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41.
Akshay Kokil Sethumadhavan Ravichandran Jayant Kumar Ramaswamy Nagarajan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1004-1008
Polymers synthesized from naturally derived monomers are valuable since they decrease the reliance on petroleum based feed stocks. Cashew nut shell oil (CNSL) is a side-product from processing of edible Cashew nuts of Annacardium occidentale. One of the major components of CNSL is cardanol, which is a phenol derivative having an unsaturated pentadecyl substituent in the ‘meta’ position with varying amount of unsaturation (no double bonds to three double bonds). The substituent in the meta position can also be hydrogenated to yield completely saturated hydrogenated cardanol. Cardanol can be utilized to stabilize the dispersions of oil in water and vice versa since it displays amphiphilic behavior owing to the phenolic head and the C15 aliphatic tail. Here we report the horseradish peroxidase (HRP) catalyzed polymerization of cardanol at oil water interface to obtain polycardanol microcapsules. A synthetic analogue of hydrogenated cardanol, 3-pentadecylphenol (3PDP), was also oxidatively polymerized at the oil-water interface to obtain Poly(3-pentadecylphenol) microcapsules. 相似文献
42.
Langang Niu Ramaswamy Nagarajan Dingsong Feng Lynne A. Samuelson 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1983-1990
Main‐chain thermotropic liquid‐crystalline polyesters containing rigid biphenyl mesogens and flexible spacers were synthesized by chemo‐enzymatic route. The enzyme‐catalyzed polymerization showed high regio‐ and chemo‐ selectivity, and is environmentally friendly. The resulting polyesters were characterized with 1H‐NMR, 13C‐NMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and polarized light optical microscopy (POM). 相似文献
43.
Molecular orbital calculations at the DFT-B3LYP/aug-cc-pVDZ level were performed for the possible tautomers of 1-amino-3-nitro-1,2,4-triazol-5-one-2-oxide. We have examined the substitution effects of amino and nitro groups by comparing calculated geometries, relative energies, and electrostatic potentials of model molecules. The optimized structures, vibrational frequencies, and thermodynamic values for triazol-5-one-N-oxides were obtained in their ground state. The results show 1H, 4H tautomers to be most stable. Detonation velocity and detonation pressure were evaluated by the Kamlet and Jacob equations based on the predicted density and the calculated heat of explosion. Explosive properties appear to be promising compared with those of 1,3,5-trinitro-1,3,5-triazine (D = 8.75 km/s, P = 34.7 Gpa) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (D = 8.96 km/s, P = 35.96 Gpa), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (D = 9.20 km/s, P = 42.0 Gpa) and octanitrocubane (D = 9.90 km/s, P = 48.45 GPa). The designed triazol-5-one-N-oxides satisfy the criteria of high energy density materials. 相似文献
44.
45.
Parakkulam Ramaswamy Aravind Lorenz Ratke Matthias Kolbe Gian Domenico Soraru 《Journal of Sol-Gel Science and Technology》2013,67(3):592-600
In present work, we have prepared gels with various compositions of methyltrimethoxysilane—3-(2,3-epoxypropoxy) propyltrimethoxysilane (MTMS-GPTMS) using a two-step acid base sol–gel process. To make a comparative study between the two common drying routes, we prepared gels under supercritical and also under ambient conditions. The density of the supercritically dried hybrid aerogels lies between 0.18 and 0.31 gcm?3, while the density of the ambient dried ones ranges between 0.35 and 0.42 gcm?3. The surface area of MTMS-0.25 GPTMS aerogel dried under supercritical conditions, has been found to be 464 m2 g?1 with a pore volume and average pore diameter of 1.24 cm3 g?1 and 11 nm respectively. The same composition dried under ambient conditions is found to have similar properties i.e. a BET surface area of 439 m2 g?1, pore volume of 1.22 cm3 g?1 and average pore diameter of 11 nm. The aerogels were later pyrolyzed yielding silica/carbon composite aerogels. The pyrolized aerogels possessed a surface area as high as 207 m2 g?1 with a total pore volume of 0.98 cm3 g?1. The pyrolysed aerogels were also calcined to yield carbon free materials. 相似文献
46.
Evolution of coercivity and its angular dependence in CoFe nanostructures subjected to field cooling
G. K. Rajan S. Ramaswamy G. Chandrasekharan D. J. Thiruvadigal 《Surface and interface analysis : SIA》2014,46(2):98-101
Evolution of coercivity and its angular dependence in CoFe nanostructures subjected to field cooling has been investigated in this work. Spherical CoFe grains with an average diameter of 30 nm were grown on a silicon substrate using electron beam evaporation. Further, the as‐deposited sample was subjected to field cooling. The morphology and topography of the sample before and after field cooling were characterized by atomic force microscopy and SEM. Magnetic force microscopy indicated that there is a good uniformity of magnetization throughout the sample after field cooling. Vibrating sample magnetometer measurements indicate that the coercivity in CoFe nanostructures is dependent on shape of the nanostructures. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
47.
48.
Rani Angineni Venkataswamy Perala Ramaswamy Kadari Srilekha Pallati Sreenu Kurra Vithal Muga 《印度化学会志》2022,99(6):100495
One of the well-known ways of increasing the visible light absorption capability of semiconducting materials is cation doping. This study aims to use Gd doping to tailor the bandgap energy of K2Ta2O6 (KTO) for photocatalytic degradation of organic pollutants under visible light irradiation. Accordingly, the parent KTO and Gd-doped KTO with different Gd concentrations (K2-3xGdxTa2O6; x = 0.025, 0.05, 0.075 and 0.1 mol%) were synthesized by hydrothermal and facile ion-exchange methods, respectively. The powder XRD, FT-IR, SEM-EDS, TEM-SAED, N2 adsorption-desorption, XPS, UV–Vis DRS, PL and ESR techniques were used to investigate the effect of Gd dopant concentration on the structural and photocatalytic properties of KTO. The photocatalytic activity of these samples was investigated for the photocatalytic degradation of methylene blue (MB) dye in an aqueous solution at room temperature under visible light irradiation. The experimental results show that all Gd-doped KTO samples exhibit enhanced photocatalytic activity compared with parent KTO toward MB degradation. In particular, Gd-KTO obtained by doping of 0.075 mol% shows the highest photocatalytic activity among the Gd-doped samples and the degradation efficiency of MB was 79% after 180 min of visible light irradiation, which is approximately 1.5 times as high as that by parent KTO (53%). In addition, trapping experiments and electron spin resonance (ESR) analysis demonstrated that the hydroxyl radicals (?OH) have played a crucial role in the photocatalytic degradation of MB. The reusability and stability of Gd doped-KTO with a Gd content of 0.075 mol% against MB degradation were examined for five cycles. Based on the present study results, a visible light induced photocatalytic mechanism has been proposed for Gd0075-KTO sample. 相似文献
49.
Karunanithi Masilan Neethirajan Neethiselvan Robinson Jeya Shakila Arjunan Karthy Ulaganathan Arisekar Nagarajan Muralidharan Thangaraji Ravikumar Balasubramanian Sivaraman Chellapa Kalidas Lakshmanan Ranjith Dhanasekaran Linga prabhu 《印度化学会志》2022,99(3):100376
The study dealt with evolving an artificial fish bait by incorporating bioattractant concentrates derived from seafood processing wastes by enzymatic hydrolysis namely fish waste concentrate (FWC), squid waste concentrate (SWC), and shrimp processing concentrate (SPWC). They were characterized based on amino acid content and presence of different functional groups using FTIR. Among them, SWC was found to have the highest amino acid content of 60.85mg/100 mg followed by FWC (42.21mg/100 mg) and SPWC (24.82mg/100 mg). The developed artificial fish baits were subjected to protein leaching, solubility in seawater besides testing for acceptability by the red snapper. The study revealed that the bait incorporated with SWC at 3% level was found be the most ideal, with the protein leaching rate of 24.82 mg/g/h, solubility rate of 36.6 mg/g/h and the attractability score of 29/30. The amino acid leaching rate was 3.11 mg/h/100 mg and it was found to contain five amino acids such as glycine, proline, glutamic acid, alanine and serine. The study revealed that the hydrolyzed squid waste concentrate can be incorporated at 3% (w/w) with fish gelatin based biomatrix during gelation to prepare artificial bait. 相似文献
50.
We have synthesized a new series of azo‐bis antipyrine derivatives from a one‐pot multicomponent Knoevenagel/Michael addition reaction of antipyrine, with a diversity of azo aldehydes in ethanol and L‐Proline as a catalyst under reflux condition. The anti‐inflammatory activity of the final products was assessed using the inhibition of albumin denaturation technique. Compound 3f showed an inhibitory effect with IC50 values of 3.6 μM with respect to the standard anti‐inflammatory drug Aspirin, with IC50 values of 2 μM. In addition, molecular docking was performed to confirm the in vitro results against the enzymatic inhibition activity of COX‐2 enzymes in which compound 3f showed good binding affinity with an inhibition constant (Ki) of 1.79 nM. 相似文献