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81.
Polysiloxane-encapsulated "Pd"-nanoclusters were generated by reduction of Pd(OAc)(2) with polymethylhydrosiloxane, which functions as a reducing agent as well as a capping material for production and stabilization of catalytically active "Pd"-nanoparticles. Chemoselective hydrogenation of functional conjugated alkenes was achieved by in-situ- or ex-situ-generated polysiloxane-stabilized "Pd"-nanoclusters under mild reaction conditions in high yields. Electron microscopy, UV-vis, and NMR studies of the reaction mixture during the catalytic transformation were performed and, in conjunction with catalyst poisoning experiments, demonstrated unequivocally the role of polysiloxane-encapsulated "Pd"-nanoclusters as the real catalytic species. The recyclability of the "Pd"-nanoclusters was established by reusing the solid left after the reaction. 相似文献
82.
Debajyoti Choudhury Rahul Sinha S Arunagiri Gautam Bhattacharyya Debrupa Chakraverty Debajyoti Choudhury Amitava Datta Anindya Datta Aseskrishna Datta Amol Dighe Dilip Kumar Ghosh Anjan Giri Stephen King Anirban Kundu Rukmani Mohanta Biswarup Mukhopadhyaya Sreerup Raychaudhuri Saurabh Rindani Probir Roy DP Roy Sourov Roy AI Sanda Nita Sinha Rahul Sinha K Sridhar H Yamamoto 《Pramana》2000,55(1-2):335-345
This report summarises the work done during WHEPP-6 (Institute of Mathematical Sciences, Chennai, India, Jan 3–15, 2000) in
Working group on ‘B and collider physics’. 相似文献
83.
Xiaolan WangRajendra Rathore Ponusa Songtipya Maria del Mar Jimenez-GascoEvangelos Manias Charles A. Wilkie 《Polymer Degradation and Stability》2011,96(3):301-313
Composites of ethylene-vinyl acetate copolymer with two different layered double hydroxides have been obtained by melt blending and these have been characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, thermogravimetric analysis connected to mass spectroscopy and cone calorimetry. There is some small difference in dispersion between the zinc-containing and the magnesium-containing layered double hydroxides in EVA, but both these are microcomposites with good dispersion at the micrometer level and relatively poor dispersion at the nanometer level. There is a good reduction in the peak heat release rate at 10% LDH loading. In addition to chain stripping, which involves the simultaneous loss of both acetate and a hydrogen atom, forming acetic acid, and the formation of poly(ethylene-co-acetylene), side chain fragmentation of the acetate group also occurs and may be the dominant pathway of thermal degradation in the first step. The presence of the LDH causes acetone, rather than acetic acid, to be evolved in the initial step of the degradation. 相似文献
84.
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87.
D. P. S. Rathore 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):745-746
88.
Jigisha Parikh Jitendra Rathore Darshak Bhatt Meghal Desai 《Journal of Dispersion Science and Technology》2013,34(10):1392-1398
The present study investigates the effect of different additives on the cloud point (CP) of nonionic surfactants Triton X-100 (TX-100) and Triton X-114 (TX-114) in aqueous solutions. The thermodynamic parameters of these mixtures were calculated at different additive concentrations. The cloud point of nonionic surfactants TX-100 and TX-114 decreased with the increment of electrolyte concentrations and increased with alcohol concentrations. The standard Gibbs free energy was found to be positive for both the surfactants, whereas the enthalpy and the entropy of the clouding phenomenon were found to be positive with alcohols and negative with electrolytes. The overall clouding process was endothermic for alcohols and exothermic for electrolytes. 相似文献
89.
Santosh K. Sar Rashmi Mandavi Nutan Rathore P. K. Pandey 《Journal of Dispersion Science and Technology》2013,34(9):1288-1290
The hydrolysis of the p-nitrophenyl acetate catalyzed by different hydroxamate ions (RCONHO?; R = C6H5, 2-OHC6H4, CH3) was investigated at 27°C in aqueous media containing polyethylene glycol(MW = 4000 and 8000) at various pH values. Hydroxamate ions are effective alpha effect nucleophile for acylation reactions. Addition of PEG accelerates the rate of hydrolysis. The rate-polymer profile has been explained by applying different models. A mechanism for the catalyzed reaction is proposed. The BHA-PEG combination is more effective. 相似文献
90.
Mahendra Kumar Kailash Sharma Ankur Kumar Fogla Kanika Sharma Madhu Rathore 《Research on Chemical Intermediates》2013,39(6):2555-2564
A new series of structurally diverse 2,3-dihydrobenzo[b][1,4]thiazepines (2,3-dihydro-1,5-benzothiazepines) with substituted phenyl groups at C(2) and C(4) have been synthesized by reaction of 3-(5-bromo-2-methoxyphenyl)-1-arylpropen-1-ones with 2-aminobenzenethiols. The structures of all the synthesized compounds were confirmed by their analytical and spectral data (IR, 1H NMR, 13C NMR). All the synthesized compounds were evaluated for antibacterial and antifungal activity against a variety of bacterial and fungal strains and interesting results were obtained. Some of the compounds had antibacterial and antifungal activity comparable to that of ciprofloxacin and fluconazole. 相似文献