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Indian Journal of Pure and Applied Physics

 

 

 

ISSN: 0019-5596

CODEN: IJOPAU 42 (12) 867-958

Volume 42

Number 12

DECEMBER  2004

 

 

CONTENTS

 

Nuclear Physics

 

Aerosol test facility for fast reactor safety studies

R Baskaran*, T S Selvakumaran & V Subramanian

 

873

Absorbed dose distribution at a large scale gamma irradiator – A data analysis

P G Benny, M R Shah, B C Bhatt & S Sabharwal*

879

Atomic and Molecular Physics

 

fluorescence quenching spectra of p-chloranilne and p-toluidine

S Bakkialakshmi*, B Shanthi, R Santhi & D Chandrakala

937

Computerized glow curve deconvolution on thermoluminescence of Cu-doped borate glass

S Nabadwip Singh*, B Arunkumar Sharma, R K Gartia & A Nabachandra Singh

886

Systematization of L X-ray satellites I: La satellites

U D Misra* & N Kumar

891

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

 

Indigenous development of a low cost high power 2kW(CW), 2.45GHz microwave system

S K Jain*, Akhilesh Jain & P R Hannurkar

896

Ultrasonic studies on aqueous ternary electrolytes

R Ezhil Pavai, P Vasantharani* & A N Kannappan

934

Polarization based imaging of sub- surface tissue

G F Sudha* & T G Palanivelu

902

Condensed Matter: Structural, Mechanical and Thermal Properties

 

Theoretical study of the effect of applied stress on the binding energy of a donor impurity in GaAs quantum well dot within an infinite potential barrier

H Odhiambo Oyoko*, C A Duque & N Porras-Montenegro

908

Synthesis and structural characterization of Bi2O3 – M2O3 (M=Dy and Pr) binary systems

Srikant Ekhelikar & G K Bichile*

912

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

 

Study of copper- silicon junctions fabricated by selective electroless deposition

Sunil Dhingra, Sanjiv Arora & P J George

916

Dielectric relaxation studies of binary mixtures of acetone and N-methylacetamide in benzene solution using microwave absorption data

Vir Singh Rangra & D R Sharma

921

Structural and electrical properties of nano-sized magnesium aluminate

Siby Kurien, Shajo Sebastian, Jose Mathew & K C George

926

Annual Author Index

945

Annual Keyword Index

950

List of Referees

956

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


 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 873-878

 

 Aerosol test facility for fast reactor safety studies

 R Baskaran, T S Selvakumaran & V Subramanian

 

An Aerosol Test Facility (ATF) has been designed, fabricated, assembled and tested for the fast reactor safety studies. ATF mainly consists of an aerosol chamber, a plasma torch for the production of aerosols of fuel and fission product equivalent materials, a sodium combustion cell for the production of sodium aerosols, aerosol measurement apparatus, and auxiliary systems such as water cooling, air flow, gas flow, pneumatic control, vacuum, and material handling systems. The systems involved in ATF are individually tested and integrated. In this paper, the details of various systems of ATF and the aerosol characteristics of coolant (sodium) and fission product (strontium) are described.

 

[Keywords: Aerosol test facility, Fast reactor safety, Plasma torch]

IPC Code: B21C 15/28, G21C 21/00

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 879-885

  

Absorbed dose distribution at a large scale gamma irradiator — A data analysis

P G Benny, M R Shah, B C Bhatt & S Sabharwal

 

Laboratory experiments on the sand samples separated from sludge have been carried out to study their uncertainty associated with dose response and calibration. The uniformity of absorbed dose in a batch of sludge in a large-scale liquid sludge gamma irradiator has been examined by using sand samples separated from sludge as an in-situ dosimeter. Statistical analysis of the data, by applying ANOVA test, has been used to evaluate uniformity of dose. The re-circulation time for irradiation of sewage sludge to a dose of 3 kGy for its disinfection has been optimized using the data obtained.

 

[Keywords: Gamma irradiator, Absorbed dose distribution]

IPC code: B01J 19/00

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 886-890

 

Computerized glow curve deconvolution on thermoluminescence of Cu-doped borate glass

 S Nabadwip Singh, B Arunkumar Sharma & R K Gartia and A Nabachandra Singh

 

Trapping parameters namely activation energy (E), frequency factor (s) and order of kinetics (b) of thermoluminescence (TL) curve of Cu-doped borate glass have been evaluated using Computerized Glow Curve Deconvolution (CGCD) technique. It is observed that near to temperature 108°C, a prominent peak of Cu-doped borate glass, after various extents of thermal cleaning, was observed obeying second order kinetics with an exponential distribution of traps of energies in the range (0.853 ~1.15) eV and frequency factors in the order of (1010~1011) s-1.

 

[Keywords: Thermoluminescence, Non-crystalline, Glow curve deconvolution ]

IPC Code: G06N 7/00

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 891-895

  

Systematization of L X-ray satellites I: La satellites 

U D Misra & N Kumar

 

The iterative procedure, based on Hagström's method of the doubly modified Moseley plot, has been used for the first time for the systematization of La X-ray satellites for 48 < Z < 80. This has resulted in: (i) the identification of a number of satellites measured by certain researchers and (ii) removal of anomalies in the measurements of the wavelength of some satellite lines.

 

[Keyword: La satellites, LX-ray satellites]

IPC Code: G01J 3/443

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp 896-901

 

Indigenous development of a low cost high power 2 kW (CW), 2.45 GHz microwave system

S K Jain*, Akhilesh Jain & P R Hannurkar

 

An indigenous low cost high power 2kW (CW), 2.45 GHz microwave system for Electron Cyclotron Resonance (ECR) proton source has been designed and developed using WR-284 waveguide sections. An ECR proton source (50 keV, 30 mA) is under development as an injector to Proton Synchrotron (PS) is being built at Centre for Advanced Technology (CAT), Indore. Using this microwave system the microwave power was delivered successfully to the plasma chamber and stabilized plasma was produced. The details of the design, fabrication and performance of the waveguide components are presented in this paper.

 

[Keywords: Electron cyclotron resonance; Microwave system; Waveguide component]

IPC code: H 01 J 9112

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 902-907

 

Polarization based imaging of sub-surface tissue

 G F Sudha* & T G Palanivelu

 

A method to image tissue phantoms using optical technology is demonstrated. The proposed method is based on polarization discrimination. This paper presents both experimental and Monte Carlo based simulation results for the backscattered images of a diffuse reflector object at varying depths illuminated by a linear polarized light beam. The numerical model is validated by experimental measurements using a tissue phantom consisting of 2.02 mm diameter polystyrene spheres suspended in deionised water. In this work, the problem related to scattering of light is solved by image-processing means. Results indicate that the proposed method improves the contrast of the subsurface tissue images up to a depth of 1 cm.

 

[Keyword: Subsurface tissue, Optical technology, Polarization]

IPC Code: A61N 5/073

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 908-911

  

Theoretical study of the effect of applied stress on the binding energy of a donor impurity in GaAs quantum well dot within an infinite potential barrier

H Odhiambo Oyoko, C A Duque & N Porras-Montenegro

 

A theoretical study has been carried out on the effect of applied stress on the binding energy of a shallow monovalent donor impurity in a GaAs quantum well dot (QWD) of square cross-section. In our calculations, a variational technique [Csavinzky & Oyoko, Phys Rev B, 43 (1991) 9262.] within the effective mass approximation has been used. In our model the donor impurity is confined to the QWD by an infinite barrier potential unlike in a previous study [Oyoko et al. J Appl Phys, 90 (2001) 819.] where the barrier potential was finite. The donor impurity was located at various positions along the axis (Z-direction) of the QWD. The stress was applied along the same axis. The results show that for constant QWD dimensions Lx, Ly and Lz, for various donor positions, the binding energy increases with the applied stress as the donor position varies from on-edge to on-center locations. The binding energy is also found to increase as the QWD length decreases in both cases of on-edge and on-center donor locations for constant Lx and Ly as well as for decreasing QWD size. In all the cases considered, the binding energy is much larger for the on-center than for the on-edge positions for the same QWD dimensions and the same applied axial stress. The results obtained show that in experimental study of optical and electronic properties of such nanostructures as QWDs, the effect of stress on donor impurity binding energies should be taken into consideration.

 

[Keywords: Binding energy, Donor impurity, GaAs quantum well dot, Infinite potential barrier]

IPC Code: G01L

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 912-915

 

 

Synthesis and structural characterization of Bi2O3-M2O3 (M=Dy and Pr) binary systems

 Srikant Ekhelikar & G K Bichile

 

The binary systems Bi2O3-Dy2O3 and Bi2O3-Pr2O3 have been investigated by doping Dy2O3 and Pr2O3 in the composition range 10 - 40 mole % prepared by ceramic method. From the phase evolution studies of Dy2O3 doped samples, it was observed that fluorite structured f c c phase is stabilized for the composition range 10-40 mole %. The stability of d- phase was affected by the heat treatment temperatures. The higher the content of dopant concentration, the higher was the sintering temperature. The lattice parameter for Dy2O3 doped samples decreased with the increase of dopant concentration and obeyed Vegard’s rule. From the structural studies of Pr2O3 doped samples rhombohedral phase was found for 10 to 30 mole % of dopant concentrations. For 40 mole % of dopant concentration, the impurity peaks were observed in the XRD patterns along with rhombohedral phase. The unit cell parameters for Pr2O3 doped samples were evaluated on hexagonal settings.

 

[Keywords: Solid electrolytes, Binary solid solutions, X-ray diffraction, Lattice parameter]

IPC Code: C25B 1/00

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 916-920

 

 

 Study of copper-silicon junctions fabricated by selective electroless deposition

 Sunil Dhingra, Sanjiv Arora & P J George

 

The metal semiconductor contacts have been fabricated by electroless deposition of copper on chemically cleaned p-type silicon and their characteristics studied. A continuous thin film of good quality and adhesion is formed. The values of barrier height and the ideality factor are found to be comparable to those of vacuum evaporated contacts. The barrier heights measured from I-V and C-V characteristics are also found to be comparable.

 

[Keywords: Copper-silicon junctions, Electroless deposition, Metal semiconductor]

IPC Code: H01L

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 921-925

 

 

Dielectric relaxation studies of binary mixtures of acetone and N-methylacetamide in benzene solution using microwave absorption data

Vir Singh Rangra & D R Sharma

 

The dielectric relaxation times(t) and the dipole moments(m) of the binary mixtures of different molar concentrations of acetone(CH3COCH3) in the binary mixtures of acetone and N-methylacetamide(NMA) in benzene solutions have been calculated by using standard standing wave microwave techniques and Gopala Krishna’s single frequency(9.88GHz) concentration variational method at different temperatures (25, 30, 35, 40°C).The dielectric relaxation process has been found to be an activated process. The energy parameters (DHe, DFe, DSe) for the dielectric relaxation process of binary mixtures containing 30% mole-fraction of acetone have been calculated at the respective given temperatures and the comparison has been made with the corresponding energy parameters (DHh, DFh, DSh) for the viscous flow. On the basis of the observations, it is found that the dielectric relaxation process can be treated as the rate process like the viscous flow process. The solute-solute and solute-solvent molecular associations have been predicted.

 

[Keywords: Dielectric relaxation, Binary mixtures, Acetone, N-methylacetamide]

IPC Code: G 01R 27/00

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp.926-933

 

 

Structural and electrical properties of nano-sized magnesium aluminate

 Siby Kurien, Shajo Sebastian, Jose Mathew & K C George*

 

The effects of temperature, frequency, and molarity on the dielectric behaviour and ac electrical conductivity have been studied for nanosized samples of MgAl2O4 prepared by chemical co-precipitation technique. X-ray powder diffraction (XRD) study shows that the particle size is 8 nm and the system is orthorhombic. FTIR studies have been used to confirm the formation of the resultant compound. The variations of dielectric constant (΢), the loss tangent (tand) as a function of frequency (200 Hz – 4 MHz) and the temperature (303-450 K) have also been studied. The experimental results indicate that the real dielectric constant (΢), tand, and logs increase with temperature and then decrease. The dielectric constant (΢), and tand, decrease while the ac conductivity (sac) increases as the frequency increases.

 

[Keywords: Nanosized magnesium aluminate, Electrical conductivity, Molarity]

IPC Code: B82B

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 934-936

 

 

Ultrasonic studies on aqueous ternary electrolytes

 R Ezhil Pavai, P Vasantharani & A N Kannappan

 

The density, viscosity and ultrasonic velocity have been measured in two ternary electrolytic mixtures of sodium chloride and manganese chloride in the aqueous mixture of magnesium sulphate and cadmium chloride at 308, 313 and 318 K. From these values the parameters like free volume, internal pressure, solvation number and viscosity B-coefficient have been calculated. The results are interpreted on the basis of ion-ion, ion-solvent and structure making/promoting tendency of the electrolytes.

 

[Keywords: Free volume, Internal pressure, Solvation number, Viscosity B-coefficient]

IPC Code: G01H

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 42, December 2004, pp. 937-939

 

 

Fluorescence quenching spectra of p-chloranilne and p-toluidine

S Bakkialakshmi, B Shanthi*, R Santhi & D Chandrakala

 

The fluorescence quenching spectra of p-chloraniline, using nitrobenzene and acetonitrile as quenchers in ethanol and p-toluidine, using benzoic acid and carbon tetrachloride as quenchers in chloroform have been obtained. The stern-volmer constants for all quenching process have been plotted. The regression analysis for stern-volmer plot has been carried out. Regression coefficient (r) and the stern-volmer constant (Ksv) were calculated. The stoke’s shift, ionization potential, electron affinity and the solvent parameter (z) have also been calculated.

 

[Keywords:           Fluorescence quenching, Nitrobenzene, Acetonitrile, p-chloraniline, Benzoic acid, Carbon tetrachloride, p-toluidine, Stern-volmer plot, Stoke’s shift, Ionization potential, Electron affinity, Solvent parameter]

IPC Code: G01J 3/00