scholarly journals Regioselective Approach to Characterizing Increased Edge Availability in Layered Crystal Materials following Layer Expansion: Reaction of Kaolinite with Octadecyltrimethylammonium Salts

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 588
Author(s):  
Shingo Machida ◽  
Ken-ichi Katsumata ◽  
Atsuo Yasumori
Keyword(s):  
Fourier Transform ◽  
Mass Loss ◽  
Nitrogen Content ◽  
Infrared Spectra ◽  
Layered Crystal ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermogravimetric Curve ◽  
Diffraction Patterns ◽  
The Fourier Transform

In this paper, the regioselective reactions of kaolinite and methoxy-modified kaolinite (MeO-Kaol), methanol-expanded kaolinite, with octadecyltrimethylammonium salts are compared. This study mainly concerns the reactions of kaolinite or MeO-Kaol with octadecyltrimethylammonium chloride (C18TAC) in methanol and the subsequent exhaustive washing of the resultant products with ethanol. X-ray diffraction patterns of the products reveal no intercalation of C18TAC between pristine kaolinite layers. Additionally, intercalation and subsequent deintercalation of C18TAC proceed in the product using MeO-Kaol. In the Fourier-transform infrared spectra, the intensities of CH2 stretching bands of the product prepared using MeO-Kaol drastically increase compared to those using kaolinite. In addition, CH2 stretching bands of the product using kaolinite are hardly observed without enlarging the spectrum. The product using MeO-Kaol also displays mass loss in the range of 200–300 °C in the thermogravimetric curve and a nitrogen content with 0.15 mass% estimated using the CHN analysis. These results therefore demonstrate an increase in the available reactive edges in the layered crystal material following an expansion of the stacked layers.

Review of the application of ionic liquids as solvents for chitin

2012 ◽  
Vol 32 (2) ◽  
Author(s):  
Malgorzata M. Jaworska ◽  
Tomasz Kozlecki ◽  
Andrzej Gorak
Keyword(s):  
Fourier Transform ◽  
Ionic Liquids ◽  
Microwave Irradiation ◽  
Infrared Spectra ◽  
Elevated Temperatures ◽  
Great Promise ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Crystallinity ◽  
Diffraction Patterns

Abstract Chitin is one of the most abundant biopolymers, but due to its high crystallinity, it is completely insoluble in most organic and inorganic solvents. Chitin is soluble only in solvents that can destroy intersheet and intrasheet H-bonds, and many of these solvents are toxic, corrosive, nondegradable, or mutagenic. Because of these drawbacks, there is a search for more environmentally friendly solvents for chitin. It has been shown that ionic liquids (ILs) can dissolve chitin at elevated temperatures (80°–110°C) or with application of microwave irradiation. The highest solubility of chitin in an IL was about 20% (1-ethyl-3-methylimidazolium acetate), whereas chitin was shown to be insoluble in 1-allyl-3-methylimidazolium chloride and 1-butyl-3-methylimidazolium formate. Dissolved chitin can be regenerated by mixing with water or methanol, where the polymer precipitates from the solution. X-ray diffraction patterns of native polymer and precipitates have been compared and only small changes in crystallinity have been observed. In addition, Fourier transform infrared spectra remained similar for both forms of chitin, native and regenerated. Presented data hold great promise for the improvement of the chemistry of chitin and open new routes for chemical and enzymatic modifications of this polymer.

Infrared spectroscopic study of the YPO4-YCrO4 system

1985 ◽  
Vol 50 (10) ◽  
pp. 2139-2145
Author(s):  
Alexander Muck ◽  
Eva Šantavá ◽  
Bohumil Hájek
Keyword(s):  
Spectroscopic Study ◽  
Infrared Spectra ◽  
Point Of View ◽  
Mixed Crystals ◽  
Crystal Symmetry ◽  
Infrared Spectroscopic Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectroscopic ◽  
Diffraction Patterns

The infrared spectra and powder X-ray diffraction patterns of polycrystalline YPO4-YCrO4 samples are studied from the point of view of their crystal symmetry. Mixed crystals of the D4h19 symmetry are formed over the region of 0-30 mol.% YPO4 in YCrO4. The Td → D2d → D2 or C2v(GS eff) correlation is appropriate for both PO43- and CrO43- anions.

A study of a long-spacing mica-like mineral

Clay Minerals ◽  
1966 ◽  
Vol 6 (4) ◽  
pp. 261-281 ◽  
Author(s):  
W. F. Cole
Keyword(s):  
Fourier Transform ◽  
Layer Structure ◽  
Compositional Variation ◽  
X Ray Diffraction ◽  
Transform Method ◽  
X Ray ◽  
Single Complex ◽  
New Interpretation ◽  
The Fourier Transform ◽  
Diffraction Effects

AbstractAn interstratified clay mineral from Surges Bay, Tasmania, described by Cole & Carthew (1953) as containing a random stacking of illite and montmorillonite in the ratio of 3:2 and a regular stacking of illite and montmorillonite in the ratio of 1 : 1 is re-examined, after purification, and a new interpretation is made of the X-ray diffraction effects in terms of a single complex stacking model. The Fourier transform method of analysis used with an appropriate layer structure factor shows that the interstratification is produced by a three component stacking of 18% single mica layers (A), 10% double mica layers (ĀĀ) and 72% allevardite-like layers (ĀB̄) in which the A and ĀĀ layers are never together. This leads to the conclusion that the near regular interstratification of the mineral is due to structural and/or compositional variation from layer to layer within the parent crystals as suggested by Sudo, Hayashi & Shimoda (1962) to explain similar mineral types occurring in Japan.

Optimization of Stepsize in X-Ray Powder Diffractogram Collection

1988 ◽  
Vol 3 (1) ◽  
pp. 32-38 ◽  
Author(s):  
David G. Cameron ◽  
Ernest E. Armstrong
Keyword(s):  
Fourier Transform ◽  
Fourier Transforms ◽  
X Ray Diffraction ◽  
Step Size ◽  
Reasonable Estimate ◽  
X Ray ◽  
Fourier Transform Methods ◽  
Step Interval ◽  
The Fourier Transform ◽  
Selection Of

AbstractFourier transform methods of smoothing and interpolation are applied to X-ray diffraction data. It is shown that, frequently, too small a step size is used. Major gains are to be expected by selection of the optimum step size and use of these methods.A comparison of Fourier transforms of diffractograms of quartz measured between 67 and 69° 2θ, collected at varying step intervals (0.1 to 0.01° 2θ) was used to illustrate these applications. By examining the Fourier transform of the diffractogram and noting where it decays to die baseline, a reasonable estimate of the optimal step interval can be obtained. In addition, Fourier interpolation can be used to enhance the appearance of the diffractogram, approximating a continuous plot.

A NANOSTRUCTURED POLYMORPH OF μ-OXOBIS(PHTHALOCYANINATOIRON(III)) STUDIED BY ANGULAR AND ENERGY DISPERSIVE X-RAY DIFFRACTION

NANO ◽  
2007 ◽  
Vol 02 (02) ◽  
pp. 121-128 ◽  
Author(s):  
ROBERTO MATASSA ◽  
PAOLO BALLIRANO ◽  
MARIA PIA DONZELLO ◽  
CLAUDIO ERCOLANI ◽  
CLAUDIA SADUN ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Rietveld Method ◽  
Energy Dispersive ◽  
Structural Function ◽  
X Ray Diffraction ◽  
New Approach ◽  
X Ray ◽  
The Fourier Transform

A new approach of X-ray diffraction was used to investigate the nanostructured μ-Oxo(2) polymorph of μ-oxo-bis(phthalocyaninatoiron(III)), [ PcFe – O – FePc ]. The packing of the dinuclear units was determined by the Rietveld method on Angular Dispersive X-ray Diffraction (ADXD) data, whereas the intramolecular geometry was optimized by Energy Dispersive X-ray Diffraction (EDXD) exploiting the peculiar strength of those techniques. The dimension of the nanoparticles was estimated from the Fourier transform of the EDXD experimental structural function.

Röntgen-Beugungsuntersuchungen an Bi-In-Schmelzen / X-Ray Diffraction Experiments with Bi-In-melts

1981 ◽  
Vol 36 (2) ◽  
pp. 150-153 ◽  
Author(s):  
R. Bek ◽  
E. Nold ◽  
S. Steeb
Keyword(s):  
Fourier Transform ◽  
Liquidus Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coordination Numbers ◽  
Structure Factors ◽  
Concentration Dependency ◽  
The Fourier Transform

Abstract Using MoK α-radiation and a θ-θ diffractometer from molten In and Bi as well as six molten Bi-In alloys (8; 22; 27; 33.3; 50; and 77 at % Bi) intensity curves were obtained at 10 °C above the liquidus temperature. The measurements were performed in the q-region up to 14.5 Å-1. From the Fourier transform of the structure factors coordination numbers NItot and radii rItot were obtained. The concentration dependency of NItot and rItot leads to the conclusion, that the Bi-In melts belong to the compound forming melts.

scholarly journals Pitfalls in the Evaluation of X-ray Diffraction Line Shape

1988 ◽  
Vol 41 (2) ◽  
pp. 237 ◽  
Author(s):  
Gerhard Zorn
Keyword(s):  
Fourier Transform ◽  
Computer Simulations ◽  
Line Shape ◽  
Fourier Transformation ◽  
Step Width ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sampling Points ◽  
The Fourier Transform ◽  
Reliable Basis

The sources of errors in the analysis of X-ray diffraction profiles are described, and recipes are given to minimise or eliminate these errors. It is proposed that a sample at high temperatures is used as a standard. The influence of measurement statistics on the Fourier transform of deconvoluted functions is demonstrated through computer simulations. The necessity for smoothing procedures is stressed. It is shown how the parameter step width, number of sampling points, and position of origin for the Fourier transformation can be optimised, and thus a reliable basis can be created for the interpretation of the Fourier transform in terms of crystallite size, size distribution, and micros train.

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