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Structural characterization of iron oxides and hydroxides in the clay fraction of soil from the Inca civilization Moray terraces |
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| รหัสดีโอไอ | |
| Creator | Maria Luisa CERON LOAYZA,Jorge Aurelio BRAVO CABREJOS,Felipe Americo REYES NAVARRO,Rosio ASCUNA ARCONDO |
| Title | Structural characterization of iron oxides and hydroxides in the clay fraction of soil from the Inca civilization Moray terraces |
| Publisher | Metallurgy and Materials Science Research Institute, Chulalongkorn University |
| Publication Year | 2557 |
| Journal Title | Journal of Metals, Materials and Minerals |
| Journal Vol. | 24 |
| Journal No. | 2 |
| Page no. | 41-48 |
| Keyword | Sedimentation method, Selective dissolution techniques, Dithionite-citratebicarbonate,X-ray diffractometry,Iron oxides and hydroxides,Transmission M?ssbauer spectroscopyX-ray diffractometry,Iron oxides and hydroxides,Transmission M?ssbauer spectroscopy |
| ISSN | 8576149 |
| Abstract | We introduce the structural characterization of iron oxides and hydroxides in clay fraction obtainedfrom soil collected in the Inca Moray terraces of Peru. This characterization is important since theseterraces areconsidered as a major advance in the Incacivilization agricultural technology. We have utilized thefollowingtechniques : a selective dissolution bydithionite-citrate-bicarbonate (DCB) and sodium hydroxide(NaOH). Also, it was used analytical X-ray diffractometry (XRD) techniques and transmission M?ssbauerspectroscopy (TMS). XRD of untreated samples showed that all the terraces samples contain quartz andcalcite. After treatment with NaOH and DCB, peaks from quartz kept defined; XRD analysis shows a wellcrystallizedFe3+oxide in all analyzed samples, along with a mixture of quartz, stratified illite-montmorillonitesanidineclay mineral and muscovite. The main peak of gypsum, observed by XRD in untreated samples,dissolved almost completely. In the TMS analysis it is observed efficiency of NaOH to concentrate iron;concerning the DCB treated samples, the area ratio of M?ssbauer absorption indicates an increase of Fe3+ sites.Besides, DCB treatment, sequentially applied four times, dissolved the poorly crystallized hematite.whereby steels containing silicon reacts rapidly with zinc during galvanization. From the microstructural andkinetics analysis, it is found that nickel-phosphorus electroless pre-coatings effectively serve as barriers to thereaction between Fe and Zn during galvanization, regardless of the silicon content in the steel substrates.Correspondingly, the coating thickness of the galvanized steels can be well-controlled. |
