کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1404381 | 1501902 | 2007 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Influence of copper ions on the precipitation of goethite and hematite in highly alkaline media
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
The effects of Cu-dopant on the precipitation of α-FeOOH and α-Fe2O3 particles in highly alkaline media were investigated using 57Fe Mössbauer and Fourier transform infrared (FT-IR) spectroscopies and thermal field emission scanning electron microscopy (FE SEM). Only α-(Fe, Cu)OOH solid solutions were obtained between r = 0.0099 and 0.0291, where r = [Cu]/([Cu] + [Fe]). A mixture of α-(Fe, Cu)OOH and α-(Fe, Cu)2O3 solid solutions was obtained between r = 0.0385 and 0.0566, whereas only an α-(Fe, Cu)2O3 solid solution was obtained between r = 0.0698 and 0.1666. Cu-substitutions in α-(Fe, Cu)OOH and α-(Fe, Cu)2O3 decreased the hyperfine magnetic field ãBhfã values. With increased Cu-substitution in an α-FeOOH type structure the IR shifts were observed. With an increased r value of initial solution a gradual elongation of α-(Fe, Cu)OOH particles along the crystallographic c-axis was observed. At r = 0.0476, some α-(Fe, Cu)OOH particles were â¼700 nm long, and correspondingly the width and thickness of these particles decreased markedly. With a further increase in r the length of α-(Fe, Cu)OOH particles decreased. α-(Fe, Cu)2O3 particles showed varying sizes in dependence on the precipitation conditions, whereas their geometrical shapes matched those typical of α-Fe2O3.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure - Volumes 834â836, 27 May 2007, Pages 154-161
Journal: Journal of Molecular Structure - Volumes 834â836, 27 May 2007, Pages 154-161
نویسندگان
Stjepko Krehula, Svetozar MusiÄ,