@article { ISI:000245534900008, title = {Selective mono-N-methylation of aniline substrates on Cu1-xZnxFe2O4}, journal = {Applied Catalysis A-General}, volume = {320}, year = {2007}, month = {MAR}, pages = {64-68}, publisher = {ELSEVIER SCIENCE BV}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Selective mono-N-methylation of substituted anilines (o-, m- and p-toluidines, 2,6-xylidine, p-anisidine and p-aminoacetophenone) was carried out with methanol as methylating agent under vapor phase reaction conditions on Cu1-xZnxFe2O4 systems. The catalytic reactions with each aniline substrate were carried out at optimum reaction conditions (MeOH:anilines:water = 3: 1: 1, space velocity = 3.58 h(-1)) between 543 and 603 K. The presence of a ring-directing group did not have any significant influence on the N-methylaniline(s) selectivity, which remains very high; the same initial conversion/yield was observed for at least 11 h. Electronic effects due to different groups in the above aniline substrates influence the reactivity of the substrates in terms of conversion and yield. Toluidine reactivity varies with respect to the position (ortho, meta and para) of the methyl group on the phenyl ring. Para-substituted anilines (p-toluidine and p-anisidine) exhibit comparable catalytic activity, while p-aminoacetophenone shows higher conversion. The perpendicular orientation of toluidine substrates on catalyst surfaces influences the conversion and N-methyltoluidine yield. Increased crowding at ortho-position and hence steric hindrance (aniline \> o-toluidine \> 2,6-xylidine) restrict the substrates interaction with the catalyst surface, and 2,6-xylidine shows no reactivity. The best catalytic activity observed with Cu0.5Zn0.5Fe2O4 was due to a heterogeneous distribution of metal ions on the surface with Zn serving as active spacer group as well as methyl species source. (c) 2007 Elsevier B.V. All rights reserved.

}, keywords = {mono-N-methylation, N-methylaniline, N-methylation, selective N-methvlation, spinel}, issn = {0926-860X}, doi = {10.1016/j.apcata.2006.12.016}, author = {Vijayaraj, Munusamy and Gopinath, Chinnakonda S.} } @article { ISI:000370057200011, title = {Enhanced electron field emission from NiCo2O4 nanosheet arrays}, journal = {Materials Research Express}, volume = {2}, number = {9}, year = {2015}, month = {SEP}, pages = {095011}, publisher = {IOP PUBLISHING LTD}, address = {TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND}, abstract = {

Electron emission properties of electrodeposited spinel NiCo2O4 nanosheet arrays grown on Ni foam have been studied. The work function of NiCo2O4 was calculated by density functional theory using the plane-wave basis set and used to estimate the field enhancement factor. The NiCo2O4 nanosheet arrays exhibited a low turn-on field of 1.86 V mu m(-1) at 1 mu A cm(-2) and current density of 686 mu A cm(-2) at 3.2 V mu m(-1), with field enhancement factor beta = 1460 and good field emission current stability. The field emission properties of the NiCo2O4 nanosheet arrays showed enhanced performance compared to chemically prepared NiCo2O4 nanosheets. Hence, the nanosheet arrays have great potential as robust high performance vertical structure electron emitters for future flat panel displays and vacuum electronic device applications.

}, keywords = {Density functional theory, field emission, nanosheets, NiCo2O4, spinel}, issn = {2053-1591}, doi = {10.1088/2053-1591/2/9/095011}, author = {Naik, Kusha Kumar and Khare, Ruchita T. and Gelamo, Rogerio V. and More, Mahendra A. and Thapa, Ranjit and Late, Dattatray J. and Rout, Chandra Sekhar} } @article {47895, title = {Catalytic activity of CuFe2O4 spinel oxide for liquid-phase oxidation of cinnamyl alcohol}, journal = {ChemistrySelect}, volume = {7}, year = {2022}, month = {FEB}, pages = {e202104441}, type = {Article}, abstract = {

CuFe2O4 spinel oxide catalyst was synthesized by sol-gel and co-precipitation methods for liquid phase oxidation of Cinnamyl alcohol (CnOH) to Cinnamaldehydes (CnHO) using tert-Butyl hydroperoxide (TBHP) as oxidising agent. Spinel oxide catalyst was characterized by different techniques such as X-ray diffraction (XRD), N-2 adsorption-desorption, BET surface area, and X-ray photoelectron spectroscopy (XPS) to understand the structural, physical properties and oxidation state of the catalyst. The result shows that catalyst prepared by sol-gel method was found higher surface area and smaller crystalline size than co-precipitation method. XPS data confirm the formation of Cu2+ in the spinel which helps to improve the catalytic activity of oxidation. This reaction follows radical mechanism, and exhibited 76.7 \% of CnOH conversion and 68.4 \% of CnHO, and 24.8 \% benzaldehyde (benzald) selectivity using TBHP at 60 degrees C. Kinetic data reveal that 41.2 kJ/mol of activation energy for the reaction. The higher activity of spinel oxide catalyst could be due synergetic effect of spinel (88 \%) and oxides (12 \%) formed in the catalyst, which helps to provide the oxygen during reaction. The contribution of Cu2+ is higher in sol-gel than co-precipitation, which may provide the better reactivity of catalyst. This work helps to select the effective and cost-effective catalyst for the oxidation of CnOH.

}, keywords = {Catalysts, Cinnamaldehyde, Cinnamyl Alcohol, Cupper, iron, oxide, spinel}, issn = {2365-6549}, doi = {10.1002/slct.202104441}, author = {Dange, Rutvija M. and Niphadkar, Prashant S. and Bokade, Vijay V. and Nandanwar, Sachin U.} } @article {48156, title = {Influence of catalyst reduction temperature on autogenous glycerol hydrogenolysis over NiAl catalyst}, journal = {Asian Journal of Organic Chemistry}, volume = {11}, year = {2022}, month = {FEB}, pages = {e202100704}, type = {Article}, abstract = {

Autogenous glycerol hydrogenolysis to 1,2-propanediol by aqueous phase reforming (APR) was investigated over supported nickel catalysts. Effect of reduction temperature on physico-chemical properties of catalysts played a significant role in tuning conversion and product selectivities. The formation of nickel aluminate (NiAl2O4) spinel phase during catalyst reduction led to rearrangement of Ni species to obtain small and stable Ni particles. The catalyst activation temperature alters the extent of reduction of multivalent Ni species (Ni-0, Ni+2/+3) which facilitated glycerol dehydration and hydrogenation while suppressing C-C cleavage and thus avoiding undesirable side products. Additionally, presence of moderate Bronsted/Lewis acid ratio of the catalyst promoted higher 1,2-PDO selectivity. In-situ glycerol hydrogenolysis involves glycerol dehydration to acetol with simultaneous reforming to H-2 and CO2 and this hydrogen converts acetol to 1,2-PDO.

}, keywords = {APR, autogenous hydrogenolysis, Glycerol, Propanediols, reduction temperature, spinel}, issn = {2193-5807}, doi = {10.1002/ajoc.202100704}, author = {Pandya, Rajan and Mane, Rasika and Rode, Chandrashekhar} }