The Composition and Stability of Nicu Surface Alloys Grown by Ni(CO), Decomposition on Cu

1987 ◽  
Vol 111 ◽  
Author(s):  
Paul F.A. Alkemade ◽  
H. Fortuin ◽  
R. Balkenende ◽  
F. H. P. M. Habraken ◽  
W. F. Van Der Weg
Keyword(s):  
Grain Boundaries ◽  
Diffusion Coefficients ◽  
Diffusion Rate ◽  
Copper Substrate ◽  
Rutherford Backscattering ◽  
Sharp Interface ◽  
Rutherford Backscattering Spectroscopy ◽  
Surface Alloy ◽  
Surface Alloys ◽  
Nickel Carbonyl

AbstractThe composition of NiCu surface alloys, prepared by decomposition of nickel carbonyl on a Cu(100) surface, has been studied before as well as after annealing using MeV Rutherford Backscattering Spectroscopy.NiCu films with a thickness of 2 nm and of 10 nm, respectively, having a sharp interface with the copper substrate, were grown. The nickel fraction is found to be 65% and 93% respectively. The outermost monolayer is slightly enriched in copper. During annealing interdiffusion between the film and the interface occurs and the enrichment of the surface increases. In case of the 10 nm film the observed diffusion rate is much higher than is expected on the basis of diffusion coefficients published in the literature. This is ascribed to the presence of defects and/or grain boundaries in the grown surface alloy.

Effect of Macropore Structure on Desorption Diffusion Performance of N-Pentane on 5A Zeolite

2013 ◽  
Vol 634-638 ◽  
pp. 731-735 ◽  
Author(s):  
Lu Shi ◽  
Zong Jian Liu ◽  
Qun Cui ◽  
Hai Yan Wang ◽  
Hu Qing Yao
Keyword(s):  
Diffusion Coefficients ◽  
Diffusion Rate ◽  
Low Pressure ◽  
Fast Diffusion ◽  
Desorption Rate ◽  
Macropore Structure ◽  
5A Zeolite ◽  
Desorption Equilibrium

Desorption rate curves of n-pentane on 5A zeolites at 418 K and 10-0.03 kPa were determined, and the effects of different macropore structure on desorption performance were analyzed. Results show that macropore distribution of 5A-1 concentrates in 0.25-1.25 μm, while that of 5A-2 ranges from mesopore category to 0.3 μm, but 5A-3 contains both pores of 0.01-0.1 μm and 0.2-2 μm inside, reflecting a broadest distribution; 5A-3, 5A-1 and 5A-2 reach desorption equilibrium after 1100 s, 1400 s and 2000 s respectively at 0.03 kPa, indicating that abundant macropores make n-pentane fastest desorbed from 5A-3, but this advantage gradually disappears with the increasing pressure; the effective desorption diffusion coefficients of n-pentane on 5A-1, 5A-2 and 5A-3 are 4.2×10-15-2.2×10-14 m2/s, 2.0×10-15-2.3×10-14 m2/s, 7.4×10-15-2.4×10-14 m2/s respectively, suggesting that plenty macropores make the diffusivity less affected by the changes of pressure, which can guarantee a fast diffusion rate of n-pentane even at low pressure.

Surface analysis of a GaAs electron source using Rutherford backscattering spectroscopy

1994 ◽  
Vol 65 (3) ◽  
pp. 301-302 ◽  
Author(s):  
R. Calabrese ◽  
V. Guidi ◽  
P. Lenisa ◽  
B. Maciga ◽  
G. Ciullo ◽  
...  
Keyword(s):  
Surface Analysis ◽  
Electron Source ◽  
Rutherford Backscattering ◽  
Rutherford Backscattering Spectroscopy

Sorption Mechanism of Europium by Apatite Using Rutherford Backscattering Spectroscopy and Resonant Nuclear React ion Analysis

1997 ◽  
Vol 34 (1) ◽  
pp. 58-62 ◽  
Author(s):  
Toshihiko OHNUKI ◽  
Naofumi KOZAI ◽  
Hiroshi ISOBE ◽  
Takashi MURAKAMI ◽  
Shunya YAMAMOTO ◽  
...  
Keyword(s):  
Rutherford Backscattering ◽  
Rutherford Backscattering Spectroscopy ◽  
Sorption Mechanism ◽  
Ion Analysis
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