bhosale C H (Physics Dep, Smt Kasturbai Walchand College, Sangli-416 416, Email: nmburange@gmail.com) : Structural and electrical properties of y(Ni_0.7Co_0.2Cd_0.1Fe₂O₄) + (1-y)Ba_0.9Sr_0.1TiO₃ magnetoelectric composite. Indian J pure appl Phys 2016, 54(4), 279-83.

Magnetoelectric (ME) composites of ferrite and ferroelectric phase with y(Ni_0.7Co_0.2Cd_0.1Fe₂O₄) + (1-y)Ba_0.9Sr_0.1TiO₃ with y=0.15, 0.30 and 0.45, respectively were prepared by standard double sintering ceramic method. The constituent phases, i.e., ferrite and ferroelectric phase presence were confirmed by X-ray diffraction pattern. Scanning electron micrographs were studied to understand microstructure of the prepared samples. The dielectric constant (ε) and loss tangent (tanδ) were measured as a function of frequency and also function of temperature at the fixed frequencies 1, 10, 100 kHz and 1 MHz. The AC conductivity was studied to understand conduction mechanism.

7 illus, 1 table, 21 ref

021222   Negi S;Rana M P S;Gautam S K;Singh R G;Singh F;Ramola R C (Physics Dep, HNB Garhwal Univ, Badshahi Thaul Campus, Tehri Garhwal-249 199, Email: sandhyanegi@gmail.com) : Structural and optical modification of Ga-doped zinc oxide thin films induced by thermal annealing. Indian J pure appl Phys 2016, 54(4), 236-40.

Ga doped ZnO (ZnO:Ga) thin films were prepared by the sol-gel spin coating technique. The films are annealed at different temperature varying from 500°C to 900°C in controlled oxygen environment. The effects of annealing temperature on structural, morphological and optical properties of films are investigated. The XRD results show that all deposited films are textured along the (101) direction and exhibits wurtzite phase of ZnO. The AFM images show that the grain size of ZnO films increased with increasing annealing temperature. Red shifting (band gap decreases) of the optical band gap is also observed on increasing the temperature. The observations are explained on the basis of stress and grain growth induced by thermal annealing.

5 illus, 1 table, 35 ref

021221   Murugavel S;Vijayakumar S;Nagarajan S; Ponnuswamy A (NO, Thanthai Periyar Government Institute of Technology, Vellore-632 002, Email: smurugavel27@gmail.com) : Crystal structure and DFT studies of 4-(1-benzyl-5-methyl-1H-1, 2, 3-triazol-4-yl)-6-phenylpyrimidin-2-amine. Indian J pure appl Phys 2016, 54(3), 199-208.

The title compound (1) 4-(1-benzyl-5-methyl-1H-1,2,3-triazol-4-yl)-6-phenylpyrimidin-2-amine (C₂₀H₁₈N₆) was synthesized and structurally characterized by elemental analysis, ¹H NMR, ¹³C NMR and single crystal X-ray diffraction. The compound crystallizes as a colourless needle shaped in the monoclinic system, space group C 2/c with cell constants: a = 18.6636(6) angstrum, b = 9.8655(4) angstrum, c = 19.5249(7) angstrum, α = γ = 90.0°, β = 107.900(2)°, V = 3421.0(2) angstrum³, Z = 8. The molecular conformation is stabilized by an intra-molecular C-H...N hydrogen bond, which generates an S(6) ring motif. In the crystal, molecules are linked into one-dimensional infinite chains along c-axis by N-H...N hydrogen bond and C-H... π interactions involving the benzene ring attached to the triazole ring as an acceptor. These chains are alternately connected along a-axis by centro-symmetrically π--π interactions [ring centroid (triazole) ring centroid (pyrimidine) distance = 3.721 (1) angstrum and ring centroid (pyrimidine)...ring centroid (benzene ring attached to pyrimidine ring) distance = 3.825 (1) angstrum] forming a two-dimensional supra molecular network. The molecular geometry was also optimized using density functional theory using (DFT/B3LYP) method with the 6-311G(d,p) basis set and compared with the experimental data. Mulliken population analyses on atomic charges and HOMO-LUMO energy levels of the title compound have been calculated. The charge energy distribution and site of chemical reactivity of molecules were obtained by mapping electron density iso-surface with electrostatic potential surfaces. The thermo dynamical properties of the title compound at different temperature have been calculated and corresponding relations between the properties and temperature have also been obtained.

9 illus, 7 tables, 45 ref

021220   Kanagasabapathy K;Gowri Shanmugapriya G; Vetrivel S;Rajasekaran R (NO, A A Government Arts College, Villupuram-605 602, Email: kksaba98@gmail.com) : Growth, spectral, thermal, mechanical, linear and nonlinear optical studies of divalent metal ions doped zinc tris-thiourea sulphate single crystals. Indian J pure appl Phys 2016, 54(3), 193-8.

Zinc tris-thiourea sulphate (ZTS) and divalent metal ions (Cd²⁺ and Ni²⁺) doped zinc tris-thiourea sulphate materials are synthesized from aqueous solution and single crystals are grown from aqueous solution by slow evaporation technique. The unit cell parameters of the grown crystals are evaluated by single crystal X-ray diffraction analysis. The powder X-ray diffraction patterns are recorded and indexed for further confirmation of crystalline nature of grown crystals. The presence of functional groups in the grown crystals has been confirmed by FTIR analysis. The incorporation of cadmium and nickel ions entered into ZTS crystals is confirmed from SEM-EDX analysis. TGA/DTA thermal analyses revealed that the materials have good thermal stability. Mechanical behaviour have been studied using Vicker's microhardness measurements. UV-visible transmission spectra have been recorded in the spectral range 200-900 nm to find the cut-off wavelength and optical band gap E_g of grown crystals in non-linear applications. The nonlinear optical properties of pure and doped ZTS crystals were confirmed by Kurtz Perry powder method using Nd:YAG laser source.

7 illus, 2 tables, 14 ref

021219   Jeyavijayan S (Physics Dep, Kalasalingam Univ, Krishnakoil-625 126, Email: jaya_vijayan83@yahoo.com) : FTIR, FT-Raman spectra and DFT analysis of 3-methyl-4-nitrophenol. Indian J pure appl Phys 2016, 54(4), 269-78.

The FTIR and FT-Raman spectra of 3-methyl-4-nitrophenol (MNP) have been recorded in the regions 4000-400 cm^-1 and 3500-50 cm^-1, respectively. Utilizing the observed FTIR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of the compound have been carried out. The optimum molecular geometry, harmonic vibrational frequencies, infrared intensities and Raman scattering activities, have been calculated by density functional theory (DFT/B3LYP) method using 6-31+G(d,p) and 6-311++G(d,p) basis sets. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared and Raman spectra of MNP is also reported based on total energy distribution (TED). The calculated HOMO and LUMO energies show that the charge transfers occur within the molecule.

4 illus, 6 tables, 24 ref

021218   Fan Q;Wei Q;Chai C;Yan H;Zhang M;Zhang Z; Zhang J;Zhang D (State Key Discipline Lab of Wide BandGap Semiconductor Technology, School of Microelectronics, Xidian Univ, Xi'san 717 071, China, Email: weiaqun@163.com) : Structural, anisotropic and thermodynamic properties of boron carbide: First principles calculations. Indian J pure appl Phys 2016, 54(4), 227-35.

The structural, mechanical, electronic properties of the potentially superhard P4₂/mnm-BC have been investigated by using the density functional theory with the ultrasoft psedopotential scheme in the frame of the generalized gradient approximation and the local density approximation. The elastic constants, bulk modulus, shear modulus, Young's modulus, B/G ratio and Poisson's ratio for BC at various pressures have been investigated. The elastic anisotropy under pressure from 0 GPa to 100 GPa has been studied. The elastic anisotropy of Young's modulus, shear modulus, and Poisson's ratio show that P4₂/mnm-BC exhibits a large anisotropy and the elastic anisotropy increases with increasing pressure. Electronic structure studies show that P4₂/mnm-BC is a conductor. Using the quasi-harmonic Debye model, the thermodynamic properties of P4₂/mnm-BC have also been investigated. The variation of the thermal expansion, isothermal bulk modulus, Debye temperature, Gruneisen parameter, and heat capacity with pressure and temperature have been obtained systematically.

7 illus, 2 tables, 39 ref

021217   Ehemba A K (Lab of Semiconductors and Solar Energy, Physics Dep, Faculty of Science and Technology, Univ Chekh Anta Diop, Dakar, Senegal, Email: ehambaalain@yahoo.fr) : Influence of CuInSe₂ and Cu(In, Ga)Se₂ thin layer thickness on the electric parameters of the solar cell. Curr Trends Technol Sci 2015, 4(3), 535-41.

In this paper we propose to study the effect of CuInSe₂ and Cu(In, Ga)Se₂ layers thickness on the electric parameters of the solar cells. The studied characteristics are resistance series Rs, resistance shunt Rsh, the short circuit current density Jsc, the open circuit voltage Voc, the form factor FF and the conversion efficiency η. We operate the characterization of these cells by using the wxAMPS (Analysis of Microelectronic and Photonic Structures) and Matlab which are recognized characterization softwares. This study enables us to take note on the one hand adequate thickness of thin film which would give a more powerful cell and on the other hand the capital interest to pass from the base in CuInSe₂ to the base in Cu(In,Ga)Se2. We find that the electric parameters of the cell vary according to the thickness of the base and that the suitable thickness is 2.5μm as well for Cu(In, Ga)Se₂ than for CuInSe₂. For the same thickness Cu(In, Ga)Se₂ presents better electric parameters than CuInSe₂.

12 illus, 1 table, 12 ref

021216   Diallo W;Mbengue N;Diagne M;Mbow C;Ba B (Laboratoires des Semi-conducteurs et d'enertie stolaire, Physique Dep, Faculte des Sciences et Techniques, Univ Cheikh Anta Diop de Dakar, Senegal, Email: walydiallo85@yahoo.fr) : Ultras TPV conversion efficiencies depending on the energy gap of the materials used and the source emission temperature. Curr Trends Technol Sci 2015, 4(3), 528-31.

The interest on thermophotovoltaic cells (TPV) is their ability to generate electricity from heat sources. They are made of semiconductor materials which are classified according to the width of their band gap. Those with smaller band gaps, so capable of absorbing large wavelength radiation such as infrared, offer better prospects for greater extension of solar energy, especially in hot countries. This article is a study of the ultras TPV conversion efficiencies depending on the energy gap of the materials used and the source emission temperature. This study focused generally on the cells at high, medium and low band gap.

11 illus, 8 ref

021215   Debnath P (NO, NIT, Agartala, Email: prasenjit1001@yahoo.com) : Why the speed of light is an absolute constant: Because god does not play dice. Curr Trends Technol Sci 2015, 4(3), 532-4.

At the beginning of twentieth century, two physical theories completely changed the way we traditionally perceived space and the physical time. These are the Einstein's the general theory of relativity and the Quantum Mechanics. About one hundred years passed, still we are trying to unify these two theories with some other necessary ingredients to have the theory of everything that describes all possible everything in the Universe. The general theory of relativity predicts that space-time is not flat; the distribution of matter and energy curves or wraps the space-time. Bodies try to follow the straight line path but because space-time is not flat, the body's path appears to be bent. It predicts that gravity is the distortion of space-time due to nonuniform distribution of matters and energy. It had been discovered that light does not reach to observer instantaneously; rather it travels at a certain constant speed of 186,000 miles per second or 300,000 km per second which is independent of source and observer movement. No matter at what speed the observer or the source is moving, the speed of light is always the same, an absolute constant it is. How can this be true? The general theory of relativity also predicts that the universal speed limit is the speed of light, which means that nothing can exceed the speed of light, an observation can check the validity of the statement, if anything can come out of the Black holes, it must be greater than the velocity of light as light cannot escape from Black holes. Now, what are the causes of the speed of light to be an absolute constant? Is that the Universe is very fine tuned to diminish the uncertainty principle to have one and unique history and future? The independency of source or observer and an absolute constancy of the speed of light support the unique history and unique future concept. Thus, the prediction of the determinism is absolutely valid because God does not play dice.

3 illus, 22 ref

021214   Debnath P (NO, NIT, Agartala, Email: prasenjit1001@yahoo.com) : What is the physical time: An energy, An interaction, A particle or an effect of energy-Particle duality?. Curr Trends Technol Sci 2015, 4(3), 525-7.

What the physical time is all about? Is it energy? Or is it an interaction? Or is it a rather simply particle? Or is it an effect of energy-particle duality? Is it possible that the goal of theoretical physics related to the physical time can be achieved in the not-too-distant future? At the beginning of the Nineteenth century, it was believed that the continuum mechanics could explain everything of the Universe. All we need to measure some parameters or coefficients like viscosity, conductivity, elasticity etc. The interactions such as electromagnetism and gravitation are of long range which means that the fields produced by a large number of matter particles can all add up to give a field which can be detected on a macroscopic scale. And this is the reason that the first theories developed for them: the gravity by Sir Isaac Newton in the seventeenth century and electromagnetism by Maxwell in the nineteenth century. However, these both theories are incompatible to each other because the Newtonian theory of gravitation is invariant if the whole system such as the Universe is given a uniform velocity, whereas the Maxwell theory of electromagnetism defines a preferred velocity- the velocity of light (300,000 km/second). At the end, it was Newtonian theory of gravity that had to be modified to make compatible with the invariance property of Maxwell theory of electromagnetism. This was achieved by Einstein's general theory of relativity on gravity, which was proposed in 1915. The problem arose when one tried to apply such classical theories, like Newtonian theory or Maxwell theory, to construct the model of an atom. These theories predict that the electrons radiate electromagnetic waves while orbiting around the nucleus very like the Earth orbiting the Sun in the solar system. These electromagnetic waves would carry away energy and would cause the electrons to spiral into the nucleus, producing the collapse of the atomic structure. This problem was overcome by what is called the greatest achievement of the theoretical physics in the twentieth century: the discovery of the quantum theory which basically based on the uncertainty principle that predicts that the quantities such as velocity and position cannot be measured accurately simultaneously, the more accurate we measure one, the less accurate will be the other. In the case of the atom, this means that in the lowest energy state of an electron, it cannot be at rest in the nucleus because, in that case, its position would be completely defined (in the nucleus) and its velocity would be exactly defined (to be zero in the nucleus). So, because of the uncertainty principle, the electron cannot radiate energy in the form of electromagnetic waves, because there is no lower energy state for electron to go to.

23 ref

021213   Debnath P (NO, NIT, Agartala, Email: prasenjit1001@yahoo.com) : Nothing puzzles me like the physical time: A two dimensional approach of the physical time. Curr Trends Technol Sci 2015, 4(3), 507-9.

The physical time itself was considered eternal, in a sense that it had existed for ever and will exist forever too. In the context of the Newtonian mathematical model, in which the physical time was an infinitely single lined, it was independent of what was happening in the physical Universe that we live in. However, in 1915, a completely new mathematical model was proposed by Einstein: the general theory of relativity. The general theory of relativity combines the physical time dimension with the three dimensions of space to form what is called the space-time. The general theory of relativity incorporates the effect of gravitational force by saying that the distribution of energy and matter in the physical Universe wraps and distorts the space-time itself. So, according to the theory of general relativity, the physical time is not flat at all and objects in this Einstein's space-time try to follow the path of a straight line, but because of the space-time is wraps to be curved, their paths appear bent. I propose a mathematical model of the physical time having two-dimensional approach in which there is an imaginary physical time direction at the right angles to ordinary real time line. The proposed model can completely determine the history in imaginary time from the real ordinary physical time and vice versa. The magnitude of the imaginary time will tell the change of rate at which the real physical time with respect to the rate of physical time in the absolute vacuum as reference.

3 illus, 25 ref

021212   Choudhary S;Sengwa R J (Dielectric Research Lab, Physics Dep, J N V Univ, Jodhpur-342 005, Email: rjsengwa@rediffmail.com) : Structural dynamics and ionic conductivity of amorphous type plasticized solid polymer electrolytes. Indian J pure appl Phys 2016, 54(3), 159-69.

Poly(ethylene oxide) and poly(methyl methacrylate) blend based solid polymer electrolytes consisting of lithium triflate as a dopant ionic salt with varying concentration of propylene carbonate as plasticizer have been prepared by classical solution cast and ultrasonic-microwave irradiated solution cast methods. The X-ray diffraction study confirms that these electrolyte films have predominantly amorphous morphology. Dielectric relaxation spectroscopy in the frequency range 20 Hz - 1 MHz reveals that the complex dielectric spectra of the electrolytes have dispersion at high frequencies corresponding to polymer chain segmental relaxation process in the solid ion-dipolar complexes, whereas the electrode polarization relaxation process dominates at low frequencies. Significant changes in the polymer chain dynamics and dielectric parameters of the electrolytes are observed with change of plasticizer concentration and the sample preparation methods. Relatively enhanced polymer chain segmental dynamics, ordered ion-dipolar cooperativity and favourable ion conductive paths increase three times the ionic conductivity of 15 wt% PC polymeric electrolyte film prepared by ultrasonic-microwave irradiated method as compared to that of the classical solution cast method. The ionic conductivity and dielectric relaxation time have the Arrhenius temperature dependence characteristics of their same values of activation energies. Results infer that the ions transportation in the solid complexes of these electrolytes is predominantly governed by polymer segmental dynamics.

5 illus, 2 tables, 42 ref

021211   Chaudhary S;Choudhary M K (Mathematics Dep, Malaviya Nationakl Institute of Technology, Jaipur-302 017, Email: d11.santosh@yahoo.com) : Heat and mass transfer by MHD flow near the stagnation point over a stretching or shrinking sheet in a porous medium. Indian J pure appl Phys 2016, 54(3), 209-17.

A comprehensive numerical study of a steady two-dimensional stagnation point flow towards a heated linearly stretching or shrinking sheet in a porous medium immersed in viscous, incompressible and electrically conducting fluid in the presence of a uniform transverse magnetic field is presented. Using similarity transformation, the governing boundary layer partial differential equations are converted into non-linear ordinary differential equations and solved by Runge-Kutta fourth order method along with shooting technique. Some significant features of the flow and heat transfer in terms of velocity and temperature for various values of the governing parameters like, stretching or shrinking parameter, Prandtl number, permeability parameter, magnetic parameter and Eckert number are analyzed and presented through graphs while skin-friction coefficient and Nusselt number are shown numerically. Results of shear stress and heat transfer rate are also compared with the results of previous researchers.

10 illus, 3 tables, 43 ref

020408   Verma B R;Patel S K (Physics Dep, Govt S.G.G. PG College, Krurd (Dhamtari)-493 663, Email: bhunesh.verma@gmail.com) : Theoretical studies on light-emitting diodes. J pure appl ind Phys 2016, 6(1), 42-9.

The Light-emitting diode, frequently known as LED, is a semiconductor p-n junction device that under proper forward-biased conditions can emit external spontaneous radiation in the ultraviolet, visible and infrared regions of the spectrum. The main function of an LED is to convert electrical energy into light energy in the visible part of the spectrum for display and illumination purposes. The present paper reports that the theoretical studies on light-emitting diodes and its applications in lighting system technology.

^iia4 illus, 6 ref

020407   Veklich A N;Lebid A V;Time-nova T A (Faculty of Radio Physics, Electronics and Computer Systems, Taras Shevchenko National Univ of Kyiv, Volodymyrs'ka 64, 01033 Kyiv, Ukraine, Email: tania.tmenova@gmail.com) : Spectroscopic data of W I, Mo I and Cr I spectral lines: selection and analysis. J Astrophys Astr 2015, 36(4), 589-604.

Plasma of electric arc discharges between composite Cu-W, Cu-Mo and Cu-Cr electrodes in argon flow and their spectra were studied by optical emission spectroscopy. Since values of oscillator strengths for W I, Mo I and Cr I presented in various sources are significantly different, selection of spectroscopic data for these elements (particularly oscillator strength) was expected to be useful for plasma diagnostics. The Boltzmann plot method was used as a tool for the selection of appropriate spectral lines and their spectroscopic data. The main result of the paper is W I, Mo I and Cr I spectral lines and spectroscopic data recommended for diagnostics of plasma with such metal impurities.

15 illus, 24 ref

020406   Sen R;Saha M;Das Chowdhury S;Shekhar N K; Nishat Kumar;Pal D;Ghosh A;Dhar A;Pal A;Pal M (Fiber Optics and Photonics Div, CSIR-Central Glass & Ceramic Research Institute, 196, Raja S.C. Mullick Road, Kolkata-700 032, Email: maitreyee.cgcri@gmail.com) : High power fiber lasers: Fundamentals to applications. Sci Cult 2015, 81(11-12), 319-26.

***

12 illus, 27 ref

020405   Selyaev V P;Nurlybaev R E;Neverov V A; Aidarova S B;Zhuginisov M T;Murzagulova A A (NO, , KazNTU Named After K.I. Satpayev, Satpayev St. 22, 050 013, Almaty, Kazakhstan, Email: bagdat777_87@mail.ru) : Nanostructured irregularity study by X-ray small-angle scattering. Int J chem Sci 2015, 13(3), 1421-9.

X-ray small-angle scattering and structural nanometer level irregularities of dispersed natural diatomite particles of some Aktobe region deposits, Kazakhstan. The pore structure parameters and fractal characteristics of scatter formations have been determined. Fractal dimensions of particles from the Middle Volga region diatomite deposits, the Russian Federation, are given below.

4 illus, 2 tables, 15 ref

020404   Saravanakumar M;Agilan S;Muthukumarasamy N; Rukkumani V (Physics Dep, SVS College of Engineering, Coimbatore, Tamil Nadu, Email: saranspectra@gmail.com) : Structural and ferromagnetic investigation of the size effects in pure and Co doped SnO₂ nano particles. Int J chem Sci 2015, 13(2), 605-12.

Structural, micro structural and magnetic properties of pure and Co doped SnO₂ nano particles with different concentration (2%, 4% and 6%) have been studied. These nano particles synthesized by chemical precipitation method using cobalt nitrate hexahydrate Co(NO₃)₂.6H₂O and tin chloride (SnCl₂.2H₂O), respectively. X-ray diffraction (XRD), high transmission transmission electron microscopy (HRTEM), room temperature magnetization measured using Vibrating Sample Magnetometer (VSM) were performed to study the crystal structure, morphology and magnetic properties of Co doped SnO₂. The X-ray diffraction patterns show that all the specimen have tetragonal rutile structure without any extra phase. It reveals polycrystalline nature with prominent peaks along (110), (101), (200) and (211) planes. All the samples are nano crystalline with particle size lying in the ra.nge of 5-25 nm calculated by DS formula. HRTEM results depict the formation of spherically shaped and and particle size lies in range of 16-25 nm. SnO₂ nano particles after doped Co show ferromagnetic behavior at room temperature the coercive field (Hc) values are found to be increased with increase in Co doping concentrations.

3 illus, 21 ref

020403   Sakthivel S;Boopathi A (Thin Film Physics and Nano Science Lab, PG and Research Physics Dep, Rajah Sefoji Govt. College, Thanjavur-613 005, Email: sakthivel.sunmugam@yahoo.com) : Characterization study of coducting polymer PANI-GO nano composite thin film supercapacitor. J pure appl ind Phys 2016, 6(1), 34-41.

Polyaniline-graphene oxide (PANI-GO) composites were obtained through in-situ chemical polymerization of aniline in a suspension of graphene oxide with different weight percentage. The synthesised nano composite materials were thin layer coated on glass and Al foil substrate. The PANI-GO nano composite thin films were studied by characterization of structural, functional groups analysis by XRD, FTIR spectroscopes. The optical absorption characterization of nano composite thin films by UV-Vis spectroscopy and supercapacitor performances of electrochemical analysis by using cyclic voltamatric (CV) technique. The result showed that structural study of XRD analysis showing as a synthesised nano composite as a amorphous nature and two small peaks present in spectral line, the optical absorption as a very small absorption in UV-Vis spectral regions of PANI-GO thin films, the electrochemical cyclic voltamatric analysis calculated specific capacitance value of PANI-GO nano composite thin film as 470.87 Fg^-1.

4 illus, 26 ref

020402   Sakthivel S;Boopathi A (Thin Film Physics and Nano Science Lab, PG and Research Physics Dep, Rajah Serfoji Govt. College, Thanjavur-613 005, Email: sakthivel.sunmugam@yahoo.com) : Structural and morphological characterizations of poly (P-Phenylene vinylene) thin film by spin coating application of polymer LED. J pure appl ind Phys 2016, 6(1), 29-33.

The conjugated polymer of Poly (p-phenylene vinylene) and its derivatives are most studied material in applications of numerous photonic devices such as organic solar cells, organic light emitting diodes (OLEDs). In this study we gave prepared PPV thin film in glass substrate at deposition of spin coating technique for rotational speed of 3000 rpm in vacuum condition. After that PPV thin film were characterized by structural characterization of X-ray diffraction spectroscopy reveal that film as a fully amorphous nature of bands present and surface morphological characterization of scanning electron microscopy clearly showing porous structure particles presenting on the substrate.

7 illus, 8 ref

020401   Rosato J (Aix-Marseille Univ, CNRS, PIIM UMR 7345, F-13397 Marseille Cedex 20, France, Email: joel.rosato@univ-amu.fr) : Radiative transfer reconsidered as a quantum kinetic theory problem. J Astrophys Astr 2015, 36(4), 605-11.

Author revisit the radiative transfer theory from first principles approach, inspired from quantum kinetic theory. The radiation field is described within the second quantization formalism. A master equation for the radiation density operator is derived and transformed into a balance relation in the phase space, which involves nonlocal terms owing to radiation coherence. In a perturbative framework, we focus on the lowest order term in h-expansion and show that the radiation coherence results in an alteration of the photon group velocity. An application to the formation of hydrogen lines in stellar atmospheres is performed as an illustration.

^iia15 ref

020400   Rao D V S;Muraleedharan K;Muralidharan R (Defence Metallurgical Research Lab, DRDO, Hyderabad, Email: duggi@dmrl.drodo.in) : Solidstate lighting. Sci Cult 2015, 81(11-12), 290-7.

Lighting is an integral part of human life. Globally, about 15% of the generated power is spent for the lighting applications. In this context, the recent advances in 'solid state lighting (SSL)' are very important to promote energy savings and reduce green house gas emissions. This article presents an overview of advancements in SSL with focus on GaN light emitting diode (LED), its impact on energy savings and relevance to India.

4 illus, 7 ref

020399   Radeep N R;Pradeep N;Varadharaja P;Gayathri Devi S S (Nano Science and Technology Dep, Mount Carmel College, Bengaluru) : ZnO nanorod grown on glass substrate by thermal oxidation route using muffle furnace technique. J pure appl ind Phys 2016, 6(1), 1-6.

Zinc Oxide Nanorods were prepared by using Zn metal thin films prepared by Electron Beam evaporation method. For the growth of the nanorods prepared Zinc Films were Oxidize at different temperature using muffle furnace at constant time. The Zinc Oxide (ZnO) nanorods surface morphology was studied by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The length of the Nanorods was estimated to be urn and diameter less than 100 nm. The atomic elements of Zn and O are measured by Energy Diffraction Spectroscopy (EDAX).

3 illus, 1 table, 21 ref

020398   Ponnusamy P M;Agilan S;Muthukamarasamy N (Physics Dep, SNS College of Technology, Coimbatore, Tamil Nadu, Email: surya.ponnusamy@gmail.com) : Simple route synthesis of Cr-doped NiO nanoparticles and their characterisation studies. Int J chem Sci 2015, 13(2), 683-92.

Nano scale NiO and Cr doped NiO nanoparticles (NPs) have been prepared by simple chemical co-precipitation method. The structure, morphology, band gap energy and magnetic properties of the synthesized samples have been examined by X-ray diffraction, SEM, HRTEM, UV absorption and VSM, respectively. The insertion of Cr ions into NiO NPs gives significant changes in structural and magnetic properties. The crystalline size of Cr-doped NiO was calculated and it is around 20 nm. The UV absorption study shows strong absorption peak around 300 nm. The magnetic property was studied using Vibrating Sample Magnetometer (VSM) and NiO NPs exhibit super paramagnetic behavior, which differs from bulk form whereas Cr-doped NiO NPs magnitization curve recorded the appearance of diamagnetic behaviour and was found suitable for spin value applications.

10 illus, 1 table, 19 ref

020397   Mustafina S;Mikhailova T;Miftakhov E (Physics and Mathematics Dep, Bashkir State Univ, Sterlitamak City, Lenin Avenue, 37, Postal Index-453 103, Russian Federation, Republic of Bashkortostan, Email: Mustafina_SA@mail.ru) : Mathamatical study of the butadiene-styrene copolymerization product by the Monte Carlo method. Int J chem Sci 2015, 13(2), 849-56.

Statistical approach to the description of mathematical model of butadiene-styrene copolymerization process has been considered in this paper. The approach is based on the Monte Carlo method. The mathematical model allows researching properties of the product of copolymerization and predicting values of molecular characteristics depending on conversion and carrying out the calculation of copolymer's molecular weight distribution.

4 illus, 10 ref

020396   Mishra L P;Mishra L K (Physics Dep, Magadh Univ, Bodh Gaya-824 234, Email: muphysicslkm@gmail.com) : Theoretical evaluation of temperature dependent thermal conductivity of carbon nanotube. Int J chem Sci 2015, 13(2), 672-82.

Using the theoretical formalism of J. Hone (Dekker encyclopedia of Nano science and Nanotechnology, 2004), we have evaluated the temperature dependent thermal conductivity of isolated SWNT, 2D-graphene sheet, 3D-graphite and single MWNT. From these evaluations, it shows that the thermal properties of carbon nanotubes are dominated by phonons. The results also show 1-D quantization of phonon band structure. Our theoretical results indicate that nanotube composite materials may be useful for thermal management applications.

6 tables, 25 ref

020395   Mihajlov A A;Sreckovic V A;Sakan N M (Institute of Physics, Univ of Belgrade, P.O. Box 57, 11001, Belgrade, Serbia, Email: sreckovicvladimir@gmail.com) : Inverse Bremsstrahlung in astrophysical plasmas: The absorption coefficients and gaunt factors. J Astrophys Astr 2015, 36(4), 635-42.

The electron-ion inverse Bremsstrahlung is considered here as a factor of the influence on the opacity of the different stellar atmospheres and other astrophysical plasmas. It is shown that this process can be successfully described in the frames of cut-off Coulomb potential model within the regions of the electron densities and temperatures. The relevant quantum mechanical method of the calculation of the corresponding spectral coefficient processes is described and discussed. The results obtained for the plasmas with the electron densities from 10¹⁴ cm^-3 to 2 . 10¹⁹ cm^-3 and temperatures from 5 . 10³ K to 3 . 10⁴ K in the wavelength region 100 nm <60> λ <60> 3000 nm are presented. Also, these results can be of interest for different laboratory plasmas.

^iia5 illus, 14 ref

020394   Mihajlov A A;Sreckovic V A;Ignjatovic L M; Klyucharev A N;Dimitrijevic M S;Sakan N M (Institute of Physics, Univ of Belgrade, P.O. Box 57, 11001, Belgrade, Serbia, Email: sreckovicvladimir@gmail.com) : Non-Elastic processes in atom Rydberg-atom collisions: Review of state of art and problems. J Astrophys Astr 2015, 36(4), 623-34.

Incur previous research, it has been demonstrated that inelastic processes in atom Rydberg-atom collisions, such as chemi-ionization and (n-n') mixing, should be considered together. Here we will review the present state-of-the-art and the actual problems. In this context, we will consider the influence of the (n-n')-mixing during a symmetric atom Rydberg-atom collision processes on the intensity of chemi-ionization process. It will be taken into account H(1s) + H*(n) collisional systems where the principal quantum number is n <62> <62>1. It will be demonstrated that the inclusion of (n-n') mixing in the calculation, influences significantly on the values of chemi-ionization rate coefficients, particularly in the lower part of the block of the Rydberg states. Different possible channels of the (n-n')-mixing influence on chemi-ionization rate coefficients will be demonstrated. The possibility of interpretation of the (n-n')-mixing influence will be considered on the basis of two existing methods for describing the inelastic processes in symmetrical atom Rydberg-atom collisions.

^iia2 illus, 3 tables, 19 ref