010128   Ramakrishna Murthy M;Venkateshwar Rao E (Physics Dep, University College, Kakatiya Univ, Warangal-506 009, Email: dr_evr@yahoo.com) : Studies on ion-beam modification of ADP and KDP crystal surfaces. Indian J Phys 2010, 84(2), 193-8.

Experimental investigations on He⁺ ion (150 keV) beam modifications of the (100) surfaces of ADP and KDP single crystals, relative to asgrown surfaces have been made, to assess the nature and extent of radiation damage. Studies on the surface micromorphology, defect substructure, defect concentration, surface conductivity and microhardness have been made. Studies on chemical etching in both ion irradiated and asgrown surfaces revealed drastic changes in etchpit morphology and defect concentration. Measurement of surface electrical conductivity, employing four-point probe method, showed enhancement in conductivity at all the temperatures of observation which is attributed to enhanced proton migration. Measurement of microhardness and studies on planar plastic anisotropy in asgrown surfaces relative to ion bombarded surfaces have been made employing Knoop indenter and the results are interpreted in terms of the nature of bonding, bond strength and radiation damage on ion bombardment. Plastic anisotropy in these surfaces is found to be in conformity with the (100) plane on which the indentations were made.

4 illus, 12 ref

010127   Raizada A;Santosh Kumar;Khare S (P.G. Studies and Research in Physics and Electronics Dep, R. D. Univ, Jabalpur-482 001, Email: amita_raizada@rediffmail.com) : Dependence of successive GMSs with Dst <60> - 100 n T on solar and interplanetary parameters. Indian J Phys 2010, 84(2), 183-92.

The intense Geomagnetic Storms (GMSs) with Dst <60> -100 nT have been investigated for the period from Jan 1996 to Dec 2006. Seven GMSs of doublet and four of triplet nature are observed. Firstly, each GMS has been studied separately as if they are associated with independent Coronal Mass Ejections (CMEs). Secondly, for each doublet and triplet, the accumulated effect on GMS has been investigated and correlated with Dst index so as to understand the geoeffectiveness of Successive Intense GMSs. Majority of the successive intense GMSs have occurred during maximum phase of Solar cycle. During the occurrence of overlapping successive storms Dst falls abruptly. For non-overlapping successive storms, the Dst value falls gradually to minimum, showing a trend of recovery before the geosphere is hit by another storm. It is observed that the combined effect on GMSs is due to the Solar Wind (SW) being complex, having a very high value of SW velocity (Vsw) continuously for a very long period of 2 to 6 days. Further, Bz falls to a much lower value and B rises to a pretty high value for accumulated effect than for isolated GMS. When the GMSs are considered as separate entity, the correlation coefficient of Interplanetary Magnetic Field (IMF) parameters B and Bz and further, their products Vsw.B and Vsw.Bz correlated with Dst index are found to be -0.65, 0.72, -0.66 and 0.77 respectively; whereas, the coefficients are much better with the respective values of-0.7, 0.87, -0.78 and 0.90, for the accumulated effect of GMSs. Thus, it is preferable to investigate the accumulated effect of CMEs causing successive GMSs as compared to their isolated effects.

5 illus, 2 tables, 22 ref

010126   Raghuwanshi S K (Electronics and Communicatio Dep, Sir Padampat Singhania Univ, Bhatewar, Tehsil Vallabhnagar, Udaipur-313 601, Email: sanjeevrus@yahoo.com) : Comparative study of asymmetric versus symmetric planar slab dielectric optical waveguides. Indian J Phys 2010, 84(7), 831-46.

Studied the asymmetric versus symmetric planar waveguide in terms of their usefulness in optical fiber communication systems. We have explored the thin waveguide versus thick waveguide first. Later on usefulness of asymmetric versus symmetric waveguide is carried out to target for WDM optical network application. All kinds of optical network components are fabricated on Si substrate with the point of view of their application. Here asymmetric planar structure may be more useful compared to symmetric waveguide in terms of their non-uniform power confinement properties. However, the symmetric waveguide structure may be more useful for their high power confinement properties. It is well known that the thin symmetric waveguide supports at least one mode. However the thick waveguide may support many even as well as odd modes. We study the power confinement properties for symmetric as well as asymmetric waveguide structure. We conclude that higher order modes show the nonlinear power variations. Mode field profile for various cases is discussed as well. Comparative study between asymmetric versus symmetric waveguide has a lot of significance in optical network area. It has been shown through analysis that in asymmetric waveguide, the power flows more through film region in the case of fundamental mode. Power confinement properties for asymmetric waveguide versus symmetric waveguide have been studied.

13 illus, 21 ref

010125   Purushotham E;Gopi Krishna N (Physics Dep, Kakatiya Univ, Warangal-506 009, Email: nallacheruvu_gopi@yahoo.com) : Effect of lattice strain on the debye-waller factors of Mg, Zn and Cd. Indian J Phys 2010, 84(7), 887-93.

Lattice strains in Mg, Zn and Cd powders produced by grinding have been analyzed by X-ray powder diffraction. The lattice strain (ε) and Debye-Waller factor (B) are determined from the half-widths and integrated intensities of the Bragg reflections. In all three cases viz. Mg, Zn and Cd, the Debye-Waller factor is found to increase with the lattice strain. From the correlation between the strain and effective Debye-Waller factor, the Debye-Waller factors for zero strain have been estimated for Mg, Zn and Cd. The variation of energy of vacancy formation as a function of lattice strain has been studied.

2 illus, 1 table, 16 ref

010124   Prasad D S V V D;Prasad S N V S;Vara Prasad J;Latha Devi N S M P;Rama Rao P V S (Physics Dep, Andhra Univ, Visakapatnam-530 003, Email: dsvvdprasad@yahoo.com) : Diurnal and seasonal variations in h'F and foF2 over low (Indian) and mid (Japanese) latitude stations-a comparative study. Indian J Phys 2010, 84(4), 345-58.

Using the simultaneous data of ionosonde from a low latitude station, Waltair, India (17.7°N,83.3°E) in the Indian sector and a mid latitude station, Kokubunji, Japan (35.7°N,139,5°E) in the Japanese sector during the high sunspot year of 2001, a comparative study of the variations in the diurnal, seasonal and day to day characteristics of the ionospheric F-region parameters, such as the virtual height of the F-layer (h'F) and the critical frequency of the F₂ layer (foF2), are studied. The effect of geomagnetic activity variations of the F-region parameters over the low and mid latitude stations is also presented.

8 illus, 7 ref

010123   Pandey R K;Tripathi D N (Synod Higher Secondary School, Mision Vengthlang, Aizawal-796 005, Email: drrakesh0107@yahoo.co.in) : Comparison of structure factors and pair correlation functions obtained using coulomb attractive potential and screened coulomb potential for the suspended macroions. Indian J Phys 2010, 84(4), 397-404.

The structure factors and pair correlation functions have been calculated for the macroions suspended in water using coulomb attractive potential (CAP) and the results have been compared well with the results obtained from the RMSA and MMSA using screened coulomb potential (SCP). Differences among the values of compressibility in the limit of zero momentum transfer, excess energy per macroion and coordination number for both the potentials have been reported. Liquid like ordering of the FCC type has been obtained using both CAP as well as SCP potentials between suspended macroions.

2 illus, 1 table, 33 ref

010122   Panda P K;Das B P (Raman Center for Atomic, Molecular and Optical Sciences, Indian Association for the Cultivatio, Jadavpur, Kolkata-700 032, Email: prafulla.k.panda@gmail.com) : Nuclear structure effects in parity non-conservation in heavy ions. Indian J Phys 2010, 84(7), 817-29.

Calculates the binding energy, charge radii in ¹²⁹Ba-¹⁴³Ba and ²¹⁴Ra-²²⁸Ra using the relativistic mean field theory which includes scalar and vector mesons. Evaluated the nuclear structure corrections to the weak charges for a series of these isotopes using different parameters and estimate their uncertainty in the framework of this model. The results will have important implication for the ongoing and planned parity non-conservation experiments and atomic structure calculations on Ba⁺ and Ra⁺.

1 illus, 13 table, 31 ref

010121   Pakzad H R (Physics Dep, Islamic Azad Univ, Bojnourd Branch, Iran, Email: pakzad@bijnourdiau.ac.ir) : Modified Kp-burger and Kp-burger equations in coupled dusty plasmas with variable dust charge and non-isothermal ions. Indian J Phys 2010, 84(7), 867-79.

The modified Kodomtsev-Petviashvili-Burger (mKP-Burger) and Kodomtsev-Petviashvili-Burger equations are derived in strongly coupled dusty plasmas containing non-isothermal ions, Boltzmann distributed electrons and variable dust charge. We use reductive perturbation method and discuss on solitary waves and shock waves solutions of these equations.

27 ref

010120   Nath P P;Joarder R N (Physics Dep, Jadavpur Univ, Kolkata-700 032) : Ordering potetial : the anomalous structure and properties of liquid KPb alloy. Indian J Phys 2010, 84(2), 125-32.

The anomalous structure and related properties of liquid KPb alloy are presented through an ab initio evaluated ordering potential as a function of concentration. It appears that considerable ordering occurs and it maximizes at the stoichiometric composition (c_k<126>0.5). We then use the model to obtain the Bhatia-Thornton(BT) structure factors at different compositions (c_k=0.1,0.3,0.5 and 0.8). The calculations of concentration fluctuation and other related thermodynamic properties show that this ordering potential approach works reasonably for this compound forming liquid alloy.

4 illus, 13 ref

010119   More P S;Khambayat H R;Ghuge C S;Shelke A V; Borwar S S;Chaudhari M A (Physics Dep, Novel Material Research Laboratory, Government Vidarbha Institute of Science and Humanities, Amaravati-444 604, Email: p_smore@yahoo.co.in) : Influenced of leaf moisture on transportation in porous silicon. Vidarbha J Sci 2010, 5(3-4), 69-73.

A miniaturized, non destructive, non toxic porous silicon (PS) based sensor is investigated as a sensing material to detect leaf moisture sensing with very low moisture concentration The Porous silicon layer (pore size =10 nm) is obtained by electrochemical of an p-type silicon wafer, was catalyzed by PEO to obtain the selective sensing of leaf moisture. We found that PEO based porous silicon appreciably detected the response leaf moisture with colour variation of leaf.

4 illus, 4 ref

010118   Midya S K;Sarkar H;Dey S S;Maitra A;Ghosh M (Atmospheric Sciences Dep, Calcutta Univ, Kolkata-700 019, Email: drskm06@yahoo.co.in) : Sharp depletion of attenuation of 22.235 GHz associated with Nor'wester over Kolkata, India and possible method of forecasting Nor'wester. Indian J Phys 2010, 84(4), 377-81.

The sharp depletion of attenuation of 22.235 GHz signal before the onset of Nor'wester over Kolkata, India is observed and possible explanation of such type of variation is presented. It is concluded that this may be taken as one possible method of forecasting severe thunderstorm associated with Nor'wester. Physical explanations based on the formation and dissipation mechanisms of thunderstorm are also presented.

4 illus, 3 ref

010117   Liakath Ali Khan F;Asghar J;Aravinthraj M (Physics Dep, Islamiah College, Vaniyambadi, Tamil Nadu) : Dielectric relaxation studies of 1:1 complexes of alkyl methacrylate with phenols derivatives. Rasayan J Chem 2010, 3(4), 766-71.

Dielectric absorption studies of H-bonded complexes of methyl methacrylate (MMA) and butyl methacrylate (BMA) with p-cresol, p-chlorophenol, 2,4-dichlorophenol and p-bromophenol have been studied at microwave frequency 9.37 GHz in dilute solution of carbon tetrachloride at 308K. Different dielectric parameters like dielectric constant ε' and dielectric loss ε" at microwave frequency, static dielectric constant ε₀ and dielectric constant ε ∞ at optical frequency have been determined. The validity of the single frequency equation of Higasi et al. for multiple relaxation time ι(1) is found to be function of the hydrogen bonding strength of phenolic hydrogen, whereas the group rotation relaxation time ι₍₂₎ is a function of the steric interaction of proton donor. The relaxation time is maximum at 50:50 mol% ratio.

9 tables, 20 ref

010116   Lal Ram;Oberoi C K;Upadhyay R G (Physics Dep, CSK Himachal Pradesh Krishi Vishwavidyalaya, Palampur-176 062) : Estimation of diquat from aqueous solution using inor-ganic gel membranes. Indian J envir Prot 2010, 30(1), 58-61.

Studies have been made on the use of zinc ferrocyanide and copper ferrocyanide gel membranes for estimating the concentration of diquat (1,1'-ethylene-2,2'-dipyridilum dibromide) in aqueous solution. The membranes can be used for estimating diquat in the concentration range of 3 x 10^-6 to 2 x 10^-4 M.

1 ilus, 1 table, 9 ref

010115   Karmakar M;Sarkar B;Azhruddin S;Mazumdar P S; Dorendrajit Singh S;Sambhunath Singh W;Bhattacharya M (Physics Dep, Acharya Prafulla Chandra College, New Barrackpur, Kolkata-700 131, Email: mahua_apc@yahoo.com) : On the temperature depedent frequency factor in thermoluminescence. Indian J Phys 2010, 84(5), 529-37.

In thermoluminescence (TL), frequency factor might not always be temperature independent. In the present article we consider a method of two heating rates for evaluation of temperature exponent for the case of temperature dependentfrequency factor in TL. The method has been analysed by applying it both to numerical and experimental TL peaks.

5 tables, 17 ref

010114   Karim A (Iqra Univ, Defence View, Shaheed-eMillat Road (Ext), Karachi, Pakistan, Email: akarimpk@iqra.edu.pk ) : Effect of stripe width on junction temperature of stripe-geometry semiconductor laser diodes. Indian J Phys 2010, 84(7), 795-801.

When laser diode (LD) is operated at high current densities, the junction temperature can rise significantly above the heat sink temperature. Generally, rise in junction temperature is a direct consequence of inability of different layers in a laser diode to dissipate heat efficiently due to finite thermal resistance. Usually, thermal resistance increases with a reduction in stripe width. Hence, the issue of thermal management becomes very important in modern days narrow stripe-geometry lasers. In this paper, the effect of stripe width on the junction temperature of a stripe-geometry semiconductor LD is analyzed by originating different heat sources. This has been accomplished using a simple technique for the measurement of junction temperature of a LD.

7 illus, 7 ref

010113   Karacoban B;Ozdemir L (Physics Dep, Sakarya Univ, 54187, Sakarya, Turkey, Email: lozdemir@sakarya.edu.tr) : Transition energies of neutral and singly ionized lanthanum. Indian J Phys 2010, 84(3), 223-30.

Calculated the transition energies (ionization potential, excitation energies, electron affinity) of neutral lanthanum (La l) and singly ionized lanthanum (La II). The calculations are based upon the multiconfiguration Hartree-Fock (MCHF) method within the framework of Breit-Pauli relativistic corrections. These energies are important for determination of physical and chemical properties for La I and La II. Results obtained have been compared with other works.

1 table, 31 ref

010112   Kalhor D;Zhairi R;Ketabi S A;Ebrahimzad A (School of Physics, Damghan University of Basic Sciences, Damghan, Iran) : Effect of Ag intermediate layer on crystalline, optical and electrical properties of nano-structured thin film. Indian J Phys 2010, 84(5), 539-46.

ITO thin films and ITO/Ag/ITO multilayered films were prepared on glass substrate by reactive thermal evaporation technique without intentionally heating the substrate. After deposition the films were annealed in air at three different temperatures (300°C, 420°C and 540°C). The thickness of each layer in the ITO/Ag/ITO films was kept constant at 50 nm/10 nm/40 nm. The opto-electrical and structural properties of ITO/Ag/ITO multilayered films were compared with conventional ITO single-layer films. Although both films had identical thickness, 100 nm, the ITO/Ag/ITO films showed a lower resistivity. XRD spectra showed that Ag intermediate layer had a small effect on crystalline properties of ITO/Ag/ITO films.

6 illus, 1 table, 28 ref

010111   K Xiang-jun;W Xin-qiang;L Gao-bin (College of Mathematics and Physics, Chongqing Univ, Chongqing-400 044, Email: kxj@cqu.edu.cn) : All-electron relativistic calculation on Au₅X (X=Sc, Ti, V, Cr, Mn, Co, Ni, and Zn) clusters. Indian J Phys 2010, 84(3), 245-56.

All-electron scalar relativistic calculations on Au₅X (X = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) clusters have been performed by using density functional theory with the generalized gradient approximation. Our calculation results indicate that all the lowest energy geometries of Au₅X clusters have planar structures; the doped X atoms prefer to occupy the fourfold coordination site. Except Au₅Fe, Au₆Co and Au₅Zn, for other clusters including pure Au₆ cluster, the HOMO are delocalized obviously with a contribution from all atoms in the cluster. On the contrary, the electron localization in Au₅Zn is very strong resulting in the least stability of this cluster. Au₅Cu cluster with six delocalized electrons being defined as magic number for two-dimensional system has the largest VIP and deepest HOMO energy level. With the substitution Au for X atoms, the metallicity of all Au₅X clusters is reinforced.

3 illus, 2 tables, 24 ref

010110   Joshi B C;Khulbey B;Upreti D;Dhaundiyal C C (Physics Dep, Kumaun Univ, (S. S. J. Campus), Almora-263 601, Email: bhawna_83ntl@yahoo.com) : Energy transfer Sm<. Indian J Phys 2010, 84(4), 405-12.

A study of energy transfer from samarium to erbium ions in zinc phosphate glass has been performed for a range of donor (1.0 wt% fixed) and acceptor concentrations ranging from 0.2 wt% to 1.2 wt%. The intensity of emission spectra of Sm³⁺ ions in the presence of Er³⁺ ions shows an overall decrease, thereby suggesting a non radiative energy transfer from Sm³⁺ ions to Er³⁺ ions. The interaction mechanism between the donor and acceptor ions is found to be mainly electric dipole-dipole in nature. The parameters required for the quantitative study of energy transfer e.g. energy transfer efficiencies, transfer probabilities, critical transfer distances have been computed.

5 illus, 1 table, 21 ref

010109   Jana P K;Saha I;Das P;Sarkar D;Midya S K (Chemistry Dep, Government College of Education, Banipur, North -24 Parganas, West Bengal-743 233) : Long-term ozone trend and its effect on night airglow intensity of Li 6708 °A at Ahmedabad (23°N, 72.5°E), India and Halley Bay (76°, 27°W), British Antarctic service station. Indian J Phys 2010, 84(1), 41-53.

A critical analysis has been made of the long-term yearly and seasonal variations of ozone concentration at Ahmedabad (23°N, 72.5°E), India and Halley Bay (76°S, 27°W), a British Antarctic Service Station. The effect of O₃ depletion on night airglow emission of Li 6708 A line at Ahmedabad and Halley Bay has been studied. Calculations based on chemical kinetics show that the airglow intensity of Li 6708 A line has also been affected due to the depletion of O₃ concentration. The nature of yearly variation and seasonal variation of intensity of Li 6708 A line for the above two stations have been shown and compared. It has been shown that the rate of decrease of intensity of Li 6708 A line was comparatively higher at Halley Bay due to dramatic decrease of Antarctic O₃ concentration.

7 illus, 3 tables, 25 ref

010108   Jana P K;Saha D K;Midya S K (Chemistry Dep, Government College of Education, Banipur, North- 24 Parganas-743 233, Email: pkjjngl@yahoo.co.in) : Effect of cloud on atmospheric ozone formation over Kolkata (22°34/N, 88 °24/E), India. Indian J Phys 2010, 84(4), 367-75.

The paper presents the nature of variations of clouds and total ozone over Kolkata (22°34'N, 88°24'E), India. The low-level cloud over Kolkata has been noticed to occur for many days and nights, particularly in the months from June to September. The low level cloud occurrences were minimum in winter months. The effect of cloud occurrence on ozone concentration has been critically analyzed and explained. It has been observed that the concentration of ozone increased with the increase of cloud occurrence. The related possible chemical explanation for ozone production processes has been offered.

4 illus, 26 ref

010107   Jana P J;Sarkar D;Saha I (Chemistry Dep, Government College of Education, Baipur, North 24-Parganas-743 233, Email: pkjjngli@yahoo.co.in) : Percentage contribution of ozone depleting substances on Antarctic ozone decline. Indian J Phys 2010, 84(5), 517-27.

A critical analysis has been made on contribution on ozone depleting substances (ODS) on the decline of ozone concentration at Antarctica. The nature of yearly variation of concentrations of ODS as well as of ozone has been presented. Possible mechanisms of ozone destruction processes catalyzed by ODS have also been offered.

6 illus, 22 ref

010106   Jain S K;Panda G;Vijay S K (Physics Dep, Govt. P.G. College, Bareli, Raisen-464 668, Email: skjain151166@yahoo.com ) : Variation in slab thickness of ionospheric F-region during earthquake by wavelet analysis. Indian J Phys 2010, 84(4), 359-65.

The present work deals with the anomalies in ionospheric slab thickness of F-region associated with strong seismic activity. In this regard we have considered ionosonde data of Critical frequency of F2 layer (foF2) and Ionospheric Total Electron Content (ITEC) observed for Athens [38°N, 24°E] and Rome [42°N, 13°E] stations. We have considered three cases of earthquake occurring on December 20, 2007, June 08, 2008 and April 06, 2009 and analyzed the ionosonde data of foF2 and ITEC for slab thickness of F-region of the ionosphere in one-hour interval time series record by filtering the geomagnetic disturbances. The result of the study shows that some unusual perturbations were observed in slab thickness of F-region for some days before the main seismic event. It may be due to the generation of seismogenic electric field above the surface of the earth well before the seismic event. This anomalous behavior of perturbations may be used as earthquake precursor.

6 illus, 1 table, 17 ref

010105   Islam R M (Physics Dep, Chittagong Univ, Chittagong-4331, Bangladesh, Email: islammohammed7@gmail.com) : Model for dimensional crossover temperature above the superconducting transition for high-temperature superconductors. Indian J Phys 2010, 84(1), 61-9.

Developed a theoretical model for the calculation of dimensional crossover temperature above the mean-field transition temperature using paraconductivity approach. We have numerically estimated the dimensional crossover (2D-3D and 2D-1D) temperature for the recently reported polycrystalline sample of the type Hg, TI-1223. Our numerical results indicate that the dimensional crossover temperature is a variable quantity and it depends on the parameter related to superconductivity and the range of temperature where the fluctuation effect is significant.

7 illus, 8 ref

010104   Hosseini A A;Taleshi F (Nanotechnology Laboratory, Physics Dep, Mazandaran Univ, Babolsar, 47416-95447, Iran, Email: hos-a-p1@umz.ac.ir) : Large diameter MWNTs growth on iron-sprayed catalyst by CCVD method under atmospheric pressure. Indian J Phys 2010, 84(7), 789-94.

In this work, authors have synthesized large diameter multi-walled carbon nanotubes (MWIMTs), by simple catalyst chemical vapor deposition (CCVD). Fe powder was spread on quartz substrate as a catalyst by a simple method and then heated under Ar atmosphere. Carbon's products can be synthesized by the decomposition of ethylene gas and deposition of carbon atoms on the Fe catalyst particles in Ar atmosphere at 930°C. XRD pattern, SEM and TEM images were used to investigate the characteristics, morphology and structure of carbon's products.

4 illus, 21 ref

010103   Goyal S L;Nawal Kishore (Applied Physics Dep, Guru Jambheshwar Science & Technology Univ, Hisar-125 001, Email: goyalsneh@yahoo.com) : Systematics of (n, α) reaction cross-sections at 14.5 MeV neutron energy. Indian J Phys 2010, 84(5), 553-62.

A comprehensive review of the experimental data for 14.5 MeV neutron induced reaction cross-sections for (n, α) reaction has been made for the isotopes having Z up to 82. Two different parameter groups have been considered by the classification of nuclei into odd-mass and even-even nuclei. The empirical formulae with two parameters for the evaluation of (η, α) reaction cross-sections are discussed in the present study. The odd-even effects have been observed as the cross-sections of odd-mass nuclei are higher as compared to their neighboring even-even nuclei. The shell effects have also been established at magic nucleon numbers for these reaction cross-sections.

4 illus, 22 ref

010102   Goswami A;Bezboruah T;Sarma K C (Instrumentation and USIC Dep, Gauhati Univ, Guwahati-781 014, Email: amarjyoti@gmail.com) : Embedded design for monitoring and controlling temperature. Indian J Phys 2010, 84(1), 71-9.

Each and every part of human life is somehow linked with the embedded products. Embedded systems are product of hardware and software co design. It is becoming an integral part of engineering design process for efficient analysis of data acquisition. Data acquisition implies the gathering of information about a system or process. It is the process of collecting data in an automated way from analog and digital sources of measurement, such as sensors and devices under test. The present paper describes the design of an embedded system for the control of temperature and light intensity in a single system using sensors, microcontroller and Liquid Crystal Display (LCD). It describes the controlling action incorporated in the hardware to control any device connected when specific conditions are met.

6 illus, 1 table, 11 ref

010101   Gorai S K;Mahto P (Physics Dep, Tata College, Chaibasa-833 201, Email: s_gorai@yahoo.com) : Plasmon energy bulk modulus, electronic polarisability of A<. Indian J Phys 2010, 84(5), 587-92.

A simple relation between the bulk modulus, plasmon energy, electronic polarisability are given for ternary chalcopyrite semiconductors. Bulk modulus has been evaluated from plasmon energy by proposing a linear relation between them. From bulk modulus electronic polarisability has been evaluated. The estimated values are in good agreement with the experimental values and earlier researchers.

2 tables, 41 ref

010100   Gopalakrishna G S;Mahesh M J;Ashamanjari K G; BhargavaRamu M S;Milina K (Studies in Geology (Crystal growth Laboratory) Dep, Mysor Univ, Manasagangotri, Mysore-570 006, Email: gopiganjam@yahoo.co.in) : Synthesis, thermal, magnetic and impedance characterization of Na₂ O-CoO-P₂O₅ crystalline materials. Indian J Phys 2010, 84(2), 143-50.

Na₂O-CoO-P₂O₅ materials were synthesized by soft hydrothermal technique at relatively low temperature and pressure conditions. These materials have shown positive correlation of crystallanity, size, thermal stability, magnetic properties and ionic conductivity with the concentration of Cobalt ions. Microstructures of the nano crystals were identified by taking the Scanning Electron Microscopy pictures. Thermal properties and minute structural variations of the prepared materials were investigated by DTA and FTIR studies. Magnetic results have revealed that these are frequency dependent prospective paramagnetic materials. A preliminary impedance analysis result indicates these are prospective solid electrolyte materials.

6 illus, 2 tables, 22 ref

010099   Gokula Nand;Kumar M (Physics Dep, G.B. Pant Agriculture and Technology Univ, Pantnagar-263 145, Email: joshigokulanand@yahoo.co.in) : Analysis of temperature dependence of thermal pressure of solids. Indian J Phys 2010, 84(4), 459-66.

Various models for determination of the temperature dependence of thermal pressure are critically examined in the light of experimental data. We have considered Mg₂SiO₄, Olivine, MgAI₂O₄, Pyrope rich garnet, Fe₂SiO₄, Grossular garnet, MnO, NaCI and KCI. The superiority of one model over others is discussed. The model is extended to study the compression behaviour at different temperatures, and the combined effect of pressure and temperature on thermal pressure of San Carlo Olivine. A good agreement obtained between theory and experiment demonstrates the validity of the present approach.

14 illus, 1 table, 24 ref

010098   Ghosh S;Dhara A;Purkait M;Mandal C R (Physics Dep, Jadavpur Univ, Kolkata-700 032, Email: mpurkait_2007@rediffmail.com) : Double charge transfer cross sections in collision of protons with helium atom. Indian J Phys 2010, 84(3), 231-43.

Theoretical total cross sections for the double charge transfer in proton-helium collisions are analysed using the four-body boundary corrected continuum intermediate state approximation in the energy range of 30 to 500 keV. We have also obtained differential double capture cross sections as a functions of projectile scattering angle. The intermediate continuum state of each.of the active electron has been taken into account in this formalism. Our calculated results are compared with the previous experimental and theoretical values. The agreement is very encouraging.

5 illus, 5 tables,43 ref

010097   Deosarkar S D;Jahagirdar H G;Talwatkar V B (NO, S. F. S. College, Nagpur, Maharashtra) : Acoustical studies of some pyrazoles in different percentage of dioxane-water mixture at 303. 15 K. Rasayan J Chem 2010, 3(4), 755-60.

The acoustical properties like adiabatic compressibility (β_s), apparent molal volume (φv), apparent molal compressibility (φK), intermolecular free length (L_f), specific acoustic impedance (Z) and relative association (RA) of some substituted pyrazoles viz. [5-(2-hydroxyphenyl)-3-(pyridin-3-yl)-4-(benzoyl)]-pyrazol, [5-(2-hydroxyphenyl)-3-(3-nitrophenyl)-4-(3-pyridinoyl)]-pyrazol, [5-(2-hydroxyphenyl)-3-(3-nitrophenyl)-(4-benzoyl)]-pyrazol and [5-(2-hydroxyphenyl)-3-(phenyl)-4-(3-pyridinoyl)]-pyrazol have been calculated from measured sound velocities (U) and densities (p) of their solutions of 0.01M concentrations in different percentage of dioxane-water mixture at 298.15 K. The variations in acoustical properties with increasing percentage of dioxane have been used to understand the changes in molecular interactions between water, dioxane and pyrazoles and to know the structure making and breaking property of solvent molecules on addition of dioxane in presence of pyrazoles.

8 illus, 20 ref

010096   Deo B B;Maharana L (Physics Dep, Utkal Univ, Bhubaneswar-751 004, Email: bdeo@iopb.res.in) : Gauge symmetry and supersymmetry in the higgsless standard model. Indian J Phys 2010, 84(7), 847-66.

The group SO(6) ⊗ SO(5) is shown to be the gauge group as well as supersymmetry group of a four dimensional superstring model. Here, we discuss how supersymmetry is realised in 4-dimensions and further, we successfully reproduce the gauge symmetry results. Using the SO(6) ⊗ SO(5) group, all the known aspects of the string theory are obtained. The model reduces to the Standard Model which has the capability of containing the ingredients of a successful theory of the present day physics. However, there are no Higgs in the model.

34 ref

010095   Chavan S D;Watode B D;Hudge P G;Suryawanshi D B;Akode C G;Kumbharkhane A C;Mehrotra S C (School of Physical Sciences, Swami Ramanand Teerth Marathwada Univ, Nanded-431 606) : Dielectric relaxation and hydrogen bond interaction study of diol-water mixtures. Indian J Phys 2010, 84(4), 419-29.

Complex dielectric permittivity measurements in the frequency range 10MHz-20GHz have been carried out in diol-water mixtures over the entire concentration range using a time domain reflectometry (TDK) method at 25°C. A hydrogen bonded theory is applied to compute the dielectric constant for the mixtures. It adequately reproduces the experimental values of static dielectric constants for the diol-water mixtures. The dielectric parameters confirm that the intermolecular homogeneous and heterogeneous hydrogen bonding vary significantly with the increase in concentration of the constituents of the diol-water mixtures.

12 illus, 2 tables, 21 ref

010094   Chauha D P S;Tiwari D P;Tripathi A K;Pandey S K;Dubey S C (Physics Dep, Awadesh Paratap Singh Univ, Rewa-486 003, Email: subhas1236@rediffmail.com) : Association of large geomagnetic storms with halo CMEs and CIRs observed during 1997-2007. Indian J Phys 2010, 84(7), 881-6.

In the study, authors have analysed large geomagnetic storms associated with storm time index (D_st) decrease of more than 100 nT observed during 1997-2007 and found 90 geomagnetic storms falling in our selection criteria. We have analyzed the association of the above selected 90 large geomagnetic storms with three types of solar drivers: single front-side halo CME (S-type), multiple front-side halo CMEs (M-type) and corotating interaction region, CIR (C-type). It is found that 58% storms were caused by single front-side halo CME (S-type), whereas 30% storms were caused by multiple front-side halo CMEs (M-type). Rest 12% storms were caused by corotating interaction region (CIR). We find that there is an east-west asymmetry and north-south asymmetry as well. We have also shown the association of the selected 90 large geomagnetic storms with three types of surface source region : active region, quiet region and coronal holes. We find that 62% storms were caused by active region whereas 10% storms were caused by quiet region. 12% storms were caused by coronal holes. Surface source region of rest 16% storms are unknown due to data gap.

3 illus, 23 ref

010093   Chandra Shekar N V;Kathirvel V;Sahu P C (Condensed Matter Physics Div, Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam-603 102) : Structural stability, phase transformations and band-tuning of actinide and rare earth based intermetallics under high pressure: a perspective. Indian J Phys 2010, 84(5), 485-99.

When a solid is subjectedto external pressure, it can undergo either structural transformation or remain stable in its parent structure. The sequence of structural transformations, when mapped for similar materials, viz., isostructural, isoelectronic and so on, can be used to create a map showing the evolution of structures under pressure for such materials. Such maps are useful in predicting high pressure phases. The structural transitions and the stability of materials as a function of pressure are intricately connected to their electronic structure. Many a times it is advantageous to know the stability of the material under pressure just by calculating its electronic structure. This can be accomplished only if several homologues materials are studied and the stability criteria arrived at by correlating their electronic structure with their structural stability under pressure. Further, as a function of pressure, the electronic structure changes can lead to enhancement in certain desired electronic, physical or mechanical properties. Several examples are known, wherein, pressure tuning of the band structure leads to improved properties. In this paper, we have discussed the above mentioned areas and presented a perspective of the above using the results of our own studies on f-electron based intermetallics (f-IMCs).

^iia7 illus, 1 table, 57 ref

010092   Brundabana Pradhan (Physics Dep, Government Science College, Malkangiri-764 048, Email: brunda@iopb.res.in) : Coexistence of Jahan-Teller effect and superconductivity in high-Tc superconductors. Indian J Phys 2010, 84(3), 279-89.

Using a simple model, the coexistence of superconductivity (SC) and the Jahn-Teller (JT) effect are studied for high-T_c cuprate systems. The interplay of SC and JT gaps is studied and found that in the coexistence phase the SC gap as well as the JT gap are suppressed. For calculations, the single particle Green's function technique of Zubarev is used. The density of states (DOS) and dispersion curves are also studied in the coexistence phase.

7 illus, 34 ref

010091   Borhade A V;Wakchaure S G;Dholi A G (Chemistry Dep, HPT Arts and RYK Science College, Research Centre, Nasik-422 005) : One pot synthesis and crystal structure of aluminosilicate mixed chloro-iodo sodalite. Indian J Phys 2010, 84(2), 133-41.

The crystal structure of different compositions of aluminosilicate mixed chloride and iodide sodalites was studied. The sodalites have been characterized by X-ray powder diffraction using Reitveld refinement in the space group P 4 3n. FT-IR spectroscopy shows the successful enclathration of chloride and iodide anions in the -cages of sodalite. Different sodalites are prepared under low temperature hydrothermal conditions in which zeolite A is used as starting material with variation of concentration of sodium chloride and iodide. The products obtained were washed with deionized water and dried overnight at 100°C. The increase in concentration of iodide shows that the Al-O-Si angle and distances in Na₈[AISiO₄]CI_2-xl_x sodalite (0<60> x ≤ 2) are modified considerably. X-ray diffraction study clearly shows variation in unit cell from 8.9241 to 8.991 OA with increase in concentration of sodium iodide. IR study also shows pronounced shift in frequency with concentration of iodide. Amount of chloride and bromide was determined by potentiometry. SEM study shows cubic crystal morphology.

5 illus, 2 tables, 25 ref

010090   Bhattacharya A B;Sarkar S;Bhattachrya R (Physics Dep, Kalyani Univ, Kalyani-741 235, Email: asit1951@yaoo.com) : Alternative search strategy for interstellar commuication. Indian J Phys 2010, 84(5), 511-15.

Are there any better wavelengths (or frequencies) for gathering information of extraterrestrial intelligence? In recent years scientists have realised that intelligent life may well be found throughout the universe and we are, perhaps, not the only civilization in our galaxy. The paper suggests an alternative search strategy of extraterrestrial life through sky noise windows emphasizing both the 'water-holes' and the associated wavelengths. It also suggests that instead of pointing the antenna at known stars, an all sky search would be more appropriate for interstellar communication.

2 illus, 9 ref

010089   Asghar J;Liakat Ali Khan F;Subramani K (Physics Dep, Islamiah College, Vamiyambadi-635 752, Email: j.asghar69@gmail.com) : Thermodynamic studies of molecular interactions in ternary liquid mixtures at various temperatures. Rasayan J Chem 2010, 3(4), 697-704.

Ultrasonic Velocity (U), density (p), and viscosity (μ) were measured for mixtures of 1-alkanols namely 1-pentanol, 1-hexanol and 1-octanol with Methyl Methacrylate (MMA) in Cyclohexane at 303K, 313K, and 323K. The experimental data was used to calculate various acoustical parameters like adiabatic compressibility (β), Free length (L_f), Free volume (V_f), Internal pressure (p), Acoustical impedance(Z) and Viscous relaxation time (τ).

3 tables, 18 ref

010088   Agarwal A;Singh M K;Vishnoi A N (Physics Dep, M. N. National Institute of Technology, Allahabad-211 004, Email: arvind@mnnit.ac.in) : XANES of the AuL_III edge in gold metal and in two compounds AuCN and AuCI₃. Indian J Phys 2010, 84(2), 199-204.

The X-ray Absorption Near Edge Structure (XANES) of the AuL_iii edge in gold metal and in its two compounds AuCN and AuCI₃ have been recorded. The observed chemical shifts of the edge and the fine structure peaks in the compounds are discussed. It is observed that the energy shifts Δ E of the AuL_III due to chemical effects in aurous cyanide (AuCN) and auric chloride (AuCl₃) with respect to the pure Au edge is 2.9 eV in AuCN and 0.7eV in AuCl₃. The edge widths in AuCN and AuCl₃ are found to be almost the same for both the compounds, presumably because electronegativities of CN and Cl are not very different. The observed fine structure peaks of the discontinuities of AuCN and AuCl₃ are displaced progressively away from the main edge.

1 illus, 2 tables, 29 ref

008906   Vishwakarma R K;Tiwari S (School of Studies in Electronics, Pt Ravishankar Shukla Univ, Raipur-492 010, Email: rkv_786@yahoo.com) : Dual-band stacked rectangular microstrip antenna. Indian J Radio Space Phys 2010, 39(3), 163-9.

A dual-band characteristic of stacked rectangular microstrip antenna is experimentally studied. It is a probe fed antenna for impedance matching with 50<78> coaxial cable. This antenna works well in the frequency range 2.86-4.63 GHz. It is basically a low cost, light weight medium gain antenna which is used for mobile communication. The variations of the length and width (1 mm) of the stacked rectangular patch antenna have been done. It is found to have dual resonance with increasing lower resonance frequency and almost constant upper resonance frequency with increases of the length and width of rectangular microstrip antenna. The input impedance and voltage standing wave ratio (VSWR) return loss have been measured with the help of network analyzer.

6 illus, 2 tables, 15 ref

008905   Toda Y R;Tayade D A;Chaudhari K S;Gujarathi D N (Physics Dep, Thin Film Laboratory, Pratap College, Amalner-425 401, Email: yogeshtoda@gmail.com) : Transport properties of bismuth thin films. Asian J chem envir Res 2010, 3(4), 16-8.

Bismuth is an important group V semi-metal. Its semi-metallic behavior arises due to overlapping of conduction band and valence band. It seems a promising material due to its small electron effective mass, anomalously high values of electron mean free path, mobility and highly anisotropic Fermi surface. Polycrystalline thin films having different thickness of bismuth were deposited by physical evaporation techniques, onto precleaned amorphous glass substrate. The electrical transport properties of annealed thin films have been evaluated. Bulk resistivity (4.2 X 10⁴ Ω-cm), activation energy (29 - 49 meV), mean free path (6201° Angstrum), carrier concentration (3.42 X 10¹⁷/cm³), Hall coefficient 49 - 59 X 10¹¹volt-cm/amp-Gauss), Hall mobility (125) has been estimated. The Seebeck coefficient indicates that all the films are p-type in nature and majority charge carriers in them are holes.

1 illus, 2 tables, 8 ref

008904   Suresh Chandra;Kumthekar B K;Dak G M (Physics Dep, Lovely Professional Univ, Pagawara-144 402, Email: suresh492000@yahoo.co.in) : Backward propagation of waves in solar plasma. Indian J Radio Space Phys 2010, 39(4), 184-6.

In order to have negative value of phase velocity, a wave moving in the backward direction should not be expressed as exp [i(k.r + ωt)], but as Exp [-i(k.r + <119>t)]. As the time is always increasing, this point has been argued in the present paper and has been justified with the help of some dispersion relations derived in the literature for propagation of waves in the solar plasma. It has been shown that the expression exp [i(k.f + ωt)] does not give physically meaningful results.

1 illus, 9 ref

008903   Singh G;Bhattacharjee T P;Mundra R;Yadav R P; Janyani V (Electronics & Communication Engineering Dep, Malaviya National Institute of Technology, Jaipur, Email: gschoudhary75@gmail.com) : Design and anaysis of the performance of a MZI-based all-optical switch exploiting the band gap shifting character of SOA's. J Optics 2009, 38(1), 29-37.

In this paper, an all-optical Mach-Zehnder interferometer (MZI) switch based on semiconductor optical amplifiers (SOA's) is taken into evaluation. The switch is designed while considering the optimum size of its various parts. The Gain shifted (or band gap shifted) (GS) switching scheme [1], is used to check its performance, which also lead to higher contrast ratio. The performance analysis of the switch is done by measuring the variations of output power with respect to changes in control signal wavelength, data signal power and control signal power, and graphically plotted. The optical spectrum and time domain analysis has been performed. The simulation results also brings forth facts, which establish the appropriate functioning of the switch architecture according to the principle of parallelism.

7 illus, 3 table, 11 ref

008902   Sawant D K;Patil H M;Bhavsar D S;Saraf K B (Physics Dep, Jijamata College, Nandurbar-425 412) : Thermal behaviour of gel grown mixed crystals of CA-SR tartrate. Asian J chem envir Res 2010, 3(4), 62-6.

Mixed crystals of Calcium-Strontium Tartrate were grown by a gel technique using Single diffusion method. The effect of various parameters like pH of gel, gel density, gel aging, and concentrations of reactants etc. on the growth of these crystals were studied. The crystals grown were characterized by Thermogravimetry (TGA) and Differential thermal analysis (DTA). The results of these observations are described and discussed.

2 tables, 27 ref

008901   Patil T K;Saraf K B (Smt G.G. Khadse Science, Arts and Comerce College, Muktainagar-425 306) : Growth and study of gel grown crystals of bismuth iodate Bi(Io₃)₃. Asian J chem envir Res 2010, 3(4), 78-83.

Crystals of Bismuth lodate were grown by a simple gel technique using single diffusion method. The optimum growth condition were established by varying various parameters such as PH of gel solution gel concentration and gel setting time, concentration of reactants etc. crystals having different morphologies and habits, the crystal structure of Bi(IO₃)₃ is monoclinic These crystals are transparent some were opaque and some translucent. The crystals were characterized using XRD, FTIR and chemical analysis.

4 illus, 8 tables, 15 ref

008900   Nishchal N K (Physics Dep, Indian Institute of Technology, Patna, Email: nkn@iitp.ac.in) : Optical image watermarking using fractional Fourier transform. J Optics 2009, 38(1), 22-8.

An optical image watermarking scheme using fractional Fourier transform is proposed. The watermark is encrypted using double random fractional order Fourier domain encoding scheme. Encrypted image is water marked into a host image. Embedding watermark sequences into fractional Fourier domain has an important advantage over embedding in spatial domain or in frequency domain. The watermark is recovered by applying corresponding correct fractional orders and random phase masks. The use of fractional Fourier transform offers additional degrees of freedom to enlarge the key size, thus enhancing the level of security. The effect of occlusion of watermarked image on the recovered watermark is also studied. The proposed idea is supported with simulation results.

2 illus, 20 ref

008899   Mishra G;Yadav R R;Kor S K (Physics Dep, Allahabad Univ, Allahabad-211 002, Email: giridharmishra@rediffmail.com) : Nondestructive characterization of a lyotropic liquid crystalline system. J pure appl Ultrasonics 2009, 31(1), 31-5.

In the present work, the characterization of a calamitic liquid crystal mixture-sodium lauryl sulphate (SLS)/decanol/water-has been reported using ultrasonic velocity and absorption measurements as a function of temperature and concentration. The experimental tools used were, ultrasonic interferometry for the velocity and pulse-echo technique for the absorption measurements. The results are discussed in terms of the temperature and concentration dependent lyotropic liquid crystal formed in the material system.

4 illus, 1 table, 22 ref

008898   Kaatze U (Drittes Physikalisches Institue, Georg-August-Universitat, Friedrich-Hund-Platz 1, 37077 Gottingen, Germany, Email: uka@physik3.gwdg.de) : Ultrasound techniques for characterizing liquids. II. survey of single frequency methods. J pure appl Ultrasonics 2009, 31(1), 13-23.

This paper focuses on acoustical methods for liquid measurements at a fixed frequency or in a small frequency band. Emphasis is particularly given to high-precision sound velocity measurements. Methods employing continuous waves and sharp pulses are discussed in detail. Related methods are also described briefly. The merits and limitations of the different methods of measurement are shown. Some examples of measurement applications are presented in order to indicate the favourable sensitivity of single methods and to reveal their extended usability in basic research and in manufacturing process.

7 illus, 77 ref