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221.
Anoop Kelkar Amrit Prakash Mohd. Afzal J. P. Panakkal H. S. Kamath 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):595-601
A single-column ion chromatography (SCIC) for the simultaneous determination of alkali, alkaline earth and transition metal
elements in UO2, ThO2 powders and sintered (Th, U) O2 pellet is described in this paper. Metrosep cation 1-2 analytical column containing poly butadiene-maleic acid (PBDMA) coated
silica has been applied to the ion chromatographic separation of 12 cations (copper, lithium, sodium, ammonium, nickel, potassium,
zinc, cobalt, manganese, magnesium, calcium and strontium) using an isocratic elution with tartaric acid and oxalic acid as
mobile phase with non-suppressed conductivity detection. Mobile phase composition was optimized to 1 mM tartaric acid and
0.75 mM oxalic acid for the baseline separation of 12 cations. The calibration plots were linear in the range of 0.05–40 mg L−1 with regression coefficients better than 0.998. The relative standard deviations (RSDs) of the retention time, peak area
and peak height were less than 1, 2.8 and 3.0%, respectively. The recoveries of the spiked samples for the cations were 94–110%.
The method developed was validated by comparison with certified standards of UO2 and ThO2 powders. 相似文献
222.
A series of 1,4-dihydropyridines have been prepared by a one-pot condensation of aldehydes,ethyl acetoacetate,and ammonium acetate in the presence of a heterogeneous catalyst silica sulfuric acid at room temperature under solvent-free condition. This new protocol has the advantage of short reaction time and excellent yields,and is an environmentally benign route to the synthesis of 1,4-dihydropyridines. 相似文献
223.
David M. Haddleton Alex M. Heming Adam P. Jarvis Afzal Khan Andrew Marsh Sebastien Perrier Stefan A.F. Bon Stuart G. Jackson Ryan Edmonds Elizabeth Kelly Dax Kukulj Carl Waterson 《Macromolecular Symposia》2000,157(1):201-208
The use of copper(I) Schiff base complex catalysed atom transfer polymerisation of methacrylates is described. The use of a range of functional and multi‐functional initiators enables the synthesis of a range of functional and star polymers to be prepared under undemanding synthetic conditions. End capping with silyl enol ethers allows for ω‐functional polymers. The combination of novel initiators, functional monomers and end capping allows an unprecedented array of macromolecular structures to be produced with limited need for protecting group chemistry. 相似文献
224.
Hassan Haseebul Iqbal Muhammad Waqas Afzal Amir Muhammad Asghar Mazia Aftab Sikandar 《Journal of Solid State Electrochemistry》2023,27(1):125-137
Journal of Solid State Electrochemistry - A hybrid supercapacitor, also known as a supercapattery, combines the high power density of supercapacitors with the high energy density of batteries. In... 相似文献