Indian Journal of Pure and Applied Physics

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Volume 46

Number 10

OCTOBER 2008

CODEN : IJOPAU 46 (10) 675-748

ISSN : 0019-5596

 

 

 

CONTENTS

 

General

 

MHD free convection and mass transfer flow of a micro-polar thermally radiating and reacting fluid with time dependent suction

679

J Prakash*, A Ogulu & E Zhandire

 

The Physics of Elementary Particles and Fields

 

CKM-favored and -suppressed  and  meson decays to a pseudoscalar and a tensor meson

685

A C Katoch * & K K Sharma

 

Atomic and Molecular Physics

 

Phosphors MMgAl10O17: Eu,Dy (M=Ba,Sr,Ca) irradiated by Cs137 for thermoluminescence dosimetry

695

S J Dhoble*, G V Bramhe, R G Sonkawade & S V Moharil

 

FTIR and FT-Raman spectral investigation of 2-chloro-1,3-dibromo-5-fluorobenzene

698

G Ilango, M Arivazhagan*, J Joseph Prince & V Balachandran

 

Energy transfer between optically excited Tb3+ and Er3+ ions in zinc phosphate glass

702

B C Joshi*, D K Upreti, C C Dhondiyal & Bhawana Khulbey

 

Up-conversion luminescence application in Er3+: TiO2 thin film prepared by dip coating sol-gel route

706

Y Badr, I K Battisha*, A Salah & M A Salem

 

Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics and Fluid Dynamics

 

Molecular interactions of polymethyl methacrylate and polyethyeleneglycol solutions in tetrahydrofuran

712

M Selvakumar & D Krishna Bhat*

 

Condensed Matter: Structural, Mechanical and Thermal Properties

 

Thermal and electrical properties of MoO3-Bi2O3-B2O3 glasses

719

Sanjay N Kishore*, A Agarwal, V P Seth & M S Sheoran

 

 

 

High pressure study of structural and elastic properties of barium chalcogenides

722

Balwant S Arya, Mahendra Aynyas & Sankar P Sanyal*

 

Microwave absorption in PbHPO4 crystal

727

Trilok Chandra Upadhyay* & Subodh Gairola

 

Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties

 

Dielectric studies on some rubber materials at microwave frequencies

733

S Gunasekaran*, R K Natarajan, A Kala & R Jagannathan

 

Interdisciplinary Physics and Related Areas of Science and Technology

 

Development of low cost set up for anodic bonding and its characterization

738

C C Tripathi, Shruti Jain*, Pawan Joshi , S C Sood & Dinesh Kumar

 

__________

*The corresponding author has been indicated by (*) mark in case of papers with more than one author.

 

 

 

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 679-684

 

 

MHD free convection and mass transfer flow of a micro-polar thermally radiating and reacting fluid with time dependent suction

J Prakash*, A Ogulu1 & E Zhandire1

*Department of Mathematics, Faculty of Science

University of Botswana, Private Bag 0022, Gaborone, Botswana

1School of Physics, Westville Campus

University of KwaZulu-Natal Durban 4000, South Africa

E-mails: *prakashj@mopipi.ub.bw, 1ogulua@ukzn.ac.za, 1zhandiree@ukzn.ac.za

Received 20 February 2007; accepted 17 January 2008

The problem of free convection of a chemically reacting micro-polar fluid with mass transfer has been studied in the presence of a uniformly applied transverse magnetic field and variable suction. The governing, coupled, non-linear partial differential equations are solved employing a fourth order Runge-Kutta algorithm. The results show that the velocity increases as the suction parameter is increased, the chemical reaction rate decreases; while the angular velocity increases with increasing values of the suction parameter up to a point around y = 1.5, before the trend is reversed.

Keywords: Free convection, Micro-polar fluid, Variable suction

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 685-690

 

 

CKM-favored and -suppressed  and  meson decays to a pseudoscalar and a tensor meson

A  C  Katoch & K  K  Sharma*

Department of Physics, Shri Atmanand Jain College, Ambala City 134 002

*Department of Applied Sciences and Humanities, National Institute of Technology, A Deemed University,
Hamirpur 177005, Himachal Pradesh

E-mail: kks@nitham.ac.in

Received 29 October 2007; revised 18 June 2008; accepted 29 July 2008

The two-body  and  meson decays emitting a pseudoscalar and a tensor meson in the final state, using the factorization hypothesis have been investigated. We employ the Isgur, Scora, Grinstein and Wise quark model to evaluate the form-factors entering the decay amplitudes. Though many decay channels are available forand  meson decays, the dominant ones are: , , and  which have the branching ratios (%) of the  order of  . To the next order dominant decays are  , ,  and ,  and  and , which have branching ratios (%) of the order of . We hope that the calculated branching ratios are within the reach of current experiments.

Keywords: Mesons, Meson decays, Pseudoscalar, Tensor meson, Quark model

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 695-697

 

 

Phosphors MMgAl10O17: Eu,Dy (M=Ba,Sr,Ca) irradiated by Cs137 for thermoluminescence dosimetry

S J Dhoble, G V Bramhe 1, R G Sonkawade 2 & S V Moharil3

Kamla Nehru College, Sakkardara Square, Nagpur 440 009

1Govt Autonomous P G College,Chhindwara 480 001

2Nuclear Science Center, New Delhi 110 067

3Department of Physics, RT M Nagpur University , Nagpur 440 033

Received 6 June 2008; accepted 29 July 2008

The thermoluminescence (TL) of Eu, Dy activated M MgAl10O17[M=Ba,Sr,Ca] phosphors has been reported in this paper. These phosphors are prepared by combustion synthesis. TL glow intensity of these phosphors is higher as compared to conventional CaSO4:Dy TL-phosphor. M MgAl10O17[M=Ba,Sr,Ca] phosphors may be the possible candidate for thermoluminescence dosimetry of ionizing radiations.

Keywords: Thermoluminescence, Dosimetry, Phosphors, Luminescence

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 698-701

 

 

FTIR and FT-Raman spectral investigation of
2-chloro-1,3-dibromo-5-fluorobenzene

G Ilangoa, M Arivazhaganb, J Joseph Princec & V Balachandranb

a Department of Physics, M A M College of Engineering, Tiruchirappalli 621 105

b Department of Physics, A A Govt. Arts College, Musiri 621 201

c Department of Physics, Anna University, Tiruchirappalli 620 024

Received 11 February 2008; revised 1 August 2008; accepted 8 September 2008

normal coordinate calculations of 2-chloro-1,3-dibromo-5-fluorobenzene have been carried out using Wilson’s FG matrix mechanism on the basis of General Valence Force Field (GVFF) for both in-plane and out-of-plane vibrations. The potential energy constants obtained in this study are refined using numerical methods.

Keywords: FTIR, FT- Raman spectra, chloro-bromo-fluorobenzene, normal coordinate analysis, potential energy distribution

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 702-705

 

 

Energy transfer between optically excited Tb3+ and Er3+ ions in zinc
phosphate glass

B C Joshi, D K Upreti1, C C Dhondiyal & Bhawana Khulbey

Department of Physics, Kumaun University, S S J Campus, Almora (Uttarakhand)

E-mail: dkupreti17@yahoo.co.in

Received 7 November 2007; revised 1 August 2008; accepted 9 September 2008

A study of energy transfer from optically active ions Tb3+ to Er3+ in zinc phosphate glass has been made. The evidence of non-radiative energy transfer has been noted from the decrease of Tb3+ emission with increasing Er3+ concentrations. Energy transfer mechanism is mainly found to be electric dipole-dipole in nature. Various parameters such as energy transfer probability, transfer efficiency and average donor-acceptor distances have been computed.

Keywords: Energy transfer, Sensitization, Fluorescence, Donor, Acceptor, Rare earths

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 706-711

 

 

Up-conversion luminescence application in Er3+: TiO2 thin film prepared by dip coating sol-gel route

Y  Badr,  I  K  Battisha, A  Salah & M  A  Salem

*National Institute of Laser Enhancement Sciences (NILES), Cairo University, Egypt

**National Research Center (NRC) Department of Solid State Physics, Cairo, Egypt

E-mail: szbasha@yahoo.com

Received 26 December 2007; revised 6 February 2008; accepted 13 March 2008

Sol-gel derived nano-crystalline titanium dioxide films doped with 1 up to 5% Er3+ ions were prepared by dip coating sol-gel method. The coating sol was obtained by hydrolysis of Ti(OC4H9)4 in ethanol/HCl solution. The FT-Raman and the X-ray diffraction (XRD) were carried out to determine the crystal structure of the prepared samples. The morphology SEM and the cross – sectional of the film were used to characterize the microstructure and the thickness of the prepared film. It is shown that  relative homogeneous, crack-free and transparent film was achieved via dipping process at 500oC.After the excitation with laser diode at wavelength 808 nm, visible (Vis) and infrared (IR) up-conversion emissions were evidenced in the thin film samples under investigation. The up-conversion was found to depend strongly on the Er3+ ion concentrations. The visible emission was found to be at 540, 560, 590 and 640 nm for thin film. They are attributed to intra-4f transition of Er3+ ions and assigned to the (2H11/2 + 4S3/2) and 4F9/2, which are populated through excited state absorption (ESA) for 808 nm excitation.

Keywords: Dip coating sol-gel technique, Thin film, Up-conversion, XRD, Anatase , FT-Raman

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 712-718

 

 

Molecular interactions of polymethyl methacrylate and polyethyeleneglycol solutions in tetrahydrofuran

M Selvakumar & D Krishna Bhat*

 Department of Chemistry, National Institute of Technology, Karnataka 575 025

*E-mail: denthaje@gmail.com

Received 16 January 2008, revised 8 August 2008; accepted 10 September 2008

The ultrasonic velocity, density and viscosities of the polymethylmethacrylate (PMMA) and polyethyleneglycol (PEG) solutions in tetrahydrofuran (THF) have been measured in the temperature range 293-313K. Using these data, free energy of mixing, solvation number and different polymer-solvent interaction parameters for the solution systems have been calculated to know the presence of molecular interactions in the system. The trends in the variation of the solution property parameters indicate the existence of positive molecular interactions between the polymer and the solvent in solutions. The results also show the presence of higher degree of interaction between PEG and THF in solution compared to PMMA and THF.

Keywords: Polymer solutions, Ultrasonic velocity, Viscosity, Interaction parameter, Miscibility, PMMA, PEG, THF

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 719-721

 

 

Thermal and electrical properties of MoO3-Bi2O3-B2O3 glasses

Sanjay N Kishore, A Agarwal, V P Seth & M S Sheoran

Department of Applied Physics, Guru Jambheshwar University of Science and Technology, Hisar 125 001

E-Mail:- sanjay2000angira@yahoo.co.in

Received 28 October 2007; revised 15 May 2008; accepted 1 August 2008

Semiconducting oxide glasses of compositions xMoO3.(40-x)Bi2O3.60B2O3 have been prepared by the standard melt-quenching technique over the range 0 ≤ x ≤ 10 (x is in mol%). The various properties such as glass transition temperature, density, molar volume and dc conductivity have been measured. The values of characteristic glass transition temperature (Tg) have been found from differential scanning calorimetry (DSC) traces and corresponding specific heat capacity (Cp) was also estimated. It is found that the density of these glasses decreases as MoO3 content is increased due to lower degree of cross-bonding between molybdenum and non-bridging oxygen ions resulting in a weakening of glass network. The dc conductivity of these samples was measured in the temperature range 523-623K. In this temperature range, the dc conductivity increases from 10-9 to 10-8 S/m with increasing MoO3 content. The values of the theoretical optical basicity of these glasses have also been determined.

Keywords: Glasses, Glass transition temperature, Transition metal ions, dc conductivity

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 722-726

 

 

High pressure study of structural and elastic properties of barium chalcogenides

Balwant SArya1, Mahendra Aynyas2 & Sankar P Sanyal3,*

1Department of Physics, Govt. Narmada College, Hoshangabad 461 001

2Department of Physics, S. V. College, Bhopal 462 030

3 Department of Physics, University of Bhopal, Bhopal 462 026

3Email: aynyas@rediffmail.com

Received 9 October 2007; revised 17 April 2008; accepted 10 July 2008

The structural and elastic properties of barium chalcogenides (BaX; X = S, Se, Te) under high pressure have been investigated by using a two body inter-ionic potential approach with modified ionic charge (Zme). The equation of states in NaCl type to CsCl type structural phases for BaX  has been depicted and found that the volume collapses at the phase transition pressures. The phase transition pressures 7.2 GPa, 6.1 GPa, 5.0 GPa respectively for BaS, BaSe, and BaTe obtained by us, are in close agreement with experimental data (6.5 GPa, 6.0±0.2 GPa, 4.8±0.3 GPa). The  bulk modulus, pressure derivatives, second order elastic constants (SOEC) and third order elastic constants (TOEC) at high pressure have been calculated, which show predominantly ionic nature of these compounds. The variation of second order elastic constants (C11, C44) with pressure has been presented.

Keywords:  High pressure, Elastic properties, Phase transition

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 727-730

 

 

Microwave absorption in PbHPO4 crystal

 

Trilok Chandra Upadhyay* & Subodh Gairola

Physics Department, H N B Garhwal University, Srinagar (Garhwal), Uttarakhand 246 174

Received 2 November 2006; revised 4 April 2008; accepted 10 June 2008

Considering two-sublattice pseudospin lattice coupled mode model along with third- and -fourth order phonon anharmonic interaction terms and using double-time thermal Green's function method for PbHPO4 crystal, expressions for shift, width, renormalized soft mode frequency, Curie temperature, dielectric constant and microwave absorption have been derived. By fitting model values in expressions, numerical values of soft mode frequency dielectric constant and loss tangent (microwave absorption) have been calculated. Theoretical results compare well with experimental results of Ohno and Lockwood [Ferroelectrics, 72 (1977)303] and Negran et al. [Ferroelectrics, 6 (1974) 179].

Keywords:      Microwave absorption, PbHPO4 crystal, Ferroelectrics

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 733-737

 

 

Dielectric studies of some rubber materials at microwave frequencies

S Gunasekaran, R K Natarajan1, A Kala1*& R Jagannathan2

PG and Research Department of Physics, Pachaiyappa’s College, Chennai 600 030

1PG and Research Department of Physics, Presidency college, Chennai 600 005

2Department of Physics, D G Vaishnav College, Chennai 600 106

Received 3July 2007; revised 20 October 2007; accepted 7 February 2008

Studies on dielectric property of natural rubber (NR) and some synthetic rubbers viz., styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR), ethylene propylene diene monomer (EPDM), ethyl vinyl acetate rubber (EVA), PVC nitrile, butyl rubber, silicon rubber, neoprene, chlorosulphonated monomer, polyacrylic, fluorocarbon rubber, reclaimed rubber and polyblends of natural rubber with NBR and EPDM were carried out using microwave test bench system at X-band and K-band microwave frequencies. Analysis of dielectric property is inevitable since they determine the end electrical applications, per se, insulation. Present work is aimed at the determination of dielectric constant by using the method proposed by Robert and Von-Hippel. A systematic analytical approach was adopted in evaluating the data generated on dielectric constants for a variety of rubber materials. Interesting results were obtained by comparing dielectric constant values. The effect of microwave frequency, namely 9.6 GHz and 26GHz, as well as chemical modification brought about by vulcanization and reinforcement on dielectric constant values was probed. It appears from the study that among all samples polyblend of NR with EPDM posses interesting dielectric behaviour making it unique.

Keywords: Rubber materials, Dielectric constant, Microwave frequency, X- band, K- band

 

 

Indian Journal of Pure and Applied Physics

Vol.46, October 2008, pp 738-743

 

 

Development of low cost set up for anodic bonding and its characterization

C C Tripathi+, Shruti Jain+, Pawan Joshi+, S C Sood+ & Dinesh Kumar*

+Ambala College of Engineering. & Applied Research, Devasthli, Ambala

+E-mail: jain.shruti15@gmail.com

*Electronic Science Department, Kurukshetra University, Kurukshetra

Received 3 September 2007; revised 3 January 2008; accepted 3 April 2008

A low cost experimental set- up for anodic bonding has been developed indigenously in the college laboratory and glass silicon bonding parameters characterized. Anodic bonding between silicon and glass substrates has been characterized in detail. The effects of magnitude of the applied voltage on the time required for complete bonding have also been investigated. The effect of voltage, point contact, bond strength and electrostatic force in anodic wafer bonding process has also been analyzed. The glass to silicon bonding at 1150V, 450ºC has been successfully performed. This enables simple, but highly accurate, alignment of pre-patterned glass and silicon wafers. Fabricated devices have wide benefits like glass transparency at optical wavelengths

Keywords: Low cost set-up, Silicon glass bonding

 

 

 

 

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