HYDROXY ALUMINUM SULFATE–MONTMORILLONITE COMPLEX

1972 ◽  
Vol 52 (2) ◽  
pp. 209-218 ◽  
Author(s):  
H. KODAMA ◽  
S. SHAH SINGH
Keyword(s):  
Infrared Absorption ◽  
Aluminum Sulfate ◽  
Structural Formula ◽  
Atomic Ratio ◽  
Silicate Layer ◽  
Structural Units ◽  
X Ray ◽  
Wide Range ◽  
Moist Condition ◽  
Basic Aluminum

The nature of the complex that had been formed by precipitating aluminum hydroxide between interlayer spaces of montmorillonite in the presence of anions Cl and SO4 was examined by chemical, X-ray, thermal, and infrared absorption methods. Results indicated that the complex was a hydroxy aluminum sulfate–montmorillonite with the structural formula: Al0.02(H2O)3[Al(OH)2.53(SO4)0.18] + silicate layer of montmorillonite [O10(OH)2 basis]. The atomic ratio, Al:OH:SO4, of the interlayer material was 1:2.53:0.18, which was similar to the ratio 1:2.5:0.25 of "basaluminite." X-ray data showed that the complex had spacings of 19.7, 21.9, and 24.4 A, under an extremely dry condition, moist condition, and on solvation with glycerol, respectively. During the heat treatments between 100 and 200 C, the d001 spacing was sharply reduced to 16 A and the newly developed phase persisted over a wide range of temperature from 200 to 600 C. This phase was considered as an interstratified structure consisting of a 14.3-A unit (chloritelike structure) and a 17.7-A unit (dehydrated basaluminite + silicate layer of montmorillonite). Although the d001 spacing observed for the unheated material was larger than that expected for the amount of aluminum precipitated in the montmorillonite, it was interpreted in terms of voluminous Al13O40 polyhedra that were described previously as basic structural units of a basic aluminum sulfate.

Beidellitic montmorillonite from Swansea, New South Wales

Clay Minerals ◽  
1971 ◽  
Vol 9 (1) ◽  
pp. 107-123 ◽  
Author(s):  
J. D. Hamilton
Keyword(s):  
Coal Seam ◽  
Infrared Absorption ◽  
New South ◽  
New South Wales ◽  
Structural Formula ◽  
X Ray ◽  
South Wales ◽  
Heat Treated ◽  
Saturated Form ◽  
Image Position

AbstractThe minus 1μm fraction of an argillized vitric tuff, overlying the Wallarah Coal Seam near Swansea, N.S.W. is a nearly monomineralic (95%+) expandite clay, which hydrates and reacts to glycerol and heat treatments like montmorillonite. Results of X-ray, differential thermal, thermogravimetric and infrared absorption analyses confirm the general montmorillonoid character of the mineral, but chemical data indicate that much of its structure charge arises from substitutions in the tetrahedral zones of the lattice, as in beidellite rather than montmorillonite. The structural fOrmula deduced for the Ca++-saturated form of the minus 0.1μm clay is:The distinctive behaviours of the heat-treated NH4+- and Li+-saturated structures also suggest that the mineral is a 'beidellitic montmorillonite' rather than a montmorillonite.

Alluaudite-Group Phosphate and Arsenate Minerals

2021 ◽  
Author(s):  
Kimberly T. Tait ◽  
Frank C. Hawthorne ◽  
Norman M. Halden
Keyword(s):  
Single Crystal ◽  
Structural Formula ◽  
Synthesis Methods ◽  
X Ray Diffraction ◽  
Ionic Radii ◽  
X Ray ◽  
International Mineralogical Association ◽  
Graphite Monochromator ◽  
Wide Range

ABSTRACT A systematic study of alluaudite, hagendorfite, and varulite was done using single-crystal X-ray diffraction, powder diffraction, and electron probe microanalysis of samples from 12 separate localities. The crystal structures of the representative alluaudite and hagendorfite samples were refined to R1 indices of 3.7 and 1.8%, respectively, using a Siemens P4 automated four-circle diffractometer equipped with a graphite monochromator and MoKα X-radiation. These samples and several others were analyzed with an electron microprobe to study variations in chemical composition. For the single-crystal analyses, the resulting unit formulae are (Na0.11□0.89)(Na0.59Mn0.27Ca0.14)Mn1.00(Fe3+1.64Al0.24Mg0.13)(PO4)3 for alluaudite, (Na0.79□0.21)(Na0.81Mn2+0.19)(Mn0.70Fe2+0.30)(Fe2+1.72Mg0.27Al0.01)(PO4)3 for hagendorfite, and (Na0.84□0.16)(Na0.71Ca0.23□0.06)Mn1.00(Fe3+0.89Fe2+0.68Mn0.42Mg0.01)(PO4)3 for varulite. Originally, a nomenclature scheme was proposed for the alluaudite-group minerals that was based on sequentially distributing the cations in the cell according to increasing polyhedron size, matching that size with increasing ionic radii of the cations. For alluaudite, the structural formula was written as X(2)4X(1)4M(1)4M(2)8(PO4)12, with the sites ordered in decreasing size of the discrete polyhedra. Later, the formula [A(2)A(2)'A(2)”2][A(1)A(1)'A(1)”2]M(1)M(2)2(PO4)3 was proposed, which takes into account the distinct crystallographic sites in the channels of the structure. More recently there has been a revision to the nomenclature of the group. The simplified structural formula for the alluaudite-type is now A(2)'A(1)M(1)M(2)2(TO4)3; the new nomenclature scheme has been adopted by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA-CNMNC), based on the contents of the M(1) and M(2) octahedral sites, and the results are reviewed here. Compounds belonging to the alluaudite structural family have been the focus of synthetic mineral studies for decades owing to the open-framework architecture and their unique physical properties. Improvements in synthesis methods have allowed researchers to substitute a wide range of elements into the alluaudite structure.

X-Ray Studies in the Ti-O System*

1960 ◽  
Vol 4 ◽  
pp. 175-193 ◽  
Author(s):  
Norman F. H. Bright
Keyword(s):  
Atomic Ratio ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Monoclinic Form ◽  
Wide Range ◽  
Single Well ◽  
Crystalline Forms ◽  
Marked Tendency ◽  
Oxidation Behaviors

AbstractX-ray diffraction studies have revealed that a titanium oxide with an NaCl-type structure is stable over a wide range of nonstoichiometric compositions, both above and below the 1:1 Ti/O atomic ratio. Attempts to prepare a strictly stoichiometric TiO as a single phase have revealed a marked tendency for such a composition to disproportionate into two nonstoichiometric “TiO”-type structures of variable composition, whereas nonstoichiometric compositions can be readily prepared under similar conditions as single, well-crystallized phases.The oxide Ti3O5, which forms a constituent of the titanium-bearing slags produced in ilmenite smelting, has been prepared as a pure compound in two different crystalline forms, both monoclinic in structure, but one being very close to the orthorhombic pseudobrookite, Fe2O3 · TiO2, or ferrous dititanate, FeO · 2TiO2 structure. This “dititanate” form inverts to the other monoclinic form at high temperatures. Single crystals of the latter monoclinic form are readily made. The studies of the “dititanate” form have been restricted to powder diffraction work, since it inverts to the other form after melting. The two forms show different oxidation behaviors,

Investigation of Aluminum Content on the Properties of Sol-Gel-Derived Zinc Oxide Thin Films

2007 ◽  
Vol 561-565 ◽  
pp. 1173-1176
Author(s):  
Shu Wen Xue ◽  
Xiao Tao Zu
Keyword(s):  
Sol Gel ◽  
Optical Transmittance ◽  
Atomic Ratio ◽  
Zno Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Content ◽  
Glass Substrates ◽  
Wide Range ◽  
Sol Gel Process

This paper reports that ZnO:Al films were deposited onto glass substrates by sol-gel process. Al/Zn atomic ratio varied in a wide range from 0 ~ 20%. The structural and optical properties were investigated by X-ray diffraction (XRD) and optical transmittance, respectively. X-ray photoemission spectroscopy (XPS) was used to investigate the elemental compositions. XRD results showed that ZnO films remained c-axis-orientated when Al/Zn atomic ratio was below 20% and the grain size decreased with increasing Al content. The optical transmittance showed that the optical bandgap of ZnO films blueshifted with increasing Al/Zn atomic ratio from 0-20%. XPS measurements showed that the binding energy of O1s increased with increasing Al content.

Analytical electron microscopy of zeolites

1983 ◽  
Vol 41 ◽  
pp. 344-345
Author(s):  
C. E. Lyman
Keyword(s):  
Catalytic Properties ◽  
Selective Adsorption ◽  
Analytical Electron Microscopy ◽  
Atomic Ratio ◽  
X Ray ◽  
Wide Range ◽  
Carbon Coated ◽  
Synthetic Zeolites ◽  
Regular Arrays ◽  
Diamond Knife

Zeolites are crystalline aluminosilicates with regular arrays of uniform pores or channels ranging in size from 0.3nm to l.Onm depending on the specific structure and composition. Synthetic zeolites are an important class of technological materials with a wide range of selective adsorption, ion exchange, and catalytic properties. Catalytic properties of zeolites are often related to the silicon-- ttoo-aluminum atomic ratio; however, conventional microprobe analysis of zeolites has been limited to crystals much larger than the l-5μm size used in practice.Zeolite A is known to have a Si/Al ratio near unity since it contains the maximum aluminum content possible in a tetrahedral aluminosilicate framework. Particles of zeolite Na-A were embedded in epoxy and 80nm-thick sections were cut with a diamond knife and collected on carbon coated Cu grids. Analyses across zeolite particles were performed in a Vacuum Generators HB-501 STEM fitted with a Kevex x-ray detector. Because this material damages in the electron beam, x-ray spectra were taken while scanning the beam in a raster about l00nm x l00nm.

Counterfeit Parts Recognition and Detection for Failure Analysts

2010 ◽  
Author(s):  
Katherine V. Whittington
Keyword(s):  
Thermal Cycle ◽  
Visual Inspection ◽  
Acoustic Microscopy ◽  
Scanning Acoustic Microscopy ◽  
3D Measurement ◽  
X Ray ◽  
Wide Range ◽  
Electronic Parts ◽  
Testing Awareness

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.

scholarly journals Characterization and mapping of hematite ore mineral classes using hyperspectral remote sensing technique: a case study from Bailadila iron ore mining region

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Ibrahim Shaik ◽  
S. K. Begum ◽  
P. V. Nagamani ◽  
Narayan Kayet
Keyword(s):  
Infrared Absorption ◽  
Near Infrared ◽  
Spectral Feature ◽  
Absorption Feature ◽  
X Ray ◽  
Remote Sensing Technique ◽  
Ore Minerals ◽  
Feature Fitting ◽  
Hematite Ore

AbstractThe study demonstrates a methodology for mapping various hematite ore classes based on their reflectance and absorption spectra, using Hyperion satellite imagery. Substantial validation is carried out, using the spectral feature fitting technique, with the field spectra measured over the Bailadila hill range in Chhattisgarh State in India. The results of the study showed a good correlation between the concentration of iron oxide with the depth of the near-infrared absorption feature (R2 = 0.843) and the width of the near-infrared absorption feature (R2 = 0.812) through different empirical models, with a root-mean-square error (RMSE) between < 0.317 and < 0.409. The overall accuracy of the study is 88.2% with a Kappa coefficient value of 0.81. Geochemical analysis and X-ray fluorescence (XRF) of field ore samples are performed to ensure different classes of hematite ore minerals. Results showed a high content of Fe > 60 wt% in most of the hematite ore samples, except banded hematite quartzite (BHQ) (< 47 wt%).

scholarly journals Preparation of Synthetic Zeolites from Coal Fly Ash by Hydrothermal Synthesis

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1267
Author(s):  
David Längauer ◽  
Vladimír Čablík ◽  
Slavomír Hredzák ◽  
Anton Zubrik ◽  
Marek Matik ◽  
...  
Keyword(s):  
Fly Ash ◽  
Coal Combustion ◽  
Power Plants ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Product Analysis ◽  
Coal Combustion Products ◽  
X Ray ◽  
Wide Range ◽  
Silica Alumina

Large amounts of coal combustion products (as solid products of thermal power plants) with different chemical and physical properties cause serious environmental problems. Even though coal fly ash is a coal combustion product, it has a wide range of applications (e.g., in construction, metallurgy, chemical production, reclamation etc.). One of its potential uses is in zeolitization to obtain a higher added value of the product. The aim of this paper is to produce a material with sufficient textural properties used, for example, for environmental purposes (an adsorbent) and/or storage material. In practice, the coal fly ash (No. 1 and No. 2) from Czech power plants was firstly characterized in detail (X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX), particle size measurement, and textural analysis), and then it was hydrothermally treated to synthetize zeolites. Different concentrations of NaOH, LiCl, Al2O3, and aqueous glass; different temperature effects (90–120 °C); and different process lengths (6–48 h) were studied. Furthermore, most of the experiments were supplemented with a crystallization phase that was run for 16 h at 50 °C. After qualitative product analysis (SEM-EDX, XRD, and textural analytics), quantitative XRD evaluation with an internal standard was used for zeolitization process evaluation. Sodalite (SOD), phillipsite (PHI), chabazite (CHA), faujasite-Na (FAU-Na), and faujasite-Ca (FAU-Ca) were obtained as the zeolite phases. The content of these zeolite phases ranged from 2.09 to 43.79%. The best conditions for the zeolite phase formation were as follows: 4 M NaOH, 4 mL 10% LiCl, liquid/solid ratio of 30:1, silica/alumina ratio change from 2:1 to 1:1, temperature of 120 °C, process time of 24 h, and a crystallization phase for 16 h at 50 °C.

scholarly journals Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  
Keyword(s):  
Water Content ◽  
Coordination Polymers ◽  
Metal Ion ◽  
Low Cost ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

scholarly journals Synthesis and Advanced Characterization of Polymer-Protein Core-Shell Nanoparticles

Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 730
Author(s):  
Erik Sarnello ◽  
Tao Li
Keyword(s):  
Particle Size ◽  
Small Angle ◽  
Core Shell ◽  
Assembly Process ◽  
Shell Nanoparticles ◽  
X Ray ◽  
X Ray Scattering ◽  
Wide Range ◽  
Core Shell Nanoparticles ◽  
Ray Scattering

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.

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