scholarly journals Signatures of technetium oxidation states: a new approach

2020 ◽  
Vol 56 (67) ◽  
pp. 9608-9611
Author(s):  
Stephen Bauters ◽  
Andreas C. Scheinost ◽  
Katja Schmeide ◽  
Stephan Weiss ◽  
Kathy Dardenne ◽  
...  
Keyword(s):  
Oxidation State ◽  
Oxidation States ◽  
General Strategy ◽  
New Approach ◽  
X Ray ◽  
X Ray Absorption

A general strategy for the determination of Tc oxidation state by a new approach involving X-ray absorption near edge spectroscopy (XANES) at the Tc L3 edge is shown.

scholarly journals Probing the variability in oxidation states of magnetite nanoparticles by single-particle spectroscopy

2018 ◽  
Vol 6 (4) ◽  
pp. 875-882 ◽  
Author(s):  
A. Fraile Rodríguez ◽  
C. Moya ◽  
M. Escoda-Torroella ◽  
A. Romero ◽  
A. Labarta ◽  
...  
Keyword(s):  
Oxidation State ◽  
Absorption Spectroscopy ◽  
Magnetite Nanoparticles ◽  
Single Particle ◽  
Cation Distribution ◽  
Oxidation States ◽  
Magnetic Response ◽  
X Ray ◽  
Single Particle Spectroscopy ◽  
X Ray Absorption

Single-particle X-ray absorption spectroscopy reveals that the oxidation state and cation distribution of individual magnetite nanoparticles may be largely heterogeneous even when the macroscopic structural and magnetic response of the ensembles is uniform.

Oxygen Reduction Effect on T’-Pr2-xCexCuO4 Nanopowders in the Underdoped Regime Studied by X-Ray Absorption near Edge Structure

2018 ◽  
Vol 936 ◽  
pp. 93-97 ◽  
Author(s):  
Irfanita Resky ◽  
Putu Eka Dharma Putra ◽  
Triono Bambang ◽  
Saiyasombat Chatree ◽  
Kamonsuangkasem Krongthong ◽  
...  
Keyword(s):  
Oxidation State ◽  
Oxidation States ◽  
Edge Structure ◽  
X Ray ◽  
Reduction Annealing ◽  
Gas Atmosphere ◽  
Reduction Effect ◽  
Ar Gas ◽  
X Ray Absorption ◽  
Cu Ions

This research is aimed to examine oxidation state of Copper (Cu) in both as-synthesized and reduced T’-Pr2-xCexCuO4 (T’-PCCO) with x = 0, 0.10, and 0.15 using Cu K-edge x-ray absorption near edge structure (XANES). The T‘-PCCO nanopowders were successfully synthesized by the chemically dissolved method with HNO3 as a dissolving agent continued by calcination at 1000°C for 15 h. The reduced T’-PCCO nanopowders were obtained by reduction annealing process at 700°C for 5 h under Ar gas atmosphere. The analyses of XANES spectra show that oxidation states of the Cu ions in all of the T'-PCCO nanopowders have values between +1 and +2. This indicates the existence of electron doping in the CuO2 planes, even in the undoped T’-structure. It is found that the oxidation states of the Cu ions change after reduction annealing depending on the existence of apical oxygen in the T'-structure. Based on the XANES analyses, it is revealed that the change of oxidation state is influenced by the presence of both electron and hole carriers in the two-carrier model of T’-structure.

Microprobe X-ray Absorption Spectroscopic Determination of the Oxidation State of Intracellular Chromium following Exposure of V79 Chinese Hamster Lung Cells to Genotoxic Chromium Complexes

1997 ◽  
Vol 10 (5) ◽  
pp. 533-535 ◽  
Author(s):  
Carolyn T. Dillon ◽  
Peter A. Lay ◽  
Marian Cholewa ◽  
George J. F. Legge ◽  
Antonio M. Bonin ◽  
...  
Keyword(s):  
Oxidation State ◽  
Chinese Hamster ◽  
Spectroscopic Determination ◽  
Lung Cells ◽  
Chromium Complexes ◽  
X Ray ◽  
X Ray Absorption

Direct determination of oxidation state of gold deposits in metal-reducing bacterium Shewanella algae using X-ray absorption near-edge structure spectroscopy (XANES)

2007 ◽  
Vol 103 (6) ◽  
pp. 568-571 ◽  
Author(s):  
Yasuhiro Konishi ◽  
Takeshi Tsukiyama ◽  
Norizoh Saitoh ◽  
Toshiyuki Nomura ◽  
Shinsuke Nagamine ◽  
...  
Keyword(s):  
Oxidation State ◽  
Direct Determination ◽  
Gold Deposits ◽  
Edge Structure ◽  
X Ray ◽  
Shewanella Algae ◽  
X Ray Absorption

X-ray absorption edge determination of the oxidation state and coordination number of copper. Application to the type 3 site in Rhus vernicifera laccase and its reaction with oxygen

1987 ◽  
Vol 109 (21) ◽  
pp. 6433-6442 ◽  
Author(s):  
Lung Shan Kau ◽  
Darlene J. Spira-Solomon ◽  
James E. Penner-Hahn ◽  
Keith O. Hodgson ◽  
Edward I. Solomon
Keyword(s):  
Coordination Number ◽  
Oxidation State ◽  
Absorption Edge ◽  
X Ray ◽  
Rhus Vernicifera ◽  
Type 3 ◽  
X Ray Absorption

scholarly journals A compact furnace for in situ X-ray absorption spectroscopy: design, fabrication and study of cationic oxidation states in Pr6O11 and NiO

2021 ◽  
Vol 28 (2) ◽  
pp. 455-460
Author(s):  
Suchinda Sattayaporn ◽  
Somboonsup Rodporn ◽  
Pinit Kidkhunthod ◽  
Narong Chanlek ◽  
Chutarat Yonchai ◽  
...  
Keyword(s):  
Oxidation State ◽  
Absorption Spectroscopy ◽  
Heating Temperature ◽  
Reduction Process ◽  
Oxidation States ◽  
Quartz Tube ◽  
Edge Structure ◽  
X Ray ◽  
X Ray Absorption

A well designed compact furnace has been designed for in situ X-ray absorption spectroscopy (XAS). It enables various heat ramps from 300 K to 1473 K. The furnace consists of heaters, a quartz tube, a circulated refrigerator and a power controller. It can generate ohmic heating via an induction process with tantalum filaments. The maximum heating rate exceeds 20 K min−1. A quartz tube with gas feedthroughs allows the mixing of gases and adjustment of the flow rate. The use of this compact furnace allows in situ XAS investigations to be carried out in transmission or fluorescence modes under controlled temperature and atmosphere. Moreover, the furnace is compact, light and well compatible to XAS. The furnace was used to study cationic oxidation states in Pr6O11 and NiO compounds under elevated temperature and reduced atmosphere using the in situ X-ray absorption near-edge structure (XANES) technique at beamline 5.2 SUT-NANOTEC-SLRI of the Synchrotron Light Research Institute, Thailand. At room temperature, Pr6O11 contains a mixture of Pr3+ and Pr4+ cations, resulting in an average oxidation state of +3.67. In situ XANES spectra of Pr (L 3-edge) show that the oxidation state of Pr4+ cations was totally reduced to +3.00 at 1273 K under H2 atmosphere. Considering NiO, Ni2+ species were present under ambient conditions. At 573 K, the reduction process of Ni2+ occurred. The Ni0/Ni2+ ratio increased linearly with respect to the heating temperature. Finally, the reduction process of Ni2+ was completely finished at 770 K.

EELS and Xanes Analysis of Plutonium and Cerium Edges From Titanate Ceramics for Fissile Materials Disposal

1999 ◽  
Vol 5 (S2) ◽  
pp. 768-769
Author(s):  
J.A. Fortner ◽  
E.C. Buck ◽  
A.J. Kropf ◽  
A.J. Bakel ◽  
M.C. Hash ◽  
...  
Keyword(s):  
Oxidation State ◽  
Electron Loss ◽  
Edge Structure ◽  
X Ray ◽  
Titanate Ceramics ◽  
X Ray Absorption ◽  
Photon Source ◽  
Titanate Ceramic ◽  
Exafs Spectra

We report x-ray absorption near edge structure (XANES) and extended x-ray fine structure analysis (EXAFS) spectra from the plutonium Llll and cerium Lm edges in prototype titanate ceramic hosts for disposal of surplus fissile materials. These spectra were obtained using the MRCAT beamline at the Advanced Photon Source (APS). The XANES and EXAFS results are compared with electron loss spectra (EELS) determination of oxidation state from the plutonium MlV,V and cerium MlV,V edges [1,2]. The titanate ceramics studied are based upon the hafniumpyrochlore and zirconolite mineral structures and will serve as an immobilization host, containing as much as 10 weight % fissile plutonium, and 20 weight % (natural or depleted) uranium. Similar formulations were composed using cerium as a “surrogate” element, replacing both plutonium and uranium in the ceramic matrix. We find the plutonium to be present almost entirely as Pu (IV), while the cerium is clearly in a mixed III-IV oxidation state in the surrogate ceramic.

In situ determination of the nickel oxidation state in La2NiO4+δ and La4Ni3O10−δ using X-ray absorption near-edge structure

2011 ◽  
Vol 21 (46) ◽  
pp. 18592 ◽  
Author(s):  
Russell J. Woolley ◽  
Benoit N. Illy ◽  
Mary P. Ryan ◽  
Stephen J. Skinner
Keyword(s):  
Oxidation State ◽  
Edge Structure ◽  
X Ray ◽  
Nickel Oxidation ◽  
X Ray Absorption
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