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Studies on the effects of iron and nickel incorporation into the hydrothermal synthesis of ANA zeolite were carried out. The presented work reveals that pure Fe‐Al analcime is synthesized by using starting composition with a higher iron(III) content than reported in previous publications. Furthermore, the iron(III) and nickel(II) contents play important roles in the framework of the synthesized zeolite. XRD, FT‐IR spectroscopy, diffuse reflectance UV/Vis spectroscopy, nitrogen adsorption and SEM were used to characterize the synthesized zeolites. These investigations showed that loading of iron and nickel ions in ANA zeolite changes the pore size and morphology of analcime zeolite. 相似文献
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Bahram Mokhtari Kobra Pourabdollah Naser Dalali 《Journal of inclusion phenomena and macrocyclic chemistry》2011,69(1-2):1-55
Calixarenes, as nano-baskets, are considered an important group of macrocycles as the third famous host molecules after cyclodextrins and crown ethers have been subject to extensive researches in construction of many extractants, transporters, stationary phases, electrode ionophores and optical and electrochemical sensors over the past four decades. Because of the recent rapid growth in the publications of calixarene applications, this review paper has focused on different analytical applications of calixarenes in the main fields of separation, electroanalysis, spectroscopy and chemometrics. The objectives and the results of about 300 references mainly were published in recent 6 years with emphasis on the analytical applications were reviewed. 相似文献
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Abdolraouf Samadi-Maybodi Robin K. Harris S. Naser Azizi Alan M. Kenwright 《Magnetic resonance in chemistry : MRC》2001,39(8):443-446
Silicon-29 NMR spectra were obtained for more than 20 aqueous alkaline silicate solutions containing methanol. A signal assigned to CH3OSi(OH)3 or one of its deprotonated congeners was studied in detail for the first time for the solution conditions involved. Its appearance was monitored as a function of the solution compositions. The pseudo-equilibrium constant for its formation is of the order of 0.65. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Dilawar Hassan Ali Talha Khalil Amber Rehana Solangi Ahmed El‐Mallul Zabta Khan Shinwari Malik Maaza 《应用有机金属化学》2019,33(8)
We report an eco‐friendly synthesis of α‐Cr2O3 nanoparticles (NPs) using Callistemon viminalis (Bottle Brush) flower extracts as an efficient reducing and capping agent. NPs of sizes 15 nm and 17 nm were synthesized by annealing them at 400°C and 500°C, respectively, which were characterized by X‐ray diffraction, UV–Vis, Fourier transform‐infrared, high‐resolution‐transmission electron microscopy/scanning electron microscopy, SAED, energy‐dispersive X‐ray spectroscopy and SQUID. Microplate‐based assay was used for examining antibacterial potential against 12 pathogenic bacterial strains, and their minimum inhibitory concentrations were calculated. MTT cytotoxic assay was accomplished on Leishmania tropica amastigotes and promastigotes, which revealed IC50 values of 44 μg/ml and 10.56 μg/ml, respectively. An IC50 value of 46.32 μg/ml was obtained for HepG2 cancer cells. Enzyme inhibition studies indicated good acetylcholinesterase, moderate butyrylcholinesterase and low alpha‐glucosidase inhibition. Hemolytic assay indicated hemocompatibility at low concentration. In addition, good DPPH radical scavenging and moderate reducing power and total antioxidant potential was revealed by α‐Cr2O3 NPs. 相似文献
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Pentafluorophenylammonium triflate(PFPAT) was found to be a highly efficient catalyst for the preparation of 2,4,6- triarylpyridines from the reaction of acetophenone derivatives,aromatic aldehydes and ammonium acetate.Present methodology offers several advantages,such as short reaction time,high yields,simple procedure with an easy work-up and the absence of any volatile and hazardous organic solvent.In addition,this catalytic system can act as an active,inexpensive,metal-free,recoverable and recyclable catalyst. 相似文献
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Amin Aziznia Hamid Reza Bozorgzadeh Naser Seyed-Matin Morteza Baghalha Ali Mohamadalizadeh 《天然气化学杂志》2012,(4):466-475
In the current study,the hybrid effect of a corona discharge and γ-alumina supported Ni catalysts in CO2 reforming of methane is investigated.The study includes both purely catalytic operation in the temperature range of 923-1023K,and hybrid catalytic-plasma operation of DC corona discharge reactor at room temperature and ambient pressure.The effect of feed flow rate,discharge power and Ni/γ-Al2O3 catalysts are studied.When CH4/CO2 ratio in the feed is 1/2,the syngas of low H2/CO ratio at about 0.56 is obtained,which is a potential feedstock for synthesis of liquid hydrocarbons.Although Ni catalyst is only active above 573K,presence of Ni catalysts in the cold corona plasma reactor(T≤523K) shows promising increase in the conversions of methane and carbon dioxide.When Ni catalysts are used in the plasma reaction,H2/CO ratios in the products are slightly modified,selectivity to CO increases whereas fewer by-products such as hydrocarbons and oxygenates are formed. 相似文献