011912   Vandana Arya;Singh D V (Physics Dep, Agra College, Agra-282 002, Email: phdphy06@rediff.com) : Opto-electronic properties of binary tetrahedral semiconductors. Ultra Scient phys Sci-Sect B 2011, 23(1), 215-19.

The Phillips and Van Vechten theory was applied to binary compounds (ZnS, ZnSe, ZnTe & Cds, CdSe, CdTe,). Electronic polarizability was investigated using the Chemla relation and values were found to be in good agreement with the results obtained from the Clausius Mossotti relation. The dependence of refractive index for binary compounds on the energy gap and plasmon energy from the Penn model. The optical dielectric constant (ε_∞) has also been investigated. The values of these parameters thus obtained are in good agreement with previously reported experimental data and theoretical findings.

2 tables, 30 ref

011911   Vandana Arya;Chauhan A;Singh D V (Physics Dep, Agra College, Agra, U.P.) : Analysis of electronic properties of alkali mono halide crystals. Ultra Scient phys Sci-Sect B 2011, 23(1), 1-6.

The electronic, optical, electrical and transport properties of alkali halide crystals have been discussed. The various physical parameters such as ionicity, polarizability, bulk modulus, plasmon energy have been computed and compared with the reported data. A discussion based on PVV theory has been presented for the derived hompolar gap (Eh), Ionic gap (E_c), Perm gap (E_p), average gap (E_g), correlating ionicity with E_c & Eg as well as with various hyperfine interaction. The polarizability is investigated using the Cheml's relation and the investigated values are shown to be in accordance with the values from Clausius-Mossotti relation. The Phillips ionicity is evaluated and is used to determine the bulk modulus of these materials. The Philips ionicity is calculated and compared with the ionicity of the Tubbs and Pauling, models. The plasmon energy is evaluated using the static and optical dielectric, constant using Phillips and perm models.

4 tables, 24 ref

011910   Tumberphale U B;Kalamse V G;Narwade B S; Kalamse G M (Microwave Research Laboratory, Physics Dep, Science College, Nanded-431 605, Email: kalamse_gm123@rediffmail.com) : Dielectric relaxation studies of binary mixtures of aniline + 2-methoxyethanol in benzene from microwave absorption data. Bionano Front 2013, 6(1), 144-8.

Die1ectric relaxation time (τ) and dipole moment (μ) for dilute solutions of binary mixtures of Aniline + 2-Methoxy ethanol in Benzene are obtained at 9.85 GHz microwave frequency. Energy parameters (ΔH, ΔF, ΔS ) for dielectric relaxation process of Aniline + 2-Methoxy ethanol mixtures containing (0, 22, 46, 72 and 100%) aniline have also been calculated. Compairsion has been made with corresponding energy parameters for viscous flow. Debye's factor (C), Kalman's factor (C') and inverse relaxation time were computed. The variation of relaxation time and inverse relaxation time with mole fraction of Aniline in the mixture confirms solute solute and solute solvent interactions.

2 illus, 4 tables, 18 ref

011909   Thakur A N;Singh S N;Ajay Kumar;Ahmad A (Phtysics Dep, T.D.P.G. College, Jaunpur-222 002, Email: ant_tdc@yahoo.com ) : Dielectric and electrical transport properties of terbium orthochromites. Ultra Scient phys Sci-Sect B 2011, 23(3), 717-23.

Reports the measurement of dielectric (K), electrical Conductivity (σ) and Seebeck coefficient (S) of terbium orthochromite in the temperature range of 350 to 1000K. TbCrO₃ is a large dielectric constant material with K values of 316 at 10² Hz and 100 at 10³ Hz at 350K. The logK vs T plot is not smooth but shows anamolies at 446K and 755 K, the latter has been interpreted as a phase transition of the material. Above 1000 K the value of dielectric constant starts decreasing with temperature which is a typical characteristic of ferroelectric materials. The log σT vs T^-1 as well as S vs T^-1 plots show four distinct linear regions in the temperature intervals of 384- 444K, 444-714K, 800-1000 K and 1000-1100 K. The S values are positive and constant in these temperature intervals but log σT vs T^-1 plot has slopes of 0.34 eV, 0.48 eV, 0.73 eV and 0.73 eV in the four temperature ranges. It has been concluded that intrinsic band conduction is not the mechanism of electrical conductivity but it occurs due to hopping of electrons from Cr³⁺ to Cr⁴⁺ centres. These Cr⁴⁺ centres are created due to native defects. The number of these centres as well as the resulting Seebeck coefficient have also been calculated. The latter has a good agreement with the experimentally observed values.

4 tables, 21 ref

011908   Srivastava S;Pandey B;Tiwari S;Shukla S (Physics and Electronics Dep, Dr.R.M.L. Avadh Univ, Faizabad-224 001, Email: sachida_shukla@yahoo.co.in) : Qualitative analysis of MOS based complementary-symmetry class_B push-pull amplifier with improved efficiency. Ultra Scient phys Sci-Sect B 2011, 23(3), 703-8.

Modified MOSFET based circuit of Complementary-Symmetry Class-B Push-Pull Amplifier' is proposed. The proposed amplifier circuit produces improved power amplification efficiency (PAE) to 65.2% and reduced harmonic distortion to 1.10%. Variation of maximum voltage gain as a function of biasing resistances is also observed.

5 illus, 7 ref

011907   Srivastava A K (Physics Dep, D.A.V. P.G. College, Kanpur, Uttar Pradesh, Email: am97@rediffmail.com) : Plane symmetric perfect fluid distributions with heat flux. Ultra Scient phys Sci-Sect B 2011, 23(2), 359-64.

Presented that perfect fluid with heat flux distributions, in plane symmetry admitting a one parameter group of conformal motions are not admitted. Hence, Authors have investigated exact plane symmetric perfect fluid solutions of Einstein equations assuming one parameter group of conformal motions. Geometrical and physical properties of some particular solutions so obtained, are presented.

12 ref

011906   Siva Ramaiah G (Physics Dep, Government College for Men, Kadapa-516 004, Email: gsivaram7@yahoo.co.in) : Calculation of thermodynamic potentials of Fe<. Proc Indian Natn Sci Acad 2011, 77(3), 241-8.

From electron paramagnetic resonance data of Fe³⁺ and Mn²⁺ ions in alkali lead tetraborate glasses, the thermodynamic potentials such as Gibbs potential ΔG, entropy of activation AS, enthalpy of activation AH have been evaluated. The effect of temperature, concentration and alkali ions on Gibbs potential is studied for Fe³⁺ and Mn²⁺ ions in alkali lead tetraborate glasses. It is observed that the Gibbs potential has increased with the increase of concentration and temperature. The Pauli magnetic susceptibility is calculated at 296 K and different temperatures (123-393 K) for Fe³⁺ and Mn²⁺ ions in alkali lead tetraborate glasses. The pre-exponetial coefficient is calculated from the logarithmic of number of spins and the reciprocal of absolute temperature graph of Fe³⁺ and Mn²⁺ ions in alkali lead tetraborate glasses. The pre-exponential coefficient indicates the collision frequency between the transition metal ion and the glass host lattice. The phase memory relaxation time T_m (T₂) and the spin-lattice relaxation time T₁ were calculated for the two ions. The temperature effect of the relaxation times was studied for the two ions. The Gibbs potential, pre-exponential coefficient, Pauli magnetic susceptibility, relaxation times were compared among Fe³⁺ and Mn²⁺ ions in alkali lead tetraborate glasses. These values were compared among alkali ions in alkali lead tetraborate glasses.

3 illus, 2 tables, 19 ref

011905   Singh S N;Singh A;Thakur A N (Physics Dep, T.D.P.G. College, Jaunpur-222 002, Email: snstdcjnp@gmail.com) : Self-similar radiating flows in Roche-model with an idealized magnetic field. Ultra Scient phys Sci-Sect B 2011, 23(3), 683-90.

The present theory is applied to describe shock waves in a gravitational field due to a heavy nucleus at the origin including the effects of radiative flux and an idealized azimuthal magnetic field, when the total energy of the disturbance is of increasing order. Singh have considered a self-similar class of spherical gas dynamic disturbances in a gravitational field using the concept of Generalized Roche model into an in homogeneous ideal gas. Authors gave the results of the study for two different models; constant total energy of explosion and varying total energy of explosion with and without magnetic field are shown through the figure.

9 illus, 54 ref

011904   Singh J P;Tribhuwan Kumar;Dubey R P (Physics Dep, R.P.G. College Jamuhai, Jaunpur, U.P.) : On microscopic picture for the black hole. Ultra Scient phys Sci-Sect B 2011, 23(3), 531-4.

Evaluations in general theory of relativity have provided an interesting phase picture for the black hole- black string phase transition. We are interested to present microscopic picture for the black hole of (4+1) dimensional near-extremal holes and (3+1) dimensional near-extremal holes for the compactification radius is very large or very small respectively.

21 ref

011903   Singh J P;Pandey A K (Physics Dep, R.P.G. College Jamuhai, Jaunpur, U.P.) : Entropy of horizons. Ultra Scient phys Sci-Sect B 2011, 23(1), 162-8.

Presented the analytic properties of spacetime manifold in the complex plane directly lead to the association of a temperature with a generic class of horizons with a generic class of horizons.

31 ref

011902   Singh A K (Physics Dep, Bareilly College, Bareilly-243 005, Email: aksnmr@gmail.com) : <. Ultra Scient phys Sci-Sect B 2011, 23(2), 249-54.

The experimental values of NMR spin lattice relaxation time (T₁) of 2-aminopyridine, 3-Aminopyridine, 4-Aminopyridine, 2-Chloropyridine and 3-Bromopyridine have been reported. These values of T1 have been correlated with the calculated values of TI obtained using various equations for dielectric relaxation time (τ). This comparative study concludes that the values of dielectric relaxation time and NMR spin lattice relaxation time obtained using Murty equation are in better agreement with the experimental values. Experimental values of the mutual viscosity (η₁₂) of 2-aminopyridine, 3-Aminopyridine and 4-Aminopyridine have been also reported. It has been concluded that the mutual viscosity is a better substitute for the resistance to the rotation of the individual solute molecule.

3 tables, 14 ref

011901   Shukla L J;Rajendra Prasad;Dubey R P (Physics Dep, R.H.S.P.G. College, Singramau, Jaunpur, Uttar Pradesh) : On black hole- black string phase transition. Ultra Scient phys Sci-Sect B 2011, 23(3), 621-5.

Presented another property of black holes that may be obtained in classical general relativity: the transition between black holes and black strings when a transverse circle is made large or small. We have suggested a simple microscopic picture of this transition.

7 ref

011900   Shinde A B;Kurmude D V;Kale C M;More S D; Jadhav K M (NO, Abasaheb Garware College, Pune) : Synthesis and physical properties of cobalt ferrite nanoparticles. Bionano Front 2013, 6(1), 6-8.

Cobalt ferrite (CoFe₂O₄) nanoparticles were synthesized by sol gel auto combustion technique using respective metal nitrates and using citric acid as fuel for combustion process. The formation of ferrite nanoparticles with single phase spinel structure is evident from X-ray diffraction analysis. Broad XRD peaks indicate the formation of nanoparticles. Average particle size calculated from most intense reflection (311) using Debye-Scherrer's formula is found to be 24 nm. The lattice constant and other structural parameters evaluated from XRD data are in reported range. EDAX data confirms that the reactants have undergone complete reaction. In the present case the cation distribution estimated X-ray intensity ratio analysis confirms the inverse spinel structure of cobalt ferrite. Observed and theoretical lattice parameter is found to be in agreement with each other. Magnetization study of the prepared samples is carried out using pulse field hysteresis loop technique. Magnetic parameters obtained are slightly enhanced may be due to nano crystalline nature of prepared cobalt ferrite. In summery the physical properties of cobalt ferrite nanoparticles are influenced by synthesis method.

3 illus, 1 table, 17 ref

011899   Sheena Maryy;Varghese H T;Yohannan Panicker C;Abdul Salim M (Physics Dep, Fatima Mata National College, Kollam, Kerala) : Spectroscopic investigations of cyclopropanecarboxylic acid. Ultra Scient phys Sci-Sect B 2011, 23(3), 616-20.

The infrared spectrum and Raman spectrum of cyclopropa-necarboxylic acid were recorded and analysed. Geometry and harmonic vibrational frequencies were calculated theoretically using Gaussian03 set of quantum chemistry codes. Calculations were performed at the Hartree-Fock and DFT level of theory using the standard 6-31G* basis. The calculated wavenumbers(B3LYP) agree well with the observed wavenumbers. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands found in the IR and Raman spectra of the studied molecule. Calculated infrared intensities, Raman activities and first hyperpolarizability are reported. The calculated first hyperpolarizability is high and the title compound may be an attractive object for further studies on non linear optics.

1 table, 18 ref

011898   Sheena Mary Y;Yohannan Panicker C;Varghese H T;Mary Genia T G;Anto P L (Physics Dep, Fatima Mata National College, Kollam-1, Kerala, Email: cyphyp@rediffmail.com) : IR, Raman and computational study of m-nitroanisole. Ultra Scient phys Sci-Sect B 2011, 23(3), 501-6.

The infrared and Raman spectra of m-nitroanisole have been recorded and analyzed. The vibrational wavenumbers were calculated theoretically using Gaussian03 set of quantum chemistry codes. The data obtained from vibrational wavenumber calculation are used to assign vibrational bands found in the infrared and Raman spectra of the studied molecule.

20 ref

011897   Sheena Mary Y;Varghese H T;Yohannan Panicker C;Mary Genia T G;Anto P L (Physics Dep, Fatima Mata National College, Kollam-1, Kerala) : Spectroscopic investigations of 3-cyclohexene-1-carboxylic acid. Ultra Scient phys Sci-Sect B 2011, 23(3), 525-30.

The IR and Raman spectra of 3-cyclohexene-l-carboxylic acid have been recorded and analyzed. Geometry and harmonic vibrational wavenumbers were calculated theoretically using Gaussian03 software package. Calculations were performed at the Hartree-Fock and DFT levels of theory using the standard 6-31G* basis. The calculated wavenumbers (B3LYP) agree well with the observed wavenumbers. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands found in the IR and Raman spectra of the studied molecule. The calculated first hyperpolarizability is very high and the studied molecule may be an attractive object for further studies on non linear optics. The predicted infrared intensities and Raman activities are reported.

1 table, 23 ref

011896   Sharma K K;Verma K R;Saxena S (Physics Dep, IIET, Invertis Univ, Bareilly-243 123) : Positron (electron) impact excitation of inert gas atom. Ultra Scient phys Sci-Sect B 2011, 23(3), 677-82.

Computed excitation cross section (ECS) of inert gas atom (Krypton) by impact of positron and electron using close coupling approximation method. High quality Hartree-Fock Slater orbitals are used to model the target wave function. We have already computed the excitation results for inert gas atoms (Ne, Ar, Kr, and Xe) by positron as well as electron impact, but in this paper, we are presenting for Krypton atom only. Full orthogonalization significantly improves agreement with experimental data for the noble gas series. Compared ECS results with other available theoretical results as well as experimental data. The present results are found in excellent agreement with other calculations. However some discrepancies suggested that more theoretical as well as experimental work is required in future to improve the data.

2 illus, 16 ref

011895   Sampath Krishnan S;Santhana Krishnan V; Kumutha R (Applied Physics Dep, Sri Venkateswara College of Engineering, Sriperumbudur-602 105, Email: sambathk@svce.ac.in) : Ab initio, density functional theory and structural studies of pemoline. Ultra Scient phys Sci-Sect B 2011, 23(2), 475-81.

Quantum mechanical calculation of energies, geometries and vibrational analysis of pemoline (2-Amino 5-Phenyl 2-Oxazoline 4-one) were carried out by using ab initio HF and Density functional theory (DFT/B3LYP) methods with 6.31 G (d,p) basis set. The optimized geometry parameters obtained by HF and DFT calculations are in very good agreement. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) are stimulated. The thermodynamic functions of the title molecule were also performed using HF and DFT methods.

1 illus, 3 tables, 5 ref

011894   Sampath Krishnan S;Santhana Krishnan V; Kumutha R (Applied Physics Dep, Sri Venkateswara College of Engineering, Sriperumbudur-602 105, Email: sambathk@svce.ac.in) : Molecular structure vibrational spectroscopic studies and analysis of diazzopropyne. Ultra Scient phys Sci-Sect B 2011, 23(1), 169-75.

Quantum mechanical calculation of energies, geometries and vibrational wave numbers of diazopropyne have been carried out by using density functional theory (DFT/B3LYP) method with 6.311++G (d,p) cc-pvdz, Aug-cc-pvdz as basis set. The optimized geometrical parameters obtained by DFT calculations are found to be good agreement with experimental X-ray data. The best level of theory in order to reproduce the experimental wave numbers is B3LYP method with the 6.311 ++G(d,p) basis set. The difference between the observed and scaled wave number values of most of the fundamentals is very small. A detail interpretation of the infrared and Raman spectra has also been reported. The entropy of the compound under study is also performed. Application of Redington's method in the solution of eleventh and fourth order problems involved in vibrational analysis of diazopropyne (C₃H₂N₂) molecules. General quadratic valence force field has been used to calculate the force constants and mean amplitudes of vibration are also calculated in the present work. The results are discussed.

3 illus, 6 tables, 4 ref

011893   Sahoo N B;Pattnaik B K;Biswal S (Physics Dep, P.N. Autonomous College, Khurda) : Heat and mass transfer in the oscillatory hydromagnetic free convective flow of a visco-elastic fluid past an infinite vertical porous plate with constant suction and heat dissipation. Ultra Scient phys Sci-Sect B 2011, 23(1), 103-22.

Heat and mass transfer in the oscillatory hydromagnetic free convective flow of a visco-elastic fluid past an infinite vertical porous plate with constant suction and heat dissipation has been studied. Constitutive equations of the problem have been developed and solutions are arrived at following small parameter perturbation technique. The effects of various fluid parameters like non-Newtonian parameter RC, Grashof number G, modified Grashof number G_c, Eckert number E and magnetic parameter M on the mean and transient velocity field have been studied with the help of graphs. Similarly, the effects of Prandtl number P alongwith the other parameters have been exhibited through graphs. The effect of Schmidt number S_c on the mean concentration has been shown by the graph. The values of skin-frictions, rates of heat transfer and concentration gradient have been entered in the tables with the variations of the fluid parameters. It is observed that the magnetic field decelerates the flow of the visco-elastic fluid under consideration.

5 illus, 7 tables, 11 ref

011892   Rawat D;Gaur N K (Physics Dep, Saifia P.G. College of Science and Education, Bhopal-462 001) : Evaluation of elastic constant and pressure derivatives of mixed deuterium halides. Ultra Scient phys Sci-Sect B 2011, 23(2), 305-12.

Authors have investigated the elastic constant and Pressure Derivatives of mixed Deuterium Halides and are evaluated by using three-body interaction potential model which can predict Third order elastic constant (TOEC), Fourth order elastic constant (FOEC) and Pressure Derivatives of Second order elastic constant (SOEC) and Third order elastic constant (TOEC). Theoretical results are in good agreement with experimental data. Most of the physical properties like high pressure phase transition, cohesive energy and other properties of some ionic and partially covalent crystals are also obtained.

5 tables, 20 ref

011891   Priyanka Rani;Thakur A N;Raghuvanshi P (Physics Dep, Tilak Dhari Post Graduate College, Jaunpur-222 002, Email: ant_tdc@yahoo.com) : Synthesis, characterization and dielectric properties of Re₂Zr₂O₇ (Re = Y & Gd). Ultra Scient phys Sci-Sect B 2011, 23(2), 285-92.

The polycrystal line rare-earth metal zirconates Re₂Zr₂O₇, where Re = Y and Gd have been synthesized by the solid state reaction technique. The synthesis process was monitored by differential thermal analysis (DTA), thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG). The compounds were characterized through powder XRD. XRD patterns show them to be single phase orthorhombic structure at room temperature. The dielectric constant (ε) and dielectric loss (ε") of the compounds have been measured at 1kHz in the temperature range 300 to 1125K. The log ε vs Tand log ε" vs T plots of Y₂Zr₂O₇ and Gd₂Zr₂O₇ show rapid increase of dielectric constant and dielectric loss above 700K and 680K respectively.

6 illus, 3 tables, 18 ref

011890   Priyanka Rani;Thakur A N;Raghuvanshi P (Physics Dep, T.D. Post Graduate College, Jaunpur-222 002, Email: ant_tdc@yahoo.com) : Investigation of structural and electrical properties of heavy rare-earth zirconate compounds. Ultra Scient phys Sci-Sect B 2011, 23(2), 267-74.

Heavy rare-earth zirconate R₂Zr₂O₇ compound (where R = Y & Gd) was prepared by solid state reaction at 1300K for 50h. The prepared compound has been characterized by X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG). The XRD Studies indicates the formation of single phase orthorhombic structure at room temperature. The electrical conductivity of R₂Zr₂O₇ compound were measured in the temperature range 300-1125 K at an internal frequency of 1 kHz. The logσvs. 10³/T plot yield the different slopes separated by break temperature (T₁). The activation energy below and above this break temperature have been estimated as approximately 0.10eV and 3eV respectively. Hence the electrical conduction below T₁ is essentially extrinsic always associated with impurities, defects and interstitials and conduction above T₁ is essentially intrinsic due to the change in conduction mechanism.

6 illus, 3 tables, 13 ref

011889   Pradhan S K;Dash S K;Swain M D;Swain B B (Physics Dep, Nayagarh Autonomous College, Nayagarh-752 069, Email: bb.swain@vivtech.co.in) : Ultrasonic study of moleculat interaction parameters in binary mixtures of diethyl ether (DEE) and some apolar solvents. Ultra Scient phys Sci-Sect B 2011, 23(2), 387-96.

Viscosities (η), densities (p) and ultrasonic velocities (U) were measured at 303.16K for binary mixtures of diethyl ether with carbon tetrachloride, carbon disulphide and benzene. Using these measured values, isentropic compressibility (β_s), intermolecular free length (L_f), molar volume (F_m), acoustic impedance (Z), available volume (V_a), free volume (V_f), internal pressure (π_i) and the relaxation time (λ) were calculated. The behaviour of these parameters with molefraction of the mixtures has been discussed in terms of molecular interactions between the components of liquids. The larger negative deviation in the values of β^E_S,L^E_f, V^E_f indicates that dipole-induced dipole type of interaction was found to be stronger in case of CCl₄ mixture.

8 illus, 1 table, 32 ref

011888   Pensia R K;Patidar A K;Vishal Kumar;Prajapat V (Physics Post Graduate Dep, Govt. P.G. College, Neemach, M.P., Email: rkpensia@rediffmail.com) : Role of heat-loss function on the growth of molecular clouds in our galaxy. Ultra Scient phys Sci-Sect B 2011, 23(1), 43-8.

The role of heat-loss function on the growth of molecular clouds in infinite homogenous thermally conducting viscous plasma incorporating permeability in the presence of suspended particles has been investigated. A general dispersion relation is obtained by using the normal mode analysis with the help of relevant linearized perturbation equations of the problem and a modified Jeans criterion of instability is obtained.

13 ref

011887   Pandey A N;Maurya K K;Dubey R P (Physics Dep, K.N. Govt. P.G. College, Gyanpur, S.R.N. Bhadohi, Uttar Pradesh) : Spherical and non-spherical gravitational collapse in anti-de-Sitter-Husain spacetime. Ultra Scient phys Sci-Sect B 2011, 23(3), 551-6.

Investigated the spacetime singularities in the gravitational collapse of anti-de-Sitter-Husain spacetime. Obtained that spherically symmetric anti-de-Sitter-Husain spacetime contradicts the cosmic censorship conjecture (ccc) whereas non-spherical collapse respects it.

17 ref

011886   Pal J (Physics Dep, Dr B.C. Roy Engineering College, Fuljhor, Durgapur, West Bengal, Email: jayantabappa5@yahoo.co.in ) : Specific contact resistance of Cu_xO thin films deposited by r.f. sputtering method. J Alternate Energy Sour Technol 2012, 3(3), 10-16.

This paper contains measurement of contact resistivity and bulk resistivity of Cu_xO (0<60>x<60>l) thin films deposited by r. f. sputtering method. The conditions for deposition of Cu_xO thin film were optimized by varying the r. f. power to vary the contact resistivity and bulk resistivity. Electrical characterizations were performed by Transmission Line Model (TLM) and Vertical Transmission Model (VTM) studies. The films deposited on glass substrate have contact resistivity in the range 2.53 - 15 Ω-cm² and bulk resistivity in the range 0.35 - 0.96 Ω-cm.

6 illus, 3 tables, 15 ref

011885   Mishra A;Ray G S;Biswal S (Physics Dep, A.D. Mahavidyalaya, Brahmagiri, Puri, Email: dr.sadasivabiswal@ymail.com) : Heat transfer in the rotational flow of a visco-elastic liquid due to rotation of an infinite porous disk in the presence of heat sources. Ultra Scient phys Sci-Sect B 2011, 23(3), 515-24.

This paper deals with the study of heat transfer in the rotational flow of a visco-elastic liquid due to rotation of an infinite porous disk in the presence of heat sources. Constitutive equations of the problem have been developed in order to formulate the problem under the prescribed boundary conditions. Runge-kutta technique of numerical integration has been used to solve the non-linear equations of motion and energy. Velocity and temperature profiles have been shown by graphs whereas the values of skin-friction and rate of heat transfer have been entered in tables. It is observed that drag on the disk in larger in case of non-Newtonian fluid than Newtonian fluid. Increase in the permeability parameter increases the rate of rotational flow of the visco-elastic fluid. The Reynolds number (R₁) raises the temperature at any point of the fluid.

3 illus, 3 tables, 23 ref

011884   Mishra A K (NO, , Gandhi Nagar (Piper Deura) Post & Distt. Maharajganj-273 303) : N-dimensional spherical spacetimes. Ultra Scient phys Sci-Sect B 2011, 23(1), 220-6.

Large class of N-dimensional spherical spacetimes is found, which includes most of the known solutions. A family of the generalising collapsing Vaidya solutions with homothetic self-similarity, parametrized by a constant λ, is studied, and found that when λ, <62> λ_c(N), the collapse always forms black holes, and when λ <60>λ_c (N), it always forms naked singularities, where λ,c (N) is function of the spacetime dimension N only.

17 ref

011883   Mahipal Singh (Physics Dep, Govt. P.G. College, Bageshwar-263 642, Email: dmpsc@rediffmail.com) : Influence of temperature on penetration depth in bilayer cuprate superconductors. Ultra Scient phys Sci-Sect B 2011, 23(1), 27-36.

The present work deals with the study of penetration depth as a function of temperature and various other microscopic interactions that exit in bilayer high temperature cuprate superconducting materials. For this, we consider a tight binding bilayer Hubbard Hamiltonian that includes the in-plane(within CuO₂ plane) and out-of-plane interactions and employ Green's function technique to describe various correlations, important in superconductivity phase. The expressions for superconducting order parameters, carrier density and penetration depth are obtained. The numerical analysis shows that in bilayer cuprates the penetration depth depends on various in-plane and out-of-plane contributions as well as on temperature in an essential way. Finally, we have compared our theoretical results on penetration depth with that of recent experimental findings and found to be in qualitative agreement.

2 illus, 31 ref

011882   Krishnakutty K;Krishnakumar G;Mohanan S (Physics Dep, College Univ, Thiruvananthapuram, Kerala) : Thermo opto acoustic analysis to detect photochemical reaction of medicine methadilazine. Ultra Scient phys Sci-Sect B 2011, 23(2), 369-76.

Thermo-optoacoustic analysis has been used to detect the photo chemical reactions in medicine methadilazine,used as phenothiazine compound with anti histamine activity. Certain derived optoacoustic parameters of pure medicine and that exposed to solar radiations have been determined as a function of temperature. Plots of these parameters versus temperature have been made. The nature of variation and the relative shift in the curves for the exposed samples compared with the un exposed ones have been used to study photo chemical reactions. The results have been explained in the light of existing theories and confirmed using UV absorption spectra of the samples.

6 illus, 1 table, 16 ref

011881   Kimothi S;Nainwal S;Thapliyal A (NO, Uttarakhand Graphic Era Hill Univ, 600, Bell Road Clement Town, Dehradun, Uttarakhand, Email: sanjeevkimothi@gmail.com) : Retrieval of incoming shortwave radiation using staellite approaches. J Remote Sensing GIS 2012, 3(2), 46-59.

Aim of this paper is to review the detail of incoming shortwave radiation retrieval approaches and put forth the required inputs. This review covers the worldwide research study for the estimation of incoming radiation using geostationary platform. Researches on the estimation of ground solar radiation have concentrated mom on using the data from geostationary meteorological satellites since the orbit gives an advantage of obtaining multiple acquisitions in a day to account for diurnal and cloud-related variability. It was emphasized by several authors that accuracy may decrease if stations used for interpolation are located in two different climatic areas suck as desert, coastal or if they are separated by physiographic structures such as mountainous, rucky area, etc. The attenuation coefficient of cloud could be computed by using Mie theory of scattering. A physical retrieval scheme of mapping irradiation by Meteosat-5 VISSR sensor data over the Indian landmass for the different climatic conditions shows the satellite sensor capability to capture seasonal irradiation.

2 illus, 48 ref

011880   Khandayat S K;Dhurve G;Shrivastava P K (Physics Dep, Govt. College, Nainpur, District Mandala, Madhya Pradesh) : Solar wind variability and geomagnetic activity. Ultra Scient phys Sci-Sect B 2011, 23(2), 494-500.

Solar wind is a dominant feature in interplanetary space at 1 AU. Events of high speed solar wind streams (HSSWS) have been taken to derive their relationship with geomagnetic activity for the period of 1996 to 2007; covering the solar cycle 23. Results of the analysis indicate that HSSW streams produce larger geomagnetic field variation during the decreasing phase of solar cycle 23. Minimum solar activity years show smaller increase in Ap values.

5 illus, 8 ref

011879   Jothe M;Mahendra Singh;Shrivastava P K (Physics Dep, Govt. M.G.M. PG.College, Itarsi-461 111, Email: jothemkj@gamil.com) : Magnetic clouds and associated cosmic ray intensity variations. Ultra Scient phys Sci-Sect B 2011, 23(3), 511-14.

Detailed analysis has been carried out to the effects of magnetic cloud events with and without association of interplanetary shocks. Ninety-six magnetic clouds are identified during the period from 1996 to 2007 using the superposed epoch analysis. The solar wind velocity and interplanetary magnetic field enhanced ahead of magnetic cloud that are preceded by a shock. A large decrease in cosmic ray intensity is noticed during the passes of interplanetary shock associated magnetic clouds.

1 illus, 7 ref

011878   Intekhab Amin S;Alam M S (Electronics & Communication Engineering Dep, Z.H.C.E.T. Aligarh Muslim Univ, Aligarh-202 002, Email: intekhabamin@gmail.com) : Virtual farbrication and analog performance of sub-40n m bulk mosfet using TACD tool. J Elect Des Technol 2010, 1(1), 1-6.

Virtual Fabrication of sub-40nm Bulk MOSFET is carried out under channel engineering and source drain engineering process. These structures enable more aggressive device scaling in nano-scale region because of their ability to control short channel effects. How ever during scaling the junction depth should also be scaled down, which increases parasitic resistance so silicidation technique has been applied to reduce their effects on device. Analog performance has been measured in terms of gm, gds, Av, f_T and f_max. The simulation result predict that gm is 3.75ms for engineered MOSFET as compared to non-engineered MOSFET with gm of 2.9ms for similar gate length, similarly A_v for engineered device is 17.5 db and for non-engineered device is 6.96 db, f_T is 146GHz and for non-engineered f_T is 65GHz, f_max is 299GHz for engineered device and for non-engineered device f_max is 170GHz and a comparison of an engineered device is done with a non engineered device to investigate the improved performance of an engineered device as compared to a non engineered device. Silvaco TCAD Tool is used for Virtual fabrication and simulation. ATHENA process simulator is used for virtual fabrication and ATLAS device simulator is used for device characterization.

11 illus, 1 table, 9 ref

011877   Goswami M;Jena M;Biswal S (NO, Regional Institute of Education, Bhubaneswar) : Momentum and heat transfer in the MHD unsteady flow of a visco-elastic liquid over an oscillating porous plate in a rotating frame with varied species concentration and dissipation. Ultra Scient phys Sci-Sect B 2011, 23(2), 255-66.

Heat and mass transfer in the magnetohydrodynamic flow of a visco-elastic fluid over an oscillating porous plate in a rotating frame with dissipation has been studied. After solving the constitutive equations of motion, energy and concentration by the use of complex functions, results have been discussed with the help of graphs and tables. It is observed that the velocity of flow increases with the non-Newtonian parameter (R_c) whereas the transverse component of the velocity of flow decreases with R_c. Magnetic parameter decelerates the flow.

9 illus, 5 tables, 8 ref

011876   Ghatak B (Univ Physics Dep, T.M.B. Univ, Bhagalpur-812 007, Bihar, Email: biswajit.ghatak@rediffmail.com) : Theoretical evaluation some properties (Gruneisen parameter, second Gruneisen parameter, Anderson Gruneisen parameter) of alkali chalcogenide crystals (oxides and sulphides) using two interaction potential energy functions (IPEFs). Ultra Scient phys Sci-Sect B 2011, 23(2), 449-58.

In the analysis of crystal binding based on the interionic force model, the contributing arising from coulomb interactions, the dipole-dipole (d-d) and dipole-quadrupole(d-q) interactions and the short-range repulsive interactions of the Hellmann and Varshni-Shukla interaction potential model. The calculated values of Gruneisen parameter,, Anderson Gruneisen parameter using two different formula for each parameter and Second Gruneisen parameter are reported here for alkali chalcogenide crystals(oxides and sulphides) of NaCl-structure. The high pressure behaviour of these crystals has also been studied. The graphical natures of calculated values I.R. absorption frequency-reduced mass and calculated values Debye temperature-reduced mass are also shown. The results obtained here may add a little to the physics and chemistry of these crystals.

5 illus, 2 tables, 46 ref

011875   Gaur K;Shalini;Singh S (NO, K.N. Govt. P.G. College, Gyanpur S.R.N., Bhadohi-221 304) : Transport studies on La, Ce and Pr nickelates. Ultra Scient phys Sci-Sect B 2011, 23(2), 275-84.

The electrical conductivity (ρ) and Seebeck coefficient (S) of. rare-earth nickelates of the type RNiO₃ with R = La, Ce and Pr are reported in the temperature range 400-1200K. These nickelates are perosskite type compounds with orthorhombic unit cell. It has been concluded that they are essentially electronic conductors and both the a and S variations with temperature (T) show three regions with break temperatures T₁ and T₂. The majority charge carriers are holes throughout the study. The conduction mechanism has been explained on the basis of energy band diagram. Energy band gap and mobility of charge carriers have also been evaluated.

4 illus, 5 tables, 25 ref

011874   Gaur K;Shalini;Satyendra Singh (NO, Faculty of Science K.N. Govt. P.G. College, Gyanpur S.R.N. Bhadohi) : Dielectric study of light rare-earth nickelates. Ultra Scient phys Sci-Sect B 2011, 23(1), 149-54.

Measurement of dielectric constant (K¹) and loss (K ) of light rare-earth nickelates of the type RNiO₃ with R = La, Ce, Pr, Ne, Sm and Eu have been reported in temperature range 300-1200 K. All the materials have been prepared in the laboratory by solid state reaction technique and characterised by XRD. Studied materials have high value of K and low value of K at lower temperature. However, at higher temperature increase becomes much faster and is due to space charge effect of thermally generated charge carriers. Temperature T₁ is different for different materials.

6 illus, 3 tables, 10 ref

011873   Dwivedi A K (Physics Dep, R.S.K.D.P.G. College, Jaunpur, U.P.) : Cylindrical shock wave in a gas cloud under the influence of radiation flux. Ultra Scient phys Sci-Sect B 2011, 23(1), 233-7.

In this paper the problem of explosion along a line in a gas cloud has been investigated. Similarity solutions have been developed describing the propagation of a cylindrical shock in non uniform atmosphere.

1 table, 14 ref

011872   Dwivedi A K (Physics Dep, R.S.K.D.P.G. College, Jaunpur, U.P.) : Self-similar model of weak shock wave in non-uniform atmosphere. Ultra Scient phys Sci-Sect B 2011, 23(1), 227-32.

In this paper author has studied the flow of a perfect gas behind a spherical wave, produced by a piston with a shock assumed to be propagating in a medium of non-uniform varying density. Isothermal and adiabatic cases are discussed.

2 tables, 20 ref

011871   Dubey S C;Shukla M K (Physics Dep, S.G.S. Govt. P.G. College, Sidhi, Madhya Pradesh-486 661, Email: subhas1236@rediffmail.com) : Effect of solar activity on recent climate change. Ultra Scient phys Sci-Sect B 2011, 23(2), 487-93.

The potential role of solar variations in modulating recent climate has been debated for many decades. Before the satellite period solar variability had been scaled from proxy data. So, the large uncertainty exists about potential role of solar variations in modulating recent climate. Recently, satellite observation/data and number of newly investigated solar features changes the old concepts. The Sun has a strong influence on climate. Important sources are cosmic rays which come from outer space and from the surface of the Sun, terrestrial radio-nuclides which occur in the earth's crust in various geological formations in soils, rocks, building materials, plants, water, food, air and in the human body itself. With the increasing use of radiation in health facilities, scientific research, industry and agriculture, the study of impact of low-level ionizing radiation on environment and possible health effects on future generations has been a cause of concern in recent years. The long-term trends in solar irradiance appear more plausible and produced modeled climates in better agreement. Solar activity varies on shorter-time scales, including the 11-year sunspot cycle and longer-term as Milankovitch cycle. The cyclical nature of the Sun's energy output is not yet fully understood; it differs from the very slow change that is happening within the Sun as it ages and evolves. In the present work, we have discussed effect of various solar influences to increase in greenhouse gases as well as climate change in the light of various latest studies.

2 illus, 12 ref

011870   Dubey G S;Shukla S (Physics Dep, G.S.P.G. College Samodhpur, Jaunpur, Uttar Pradesh) : Spherical and non-spherical gravitational collapse. Ultra Scient phys Sci-Sect B 2011, 23(3), 599-606.

Presented the singularity that may possibly form during the collapse, at the centre. We have discussed the nature of singularities in Husain solution. We have presented that under certain conditions of mass function, strong curvature naked singularities exist in spherically symmetric Husain solution. Even though in non-spherical cases, there are many examples of naked singularities. Also presented that non-spherical Husain solution also admits a naked singularity in special case, but in general it proceeds to form a black hole.

22 ref

011869   Dubey G S;Mishra K P (Physics Dep, G.S. P.G. College Samodhpur, Jaunpur, Uttar Pradesh) : On Bosonic and Fermionic fields. Ultra Scient phys Sci-Sect B 2011, 23(2), 299-304.

Authors presented that all the properties of the Bosonic cases are applicable to the Fermionic path integral. One may extend the derivation to multiple Fermi oscillators and to field theory. Renormalisation theory reads in the same way as for Bosonic path integral. Fermionic path integrals satisfy cutting relations. Insertion of ξ(t) and (t) in the path integral again gives the corresponding operator in the matrix element, and multiple insertions are time ordered.

18 ref

011868   Dash S K;Swain M D (DESM, Regional Institute of Education (NCERT), Bhubaneswar-751 022, Email: skdash59@yahoo.com) : Dipolar analysis of W-Q and D-D equations in tri-n-butyl phosphate with long chain aliphatic alcohols- excess mutual correlation factor and free energy of mixing. Ultra Scient phys Sci-Sect B 2011, 23(3), 709-16.

The mechanism of dipolar interaction involving the nuclear extractant TBP with five long-chain primary alcohols namely 1-butanol, 1-pentano, 1-hexanol, 1-heptanol and 1-octanol was investigated using measured value of the relative permittivity at 455kHz, refractive index at sodium D-line and density at temperature 303.16 K. The dielectric parameters such as excess mutual correlation factor and excess free energy of mixing were evaluated for entire range of concentration of TBP in these systems using Winkelmann-Quitzsch equation and Davis-Douheret equation. Striking similarities in the trend of variation of Δg and gab^-1, ΔF_WQ and ΔF_DD were observed in 1-hexanol, 1-heptanol, 1-octanol systems whereas it was opposite in others may be due to the limitations of W-Q and D-D equations.

3 illus, 18 ref

011867   Dangarh B K;Pensia R K;Shrivastava V;Patidar P (NO, Govt. P.G. College Neemuch, M.P., Email: vijayendra.shrivastava@hotmail.com) : Analysis of jeans instability of viscous, magnetized, partially-ionized plasma medium incorporating thermal conductivity, porosity and radiative heat-loss function. Ultra Scient phys Sci-Sect B 2011, 23(1), 59-76.

The problem of jeans instability of viscous, magnetized thermally conducting, partially-ionized gaseous medium in the presence arbitrary radiative heat-loss function has been investigated. With the help of relevant linearized perturbation equations of the problem using normal mode analysis, a general dispersion relation is obtained and the dispersion relation is discussed for longitudinal propagation in discussed separately.

20 ref

011866   Biswal S;Ray G S;Mishra P K (NO, , Plot No. 193, Jayadev Vihar, Bhubaneswar-13) : Hall effects on hydromagentic convective flow through a rotating porous channel with heat and mass transfer. Ultra Scient phys Sci-Sect B 2011, 23(1), 189-204.

Hall effects on combined free and forced convective flow of a viscous incompressible electrically conducting fluid between two horizontal perfectly conducting plates under the action of a uniform transverse magnetic field applied paralled to the axis of rotation has been analysed. Exact solution of the governing equation is obtained in closed form. It is observed that Hall current exerts stabilizing influence on the primary flow at the upper plate due to shear stress while at the lower plate Grashof number causes separation on the secondary flow. The interaction of wall porosity and Hall current greatly influence the flow field. The rate of heat transfer at both the plates are derived. It is found that the Hall current and rotation exert reverse flow of heat at the upper plate when the numerical value is equal to two as the Grashof number is being referred to. Mass transfer is also studied with the help of graph between concentration and channel length.

5 illus, 3 tables, 10 ref

011865   Barik U K;Pattnaik B K;Biswal S (Physics Dep, Jatani College, Jatani, Khurda) : Mass transfer effects on magnetohydrodynamic free convection flow of a visco-elastic fluid past an exponentially accelerated vertical porous plate. Ultra Scient phys Sci-Sect B 2011, 23(3), 579-90.

Effects of heat and mass transfer on MHD free convection, flow of a visco-elastico (Walters' B') fluid past an exponentially accelerated vertical porous plate have been studied. The problem is formulated with the development of the constitutive equations of continuity, momentum, energy and concentration. Solving the equations by Laplace transform technique, expressions for velocity, temperature and concentration are obtained. With the numerical values of the fluid parameters, computation is preformed and necessary graphs and tables are drawn to unveil the characteristics of velocity field, temperature field and concentration. Then expressions for shear stresses, rate of heat transfer and concentration gradient are obtained. It is observed that the velocity of flow increases with the distance from the plate for an externally cooled plate (G <62>0) and a reverse effect is marked for an externally heated plate (G<60>0). The temperature and concentration decreases with the increase of Prandtl number (P) and Schmidt number (S_c) respectively.

3 tables, 19 ref

013885   Singh S;Shrivastava D;Mishra A P (Physics Dep, A.P.S. Univ, Rewa, Madhya Pradesh, Email: shamrathore@yahoo.com) : Effect of solar and interplanet disturbances on space weather. Indian J scient Res 2012, 3(2), 121-5.

The environment of interplanetary medium near earth is dominated by the disturbances originating directly from the solar and interplanetary medium, such as solar flares, X-rays flares, coronal holes, CMEs and interplanetary magnetic field. Space-weather is significantly controlled by coronal mass ejections (CMEs), which can affect the earth in different ways. Moreover, the influence of solar phenomenon and associated interplanetary disturbances provide a unique opportunity to understand the correlation between solar, interplanetary and geomagnetic activity. The study of solar, interplanetary and geomagnetic parameters make possible to know the disturbances and impact on space weather interaction in the interplanetary magnetic field. In the present paper, we have analyzed the effect of solar and interplanetary plasma and field in relation to geomagnetic activity. The driving forces which are responsible to create disturbances in the space-weather have been investigated.

2 illus, 8 ref

013884   Singh R K;Mamta Kumari;Prasad J N (Physics Dep, R.L.S.Y. College, Ranchi, Jharkhand, Email: subrajon@yahoo.com) : Interaction of ferromagnet conduction electron spin with spatial and time varying magnetization. J Metall Mater Sci 2011, 53(2), 153-9.

Spin-dependent conduction and the magnetization dynamics of ferromagnets are at the centre of key mechanism in various spin electronics phenomena. The interaction of conduction electron spins with spatial and time varying magnetization M(r, t) in semi classical picture of transport were computed. The adiabatic approximation results in four spin torques- two each due to variation of magnetization in space and time. Each torque has different roles in magnetization dynamics.