http://nopr.niscair.res.in/handle/123456789/6243 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/6256 Title: Critical assessment of Flory’s approach for estimating miscibility gap in binary monotectic systems <br/> <br/>Authors: Chaubey, Sanjay <br/> <br/>Abstract: Flory’s  solution approach, which gives expression for the free energy of mixing of binary alloys whose constituent atoms differ largely in size, has been used to find the required model parameters in terms of which expressions for critical temperature (<i>T_c</i>) and critical composition  (<i>X_c</i>) have been derived. Model parameters are capable of describing the thermodynamic behavior of the liquid phase and are useful in constructing the miscibility gap in binary monotectics. Within the limits fairly good agreement has been observed between theoretically calculated and experimentally observed values of <i>X_c</i>  and <i>T_c</i>  along with the reasonable data for the various thermodynamic functions at the desired temperature in four binary monotectic systems chosen for the present study. <br/> <br/>Page(s): 364-366 Mon, 28 Sep 2009 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/6255 Title: Charge transport and ammonia sensing response in poly (aniline-co-1-amino- 2-naphthol-4-sulphonic acid) <br/> <br/>Authors: Bansal, Vineet; Bansal, M C; Dhawan, S K <br/> <br/>Abstract: The paper reports the synthesis of tubes of poly (aniline-co-1-amino-2-naphthol-4-sulphonic acid) using para toluene sulphonic acid as a dopant. The copolymers have the conductivity of the order of 0.348 S/cm to 0.198 S/cm depending on the ratio of the co-monomers present in the feed ratio. The morphology of the copolymers was studied by scanning electron microscope. Electrical conduction have been studied in the temperature range from 300 K to 30 K. Charge transport has been attributed as tunnelling in the range 30 K to 70 K. Above 70 K, charge transport is represented by Mott’s three-dimensional variable hopping. The copolymer has been found to be a better ammonia vapour sensing material and can be used for detection for varying concentration. <br/> <br/>Page(s): 355-363 Mon, 28 Sep 2009 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/6254 Title: Innovative low pressure borophosphosilicate glass processes for nano devices <br/> <br/>Authors: Jagadeesha, T; Kim, Louis; Gonsalvis, Joseph; Gowda, Thammaiah <br/> <br/>Abstract: Doping of oxide with phosphorous can trap mobile ions and reduce the re-flow temperature. By adding boron the reflow temperature can be reduced further without excessive phosphorous, which may cause metal corrosion. Borophosphosilicate glass (BPSG) and phosphosilicate glass (PSG) processes are mainly used for premetal dielectric (PMD) applications. In the present study, a new low pressure BPSG process has been developed which can be used for Flash memory and Logic devices. It is shown that films with phosphorus and boron concentrations in the range of 1.85-9.15 elemental wt% are deposited with film thickness 6000 Å BPSG and 100 Torr process has been found to achieve more stable film thickness. Decreasing the deposition pressure from 200 to 100 Torr results in a 50% increase in the deposition rate of twin-wafer SACVD BPSG and has zero effect on film properties. Throughput has been improvement by 20% on SACVD PMD BPSG application. <br/> <br/>Page(s): 341-346 Mon, 28 Sep 2009 22:58:59 GMT http://nopr.niscair.res.in/handle/123456789/6253 Title: Growth and characterization of tetravalent doped LiCoO₂thin film cathodes <br/> <br/>Authors: Rao, M C; Hussain, O M <br/> <br/>Abstract: Titanium-doped LiCoO₂thin films are grown by pulsed laser deposition technique on silicon substrates. Structure, AFM, FTIR and Raman are studied with respect to their deposition parameters, i.e., substrate temperature (<i style="">T</i>_s) and oxygen partial pressure (pO₂) in the deposition chamber. The films deposited in pO₂ = 100 mTorr showed good crystallinity on silicon substrates maintained at <i style="">T</i>_s = 700°C. It is found that such a film crystallizes in the layered <img src='/image/spc_char/alpha.gif'>-NaFeO₂ structure. The influence of titaniumdoping on particle size and morphologies has been clearly studied. FTIR spectra displayed the characteristic IR dominant bands at 246 and 550 cm^–1for titanium doped LiCoO₂thin films. The Raman peaks observed for the films at 594 cm^-1 and 485 cm^-1 are ascribed to Raman active modes A_1g and E_g respectively. The electrochemical measurements were carried out on Li//LiTi_yCo_1-yO₂ cells. The Li//LiTi_yCo_1-yO₂ cell delivered a specific capacity of 225 mC/<img src='/image/spc_char/micro.gif'>m cm². The influence of titaniumdoping on the structural and electrochemical properties has been systematically studied. <br/> <br/>Page(s): 335-340 Mon, 28 Sep 2009 22:58:59 GMT