01283nas a2200241   4500008004100000022001400041245017100055210006900226260010600295300001400401490000700415520030600422653001700728653001200745653001400757653003300771653002000804100001900824700002300843700001900866700002600885856013000911       2010                        eng d  a0040-403900aSynthesis of optically pure 2,3,4-trisubstituted tetrahydrofurans via a two-step sequential Michael-Evans aldol cyclization strategy: total synthesis of (+)-magnolone0 aSynthesis of optically pure 234trisubstituted tetrahydrofurans v  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJUN  a2975-29780 v513 a<p>Synthesis of optically pure 2,3,4-trisubstituted tetrahydrofurans is described employing a two-step Michael-Evans aldol cyclization strategy. The approach is successfully applied for the total synthesis of furano lignan natural product (+)-magnolone. (C) 2010 Elsevier Ltd. All rights reserved.</p>10aHWE reaction10aLignans10aMagnolone10aMichael-Evans aldol reaction10aTetrahydrofuran1 aPandey, Ganesh1 aLuckorse, Srikanth1 aBudakoti, Asha1 aPuranik, Vedavati, G.  uhttps://library.ncl.res.in/content/synthesis-optically-pure-234-trisubstituted-tetrahydrofurans-two-step-sequential-michael-002922nas a2200265   4500008004100000022001400041245013800055210006900193260009900262300001200361490000800373520191900381653002102300653002402321653001902345653001502364653002002379653002202399100002902421700001802450700001902468700002602487700001902513856012402532       2016                        eng d  a0016-236100aEnhanced clathrate hydrate formation kinetics at near ambient temperatures and moderate pressures: Application to natural gas storage0 aEnhanced clathrate hydrate formation kinetics at near ambient te  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcOCT  a907-9190 v1823 a<p>SNG (solidified natural gas) technology via clathrate hydrates is a potential method for large scale stationary storage of natural gas. Clathrate hydrate formation kinetics in presence of methane and 5.6 mol% tetrahydrofuran (THF) was investigated in an unstirred reactor configuration at moderate pressure and temperature conditions. It is well known that the presence of THF generally improves the thermodynamic stability of the resulting hydrate. In order to study the scale-up potential of this approach, kinetics of hydrate growth at temperatures close to ambient conditions and moderate pressures is required. Hydrate formation experiments were performed at three different temperatures - 283.2 K, 288.2 K and 293.2 K and at experimental pressures of 7.2 MPa, 5.0 and 3.0 MPa. Further, we report a synergistic effect of kinetic promotion of mixed methane hydrate formation by coupling THF and sodium dodecyl sulfate (SDS) at 293.2 K. For the first time, we observe rapid mixed methane/THF hydrate formation kinetics at 293.2 K in presence of just 100 ppm sodium dodecyl sulfate surfactant with methane gas uptake of 3.45 (+/- 0.17) kmol/m(3) of water in 1 h. This is also the first study to demonstrate such rapid hydrate formation kinetics with significant methane storage capacity at temperature of 293.2 K (closer to the ambient temperature). Further, substantial methane gas uptake of 3.52 (+/- 0.13) kmol/m(3) of water is possible even at reduced experimental pressure of 3.0 MPa and 283.2 K in 2 h. Minimal energy requirement in an unstirred reactor for mixed methane/THF hydrate formation storage can propel the SNG technology for large scale commercial deployment. Further improvement in the process can be achieved by optimizing the cooling requirement through innovative reactor design and operating the process in a semi-batch or continuous mode. (C) 2016 Elsevier Ltd. All rights reserved.</p>10aMethane hydrates10aNatural gas storage10aRapid kinetics10asurfactant10aTetrahydrofuran10aUnstirred reactor1 aVeluswamy, Hari, Prakash1 aKumar, Sharad1 aKumar, Rajnish1 aRangsunvigit, Pramoch1 aLinga, Praveen  uhttps://library.ncl.res.in/content/enhanced-clathrate-hydrate-formation-kinetics-near-ambient-temperatures-and-moderate02289nas a2200289   4500008004100000022001400041245009800055210006900153260006900222300001200291490000800303520126100311653001901572653002201591653001701613653002401630653002001654653002701674100002901701700002601730700002301756700001901779700002601798700002601824700001901850856013001869       2016                        eng d  a1385-894700aRapid methane hydrate formation to develop a cost effective large scale energy storage system0 aRapid methane hydrate formation to develop a cost effective larg  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcAPR  a161-1730 v2903 a<p>Natural gas (NG) is the cleanest burning fossil fuel and its usage can significantly reduce CO2 emissions from power plants. With its widespread use, there is an ever increasing need to develop technologies to store NG on a large scale. NG storage via clathrate hydrates is the best option for a large scale storage system because of its non-explosive nature, mild storage conditions, high volumetric capacity and being an environmentally benign process. In this work, we demonstrate a new method to achieve rapid methane hydrate formation in an unstirred tank reactor configuration (UTR) at moderate temperature and pressure conditions employing tetrahydrofuran (THF) as a promoter. For the first time, THF is reported to act both as a thermodynamic and an excellent kinetic promoter for methane hydrate formation. We demonstrate a multi-scale experimental validation of our method to a volumetric sample scale-up factor of 120 and internal reactor diameter scale-up factor of 10. Further, new insights on the dissociation behavior of the hydrates are reported. There is a competitive edge for storing NG via clathrate hydrates compared to compressed natural gas storage both in terms of cost and safety. (C) 2016 Elsevier B.V. All rights reserved.</p>10aEnergy storage10aEnhanced kinetics10aGas hydrates10aNatural gas storage10aTetrahydrofuran10aUnstirred tank reactor1 aVeluswamy, Hari, Prakash1 aWong, Alison, Jia Hui1 aBabu, Ponnivalavan1 aKumar, Rajnish1 aKulprathipanja, Santi1 aRangsunvigit, Pramoch1 aLinga, Praveen  uhttps://library.ncl.res.in/content/rapid-methane-hydrate-formation-develop-cost-effective-large-scale-energy-storage-system-0