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Reduction of Structural Fe(III) in Smectite by a Pure Culture of Shewanella Putrefaciens Strain MR-1
Clay Fe(III) reduction Metal-reducing bacteria Sediments Smectite Soils
2011/12/27
Abstract: Shewanella putrefaciens is a species of metal-reducing bacteria with a versatile respiratory metabolism. This study reports that S. putrefaciens strain MR-1 rapidly reduces Fe(III) within sm...
In situ 29Si MAS NMR studies of structural phase transitions of tridymite
situ 29Si MAS NMR studies phase transitions tridymite
2012/4/5
The structural phase transitions ofmonoclinic tridymite that occur at elevated temper-atures, as wellas the structure of the high-temperature modifications, have been studied by 29SiMASNMR. The sample...
Structural Transformations of Interstratified Illite-Smectites from Dolná Ves Hydrothermal Deposits: Dynamics and Mechanisms
Cis-octahedron Illite-smectite Illitization Phase Transformations Trans-octahedron
2011/12/23
Abstract: Structural transformations of illite-smectite samples of hydrothermal genesis with increasing contents of illite layers were studied by X-ray powder diffraction. The samples were K-saturated...
Compositional variation and structural state of columbite-tantalite in rare element granitic pegmatites of the Preissac-Lacorne batholith, Quebec, Canada
Compositional variation columbite-tantalite element granitic pegmatites Preissac-Lacorne batholith Quebec Canada
2012/4/5
Rare-element-enriched graniticpegmatitesin andnearthe LamotteandLacorneplutons ofthe ArcheanPreissac-Lacorne batholith (Quebec) arezoned from aleast fractionated beryltype in the parental pluton throu...
Structural relationship between pyrite and marcasite
Structural relationship pyrite marcasite
2012/4/5
Westudied pyrite spherules built of radiating crystals to establish the relationships among microstructure, composition, and macroscopic appearance. Results of high-reso-lution transmission electron m...
An Improved Model for Structural Transformations of Heat-Treated Aluminous Dioctahedral 2:1 Layer Silicates
Beidelites Cis-vacant octahedra Dehydroxylation Illites Montmorillonites Trans-vacant octahedra
2011/12/28
An improved model for the interpretation of thermal effects during dehydroxylation in aluminous dioctahedral 2:1 layer phyllosilicates considers trans-vacant (tv) and cis-vacant (cv) 2:1 layers and le...
Nature of Structural Disorder in Natural Kaolinites: A New Model Based on Computer Simulation of Powder Diffraction Data and Electrostatic Energy Calculation
Energy calculation Kaolinite Layer disorder XRPD simulation
2011/12/28
A new model for the description of the structural disorder in natural kaolinite materials is proposed, based on the stacking of two 1:1 layers and their enantiomorphs, and encompassing previously prop...
FTIR Reflectance vs. EPR Studies of Structural Iron in Kaolinites
EPR Fe Kaolinite Mid and near infrared Substitution
2011/12/29
The substitution of Fe3+ in the kaolinite structure is studied by EPR spectrometry and by FTIR spectrometry on a large set of kaolins from different origins (sedimentary and primary ores, soil kaolins...
A Structural Model for Natural Siliceous Ferrihydrite
Domain size Ferrihydrite Low-angle X-ray diffraction (LAXRD) Particle size Silicate Structure X-ray diffraction (XRD)
2011/12/31
X-ray diffraction of four natural samples of ferrihydrite indicates the presence of crystalline domains within the primary particles. The average diameter of the primary particles (determined from low...
Reduction of Structural Iron in Ferruginous Smectite by Free Radicals
Clay Dithionite Electron spin resonance spectroscopy ESR Hydrazine Iron Reduction Smectite Sulfide Thiosulfate
2011/12/31
The oxidation state of structural iron greatly influences the physical-chemical properties of clay minerals, a phenomenon that may have significant implications for pollutant fate in the environment, ...
Structural Water in Volcanic Glass
Glass Heavy-ion Rutherford scattering High-resolution transmission electron microscopy Structural water
2011/12/1
Abstract: High-resolution transmission electron microscopy has revealed spherical and hemispherical structures on the surface of partly hydrated volcanic and synthetic glasses. These structures contra...
FTIR Study of Deuterated Montmorillonites: Structural Features Relevant to Pillared Clay Stability
Deuterated montmorillonites FITR Pillared smectites Thermal stability
2011/12/1
Abstract: FTIR studies of six partially-deuterated montmorillonites (MS) reveal the presence of two O-D stretching bands, one between 2702–2728 cm-1 and another near 2680 cm-1. For homoionic (Li, Na, ...
Effects of Structural Iron Reduction on the Hydraulic Conductivity of Na-Smectite
Barriers Bulk density Clay Hydraulic conductivity Iron Liners Permeability Reduction Smectite Water
2011/12/31
The long-term impermeability of clay barriers in waste disposal facilities and hydraulic structures is of critical importance to environmental, agricultural, and industrial concerns. Changes in the ox...
Structural Characterisation of Kaolinite:NaCl Intercalate and its Derivatives
FTIR Intercalate Kaolinite NaCl NMR Structure Synthesis XRD
2011/12/31
Kaolinite:NaCl intercalates with basal layer dimensions of 0.95 and 1.25 nm have been prepared by direct reaction of saturated aqueous NaCl solution with well-crystallized source clay KGa-1. The inter...
Structural and Magnetic Properties of Ferrihydrite
Ferrihydrite Ferrimagnetism Antiferromagnetism
2011/12/30
57Fe M鰏sbauer spectra of two synthetic samples of ferrihydrite, recorded at 4.2 K in applied fields of up to 9 T, have been analysed by a mean-field model. The samples exhibit two and six X-ray diffra...