016162   Home D (Centre for Astroparticle Physics and Space Science, Bose Institute, Kolkata-700 091, Email: dhome@jcbose.ac.in ) : Facets of the leggett-garg inequality: some recent studies. Curr Sci 2015, 109(11), 1980-6.

In this article, we begin by briefly reviewing the basics of the Leggett-Garg inequality which is a temporal analogue of Bell's inequality, based on the notions of realism and noninvasive measurability. This is followed by outlining the core ideas and key results of two different types of recent studies related to the Leggett-Garg inequality, bringing out its ramifications concerning unsharp measurements and quantum key distribution respectively.

30 ref

016161   Hayat T;Waqas M;Shehzad S A;Alsaedi A (Mathematics, Quaid-i-Azam Univ 45320, Islamabad-44000, Pakista, Email: ali_qau70@yahoo.com) : Stretched flow of carreau nanofluid with convective boundary condition. Pramana J Phys 2016, 86(1), 3-17.

The steady laminar boundary layer flow of Carreau nanofluid over a stretching sheet is investigated. Effects of Brownian motion and thermophoresis are present. Heat transfer is characterized using convective boundary condition at the sheet. The governing partial differential equations are reduced into a set of nonlinear ordinary differential equations through suitable transformations. Results of velocity, temperature and concentration fields are computed via homotopic procedure. Numerical values of skin-friction coefficient, local Nusselt and Sherwood numbers are computed and discussed. A comparative study with existing solutions in a limiting sense is made.

11 illus, 5 tables, 41 ref

016160   Hasegawa Y (Atominstitut, Technische Univ Wien (TU-Wien), A-1020 Wien, Austria, Email: hasegawa@ati.ac.at) : Uncertainty relation and quantum cheshire-cat: studied with neutron polarimeter and interferometer. Curr Sci 2015, 109(11), 1972-9.

Fundamental phenomena in quantum mechanics are investigated by the use of matter-wave optics: in the studies neutron polarimeter and interferometer are exploited. Successive measurements of 1/2-spin of the neutron are carried out to test the error-disturbance uncertainty relation. The experimental results confirm the violation of Heisenberg's original reciprocal relation for measurement error and disturbance, and the validity of the reformulated generally valid relation. In addition, as an example of a counterfactual phenomenon of quantum mechanics, interferometric experiment is performed to observe the so-called quantum Cheshire-Cat: a particle and its magnetic moment travel through the interferometer along different beam paths. The results of our experiment suggest that, with suitable pre- and post-selections, neutrons travel along one of the arms of the interferometer, while their spin is located in the other arm.

5 illus, 45 ref

016159   Gupta P D (Physics and Astrophysics Dep, Delhi Univ, Delhi-110 007, Email: patrick@srb.org.in) : Gravity, Bose- Einstein condensates and gross- pitaevskii equation. Curr Sci 2015, 109(11), 1946-50.

We explore the effect of mutual gravitational interaction between ultra-cold gas atoms on the dynamics of Bose-Einstein condensates (BEC). Small-amplitude oscillation of BEC is studied by applying variational technique to reduce the Gross-Pitaevskii equation, with gravity included, to the equation of motion of a particle moving in a potential. According to our analysis, if the s-wave scattering length can be tuned to zero using Feshbach resonance for future BEC with occupation numbers as high as ≈10^{20, there exists a critical ground state occupation number above which the BEC is unstable, provided that its constituents interact with a 1/r3 gravity at short scales.}

17 ref

016158   Govender M;Maharaj S D;Mkhize L;Lortan D B (Astrophysics and Cosmology Research Unit, School of Mathematics, Statistics and Computer Science, Univ of Kwazulu-Natal, Private Bag X54001, Durban 4000, South Africa, Email: govenderm43@ukzn.ac.za) : Thermal evolution of the kramer radiating star. Pramana J Phys 2016, 86(1), 49-58.

The Kramer radiating star uses the interior Schwarzschild solution as a seed solution to generate a model of dissipative collapse. We investigate the thermal behaviour of the radiating star by employing a causal heat transport equation. The causal temperature is explicitly determined for the first time by integrating the transport equation. We further show that the dissipation of energy to the exterior space-time renders the core more unstable than the cooler surface layers.

4 illus, 37 ref

016157   Goswami S (NO, Physical Research Laboratory, Navrangpura, Ahmedabad-380 009, Email: sruba@prl.res.in) : Neutrinos in the time of higgs. Pramana J Phys 2016, 86(2), 395-405.

In this paper, the recent progress in the determination of neutrino oscillation parameters and future prospects have been discussed. The tiny neutrino masses as inferred from oscillation data and cosmology cannot be explained naturally by the Higgs mechanism and warrant some new physics. The latter can be connected to the Majorana nature of the neutrinos which can be probed by neutrinoless double beta decay (0 v β β). The paper also summarizes the latest experimental results in 0 v β β and discusses some implications for the left-right symmetric model which could be a plausible new physics scenario for the generation of neutrino masses.

7 illus, 1 table, 37 ref

016156   Ghosh M;Ghoshal P;Goswami S;Raut S K (NO, Physical Research Laboratory, Navrangpura, Ahmedabad-38 0 009, Email: monojit@prl.res.in) : Evidence for leptonic CP phase from NOvA, T2K and ICAL. Pramana J Phys 2016, 86(2), 387-93.

Phenomenon of neutrino oscillation is now well understood from the solar, atmospheric, reactor and accelerator neutrino experiments. This oscillation is characterized by a unitary PMNS matrix which is parametrized by three mixing angles (θ₁₂, θ₂₃ and θ₁₃) and one phase (δ_CP) known as the leptonic CP phase. Neutrino oscillation also involves two mass squared differences: the solar mass square difference (Δ₂₁ = m2/2-m2/1) and the atmospheric mass square difference (Δ₃₁ = |m2/3-m2/1|). Though there is already significant amount of information about the three mixing angles, the CP phase is still unknown. Apart from the CP phase, one should also know what is the true nature of the neutrino mass hierarchy, i.e., normal (m₃ <62> m₁: NH) or inverted (m₁ <62> m₃: IH) and what is the true octant of θ₂₃, i.e., lower (θ₂₃ <60> 45°: LO) or higher (θ₂₃ <62> 45°: HO). The long-baseline experiments (LBL) have CP sensitivity coming from the appearance channel (v_μ→v_e). On the other hand, atmospheric neutrinos are known to have negligible CP sensitivity. In this work, we study the synergy between the LBL experiment NO?A, T2K and the atmospheric neutrino experiment ICAL@INO for obtaining the first hint of CP violation in the lepton sector. We find that due to the lack of knowledge of hierarchy and octant, CP sensitivity of NO? A/T2K is poorer for some parameter ranges. Addition of ICAL data to T2K and NO?A can exclude these spurious wrong-hierarchy and /or wrong-octant solutions and cause a significant increase in the range of ^{δCP values for which a hint of CP violation can be achieved. Similarly, the precision with which δCP can be measured also improves with the inclusion of ICAL data.}

4 illus, 15 ref

016155   Garg I (Physics Dep, Panjab Univ, Chandigarh-160 014, Email: ila@prl.res.in) : SUSY see-saw and NMSO(10)GUT unflation after BICEP2. Pramana J Phys 2016, 86(2), 315-23.

Supersymmetric see-saw slow roll inflection point inflation occurs along a MSSM D-flat direction associated with gauge invariant combination of Higgs, slepton and right-handed sneutrino at a scale set by the right-handed neutrino mass M_v^{c <126> 106-1013. The tensor to scalar perturbation ratio r<126> 10-3 can be achieved in this scenario. However, this scenario faced difficulty in being embedded in the realistic new minimal supersymmetric SO(10) grand unified theory (NMSO(10)GUT). The recent discovery of B-mode polarization by BICEP2, changes the prospects of NMSO(10)GUT inflation. Inflection point models become strongly disfavoured, as the trilinear coupling of SUSY see-saw inflation potential gets suppressed relative to the mass parameter favoured by BICEP2. Large values of r ≈ 0.2 can be achieved with super-Planck scale inflaton values and mass scales of inflaton ≥ 10 13 GeV. In NMSO(10)GUT, this can be made possible with an admixture of heavy Higgs doublet fields, i.e., other than MSSM Higgs field, which are present and have masses of order GUT scale.}

4 illus, 1 table, 16 ref

016154   Garg A (Physics and Astronomy Dep, Northwestern Univ, Evanston, Illinois-60208, USA, Email: agarg@northwestern.edu) : Experimental tests of macrorealism: an assessment. Curr Sci 2015, 109(11), 1958-64.

The macrorealistic inequality of Leggett and Garg is reviewed, along with a recent experiment that aims to test it.

3 illus, 20 ref

016153   Fall M F M;Ngom M I;Sahin M S D G;Thiam A; Sissoko G (Cheikh Anta Diop, Faculty of Sciences and Techniques, Physics Dep, Dakar, Senegal, Email: gsissoko@yahoo.com) : Photo thermal response study of a white biased bifacial silicon solar cell under magnetic field. Int J pure appl Sci Technol 2015, 31(2), 26-39.

In this paper, we present a photo thermal response study, for a back side illuminated bifacial silicon solar cell under magnetic field by thermal dynamic impedance representations through Nyquist and Bode diagrams.

13 illus, 15 ref

016152   Efimov A;Sukharev V;Ivanov V;Lizunova A (Physical and Quantum Electronics Dep, Moscow Institute of Physics and Technology, Dolgopurdny, Russia, Email: efimov.aa@mipt.ru) : Influence of parameters of spark discharge generator on dimensional characteristics of synthesized TiO₂ nanoparticles. Oriental J Chem 2015, 31(4), 2285-90.

A multi-spark discharge generator was used for the synthesis of TiO₂ nanoparticles. The nanoparticles were obtained in the form of fractal-like agglomerates with an average size of 30-60 nm consisting of primary spherical nanoparticles with a diameter of about 7-8 nm according to TEM measurements. We found that changing the operating parameters of the generator - energy of the capacitor (2 to18 J), repetition frequency of discharge (0.5 to 4 Hz) and velocity of airflow (1.4 to 5.4 m/s) changed only the size of the agglomerates while the size of the primary nanoparticles stayed the same.

5 illus, 20 ref

016151   Dhuria M (Therotical Physics Div, Physical Research Laboratory, Ahmedabad-380 009, Email: mansi.dhuria87@gmail.com) : Phenomenological implications of D3/ D7 (reversed) μ-split-like supersymmetry scenario. Pramana J Phys 2016, 86(2), 245-53.

Phenomenological model is presented which can be obtained as a local Swiss-Cheese Calabi-Yau string-theoretic compactification with a mobile D3- and fluxed stacks of wrapped D7-branes. It provides a natural realization of (reversed) μ-split-like supersymmetry wherein the squarks, sleptons, gauginos, higgsino and one of the Higgs doublets are very heavy while with some fine tuning, it is possible to obtain another light Higgs of mass 125 GeV. We discuss the role of the heavy quarks /sleptons and the light Higgs in (i) obtaining long-lived gluinos (a natural consequence of split SUSY), (ii) verifying that the NLSP decays to the gravitino LSP respects the BBN constraints with the lifetime of the LSP (gravitino) coming out to be of the order or larger than the age of the Universe, (iii) getting gravitino relic abundance of around 0.1 and (iv) obtaining electronic EDM close to the experimental upper bounds.

1 table, 13 ref

016150   Dev S;Gautam R R;Singh L;Gupta M (Physics Dep, School of Sciences, H.N.B.G. Central Univ, Srinagar-246 174, Email: gautamrrg@gmail.com) : Two-texture zeros and near-maximal atmospheric neutrino mixing angle. Pramana J Phys 2016, 86(2), 379-86.

Authors study the implications of a large value of the effective Majorana neutrino mass for a class of two-texture zero neutrino mass matrices in the flavour basis. We find that these textures predict near-maximal atmospheric neutrino mixing angle in the limit of large effective Majorana neutrino mass. We present the symmetry realization of these textures using the discrete cyclic group Z₃. It is found that the texture zeros realized in this work remain stable under the renormalization group running of the effective neutrino mass matrix at one-loop level.

2 illu, 2 tables, 22 ref

016149   Dattagupta S (NO, , Visva-Bharati, Santiniketan-731 235, India, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru-, Email: sushantad@gmail.com ) : Coherence versus decoherence- a few illustrative examples. Curr Sci 2015, 109(11), 1951-7.

The interplay of coherence and decoherence is a vexing issue in contemporary condensed matter physics, quantum optics and quantum information theory. We present an overview of this important topical subject, in terms of three different paradigms, in which the 'noisy' effect of the environment on small quantum subsystems is analysed.

5 illus, 24 ref

016148   Dass N D H (Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad-500 075, Email: dass@tifrh.res.in) : Three results on weak measurements. Curr Sci 2015, 109(11), 1965-71.

Three recent results on weak measurements are presented. They are: (i) repeated measurements on a single copy cannot provide any information on it and further, that in the limit of very large such measurements, weak measurements have exactly the same characteristics as strong measurements; (ii) the apparent non-invasiveness of weak measurements is illusory and they are no more advantageous than strong measurements even in the specific context of establishing Leggett-Garg inequalities, when errors are properly taken into account, and, finally, (iii) weak value measurements are optimal, in the precise sense of Wootters and Fields, when the post-selected states are mutually unbiased with respect to the eigenstates of the observable whose weak values are being measured. Notion of weak value coordinates for state spaces are introduced and elaborated.

11 ref

016147   Das D;Arvind (Physical Sciences Dep, Indian Institute of Science Education and Research Mohali, Manauli-140 306, Email: debmalya@iisermohali.ac.in) : Quantum state estimation using weak measurements. Curr Sci 2015, 109(11), 1939-45.

It explores the possibility of using 'weak measurements' without 'weak value' for quantum state estimation. Since for weak measurements the disturbance caused during each measurement is small, we can rescue and recycle the state, unlike for the case of projective measurements. We use this property of weak measurements and design schemes for quantum state estimation for qubits and for Gaussian states. We show, via numerical simulations, that under certain circumstances, our method can outperform the estimation by projective measurements. It turns out that ensemble size plays an important role and the scheme based on recycling works better for small ensembles.

3 illus, 41 ref

016146   Daraam B;Hassan F;Shwya A (Physics Dep, College of Science, Mustansiriyah Univ, Iraq, Email: abbasalwan@hotmail.com) : Density functional theory investigation for H₂-siver interactions. Int J pure appl Sci Technol 2015, 29(2), 73-83.

Density functional theory has been carried out for H₂ molecule, Ag_n and Ag_nH₂ nanoclusters, (n=4, 5, 6, 7). Optimization plus frequency, B3LYP, 3-21G basis sets has been investigated at the ground state level. Point group symmetry determined for H₂ molecule, Ag_n and Ag_nH₂ nanoclusters. Binding energy has been computed for Ag_nH₂ nanoclusters, Ag7H₂ nanocluster has lower binding energy (0.0329 eV) and this point out that Ag7H₂ nanocluster is more binding than the other Ag_nH₂ nanoclusters. Hardness and Softness has been calculated for H₂ molecule, Ag_n and Ag_nH₂ nanoclusters. Hardness Softness Acid Base (HSAB principle) has been applied to know behaviour of H₂ molecule, Ag_n and Ag_nH₂ nanoclusters. Electronegativity and electrophilicity have been computed for H₂ molecule, Ag_n and Ag_nH₂ nanoclusters. Dipole moment has been evaluated for H₂ molecule, Ag_n and Ag_nH₂ nanoclusters. Also average polarizability has been calculated for H₂ molecule, Ag_n and Ag_nH₂ nanoclusters. Finally density of state (DOS) has been investigated for Ag_n and Ag_nH₂ nanoclusters, Ag₅ posses DOS raises as compared with other pure silver nanoclusters, but Ag₅H₂ has DOS rises as compared with all other nanoclusters. All calculations have been investigated by using Gaussian 09 software package.

2 illus, 6 tables, 35 ref

016145   Choi K Y;Mandal S;Shin C S (NO, Asia Pacific Centre for Theroetical Physics, Pohang, Gyeongbuk-790 784, Republic of Korea, Email: smandal.phy@mnit.ac.in) : Quasar polarization with ultralight (pseudo-) scalars. Pramana J Phys 2016, 86(1), 169-83.

Recently, it was shown that the absence of circular polarization of visible light from quasars severely constrains the interpretation of axion-like particles (ALPs) as a solution for the generation of linear polarization. Furthermore, the new observation of linear polarization in radio wavelength from quasars, similar to the earlier observation performed in the optical bands, makes the ALPs scenario inconsistent with at least one of the two observations. In this study, we extend this scenario by including more scalars. We find that the effects from scalar and pseudoscalar neutralize each other, thereby suppressing the circular polarization, while preserving consistent linear polarization, as observed in both the visible and radio wave bands.

5 illus, 29 ref

016144   Boroun G R;Esfandyari E (Physics Dep, Razi Univ, Kermanshah-67149, Iran, Email: grboroun@gmail.com) : Next-to-leading order corrections to the valon model. Pramana J Phys 2016, 86(1), 77-86.

A seminumerical solution to the valon model at next-to-leading order (NLO) in the Laguerre polynomials is presented. We used the valon model to generate the structure of proton with respect to the Laguerre polynomials method. The results are compared with H1 data and other parametrizations.

5 illus, 14 ref

016143   Bilankohi S M (Physics Dep, Payame Noor Univ, Iran, Email: sara.mohammadibilankohi@gmail.com) : Optical scattering and absorption characteristics of silver and silica/silver core/shell nanoparticles. Oriental J Chem 2015, 31(4), 2259-63.

The optical properties of spherical silver and silica/silver nanoparticles are calculated using classical electrodynamics. The wavelength corresponding to maximum extinction shifts to longer wavelengths as the size of the nanoparticle is increased. The influence of higher-order multipoles is evident for large nanoparticles, making the spectra more complex. When the shell thickness of a core/shell particle is decreased, the plasmon resonance shifts to longer wavelengths. This red shift is accompanied by an increase in peak intensity. A model for core/shell nanoparticles is presented to investigate surface coverage effects. This model can be used to interpret the optical properties during the growth process or to examine the effects of shell defects, uneven growth, and surface roughness. The preliminary results for low surface coverage show an increase in extinction as the number of surface particles is increased. The peak position for the array of surface particles matches the resonant wavelength for an isolated spherical nanoparticle with a radius equal to half the shell, size, as expected for the uncoupled limit.

6 illus, 14 ref

016142   Bhawandeep U;Beri S B (Physics Dep, Panjab Univ, Sector-14, Chandigarh-160 014, Email: bhawanuppal11@gmail.com) : Z<. Pramana J Phys 2016, 86(2), 487-91.

Area-normalized angular distributions in events containing a Z^{0 boson and a jet, using the electron decay mode, are presented. The data samples correspond to 5 fb-1 of proton-proton collisions at sv √s = 7 TeV, collected by the CMS detector. Events in which there is a Z boson and at least one jet, with a jet transverse momentum threshold of 30 GeV /c and absolute jet rapidity less than 2.4, are selected for this analysis. We compare our measurements with a next-to-leading order perturbative QCD calculation and two generators that combine tree-level matrix element calculations with parton showers.}

2 illus, 11 ref

016141   Banerjee R (NO, S.N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata-700 098, Email: rabin@bose.res.in) : Anomalus hydromdynamics in two dimensions. Pramana J Phys 2016, 86(2), 453-8.

New approach is presented to discuss two-dimensional hydrodynamics with gauge and gravitational anomalies. Exact constitutive relations for the stress tensor and charge current are obtained. Also, a connection between response parameters and anomaly coefficients is discussed. These are new results which, in the absence of the gauge sector, reproduce the results found by the gradient expansion approach.

9 ref

016140   Bajc B (NO, J. Stefan Institute, Jamova Cesta 39, 1000 Ljubljana, Slovenia, Email: borut.bajc@ijs.si) : Interplay between grand unification and supersymmetry in SU(5) and E₆. Pramana J Phys 2016, 86(2), 231-44.

Some aspects of minimal supersymmetric renormalizable grand unified theories are reviewed here. These include some constraints on the model parameters from the Higgs and light fermion masses in SU(5), and the issues of symmetry breaking, doublet-triplet splitting and fermion masses in E₆.

3 illus, 23 ref

016139   Badran H A;Al-Ahmad A Y;Alihassan Q M;Emshary C A (Physics Dep, College of Education for Pure Sciences, Basrah Univ, Basrah, Iraq, Email: badran_hussein@yahoo.com) : Determination of optical constants and nonlinear optical coefficients of violet 1-doped polycinyl alcohol thin film. Pramana J Phys 2016, 86(1), 135-45.

The optical properties of Violet 1-doped polyvinyl alcohol (PVA) have been investigated using Wemble and Didomenico (WD) method. The optical constants such as refractive index n, the dispersion energy E_d, the oscillation energy E₀, the lattice dielectric constant ε_∞, light frequency dielectric constant ε₀ and the ratio of carrier concentration to the effective mass N/m* have been determined using reflection spectra in the wavelength range 300-900 nm. The single- beam Z-scan technique was used to determine the nonlinear optical properties of Violet 1:polyvinylalcohol (PVA) thin film. The experiments were performed using continuous wave (cw) laser with a wavelength of 635 nm. The calculated nonlinear refractive index of the film, n₂ = -2.79 x 10-7 cm^{2/W and nonlinear absorption coefficient, β = 6.31 x 10-3 cm /W. Optical limiting characteristics of the dye-doped polymer film was studied. The result reveals that Violet 1 can be a promising material for optical limiting applications.}

10 illus, 2 tables, 39 ref

016138   Awasthi R L (NO, Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad-211 019, Email: awasthi.r6@gmail.com) : Prospects of experimentally reachable beyond standard model physics in inverse see-saw motivated SO(10) GUT. Pramana J Phys 2016, 86(2), 223-9.

Grand unification theories based on SO(10) gauge group have been at the centre of attraction to beyond Standard Model phenomenology. The SO(10) gauge symmetry may pass through several intermediate symmetries before breaking to Standard Model. Therefore some higher symmetries may occur at the experimentally reachable scales. This feature flourishes easily in non-supersymmetric models compared to supersymmetric ones. We find that certain breaking chains give tremendous predictions for the physics being explored at various particle physics experiments. Explanation to neutrino masses through TeV scale inverse see-saw is the driving theme of the models studied.

2 illus, 42 ref

016137   Aulakh C S (Physics Dep, Panjab Univ, Chandigarh-160 014, Email: aulakh@iisermohali.ac.in) : New minimal SO(10) GUT: a theory for all epochs. Pramana J Phys 2016, 86(2), 207-21.

The supersymmetric SO(10) theory (NMSO(10)GUT) based on the 210+126+126 Higgs system proposed in 1982 has evolved into a realistic theory capable of fitting the known low energy particle physics data besides providing a dark matter candidate and embedding inflationary cosmology. It dynamically resolves longstanding issues such as fast dimension five-operator mediated proton decay in SUSY GUTs by allowing explicit and complete calculation of crucial threshold effects at M_SUSY and M_GUT in terms of fundamental parameters. This shows that SO(10) Yukawas responsible for observed fermion masses as well as operator dimension-five-mediated proton decay can be highly suppressed on a 'Higgs dissolution edge' in the parameter space of GUTs with rich superheavy spectra. This novel and generically relevant result highlights the need for every realistic UV completion model with a large /infinite number of heavy fields coupled to the light Higgs doublets to explicitly account for the large wave function renormalization effects on emergent light Higgs fields. The NMSGUT predicts large-soft SUSY breaking trilinear couplings and distinctive sparticle spectra. Measurable or near measurable level of tensor perturbations - and thus large inflaton mass scale - may be accommodated within the NMSGUT by supersymmetric see-saw inflation based on an LHN flat direction inflaton if the Higgs component contains contributions from heavy Higgs components. Successful NMSGUT fits suggest a renormalizable Yukawon ultraminimal gauged theory of flavour based upon the NMSGUT Higgs structure.

1 illus, 2 tables, 45 ref

016136   Aminikhah H;Pournasiri F;Mehrdoust F (Applied Mathematics Dep, School of Mathematical Sciences, Guilan Univ, P.O. Box-1914, P.C. 41938, Rasht, Iran, Email: hossein.aminikhah@gmail.com) : Novel effective approach for systems of coupled schrodinger equation. Pramana J Phys 2016, 86(1), 19-30.

Schrodinger equations arise in modelling various physical and engineering problems. In this paper, we introduce a new homotopy perturbation method (NHPM) to improve the accuracy and computational efficiency of the homotopy perturbation method (HPM). We show that this technique enables one to determine the exact solution of the system of Schrodinger equations. Several illustrative examples are given to demonstrate the effectiveness of this method.

25 ref

016135   Ajala O A;Waheed A A;Sangoniyi S O (Pure and Applied Mathematics Dep, Ladoke Akintola Univ of Technology, Ogbomoso, Nigeria) : MHD free convection reacting variable viscosity power-law flow on a porous plate. Int J pure appl Sci Technol 2015, 31(2), 51-64.

Authors considered the flow of a viscous fluid flowing in a two dimensional channel between two parallel plates placed at y=h and y=-h. The momentum equation considered was non-dimensionalised after the introduction of buoyancy and porosity term. We are able to showed that the solution exist and unique. The effects of introduction terms were displayed graphically.

6 illus, 8 ref

016134   Ahmad N;Tripathi V K;Ahmad M;Rafat M (Applied Sciences and Humanities Dep, Galgotias College of Engineering and Technology, Greater Noida-201 306, Email: nafis.jmi@gmail.com) : Oscillating two-stream instability of laser wakefield-driven plasma wave. Pramana J Phys 2016, 86(1), 157-67.

The laser wakefield-driven plasma wave in a low-density plasma is seen to be susceptible to the oscillating two-stream instability (OTSI). The plasma wave couples to two short wavelength plasma wave sidebands. The pump plasma wave and sidebands exert a ponderomotive force on the electrons driving a low-frequency quasimode. The electron density perturbation associated with this mode couples with the pump-driven electron oscillatory velocity to produce nonlinear currents driving the sidebands. At large pump amplitude, the instability grows faster than the ion plasma frequency and ions do not play a significant role. The growth rate of the quasimode, at large pump amplitude scales faster than linear. The growth rate is maximum for an optimum wave number of the quasimode and also increases with pump amplitude. Nonlocal effects, however reduce the growth rate by about half.

2 illus, 22 ref

015115   Zhai Y;Wang Q;Li X;Chen X;Huang Q;Xia J (School of Electronic Science and Engineering, Southeast Univ, Nanjing 210096, China, Email: northrockwql@seu.edu.cn) : Transmission properties of sub-wavelength metallic tapered grating with different-shaped walls. J Optics 2015, 44(1), 20-5.

Sub-wavelength metallic tapered gratings with different-shaped slit walls are proposed in this research report. The transmission properties of the gratings have been investigated by finite difference time domain (FDTD) method. The simulation indicates that the transmission spectra strongly depend on the shapes of the slit walls. For TM-polarized light with normal incidence, the transmission coefficient and the bandwidth in the tapered gratings with the concave-parabolic slit walls are larger compared with the gratings with the convex-parabolic walls. For TE polarized light with normal incidence, the simulated results are reverse. In the visible range, the valley positions or peak positions of the transmission spectra are almost unchanged for all the gratings with different-shaped slit walls. The interaction of the electromagnetic (EM) waves on the slit walls with impendence match model has also been proposed in this paper.

6 illus, 44 ref

015114   Zeng Z F;Liu J G (Basic Dep, Jiangxi Vocational and Technical College of Communication, Jiang Xi-330 013, China, Email: 395625298@qq.com) : Solving (3+1)-dimensional generalized BKP equations by the improved (G'/G)-expansion method. Indian J pure appl Phys 2015, 53(11), 713-17.

An improved (G'/G)-expansion method and variable separation method have been studied in the present paper. By employing the improved (G'/G)-expansion method, new soliton solutions for the (3 + 1) dimensional BKP equations have been derived. Some interesting physics structure with the help of symbolic computation has been studied.

4 illus, 26 ref

015113   Yang C;Shang Z J;Wang Z;Peng H;Tang X D;Li B; Chen Y (Key Laboratory of Polar Materials and Devices, Ministry of Education, East China Normal Univ, Shanghai 200241, China, Email: bli@ee.ecnu.edu.cn) : Investigation of nonlinear optical properties in bismuth nanospheres suspensions. J Optics 2015, 44(1), 7-11.

Bismuth nanospheres with diameters below 100 nm were synthesized. Optical nonlinearities of Bi nanospheres suspensions have been investigated by Z-scan technique in the condition of non-resonant excitation with femtosecond laser, and the third order nonlinear refractive index was obtained for Bi nanospheres. These samples also exhibit optical limiting ability through the refraction optical limiting detection. The results indicate that the nonlinear absorption and scattering can be ignored for the solvent ethanol and the Bi nanospheres suspensions present obvious nonlinear refraction properties under the non-resonant femtosecond laser pulse excitation after excluded the nonlinear absorption and nonlinear scattering.

4 illus, 2 tables, 15 ref

015112   Xu X;Pan X;Jin J;Song N;Zhang Z (School of Instrument Science and Opto-electronics Engineeering, Beihang Univ, Beijing, China, Email: xuxiaobin@buaa.edu.cn) : Investigation of polarization nonreciprocity's effect on the performance of scale factor in closed-loop fiber optical gyroscope. J Optics 2015, 44(1), 30-5.

The performance of scale factor is generally thought to be just dependent on the stability of wavelength, the area of fiber coil, and half-wave voltage of modulator, but its dependence on polarization nonreciprocity (PNR) in a closed-loop fiber optical gyroscope (FOG) is investigated here theoretically and experimentally. A model is established to obtain the primary waves and the main secondary waves existing in the FOG, based on which their interference intensities are obtained and utilized for closing loop. The simulation result reveals that a bias error caused by PNR depends on input angle velocity, so scale factor error arises as a result. The phase difference between the primary and secondary waves, which is induced by different optical paths they have experienced in birefringent segments, affects PNR's contribution to scale factor error and may make PNR cause large nonlinearity of scale factor, even "dead zone" under small input angle velocity. The experiment verifies the analyzing and simulation results.

7 illus, 7 ref

015111   Ved Prakash;Diwan R K;Niyogi U K (NO, Shriram Institute for Industrial Research, 19 Univ Road, Delhi-110 007, Email: ved.chem@gmail.com) : Characterization of synthesized copper oxide nanopowders and their use in nanofluids for enhancement of thermal conductivity. Indian J pure appl Phys 2015, 53(11), 753-8.

Three copper oxide nanopowders were synthesized by three different copper precursors, CuSO₄.5H₂O, Cu(NO₃)₂.3H₂O and (CH₃COO)Cu.H₂O and characterized by FTIR, X-ray diffraction (XRD), thermal conductivity and cyclic voltammetry. These parameters were compared with the sample of CuO nano-powder procured from Sigma Aldrich. The positions of FTIR and XRD peaks are nearly similar for the synthesized CuO nanopowders as well as Sigma Aldrich CuO nanopowder. Substantial enhancement of thermal conductivity (60%) has been observed in nanofluid prepared from CuO nanopowder obtained from (CH₃COO) Cu.H2O precursor. The electrochemical behaviour of acidic solution of all CuO nanopowders indicates Cu^{2+/0 and Cu0/2+ electrode reaction and irreversible redox nature.}

3 illus, 3 tables, 23 ref

015110   Umadevi M;Kesavasamy R;Ponnusamy V;Priya N S; Ratina K (Physics Dep, SVS College of Engineering, Coimbatore, Email: devuma55@gmail.com) : Intermolecular interactions in ternary liquid mixtrues by ultrasonic measurements. Indian J pure appl Phys 2015, 53(12), 796-803.

Excess adiabatic compressibility (β^{E), excess free length (L_fE), excess free volume (V_fE) and excess internal pressure (π_iE) have been investigated from density, ultrasonic velocity and viscosity measurements for three ternary mixtures of methyl benzoate + cyclohexane + 1-propanol, methyl benzoate + cyclohexane + 1-butanol, methyl benzoate + cyclohexane +1-pentanol and methyl benzoate + cyclohexane + 1-hexanol at 303, 308 and 313 K and atmospheric pressure, respectively over the entire range of composition. From the experimental data, adiabatic compressibility (β), free length (L_f), free volume (V_f), internal pressure (π_i), have been calculated. The results are discussed in terms of the molecular interactions between the components of the mixture.}

4 illus, 3 tables, 27 ref

015109   Timothy Peace Balasingh S;Rabi Raja Singh I; Mohamathu Rafic K;Ebenezer Suman Babu S;Paul Ravindran B (Radiotherapy Dep, Christian Medical College, Vellore, Tamil Nadu, Email: tim_peace@yahoo.com) : Determination of dosimetric leaf gap using amorphous silicon electronic portal imaging device and its influence on intensity modulated radiotherapy dose delivery. J med Phys 2015, 40(3), 129-35.

As complex treatment techniques such as intensity modulated radiotherapy (IMRT) entail the modeling of rounded leaf-end transmission in the treatment planning system, it is important to accurately determine the dosimetric leaf gap (DLG) value for a precise calculation of dose. The advancements in the application of the electronic portal imaging device (EPID) in quality assurance (QA) and dosimetry have facilitated the determination of DLG in this study. The DLG measurements were performed using both the ionization chamber (DLG_ion) and EPID (DLG_EPID) for sweeping gap fields of different widths. The DLG_ion values were found to be 1.133 mm and 1.120 mm for perpendicular and parallel orientations of the 0.125 cm^{3 ionization chamber, while the corresponding DLG_EPID values were 0.843 mm and 0.819 mm, respectively. It was found that the DLG was independent of volume and orientation of the ionization chamber, depth, source to surface distance (SSD), and the rate of dose delivery. Since the patient-specific QA tests showed comparable results between the IMRT plans based on the DLG_EPID and DLG_ion, it is concluded that the EPID can be a suitable alternative in the determination of DLG.}

6 illus, 4 tables, 29 ref

015108   Shukla P P;Lawrence J (Laser Engineering and Manufacturing Research Group, Faculty of Science and Engineering, Chester Univ, Parkgate Road, Chester CH1 4BJ, United Kingdom, Email: pratik.shukla@talk21.com) : Identification of optical parameters for determination of radiance. J Optics 2015, 44(1), 12-19.

The 'brightness' of coherent beams such as lasers is known as 'radiance' in radiometric terms. It is a concept which is rarely taken into account in laser material processing, laser system design, and for the characterization of laser beams. The typical beam parameters such as: laser power; spot size; intensity; wavelength; beam divergence and the beam propagation factor - M2, combined together are factors which determine the 'radiance' of lasers or energy beams in general. The concept of 'brightness' ('radiance' in particular), and how the laser beam parameters contribute to affect 'radiance', has not so far been reported in previous literature. Thus, we have investigated the theoretical 'radiance' for each parameter in relation to one another. In addition, a rather suitable empirical equation to determine the 'radiance' was also introduced herein, since, the existing equation for calculating 'brightness' do not employ the total power intensity of the beam. Based on this, we consider 'power density' rather than the 'output power' for determining radiance of a selected 1.064 μm wavelength Nd:YAG laser for a set laser processing parameter window. The analytical investigation firstly concluded that the inclusion of 'power density' into the equation takes in account of 'spot size' and 'laser power' to cover all laser beam parameters. Secondly, the results have shown wavelength to be the most contributory parameter to influence the radiance value followed by power density, M2, laser power and lastly the spot size of the laser beam. This was for a set-condition applied, but is generically applicable to different conditions and parameters, whereby, the same tendency would occur. This novel concept of brightness (radiance), of light sources such as a laser beam is not just useful for process control during laser material processing, but could prove to be a very effective concept for laser beam characterization, and in laser system design for enhancing the 'brightness' or 'radiance' of lasers. Also not just lasers but, the concept could be applicable for other energy beams in general.

6 illus, 2 tables, 20 ref

015107   Sheikh S A;Lalmani (Physics Dep, Kasmir Univ, Srinagar-190 006, Email: shabir_222@rediffmail.com) : ELF/VLF radio signals observed at low-latitude station Srinagar, India (L=1.28). Curr Sci 2015, 109(7), 1314-19.

This communication reports dynamic spectra of different ELF/VLF emissions such as hiss, chorus, hisstriggered chorus and whistler-triggered emissions. We also discuss their various observed features. It is argued that most of the emissions are generated during Doppler-shifted cyclotron resonance interaction between the whistler mode wave and energetic electrons. Resonance energy of the participating electron and interaction length are evaluated to explain the generation mechanism of some of these emissions observed at the Indian station Srinagar.

8 illus, 1 table, 59 ref

015106   Sharma G;Bhatt S;Kumar R;Kumar M (Physics Dep, G.B. Pant Univ of Agriculture and Technology, Pantnagar-263 145, Email: munish_dixit@yahoo.com) : Size, shape and temperature effect on nanomaterials. Indian J pure appl Phys 2015, 53(11), 768-75.

Simple theoretical model is developed to study the size, shape and temperature effect on nanomaterials. The temperature dependence of thermal expansion and Young modulus of different type (shape) of nanomaterials viz. spherical, nanowire and nanofilm has been studied. Size dependence of Young modulus in two different regions of temperatures viz. below Debye temperature and above Debye temperature has been investigated for different shape of nanomaterials. The thermal and elastic behaviour is related to vibrational frequency of nanomaterials. Therefore, the size dependence of vibrational frequency of different shape of nanomaterials has been computed. The model predictions are compared with the earlier theoretical and available experimental data. A good agreement supports the validity of the model proposed.

19 illus, 25 ref

015105   Sharma B (Physics Dep, Govt College for Women Parade (Affiliated to Univ of Jammu), Jammu, Email: bandhansharma79@yahoo.com) : Supramolecular structure of phellopterin isolated from the roots of heracleum thomsoni: a furanocoumarin. Indian J pure appl Phys 2015, 53(12), 808-12.

Crystal structure of phellopterin has been determined by X-ray diffraction method. The compound crystallizes in the triclinic space group P1 with unit cell parameters: a = 8.431(3) amstrung, b = 8.947(3) amstrung, c = 11.125(4) amstrung, α = 69.11(5)°, β = 71.13(5)° and γ = 78.04(5) °, Z = 2, V=737.9(4) amstrung^{3. The structure has been solved by direct methods and refined to reliability index of 0.059. The molecules of phellopterin are linked by paired C-H...O hydrogen bond. The face to face π... π stacking interactions link the planar tricyclic moiety with one another and pack in parallel arrangements.}

4 illus, 3 tables, 17 ref

015104   Sharma A;Mahur A K;Ali S A;Sonakawade R G; Sharma A C ("School of Physical Science, B.B.A. Univ of Lucknow, Lucknow) : Monitoring of indoor radon, thoron levels and annual effective dose in some dwelling of Jaipur, Rajasthan, India using double dosimeter cups. Archiv appl Sci Res 2015, 7(2), 1-4.

In present investigation, Solid State Nuclear Track Detectors (SSNTD_s) based twin chamber dosimeter with LR-115 track detector were used for estimating Radon (^{222 Rn) and Thoron (220 Rn) gas concentration levels in the dwellings of Jaipur city. Radon and thoron concentration levels in the studied dwellings were found to vary from 4.6 to 27.4 Bq m-3 and thoron concentrations is found to vary from 3.8 to 22.9 Bq m-3. The annual effective dose due to the exposure to radon and progeny was found to vary from 0.13 to 0.79 mSv whereas from thoron found to vary from 0.09 to 0.57 mSv.}

2 illus, 12 ref

015103   Shafiee S;Akhavan O;Hatami H;Hoseinkhani P (Faculty of Physics, Islamic Azad Univ, PO Box-13185/768, Center Tehran Branch, IR Iran, Email: sshafiee@nri.ac.ir) : Sol-gel synthesis of thermoluminescent Cd-doped ZnTe nanoparticles. Indian J pure appl Phys 2015, 53(12), 804-7.

Cd (3 wt%)-doped ZnTe nanoparticles with average size of 5 nm and band gap energy of 3.15 eV were synthesized by sol-gel method. The optical properties (such as band gap energy) and the size distribution of the nanoparticles have been investigated by using UV-Vis spectroscopy and transmission electron microscopy, respectively. Then, thermoluminescence property of the nanoparticles exposed to various doses of gamma radiation of Cs^{137 has been studied. The thermoluminescence glow peak of the nanoparticles showed a displacement from 290 to 230°C by increasing the dose of gamma radiation from 7.5 to 67.5 mSv. The thermoluminescence intensity of the synthesized Cd-doped ZnTe nanoparticles also showed a linear dose response.}

5 illus, 10 ref

015102   Setrajcic I J;Rodic D;Armakovic S;Setrajcic J P (Physics Dep, Novi Sad Univ, Faculty of Sciences, Trg D. Obradovica 4, 21000 Novi Sad, Vojvodina, Serbia, Email: jovan.setrajcic@df.uns.ac.rs) : Optical properties of layers of symmetric molecular nanofilms. J Optics 2015, 44(1), 1-6.

The changes of optical properties under boundary presence in molecular crystal nanofilm were theoretically investigated in this work. The dispersion law and states of excitons as well as their space distribution along boundary direction have been determined using adjusted Green's function method and also by combined analytical and numerical calculations. We study the basic micro and macroscopic physical characteristics of symmetric ultrathin molecular crystalline films and one can see that essential optical properties of these systems arise with perturbation conditions, which appear at their surface layers. On the basis of real and imaginary part of relative permittivity, the absorption, refraction, reflection and transparency indices were determined, and the influences of boundary parameters on occurrence of a very selective and strictly discrete absorption, refraction and transparency were analyzed. What we have found particularly interesting is the significant percentage of reflected and transparent electromagnetic IR radiation in the nanofilm, although bulk samples of the same crystallographic structure are complete absorbers of this spectrum.

2 illus, 18 ref

015101   Sathish Kumar A;Singh I R R;Sharma D; Ravindran B P (Radiotherapy Dep, Christian Medical College, Vellore, Tamil Nadu, Email: paul@cmcvellore.ac.in) : Performance characteristics of mobile MOSFET dosimeter for kilovoltage X-rays used in guided radiotherapy. J med Phys 2015, 40(3), 123-8.

Main objective of this study was to investigate the characteristics of metal oxide semiconductor field effect transistor (MOSFET) dosimeter for kilovoltage (kV) X-ray beams in order to perform the in vivo dosimetry during image guidance in radiotherapy. The performance characteristics of high sensitivity MOSFET dosimeters were investigated for 80, 90, 100, 110, 120, and 125 kV X-ray beams used for imaging in radiotherapy. This study was performed using Clinac 2100 C/D medical electron linear accelerator with on-board imaging and kV cone beam computed tomography system. The characteristics studied in this work include energy dependence, angular dependence, and linearity. The X-ray beam outputs were measured as per American Association of Physicists in Medicine (AAPM) TG 61 recommendations using PTW parallel plate (PP) ionization chamber, which was calibrated in terms of air kerma (Nk) by the National Standard Laboratory. The MOSFET dosimeters were calibrated against the PP ionization chamber for all the kV X-ray beams and the calibration coefficient was found to be 0.11 cGy/mV with a standard deviation of about ± 1%. The response of MOSFET was found to be energy independent for the kV X-ray energies used in this study. The response of the MOSFET dosimeter was also found independent of angle of incidence for the gantry angles in the range of 0° to 360° in-air as well as at 3 cm depth in tissue equivalent phantom.

7 illus, 2 tables, 14 ref

015100   Santiago J A C;Utrilla M A I;Rodriguez M E L (Medical Physics Dep, Clinica La Luz, Calle General Rodrigo 8, 28003 Madrid, Spain, Email: jcalama@clinicalaluz.es) : Method to improve fluence resolution derived from two-dimensional detector array measurements for patient-specific IMRT verification using the information collected in dynalog files. J med Phys 2015, 40(1), 5-12.

This paper proposes a method for improving the resolution of the fluence derived from detector array measurement using the information collected in dynalog files. From dynalog information, a file is generated with the actual multileaf collimator (MLC) positions and used as input to the treatment planning system (TPS) to obtain the dynalog-derived fluence and the theoretical response over the detector array. In contrast with the measured response, this theoretical response allows for correction of the dynalog-derived fluence and translation into the reconstructed fluence. This fluence is again introduced into the planning system to verify the treatment using clinical tools. Initially, more than 98% of the points passed the two-dimensional (2D) phantom gamma test (3% local dose - 3 mm) for all of the treatment verifications, but in some dose-volume histogram (DVH) comparisons, we note sensitive differences for the planning target volume (PTV) coverage and for the maximum doses in at-risk organs (up to 3.5%). In dose-distribution evaluations, we found differences of up to 5% in the PTV edges in certain cases due to detector array measurement errors. This work improves the resolution of the fluence derived from detector array measurements based on the treatment information, in contrast with the current commercial proposals based on planned data.

6 illus, 26 ref

015099   Saini B;Sharma R;Bamazai R K (Chemistry Dep, Jammu Univ, Jammu-180 006, Email: rkb10@rediffmail.com) : Physico-chemical properties of binary mixtures of tert-butanol with (nitro-, chloro- and bromo-) benzene at 303.15 K and 308.15 K. Indian J pure appl Phys 2015, 53(12), 790-5.

Density (ρ), viscosity (η) and speed of sound (u) of three binary liquid mixtures of tert-butanol with (nitro-, chloro- and bromo-) benzene have been measured over the entire composition range at 303.15 K, 308.15 K and atmospheric pressure. From the experimental data, excess molar volume (V^{E), isentropic compressibility (k_s), excess Gibbs free energy of activation (ΔG*E), deviation parameters like viscosity (Δη), speed of sound (Δu) and isentropic compressibility (Δk_s) are obtained. These functions have been fitted to Redlich-Kister polynomial equation to derive the coefficients and standard deviations.}

5 illus, 2 tables, 21 ref

015098   Saidi S;Trabelsi M;Chefi C;Coulomb J P (Labroatoire de Physics des Materiaux, Faculte des Sciences de Bizerte, 7021 Jarzouna Bizerte, Tunisie, Email: mohsen.trabelsi@fsb.rnu.tn ) : Structural study C₂D₆ thin films adsorbed on MgO (100). Indian J pure appl Phys 2015, 53(11), 748-52.

Structure of C₂D₆ thin films adsorbed on high homogeneous MgO (100) powder surface have been investigated by means of neutron diffraction techniques at 10 K. Neutron diffraction spectra have been recorded for three different coverages. Two bi-dimensional solids S₁ and S₂ have been determined, respectively for a coverage θ =0.7 layer and θ =1.2 layer. In agreement with LEED measurement, the S₂ phase presents the commensurability C(2x2)R45° with the MgO (100) surface. The S₁ phase also presents a commensurate structure with the substrate lattice but its commensurability is weaker than that of S₂. The (2D) solid phase, measured at an intermediate coverage θ =1.0 layer is a mixture of S₁ and S₂. For both solid phases, unit cell, location and orientation of molecules within are determined. The commensurate cell of the S₁ solid with the MgO (100) surface is given.

3 illus, 1 table, 12 ref

015097   Sahoo S;Middya T R;Sit S K (Electronics & Instrumentation Engineering Dep, Jadavpur Univ, Kolkata, West Bengal, Email: swapansit@yahoo.co.in) : Relaxation phenomena of acrylic esters and phenols in dilute solution of CCl₄ under static and high frequency electric field. Indian J pure appl Phys 2015, 53(11), 725-35.

Double relaxation times τ₂ and τ₁ due to whole molecular rotation and the flexible parts of the binary (jk) polar mixture of p-cresol, p-chlorophenol, 2,4 dichlorophenol and p-bromophenol with methyl methacrylate (MMA) or ethyl methacrylate (EMA) were estimated under 9.37 GH_Z electric field dissolved in dilute CCl₄ solution at 35°C using high frequency susceptibility data χ_ijk's for different weight fractions w_jk's. Six systems out of eight exhibit τ₂, τ₁; τc₂, c₁ and μ₂, μ1, respectively. The estimated τ₂'s and μ₂'s agree well with the measured and reported values indicating the whole rotation of binary polar mixture under high frequency electric field. Solute-solute and solute-solvent molecular formation through H-bonding are ascertained from μ_av - x_j curves for 0.5 mole fraction x_j of acrylic ester. The associational aspects are taken into consideration in μ_theo from the stand point of inductive, mesomeric and electromeric effects within the polar groups of the molecules. Static μ₀'s are calculated and compared with the reported values also.

9 illus, 3 tables, 20 ref

015096   Ramesh Chand;Rana G C (Mathematics Dep, Government College, Nurpur, Himachal Pradesh) : Instability of Walter's B' visco-elastic nanofluid layer heated from below. Indian J pure appl Phys 2015, 53(11), 759-67.

Thermal instability in a horizontal layer of Walter's B' visco-elastic nanofluid has been investigated. A linear stability analysis based upon normal mode technique and perturbation method is used to find the solution of the fluid layer confined between two free-free boundaries. The stability criteria for stationary and oscillatory convection have been derived and graphs have been plotted to study the effects of the concentration Rayleigh number, Prandtl number, capacity ratio, Lewis number and kinematics visco elasticity parameter on the stationary and oscillatory convection. The sufficient conditions for the non-existence of oscillatory convection have also been obtained.

8 illus, 34 ref

015095   Philominal A;Thenmozhi M;Ponnuswamy M N; Dhanuskodi S (School of Physics, Bharathidasan Univ, Tiruchirappalli) : Spectral, optical, thermal and mechanical studies of metakl halide co-ordinate pyridinium derivatives. Archiv appl Sci Res 2015, 7(2), 39-49.

Metal - organic coordination compounds dichloridobis(l-ethyl-2, 6-dimethylpyridinium-4-olate-KO) zinc (II) (EDMPZC) and dibromidobis(l-ethyl-2, 6-dimethylpyridinium-4-olate-KO) zinc (II) (EDMPZB) was designed and synthesized and single crystals was grown by solvent evaporation technique. Both the complexes were characterized by single crystal X-ray diffractometry, FTIR, FT NMR and elemental analyses. Optical transmittance window and the lower cutoff wavelength (262 nm for EDMPZC and 263 nm for EDMPZB) were identified from the linear optical studies. Laser induced surface damage threshold of EDMPZC and EDMPZB are 29.25 GW/cm^{2 and 71.16 GW/cm2 respectively. Thermal stability of the complexes was performed by Thermogravimetric. Differential Thermal Analysis (TG/DTA), and Differential Scanning Calorimetry (DSC) techniques.}

5 illus, 6 tables, 23 ref