X-ray Absorption Spectroscopic Evidence on the Partial Formation of Copper(III) in the Superconducting La2CuO4.08

1995 ◽  
Vol 117 (28) ◽  
pp. 7556-7557 ◽  
Author(s):  
Jin-Ho Choy ◽  
Dong-Kuk Kim ◽  
Sung-Ho Hwang ◽  
Jung-Chul Park
Keyword(s):  
Spectroscopic Evidence ◽  
X Ray ◽  
Partial Formation ◽  
X Ray Absorption

X-ray absorption spectroscopic evidence for a unique nickel site in Clostridium thermoaceticum carbon monoxide dehydrogenase

1987 ◽  
Vol 26 (15) ◽  
pp. 2477-2479 ◽  
Author(s):  
Stephen P. Cramer ◽  
Marly K. Eidsness ◽  
W. H. Pan ◽  
Thomas A. Morton ◽  
Steve W. Ragsdale ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Carbon Monoxide Dehydrogenase ◽  
Clostridium Thermoaceticum ◽  
Spectroscopic Evidence ◽  
X Ray ◽  
X Ray Absorption

scholarly journals X-ray-absorption-spectroscopic evidence for a novel iron cluster in hydrogenase II from Clostridium pasteurianum

1989 ◽  
Vol 259 (2) ◽  
pp. 597-600 ◽  
Author(s):  
G N George ◽  
R C Prince ◽  
K E Stokley ◽  
M W Adams ◽  
K E Stockley
Keyword(s):  
Structural Type ◽  
Spectroscopic Properties ◽  
The Other ◽  
Clostridium Pasteurianum ◽  
Iron Cluster ◽  
Spectroscopic Evidence ◽  
X Ray ◽  
Unknown Structure ◽  
X Ray Absorption

Hydrogenase II from Clostridium pasteurianum contains three different iron-sulphur clusters. Two are [4Fe-4S](2+.1+) clusters, whereas the other, which is thought to be the site of interaction with H2 and is known as the ‘H cluster’, is of unknown structure and possesses unusual spectroscopic properties. Analysis of the iron e.x.a.f.s. spectra shows that the H cluster contains iron co-ordinated mostly to sulphur and possesses 2.8 A (1 A = 0.1 nm) Fe--Fe separations when oxidized and 3.3 A Fe--Fe separations when reduced with H2. The data suggest that the reduced H cluster represents a new structural type of iron-sulphur cluster.

X-ray Absorption Spectroscopic Evidence for the Complexation of Hg(II) by Reduced Sulfur in Soil Humic Substances

1999 ◽  
Vol 33 (2) ◽  
pp. 257-261 ◽  
Author(s):  
K. Xia ◽  
U. L. Skyllberg ◽  
W. F. Bleam ◽  
P. R. Bloom ◽  
E. A. Nater ◽  
...  
Keyword(s):  
Humic Substances ◽  
Spectroscopic Evidence ◽  
X Ray ◽  
Reduced Sulfur ◽  
X Ray Absorption

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

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