014304   Kalyana Raman S B;Arulmozhi K T;Uvarani R (Physics Dep, Annamalai Univ, Annamalainagar-608 002) : Correlation analysis of ultrasonic velocity and grouped characteristic parameters of pure liquids using multiple regression technique. Acta Cienc Indica-Phys 2004, 30(3), 323-7.

Velocity of ultrasonic waves through a liquid is strongly influenced by certain characteristic parameters of the liquid like molecular weight (M), density (ρ), viscosity (η), surface tension (σ), dielectric constant (ε), space filling factor (r), collision factor (s), etc.. These parameters, when grouped together, exhibit high correlation with the velocity. Multiple regression analysis has been successfully employed to find the correlation between the velocity of ultrasonic waves and these grouped parameters.

4 tables, 11 ref

014303   Jain S K;Jain A;Hannurkar P R (RF & Microwave Section, Accelerator Programme, Centre for Advanced Tec, , Indore-452 013, Email: skjain@cat.ernet.in) : Indigenous development of a low cost high power 2 kW (CW), 2.45 GHz microwave system. Indian J pure appl Phys 2004, 42(12), 896-901.

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

7 illus, 15 ref

014302   Frost R L;Erickson K L;Weier M;Mills S (Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland Univ of Technolog, GPO Box 2434, Brisbane Queensland 4001, Australia, Email: r.frost@qut.edu.au) : Raman spectroscopy of the phosphate minerals: Cacoxenite and gormanite. Asian Chem Lett 2003, 7(4), 197-203.

The structures of cacoxenitc and gormanite have been studied using Raman spectroscopy at 298 and 77 K complimented with infrared spectroscopy. Two sets of well-defined hydroxyl stretching vibrations are observed for cacoxenite attributed to Al-OH and Fe-OH stretching bands. Additional bands in the range 3274-3418 cm^-1 are assigned to water stretching vibrations. In contrast the spectral profile of cacoxenite is a broad profile centred at 3255 cm^-1. No distinct OH stretching vibrations arc observed. The reason is the cacoxenite structure has large diameter pores in which the water is found. Multiple PO₄ stretching vibrations are observed indicating non-equivalent phosphate anions in both the structure of gormanite and in cacoxenite.

1 table, 4ill, 38 ref

014301   El-Bahay M M (Physics Dep, Faculty of Science, Girls Branch, Al-Azhar University, Nasr City 11884, Cairo, Egypt) : Effect of Indium addition on Sn-9% Zn rapidly solidified alloy. Ultra Scient phys Sci 2004, 16(3), 409-16.

Six Sn₉₁ Zn_9-x In_x alloys were quenched from the melt to room temperature by melt spinning. The physical properties investigated were X-ray diffraction to identify the structure of the rapidly solidified (melt spun) alloys. The thermal analysis, including differential thermal analysis (DTA) and specific heat were measured. The electrical resistivity, the elastic modulus, internal friction, hardness, wetting characteristic and the structure change are greatly affected by adding the Indium to a Sn-9% Zn rapidly solidified alloy at low levels. The minimum value of the contact angle is 31.4° for Sn₉₁Zn₆In₃ alloy. Also it has a better properties such as lower resistivity, higher Young's modulus, internal friction and hardness. It is also interesting to note that Ledbetter's theoretical values of μ/E are in a good agreement with the experimental results.

4 illus, 6 tables, 21 ref

014300   Ekhelikar S;Bichile G K (Physics Dep, N V Degree College, Gulbarga-585 103) : Synthesis and structural characterization of Bi₂O₃-M₂O₃ (M=Dy and Pr) binary systems. Indian J pure appl Phys 2004, 42(12), 912-15.

The binary systems Bi₂O₃-O₃ and Bsi₂O₃-Pr₂O₃ have been investigated by doping Dy₂O₃ and Pr₂O₃ in the composition range 10-40 mole % prepared by ceramic method. From the phase evolution studies of Dy₂O₃ doped samples, it was observed that fluorite structured f c c phase is stabilized for the composition range 10-40 mole %. The stability of δ-phase was affected by the heat treatment temperatures. The higher the content of dopant concentration, the higher was the sintering temperature. The lattice parameter for Dy₂O₃ doped samples decreased with the increase of dopant concedntration and obeyed Vegard's rule. From the structural studies of Pr₂O₃ doped sample rhombohedral phase was found for 10 to 30 mole % of dopant concentrations. For 40 mole % of dopant concentration, the impurity peaks were observed in the XRD patterns along with rhombohedral phase. The unit cell parameters for Pr₂O₃ doped samples were evaluated on hexagonal settings.

3 illus, 2 tables, 12 ref

014299   Edwards H G M;Nik Hassan N F (Chemical and Forensic Sciences, The School of Pharmacy, Bradford Univ, Bradford, West Yorkshire BD7 1DP, UK, Email: h.g.m.edwards@bradford.ac.uk) : Evaluation of Raman spectroscopy for the nondestructive differentiation between Elephant and Mammoth ivories. Asian Chem Lett 2003, 7(4), 185-96.

The Raman spectra of modem and ancient ivories are reported using Fourier - Transform conventional dispersive and remote-sensing portable Raman Spectroscopy, all with near infrared laser excitation (1064 and 785nm). The ability to characterize ivory specimens from the African elephant (Loxodonta africana), Asian elephant (Elephas maximtts) and from the extinct proboscid mammoth (Mammuthus primigenus) was evaluated. Specimen age ranged between the present and 125 kyears . FT Raman Spectroscopy produced the best quality spectra for differentiation purposes. The application of a fibre probe coupled to a Raman spectrometer for the identification is also demonstrated and proposed for the in situ characterisation of suspected contraband ivories at airports.

7 illus, 1 table, 12 ref

014298   Dwivedi A K (Physics Dep, R.S.K.D., P.G. College, Jaunpur) : Self-similar isothermal expansion of a gas in non-homogeneous medium. Acta Cienc Indica-Phys 2004, 30(3), 255-8.

Deals with a self similar isothermal expansion of a gas in non-homegeneous medium, driven by an expanding piston. The nature of the flow variables to be dependent on shock radius obeying a power law. The nature of flow variables are illustrated through tables.

4 tables, 11 ref

014297   Dwivedi A K (Physics Dep, S.K.D. P.G. College, Jaunpur) : Similarity solutions for plane, cylindrical and spherical symmetry. Acta Cienc Indica-Phys 2004, 30(4), 371-6.

The similarity solutions for the three cases of plane, cylindrical and spherical symmetry are obtained. The shock is assumed to be strong.

4 tables, 9 ref

014296   Dhingra S;Arora S;George P J (Instrumentation Dep, USIC, Kurukshetra University, Kurukshetra) : Study of copper-silicaon junctions fabricated by selective electroless deposition. Indian J pure appl Phys 2004, 42(12), 916-20.

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

4 llus, 16 ref

014295   Dash S K;Panda S;Patnaik C U S (Physics Dep, P.N. College, Khurda-752 057) : Analytical approximations of propagation constant of fundamental vector mode for power law profile fibre. Ultra Scient phys Sci 2004, 16(3), 373-80.

The concept of mode is very important in the study of propagation of electromagnetic waves through an optical fibre. Various approximation methods viz. the WKB method, the perturbation method and the variation method have been used to obtain the solutions of the scalar wave equation. The variational method has been shown to give highly accurate results in computing the propagation characteristics of graded index fibers. Further, this method gives closed form `expression for tlne modal field and hence can be used to calculate spice loss, microbending loss etc.. Used the scalar modal field obtained from the variational method to calculate vector propagation constant of single mode fibers.

1 table, 9 ref

014294   Cinta Pinzaru S;Pavel I;Peica N;Leopold N (Physics Dep, Babes-Bolyai Univ, Kogalniceanu No. 1, Cluj-Napoca 3400, Romimia) : Concentration dependence Raman and SERS spectra of E 102 food additive. Asian Chem Lett 2004, 8(1), 39-43.

E 102 food additive is characterised by means of FT-Raman, micro-Raman and SERS spectroscopy in Order to check the detection limit for monitoring the dye content in food. The dye presence was detectable under nanomole level using SERS on silver colloid.

3 illus, 9 ref

014293   Chaturvedi A;Singh M P (Computer Science Dep, Institute of Basic Science, Khandari, Dr. B.R. Ambedkar Univ, Agra) : Neural networks pattern classification for certainty in measurement of position and momentum with Heisenberg uncertainty principle. Acta Cienc Indica-Phys 2004, 30(3), 263-70.

Heisenberg uncertainty principle can be discussed by using the pattern classification technique Artificial Neural Networks with Back-propagation learning rule. In this process a suitable arrangement can be constructed that contains the control of two experiments, one of which is designed to measure the position and other one is desiged to measure the momentum of a in sub-atomic particle (the electron). The control system will determine either the position or momentum of electron, which less uncertain for any wavelength of light at any instant and start measuring the less uncertain quantity with the corresponding experiment.

2 illus, 19 ref

014292   Chandrasekaran J;Jina Devi H;Swamy N V C; Nagendra H R (NO, Swami Vivekananda Yoga Anusandhana Samsthana, 19, Gavipuram Circle, Kempegowda Nagar, Bangalore-560 019) : Spectral analysis of Indian musical notes. Indian J Tradl Knowledge 2005, 4(2), 127-31.

In the paper, attempts made to study the spectral aspects of Indian musical notes, particularly the Carnatic music has been discussed. Recordings were made of the seven notes of the classical music using three male and three female voices. The analysis of the waveforms using the appropriate software yielded the energy, frequency and time spectra, helping in identifying the formants of the signals which in turn define the signatures of the sound pattern.

12 illus, 6 ref

014291   Bouchard M;Smith D C (Laboratoire de Mineralogie, Museum National d'Histoire Naturelle, 61 Rue Buffon, 75005 Paris, France, Email: mbouchar@mnhn.fr) : Evaluating Raman microscopy for the non-destructive archaeometry of corroded coins. A powerful technique for conservation studies. Asian Chem Lett 2004, 8(1), 21-37.

The mineral corrosion products on several antique to modem coins have been identified non-destructively by Raman Microscopy (RM) in order to obtain archaeometric data on the nature of the minerals present, and hence of the corrosion processes which created them, by taking advantage of the exceptional analytical potential of RM for restoration and conservation work. Fourteen coins incorporating one or more of the metals Ag, Al, Cu, Fe, Ni, Pb, Sn or Zn, were examined on a micrometric scale. The results demonstrate the facility with which various oxides, hydroxides, carbonates and chlorides, and especially composite salts thereof, may be identified.

6 illus, 1 table, 54 ref

014290   Bhagat S K (NO, , Vill-Baigana, P.O.-Ganeshpur, Purnea-854 301) : Analysis of fourier transforms of quasi-crystals. Acta Cienc Indica-Phys 2004, 30(4), 461-3.

Analysis of Fourier transform of quasi-crystals has been presented. For quasi-crystal diffraction, a more important factor would be the effect of the quasi-crystal itself other than regular crystal equivalent terms that give the transforms in a close form involving structure factor, quasilattice factor and kinematic factor. In addition to these author had the addition problem in the case of electron diffraction. The diffraction pattern has been already calculated from different finite segments of quasilatice having the same width and number of scatterers. The peak-positions have been numerical calculated starting from the positions where the peaks would occur in the diffraction from an ideal quasilattice with the smallest interval possible (10^-6) and then locating the maxima nearest to them. Although the width is the same, the peak positions have been found to shift which cannot be explained by the slit-function. This clearly indicates that the arrangement of scatterers plays a crucial role in determining the diffraction pattern. In the 2-dimensional case, though the real-space tiling is not circular, it has been pointed out that only scatters lying in the circular region were used in the Fourier transform calculations.

6 ref

014289   Benny P G;Shah M R;Bhatt B C;Sabharwal S (Radiation Technology Development Section, Bhabha Atomic Research Centre, Trombay, Mumbai-400 085, Email: bennypg@yahoo.com) : Absorbed dose distribution at a large scale gamma irradiator - a data analysis. Indian J pure appl Phys 2004, 42(12), 879-85.

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

4 illus, 18 ref

014288   Baskaran R;Selvakumaran T S;Subramanian V (Radiological Safety Div, Safety Group, Indira Gandhi Center for Atomic Research, Kalpakkam-603, , Email: rb@igcar.ernet.in) : Aerosol test facility for fast reactor safety studies. Indian J pure appl Phys 2004, 42(12), 873-8.

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

5 illus, 1 table, 17 ref

014287   Bakkialakshmi S;Shanthi B;Santhi R; Chandrakala D (Physics Dep, Annamalai University, Annamalai Nagar-608 002) : Fluorescence quenching spectra of p-chloranilne and p-toluidine. Indian J pure appl Phys 2004, 42(12), 937-9.

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

1 illus, 1 table, 13 ref

014286   Bakkialakshmi S;Shanthi B;Santhi R; Chandrakala D (Phys Dep, Annamalai University, Annamalai Nagar-608 002) : Fluorescent spectral studies of molecualr complexes. Acta Cienc Indica-Phys 2004, 30(4), 405-08.

An attempt has been made to obtain the fluorescence quenching spectra of p-anisidine using nitrobenzene and acetonitrile, as quenchers in 1,4-dioxane. The concentration of fluorescer solution was kept constant (0.01 m) in each experiment, by adding fixed aliquot of stock solutions prepared in the solvent. Quenchers (nitrobenzene and acetonitrile) in the respective solvent was added to the above solution in small volumes (0.1 to 0.5 ml) and the fluorescent intensities were measured. The stern-volmer constants for all quenching processes have been plotted. Regression analysis for stern-volmer plot has been carried out. Regression coefficient (r) and the stern-volmer constant (K_sv) were calculated. Stoke's shift, Lonization potentiala, Electron affinity and the solvent parameter (Z) have also been calculated.

2 illus, 2 tables, 8 ref

014285   Bakkialakshmi S;Shanthi B;Chandrakala D; Santhi R (Phys Dep, Annamalai Univ, Annamalai Nagar-608 002) : Quenching of p-toluidine bybenzoic acid and carbontetrachloride in benzene. Acta Cienc Indica-Phys 2004, 30(4), 401-4.

An attempt has been made to obtain the fluorescence quenching spectra of p-Toluidine using benzoic acid and carbon tetrachloride as quenchers in benzene. The concentration of fluorescer solution was kept constant (0.01 m) in each experiment, by adding fixed aliquot of stock solutions prepared in the solvent. Quenchers (benzoic acid and carbon tetrachloride) in the respective solvent was added to the above solution in small volumes (0.1 to 0.5 ml) and the fluorescent intensities were measured. The stern-volmer constants for all quenching processes have been plotted. Regression analysis for stern-volmer plot has been carried out. Regression coefficient (r) and the stern-volmer constant (K_sv) were calculated. Stoke's shift, Lonization potentiala, Electron affinity and the solvent parameter (Z) have also been calculated.

3 illus, 2 tables, 15 ref

014284   Baia L;Stefan R;Simon S (Physics Dep, Babes-Bolyai Univ, 3400 Cluj Napoca, Romania) : IR and Raman investigations of B₂O₃-Bi₂O₃-Fe₂O₃ glasses and glass ceramics. Asian Chem Lett 2003, 7(4), 171-6.

Infrared and Raman spectroscopic measurements have been performed in order to investigate the 90%[xB₂O₃(1-x)Bi₂O₃]10%Fe₂O₃ system with different Bi/B nominal ratios (0.07 ≤ x ≤ 0.625) and to obtain valuable information about the competitive role of component oxides in the formation of the glass network. The glass samples have been prepared by melting at 1100 °C and rapidly cooling at room temperature. In order to relax the structure, to improve the local order and to develop crystalline phases the glass samples have been kept at 575 °C for 10 hours. The influence of Fe₂O₃ on the B₂O₃ and Bi₂O₃ structures as well as the local order changes around the constituent atoms in as prepared and heat-treated samples have been studied.

4 illus, 19 ref

014283   Anand R K (Physics Dep, Allahabad Univ, Allahabad-211 003) : Effects of overtaking disturbances on the propagation of strong plane and cylindrical shock waves in magnetogasdynamics. Ultra Scient phys Sci 2004, 16(3), 391-8.

Effects of overtaking disturbances behind the flow, on the propagation of strong plane and cylindrical hydromagnetic shock waves through an ideal gas in presence of a magnetic field having all the three components (H_r0² = ηrH_zo², H²_θ = rH²_z0 and H_z0 = constant), have been included to improve the accuracy of CCW approximating technique. Assming an initial density distribution ρ₀ = ρ¹e^{λr, where ρ1 is the density at the axis of symmetry and λ is a non dimensionalising constant, the analytical expressions for flow variables have been deduced. It is shown that the applications of CCW approach and the neglect of overtaking disturbances are equivalent.}

18 ref

014282   Ali K (NO, National Institute for Standards (NIS), 4 Tersa Street, Giza 12211, Egypt, Email: khalid.ali@excite.com) : Determination of freezing point of copper relative to that of silver by radiation thermometer. MAPAN 2003, 18(4), 209-15.

The work aims to measure and define the thermodynamic temperature of copper freezing point relative to silver point. The work was carried out using NIS radiation thermometer of 900 nm effective wavelength. Measurements showed that the copper freezing point was 11 mK higher than its value stateed in the ITS-90. This also showed an agreement with the uncertainties of ±20 mK for silver and copper relative to gold point, as estimated by the Working Group 4 of the CCT.

5 illus, 1 table, 7 ref

013296   Will C M (Physics and McDonnell Center for the Space Sciences Dep, Washington University, St. Louis, MO-63130, USA, Email: cmw@wuphys.wustl.edu) : The confrontation between general relativity and experiment. Pramana J Phys 2004, 63(4), 731-40.

We review the experimental evidence for Einstein's general relativity. Tests of the Einstein equivalence principle support the postulates of curved space-time and bound variations of fundamental constants in space and time, while solar system experiments strongly confirm weak-field general relativity. The binary pulsar provides tests of gravitational wave damping and of strong-field general relativity. Future experiments, such as the gravity probe B gyroscope experiment, a satellite test of the equivalence principle, and tests of gravity at short distance to look for extra spatial dimensions could further constrain alternatives to general relativity. Laser Interferometric Gravitational Wave Observatories on Earth and in space may provide new tests of scalar-tensor gravity and graviton-mass theories via the properties of gravitational waves.

4 tables, 24 ref

013295   Verma K K;Soni K R (Department of Physics, Microwave Laboratory, Malaviya National institute of Technology, Jaipur-302 017) : Radiation characteristics of two-element of equilateral triangular patch microstrip antenna in plasma medium. Indian J Phys 2004, 78(12), 1359-64.

The far zone EM-mode and P-mode radiation fields are derived using vector wave function techniques and pattern multiplication approaches. An analytical study of a two-element array of equilateral triangular patch microstrip antenna is presented at a frequency of 10 GHz. The results are obtained both in plasma medium and in free space and compared with those of single-element triangular patch microstrip antenna. Some important antenna parameters such as radiation conductance, radiation efficiency, directivity and quality factor are plotted for different values of plasma to source frequency. It is observed that EM-mode field patterns are modified to a great extent, where as the P-mode field patterns show discrete ray-like structure similar to single element triangular patch microstrip antenna.

11 illus, 8 ref

013294   Venkatachalapathy R;Gournis D;Manoharan C; Dhanapandian S;Deenadayalan K (Dep of Physics (DDE), Annamalai University, Annamalainagar-608 002) : FTIR and Mossbauer spectroscopic studies of archaeological potteries from Nathikudi, Tamil Nadu. Indian J Phys 2004, 78(12), 1371-5.

Fourier Transform Infrared (FTIR) and room temperature Mossbauer spectra have been recorded for the recently excavated archaeological potteries from Nathikudi Tamil Nadu, India. The experimental results explore the technology involved in producing the archaeological artifacts for different purposes. During firing, the iron present in the clay materials undergoes characteristic change in its chemical and physical state, depending on the kiln atmosphere and the maximum firing temperature reached, which can be followed by using FTIR and Mossbauer spectroscopic techniques. From the above techniques, type of clay, firing temperature and firing atmosphere for the production of archaeological potteries were well established.

3 illus, 14 ref

013293   Trivedi S P (Theoretical Physics Dep, Tata Institute of Fundamental Research, Mumbai-400 005, Email: sandip@theory.tifr.res.in) : De Sitter universes and the emerging landscape in string theory. Pramana J Phys 2004, 63(4), 777-83.

We discuss a recent proposal to construct de Sitter vacua in string theory. It is based on flux compactifications in string theory where all the moduli are stabilised and supersymmetry is broken with control. The resulting picture is that of a complicated landscape with many vacua of widely varying values for the cosmological constant.

11 ref

013292   Tripathi G;Rai V K;Rai S B (Dep of Physics, Laser and Sperctroscopy Microwave Laboratory, Banaras Hindu Universit, Varanasi-221 005) : Overtone spectra of phenol derivatives. Indian J Phys 2004, 78(12), 1377-80.

Overtone spectra of 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol and 2,4,6-trichlorophenol have been analyzed in the 2500-14000 cm^-1 region. The vibrational frequencies and the anharmonicity constants for the C-H and O-H stretching vibrations have been evaluated. The effect of the substitution of chlorine atom at different positions of the phenol ring has been studied. The observations are well supported by theoretical calculations for the charge density and the bond lengths using molecular orbital AM1 method. The possibility of intramolecular hydrogen bonding involving O-H-C1 has also been marked in the case of 2-chlorophenol and 2,4-dichlorophenol. It is noted that in the case of 4-chlorophenol, the shift in C-H stretching frequency is proportional to the sum of the Hammett (σ) of the substituents while in the case of 2-chlorophenol it is only 55% of the value in 4-chlorophenol.

1 illus, 4 tables, 10 ref

013291   Thakur V C;Pandey A K (NO, Wadia Institute of Himalayan Geoloty, Dehra Dun-248 001) : Late quaternary tectonic evolution of dun in fault bend/propagated fold system, Garhwal sub-Himalaya. Curr Sci 2004, 87(11), 1567-76.

Two-distinct styles and amplitudes of folding occur in Dun. In the northern part, the overturned Santaurgarh anticline with both limbs dipping steep to moderate was developed as fault propagated fold over the Santaurgarh Thrust (ST). The uplifted hanging wall of the ST constituted the dissected Siwalik, and the down-faulted footwall formed the pedimented Siwalik. To the South in the frontal range, the Siwalik strata were folded into Mohand anticline as fault-bend fold over the Himalayan Frontal Thrust (HFT). The uplifted terraces on the fore-limb of the anticline resulted due to displacement on the HFT in Holocene. The Bhauwala Thrust, Majhaun Fault and Asan Fault were formed as out-of-sequence thrusts within the Main Boundary Thrust-HFT wedge of folded Siwalik and overlying Dun gravels subsequent to ST. Extrapolation of earlier published OSL age data and our observations suggest initiation of HFT between 500 and 100 Ka; the ST was initiated in post-500 Ka and continued to propagate till post-40 Ka. The Bhauwala Trust was developed between 29 and 20 Ka, and the Asan fault post-dated 10 Ka.

7 illus, 18 ref

013290   Tel E;Aydin A;Ubeyli M;Demirkol I (NO, Gazi University, Faculty of Arts and Science, 06500 Ankara, Turkey) : Investigation of the (n, 2n) reaction cross sections of some neighbouring nuclei with and without deformation. Indian J Phys 2004, 78(11), 1229-37.

The (n, 2n) reaction cross section calculations for some neighbouring target nuclei either with deformation or without deformation have been made for an incident energy range of 8 - 24 MeV. In these calculations, the geometry dependent hybrid model and the exciton model consisting of the effects of pre-equilibrium emissions have been used. The exciton model has also been used to investigate the pre-equilibrium direct effects. Furthermore, the experimentally measured cross sections taken from literature have been calculated using other empirical and the semi-empirical formulae for the incoming energies which satisfy the condition U_r = E_n+Q_n,2n = 6±1 MeV. The theoretical and experimental results for some neighbour target nuclei with or without deformation have been compared. The obtained results have been discussed with the available experimental data, and found to be good in agreement.

1 illus, 13 tables, 41 ref

013289   Singh V;Tripathi B V;Joshi D C (Physics Dep, H N B Garhwal University, Post Box 25, Srinagar (Garhwal)-246 174) : Euclidean space dyon solutions. Indian J pure appl Phys 2005, 43(3), 157-66.

Using a Cabbibo-Ferrari type non-Abelian field tensor, dyon solutions have been obtained in temporal gauge. Defining the Euclidean fields and imposing the conditions of self and anti-self duality, the obtained solutions have been shown to be the Euclidean space dyon solutions.

30 ref

013288   Singh V;Tiwari M;Dhoble S J (Physics Dep, Sadhu Vaswani College, Baiagarh, Bhopal-462 030) : On the emission and the excitation spectra of SrS:Cu, CaS:Sm and CaS:Dy,Ce phosphors. Indian J Phys 2004, 78(11), 1265-7.

Green phosphors based on SrS and CaS have been developed for display applications. Suphide based lamp phosphors activated with Cu, Sm, Dy and Ce were prepared by using solid-state diffusion method. Emission and excitation spectra of SrS:Cu, CaS:Sm and CaS:Dy,Ce phosphors were recorded at room temperature with the aim of their photoluminescence characterization. Their application as green emitting phosphors is discussed.

3 illus, 1 table, 15 ref

013287   Singh R;Srinivas Y S S;Khilar P;Kadia B;Dani S;Bora D (NO, Institute for Plasma Research, Bhat, Gandhinagar-382 428, Email: raghuraj@ipr.res.in) : Development of 20 kW amplifer at very high frequency (VHF). Indian J Radio Space Phys 2004, 33(4), 267-77.

A triode based 20 kW cw (continuous wave) amplifier has been developed and tested indigenously at 91.2 MHz and 70 MHz. The equipment will drive the pre-driver stage of 200 kW, which will, in turn drive the final stage of 1.5 MW of rf power to heat plasma in SST-1 Tokamak for 1000s. Various aspects of design and fabrication of the amplifier are discussed.

17 illus, 4 tables, 5 ref

013286   Singh D P;Singh U P (Physics Dep, F G M Goverment College, Adampur-125 052) : Diffusion coefficient and wave amplification determination from pitch angle dependent kinetic energy of electrons. Indian J Radio Space Phys 2004, 33(4), 234-40.

A new expression for diffusion coefficient D(α) is derived, which is a function of pitch angle (α) dependent kinetic energy of electrons. Pitch angle diffusion of electrons along with amplification of interacting VLF signals is studied at L=5.1. Diffusion coefficient D(α) has been found to increase but temporal wave growth (r) and power gain (in dB) decrease with increase in pitch angle. The derived expresession for D(r) is found to be convenient for numerical analysis. The results are interpreted in the light of observation/analysis of transmitted signals by Sonwalkar et al. The non-observation of 2.55-2.9 kHz signals is attributed to scarcity of suitable pitch angle anisotropy, A(E_rD>).

4 illus, 2 tables, 37 ref

013285   Singh C P;Chauhan R S (Physics Dep, R.B.S. College, Agra-282 002) : Analysis of thermala expansivity fo alkali halide crystals. Indian J Phys 2004, 78(11), 1215-9.

The temperature dependence of thermal expansivity and interionic separations have been studied for eight alkali halide crystals viz., NaF, NaCl, KCl, KBr, Kl, RbCl, RhBr and Rbl. The expression for interionic separation obtained carlier by Kumar has been corrected so as to make it compatible with the value of thermal expansivity at inital temperature. The values of interionic separation as a function of temperature calculated using the modified formulation are found to present close agreement with the experimental data for the alkali halides upto their melting temperatures.

4 illus, 21 ref

013284   Shrivastava J;Tiwari M S (Physics Dep, Dr H S our University, Sagar-470 003) : Alfven wave in the presence of parallel electric field in the magnetospheric plasma. Indian J Radio Space Phys 2005, 34(1), 17-22.

The effect of upward parallel electric field observed along the auroral field lines on the Alfven wave model of magnetosphere-ionosphere coupling is examined through the modification of the particle thermal velocity parallel to ambient magnetic field. Effects of electron beam generated in the plasma-sheet region and impinging the ionosphere, and temperature anisotropy of the acceleration region have been also considered. The enhancement of the auroral upward field-aligned current in the region of parallel electric field is predicted as observed by S3-3 satellite and polar satellite data.

6 illus, 43 ref

013283   Shibata M (NO, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan, Email: shibata@provence.c.u-tokyo.ac.jp) : Status of numerical relativity. Pramana J Phys 2004, 63(4), 703-15.

I describe the current status of numerical relativity from my personal point of view. Here, I focus mainly on explaining the numerical implementations necessary for simulating general relativistic phenomena such as the merger of compact binaries and stellar collapse, emphasizing the well-developed current status of such implementations that enable simulations for several astrophysical phenomena. SOME of our latest results for simulation of binary neutron star mergers are briefly presented.

3 illus, 58 ref

013282   Shengule D R;Jadhav K M;Bichile G K (Physics Dep, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad-431 004) : Magnetic ordering in a Zn-substituted Co-Mn-Fe-O ferrite system. Indian J Phys 2004, 78(11), 1221-4.

The structural and bulk magnetic properties of Zn-substitute Co_1.5-xZn_xMn_0.5FeO₄ (x = 0.0 - 0.6) ferrite system are studied using X-ray diffraction, magnetization and a.c. susceptibility measurements. The X-ray intensity calculations indicate that Mn⁴⁺, Co²⁺ occupy only B-sites, Zn²⁺ have strong preference for A-site and Fe³⁺ ions distributed among A and B-sites. The magnetization measurements exhiits a significant canting on the B-site which is satisfactorily explained on the basis of the non-collinear spin model of uniform canting. The a.c. susceptibility indicates that system orders into a cluster spin glass state with the magnetic moment of the cluster randomly frozen.

4 illus, 2 tables, 18 ref

013281   Sharma S D;Cassani E;Mordacchini C;Mantovani R;Novario R;Conte L;Bhatt B C (Dipartimento di Scienze Cliniche e Biologiche, Cattedra di Fisica Medi, Universita degli, Studi dell' Insubria, 21100 Varese, Italy, Email: sdsharma_barc@rediffmail.com) : Tongue and groove effect of varian multileaf collimator for different clinical conditions. J med Phys 2004, 29(2), 48-54.

Use of multileaf collimator (MLC) for shaping the treatment fields in external beam therapy is now a common practice. Tongue and groove arrangement is used in all commercially available multileaf collimators to limit interleaf leakage. The tongue and groove effect (TGE) is an under-dosing effect in the region of overlap between two adjacent leaves of a multileaf collimator. Mean dose reduction (MDR) and its spatial extent (in terms of FWHM) at the field junctions defined by Varian Standard 80 leaves MLC for 6 and 18 MV photon beams were measured using radiographic and radiochromic films. Measured values of MDR and mean FWHM are presented for three different field geometries, namely, a narrow field, a medium size rectangular field and an irregular field at the depth of dose maximum (d_m) as well as at 10 cm depth. These three fields correspond to the treatment fields used in intensity modulated radiotherapy (IMRT) and conformal/conventional radiotherapy. FWHMs are found to be independent of beam energy, depth of measurement and field geometry. However, MDR depends on beam energy, depth of measurement and field geometry. Maximum dose reduction of 17.6% with spatial extent of 2.8 mm was observed at the d_m of 6 MV photon beam for the narrow field.

7 illus, 5 tables, 5 ref

013280   Sharma R C;Sunil;Bharti P K (Mathematics Dep, Himachal Pradesh University, Summer Hill, Shimla (H.P.)-171 005) : Stability of superposed viscoelastic (Walters' B')- Newtonian fluids in porous medium. Proc Natn Acad Sci India-Sect A 2004, 74(Pt III), 311-22.

The Rayleigh-Taylor instability of a Newtonian viscous fluid overlying Walters' (model B') viscoelastic fluid is considered. For the stable configuration, the system is found to be stable or unstable if v₁'<60>or<62> k₁/εα₁ .The system is found to be unstable in the potentially unstable case. The variable horizontal magnetic field is also considered. For the stable configuration, in the hydromagnetic case also, the system is found to be stable or unstable if v₁'<60> or <62> k₁/εα₁ For the unstable configuration, the system is unstable for the wave-number band k <60> k^* or if v₁' <62> k₁/εα₁. The magnetic field has stabilizing effect and completely stabilizes the wave number band k <62> k^* if v'₁ <60> k₁/εα₁. This is in contrast to the stability of Newtonian superposed fluids in porous medium, where the system is always stable for the stable configuration.

8 ref

013279   Shanta A;Palaniselvam T;Vandana S;Banerjee M; Tripathi U B;Bhatt B C (Radiological Physics and Advisory Div, Bhabha Atomic Research Centre, CT & CRS Building, Anushaktinagar Mumbai-400 094) : Dosimetry of new <. J med Phys 2004, 29(2), 69-76.

The ¹³⁷Cs Intracavitary Kit, supplied by Board of Radiation and Isotope Technology (BRIT), is in clinical use for over two decades. Recently, BRIT has modified the design of the ¹³⁷Cs sources, This paper gives the dosimetry data for the new type of ¹³⁷Cs sources has been given. The dose rate constant, which is the dose rate, in tissue, at 1 cm on the transverse axis along the centre of the active source, worked out to be 0.934 cGy.h^-1.cm².U^-1 for the CSA-1 type source of active length 1.5 cm and 1.012 cGy.h^-1.cm².U^-1 for CSA-2 type source of active length 1.0 cm. The dose rate constant evaluated using Monte Carlo simulation (MCNP code version 3.1) agrees within 1 %. The dose rate constant measured using TLD and perspex phantom yielded a value of 0.927 cGy.h^-1.cm².U^-1 for CSA-1 type source and 1.053 cGy.h^-1.cm².U^-1 for CSA-2 type source, which are well within the uncertainty of measurement. Dose contributions at points A and B, as defined in the Manchester system of dosimetry, have been worked out for standard loadings.

5 illus, 5 tables, 7 ref

013278   sethu Raman M;Amirthaganesan G (Dep of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore-641 020, Email: sethu_muthu2003@yahoo.co.in) : Ultrasonic study of intermolecular association through hydrogen bonding in aqueous solutions of D-mannitol. Indian J Phys 2004, 78(12), 1329-33.

The density and ultrasonic velocity measurements were carried out in aqueous solutions of D-mannitol in the concentration range of 0.1-1.0 m between 303.15 K and 323.15 K with 5 K increments. Using the measured values of density (ρ) and ultrasonic velocity (u), other acoustical parameters such as adiabatic compressibility (β_ad), acoustic impedance (Z), hydration number (H_n) and intermolecular free length (L_f) were evaluated. These parameters were interpreted as due to the formation of intermolecular hydrogen bonding between the hydroxyl groups of D-mannitol and water molecules.

2 illus, 1 table, 20 ref

013277   Sengwa R J;Abhilasha;Mehrotra S C;Sharma B R (Physics Dep, Microwave Research Laboratory, J N V University, Jodhpur-342 005, Email: rjsengwa@rediffmail.com) : A comparative dielectiric study of poly(vinyl pyrrolidone) in unlike hydroxyl group number containing polar solveants. Indian J Phys 2004, 78(12), 1341-8.

Time Domain Reflectometry (TDR) technique has been employed to explore the dielectric behaviour of different concentration binary mixtures of poly(vinyl pyrrolidone) (PVP) with ethyl alcohol, ethylene glycol, poly(ethylene glycol) (PEG) and glycerol in the frequency range of 10 MHz - 10 GHz at 25°C. The frequency-dependent measured values of dielectric permittivity ε' and dielectric loss ε'' of these binary mixtures were fitted to the Havriliak-Negami expression. It is found that PVP-ethyl alcohol mixtures exhibit Debye type dielectric dispersion whereas the complex dielectric behaviour of PVP-ethylene glycol, PVP-PEG and PVP-glycerol mixtures can be represented by Cole-Davidson dielectric relaxation model. The values of static dielectric constant ε₀, high frequency limiting dielectric constant ε∞, relaxation time τ rand distribution parameters α and β of these systems were determined. The types of the formation of homogeneous and heterogeneous cooperative domains in the mixtures due to complexation between hydroxyl group/s of polar solvent with the carbonyl groups of PVP molecular chain, were discussed using the comparative values of evaluated dielectric parameters. Schematic diagrams of the structures of a complexation between PVP and self-associated polar solvents were proposed and their dynamics have been explored in view of their applications in drug control release systems.

5 illus, 1 table, 25 ref

013276   Sen Gupta A;Howe D A (National Physical Laboratory, , New Delhi) : Low-noise, high resolution microwave synthesis for atomic frequency standards. Indian J pure appl Phys 2005, 43(3), 221-7.

The performance of newer generations of ultra high stability atomic frequency standards based on laser cooled atoms and ions appears to be limited by the local oscillator and the microwave synthesis chain. To improve this performance, the design considerations of microwave synthesizers for Cs hyperfne clock transition at 9.192 GHz that emphasize high resolution, low phase modulation (PM) and amplitude modulation (AM) noise, low spurs near the carrier, and very high phase stability with respect to environmental effects have been studied. Typical performance achieved are: internal fractional frequency stability of 1.5 x 10^-15 at 10 s and 1 x 10^-18 at 1 day; fractional frequency step of 2 x 10^-17 and temperature coefficient less than 0.1-0.5 ps/K. The design is quite general and enables generation of microwave outputs corresponding to several different atomic transitions. The phase locking of the synthesizer to a high stability external frequency reference based on a cavity stabilized oscillator has been studied.

8 illus, 30 ref

013275   Saxena M (Applied Sciences & Humanities, Moradabad Institute of Technology, Ramganga Vihar - Phase II, Moradabad-244 001) : Crystallization kinetics and activation energy for crystal growth in Te_x(Bi₂Se₃)_1-x chalcogenide glasses. Indian J Phys 2004, 78(11), 1261-3.

The activation energy plays a dominant role in deciding the utility of the material for the specific purpose - here optical storage. Crystallization studies are carried out under non-isothermal conditions with samples of Te_x(Bi-2Se3)_1-x [x = 0.05, 0.1,0.2,0.3] chalcogenide glasses heated at several uniform rates. The dependence of the crystalline temperature (T_x) and the peak temperature of crystallization (T_p) on the composition and heating rate (β) has been studied. From the heating rate dependence of T_p, the activation energy for crystallization (E_c) has been evaluated. The results are discussed on the basis of Kissinger's approoach and Marseglia's theory for non-isothermal crystallization. This analysis helps in finding the suitability of an alloy to be used in phase transition optical memories/switches.

4 illus, 1 table, 9 ref

013274   Sathiyan S;Ravikumar M;Ravichandran R (Radiation Physics Dep, Kidwai Memorial Institute of Oncology, Hosur Road, Bangalore-560 029, Email: ssathiyan@hotmail.com) : Analysis of clinical teletherapy gamma beams from radiotherapy machines. J med Phys 2004, 29(2), 55-60.

The mega voltage photons interacting with the patient results in the production of scattered photons, secondary electrons and neutrons. These secondary particles lead in the deterioration of primary beam to a certain extent in terms of radiation flux and energy and it is relevant for radiation protection considerations of the patient during treatment. In this study an experimental method was used to estimate the quantum of flux due to primary and secondary photons, as well as recoil electron from the telecobalt beams by introduction of various intervening materials. The components of the Cobalt-60 output beam at different distances from the source position were studied in detail. At 50 cm distance from the source position, the recoil electron flux contribution is 13.8 %, 5.1 % and 4.7 % for depleted Uranium, tungsten and lead collimators respectively. At 80 cm distance the recoil electron contributes less than 2 % of the total flux. The effect of introduction of 5 mm Perspex plate in the beam will increase the flux of the recoil electron from 5.1 % to 17 % at 50 cm distance from the source and it is insignificant beyond 80 cm. The recoil electron contribution is significantly less in tele Caesium beam compared to telecobalt beam. The outcome of the study helps in taking appropriate measures to reduce the less penetrating components in the useful beam.

5 illus, 3 tables, 7 ref

013273   Sasaki M (NO, Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan, Email: misao@yukawa.kyoto-u.ac.jp) : Brane-world cosmology and inflation. Pramana J Phys 2004, 63(4), 785-96.

There has been substantial progress in brane-world cosmology in recent years. Much attention has been particularly paid to the second Randall-Sundrum (RS2) scenario in which a single positive-tension brane is embedded in a five-dimensional space-time, called the bulk, with a negative cosmological constant. This brane-world scenario is quite attractive because of the non-trivial geometry in the bulk and because it successfully gives four-dimensional general relativity in the low energy limit. After reviewing basic features of the RS2 scenario, we consider a brane-world inflation model driven by the dynamics of a scalar field living in the five-dimensional bulk, the so-called bulk inflaton model. An intriguing feature of this model is that the projection of the bulk inflaton on the brane behaves just like an ordinary inflaton in four dimensions in the low energy regime, H²l² << 1, where H is the Hubble expansion rate of the brane and l is the curvature radius of the bulk. We then discuss the cosmological perturbation on superhorizon scales in this model. We find that, even under the presence of spatial inhomogeneities, the model is indistinguishable from the standard four-dimensional inflation to O(H²l²). That is, the difference may appear only at O(H⁴t⁴).

2 illus, 34 ref

013272   Sarma A A L N;Vizayabhaskar V (Meteorology & Oceanography Dep, Andhra University, Visakhaptnam-530 003, Email: aalnsarma_met@rediffmail.com) : Interannual variability of precipitable water vapour-ENSO/LNSO signal. Indian J Radio Space Phys 2005, 34(1), 50-5.

Knowledge of the quantity of precipitable water vapour content (PWVC) in space and time over a region is of fundamental importance in hydro-meteorological studies. In the investigation using the radiosonde data for a 17-year period from 1984 to 2000, the mean monthly precipitable water for Visakhapatnam (lat.17°43'N, long.83°14'E) is evaluated for the layers surface to be 500 mbar. The inter-annual and intra-seasonal variation of precipitable water vapour and its relation to the mean monthly rainfall have been discussed. Seasonal cycles of precipitable water during ENSO (El Nino Southern Oscillation) and LNSO (La Nina Southern Oscillation) periods along with normal are reported. Cycling rates of moisture flux and percentage occurrence of rainfall from the corresponding amount of precipitable water vapour content have been dealt with.

4 illus, 2 tables, 9 ref

013271   Sahu D K;Khare P K;Srivastava R K (Physics Dep, Institute of Basic Sciences, Bundelkhand University, Jhansi-284 128) : Electrical transport in solution-grown thin films of polyvinylidene fluoride. Indian J pure appl Phys 2005, 43(3), 207-14.

The mechanism of electrical conduction in polyvinylidene fluoride (PVDF) films sandwiched between similar and dissimilar electrodes has been investigated in both transient and steady state conduction modes. The thin films are of 20μm thick and obtained by the isothermal immersion technique. The conduction process is examined in a temperature range 40-80°C, with applied dc electric fields ranging from 10 to 100 kV/cm using both types of similar and dissimilar electrodes systems. The nature of transient currents has mainly been attributed to the dipolar nature in the lower temperature region where slope value m is found to vary from 0.43 to 0.62 for similar electrode system and from 0.78 to 0.98 for dissimilar electrode combinations. The steady state conduction current has been found to be strongly temperature dependent. The current-voltage characteristics show two regions of conduction: ohmic conduction with a slope of curve 0.48 to 0.68 at lower and non-ohmic conduction with a slope 1.87 to 2.05 at higher fields. These results have been interpreted in the light of Richardson-Schottky alongwith space charge limited (SCL) conduction transport mechanism.

11 illus, 37 ref

013270   Sahu D K;Khare P K;Shrivastava R K (Physics Dep, Institute of Basic Science, Bundelkhand University, Jhansi-284 128) : Dielectric loss factor in electrically polarized polyvinylidene fluoride film electrets by TSDC. Indian J Phys 2004, 78(11), 1205-9.

Thermally stimulated discharge current (TSDC) in film of polyvinylidene fluoride (PVDF) was measured under various polarizing condition. The TSDC thermograms were recorded by reheating the samples at a rate of 3°C/min. It was found that samples give rise to a peak around (100±10°C). The peak position is not consistent with the polarization fields and temperatures. The activation energy associated with the peak is found to be 0.62 eV. The dependence of TSD current and TSDC data on polarizing agents, i.e. field and temperature is explained on the basis of theoretical predictions. It can be considered that space charge polarization contributes significantly to the polarization of the polymer. The decrease in loss factor with increasing frequency can also be understood on the basis of space charge polarization. The dielectric loss factor has been evaluated and its variation with the angular frequency and forming polarization field (Ep) is reported.

4 illus, 20 ref