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61.
Pujari Vijay Kumar Vinnakota Srilalitha Kakarla Ramana Kumar Maroju Sreedhar Ganesh Arram Pervaram S. 《Russian Journal of General Chemistry》2018,88(7):1502-1507
Russian Journal of General Chemistry - A novel series of (E)-1-{2/3/4-[(1-aryl-1H-1,2,3-triazol-4-yl)methoxy]phenyl}-3-(2-morpholinoquinolin-3-yl)prop-2-en-1-ones is synthesised from terminal... 相似文献
62.
Polyaniline sulfate‐zeolite composite was prepared by emulsion polymerization. Epoxy resin was cured using polyaniline‐sulfate salt and various amounts of polyaniline sulfate‐zeolite composite. The kinetics of the cure reaction for an epoxy resin based on the diglycidyl ether of bisphenol A (DGEBA) with polyaniline‐sulfate and polyaniline sulfate‐zeolite composite have been studied using differential scanning calorimetry (DSC) under isothermal and dynamic conditions. Isothermal kinetics analysis was performed using the phenomenological model of Kamal. Dynamic kinetic analysis was performed using Kissinger's method. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
63.
Polyaniline supported palladium catalysts were prepared from different palladium precursors and all the catalysts are well characterized using ICP-AES, FTIR, TGA-DTA, SEM-EDX and XPS analysis. All the catalysts were tested for Suzuki-Miyaura coupling of bromo- and chloroarenes in water and the catalyst prepared from PdCl2 precursor was found to be the most effective catalyst. The catalyst can easily be recovered by simple filtration and reused for several cycles with almost consistent activity. 相似文献
64.
Methylthiolation of structurally diverse aryl halides was accomplished under fluoride free conditions using catalytic amounts of CuI, and DMSO as the methylthiolation source. Optimization studies unveiled several varieties of promoters among which Zn(OAc)2 was found ideal. The analogous reaction with DMSO-d6 afforded corresponding deuterated aryl methyl thioether with 99% purity. Mechanistic studies revealed CuSMe as the active methylthiolation agent. 相似文献
65.
66.
The effect of cationic micelles of cetyltrimethylammonium bromide (CTAB) on the kinetics of interaction of copper dipeptide complex [Cu(II)‐Gly‐Gly]+ with ninhydrin has been studied spectrophotometrically at 70°C and pH 5.0. The reaction follows first‐ and fractional‐order kinetics, respectively, in complex and ninhydrin. The reaction is catalyzed by CTAB micelles, and the maximum rate enhancement is about twofold. The results obtained in the micellar medium are treated quantitatively in terms of the kinetic pseudophase and Piszkiewicz models. The rate constants (kobs or kΨ), micellar‐binding constants (kS for [Cu(II)‐Gly‐Gly]+, kN for ninhydrin), and index of cooperativity (n) have been evaluated. A mechanism is proposed in accordance with the experimental results. The influence of different inorganic (NaCl, NaBr, Na2SO4) and organic (NaBenz, NaSal) salts on the reaction rate has also been seen, and it is found that tightly bound/incorporated counterions are the most effective. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 556–564, 2007 相似文献
67.
P. Srihari Dinesh C. Bhunia P. Sreedhar S.S. Mandal J. Shyam Sunder Reddy J.S. Yadav 《Tetrahedron letters》2007,48(46):8120-8124
Aryl propargylic methanols undergo C- and O-nucleophilic substitution reactions in the presence of a catalytic amount of iodine in short reaction times with good yields. 相似文献
68.
Iron chelators have been shown to control the growth of cancer cells in culture by sequestering exogenous iron in the media. Thus, the ligands prevent cellular access to the metal. However, because transferrin provides iron to tumor cells in animals, chelators have not been effective antitumor agents. Polyamine chelator conjugates in which the polyamine vectored ligands into cells were far more active than the free chelators themselves. However, the free ligands were not released from the vector once in the cell. The current study focuses on the synthesis and preliminary evaluation of a polyamine chelator conjugate capable of releasing the free ligand intracellularly via a nonspecific esterase. 相似文献
69.
Pala Rajasekharreddy Pathipati Usha Rani Bojja Sreedhar 《Journal of nanoparticle research》2010,12(5):1711-1721
The development of rapid and ecofriendly processes for the synthesis of silver (Ag) and gold (Au) nanoparticles is of great
importance in the field of nanotechnology. In this study, the extracellular production of Ag and Au nanoparticles was carried
out from the leaves of the plants, Tridax procumbens L. (Coat buttons), Jatropa curcas L. (Barbados nut), Calotropis gigantea L. (Calotropis), Solanum melongena L. (Eggplant), Datura metel L. (Datura), Carica papaya L. (Papaya) and Citrus aurantium L. (Bitter orange) by the sunlight exposure method. Qualitative comparisons of the synthesized nanoparticles between the
plants were measured. Among these T. procumbens, J. curcas and C. gigantea plants synthesized <20 nm sized and spherical-shaped Ag particles, whereas C. papaya, D. metel and S. melongena produced <20 nm sized monodispersed Au particles. The amount of nanoparticles synthesized and its qualitative characterization
was done by UV–vis spectroscopy and transmission electron microscopy (TEM), respectively. X-ray diffraction (XRD) and X-ray
photoelectron spectroscopy (XPS) were used for structural confirmation. Further analysis carried out by fourier transform
infrared spectroscopy (FTIR), provided evidence for the presence of amino groups, which increased the stability of the synthesized
nanoparticles. 相似文献
70.
In this work, we have used a polyaniline and cupric oxide-based nanocomposite material (PANI-CuO) for the adsorption of Pb2+, Cd2+, and Cr6+ ions from contaminated water. FTIR, FESEM, EDX and XRD methods were used in the characterisation of PANI-CuO. The maximum percentage removal of Pb2+, Cd2+, and Cr6+ ions was found to be 79.9%, 78.9% and 82.1% at 1 g of PANI-CuO for 100 mL of contaminated water. The suitability order of the isotherm model was observed as Langmuir > Freundlich > Elovich, whereas the pseudo first order model was best fitted as compared to the pseudo second order model. The rate constants were evaluated as 1.441, 1.801 and 1.661 g mg?1 min ?1, respectively. The values of ΔG0 were calculated to be ?287.4, ?849.6, and ?728.9 kJ mol?1 for Pb2+, Cd2+ and Cr6+ ions, respectively. 相似文献