Indian Journal of Pure and Applied Physics

 

ISSN: 0019-5596   CODEN:IJOPAU 41(2) 85-156(2003)
VOLUME 41  

 NUMBER 2

FEBRUARY  2003

                                                                                                                                                                                                           

CONTENTS

 

 

The Physics of Elementary Particles and Fields

Static properties of hadrons from MIT bag model with interacting quarks

A A Rajabi

 

89

Atomic and Molecular Physics

Normal coordinates analysis of vibrational spectra of 2-methylindoline and 5-hydroxyindane

V Krishnakumar* & R John Xavier

 

95

Scattering of protons and antiprotons by hydrogen-like atoms

Reda S Tantawi

100

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

Ultrasonic relaxation in some viscoelastic liquids

A V Narasimhan

 

105

Ultrasonic speeds and isentropic functions of mixtures of N-methyl-2-pyrrolidinone and branched alcohols at 298.15 K

Amalendu Pal*, Harsh Kumar, B R Arbad & A B Tekale

 

113

Viscosity and thermal conductivity of gas mixtures

Kuldip Singh* & N K Sood

121

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

Effect of pre-thermal treatments on thermoluminescence of synthetic quartz

P R Vyas*, Y H Gandhi & T R Joshi

 

128

Optical properties of SnTexSe1-x thin films

L I Soliman*, B S Farag, H A Zayed & F M Shehata

131

Some physical properties of Ga2Te5 single crystals

 M M Nassary*, M K Gerges, H T Shaban & A S Salwa

139

Interdisciplinary Physics and Related Areas of Science and Technology

Application of Mossbauer spectroscopy to study the effect of fly-ash in agriculture soil

Roshan Lal & N D Sharma*

 

145

Wavelength converters in WDM networks – An improvement in call connection probability

S Harissh, T R Chandramouli & V K Chaubey*

149

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

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 89-94

 

Static properties of hadrons from MIT bag model
with interacting quarks

A A Rajabi

Physics Department, Shahrood University, 7-Tir Sq, PO Box 36155-316, Shahrood, Iran

 

Received 26 March 2002; revised 1 October 2002; accepted 15 November 2002

 

 

An improved MIT bag model is used to calculate the static properties of hadrons containing u,d , s and c quarks. The two key ingredients of the improved model are the effective quark-gluon coupling constant originating from color charge and the quark confinement. In this paper, the authors choose to allow residual interactions to operate so as to go beyond of asymptotic freedom and confinement. In the model used, the valence quarks interact with themselves. The authors calculate the relativistic wave-function for quarks in a scalar-vector QCD potential, analytically. Finally, vanishing of the normal component of vector current at the surface of the baryon as a boundary condition equivalent to confinement results in the static properties and the strength of Coulomb like potential parameter. This depends on the mass parameters, contrary to almost all previous versions. The calculated static properties for baryon is better than in the uncorrected versions of the model. Magnetic moments and charge radii of some hadrons are comparable well with the experiment. The agreement for the magnetic moments is surprisingly good for n, , -, +…..

 

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 95-99

 

Normal coordinate analysis of vibrational spectra of
2-methylindoline and 5-hydroxyindane

V Krishnakumar & R John Xavier*

Post-graduate Department of Applied Physics, Nehru Memorial College, Puthanampatti 621 007

*Department of Physics, JJ College of Engineering and Technology, Tiruchirappalli 620 009

 

Received 16 May 2002; revised 9 August 2002

 

 

The normal coordinate analysis of 2-methylindoline and 5-hydroxyindane has been carried by assuming Cs point group symmetry. The potential energy constants are obtained by applying Wilson’s FG matrix method. The potential energy distribution has also been calculated to check the validity of the assignments proposed in this study.

 

 

 

Indian J Pure & Applied Physics

Vol. 41, February 2003, pp. 100-104

 

 

Scattering of protons and antiprotons by hydrogen-like atoms

Reda S Tantawi

Department of Mathematics, Faculty of Science, Zagazig University, Zagazig, Egypt

 

Received 1 April 2002; revised 20 December 2002; accepted 13 January 2003

 

 

The impact parameter method is applied to the excitation of hydrogen-like atoms in the 2s-state. Cross-sections for the n=3 excitation of H(2s) atoms and H+(2s), Li+(2s) ions, by colliding with protons (p) and antiprotons are evaluated for incident energies, ranging from 1.5 KeV to 2500 KeV. The results of calculations for hydrogen atoms are compared with a previous work.

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 105-112

 

Ultrasonic relaxation in some viscoelastic liquids

*A V Narasimhan

Guest Professor of Physics, Sri Sai Ram Engineering College, Chennai 600 044

 

Received 12 July 2002; revised 25 November 2002; accepted 8 January 2003

 

 

Expressions are worked out for the ultrasonic relaxation times in viscoelastic liquids, using their compressibiity (an elastic property) and bulk viscosity coefficient (a viscous property), giving equations for the compressional and bulk viscous relaxation times in these viscoelastic liquids. Available experimental data in three viscoelastic liquids, are used to calculate these ultrasonic relaxation times, which depend upon the low, mid and high frequency wave velocities and the absorption of the wave in the medium. The complex wave velocity (Indian J Pure & Appl Phys, 12 (1974) 557) is connected with the complex compressibility of the liquid, while Navier–Stokes equations of hydrodynamics (IEEE Trans on Sonics & Ultrasonics, SU 16 (1969), 182) are connected with the real and imaginary parts of the complex, bulk viscosity coefficient of liquid, leading to equations for the aforesaid relaxation times and their evaluation, using experimental data. The variations of velocity, absorption and relaxation times with temperature have been discussed. Temperature variations of relaxation times have been discussed and are used to evaluate the molecular activation energies in the liquid. The magnitudes of the activation energies are found to be reasonable. The agreement between theory and experimental data seems to be better for compressional relaxation, than for relaxation associated with bulk viscosity of the liquid. It seems that, the data can be resolved into more than one relaxation group and activation energy (two or even more) leading to a distribution of relaxation times in these viscoelastic liquids.

 

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 113-120

 

 

Ultrasonic speeds and isentropic functions of mixtures of
N-methyl-2-pyrrolidinone and branched alcohols at 298.15 K

Amalendu Pal*a, Harsh Kumara, B R Arbadb & A B Tekaleb

aDepartment of Chemistry, Kurukshetra University, Kurukshetra 136 119

bDepartment of Chemistry, Dr B A Marathwada University, Aurangabad 431 004

*[e-mail: search@vidya.kuk.ernet.in]

 

Received 8 February 2002; revised 9 September 2002; accepted 1 November 2002

 

 

Ultrasonic speeds have been measured for binary mixtures of N-methyl-2-pyrrolidinone with 2-propanol, 2-methyl-1-propanol, 2-methyl-2-propanol, and 3-methyl-1-butanol, as a function of composition at 298.15 K. The values have been combined with those of densities derived from excess molar volumes to give estimates of the product KS,m of the molar volumes and the isentropic compressibility S and the excess quantity . The values are negative over the entire range of composition for all mixtures. The deviations uD of the speeds of sound from their values in an ideal mixture were also evaluated for all measured mole fractions. Graphs of uD, and against composition are presented as a basis for a quantitative discussion of the results. Various thermodynamic parameters have been derived from the speed of sound data. Theoretical values of speeds of sound u have also been determined using empirical relations.

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 121-127

 

 

Viscosity and thermal conductivity of gas mixtures

Kuldip Singh & N K Sood

Department of Physics, Guru Nanak Dev University, Amritsar 143 005

 

Received 29 April 2002; accepted 26 August 2002

 

 

A method is proposed for estimating viscosity and thermal conductivity of gas mixtures from the pure component data. Deviations of the results predicted by the approximate relationships developed are of the same order, as the uncertainty in the experimental measurements.

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 128-130

 

 

Effect of pre-thermal treatments on thermoluminescence of
synthetic quartz

P R Vyas

Government Polytechnic, Chhotaudepur, Dist. Baroda, Gujarat 391 165

and

Y H Gandhi & T R Joshi*

*Applied Physics Department, Faculty of Technology and Engineering, MS University of Baroda, Vadodara 390 001

 

Received 3 May 2002; revised 5 August 2002; accepted 2 September 2002

 

 

The effect of pre-thermal treatments on the thermoluminescence (TL) characteristics of synthetic quartz has been investigated. Various gamma dose exposure was given to the sample after thermal pre-treatment. The systematic variation in TL glow curves with different pre-thermal treatment is discernible. In a most significant observation it was found that, TL intensity enhanced abruptly, when the specimen was pre-heat treated at 600 C. This observation is explained on the basis of phase transformation in synthetic quartz.

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 131-138

 

 

Optical properties of SnTexSe1-x thin films

L I Soliman & B S Farag

National Research Centre, Cairo, Egypt

and

H A Zayed & F M Shehata

University College for Art, Science & Education, Ein Shams University, Cairo, Egypt

 

Received 5 December 2001; revised 29 July 2002; accepted 20 December 2002

 

 

Ternary alloys of SnTexSe1-x (0 x  1) were synthesized by direct fusion method. The SnTexSe1-x films were prepared by thermal evaporation under vacuum of about 10-5 torr and with evaporation rate of about 30 nm/min. X-ray diffraction and microprobe analysis technique, investigated the structural and the composition analysis of SnTexSe1-x in powder and thin film forms, respectively. X-ray diffraction patterns of the as-deposited and the annealed films of this system reveal that, these have polycrystalline nature of orthorhombic structure for alloys with compositions x = 0, 0.2, and 0.4 and cubic structure for alloys with compositions x = 0.6, 0.8 and 1. The variation of lattice parameters with different compositions x were also determined. The optical constants (the refractive index n, the absorption index k, the absorption coefficient , the dielectric constants 1 and 2) of SnTexSe1-x films were determined for different thickness in the spectral range 500-2500 nm. The optical absorption results indicate that, the fundamental absorption edge for SnTexSe1-x (0 x  0.6) films is due to an allowed, direct and indirect transition energy gaps and only direct energy gap for 0.8 x  1. It was found that, the optical energy gaps for annealed films decreased as compared with the as-deposited films. This decrease of the energy gaps is attributed to the change in the structure of the films from amorphous to crystalline. The variations of the optical constants (n, k, 1 and 2) with composition were investigated.

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 139-144

 

 

Some physical properties of Ga2Te5 single crystals

M M Nassary*, M K Gerges, H T Shaban & A S Salwa

Physics Department, Faculty of Science, South Valley University, Qena, Egypt

(E-mail: Nassary_99@Yahoo.com)

 

Received 29 May 2002; revised 4 December 2002; accepted 20 December 2002

 

 

Single crystals of Ga2Te5 were prepared by a special modified Bridgman technique. Measurements of the electrical conductivity and Hall effect between 268 and 503 K were carried out on Ga2Te5 samples, in two crystallographic directions (parallel and perpendicular to the C-axis). The Hall coefficient is positive and varies with the crystallographic direction. A unique mobility behaviour and strong anisotropy in the carrier mobility were observed. Also, the present investigation involves the thermoelectric power measurements of Ga2Te5 samples, in the wide range, from 170 to 511 K, when the direction of the temperature gradient is parallel to the layer planes. The combination of the electrical and thermal measurements in the present investigation makes it possible to find various physical parameters such as, carrier mobilities, effective masses of free charge carriers (m*p, m*n), diffusion coefficient (Dp, Dn) and diffusion length (Lp, Ln), as well as the relaxation time (τp, τn) and to reveal the general behaviour of this semiconductor.

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 145-148

 

 

Application of Mossbauer spectroscopy to study
the effect of fly-ash in agriculture soil

Roshan Lal & N D Sharma

Department of Physics, Kurukshetra University, Kurukshetra 136 119

 

Received 16 August 2002; revised 20 December 2002

 

 

57Fe Mossbauer spectroscopy has been used to study the fly-ash of Panipat Thermal Power Station, Panipat and the various samples of agriculture soil where the effluent water is used for irrigation in the adjoining areas of the Thermal Power Plant. The fly-ash sample shows only Fe2+ state. When the effluent water is used for irrigation, then fly-ash flows with water and gets added in the agriculture soil and thereby increases the Fe2+/Fe3+ ratio in the soil. The Fe2+/Fe3+ ratio in these samples has been determined. These results indicate that, the effluent water, when used for irrigation improves plant nutrition and the growth of the crops is good and hence reduces the applicability of artificial fertiliser up to some extent.

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 41, February 2003, pp. 149-152

 

 

Wavelength converters in WDM networks –
An improvement in call connection probability

S Harissh, T R Chandramouli & V K Chaubey

Electrical & Electronics Engineering Department, Birla Institute of Technology and Science, Pilani, Rajasthan 333 031

 

Received 5 June 2002; revised 9 September 2002; accepted 26 November 2002

 

 

Call connection probability in an all optical network (AON) using wavelength division multiplexing (WDM) depends on the number of WDM wavelengths available in a link and on the network capability for wavelength conversion at network nodes. A simpler approach for calculation of call connection probability using wavelength converters has been provided. Expressions for call connection probability, with and without wavelength converters are derived and are combined in a converter availability model, so as to study the impact of wavelength conversion on call connection probability.