01967nas a2200241 4500008004100000022001400041245008300055210006900138260010600207300001200313490000700325520108500332653001801417653000801435653001301443653003401456653003601490653002001526100002001546700002401566700002201590856011301612 2006 eng d a0301-932200aEulerian-lagrangian simulations of unsteady gas-liquid flows in bubble columns0 aEulerianlagrangian simulations of unsteady gasliquid flows in bu aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJUL a864-8850 v323 a

We studied the dynamics of gas-liquid flows in a rectangular bubble column using Eulerian-Lagrangian simulations. Three-dimensional, unsteady simulations were performed to simulate the dynamic characteristics of the oscillating bubble plume. The effect of superficial gas velocity and aerated liquid height-to-column width (HI K) ratio on the dynamic and time-averaged flow properties was studied and the simulated results were validated using wall pressure and voidage fluctuation measurements. The effect of lift force and numerical diffusion on the dynamic and time-averaged properties is discussed in detail. Further, the results obtained using the Eulerian-Lagrangian simulations were compared with the Eulerian-Eulerian simulations. The bubble scale information, which is otherwise lost in the Eulerian-Eulerian simulations, was validated using the voidage fluctuation measurements. Such experimentally validated Eulerian-Lagrangian models will be useful for the simulation of mass transfer and reactions in bubble columns. (c) 2006 Elsevier Ltd. All rights reserved.

10aBubble column10aCFD10aDynamics10aEulerian-Eulerian simulations10aEulerian-Lagrangian simulations10agas-liquid flow1 aBuwa, Vivek, V.1 aDeo, Dhanannjay, S.1 aRanade, Vivek, V. uhttp://library.ncl.res.in/content/eulerian-lagrangian-simulations-unsteady-gas-liquid-flows-bubble-columns-000877nas a2200229 4500008004100000022001400041245008600055210006900141260010600210300000900316490000700325653001300332653002100345653002400366653002800390100002100418700002000439700001800459700002600477700002800503856011600531 2011 eng d a0079-656500aStructure determination and dynamics of protein-RNA complexes by NMR spectroscopy0 aStructure determination and dynamics of proteinRNA complexes by  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcFEB a1-610 v5810aDynamics10aNMR spectroscopy10aProtein-RNA complex10aStructure determination1 aDominguez, Cyril1 aSchubert, Mario1 aDuss, Olivier1 aRavindranathan, Sapna1 aAllain, Frederic, H. T. uhttp://library.ncl.res.in/content/structure-determination-and-dynamics-protein-rna-complexes-nmr-spectroscopy-002766nas a2200265 4500008004100000022001400041245005700055210005700112260000800169490000700177520201300184653001302197653002002210653002202230653001902252653001302271653000902284653002002293653001702313653000902330100002802339700001802367700002702385856008802412 2017 eng d a1744-683X00aCapillary uptake in macroporous compressible sponges0 aCapillary uptake in macroporous compressible sponges cSEP0 v133 a

The capillarity-driven uptake of liquid in swellable, highly porous sponges is of significant industrial importance. Sponges prepared using polymers and their composites with carbon nanotubes and graphene have been reported, with extraordinary solvent uptake capacities and with the ability to separate oil from water. However, the effect of systematic variation of sponge characteristics on solvent uptake has not been investigated. Here, we report experiments that study capillary uptake in a variety of flexible, centimetre-sized macroporous cylindrical sponges. We used ice-templating to prepare a series of model macroporous sponges in which the porosity, modulus and composition were systematically varied. We investigated two kinds of sponge: (a) those composed purely of cross-linked polymers and (b) those prepared as composites of inorganic particles and polymers. Both kinds of sponge are flexible and exhibit elastic recovery after large compressive deformation. All sponges were characterized thoroughly with respect to their pore microstructure and elastic modulus. When one end of a sponge is plunged into a large reservoir, water rises through capillary action against gravity. We observed a transition from an inertial capillary regime, where the liquid column height rose linearly with time, t, to a viscous capillary regime, where the liquid height rose with time t(0.5). We showed that these results can be rationalized using analyses developed for rigid sponges. We combined differential momentum balance equations for uptake in rigid capillaries with the phenomenological Ergun-Forchheimer relations to account for the effect of the sponge microstructure. This approach works remarkably well in the viscous capillary regime and shows that capillary uptake is governed primarily by the total porosity and pore dimensions of soft sponges.

10aaerogels10aBuilding blocks10aCatalyst Supports10aContact-angels10aDynamics10aflow10aOrganic Liquids10aPorous-Media10aRise1 aChatterjee, Soumyajyoti1 aDoshi, Pankaj1 aKumaraswamy, Guruswamy uhttp://library.ncl.res.in/content/capillary-uptake-macroporous-compressible-sponges02539nas a2200253 4500008004100000022001400041245013000055210006900185260000800254490000800262520161400270653001101884653001301895653001601908653001101924653001101935653001101946653002301957653010301980653003002083100002102113700002502134856012602159 2017 eng d a0021-979700aStudies on the role of unsaturation in the fatty acid surfactant molecule on the thermal conductivity of magnetite nanofluids0 aStudies on the role of unsaturation in the fatty acid surfactant cNOV0 v5063 a

To study the role of unsaturation in the surfactant molecule on the thermal conductivity of magnetite nanofluids, four different fatty acid (stearic, oleic, linoleic, and linolenic acids with different degree of unsaturation) coated magnetite nanoparticles of comparable size are prepared and dispersed in toluene. It is found that the nanofluid with the saturated fatty acid coated nanoparticles show larger viscosity than the fluid with the unsaturated fatty acid coated particles at all concentrations. Thermal conductivity studies show enhancement only above a critical concentration for all fluids. The critical concentration for thermal conductivity enhancement varies with the surfactant, possibly due to the difference in the degree of aggregation of the nanoparticles in the fluid, because of the difference in the conformation of the surfactant molecules on the nanoparticle's surface. The experimental thermal conductivity follows the Maxwell model at higher concentrations. From the overall studies, it is observed that the thermal conductivity of the fluids with aggregated or assembled nanoparticles shows slightly larger enhancement than that of the fluids with isolated particles. However, in the presence of a magnetic field, the fluids with isolated nanoparticles showed relatively larger enhancement, possibly due to the easy response of the isolated magnetite nanoparticles to the applied field. (C) 2017 Elsevier Inc. All rights reserved.

10aChains10aDynamics10aEnhancement10aFields10aFluids10aForces10agold nanoparticles10aMagnetic fluid; Nanofluid; Surfactant; Unsaturation; Conformation; Thermal conductivity; Viscosity10aSelf-assembled Monolayers1 aLenin, Ramanujam1 aJoy, Pattayil, Alias uhttp://library.ncl.res.in/content/studies-role-unsaturation-fatty-acid-surfactant-molecule-thermal-conductivity-magnetite