An X-Ray Photoelectron Spectroscopic Study of Some Ammonium Uranates

1986 ◽  
Vol 40 (4) ◽  
pp. 519-525 ◽  
Author(s):  
Alan J. Paul ◽  
Peter M. A. Sherwood
Keyword(s):  
Infrared Spectroscopy ◽  
Chemical Composition ◽  
Binding Energy ◽  
Spectroscopic Study ◽  
Uranyl Nitrate ◽  
Nitrate Solution ◽  
Ammonium Ions ◽  
X Ray ◽  
Nitrate Ions ◽  
Direct Titration

X-ray photoelectron and infrared spectroscopy have been used to investigate the chemical composition of some ammonium uranates, all of which were prepared by the direct titration of uranyl nitrate solution with ammonia. Some correlation is found between the U(4f) binding energy and the pH of the solution used to prepare the uranates, and the v3 asymmetric stretching frequency for the uranyl (UO22+) ion. All samples showed the presence of ammonium ions and possibly two types of hydroxide species. Strong retention of nitrate ions was also observed for all samples.

Cation ordering incis-andtrans-vacant dioctahedral smectites and its implications for growth mechanisms

Clay Minerals ◽  
2012 ◽  
Vol 47 (1) ◽  
pp. 105-115 ◽  
Author(s):  
C. Marchel ◽  
H. Stanjek
Keyword(s):  
Infrared Spectroscopy ◽  
Crystal Growth ◽  
Chemical Composition ◽  
Low Temperature ◽  
Fluorescence Analysis ◽  
Cation Ordering ◽  
Growth Mechanisms ◽  
Octahedral Sheet ◽  
X Ray ◽  
Different Types

AbstractDifferent types of dioctahedral smectites (nontronite, beidellite, montmorillonite) were investigated by X-ray fluorescence analysis (XRF) and Fourier transmission infrared spectroscopy (FTIR). Starting with the chemical composition of the octahedral sheet, the occupancies within the octahedral sheet were adjusted by computer simulations to fit the occupancies derived from FTIR. For bothcis-andtrans-vacant smectites the AlAl and FeFe pairs are mainly randomly distributed but seem to be aligned along OH-bonded directions. Relative to the chemical composition, AlFe pairs are enriched incis-vacant smectites and depleted in nontronites. This behaviour can be explained by the necessity to dehydrate and hydrolyse cations when they become incorporated into the structure during crystal growth. The first and second hydrolysis steps are necessary for incorporating cations intrans-vacant smectites, whereas only the first hydrolysis step is necessary forcis-vacant smectites. The corresponding difference in energy may explain why mostlycis-vacant smectites occur in low-temperature environments.

scholarly journals Dehydroxylation of Perlite and Vermiculite: Impact on Improving the Knock-Out Properties of Moulding and Core Sand with an Inorganic Binder

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2946
Author(s):  
Artur Bobrowski ◽  
Karolina Kaczmarska ◽  
Maciej Sitarz ◽  
Dariusz Drożyński ◽  
Magdalena Leśniak ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Chemical Composition ◽  
Thermal Studies ◽  
X Ray Diffraction ◽  
Knock Out ◽  
X Ray ◽  
Strength Tests ◽  
Positive Effect ◽  
Core Sand ◽  
Scanning Electron

The article presents the results of research aimed at examining the type of swelling material introduced into moulding or core sand to improve their knock-out properties. Tests on Slovak perlite ore (three grain sizes), Hungarian perlite ore and ground vermiculite (South Africa) were carried out. For this purpose, thermal and structural analyses (FTIR—Fourier Transform Infrared Spectroscopy), a chemical composition test (XRF-X-Ray Fluorescence), phase analysis (XRD—X-Ray Diffraction), and scanning electron microscopy (SEM—Scanning Electron Microscope) as well as final strength tests of moulding sands with the addition of perlite ore and vermiculite were carried out. The results of thermal studies were related to IR (Infrared Spectroscopy) spectra and XRD diffractograms. It has been shown that the water content in the pearlite ore is almost three times lower than in vermiculite, but the process of its removal is different. Moreover, the chemical composition of the perlite ore, in particular the alkali content and its grain size, may influence its structure. The phenomena of expansion (perlite) and peeling (vermiculite) have a positive effect on the reduction of the final sand strength and eliminate technological inconveniences (poor knocking out) that significantly limit the wide use of moulding sands with inorganic binders.

Optical and valence band studies of ZnP2 thin films

1989 ◽  
Vol 4 (1) ◽  
pp. 185-188 ◽  
Author(s):  
V. Samuel ◽  
V. J. Rao
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Chemical Composition ◽  
Binding Energy ◽  
X Ray Diffraction ◽  
Flash Evaporation ◽  
X Ray ◽  
Direct Band Gap ◽  
Direct Band ◽  
Evaporation Technique

Conditions have been developed for the preparation of ZnP2 and deposition of its stoichiometric thin films, using the flash evaporation technique. Structural properties of the ZnP2 obtained have been studied using x-ray diffraction, and chemical composition has been established by the polarography technique. Optical absorption of thin films of β–ZnP2 has been investigated over the range 1.2–3.2 eV. Analysis of thin film data showed that β–ZnP2 is a direct band gap material. The XPS and UPS of β–ZnP2 show a shift in binding energy (BE), which is due to transfer of electrons from zinc to phosphorus.

Spectroscopic Study of Titanium Oxide Thin Films at Low Temperatures by X-ray Diffraction, Raman Scattering, Fourier Transform Infrared Spectroscopy and Photoluminescence

2006 ◽  
Vol 928 ◽  
Author(s):  
Zhiwei Zhao ◽  
Beng Kang Tay
Keyword(s):  
Thin Films ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Spectroscopic Study ◽  
Titanium Oxide ◽  
Low Temperatures ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Oxide Thin Films ◽  
X Ray

ABSTRACTTitanium oxide thin films were prepared by filtered cathodic vacuum arc (FCVA) at low temperatures ranged from room temperature to 330°C. Spectroscopic study of the deposited films were carried out by X-ray diffraction, Raman Scattering, Fourier transform infrared spectroscopy (FTIR) and photoluminescence (PL), respectively. The films remained amorphous up to the substrate temperature of 230°C. Nanocrystalline titanium oxide thin films occurred at 330°C with the strongest peak intensity from anatase (101) plane. The average grain size was around 20 nm and no rutile phase could be found. Various allowed vibrational frequencies (e.g. 152, 199, 399, 640 cm−1) in Raman spectra and Ti-O-Ti transverse mode at 436 cm−1 in the FTIR spectrum evidently verified the presence of anatase phase in the films at 330°C. Moreover, at room temperature only crystalline film exhibited a PL peak with the center at 379 nm in PL spectrum and the origin was discussed.

X-ray photoelectron and auger spectroscopic study of the chemical composition of BC x N y films

2012 ◽  
Vol 53 (4) ◽  
pp. 699-707 ◽  
Author(s):  
V. G. Kesler ◽  
M. L. Kosinova ◽  
Yu. M. Rumyantsev ◽  
V. S. Sulyaeva
Keyword(s):  
Chemical Composition ◽  
Spectroscopic Study ◽  
X Ray

OPTICAL TRANSITION OF POROUS SILICON PREPARED AT DIFFERENT ANODIZATION TEMPERATURES

2009 ◽  
Vol 16 (03) ◽  
pp. 351-354
Author(s):  
LIKUN PAN ◽  
HAIBO LI ◽  
ZHUO SUN ◽  
CHANGQING SUN
Keyword(s):  
Critical Temperature ◽  
Binding Energy ◽  
Porous Silicon ◽  
Spectroscopic Study ◽  
Optical Transition ◽  
Energy Transition ◽  
Blue Shift ◽  
Red Shift ◽  
X Ray

Photoluminescence, photoabsorption, and X-ray photoelectron spectroscopic study revealed that an optical transition of porous silicon from red-shift to blue-shift, and Si -2p binding energy transition from low to high at a critical anodization temperature, 343 K. Possible origin for the reverse variations happening at temperature below and above the critical temperature is discussed.

scholarly journals Новые находки цеолитов на Карадаге

2021 ◽  
pp. 67-75
Author(s):  
А. И. Тищенко ◽  
А. В. Касаткин ◽  
Е. А. Шибаев
Keyword(s):  
Infrared Spectroscopy ◽  
Chemical Composition ◽  
Microprobe Analysis ◽  
Spectroscopy Data ◽  
X Ray Diffraction ◽  
X Ray

The paper reports on the first find of several minerals of Zeolite group in Karadag – heulandite-Na, clinoptilolite-Са, clinoptilolite-Na, stellerite, stilbite-Na, erionite-Ca, erionite-Na. The above minerals were identified by microprobe analysis, X-ray diffraction and infrared spectroscopy. Data on their morphology, chemical composition and paragenesis are given.

Gem-quality garnets: correlations between gemmological properties, chemical composition and infrared spectroscopy

2007 ◽  
Vol 30 (5) ◽  
pp. 307-319
Author(s):  
Ilaria Adamo ◽  
Alessandro Pavese ◽  
Loredana Prosperi ◽  
Valeria Diella ◽  
David Ajó
Keyword(s):  
Infrared Spectroscopy ◽  
Chemical Composition
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