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Structural Study of a Benzidine-Vermiculite Intercalate Having a High Tetrahedral-Iron Content by 57Fe Mossbauer Spectroscopy
Benzidinium ion Intercalate Iron Mossbauer spectra Vermiculite
2012/1/10
57Fe Mössbauer spectra obtained at room temperature and 78 K for natural Mg-saturated, Ca-saturated, and benzidinium-intercalated vermiculite having a high tetrahedral iron content are presented....
Relation between Structural Disorder and Other Characteristics of Kaolinites and Dickites
Crystallinity Dickite Disorder Electron paramagnetic resonance Fourier-transform infrared spectroscopy Kaolinite
2012/1/11
A suite of Georgia kaolinites, ranging from well-ordered to very poorly ordered samples, were studied to explore correlations between degree of structural disorder, geological environment, Fe3+ conten...
Role of Structural Hydrogen in the Reduction and Reoxidation of Iron in Nontronite
Hydrogen Nontronite Oxidation Reduction Structural sites Tritium
2012/2/2
The effects of reduction and reoxidation of octahedral Fe3+ on the exchange of structural hydrogen in nontronite were determined using tritium (3H) as a label element. The uptake of H from the surroun...
Single crystals of sudoite from Ottré, Belgium, allow confirmation of a dioctahedral 2:1 layer and a trioctahedral interlayer in a IIb arrangement. A regular 2-layer s structure is formed in which the...
Structural Studies of Nontronites with Different Iron Contents by 57Fe Mossbauer Spectroscopy
Interlayer cation Iron Mossbauer spectroscopy Nontronite Structural sites
2012/2/1
The 57Fe M鰏sbauer spectra of a series of untreated and Ca-saturated nontronites showed a predominant Fe3+ resonance which was computer-fitted with two Fe3+ doublets defining iron in non-equivalent cis...
Effects of Reduction and Reoxidation of Structural Iron on the Surface Charge and Dissolution of Dioctahedral Smectites
Dissolution Iron Nontronite Oxidation Reduction Smectite Surface area
2012/2/6
The effect of Fe oxidation state on the surface charge (CEC) and solubility of smectites were studied using the <2-祄, Na+-saturated fraction of an Upton, Wyoming; a Czechoslovakian; and a New Zealand ...
Mossbauer Effect Studies of Iron in Kaolin. I. Structural Iron
Iron Kaolinite Mossbauer effect Paramagnetism Structural substitution
2012/2/7
57Fe M鰏sbauer spectra of a cleaned Weipa, Australia, kaolin showed that a considerable fraction of the structural iron exhibits paramagnetic relaxation between 4癒 and 300癒 the first time that this has...
Oxidation and Reduction of Structural Iron in Chlorite at 480癈
Chlorite Infrared spectroscopy Iron Mossbauer spectroscopy Oxidation Reduction
2012/2/7
An iron-rich chlorite, ripidolite, was oxidized by air-heating at 480?i.e., below the dehydroxylation temperature and subsequently reduced in hydrogen at the same temperature. On the basis of chemical...
Structural Model for Benzidine-Vermiculite
Benzidine Hydrogen bonding Intercalation Vermiculite X-ray diffraction
2012/2/7
A combination of X-ray diffraction, infrared, and chemical data has established that the ion exchange of vermiculite with singly charged benzidine cations in an aqueous solution at pH 1.6 results in a...
Catalytic Action of Copper on the Oxidation of Structural Iron in Vermiculitized Biotite
Biotite Catalyst Copper Iron Oxidation Vermiculite
2012/2/7
The ferrous iron content of two vermiculitized biotites decreased by treatment with 0.1 N salts of copper at 70°C from 9.1–14% to 1.8–2.6%. Presumably, interlayer copper ions acted as a catalyst (here...
STABILITY OF PARATHION ON ATTAPULGITE AS AFFECTED BY STRUCTURAL AND HYDRATION CHANGES
Attapulgite Dehydration Infrared spectroscopy Isomerization Parathion Scanning electron microscopy Thermal treatment
2011/11/15
Abstract--The structure and hydration status of attapulgite clay after heating at elevated temperatures and the stability of parathion on these clays was studied. Using infrared spectroscopy and scann...
Thermodynamic and Structural Features of Water Sorption in Zeolites
Heulandite Stilbite Thermal stability Water sorption Zeolite
2012/2/10
The water adsorption capacity of zeolites is a function of pressure and temperature. Desorption of zeolites may be of three types, wherein the crystal lattice undergoes (1) no or little change, (2) a ...
Reactivity of Adsorbed and Structural Iron in Hectorite as Indicated by Oxidation of Benzidine
Adsorbed Iron Benzidine Catalysis Electron Transfer Hectorite Oxidation
2012/2/9
The roles of different forms of Fe(III) impurities in a hectorite with respect to the oxidation of benzidine in aqueous suspension have been evaluated using electron spin resonance and UV-visible spec...
Determination of Structural Defects in Phyllosilicates by X-Ray Powder Diffraction—II. Nature and Proportion of Defects in Natural Kaolinites
Structural Defects Phyllosilicates X-Ray Powder Diffraction Natural Kaolinites
2012/2/13
Until now, the different attempts to describe the defects of kaolinites were based on the ideas that (i) the hkl reflections with k = 3n are Bragg reflections, while (ii) the hkl reflections with k ≠ ...
Determination of Structural Defects in Phyllosilicates by X-Ray Powder Diffraction—I. Principle of Calculation of the Diffraction Phenomenon
Determination Structural Defects Phyllosilicates X-Ray Powder Diffraction
2012/2/13
This paper describes the calculation of the diffracted intensity for models of powdered minerals with lamellar structure, in order to compare experimental and theoretical X-ray diagrams. The calculati...
