02677nas a2200253   4500008004100000022001400041245010700055210006900162260009500231300001200326490000800338520173800346653000602084653001402090653002102104653002802125653002102153653002302174653001202197100002502209700003002234700003302264856012602297       2006                        eng d  a0021-951700aSelective ortho-methylation of phenol with methanol over copper manganese mixed-oxide spinel catalysts0 aSelective orthomethylation of phenol with methanol over copper m  a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcOCT  a278-2910 v2433 a<p>Methylation of phenol with methanol as an alkylating agent to produce 2,6-xylenol was investigated over copper manganese mixed oxide spinels, CuxMn3-xO4 (x = 0, 0.25, 0.5, 0.75, and 1) prepared through co-precipitation. The catalytic activity strongly depends on the composition, acid-base properties, and structural stability. Various parameters, including catalyst composition, reaction temperature, feed composition, and durability of the catalyst during methylation, were investigated. Mainly o-cresol and 2,6-xylenol, along with small amounts of mesitol, were found in the product. A high ortho-selectivity of 100%, with 2,6-xylenol selectivity of 74%, was observed over Cu0.25Mn2.75O4 at 673 K. These catalysts were investigated using various techniques, including BET surface area, XRD, DRS UV-vis, TPD of NH3 and CO2, TPR, and X-ray photoemission spectroscopy (XPS). Powder XRD of the catalysts revealed the formation of copper-manganese spinels with hausmannite (Mn3O4) tetragonal structure, for x = 0-0.5, whereas an increase in copper content (x &gt; 0.5) led to the formation of cubic Cu1.5Mn1.5O4 phase. DRS UV-vis, and FTIR further supported the changes in structural phases observed by XRD. Temperature-programmed desorption Of CO2 and NH3 showed that the catalysts have strong basicity along with weak acidity when x = 0 and 0.25. XPS and XAES analysis revealed the presence of only Cu2+ ions in fresh sample with x = 0.25, whereas for x = 1.0, both Cu1+ and Cu2+ were observed. The deactivation of the catalysts is attributed to structural changes occurring during the reaction. Catalytic activity is correlated with structure, as well as with acid-base properties. (c) 2006 Elsevier Inc. All rights reserved.</p>10a210a6-xylenol10aacidity-basicity10acopper-manganese oxides10aortho-alkylation10aphenol methylation10aSpinels1 aReddy, Satyanarayana1 aGopinath, Chinnakonda, S.1 aChilukuri, Satyanarayana, V.  uhttps://library.ncl.res.in/content/selective-ortho-methylation-phenol-methanol-over-copper-manganese-mixed-oxide-spinel-002103nas a2200181   4500008004100000245010500041210006900146260000800215300001000223490000800233520143900241100002201680700001901702700002101721700003301742700001501775856013101790       2017                        eng d00aSignificance of optimal N-doping in mesoporous carbon framework to achieve high specific capacitance0 aSignificance of optimal Ndoping in mesoporous carbon framework t  cOCT  a40-480 v4183 aNitrogen-doped mesoporous carbon (NMC) has been synthesized by sol-gel process using a mixture of phenol and formaldehyde as source of carbon, and melamine as source of nitrogen. The Ludox-AS40 (40 wt% SiO2) is employed, for the first time, as hard template to obtain polymeric gel by prolonged heat treatment at 80 degrees C. The wt% of nitrogen is tuned by varying the weight ratio of melamine to phenol. Stable mesoporous carbon frameworks are obtained by pyrolysis of the dry gel at 800 degrees C in nitrogen atmosphere and treated with alkali to remove silica. One of the carbon framework samples has 11 wt% nitrogen doping and shows pore volume of 0.5 cm(3) g(-1) and surface area 609 m(2) g(-1). The other carbon frame work sample has 6 wt% nitrogen doping and shows higher pore volume of 1.1 cm(3) g(-1) and surface area 736 m(2) g(-1). The later sample exhibits highest electrochemical capacitance of 196 F g(-1) at 0.5 A g(-1) while the former shows only 146 F g(-1) at 0.5 A g(-1). However, both the NMC electrodes show good cyclic performance (91% of the initial capacitance after 1000 cycles) in an aqueous KOH electrolyte. This study demonstrates that there is an optimum level of nitrogen doping required to keep the meso-structure of carbon network intact, simultaneously maintaining high surface area and sufficient electrical conductivity for electrochemical applications. (C) 2016 Elsevier B.V. All rights reserved.1 aSahoo, Malaya, K.1 aGogoi, Pranjal1 aRajeshkhanna, G.1 aChilukuri, Satyanarayana, V.1 aRao, Ranga  uhttps://library.ncl.res.in/content/significance-optimal-n-doping-mesoporous-carbon-framework-achieve-high-specific-capacitance