Indian Journal of Pure and Applied Physics

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VOLUME 47

NUMBER 7

JULY 2009

CODEN:IJOPAU 47(7) 467-542

 

ISSN:0019-5596

 

CONTENTS

 

Atomic and Molecular Physics

 

 

Gamma ray interaction with lithium borate glasses containing WO3

471

        Fatma H ElBatal*

 

 

Molecular structure, vibrational spectroscopic studies and analysis of 2-fluoro-5-methylbenzonitrile

481

        N Sundaraganesan*, G Elango, S Sebastian & P Subramani

 

 

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

Dynamics  

 

 

 

Construction of all digital closed-loop interferometric fiber optic gyroscope with erbium doped fiber amplifier

 

491

        Oğuz Çelikel* & S Eren San

 

 

 

Condensed Matter: Structural, Mechanical and Thermal Properties

 

 

Application of rigorous infinitesimal deformation approach to martensitic transformation observed in some Fe-Ni-C alloys

 

501

        A Dogan & Y Havvatoglu*

 

 

Screw twinning in monoclinic zirconia

506

        M Arshad Choudhry* & M Zafar Javed

 

 

Volumetric and transport properties of binary liquid mixtures of aromatic hydrocarbons with
N-methylacetamide at 308.15 K

 

511

        B Ranjith Kumar, B Satyanarayana, S Asra Banu, K Amara Jyothi, T Savitha Jyostna &
N Satyanarayana*

 

 

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

 

 

  Automated measurements of junction characteristics to evaluate parameters for semiconductor diodes

  517

        P K Patel, V A Kheraj, C J Panchal*, M S Desai, P D Vakil & K J Patel

 

 

Hot electron scattering rates via LO-phonon emission in two-dimensional GaAs1-xNx

523

        Ankur Pandya, Satyam Shinde & Prafulla K Jha*

 

 

Forced oscillator model for entropic potential in the context of superconductivity

527

        Z Bousnane* & M Benslama

 

 

Electrical and optical properties of azo dye

530

        M S Aziz & H M El-Mallah*

 

 

Interdisciplinary Physics and Related Areas of Science and Technology

 

 

Current-mode biquad employing single CDTA

535

        D Biolek*, V Biolkova & Z Kolka

 

 

Authors for correspondence are indicated by (*)

 

 

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 471-480

 

 

Gamma ray interaction with lithium borate glasses containing WO3

 

Fatma H ElBatal*

Glass Research Department, National Research Center Dokki, Cairo, Egypt

*E-mail: fh_elbatal@yahoo.co.uk

Received 2 December 2008; revised 4 February 2009; accepted 8 May 2009

Glasses from the system of undoped lithium diborate and WO3-doped were synthesized by the usual melting and annealing techniques. UV-visible absorption spectra of the prepared sample were measured before and after successive gamma irradiation. Undoped glass reveals strong UV absorption spectrum which is related to the presence of unavoidable trace iron impurity. The presence of tungsten ions in this glass system is observed to impart no colour or marked changes in the absorption spectrum of the host glass suggesting the presence of tungsten ions mostly as W6+ species. Gamma irradiation produces extended induced bands in the UV-visible regions in the undoped and WO3-doped glasses. These induced bands are related to the presence of intrinsic defects already present in the host lithium diborate glass and extrinsic defects due to the presence of both trace iron impurity and tungsten ions. Infrared absorption spectra reveal specific vibrational bands due to characteristic borate network beside modifier lithium ions (Li+) and tungsten groups. Raman spectra confirm the IR results regarding the presence of tungsten ions mainly as WO6 groups due to the oxidizing nature of the host glass. Tungsten ions are seen to cause shielding or retardation of the growth of the induced bands by gamma irradiation.

           Keywords: Lithium diborate glass, WO3, UV-visible spectroscopy, Gamma rays, IR-Raman, ESR spectroscopy

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 481-490

 

 

Molecular structure, vibrational spectroscopic studies and analysis of
2-fluoro-5-methylbenzonitrile

 

N Sundaraganesana*, G Elangoa, S Sebastiana & P Subramanib

aDepartment of Physics (Engg.), bDepartment of Chemistry Annamalai University, Annamalai Nagar 608 002

E-mail: sundaraganesan_n2003@yahoo.co.in

Received 29 October 2008; revised 12 March 2009; accepted 30 April 2009

Quantum mechanical calculations of energies, geometries and vibrational wavenumbers of 2-fluoro-5-methyl-benzonitrile (2F5MBN) 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 sets. The optimized geometrical parameters obtained by DFT calculations are found to be in good agreement with experimental X-ray data. The best level of theory in order to reproduce the experimental wavenumbers is B3LYP method with the 6-311++G(d,p) basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared and Raman spectra of 2F5MBN has also been reported. The entropy of the compound under study is also performed at /B3LYP/ 6-311++G(d,p), cc-pvdz, Aug-cc-pvdz levels. The theoretical spectrogram for FT-IR and FT-Raman spectra of the molecule have been constructed.

KeywordsMolecular structure, Vibrational spectroscopy, Quantum mechanical calculations, Benzonitrile,
Density functional theory

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 491-500

 

 

Construction of all digital closed-loop interferometric fiber optic gyroscope
with erbium doped fiber amplifier

 

Oğuz Çelikel1* & S Eren San2

1*Tubitak Ume Optics Laboratory, Fiber Optic Metrology Division, P O Box: 54 41470 Gebze-Kocaeli/Turkey

2Gebze Institute of Technology (GYTE) Department of Physics 41400 Gebze, Kocaeli/Turkey

E-mails: 1*oguz.celikel@ume.tubitak.gov.tr ; 2erens@gyte.edu.tr

Received 25 August 2008; revised 16 April 2009; accepted 11 May 2009

This paper describes the design details and the characterization of an all digital closed-loop (ADCL) Interferometric Fiber Optic Gyroscope (IFOG) Prototype with sine wave biasing modulation and an erbium doped fibre amplifier (EDFA) pumped by DFB laser emitting at 1549.0 nm as a broadband source. The output of demodulation circuit in the prototype, proportional to the applied rotation rate, was sampled by AD7714YN analog to digital converter (ADC) and operated in 16 bit resolution. Error voltage, generated by microcomputer-controlled LTC 1667CG, 14 bit digital to analog converter (DAC), was sent to the phase modulator through a linear summing circuit, to make Sagnac Phase Shift zero, depending on the rotation direction. The averaged sensitivity of the ADCL-IFOG prototype in unit of error voltage applied to the phase modulator was calculated as 129.21 mV/(°/h) which equals to a scale factor of 7.739 (°/h)/(mV) with a standard deviation of 0.71% for a range of 1-15270 (°/h) rotation rate, corresponding to a range of Sagnac Phase Shifts varying from 0.00115 (°) to 17.57448 (°).The maximum peak to peak noise and the bias stability of the prototype were determined as 3.88 (°/h) and 1.38 (°/h) at 23.0°C, respectively.

Keywords: All digital closed-loop IFOG, Open-loop IFOG, Sagnac Phase, EDFA, Scale factor, Bias modulation

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 501-505

 

 

Application of rigorous infinitesimal deformation approach to martensitic transformation observed in some Fe-Ni-C alloys

 

A Dogan & Y Havvatoglu*

Kahramanmaras Sutcuimam University, Faculty of Science and Arts, Department of Physics, 46100, K Maras, Turkey

*E-mail: yhavvat@ksu.edu.tr

Received 26 March 2009; accepted 8 May 2009

Rigorous infinitesimal deformation approach has been used to predict the phenomenological crystallographic parameters such as amount of lattice invariant shear, magnitude of total shape deformation, orientations of habit planes, etc. associated with martensitic phase transformation fcc to bct observed in the alloy Fe-22Ni-0.8C and Fe-29.37Ni-0.34C. The values obtained for the crystallographic parameters in the present study and those from the infinitesimal deformation (ID) approach and experiments have been compared with one another.

Keywords: Rigorous infinitesimal deformation approach, Fe-Ni-C alloys, Crystallography, Martensite phase transformations

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 506-510

 

 

Screw twinning in monoclinic zirconia

 

M Arshad Choudhry* & M Zafar Javed**

Department of Physics, The Islamia University of Bahawalpur, Pakistan

*E-mail: drmarshadch@yahoo.com

**E-mail: mzafarjaved@gmail.com

Received 10 December 2008; revised 9 April 2009; accepted 4 May 2009

A geometrical approach based on the criteria of minimum shuffling after the simple shear and least distortion in bonding is used to find out the acceptable twin boundary structures for  (100) and (001) twins in monoclinic zirconia. Possible twin boundary structure for (100) and (001) twins are suggested. The proposed structure for twinning on (100) is within an orientation which can be described as a rotation of π about η1 plus translation of (1/2)c or reflection in K1 plus a (1/2)b glide. The proposed structure for (001) twin is in an orientation which can be described as rotation of π about η1 plus translation of (1/2)a or reflection in K1 plus a (1/2)b glide. These orientation relations are not those which are classically defined for deformation twinning. This may be termed as screw  orientation  relation.

Keywords: Twinning, Orientation relation, Zirconia

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 511-516

 

 

Volumetric and transport properties of binary liquid mixtures of aromatic hydrocarbons with N-methylacetamide at 308.15 K

 

B Ranjith Kumar, B Satyanarayana, S Asra Banu, K Amara Jyothi, T Savitha Jyostna & N Satyanarayana*

Department of Chemistry, Kakatiya University, Warangal 506 009, Andhra Pradesh

*E-mail: nallani_s@yahoo.com

Received 11 November 2008; revised 12 March 2009; accepted 25 May 2009

Experimental data on density, viscosity and speed of sound values at 308.15 K are presented for the binary mixtures of N-methylacetamide with benzene, toluene, mesitylene and phenylacetonitrile. From these experimental data, excess molar volumes, deviations in viscosity and isentropic compressibility of aromatic hydrocarbons with N-methylacetamide have been calculated. The computed values have been fitted to Redlich-Kister polynomial equation using multiparametric non-linear regression analysis to estimate the coefficients and standard errors. The variations in the calculated excess quantities for these mixtures have been studied in terms of molecular interactions between the component liquids and the effects of methyl and cyanomethylene substitution on benzene ring.

Keywords: Excess volumes, Viscosity deviations, Isentropic compressibility deviations, Binary mixtures, N-methylacetamide, Aromatic hydrocarbons

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 517-522

 

 

Automated measurements of junction characteristics to evaluate
parameters for semiconductor diodes

 

P K Patel, V A Kheraj, C J Panchal*, M S Desai, P D Vakil & K J Patel

Applied Physics Department, Faculty of Technology and Engineering, M S University of Baroda, Vadodara 390 001

*E-mail: cjpanchal_msu@yahoo.com

Received 29 December 2008; accepted 14 May 2009

Using National Instrument’s LabVIEW (Laboratory Virtual Instrument Engineering Workbench), a graphical programming language, we have measured the junction characteristics of different diodes in the temperature range 273-373 K. The PCI-6024E Data Acquisition Board and BNC-2120 for the acquisition of the data have been used. LabVIEW’s Controls and Functions enable one to control the experiment, measure the parameters, analyze and process the data. Ideality factor h, reverse saturation current I0, and material constant B have been evaluated using I-V characteristics. The barrier height FB and the band-gap energy EG, have been measured and compared using both I-V and C-V characteristics. For Schottky diode, the series resistance RS, and FB can be calculated using the Norde method. The band-gap energy has been measured using constant current source. Here, we have characterized p-n junction diodes viz. 1N5402, 1N5408, 1N4148, and 6A4. In addition, LabVIEW may be used to characterize other junction diodes like zener diode, LED, varactor diode, Schottky diode, etc.

Keywords: Semiconductor diode junction characteristics, LabVIEW automation

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 523-526

 

 

Hot electron scattering rates via LO-phonon emission in
two-dimensional GaAs1-xNx

 

Ankur Pandya#, Satyam Shinde# & Prafulla K Jha$

#Institute of Technology, Nirma University, S G Highway, Ahmedabad 382 481

$Department of Physics, Bhavnagar University, Bhavnagar, Gujarat 364 022

Email: ankur_msub@yahoo.co.in

Received 11 July 2008 ; revised 9 January 2009; accepted 29 May 2009

The carrier energy loss rate is studied under low and high electric fields at low temperature with the help of electron-phonon interactions via deformation potential coupling mechanism for two dimensional GaAs1-xNx. We observed that at low temperatures, the energy relaxation rate decreases with high electric fields but increases with nitrogen concentration. The electron energy loss rate decreases with nitrogen concentrations at low temperatures. The electron energy loss rate is found to be negative up to certain electric field due to phonon absorption and beyond that, there is phonon emission. The electron drift velocity increases with field but deceases with nitrogen concentration.

Keywords: Hot electron, Phonons interaction, Diluted nitride semiconductor, LO phonons

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 527-529

 

 

Forced oscillator model for entropic potential in the context of superconductivity

 

Z Bousnane* & M Benslama

*Physics Department, Faculty of Science, University of Batna, 05000 Algeria

Electromagnetism and Telecommunication Laboratory, Electronics Department, Faculty of Engineering
University of Constantine, 25000 Algeria

Email:bousnan@yahoo.fr

Received 11 August 2008; revised 6 January 2009; accepted 12 March 2009

The wave function chosen to establish the superconductivity seems to behave as an order parameter at T=Tc. Hereafter, the research of the cooled and cooling depth penetration allows us to obtain the differential equation governing the entropic potential. As similar to the law of the forced macroscopic oscillator, the plurality of the derivative extremums concerning the entropic potential with regard to the quadratic product of the energy, will lead to the matrix nature of the entropy after the centesimal zero. Such differential equation implies that the reduced entropy components will appear as eigen frequencies of the entropic potential. The macroscopic oscillator concept is introduced to express that the distance between the energy levels, will be decomposed univocally on an extremal length scale and multi locally as an inner length scale.

Keywords: Entropic potential, Macroscopic oscillator, Reduced grandeur, Second order action quantum, Order parameter

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 530-534

 

 

Electrical and optical properties of azo dye

 

M S Aziz 1 & H M El-Mallah2

1Physics Department, Faculty of Science, Mansoura University, Damitta, Egypt

2Department of Physics and Mathematical Engineering, Faculty of Engineering, Suez Canal University, Port-Said, Egypt

E-mail: azizm2000@Yahoo.com; hanaaelmallah53@hotmail.com

Received, 19 December 2008; revised 3 March 2009; accepted 5 June 2009

The electrical and optical properties of azo dye (1-phenylazo-2-naphthol) have been investigated. It has been found that the ac conductivity σac(ω) depends on the temperature and frequency. The ac conductivity as a function of frequency has been described by a power law with the frequency exponent s. The obtained values of s > 1 increase with increasing temperature up to T <373 K and then slightly decrease. The results obtained have been described by the nearly constant loss (NCL) behaviour. The dielectric constant ε and dielectric loss ε˘ depend on the temperature below elastic temperature Te and frequency F > 30 kHz and is nearly constant beyond. Both frequency and temperature dependence of the dielectric constant ε' and dielectric loss ε˘ have been attributed to interfacial and orientational polarization, respectively. The optical constants such as refractive index n, the dispersion energy Ed, the oscillation energy Eo, the room temperature optical dielectric constant ЄL, the high frequency dielectric constant at infinite wavelength Є and the ratio of carrier concentration to the effective mass N/m* have been determined using optical spectra. The spectra of refractive index n, exhibit two peaks and two shoulders at energies 1.455, 2.313, 2.731 and 2.385 eV, respectively.

Keywords: Azo dye, Electrical properties, Optical properties

 

 

Indian Journal of Pure & Applied Physics

Vol. 47, July 2009, pp. 535-537

 

 

Current-mode biquad employing single CDTA

 

D Biolek, V Biolkova & Z Kolka

Departments of EE & Radioelectronics, UD &  BUT, Brno, Czech Republic

E-mail: dalibor.biolek@unob.cz

Received 4 March 2008 ; accepted 9 January 2009

This paper presents a novel current-mode (CM) second-order filter, employing one current-differencing transconductance amplifier (CDTA), two grounded capacitors and one virtually grounded resistor. The filter provides two current outputs of lowpass (LP) and bandpass (BP) types for driving independent loads and one high pass (HP) current output, flowing through one of working capacitors. The results of the PSpice simulation, which utilizes the CDTA model on the level of CMOS transistor structure, are enclosed.

Keywords: CDTA, PSpice, Current-mode filters