http://nopr.niscair.res.in/handle/123456789/8606 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/8721 Title: Current-mode universal biquadratic filter with single input and four outputs using FTFNs <br/> <br/>Authors: Shah, N A; Malik, M A <br/> <br/>Abstract: A novel four terminal floating nullor (FTFN) based universal current-mode (CM) biquadratic filter configuration with single input and four outputs (SIFO) is presented<b style="">. </b>The circuit is based on and employs six FTFNs of the same polarity and as many passive components and realizes simultaneously lowpass (LP), highpass (HP), inverted bandpass (BP) and Notch filtering functions without any imposition of component matching conditions or cancellation constraints. The circuit can also be made to realize allpass (AP) response by tying together appropriate output filtering signals. The topology has the distinct feature of low input and high output impedances which permits easy cascading for the construction of higher order filters. The circuit enjoys low passive sensitivity figures. The resonance frequency ω_oand bandwidth ω_o/Q can be independently tuned while as resonance frequency ω_oandquality factor Q can be orthogonally adjusted. Experimental and PSPICE simulation results are given to confirm the theoretical results.<b style=""> </b> <br/> <br/>Page(s): 142-144 http://nopr.niscair.res.in/handle/123456789/8720 Title: Thermal conductivity, diffusivity and heat capacity of plasticized polyvinyl chloride <br/> <br/>Authors: Dashora, P; Gupta, G; Dashora, J <br/> <br/>Abstract: Simple formalisms for thermal conductivity <i style=""><img src='/image/spc_char/lamda.gif' border=0> </i>, thermal diffusivity <i style="">D</i> and specific heat <i style="">C_p</i> of both linear and cross-linked amorphous polymers has been presented. These relations explain successfully the dependence of these properties on temperature and amount of plasticizer. Present study reveals that the santicizer-160 forms cross-linkage among the linear chains of polyvinyl chloride (PVC). The structural transition at <i style="">T_g</i>, the anti-plasticization effect below <i style="">T_g</i> and plasticization effect above <i style="">T_g</i>, are clearly reflected in the trends of these properties. The calculated values of all the three properties for PVC plasticized with different amount of plasticizer (Santicizer-160: 10 phr, 20 phr and 30 phr) are in excellent agreement with the experimental values over a wide range of temperature, which includes glassy, leathery and rubbery regions. The maximum deviation in experimental and calculated values is less than 5% for all these properties. <br/> <br/>Page(s): 132-136 http://nopr.niscair.res.in/handle/123456789/8719 Title: Variation of optical band gap in obliquely deposited selenium thin films <br/> <br/>Authors: Singh, M; Bhahada, K C; Vijay, Y K <br/> <br/>Abstract: The selenium thin films of obliquely and normal deposited for different thickness were prepared using thermal evaporation method at pressure of 10^{- 5}torr on to the glass substrate at room temperature. The band gap of thin films with respect to normal to vapour beam direction decreases with angle of deposition, which may be due to small increase in the thickness of the thin films with angle of deposition. The optical band gap has also been observed for different thin films having large variation in thickness.The optical energy band gap of these films decreases with thickness due to quantum size effect. <br/> <br/>Page(s): 129-131 http://nopr.niscair.res.in/handle/123456789/8718 Title: Electrical conductivity and dielectric measurements in Au⁺doped/undoped KDP crystals with KCl and NaCl as additives <br/> <br/>Authors: Kumari, R Ananda; Chandramani, R <br/> <br/>Abstract: Pure potassium dihydrogen orthophosphate (KDP) containing KCl or NaCl with and without gold doping were grown by slow evaporation technique. All the grown crystals were <img src='/image/spc_char/gamma.gif' border=0>-irradiated using ⁶⁰Co source. Electrical conductivity measurements were carried out perpendicular to the unique direction before and after g-irradiation. The conductivity of KDP crystals increases with the addition of KCl and NaCl and with gold doping as well as temperature. Computed values of activation energies from the conductivity measurements are given. The dielectric constant and dielectric loss have been measured as a function of frequency. The study confirms the contribution of space charge polarization. <br/> <br/>Page(s): 123-128