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Analysis of 226Ra, 232Th and 40K in soil samples for the assessment of the average effective dose
No full textThe activity concentrations of the natural radionuclides namely 238Ra, 232Th and 40K are measured
for soil samples collected from different locations of Faridkot and Mansa districts of Punjab. HPGe detector,
based on high-resolution gamma spectrometry system is used for the measurement of activity concentration.
The range of activity concentrations of 226Ra, 232Th and 40K in the soil from the studied areas varies from 21.42
Bq kg–1 to 40.23 Bq kg–1 , 61.01 Bq kg–1 to 142.34 Bq kg–1 and 227.11 Bq kg–1 to 357.13 Bq kg–1 with overall mean
values of 27.17 Bq kg–1, 95.22 Bq kg–1 and 312.76 Bq kg–1, respectively. Radium equivalent activities are
calculated for the analyzed samples to assess the radiation hazards arising due to the use of these soil samples
in the construction of dwellings. The absorbed dose rate calculated from activity concentration of 226Ra, 232Th
and 40K ranges between 9.87 and 18.55, 38.01 and 88.68 and 9.40 and 14.79 nGy h–1, respectively. The total
absorbed dose in the study area ranges from 61.10 nGy h–1 to 112.86 nGy h–1 with an average value of 84.80
nGy h–1. The calculated values of external hazard index (Hex) for the soil samples of the study area range from
0.36 to 0.68. Since these values are lower than unity, according to the Radiation Protection 112 (European
Commission, 1999) report, soil from these regions is safe and can be used as construction material without
posing any significant radiological threat to population. The corresponding average annual effective dose for
indoor and outdoor measured in the study area are 0.42 mSv and 0.10 mSv respectively.Author Affiliation: Rohit Mehra, Surinder Singh and Kulwant Singh
1.Department of Applied Sciences, Malout Institute of Management and Information Technology,
Malout-152 107, Punjab, India
2.Department of Physics, Guru Nanak Dev University, Amritsar-143 005,
Punjab, India
E-mail : [email protected] of Applied Sciences, Malout Institute of Management and Information Technology,
Malout-152 107, Punjab, India
Department of Physics, Guru Nanak Dev University, Amritsar-143 005,
Punjab, Indi
Uranium analysis in some food samples collected from Bathinda area of Punjab, India
No full textTo strengthen the radiation protection infrastructure in Bathinda, the uranium concentration in
daily diet of the residents has been measured and its associated radiation risks were estimated for the adult
population. Food samples were collected from major cancer prone areas of the district, from which daily diets
were prepared. These diet samples were analyzed using fission track technique. The measured values of the
uranium content were found to vary from 0.38 mBq/g in mustard seeds to 4.60 mBq/g in wheat. In case of milk
the uranium content is found to vary from 28.57–213.36 mBq/ with mean concentration of 61.35 mBq/ . This
leads to a daily dietary intake of 0.90 Bq/day. The measured value of 0.90 Bq d–1, contributes to 1.12 mSv to the
cumulative effective dose to the population. This dose is much large than the International Commission for
Radiological Protection (ICRP) annual effective dose limit of 1 mSv for the general public [1]. Therefore, it would
pose significant health hazard.Mukesh Kumar1*, Sangeeta Prasher2 and Surinder Singh3
1Department of Applied Science, RIMT-Institute of Engineering and Technology,
Mandi Gobindgarh-147 301, Punjab, India
2Department of Physics, Kanya Maha Vidyalaya, Vidyalaya Marg,
Jallandhar-144 004, Punjab, India
3Department of Physics, Guru Nanak Dev University, Amritsar-143 005, Punjab, India
E-mail : [email protected] of Applied Science, RIMT-Institute of Engineering and Technology,
Mandi Gobindgarh-147 301, Punjab, India
Department of Physics, Kanya Maha Vidyalaya, Vidyalaya Marg,
Jallandhar-144 004, Punjab, India
Department of Physics, Guru Nanak Dev University, Amritsar-143 005, Punjab, Indi
Intergranular percolation in granular YBCO/BaTiO3 composites
No full textFerroelectrics and high temperature superconductors are two promising materials for future electronic devices. Both being perovskite ceramic structures with similar crystal chemistry a set of samples were prepared from the composite of (1-x)YBa2Cu307–δ – (x)BaTiO3 (YBCO/BT). These samples were investigated with temperature dependent resistance, FTIR, X-ray diffraction and SEM-EDX analysis. It has been found that the critical exponent in the Tc0 (R = 0) region is in agreement with the percolation theory. A long-range superconducting order results from thermally assisted percolation process through weak-links between the grains. The connectivity in the coherent transition region can be explained by a power law.Annapurna Mohanta1, Dhrubananda Behera1*, Simanchalo Panigrahi1
and
Naresh Chandra Mishra2
1Department of Physics, National Institute of Technology, Rourkela-769 008, Orissa, India
2Department of Physics, Utkal University, Bhubaneswar-751 004, Orissa, India
E-mail : [email protected] of Physics, National Institute of Technology, Rourkela-769 008, Orissa, India
Department of Physics, Utkal University, Bhubaneswar-751 004, Orissa, Indi
Ferroelectric relaxor behaviour in Pb(Fe0.5Ta0.5)O3
No full textThe relaxor ferroelectric lead iron tantalate, Pb(Fe0.5Ta0.5)O3 (PFT) is synthesized by Coulombite
precursor method. The X-ray diffraction pattern of the sample at room temperature shows a cubic phase. The
field dependence of dielectric response is measured in a frequency range 0.1 kHz – 1 MHz and in a temperature
range from 173–373 K. The temperature dependence of permittivity (ε ′) shows broad maxima at various
frequencies. The frequency dependence of the permittivity maximum temperature (Tm) has been modelled using
Vogel-Fulcher relation.Ferroelectric relaxor behaviour in Pb(Fe0.5Ta0.5)O3
Chandrahas Bharti*, S N Choudhary and T P Sinha1
University Department of Physics, T M Bhagalpur University, Bhagalpur-812 007,
Bihar, India
1Department of Physics, Bose Institute, 93/1, A P C Road, Kolkata-700 009, India
E-mail : [email protected] Department of Physics, T M Bhagalpur University, Bhagalpur-812 007,
Bihar, India
1Department of Physics, Bose Institute, 93/1, A P C Road, Kolkata-700 009, Indi
Emission analysis of RE3+ (Eu3+, Tb3+ & Ho3+) : B2O3–BaOLiF/AIF3 glasses
No full textWe report here the luminescence spectra of certain rare earth ions (Eu3+,
Tb3+ & Ho3+) doped B2O3-BaO-LiF/AiF3 based on the measurements of emission and decay
curves of prominent emission transitions. For both the reference host glasses, FTIR,
XRD, DTA-TG profiles have been recorded to understand their structural and thermal
properties. Eu3+ doped glasses have shown five emission transitions of 5D0
. 7F01,2,3 & 4 located at 580nm, 593nm, 615nm, 655nm and 704nm respectively with an
excitation at .exci = 392 nm (7F0 . 5L6). Also under an UV source, these europium
glasses have displayed a bright red emission from their surfaces. Tb3+ glasses have
exhibited four emission bands of 5D4 . 7F6,5,4,3 at 491nm, 547nm, 588nm and 625nm
respectively with an excitation at .exci = 376 nm (7F6 . 5G6). Intense green
emission from the glass surfaces has been noticed upon exposure to the UV source.
Prominently bluish-green emission has been noticed from the surfaces of the holmium
glasses under an UV source and same emission transition (5F4 . 5I8) at 519 nm with
an excitation at .exci
= 389 nm (5I8 – 5G4) has also been obtained from their measured emission spectra.
For all the prominent emissions of the rare earth glasses, decay curves have been
measured to compute their lifetimes.Emission analysis of RE3+ (Eu3+, Tb3+ & Ho3+) : B2O3–BaOLiF/AIF3 glasses
B H Rudramadevi and S Buddhudu*
Department of Physics, Sri Venkateswara University, Tirupati-517 502,
Andhra Pradesh, India
E-mail : [email protected] of Physics, Sri Venkateswara University, Tirupati-517 502,
Andhra Pradesh, Indi
The layer disorders defect in coir fiber under thermal and chemical treatment
No full textNatural coir fibers, subjectd to thermal treatments in the range of 0oC
to 200oC and alkali treatment with 5% to 30% concentration w/w, have been used in
the present investigation to determine the interlayer variability of the cellulose
planes (020), (110) and (110). Among the equatorial reflections (110), (110) and
(020), the extent of variability is found to be more with the proportion of such
affected planes less for (020) reflection in the native cellulose at lower
temperature while at higher temperature (110) and (110) become more affected by
variability defect. (110) and (1 10) planes are more affected also with alkali
treatment.The layer disorders defect in coir fiber under thermal and chemical treatment
D N Mahato*, B K Mathur and S Bhattacharjee
Department of Physics, Indian Institute of Technology,
Kharagpur-721 302, West Bengal, India
E-mail : [email protected] of Physics, Indian Institute of Technology,
Kharagpur-721 302, West Bengal, Indi
Effect of enhancement of selenium content in zirconium sulphoselenide on its photoelectrochemical behaviour
No full textIn this paper, we have attempted to fabricate PEC solar cells with mixed
crystals of Zirconium sulphoselenide. Energy band location and redox analysis of the
material have been made using Mott-Schottky plots. These studies justify the
selection of an appropriate electrolyte for PEC work. Various solar cells fabricated
with single crystals of selenium rich and selenium deficient zirconium
sulphoselenide have been prepared. The solar cell parameters e.g. the fill factor
(FF), open circuit voltage (Voc), short circuit current (Isc) and efficiency (.) for
all the different cells have been determined. In order to see the effect of
enhancement of selenium in ZrS on photoresponse, the electrolyte and intensity of
illumination were kept constant and all the electrodes
xSe2-x
were prepared from crystals showing absolutely plane faces obtained through the act
of cleavage with the help of an adhesive tape. The results have been thoroughly
analysed and the implications have been discussed.Effect of enhancement of selenium content in zirconium sulphoselenide on its
photoelectrochemical behaviour
G K Solanki*, Sudeep Goyal, S K Arora, Dipika B Patel and M K Agarwal
Department of Physics, Sardar Patel University,
Vallabh Vidyanagar-388 120, Gujarat, India
E-mail : [email protected] of Physics, Sardar Patel University,
Vallabh Vidyanagar-388 120, Gujarat, Indi
Effect of cobalt substitution on microstructure and magnetic properties in ZnO nanoparticles
No full textFerromagentic semiconductors have been actively pursued because of their potential as spin
polarized carrier sources and easy integration into semiconductor technology. One such material, ZnO has been
shown to be a potential Diluted Magnetic Semiconductor (DMS). The appearance of ferromagnetism, however,
is found to be sensitive to the processing conditions. We report synthesis of ZnO nanoparticles of size ~20 nm
by a simple co-precipitation technique using metal nitrates and NaOH as precipitant. The particles are selforganised
and reveal single crystalline behaviour in electron diffraction pattern. Incorporation of Co in ZnO matrix
leads not only to the reduction in crystallite size but also to the modification of the structure. At 5% Co, the
particles are highly textured. The particles also aggregate and the aggregated mass have nearly rectangular
shape as seen through TEM. Increasing Co to 10%, results into further reduction of particle size and the particles
self organize in a line, which looks like nanofibers. This alignment of particles increases by increasing the Co
content further. This type of growth of nanofibers above Co ≥ 10% is well correlated with the anisotropic peak
broadening observed in the XRD spectra. In addition, Co substitute Zn site up to 20% without showing any extra
phase in XRD spectra as compared to 7 to 10% in case of bulk. Transport and magnetic studies indicate that
conductivity increases with increasing Co content, but carrier mediated ferromagnetism is absent down to 10 K.Effect of cobalt substitution on microstructure and magnetic properties in ZnO
nanoparticles
Chandana Rath1*, Sonal Singh1, P Mallick2, D Pandey1, N P Lalla3 and N C Mishra4
1School of Materials Science & Technology, Institute of Technology, Banaras Hindu
University, Varanasi-221 005,
Uttar Pradesh, India
2Department of Physics, North Orissa University, Baripada-757 003, Orissa, India
3UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore-452 017, Madhya
Pradesh, India
4Department of Physics, Utkal University, Bhubaneswar-751 004, Orissa, India
E-mail : chandanarath@yahoo. com1. School of Materials Science & Technology, Institute of Technology, Banaras Hindu
University, Varanasi-221 005,
Uttar Pradesh, India
2. Department of Physics, North Orissa University, Baripada-757 003, Orissa, India
3. UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore-452 017, Madhya
Pradesh, India
4. Department of Physics, Utkal University, Bhubaneswar-751 004, Orissa, Indi
Study of acoustic parameters of binary mixtures of a nonpolar liquid with polar liquid at different frequencies
No full textThe densities (.) and ultrasonic velocities (C) of binary mixture of
diisopropyl ether (DIPE) and bromobenzene (BB) have been measured at different
frequencies (1 MHz, 3 MHz and 5 MHz) over the entire range of mole fraction of
diisopropyl ether (DIPE) at temperature 303 K. The intermolecular free length (Lf),
isentropic compressibility (ß), acoustic impedance (Z) and excess values of
isentropic compressibility (ßE) and acoustic impedance (ZE) have been computed using
values of ultrasonic velocity (C) and density (.).
The ultrasonic velocity, intermolecular free length are positive whereas the excess
values of isentropic compressibility and acoustic impedance are negative over the
entire composition range of DIPE which indicates presence of specific interactions
between unlike molecules. The results are discussed in the light of intermolecular
interactions occurring in the mixtures.
Keywords : Binary mixture, ultrasonic velocity, isentropic compressibility, acoustic
impedance, intermolecular free length.Study of acoustic parameters ofbinary mixtures of a nonpolar liquid with polar
liquid at different frequencies
G Nath*, S Sahu and R Paikaray
Department of Engg. Physics, Dhaneswar Rath Institute of Engg. and Management
Studies (D.R.I.E.M.S.),
Tangi, Cuttack-754 022, Orissa, India
Post Graduate Department of Physics, Ravenshaw University, Cuttack-753 001, Orissa,
India
E-mail : [email protected] of Engg. Physics, Dhaneswar Rath Institute of Engg. and Management
Studies (D.R.I.E.M.S.),
Tangi, Cuttack-754 022, Orissa, India
Post Graduate Department of Physics, Ravenshaw University, Cuttack-753 001, Orissa,
Indi
Microstructural analysis of neutron-irradiation induced changes in polyester fibre studied using EPMA
No full textElectron microscopy is an important characterization technique for the
study of textile fibre as it gives more information on fabric wear, nature of fibre
fracture, chemical degradation, abrasion, fatigue and many others. Electron Probe
Micro Analyzer (EPMA) micrographs of virgin and some neutron-irradiated samples
(graphite coated) are discussed. The filament diameter, D, of virgin PET fibre
obtained from EPMA study was 12.5 µn. The surface topography of single filament
distinctly reveals the core and sheath parts of the filament. The core diameter of
the virgin fibre was estimated to be 1.43 µm. The fibre irradiated at fluence 1 ×
1012 n/cm2 shows radiation induced sphere like polymer balls or spherulites of
diameter 2.27 µm in the expanded core region. Due to irradiation, the sheath area
crosslinks with expanded core region, which may be responsible for increase of
strength and hardness of the polymer materials. Moreover, the micrograph at 3000 X
magnifications clearly shows that there is no preferred orientation of the polymer
in any direction confirming the isotropic nature of the sample.Microstructural analysis of neutron-irradiation induced changes in polyester fibre
studied using EPMA
Biswajit Mallick1*, Ramesh Chandra Behera2, Simanchal Panigrahi1, Tanmaya Badapanda1,
Biswanath Parija1, Banita Behera1, Manas Panigrahi1 and Madhumita Sarangi2
1Department of Physics, National Institute of Technology, Rourkela-769 008, Orissa,
India
2Department of Metallurgical and Materials Engineering, National Institute of
Technology,
Rourkela-769 008, Orissa, India
E-mail : [email protected] of Physics, National Institute of Technology, Rourkela-769 008, Orissa,
India
2Department of Metallurgical and Materials Engineering, National Institute of
Technology,
Rourkela-769 008, Orissa, Indi