013883   Ikeda M (NO, Musashi Univ, Nerima-ku, Toyotamakami 1-26-1, Tokyo 176-8534, Japan, Email: ikeda@cc.musashi.ac.jp) : Estimate of kinetic energy maxima of cyclotron-resonant electrons interacting with whistler mode waves. Indian J Radio Space Phys 2012, 41(6), 579-93.

Active experiments to probe hot plasma in the magnetosphere were conducted at Siple Station, Antarctica. The multistations measurements of VLF Siple signals on the ground were also conducted in Canada. The results from the Siple active experiments at L=5.1, the relativistic treatments, and the results obtained from the multi-stations measurements at L=4.1 showed almost similar results. The relativistic treatment of separatrix at L=5.1 theoretically indicates the total energy of trapped electron, which was estimated to be 0.315 to 16 keV (at maximum of K_⊥) by estimates of parallel resonance velocity and wave magnetic field amplitude of 11 PT, and the effective instability depending on the weak relativistic electrons with kinetic energy 10.9 keV in the perfect resonance condition. The kinetic energy 10.9 keV is almost coincident with some results of Sonwalkar et al. [Properties of the magnetospheric hot plasma distribution deduced from whistler mode wave injection at 2400 Hz: Ground-based detection of azimuthal structure in magnetospheric hot plasmas, J Geophys Res (USA), 102(1997) 14363].

14 illus, 44 ref

013882   Buliya A (Physics Dep, Mewar Univ, Gangrar, Chittorgarh, Rajasthan, Email: asha_buliya@yahoo.com) : Complex dielectric permittivity of salt affected soil at lower microwave frequancies. Indian J scient Res 2012, 3(2), 127-30.

The Real and Imaginary parts (ε' & ε") of the Complex Dielectric Permittivity (ε*) of Loamy sand soil with varied salinity levels have been determined experimentally using a Vector Network Analyzer in the frequency range 150 MHz to 2.2 GHz. It has been observed that the effect of salinity in the soil is more pronounced in the dielectric loss as compared to dielectric constant. The Power reflection coefficient(R) and Emissivity(e) of Microwaves for the soil were also calculated from the measured value of complex dielectric permittivity. These parameters show expected variation with soil salinity and microwave frequencies used and have great importance in remote sensing of soil moisture using microwave signals.

2 illus, 1 table, 6 ref

010902   Xiao-Hong L;Rui-Zhou Z;Xian-Zhou Z (College of Physics and Engineering, Henan Science and Technology Univ, Luoyang-471 003, China, Email: lorna639@126.com) : Molecular structure, NBO analysis and vibrational spectra of 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine by ab-initio and density functional theory. Indian J pure appl Phys 2012, 50(10), 697-705.

Quantum chemical calculations have been performed to compute optimized molecular geometry, atomic charges and vibrational characteristics for 2-hydroxy-3-methoxy-N-(2-chloro-benzyl)-benzaldehyde-imine (C₁₅H₁₄O₂NCl) in the ground state using restricted Hartree-Fock (RHF) and density functional theory (DFT) methods with 6-31+G** basis set. NBO analysis is also performed. The IR and Raman spectra are obtained and assigned by vibrational analysis and found to be reliable compared with the experimental results. Theoretical vibrational spectra of the title compound have been interpreted by means of potential energies distributions (PEDs) using MOLVIB program. In addition, the results show that there exist C-H...N and O-H...O hydrogen bonds in the title compound, which play a major role in stabilizing the molecule and are confirmed by the natural bond orbital analysis. The Mulliken population analysis on atomic charges has also been calculated.

4 illus, 5 tables, 20 ref

010901   Wernli C;Hoedlmoser H;Boschung M;Hohmann E; Mayer S (Radiation Safety and Security Div, Paul Scherrer Institute, Villigen, Switzerland, Email: Christian.Wernli@psi.ch) : Neutron dosimetry around accelerators in Switzerland. Indian J pure appl Phys 2012, 50(11), 757-60.

The Radiation Safety and Security Division of the Paul Scherrer Institute (PSI) operates an accredited calibration lab for photon and neutron dosimeters and dose rate monitors as well as an approved dosimetry service for photon and neutron environmental and personal dosimeters. The reference neutron fields of the calibration lab are traceable to PTB in Germany and the irradiation conditions within the room have been studied by MCNPX simulation with and without the influence of the ISO water slab phantom. Passive dosimetry systems based on track etch methods are traditional at PSI. For highly sensitive area monitoring, a fission track detector within a moderator is used and for individual monitoring CR-39 detectors in various types of badges are in use. Readout of these detectors is performed by the older Autoscan instruments or by new types of TASL scanning systems. Optimization programs for etching conditions and readout procedures are ongoing. Besides internal use at PSI, the dosimetry group runs the individual neutron dosimetry service for CERN in Geneva and Desy in Hamburg and further external clients. In addition to the standard calibration based on reference radiation fields of a ²⁴¹Am-Be neutron source the active and passive neutron dosimetry systems are also calibrated in realistic neutron radiation fields around accelerators.

4 illus, 7 ref

010900   Vipin Dev; (Indus Operation & Accelerator Physics Design Div, RRCAT, Indore-452 013, Email: vipindev@rrcat.gov.in) : Radiation safety during the commissioning trials of synchrotron radiation beamlines of Indus-2. Indian J pure appl Phys 2012, 50(11), 808-10.

There are 26 synchrotron radiation beamlines planned to be installed in Indus-2 for various applications. 5 are commissioned, 2 are under commissioning trial stage and several are under installation. During operation of these beamlines, radiation levels are monitored within and outside hutches. During initial trial runs streaming of radiation to accessible areas through gaps in the hutch structure and overlaps was observed. Shield augmentation and reducing gap between overlaps are found to be effective in preventing streaming of radiation. The paper describes radiation safety features, surveillance program and radiation levels in and around synchrotron radiation beamlines hutches of Indus-2.

1 illus, 3 tables, 3 ref

010899   Verma D; (Heath Physics Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: dimple@rrcat.gov.in) : Residual radioactivity measurements at Indus accelerator complex. Indian J pure appl Phys 2012, 50(11), 825-8.

Indus-1 and Indus-2 are two Synchrotron Radiation Sources (SRS) operational at RRCAT, Indore. During shut down of these accelerators for maintenance purpose, residual radioactivity measurements were carried out. The present paper describes the measurements carried out and the radio-isotopes identified. Maximum dose rate due to induced activity obtained is 28 μSv/h near dipole-5 of booster synchrotron after 12 h of cooling time. In case of Indus-1 and Indus-2 SRS, the dose rate due to induced radioactivity is found to be of the order of 2-3 μSv/h. The radio isotopes identified at these beam loss locations are beta emitters that do not pose serious external hazard to the working personnel.

5 tables, 3 ref

010898   Tripathy S P;Verma D;Sunil C;Haridas G;sarkar P K (Accelerator Radiation Safety Section, Health Physics Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: sam.tripathy@gmail.com) : Measurement of high energy neutrons (E> 50 MeV) at electron accelerators of Indus accelerator complex using bismuth fission detectors. Indian J pure appl Phys 2012, 50(11), 843-6.

This paper reports the measurement of high energy neutron component (E <62> 50 MeV) carried out at the Indus-1 (450 MeV) and Indus-2 (2.5 GeV) electron accelerators (RRCAT, Indore, India). The study is based on the registration of neutron induced fission fragments from bismuth radiators in the adjoint solid polymeric track detectors. These bismuth fission detector (BFD) stacks are exposed at the injection septums of booster synchrotron, Indus-1 and Indus-2 storage rings, where the possibility of dose due to beam loss is expected to be maximum. The detection efficiency of BFD is enhanced by enlarging the detector surface area and accordingly a large area spark counter is fabricated for automatic and rapid counting of the track densities. The dose equivalent rates are found to be about 0.11 mSv/h at the booster synchrotron and the Indus-1 storage ring, and about 0.62-0.65 mSv/h at the Indus-2 storage ring.

4 illus, 14 ref

010897   Thennarasu J;Meenakshi G (NO, Sri Aravindar Engineering College, Villupuram) : Compatibility studies and evaluation of ultrasonic velocity and percentage deviation of ternary mixture of cyclohexane, toluene and 2-propanol at 303.15 k & 308.15 k.. J pure appl Ultrasonics 2011, 33(4), 88-91.

In recent years ultrasonic investigation of critical phenomena in ternary mixtures of liquids have been the subject of intensive research of both theoreticians and experimentalists. Particularly the Anomalous increase of Ultrasound attenuation near the critical region of ternary liquid mixtures has been widely studied. The experimental study of the above liquids have been carried out at 303.15 K & 308.15 K and the data can be described with its compatibility studies over a wide range of composition ranging from 0-100%. of above different liquids. The result of ultrasonic velocity and its derived percentage deviation have been used to discuss the statistical approach of the blend under study. These discussion revealed that the blend is weakly polar in an ideal mixing relation. Using this data, the interaction parameters of molecular radius (r_m), molar sound velocity (R_mix) and molar volume (V_mix) were computed. The ultrasonic velocity results are further confirmed by density and percentage deviation results. For the ternary mixtures, the observed results shows that the Nomoto method seems to give good results for the evaluation and compared to Van-Dael's method.

5 tables, 12 ref

010896   Thakur V M;Jain A;Biju K;Sunil C;Anilkumar S; Babu D A R;Sharma D N (Radiation Safety System Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: vmthakur@barc.gov.in) : Optimization of moderator thickness for BF₃ detectors used for monitoring of fissile material. Indian J pure appl Phys 2012, 50(11), 811-13.

Monitoring of fissile material content in waste drums requires an energy independent neutron response due to the inherent moderation of neutrons in the waste matrix. For this purpose, a detector assembly consisting of three BF₃ detectors each 100 cm long and covered with 3.7 cm thick HDPE moderators arranged in a linear geometry has been set-up. The response of the assembly as measured using different neutron sources was observed to be appropriate within acceptable limits. Response of the detector assembly to a ²⁵²Cf source which has a fission neutron spectrum similar to that of fissile materials was measured and compared with the FLUKA based simulations. The sensitivity of the system as evaluated using FLUKA simulations for a ²⁵²Cf neutron source was found to be in good agreement with the experimental values. This study indicates that the optimum range of moderator thickness for effective monitoring of fissile material using BF₃ neutron detector assembly is 6-7 cm.

4 illus, 3 ref

010895   Sukhdeep Singh;Rallhan N K;Kotnala R K;Verma K C (Chemistry Dep, Eternal Univ, Baru Sahib, Himachal Pradesh-173 101, Email: deepsukh.singh@gmail.com) : Nanosize dependent electrical and magnetic properties of NiFe₂O₄ ferrite. Indian J pure appl Phys 2012, 50(10), 739-43.

The effect of nanosize particles on dielectric and magnetic properties of NiFe₂O₄ (NF) ferrite has been studied. NF nanoferrites were prepared by a chemical combustion route followed by annealing temperatures from 400° to 700°C. The X-ray diffraction (XRD) shows minor amorphous behaviour of NF at 400°C. However, spinel ferrite structure has been observed with higher annealing in the temperature range 500-700°C. The average particles size is measured using Debye-Scherer's relation. The particle's size is also measured by transmission electron microscopy and the average value is at nm scale. Room temperature dielectric properties viz.; dielectric constant (ε) and loss (tan5) for all the specimens have been studied as a function of applied frequency in the range 100 Hz-20 MHz. These studies indicate that the values of ε and tan8 depend on the size of particles. The cole-cole plot of impedance spectroscopy has been used to find the grain size and boundary effect on electrical properties of NF nanograins. The magnetic measurements show the value of saturation magnetization (M_s) is 0.003, 44.95, 38.83, 45.26 emu/g, respectively, observed at 400°, 500°, 600° and 700°C.

5 illus, 23 ref

010894   Singh S K;Mahant A K;Sahu A (Radiation Safety System Div, Bhabha Atomic Research Centre, Trombay, Mumbay-110 085, Email: bhusunil@gmail.com) : Development of radiation monitors for measurement of synchrotron radiation. Indian J pure appl Phys 2012, 50(11), 797-8.

High intensity and predominantly low energy Synchrotron Radiation (SR) are produced at INDUS-II Synchrotron Radiation Source at Raja Ramanna Centre for Advanced Technology (RRCAT). SR monitoring instruments were developed to measure and monitor SR radiations. Salient features of these monitors include high sensitivity, isotropic response, audio alarm indicating radiation levels above 1 mR/h and outputs for controlling the door interlocks. Paper describes the design criteria and results of measurements.

2 illus, 4 ref

010893   Singh P K;Dwivedi A (Physics Dep, Institute of Basic Sciences, Dr B R Ambedkar Univ, Khandari Campus, Agra, Email: pramod0002000@yahoo.com) : Pressure derivatives of bulk modulus for materials at extreme compression. Indian J pure appl Phys 2012, 50(10), 734-8.

The method based on the calculus of indeterminates for demonstrating that all the physically acceptable equations of state satisfy the identities for the pressure derivatives of bulk modulus of materials at extreme compression, has been developed. The specific examples of the Birch-Murnaghan finite strain equation, the Poirier-Tarantola logarithmic equation, the Rydberg-Vinet potential energy equation, the Keane K-primed equation and the Stacey reciprocal K-primed equation, have been considered. Expressions for the bulk modulus and its pressure derivatives have been derived and reduced to the limit of infinite pressure. The expressions thus obtained are useful for further analysis of higher derivative thermoelastic properties.

20 ref

010892   Shinde M S;Ahirrao P B;Patil I J;Patil R S (Physics Dep, P S G V P M'S Arts Science & Commerce Collge Shahada, Nandurbar-425 409, Email: rspatil_shahada@yahoo.co.in) : Thickness dependent electrical and optical properties of nanocrystalline copper sulphide thin films grown by simple chemical route. Indian J pure appl Phys 2012, 50(9), 657-60.

Novel chemical bath deposition (CBD) method has been developed to deposit semiconducting nanocrystalline copper sulphide (Cu₂S) thin films on ordinary glass substrates with different thicknesses. The deposition bath consists of aqueous copper chloride (CuCl₂), ammonia (NH₃) and thiourea [SC(NH₂)₂]. It is found that the deposition parameters significantly influence the quality and the thickness of Cu₂S films. The films were uniform and adherent to glass substrates. The deposited films have been characterized by X-ray diffraction (XRD), Scanning electron microscope (SEM), optical absorption and electrical resistivity. The effect of film thickness on the optical, structural and electrical properties has been studied. The shift of 0.46 eV in the optical band gap energy (E_g) and decrease in electrical resistivity from 6.463 x 10^-2 to 8.973 x 10^-3 Ω-cm and increase in the grain size of Cu₂S crystallites from 30 to 250 nm were observed when the film thickness was varied from 130 to 250 nm.

6 illus, 9 ref

010891   Sharma P S;Datta D (Health Physics Div, HS&EG, Bhabha Atomic Research Centre, Mumbai-400 085, Email: pssharma@barc.gov.in) : calculation of flux due to non-uniform line radiation source and a uniform cylindrical volume source using mathematica. Indian J pure appl Phys 2012, 50(11), 832-5.

Non-uniform line source has a continuous spatial variation of activity along its length. It may not be possible to divide such a source into smaller sources of uniform activity. Such situation may arise in case of a pipe carrying radioactivity in liquid form. A Mathematica based code was developed for calculating uncollided flux due to a line source having Gaussian distribution of activity and also a line source with uniform activity placed in air or a non-attenuating medium for comparison. Uncollided flux due to a uniform cylindrical source behind a slab shield was also calculated by replacing it with an equivalent uniform line source using another Mathematica based code and it's output was compared to a point kernel method based code GUI2QAD-3D. Both the codes employ numerical integration.

3 illus, 7 ref

010890   Sharma A;Bhajan Singh;Sandhu B S (Physics Dep, Punjabi Dep, Patiala-147 002, Email: balvir@pbi.ac.in) : Non-destructive tomographic inspection of pipeline and landmine detection using scattering of gamma photons. Indian J pure appl Phys 2012, 50(11), 793-6.

Scanner system is presented for pipeline inspection and detection of explosives (landmines). The portable system detects the type of liquid flowing through the pipe, its location in land soil and crack position. The method is quite sensitive for small change (-0.1 g-cm^-3) in the density of liquid flowing through the pipe and locating defect of 1 mm width under insulation. The explosives (landmines) such as TNT (C₇H₅N₃O₆) and RDX (C₃H₆N₆O₆) have density less than that of various types of soils and therefore, a measurement of density helps to detect the presence of landmine. The explosive simulating phantom is buried at depth of - 2 cm in soil, so the photons have to penetrate this much distance before interacting with buried material. The scattered intensity originating from interactions of photons with the phantom has the potential to detect the presence of landmine.

7 illus, 4 ref

010889   Sarma K S S;Benny P G;Khader S A;Patkari R K; Nair S (EB Processing Section, RTDD, Bhabha, trombay, Mumbai-400 085, Email: kuppasarma@yahoo.co.in) : Safety aspects of a medium energy industrial electron beam accelerator being utilized for technology demonstration and commercial operations. Indian J pure appl Phys 2012, 50(11), 805-7.

Bhabha Atomic Research Centre (BARC) has installed a unique high pulse-powered 2 MeV electron beam (EB) accelerator for developing industrial applications. It is capable of delivering powered EB up to 20 W average beam power (1200 kW peak pulse power) at energy 1 to 2 MeV. Safety features have been designed for safe utilization during irradiation of large scale products, safety of users, operation staff, industrial products and several types of material handling equipment. Adequate shielding is made for bremsstrahlung radiation with maximum beam energy and power. Safety for ozone emission, high voltage, RF radiation has been addressed. This paper gives an account of overall safety features incorporated in the facility.

2 illus, 3 ref

010888   Sanyasi Rao V V S;Gopika Vinod;Sarkar P K; Vaze K K (Reactor Design and Development Group, Health Physics Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: sanyasirao.vvs@gmail.com) : Application of PSA techniques to synchroton radiation source facilities. Indian J pure appl Phys 2012, 50(11), 776-81.

Synchrotron radiation sources are increasingly being used in research and medical applications. Various instances of overexposure in these facilities have been reported in literature. These instances have led to the investigation of the risks associated with them with a view to minimize the risks and thereby, increasing the level of safety. In nuclear industry, Probabilistic Safety Assessment (PSA) methods are widely used to assess the risk from nuclear power plants. PSA presents a systematic methodology to evaluate the likelihood of various accident scenarios and their possible consequences using fault/event tree techniques. It is proposed to extend similar approach to analyze the risk associated with synchrotron radiation sources.

3 illus, 2 tables, 12 ref

010887   Sahani P K;Haridas G;Sarkar P K (Indus Operation & Accelerator Physics Design Div, RRCAT, Indore-452 013, Email: pksahani@rrcat.gov.in) : Simulations of photoneutron spectra due to incident high energy electrons on tungsten target using FLUKA. Indian J pure appl Phys 2012, 50(11), 863-6.

Bremsstrahlung photons followed by photoneutrons are the major radiation hazards in high energy electron accelerators. These neutrons in high energy electron accelerator are produced by Bremsstrahlung photons through photo nuclear reactions. Monte Carlo code FLUKA was used to generate the photoneutron spectra for 20 MeV, 450 MeV and 2.5 GeV electron (electron energies in Indus facility) hitting 4 mm of tungsten target. The total photoneutron yield was calculated from the generated spectrum for different target thicknesses. The results have indicated the isotropic Giant Dipole Resonance (GDR) neutrons dominating the spectra for the above three incident electron energies. The peak energy of the neutron spectra lies between 0.1-1 MeV for these electron energies. The average neutron energy was calculated and found to be 0.82 MeV, 4.09 MeV and 11.6 MeV for 20 MeV, 450 MeV and 2.5 GeV incident electron energy, respectively. The details of the simulation and results are discussed in the paper.

6 illus, 8 ref

010886   Sahani P K;Haridas G;Sarkar P K (Indus Operation & Accelerator Physics Design Div, RRCAT, Indore-452 013, Email: pksahani@rrcat.gov.in) : Simulation of absorbed dose rate due to synchrotron radiation and shielding thickness for radiation safety at INDUS-2 using FLUKA. Indian J pure appl Phys 2012, 50(11), 818-20.

Indus-2 is a 2.5 GeV electron synchrotron radiation source at Raja Ramanna Centre for Advanced Technology (RRCAT), India. 26 synchrotron radiation (SR) beam lines are planned in Indus-2 for various research applications, Out of 26 several beam lines are in operation and many are in installation stage. Due to intense flux of SR and low energy, the dose rate in the direct beam is high and there is a potential for high radiation exposure. Appropriate shielding hutches are needed to house the beam lines and protect the workers from the radiation hazard. Simulations were carried out using computer code FLUKA to find out the absorbed dose in water due to SR and required shielding thickness in the forward direction to reduce dose within acceptable limits. SR spectrum from Indus-2 in the range 4-100 keV was used for simulating absorbed dose and shielding thickness. It was found that the absorbed dose rate is of the order of 10⁵ Gy/h for the design parameters of Indus-2 (2.5 GeV and 300 mA). Forward shielding thickness of 3mm lead was found to be sufficient to reduce the dose rate to acceptable level for continuously occupied area (<60>1μSv/h). The details of the simulation and results are presented in the paper.

3 illus, 1 table, 4 ref

010885   Rui-Zhou Z;Xiao-Hong L;Xian-Zhou Z (College of Physics and Engineering, Henan Science and Technology Univ, Luoyang-471 003, China, Email: zrzhou@yeah.net) : Molecular structure, vibrational spectra and theoretical NBO, HOMO-LUMO analysis of N-benzoul glycine by DFT and ab-initio HF methods. Indian J pure appl Phys 2012, 50(10), 719-26.

The vibrational frequencies of N-benzoyl glycine in the ground state have been calculated using density functional method (B3LYP) by using 6-311++G(d,p) basis set. Theoretical vibrational spectra have been interpreted by means of potential energy distribution (PEDs) using MOLVIB program. The equilibrium geometry and the thermodynamic functions of the title compound have been performed at HF/6-31G(d,p)/6-31 l++G(d,p) and B3LYP/6-31G(d,p)/ 6-311++G(d,p) levels of theory. A detailed interpretation of the infrared spectra is reported. The theoretical spectrograms for IR and Raman spectra have been constructed. The natural bond orbital analysis has been carried out to explain the charge transfer or delocalization of charge due to the intra-molecular interactions. Energies of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) have been predicted.

4 illus, 6 tables, 19 ref

010884   Razavi R;Behkami A N;Mohammadi S (Physics Dep, Payame Noor Univ, P O Box: 19395-3697 Tehran, Iran, Email: ariarazavi@yahoo.com) : Extracting nuclear density of <. Indian J pure appl Phys 2012, 50(10), 706-8.

The nuclear level density and thermal properties of ⁵⁶Fe have been extracted using the BCS Hamiltonian with inclusion of interacting fermions. Single particle levels for Nilsson potential have been used in the calculations. The shape of the energy and entropy curves has been interpreted as indication of a double phase excitation region and proposed as signature of the pairing phase transition. The results are compared to the experimental data obtained by the Oslo group.

3 illus, 14 ref

010883   Ram Niranjan;Rout R K;Srivastava R;Gupta S C (Applied Physics Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, Email: rkrout@barc.gov.in) : The smallest plasma accelerator device as a radiation safe repetitive pulsed neutron source. Indian J pure appl Phys 2012, 50(11), 785-8.

The development of a portable plasma accelerator unit, the smallest plasma focus device that can be operated to produce pulsed neutrons in 10 Hz repetition rate, has been reported in the present paper. The unit consists of coaxial stainless electrodes with an alumina insulator sleeve. The inner diameter and the effective length of the unit are 4 cm and 12 cm, respectively. The device is operated at 500 J (10 μF, 10 kV). An open air triggered spark gap switch is used. The repetitive operation is achieved by sequentially synchronizing charging pulse and triggering pulse. For a single shot operation, the average yield was (1.3±0.2) x l0⁵ neutrons per shot. For 10 Hz operation, the average yield was (1.4±0.3) x l0⁶ neutrons/s.

6 illus, 10 ref

010882   Rajendra Babu K; (Technical Physics Div, BARC, Mumbai) : Development of an inductively coupled plasma mass-spectrometer (ICPMS). BARC Newsl 2012, (Nov-Dec), 22-7.

Quadrupole based Inductively Coupled Plasma Mass Spectrometer (ICPMS) has been developed at Technical Physics Division, for the elemental determination at trace and ultra-trace levels and their isotope ratio measurements in various materials. The performance of the indigenously developed ICPMS has been tested for sensitivity, detection limits and linearity for different elements. The Sensitivity of the ICPMS was found to be 10-30 x10⁶ cps/ppm, resulting in detection limits ranging from 10-50ppt, depending on the element of interest. Nuclear, Pharmaceutical and Biological samples were analyzed (to describe the operating characteristics and performance of the system).

7 illus, 4 tables, 6 ref

010881   Puppalwar S P;Dhoble S J (NO, Kamla Nehru College, Sakkardara Square, Nagpur-440 009, Email: sjdhoble@rediffmail.com ) : Determination of kinetic parameters of TL of Eu-doped LiNaF₂. Indian J pure appl Phys 2012, 50(11), 855-8.

In the present paper, thermoluminescence (TL) study of Eu doped LiNaF₂ phosphor is reported. A polycrystalline sample of LiNaF₂:Eu was prepared by solid state diffusion method. Formation of compound was confirmed by taking the X-ray diffraction (XRD) pattern. TL glow curves of γ-irradiated LiNaF₂:Eu sample show one glow peak at temperature 168°C. The trapping parameters associated with the prominent glow peak of LiNaF₂:Eu are calculated by using glow curve shape (Chen's) method. The release of holes/electrons from defect centers at the characteristic trap site initiates the luminescence process in this material. The intensity of the TL glow peaks increases with increase of the γ-ray of ⁶⁰Co dose to the sample. A linear TL response is observed in LiNaF₂:Eu in a long span of exposures and it may be used as a TLD material.

4 illus, 2 tables, 13 ref

010880   Patil B J;Patil A J;Chauhan S T;Pethe S N; Krishnan R;Bhoraskar V N;Dhole S D (Physics Dep, Pune Univ, Ganeshkhind, Pune-411 007, Email: sanjay@physics.unipune.ac.in) : FLUKA simulation of 15 MeV linear accelerator based thermal neutron source for radiography. Indian J pure appl Phys 2012, 50(11), 814-17.

FLUKA simulation has been carried out using 15 MeV LINAC to design thermal neutron source for radiography. In this case, a neutron collimator has been designed along with e-γ target, γ-n target, moderator and shielding. The γ-n target has been optimized based on their photonuclear reaction threshold. The moderating properties have been studied for a few light elements to optimize best suitable moderator for radiography system. To get best values of collimator parameters such as collimation ratio, gamma content, neuron fluence rate, cadmium ratio, beam uniformity etc., a FLUKA simulation was carried out. The collimator has been optimized with cadmium lining square cone to capture the scattered thermal neutrons and the collimation ratio to L/D=20. The neutron fluence rate and neutron to gamma ratio of the optimized facility at the object plane is 1.1 x 10⁵ n cm^-2 s^-1 and 1.0 x 10⁵ n cm^-2 mR^-1.

6 illus, 7 ref

010879   Nayak M K;Sahani P K;Khare M;Sahu T K;Haridas P;Vipin Dev;Dashora S;Dhamgaye V;Haridas G;sarkar P K (Health Physics Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: nayak@rrcat.gov.in) : Experimental investigation of synchrotron and Bremsstrahlung dose at lithography beam line of Indus-2 SRS. Indian J pure appl Phys 2012, 50(11), 829-31.

Measurement was performed during the initial trial operation of Lithography beam line (BL-07) of Indus-2 SRS. Transmission of SR through the beam line was optimized by providing bump to electron beam, prior to the measurement. Thin window ion chamber was used for SR measurement in direct beam. Ion current is converted to exposure rate using a calibration factor obtained with respect to Co-60 source. 6 mm thick Cu absorber was used for eliminating SR contribution during BR dose measurement. The exposure rates obtained are 3.83xl0³ Gy/h/mA for SR and 4.2x10^-4 Gy/h/mA for BR. Energy of bremsstrahlung radiation was also experimentally evaluated using attenuation technique. Details of these measurement and results are presented.

3 illus, 1 table, 4 ref

010878   Nandy M;Lahiri C (NO, Saha Institute of Nuclear Physics, Kolkata-700 064, Email: maitreyee.nandy@saha.ac.in) : Radioactivity generation in Pb target by protons-a comparative study from MeV to GeV. Indian J pure appl Phys 2012, 50(11), 761-5.

In an Accelerator Driven Subcritical System (ADSS), choice of the target is decided by several factors like neutron yield, heat generation, ease of cooling, possibility of fire hazard, generation of chemically toxic elements and radioactive nuclides, running cost of the accelerator, etc. ^natPb is one of the probable targets for an ADSS. In the present work, we have estimated induced activity in a ^natPb target by primary proton beam in the energy range of 20 MeV up to 2.0 GeV using reaction model codes ALICE-91, TALYS-1.2, EMPIRE-2.19 and QMD. The energy range studied spans the entire energy interval used for target property study to practical application of an ADSS. At several hundreds of MeV, some of the major contributors to induced activity are projectile-like fragments, such as, ³H. The maximum activity produced is of the order of 10⁶-10⁷ MBq over the whole energy range. Some chemically toxic elements like Xe, Hg are also formed in significant amount.

8 illus, 1 table, 9 ref

010877   Mittal K C (Electron Beam Centre, Accelerator & Pulse Power Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: kcm@barc.gov.in) : High power electron accelerators for radiation processing and its safety aspects. Indian J pure appl Phys 2012, 50(11), 772-5.

Electron accelerators from 500 keV to 10 MeV energy are employed for surface irradiation, food preservation, medical sterilization, cargo scanning and other industrial products. At EBC, a 10 MeV Linac has been indigenously developed and is operational for radiation processing. This is an on-axis coupled cavity standing wave type of RF linac operating with 50-70 keV electron gun having LaB₆ cathode and klystron-based RF source at 2856 MHz. The linac is currently operating at 10 MeV, 130 mA (peak), 10 μs pulses at a prf of 415 Hz and is employed for various experiments. A similar 9 MeV linac is operational for cargo-scanning. A compact 6 MeV linac is under development. A 500 keV, 3 kW dc accelerator based on Cockroft Walton multiplier has been operational for industrial surface processing. A 3 MeV dc accelerator based on parallel coupled multiplier column is operational at 1 MeV, 4.6 kW level. A 700 keV, 5 kW dc machine for cross-linking and graft polymerization is under development. A 100 MeV, 100 kW electron Linac for producing intense neutron source has been proposed for development. Technological developments, operating experiences, utilization for industrial applications and safety aspects of all facilities are described.

3 illus, 11 ref

010876   Misdaq M A;Idane S (Nuclear Physics and Technique Laboratory, Faculty of Sciences Semlalia, BP 2390, Cadi Ayyad Univ, Marrakech, Morocco, Email: misdaq@ucam.ac.ma) : Study of <. Indian J pure appl Phys 2012, 50(10), 685-96.

Coffee and green tea drinks as well as sugar are widely consumed by Moroccan population. ²³⁸U, ²³²Th, ²²²Rn and ²²⁰Rn contents have been measured inside different soil, sugar beet and table sugar material samples collected in different areas of Morocco by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). The transfer of contents ²³⁸U, ²³²Th and ²²²Rn between soil and sugar beet and that between sugar beet and table sugar has been measured. To explore the exposure pathway of ²³⁸U, ²³²Th and ²²²Rn to the organs and tissues of consumers from the ingestion of coffee and green tea drinks, contents of these radionuclides have been measured in the drinks. The effect of the nature water and pollution on the concentrations of these radionuclides in coffee and green tea has been investigated. Annual committed effective doses due to ²³⁸U, ²³²Th and ²²²Rn from the ingestion of table sugar and coffee and green tea drinks by the members of the general public and workers have been determined. The maximum total committed effective dose due to ²³⁸U, ²³²Th and ²²²Rn from the ingestion of tea drinks by the members of the Moroccan rural population was found to be equal to 0.13 mSv y^-1.

9 tables, 36 ref

010875   Mandlik N;Bakare J S;Sahare P D;Bhoraskar V N;Dhole S D (Physics Dep, Pune Univ, Ganeshkhind, Pune-411 007, Email: sanjay@physics.unipune.ac.in) : Thermoluminescence and photoluminescence properties of K₂Ca₂(SO₄)₃:Cu nanophosphor for gamma radiation dosimetry. Indian J pure appl Phys 2012, 50(11), 859-62.

Nanocrytstalline K₂Ca₂(SO₄)₃:Cu was synthesized by chemical co-precipitation method and annealed at 400°C. These nanocrytstalline samples were irradiated with gamma radiation for the dose varying from 500 Gy to 2000 Gy. The pre and post irradiated samples were characterized by the techniques such as XRD, SEM, UV, FTIR, photoluminescence (PL) and thermoluminescence (TL). XRD spectra show the orthorhombic structure and the crystallite size - 25 nm. The same is also confirmed in SEM, where the size of nanoparticles was varied from 20 to 40 nm and also shows monodispersed. Formation of the compound was also checked by FTIR, where the S-O stretching and bending mode have been observed. Whereas, in case of UV visible spectra, the band gap observed to be marginally decreased with gamma dose. In PL spectra, the emission bands are observed at 403 and 419 nm, respectively and their respective intensity increases linearly with the increase in gamma dose. In TL spectra, two dosimetric peaks have been observed at 144°C and 287°C, respectively and their intensity tends to be increased with gamma radiation dose. This particular aspect shows the wide range linear TL response to the high gamma dose. Moreover, a significant shift in the peak towards lower temperature has been observed. This indicates the disorganization of the initial energy bands in the nanophosphor. In conclusion, the K₂Ca₂(SO₄)₃:Cu nanophosphor is useful for high dose gamma ray dosimetry.

8 illus, 6 ref

010874   Makwana R;Vala S;Abhangi M;Jakhar S;Rao C V S;Basu T K (NO, Institute For Plasma Research, Neutronics Group, Gandhinagar-382 428, Email: rajnikant@ipr.res.in) : Shielding design of the proposed laboratory for an intense 14 MeV neutron generator. Indian J pure appl Phys 2012, 50(11), 799-801.

The proposed intense 14 MeV neutron source at IPR is accelerator based using the T(d,n)α reaction. This facility will be indigenously built and used for the fusion Neutronics studies. Deuterium ions will be accelerated up to 300 keV in an electrostatic acceleration column delivering a maximum beam current of 20 mA. The beam will be made to impinge a water cooled, rotating tritium target. The expected neutron yield will be - 10¹² neutron per second. This paper describes the preliminary design of the neutron generator and the MCNP model results of the shielding calculations. The calculation of dose rate has been carried out for the optimum thickness of concrete shield.

5 tables, 6 ref

010873   Londhe N D;Anand R S (Electrical Engineering Dep, IIT Roorkee, Roorkee-247 667, Email: ndlondhe.iitr@gmail.com) : Ultrasound shock wave propagation and generation of harmonics in biological tissues. J pure appl Ultrasonics 2011, 33(4), 77-87.

In this paper, two theoretical methods for the description of nonlinear ultrasound wave generated from axis symmetric circular source and propagation in soft human tissues is described. Burgers' equation has been used to model the nonlinear propagation of single sinusoidal wave of finite amplitude. In the first method, the analytical solution of Burgers' equation was achieved by using Fubini method in preshock region while weak shock theory applied in postshock region for lossless medium. In case of lossy medium, the analytical solution of Burgers' equation is achieved by using linear diffusion equation via Hopf-Cole transformation in preshock region and Fay's equation in postshock region. In the second method the operator splitting methodology is implemented in which absorption term is solved using Crank Nicholson Finite Difference (CNFD) method in time and nonlinear term by using analytical method at each step for both lossless and lossy medium. Both the methods are solved in MATLAB. The results have been shown for waveform distortion and shock formation radiated by circular piston source for lossless and lossy tissue mediums. The analytical study of fundamental, second and third harmonic components variation along the distance of propagation has been done using both proposed methods and has been compared.

14 illus, 12 ref

010872   Kumar R;Mahesh R;Shanmugapriyan B;Kannappan V (Physics Dep, The New College, Chennai-600 014, Email: kumss73@gmail.com) : Volumetricm viscometric, acoustic and refractometric studies of molecular interactions in certain binary systems of o-chlorophenol at 303.15 K. Indian J pure appl Phys 2012, 50(9), 633-40.

This paper describes the results of our experimental study on four binary systems containing o-chlorophenol (OCP) as the common component and the second component is, cinnamaldehyde orbenzaldehyde or N,N-dimethylacetamide or n-hexane. The measured speed of sound (U), density (p), viscosity (η3) and refractive index (μ) and the computed acoustical parameters at 303.15 K and at atmospheric pressure, identify strong molecular interactions through hydrogen bonding in aldehyde and amide systems with OCP while weak interaction in n-hexane system. The influence of structure of components on the existing interactions has also been revealed by the behaviour of volumetric parameters. The sign and magnitude of excess parameters clearly indicate the presence of specific interactions among the components. The excess parameters were fitted to polynomial type Redlich-Kister (RK) equation and the coefficients of the fitting were found to support the present investigation. The validity of various theoretical models applied to the present systems has been studied through the calculated values of absolute average percentage deviation (AAPD).

4 illus, 4 tables, 36 ref

010871   Kumar M; (Accelerator & Pulse Power Div, Bhabha Atomic Research Centre, Mumbai, Email: mukesh_kishu@yahoo.com) : Utilization of 10 MeV RF electron linear accelerator for research and industrial applications. Indian J pure appl Phys 2012, 50(11), 802-4.

10MeV RF electron linear accelerator (Linac) is regularly used at Electron Beam Centre (EBC) Kharghar, BARC to demonstrate the radiation processing of different research and industrial applications. The use of 10 MeV electron beam for environment friendly waste disposal of printed circuit board (PCB) has been demonstrated. The 99.9% pure Cu foil has been extracted from the PCB by imparting 300 kGy of radiation dose. The power diode of Bharat Heavy Electricals Limited (BHEL) has been irradiated by imparting a dose of 4 kGy to achieve reduction in reverse recovery time (T_rr) from 15 (as to 6 μs. An irradiation experiment of polymer blend samples has been conducted by RTDD, BARC at EBC to increase the tensile strength of blends of low density polyethylene (LDPE) and ethylene vinyl acetate (EVA) from 6 MPa to 7.8 MPa by imparting a dose of 100 kGy. The alanine-EPR dosimetry has been done to optimize process parameters for food irradiation. The semolina (cream of wheat) packets are irradiated at the D_min (minimum dose level) of 250 Gy and D_max (maximum dose level) of 1 kGy. The dose between the D_min and D_max has been delivered using 10 MeV electron beam, and packets are kept to collect further data. Various research experiments of BARC and other universities have been carried out to study the effects of irradiation on materials.

3 illus, 4 ref

010870   Karar N;Srivastava A K;Kotnala R K (NO, CSIR-National Physical Laboratory, Dr K S Krishnan Road, New Delhi-110 012, Email: nkarar78@gmail.com) : Interdependence of nano grain size, alloying effects and magnetic properties of Ni-Cu-Al alloys. Indian J pure appl Phys 2012, 50(10), 727-33.

The remarkable modification in physical and magnetic properties of ternary Ni, Cu and Al based ensemble of ball milled nanoparticle alloys and their crystalline shape with grain size and composition has been studied in the present paper. The onset of crystalline changes have been correlated to grain size and alloying content. A sharp decrease in ferromagnetism maintaining the cubic symmetry with grain size and alloying was also revealed. These alloys show two phase transitions, one near room temperature and the other near 80°C compared to 200°C for similar bulk compositions. Such observations have been explained and their possible usage is being explored.

5 illus, 1 table, 26 ref

010869   Joshi D P;Sharma K (Physics Dep, D B S (PG) College, Dehradun, Uttarakhand, Email: dpj55@rediffmail.com) : Effects of grain boundaries on the performance of polycrystalline silicon solar cells. Indian J pure appl Phys 2012, 50(9), 661-9.

Comprehensive carrier recombination model under optical illumination near grain boundaries (GBs) is proposed by considering the asymmetric Gaussian energy distribution of GB interface states model. A new recombination velocity S(L_n) is proposed to study the dependence of effective diffusion length of minority carriers on grain size and GB interface state density. The dependence of GB space charge potential barrier height (_qV_g), the recombination velocities, and polycrystalline silicon (PX-Si) solar cell parameters on grain size, illumination level, and GB interface state density have also been studied. It is observed that the efficiency of solar cells is mainly determined by the potential barrier height ^qV_g. Considering the effect of vertical GBs in the junction depletion region of a solar cell, it is also observed that their effect is smaller in the small grain size range as compared to that in the large grain size range. A reasonably good agreement is obtained between the theoretical predictions and the available experimental data.

10 illus, 2 tables, 37 ref

010868   Joseph P;Narayana Y;Bhat N N;Santra S;Thomas R G;Gupta S K (Studies in Physics Dep, Mangalore Univ, Mangalagangotri-574 199, Email: narayanay@yahoo.com) : Determination of relative biological effectiveness of 3.2 MeV proton beam from folded tandem ion accelerator. Indian J pure appl Phys 2012, 50(11), 789-92.

In the present study, DNA damage induced by proton beam from Folded Tandem Ion Accelerator (FOTIA) and gamma radiation from a ⁶⁰Co source on human tumor adeno carcinoma (HT 29) cells has been studied. Dosimetry for proton radiation has been carried out using surface barrier semiconductor detectors and flux was adjusted to be 1.6xl0⁶ with fluence variation to deliver different doses. Proton beam of intermediate LET (12.5 keV μm^-1), which has a penetration of 150 μm in tissue, was used for the study. Radiation damage induced on cells was evaluated by comet assay and the comet parameter used was Olive Tail Moment (OTM). The average RBE was calculated from the proton and gamma dose required for the iso-effective OTM.

2 illus, 1 table, 8 ref

010867   Jeyavijayan S;Arivazhagan M (Physics Dep, J J College of Engineering and Technology, Tiruchirappalii-620 009, Email: jjmarivu@yahoo.co.in) : FTIR, FT-raman spectra and DFT analysis of m-nitrobenzaldehyde oxime. Indian J pure appl Phys 2012, 50(9), 623-32.

The Fourier transform infrared (FTIR) and FT-Raman spectra of m-nitrobenzaldehyde oxime (MNBO) have been recorded in the regions 4000-400 cm^-1 and 3500-50 cm^-1, respectively. Utilizing the observed FTIR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of the compound have been carried out. The optimum molecular geometry, harmonic vibrational frequencies, infrared intensities and Raman scattering activities, have been calculated by density functional theory (DFT/B3LYP) method with 6-31+G(d,p) and 6-311++G(d,p) basis sets. 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 MNBO is also reported based on total energy distribution (TED). The calculated HOMO and LUMO energies show that charge transfer occur within the molecule.

4 illus, 6 tables, 28 ref

010866   Jaya Madhuri N;Glory J;Naidu P S;Ravindra Prasad K (Physics Dep, S.V.U.P.G. Centre, Kavali-524 201, Email: nissi.joicy@gmail.com) : An ultrasonic study of aqueous solutions of various drugs used for cough- jacobson's theory of compressibility. J pure appl Ultrasonics 2011, 33(4), 92-5.

Six drugs belonging to one class which are used for reducing cough have been chosen for an ultrasonic study. These solutions have in them as major components-Chlorpheniramine maleate/diphenydramine hydrochloride/ambroxol hydrochloride/terbutalline sulphate/codeine phosphate/herbal syrup. Ultrasonic velocity and density have been measured in the aqueous solutions of these systems at 303.15K. Deviations in velocity and compressibility have been computed. Also the effect of these systems on the structure of water has been analysed employing Jacobson's theory of adiabatic compressibilities.

5 illus, 1 table, 10 ref

010865   Hussain S;Gayen R N;Dutt M B;Pal A K (Instrumentation Science Dep, USIC Building, Jadavpur Univ, Calcutta-700 032, Email: msakp2002@yahoo.co.in) : Surface modification of GaAs induced by argon ion implantation. Indian J pure appl Phys 2012, 50(9), 650-6.

Surface modification of GaAs (100) due to Ar⁺ ion bombardment has been studied by measuring optical, AFM, SEM, Raman and PL measurements. GaAs was bombarded with 250 keV argon ions with three different doses of 1x10¹⁶ cm^-2, 1x10¹⁵ cm^-2 and 1x10¹⁴ cm^-2. AFM studies indicated that the surface became rougher with ion bombardment (dose) and the surface roughness increased from 0.706 nm for un-bombarded GaAs to 3.671 nm for bombarded samples. Peaks shifted to lower 29 values for bombarded samples. The full width at half maxima (FWHM) of the XRD peaks for reflections from (200) and (400) planes of GaAs increased for films bombarded with increased Ar⁺ fluxes and increase in FWHM for (400) plane peak is quite significant. The LO peak at -290 cm^-1 of the Raman spectra shifted to lower wave number and became broader with the Ar⁺ flux. PL spectra showed a strong luminescence peak at - 1.5 eV followed by two smaller peaks located at -1.40 eV and 1.1 eV. Photoluminescence bands at - 1.5 eV band were assigned to annihilation of free and localized excitons by small donors and acceptors. The shoulders at -1.48 eV and -1.47 eV represented the transition due to free-to-bound recombination and the defects GaAs.

7 illus, 28 ref

010864   Harish V;Nagaiah N;Harish Kumar H G (Physics Dep, Govt. First Grade College, Shimoga-577 201, Email: harishvenkatareddy@rediffmail.com) : Lead oxides filled isophthalic resin polymer composites for gamma radiation shielding applications. Indian J pure appl Phys 2012, 50(11), 847-50.

Particulate polymer composites of isophthalic resin (ISO) filled with three lead oxides (PbO, PbO₂ and Pb₃O₄) were prepared with different filler concentrations and investigated for radiation shielding properties of gamma rays from Ba-133, Cs-137 and Co-60 point sources. Among the three composite combinations, ISO+PbO composites yield better density values than the other two due to high density of the filler which contains large lead fraction and fine dispersability in the polymer matrix. Dispersion and particle size of filler were also studied by morphological analysis of the composites using Scanning Electron Microscope. Attenuation coefficients were found to increase with the increased filler content in the composites. ISO+PbO composites have found to outperform than ISO+PbO₂ and ISO+Pb₃O₄ composites. Excellent performance of ISO+PbO composites can be attributed to their high lead content as well as fine filler dispersion in the polymer matrix. Further, these ISO+PbO composites when compared to conventional shielding materials perform as strong contenders to barite, steel and concrete at low gamma ray energies. Even at higher gamma ray energies considered, they perform satisfactorily and are very much comparable to steel and concrete.

8 illus, 6 ref

010863   Ghosh D;Deb A;Mondal M;Biswas Ghosh S (Nuclear and Particle Physics Research Centre, Physics Dep, Jadavpur Univ, Kolkata-700 032, Email: mitalimon@gmail.com) : Characteristics of pion production in ring-like events using entropy index. Indian J pure appl Phys 2012, 50(9), 617-22.

The possible chaotic behaviour in production of ring like structured events and jet like structured events in ¹⁶O-AgBr interactions at 60 AGeV with the help of a newly defined parameter, entropy index μ_q has been studied. The data reveal less chaoticity in the pionisation process of ring like events with respect to that of jet like events.

6 illus, 2 tables, 13 ref

010862   Choubey A K;Brahme N;Bisen D P (NO, Christain College of Engineering & Technology, Kailash Nagar, Bhilai, Chhattisgarh-490 026, Email: anil.choubey@hotmail.com) : Synthesis of SrAl₂O₄: Eu phosphor by combustion method and its possible applications for mechanoluminescence dosimetry. Indian J pure appl Phys 2012, 50(11), 851-4.

Eu doped strontium aluminate phosphor (SrAl₂O₄:Eu) was synthesized by combustion method using urea as a reducer at initiating temperature of 600°C. The mechanoluminescence (ML) of SrAl₂O₄:Eu and their suitability for radiation dosimetry have been investigated. Eu doped SrAl₂O₄ is a good dosimeter having linear response up to about 1180 Gy of γ-radiation dose. Two peaks have been found in time versus ML intensity curve. The peak of ML intensity versus time curve increases with increasing dose of γ-radiation. The total ML intensity (area below the curve) also increases with γ-dose.

7 illus, 16 ref

010861   Chern-Sheng L;Shu-Hsien F;Mau-Shiun Y;Chingfu T;Teng-Hsien L (Automatic Control Engineering Dep, Feng Chia Univ, Taichung, Taiwan, Email: lincsfcu@gmail.com) : Measurement of microstructure in micro electro mechanical systems using optical interferometric microscope. Indian J pure appl Phys 2012, 50(9), 641-9.

Automatic measurement system for micro electro mechanical element with optical interferometric microscope is presented in the paper. The system introduces a novel method to calculate the central dark fringe (intensity minimum) and central bright fringe (intensity maximum) in the image. The changing of height in asymmetric micro-structure, based on the phase definition of interference fringe can be calculated. Interferometric image information is derived through image processing method, and innovated contour line algorithm is used to build up micro-structure 3D profile. In the experiments, the total processing time for five parts of element could be reduced to less than 5 s and the system error is less than 0.02 μrn.

13 illus, 24 ref

010860   Chandak R M;Poudel S K;Naik S S;Santosh Kumar;Kulkarni V B;Shaikh I J A;Mukhopadhyay R (Solid State Physics Div, BARC, Mumbai) : Data acquisition and control electronics of neutron scattering instruments under NFNBR at BARC: an overview. BARC Newsl 2012, (Nov-Dec), 34-40.

National Facility for Neutron Beam Research (NFNBR) has been created as a part of the Solid State Physics Division (SSPD) during early nineties to cater to the needs of the Indian scientific community in the field of neutron beam research. Scientists from BARC, other DAE units, universities and national laboratories use this facility through collaborative research projects with SSPD scientists. Many of these collaborations are being supported by UGC DAE Consortium for Scientific Research, Board of Research in Nuclear Sciences (BRNS) and other agencies. At present the facility is mainly concentrated at DHRUVA research reactor at BARC. NFNBR has various neutron scattering experimental set-ups for basic and applied research in condensed matter. A brief description of Data Acquisition and Control Electronics associated with these instruments, developed and maintained in-house is provided.

9 illus, 5 ref

010859   Chakrabarti A (NO, Variable Energy Cyclotron Centre (VECC), 1/AF Bidhan Nagar, Kolkata-700 064, Email: alok@vecc.gov.in) : The radioactive ion beam project at VECC and the safety issues. Indian J pure appl Phys 2012, 50(11), 766-71.

The Radioactive Ion Beam (RIB) project aims at accelerating beta-unstable secondary beams of atomic nuclei produced by bombarding a target by primary beam such as protons and alpha-particles. A number of ion-sources and linear accelerators have already been built for this project, which involves construction of an Isotope Separator on Line (ISOL) type RIB facility. At present beams are accelerated up to about 415 keV/u using one RF Quadrupole linac and three IH Linacs. Finally, with the addition of a few more Linac modules beams would be accelerated to about 1.3 MeV/u. This energy is as such quite low, below the coulomb barrier except at low masses. Also since the RIBs are secondary beams, their intensity is often below 10⁷ particles per second. Thus, lack of activity at the secondary target rather than activity is what throws challenges to the experimenters and designers of such a facility. The situation is, however, not so simple at the production target station, where the activity induced by primary beam would be very high especially for actinides targets. One often needs to design very special chambers with quick connect-disconnect features to remotely disengage and remove the active part of the target chamber into a heavily shielded box for transfer to a hot store. This paper gives an overview of the present status of VECC RIB facility. Safety issues related to this project would be discussed and steps already taken to ensure the same at the present stage of the facility, and those that are being planned to ensure safety for the facility in its final form would be discussed.

6 illus, 1 table, 15 ref

010858   Bhargava P;Sharma V K (Health Physics Div, Bhabha Atomic Research Centre, Mumbai-400 085, Email: pradeepb@barc.gov.in ) : Shield assessment of the radioactive waste storage facility. Indian J pure appl Phys 2012, 50(11), 836-9.

Alpha-contaminated solid radioactive waste is generated in several plants in the front-end and back-end of the nuclear fuel cycle. Typical plants producing such waste include MOX fuel fabrication plants, fuel reprocessing plants and waste management facilities. The main contaminants of concern are uranium, plutonium and the other actinides. The disposal of such waste needs to be carried out in accordance with regulatory guidelines which require that alpha-contaminated solid waste consignments at levels <62> 4000 Bq/g may not be disposed of in the near-surface disposal facilities. It is recommended that such waste should be stored temporarily in storage facilities from where they can be retrieved at a later date for ultimate disposal. The storage and disposal of alpha-contaminated waste is occasionally complicated by the co-existence of high radiation fields from the β-γ sources present in the waste. Typical examples include ^137+134Cs and ⁶⁰Co on zircaloy hulls. This requires that the alpha waste carrying high external fields be stored in shielded vaults. Since the analysis involves for the most part shielding of large number of sources and their complex geometries, an elaborate point Kernel method based computer code QAD CG is used. Sources in the drums containing Alpha Waste are estimated on the basis of maximum contact dose rate on the drum which is 6960 mGy/h. The gamma emitting nuclide shall be assumed to be represented by ¹³⁷Cs to convert the given dose rate in to the activity. A selection of 1000 mm as the side wall and top slab concrete thickness is found to be acceptable. The maximum lateral dose rate is 0.131 μGy/h, and maximum top slab dose rate is 0.651 μGy/h.

3 tables, 7 ref

010857   Arivazhagan M;Kavitha R (Physics Dep, A A Government Arts College, Musiri-621 211, Email: jjmarivu@yahoo.co.in) : FT-IR, FT-Raman and theoretical NBO, NLO and MESP analysis of 4-bromoveratrole by ab-initio HF and DFT methods. Indian J pure appl Phys 2012, 50(10), 709-18.

The Fourier Transform Infrared (FTIR) and FT-Raman spectra of 4-bromoveratrole (4BV) have been recorded in the region 4000-400 cm^-1 and 3500-50 cm^-1, respectively. The experimental vibrational frequencies are compared with the wave numbers obtained theoretically by ab-initio HF and DFT-B3LYP gradient calculations employing the standard 6-311++G(d,p) basis set for the optimized geometry of 4BV. The values of the first-order hyperpolarizability (β) of the investigated molecule are computed using DFT quantum mechanical calculations. The calculation results also show that the molecule might have microscopic nonlinear optical (NLO) behaviour with non-zero values.NBO analysis has been carried out at DFT level. NBO study explains charge delocalization of the molecule. Mulliken's net charges have been calculated and compared with the atomic natural charges.

5 illus, 6 tables, 42 ref

010856   Anand S;Singh K D;Rana S;Sharma V K (Safety Studies Section, Health Physics Div, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, Email: sanand@barc.gov.in) : Note on the accident dose mapping of the fuel handling area of a fuel reprocessing plant using Monte Carlo techniques. Indian J pure appl Phys 2012, 50(11), 821-4.

Radiation dose mapping of the Spent Fuel Storage Building (SFSB) housing large number of Pressurised Heavy Water Reactor (PHWR) spent fuel bundles has been carried out using Monte Carlo based shielding code. The general methodology followed in this study involves postulation of severe accident sequences and their evaluation for on-site consequences. These accidents are extremely improbable accidents that might occur due to a combination of human error, violation of operating procedure, and failure of maintenance procedure. Probabilities were not calculated in this exercise. Two severe accident scenarios are postulated for this analysis: (1) Accidental falling of the fuel transfer cask containing irradiated fuel bundles and (2) Loss of water cover to the spent fuels in the storage pool. Since the analysis involves for the most part shielding of large number of sources and their complex geometries, an elaborate Monte Carlo model of the SFSB has been generated. Sources in the fuel rods are estimated using the inventory code, ORIGEN2, and the dose rates at specified location of interest have been calculated using shielding code. The results are further discussed.

3 illus, 4 tables, 4 ref

010855   Acharyulu G V S G;Sankari M;KiranKumar P V; Suryanarayana M V;Mukherjee T (National Centre for Compositional Characterisation of Materials, Chemistry Group, BARC, Mumbai) : Indigenous development of high-resolution atomic beam fluorescence spectroscopy facility for precision measurements of isotope shifts and hyperfine structure. BARC Newsl 2012, (Nov-Dec), 28-33.

A compact and versatile ultra-high vacuum chamber in combination with a resistively heated graphite tube atomic beam apparatus for sub-Doppler fluorescence experiments has been designed and developed. The spectral resolution achieved in the developed system is more than adequate to clearly observe all the sub-Doppler hyperfine features in the D2 spectrum of rubidium. The compact interaction geometry, flexibility in changing the atomic beam source and simplicity of the entire set up makes it useful for the measurement of isotope shifts and hyperfine structure with a precision of <60>100 kHz. The developed system is versatile enough and can be adopted to carry out high resolution atomic fluorescence experiments on radio-active isotopes after making minor modifications to ensure radiation safety. The spectral resolution and small sample size requirement would enable accurate measurements of nuclear parameters such as nuclear size, deformation, magnetic moments, quadrupole moments, spins etc. This finds applications in AVLIS and ADSS programmes.

6 illus, 8 ref