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Indian Journal of Pure and Applied Physics
___________________________________________________________________________________
VOLUME 40
NUMBER 2
FEBRUARY 2002
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CONTENTS
Nuclear Physics
Theoretical prediction of magnetic octupole strength and form factor in rare earth nuclei using two rotor
79
model
A M Hegazi
Atomic and Molecular Physics
Vibrational studies of gel grown antimony thiourea chloride and bismuth thiourea chloride crystals
85
A Jayarama, S Govinda Bhat & S M Dharmaprakash*
Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics and Fluid Dynamics
89
Absorption, excitation and emission spectra of direct yellow 8 in aqueous solutions
R M P Jaiswal*, N Singh, Neena Jaggi & Manoj Gir
Condensed Matter: Structure, Mechanical and Thermal Properties
95
Effect of basic temperature gradients on Marangoni convection in ferromagnetic fluids
N Rudraiah*, I S Shivakumara & C E Nanjundappa
Study of influence of pre-heat treatment on thermoluminescence glow curve pattern and related trapping
parameters of technologically important synthetic quartz specimen
107
Y D Kale, Y H Gandhi* & T R Joshi
Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Application of light scattering for the determination of molecular parameters: Polystyrene balls
Ritesh Kumar Dubey, R K Pandey & D N Tripathi*
Flourescence studies of biphenyl doped by pyrene and perylene
S R Pujari*, S A Jadhav, P N Bhosale, P M R Rao & S R Patil
Structural and optical properties of monolithic silica-gel glasses containing Nd+3 using two different
precursors TEOS and TMOS prepared by sol-gel technique
I K Battisha
Development of fibre optic pH meter based on colorimetric principle
A L Chuadhari & A D Shaligram*
Interdisciplinary Physics and Related Areas of Science and Technology
111
Measurement of half-life of iridium-192 (HDR brachytherapy) by clinical dosimeters
Alok Kumar* & Sudama Singh
Geophysics, Astronomy and Astrophysics
137
Study of electric field, Aitken nuclei, gaseous concentrations and ionic conditions in contrasting
environment
S S Kandalgaonkar*, M I R Tinmaker, M K Kulkarni & Asha Nath
____________
*The corresponding author has been indicated by (*) mark in case of papers with more than one author
141
115
122
132
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 79-84
Theoretical prediction of magnetic octupole strength and form factor
in rare earth nuclei using two rotor model
A M Hegazi
Collective magnetic octupole transitions for the J =3+ member of the low lying K =1+band are investigated in the
framework of the two-rotor-model. The systematic study, carried out for deformed nuclei within a large range of the
deformation parameter. The form factor of the orbital collective M3 transitions has also been calculated in plane wave Born
approximation using Fermi density distribution. The theoretical calculations are simple and can be easily computed
numerically.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 85-88
Vibrational studies of gel grown antimony thiourea chloride and
bismuth thiourea chloride crystals
A Jayarama , S Govinda Bhat & S M Dharmaprakash
Single crystals of antimony thiourea chloride (ATC) and bismuth thiourea chloride (BTC) have been grown in gels at
ambient temperature using a controlled chemical reaction method. The laser Raman and FTIR spectra of the gel grown
ATC and BTC crystals have been recorded. The presence of thiourea ion, water molecules and normal mode vibrational
frequencies are identified and discussed. The basic ideas regarding the normal modes of vibration, selection rules for
Raman and IR spectra and hydrogen-bonding effect are considered in brief. Molecules of water of crystallization are
weakly bonded in antimony thiourea chloride crystal and do not take part in hydrogen bond formation.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 89-94
Absorption, excitation and emission spectra of
direct yellow 8 in aqueous solutions
R M P Jaiswal, N Singh, Neena Jaggi* & Manoj Gir
The absorption, excitation and emission spectra of direct yellow 8 [C 24H19N4NaO5S2] have been recorded in aqueous
solutions of concentrations between 10-4 and 10-6 Ml-1. This has led to the determination of optimum concentrations for the
absorption and emission spectra of the compound. Three absorption peaks at  ~ 395, 287 and 226 nm at the concentration
10-5 Ml-1 have been observed and assigned to 1W  1A (* n), 1Lb  1A (secondary *  ) and 1La  1A (primary
* ) transitions respectively. Emission spectra of the compound have shown fluorescence at 572, 442 and 345 nm.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 95-106
Effect of basic temperature gradients on
Marangoni convection in ferromagnetic fluids
N Rudraiah, I S Shivakumara & C E Nanjundappa
The effect of different basic temperature gradients on the onset of Marangoni ferroconvection is studied.
The resulting eigenvalue problem is solved by Galerkin technique for the lower boundary rigid and either
conducting or adiabatic and the upper boundary at which the surface tension acts is free adiabatic. The results
indicate that the stability of Marangoni ferroconvection is significantly affected by basic temperature gradients
and the mechanism for suppressing or augmenting the same is discussed in detail. It is found that, the results
obtained under the limiting conditions compare well with the existing ones.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 107-110
Study of influence of pre-heat treatment on thermoluminescence glow
curve pattern and related trapping parameters of technologically
important synthetic quartz specimen
Y D Kale, Y H Gandhi & T R Joshi
The observed thermoluminescence(TL) glow curve patterns of laboratory grown synthetic quartz have been plotted as
glow peak intensity ratio of low temperature glow peak to that of high temperature glow peak against either duration or
temperature of pre-heat treatment. Systematic changes in this intensity ratio with the changes in pre-heat treatment
conditions are observed. The systematic shifting of TL glow peak position towards lower temperature side with the changes
in duration of pre-heat treatment has also been reported. The observed facts are explained on the premise of colour centres
involved and phase transformation of quartz specimens when pre-heat treated at high temperature. The interpretations are
well-supported by trapping level characterization also.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 111-114
Application of light scattering for the determination of molecular
parameters: Polystyrene balls
Ritesh Kumar Dubey, R K Pandey & D N Tripathi
Average molecular weight, radius of gyration and second virial coefficient have been determined for polystyrene balls
using the static laser light scattering method. Reported results are quite reasonable and therefore, could be used to estimate
other physical parameters for the sample.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 115-121
Fluorescence studies of biphenyl doped by pyrene and perylene
S R Pujari, S A Jadhav, P N Bhosale, P M R Rao a & S R Patil
Fluorescent biphenyl absorbing short wave UV radiation and emitting at long wave UV radiation has been used as a solid matrix
and its luminophors have been prepared by adding intentionally fluorescent pyrene and perylene impurities. From the
fluorescence spectra it is seen that the pyrene impurity shifts the UV fluorescence of biphenyl towards red. Pyrene doped
biphenyl emits in blue region at a wavelength of maximum emission 458 nm due to formation of exciplex. Incorporation of
perylene into bicomponent biphenyl-pyrene system gave tricomponent crystal systems emitting in green region of visible
spectrum. The fluorescence spectra of tricomponent biphenyl are broad structureless bands with maximum emission at 501 nm.
These emission bands are interpreted as arising due to exciplex formation between pyrene and perylene in biphenyl matrix.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 122-131
Structural and optical properties of monolithic silica-gel glasses
containing Nd+3 using two different precursors TEOS and TMOS
prepared by sol-gel technique
I K Battisha
The sol-gel process was applied for the preparation of neodymium (Nd 3+) containing silica gel. Two different
procedures have been studied using two different precursor materials (TMOS) and (TEOS), giving silica gel and silica
containing Nd3+ of type I and type II, respectively. The absorption edge was determined. The normal transmission was
measured using Fourier transform infrared spectrometer FTIR. Raman analysis and X-ray diffraction (XRD) were carried
out to determine the crystal structure of the prepared samples. The thermally treated sample microstructures were
investigated using scanning and transmission electron microscope. Microheterogeneities with amorphous nature are found
at lower temperature, where crystalline phase appeared at higher temperature. Also DTA and TGA characteristic techniques
were used. The photoluminescence PL measurements were carried out.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 132-136
Development of fiber optic pH meter based on colorimetric principle
A L Chaudhari & A D Shaligram
A fiber optic pH sensor, having construction of probe based on the colorimetric principle is described. The probe
consists of a bundle of fibers with the central fiber as receiving fiber and the outer ring of fibers as transmitting fibers. The
LED’s of different colours are used as source and photodiode as detector. The probe is tested with pH buffer solution
prepared by the usual method with universal indicator to get coloured solutions depending upon value of pH. The changes
in the vicinity of the sensitive tip cause a variation in attenuation of specific reflected visible radiation bands. Initial results
and performance specifications using externally added universal indicator are described.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 137-140
Measurement of half-life of iridium-192 (HDR brachytherapy)by
clinical dosimeters
Alok Kumar and Sudama Singh
Iridium-192 is a very common radioisotope, used in the treatment of the cancer patients worldwide. Usually the
treatment is performed by brachytherapy, with remote afterloader machine of high dose rate (HDR). Half-life of iridium192 varies from 73.83 to 74.2 days. In clinical practice, the calibration of iridium-192 is performed by clinical dosimeters.
The authors used clinical dosimeters of 0.6 cc graphite thimble chamber with calibration jig and a re-entrant/well-type
chamber to perform comprehensive measurements of half-life of iridium-192. There were six different iridium-192
radioisotopes taken one by one up to their clinical lifetime for measurement on routine basis. It was found that each
individual iridium-192 source has a single decay constant and half-life ranging from 73.81 to 73.84 days with a mean value
of 73.825 days. The standard deviation was found to be  0.0084.
Indian Journal of Pure & Applied Physics
Vol. 40, February 2002, pp. 141-148
Study of electric field, Aitken nuclei, gaseous concentrations and
ionic conditions in contrasting environment
S S Kandalgaonkar, M I R Tinmaker, M K Kulkarni & Asha Nath
Ground based observations of electric field, Aitken nuclei (AN) and concentration of trace gases in fair weather
conditions were made at four locations having different environmental status (oceanic, hill-top, semi-urban and industrial).
The effect of concentrations of Aitken nuclei and trace gases on atmospheric electric field at these locations was examined
and an attempt was made to obtain effective attachment coefficients and mean life time small ions at the locations. The
results showed that in clean and relatively less polluted regions the diurnal as well as monthly mean variation of fair
weather electric field was significantly (0.01%) correlated with Aitken nuclei concentration. An examination of gaseous
concentrations suggested that the electric field was observed to be adversely affected in the regions which were enriched
with the SO2 loading and the particulate matter from the industries. The values of attachment coefficients and mean life
time of small ions obtained in the present set of study revealed that environmental status is an important factor to affect the
air pollutants which in turn affect the electrical parameters.