01822nas a2200193 4500008004100000022001400041245011000055210006900165260007100234300001600305490000800321520104600329100002501375700002301400700001701423700003001440700002701470856013101497 2013 eng d a1520-610600aExclusion from hexagonal mesophase surfactant domains drives end-to-end enchainment of rod-like particles0 aExclusion from hexagonal mesophase surfactant domains drives end a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcOCT a12661-126680 v1173 a

Anisotropic rod-like particles assemble end-to-end when the surfactant/water matrix in which they are dispersed is cooled from the isotropic to the lyotropic hexagonal phase. We demonstrate the formation of such end-to-end assemblies for gold nanorods, which are tens of nanometers in size, as well as for micrometer-sized ellipsoidal polystyrene particles. In both cases, the particles are well-dispersed in the low-viscosity surfactant/water phase above the isotropic-H-1 transition temperature. On cooling into the H-1 phase, mesophase domains form and the particles are expelled to the isotropic phase. As the H-1 domains grow and finally impinge, the particles are localized at the domain boundaries where they reorient and assemble end-to-end. Remarkably, we observe the formation of end-to-end assemblies of gold nanorods even for volume fractions as low as 2 x 10(-6) in the initially dispersed state. The extent of particle ``enchainment'' increases with the particle concentration and with the aspect ratio of the particles.

1 aSharma, Kamendra, P.1 aGanai, Anal, Kumar1 aSen, Debasis1 aPrasad, Bhagavatula L. V.1 aKumaraswamy, Guruswamy uhttps://library.ncl.res.in/content/exclusion-hexagonal-mesophase-surfactant-domains-drives-end-end-enchainment-rod-particles-001934nas a2200277 4500008004100000022001400041245010500055210006900160260011000229300001600339490000600355520091900361100001901280700002501299700001601324700001801340700002201358700002701380700002301407700001701430700001701447700001701464700002001481700002401501856013101525 2015 eng d a2046-206900aMesoporous TUD-1 supported indium oxide nanoparticles for epoxidation of styrene using molecular O-20 aMesoporous TUD1 supported indium oxide nanoparticles for epoxida aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY a46850-468600 v53 a

Activation of molecular O-2 by metal or metal oxide nanoparticles is an area of recent research interest. In this work, for the first time, we report that indium oxide nanoparticles of <3 nm size dispersed on mesoporous silica (TUD-1) can activate molecular O-2 and produce styrene epoxide with a selectivity of 60% and styrene conversion around 25% under mild conditions. It is found that neither indium oxide nor TUD-1 themselves respond to the styrene epoxidation reaction. The computational studies provide evidence that an oxygen molecule is highly polarized when it is located near the interface of both surfaces. The kinetic study shows that the reaction is of pseudo-first order and that the activation energy for styrene conversion is 12.138 kJ mol(-1). The catalysts are recyclable for up to four regeneration steps, with the styrene conversion and styrene epoxide selectivity almost unchanged.

1 aRahman, Sumbul1 aFarooqui, Saleem, A.1 aRai, Aditya1 aKumar, Rawesh1 aSantra, Chiranjit1 aPrabhakaran, Vinod, C.1 aBhadu, Gopala, Ram1 aSen, Debasis1 aMazumder, S.1 aMaity, Sudip1 aSinha, Anil, K.1 aChowdhury, Biswajit uhttps://library.ncl.res.in/content/mesoporous-tud-1-supported-indium-oxide-nanoparticles-epoxidation-styrene-using-molecular-002076nas a2200289 4500008004100000022001400041245008500055210006900140260000900209300001200218490000800230520120100238653001801439653001701457653001101474653000901485653001101494100001801505700001601523700002201539700002601561700001701587700001701604700002801621700002401649856011301673 2016 eng d a1387-181100aHighly stable In-SBA-15 catalyst for vapor phase Beckmann rearrangement reaction0 aHighly stable InSBA15 catalyst for vapor phase Beckmann rearrang cNOV  a293-3020 v2343 a

The Indium doped SBA-15 material was prepared by sol-gel method and tested for vapor phase Beckman rearrangement reaction. Among three indium loading, In/Si ratio of 2/100 was found as an optimum composition in terms of caprolactam selectivity (100%) and cyclohexanone oxime conversion (100%). The catalysts were characterized by N-2 adsorption, small-angle X-rays/neutron scattering (SAXS/SANS), XRD, FESEM, HRTEM, EDX, UV, FTIR and NH3-TPD techniques. In-situ SANS experiment was performed on the adsorption of CO2 to detect the micropores in the mesopore wall. All catalysts samples have highly ordered hexagonal structure with well dispersed indium in the silica matrix. The fine tuning of weak and strong acid sites were found in indium doped SBA-15 (In/Si = 2/100) catalyst. The same catalyst showed optimum catalytic performance, high space time yield 114.4 mol/h/g(cat) and high stability till 6 h of reaction without deactivation. The micro-kinetic analysis showed that there were no external and internal diffusion limitations in the SBA-15 catalyst. The reaction mechanism of Beckmann rearrangement over In-SBA-15 has been elucidated. (C) 2016 Elsevier Inc. All rights reserved.

10ae-Caprolactam10aIn-situ SANS10aindium10aSAXS10aSBA-151 aKumar, Rawesh1 aShah, Sneha1 aBahadur, Jitendra1 aMelnichenko, Yuri, B.1 aSen, Debasis1 aMazumder, S.1 aVinod, Chathakudath, P.1 aChowdhury, Biswajit uhttps://library.ncl.res.in/content/highly-stable-sba-15-catalyst-vapor-phase-beckmann-rearrangement-reaction02634nas a2200229 4500008004100000022001400041245013300055210006900188260000800257300001200265490000800277520185100285100002402136700002302160700002102183700002102204700001702225700001702242700002202259700000502281856011802286 2018 eng d a0169-433200aControlled surface/interface structure and spin enabled superior properties and biocompatibility of cobalt ferrite nanoparticles0 aControlled surfaceinterface structure and spin enabled superior  cNOV a788-8010 v4593 aHigh quality, crystalline, well-dispersed, and stable magnetic oxide nanoparticles (NPs) of inverse spinel cobalt ferrite (CoFe2O4; CFO) were prepared by a facile, reproducible, and simple hydrothermal route. The transmission electron microscopy, small-angle scattering and X-ray diffraction analyses demonstrate the structural quality of CFO NPs with a controlled size of similar to 12 nm. Small-angle scattering experiments demonstrate that the pristine CFO NPs have the individual size similar to 8.5 nm and spherical shape. The Raman and infrared spectroscopic measurements further confirm their high chemical quality and cubic symmetry. CFO NPs exhibit a remarkable, maximum coercivity (H-c) value of 18.92 kOe, which is the highest value achieved to date. Surface spins and spins canting along with a weak dipolar interaction accounts for the giant H-c and large effective anisotropy (11.45 x 10(6) erg/cm(3)) of these CFO NPs. The magnetic grain size of NPs reveals that the canted surface spins exist around the magnetic particles. Reorientation of surface spins and interparticle interaction causes the jumping behaviour in M-H hysteresis loops at H = 0. The cell viability of CFO NPs against the cancer (cisplatin resistant ovarian cancer - A2780/CP70) was evaluated to determine their potential application in biomedicine and health science. The mild response of CFO NPs in terms of their anti-proliferative nature against cancer cells and negligible cytotoxicity suggests their human-safe-and-friendly nature which makes them suitable for biomedical/health-related applications. Assessment of toxicity toward human red blood cells (RBC) revealed that hemolysis is less than 5% compared to the positive control confirming the potential applications of CFO NPs targeting human cells and making relevant for adopting them in biomedicine.1 aAnsari, Sumayya, M.1 aSinha, Bhavesh, B.1 aPai, Kalpana, R.1 aBhat, Suresh, K.1 aMa, Yuan-Ron1 aSen, Debasis1 aKolekar, Yesh, D.1 a uhttps://library.ncl.res.in/content/controlled-surfaceinterface-structure-and-spin-enabled-superior-properties-and02461nas a2200181 4500008004100000022001400041245010600055210006900161260000800230300001400238490000700252520181400259100001902073700001702092700002002109700002702129856012302156 2019 eng d a0024-929700aCharacterizing microvoids in regenerated cellulose fibers obtained from viscose and lyocell processes0 aCharacterizing microvoids in regenerated cellulose fibers obtain cJUN a3987-39940 v523 a

Regenerated cellulose fibers are among the most widely used bio-derived materials. Currently, there is great interest in transitioning from the traditional viscose process to the more environmentally friendly lyocell process for fiber production. Differences between the characteristics of viscose and lyocell fibers can be attributed to microstructural differences that arise due to differences in the processing techniques. Here, we use small-angle scattering to characterize the microvoids in regenerated cellulose fibers that might govern the onset of mechanical failure in these. In regenerated cellulose fibers, scattering of X-rays or neutrons at small angles is largely dominated by scattering from microvoids. We demonstrate that small angle X-ray scattering (SAXS) over the q range that is typical for most commercial instruments arises from Porod scattering from the microvoid surfaces, viz., the scattered intensity scales as q(-4). Therefore, it is not possible to extrapolate this data to lower q to obtain microvoid dimensions and volume fraction. We combine SAXS with medium-resolution small-angle neutron scattering to characterize the microvoids in regenerated cellulose fibers. Specifically, we compare fibers produced using the viscose process with those from the lyocell process. For both viscose and lyocell fibers, microvoids have a high aspect ratio and are elongated in the fiber direction. Also, the volume fraction occupied by the microvoids is comparable for viscose and lyocell fibers (0.04-0.05%). However, there are differences in the microvoid size: Microvoids are more highly oriented in lyocell fibers and have a larger average length and diameter compared with viscose fibers. This result might have important implications for understanding failure of these fibers.

1 aSharma, Aakash1 aSen, Debasis1 aThakre, Shirish1 aKumaraswamy, Guruswamy uhttps://library.ncl.res.in/content/characterizing-microvoids-regenerated-cellulose-fibers-obtained-viscose-and-lyocell01654nas a2200253 4500008004100000022001400041245016200055210006900217260000900286300001400295490000600309520073200315653003201047653001401079653001801093653003401111653002001145100002701165700002701192700001701219700001701236700002401253856012301277 2019 eng d a2365-654900aPalladium impregnated amine Co-condensed hexagonal mesoporous silica: a novel catalyst in tailoring suzuki and heck coupling reactions in base free condition0 aPalladium impregnated amine Cocondensed hexagonal mesoporous sil cAPR  a3823-38320 v43 a

Palladium impregnated amine co-condensed hexagonal mesoporous silicas (HMS-X) were synthesized (sol-gel process) using different amines (Ethylene diamine and pyridine) of various concentrations (0.25 equiv. and 2 equiv.). The effect of amine concentration on the local structure of hexagonal mesoporous silica was studied. The catalyst shows excellent catalytic activity and high TOF towards both Suzuki and Heck coupling reactions without using any base in reaction medium with the solvent DMF:water in (1:1) ratio. The catalyst was reused and it was recyclable up to three cycle without any appreciable loss of activity and the kinetics of the reaction varying different parameters also have been studied thoroughly.

10aAmine functionalized silica10aBase free10aHeck reaction10aPalladium supported catalysts10aSuzuki reaction1 aDas, Prangya, Paramita1 aPrabhakaran, Vinod, C.1 aNanda, Samik1 aSen, Debasis1 aChowdhury, Biswajit uhttps://library.ncl.res.in/content/palladium-impregnated-amine-co-condensed-hexagonal-mesoporous-silica-novel-catalyst01929nas a2200337 4500008004100000022001400041245007900055210006900134260000800203300000700211490000700218520093900225653002801164653001201192653001601204653001301220653002001233100001901253700002301272700001901295700001701314700001801331700001701349700001601366700001701382700002101399700001901420700002301439700001601462856011301478 2026 eng d a0250-470700aFly-ash-based geopolymers: leachability and solid-state NMR investigations0 aFlyashbased geopolymers leachability and solidstate NMR investig cMAR a540 v493 a

This study aims to explore how leaching impacts the microstructure of a selected fly ash-derived geopolymer and evaluate its potential for near-surface disposal of radioactive waste. The uniqueness of this geopolymer formulation is its ability to form an aluminosilicate network that remains resistant to structural changes upon contact with water. The leach index of base elements such as Ca, Al, Na and Si was between 11 and 13, suggesting that the formulation is superior to Portland cement or conventional hydraulic cement. Solid-state NMR reveals that the water-interacted specimen has no contamination of the zeolite phase and all the Na is incorporated into the aluminosilicate geopolymer gel network, which also confirms that the glassy network of the geopolymer is responsible for imparting low leachability of base elements from its structure, and there is no labile sodium available for exchange as in zeolites.

10aaluminosilicate network10aFly ash10aGeopolymers10aleaching10aSolid-state NMR1 aNadol, Athulya1 aAjithkumar, T., G.1 aSingla, Rashmi1 aAlex, T., C.1 aKumar, Sanjay1 aBhatt, Himal1 aDeo, M., N.1 aSen, Debasis1 aAmbashta, R., D.1 aBajpai, R., K.1 aShivakumar, Y., C.1 aManohar, S. uhttps://library.ncl.res.in/content/fly-ash-based-geopolymers-leachability-and-solid-state-nmr-investigations