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1.
Catalysts with tunable porosity, crystallinity and acidity can selectively produce aviation fuels and road transportation fuels via hydroprocessing of non-edible oils. Here we discuss several catalyst supports—mesoporous alumina, silica–alumina and hierarchical mesoporous zeolites, developed and used as support for hydroprocessing catalysts (Ni–Mo, Co–Mo, Ni–W), for the selective production of transportation fuels. These developed catalysts were used for the hydroconversion of waste cooking-oil, jatropha-oil, algal-oil and their mixtures with petroleum refinery oils. The physicochemical properties of the catalyst were tuned for optimal performance on the basis of evaluation results on high pressure fixed bed microreactors and pilot scale reactors. These studies targeted the production of transportation fuels (gasoline, kerosene and diesel) by hydroprocessing (hydrotreating or hydrocracking) renewable feed stocks or co-processing with fossil based oils. Modelling and process optimization studies for prediction of kinetic rate parameters and to know the reaction pathways for the conversion of these feed stocks to various range of hydrocarbon fuels, were also carried out. These studies provided the vital information that the reaction pathways were temperature dependent.  相似文献   
2.
We have developed simple, greener, safer multicomponent synthesis series of 4-arylidene-2-phenyl-5(4H) oxazolones 4(a-r) catalyzed by Bronsted acid ionic liquid as triethylammonium hydrogen sulfate [Et3NH][HSO4] and catalytic amount of acetic anhydride and sodium acetate with excellent yields (90–99%). The protocol offers economical, environmentally benign, solvent-free conditions, and recycle–reuse of the catalyst and easily available starting as benzoyl chloride 1, amino acid 2 and a variety of aldehydes 3. The cyclization followed by condensation of benzoyl chloride, amino acid, and a variety of aldehydes catalyzed by ILs [Et3NH][HSO4] and catalytic amount of acetic anhydride and sodium acetate. The final products were confirmed by their characterization data such as FTIR, 1H-NMR, 13C-NMR, Mass, high-resolution mass spectra and were compared with its reported method.  相似文献   
3.
This paper describes a two dimensional matrix memory using ferritecores. A unit consisting of 100 words of 11 binary digits each has been constructed for parallel operation. The word drive is from a biased switch-core matrix, while the digit drive makes use of pulse—trans-formers. Logic and circuit techniques enable high discrimination between wanted and unwanted signals. A semi-automatic method for testing the memory cores is also described  相似文献   
4.
Adenine has been used as the template for the directed synthesis of 5-substituted imidazoles. A Novel intermediate involved in the cyclic operation has been characterised.  相似文献   
5.
Summary The thin-layer chromatographic behaviour of 28 phenolic compounds was studied on semicrystalline stannic tungstate layers using various solvent systems of which formic acid and n-butanol-formic acid were found to be the most useful for the separation of these compounds. Dimethyl sulphoxide was found to act as a self detector for a number of phenols. An interesting feature of the study of phenols using stannic tungstate is the novel separation of different isomeric compounds. A number of binary, ternary and quarternary separations of bioanalytical and immunophysiological importance have been achieved.  相似文献   
6.
Research on Chemical Intermediates - A Brønsted acidic ionic liquid [Bu3NH][HSO4] as an eco-efficient catalyst for the one-pot multicomponent synthesis of...  相似文献   
7.
A new series of 2-(4-(benzo[d]thiazol-5-ylsulfonyl)piperazin-1-yl)-N-substituted acetamide (5a-5k) compounds have been synthesized, and these compounds were characterized with spectral data like IR, NMR, and Mass spectroscopy. All compounds were evaluated in vitro for their efficacy as antimicrobial against Gram-positive and Gram-negative pathogenic bacterial strains such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa using ciprofloxacin as a standard and fungal strains like Candida albicans and Aspergillus fumigatus as compared with standard drug Clotrimazole, and Molecular docking study shows that all these compounds were having good to excellent correlation binding energy as compared with binding energy of standard drugs.  相似文献   
8.
Research on Chemical Intermediates - A novel task-specific ionic liquid, 2-carboxy-N,N-diethylethanaminium acetate denoted as [Et2NH(CH2)2CO2H][AcO], is prepared in an easy process and fully...  相似文献   
9.
Proton–ligand dissociation constant of 1-cyclopropyl-1,4-dihydro-4-oxo-7-(1-piperazinyl) quinolone-3-carboxylic acid is ciprofloxacin and metal–ligand stability constants of its complexes with some metal ions have been determined potentiometrically in the presence of (0.01, 0.02 and 0.03 mol/dm3) NaClO4. The order of the stability constants of the formed complexes increases in the sequence Cu2+, Fe3+, Ni2+ and Zn2+ and decreases with increase in the concentration of ionic strength.  相似文献   
10.
A facile, convenient, environmentally benign, and one-pot synthesis of imidazo[1,2-a]pyridines from 2-aminopyridines and in-situ generated phenacyl bromides under microwave irradiation in polyethylene glycol (PEG-400) and water (1:2) has been developed. The protocol provides a better alternative to the existing method as it involves utilization of in-situ-generated α-bromoacetophenones, avoids the use of lachrymatric α-haloketones as well as volatile toxic organic solvents, and reduces the reaction time to obtain excellent yield.  相似文献   
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