scholarly journals Halide Electroadsorption on Single Crystal Surfaces

1996 ◽  
Vol 451 ◽  
Author(s):  
B. M. Ocko ◽  
Th. Wandlowski
Keyword(s):  
Lattice Gas ◽  
Ordered Structure ◽  
Lateral Interactions ◽  
Crystal Surfaces ◽  
Single Crystal Surfaces ◽  
Critical Potential ◽  
X Ray ◽  
X Ray Scattering ◽  
Disordered Phase ◽  
Ordered Phases

ABSTRACTThe structure and phase behavior of halides have been investigated on single crystals of Ag and Au using synchrotron x-ray scattering techniques. The adlayer coverages are potential dependent. For all halides studied we found that with increasing potential, at a critical potential, a disordered adlayer transforms into an ordered structure. Often these ordered phases are incommensurate and exhibit potential-dependent lateral separations (electrocom-pression). We have analyzed the electrocompression in terms of a model which includes lateral interactions and partial charge. A continuous compression is not observed for Br on Ag(100). Rather, we find that the adsorption is site-specific (lattice gas) in both the ordered and disordered phases. The coverage increases with increasing potential and at a critical potential the disordered phase transforms to a well-ordered commensurate structure.

Electrochemical and X-ray scattering study of well defined RuO2 single crystal surfaces

2002 ◽  
Vol 524-525 ◽  
pp. 201-218 ◽  
Author(s):  
T.E Lister ◽  
Y Chu ◽  
W Cullen ◽  
H You ◽  
R.M Yonco ◽  
...  
Keyword(s):  
Single Crystal ◽  
Crystal Surfaces ◽  
Single Crystal Surfaces ◽  
X Ray ◽  
X Ray Scattering ◽  
Scattering Study ◽  
Ray Scattering

Quantification of Starch Order in Physically Modified Rice Flours Using Small-Angle X-ray Scattering (SAXS) and Fourier Transform Infrared (FT-IR) Spectroscopy

2021 ◽  
pp. 000370282110282
Author(s):  
Daitaro Ishikawa ◽  
Jiamin Yang ◽  
Tomoyuki Fujii
Keyword(s):  
Infrared Spectroscopy ◽  
Small Angle ◽  
Water Sorption ◽  
Order Parameter ◽  
Rice Flour ◽  
Ordered Structure ◽  
X Ray ◽  
Glucose Unit ◽  
X Ray Scattering ◽  
Ray Scattering

The purpose of this study was to understand the ordered structure of starch in rice flour based on a physical modification with non-heating, milling, and water sorption through the structural evaluation of rice flour using small-angle X-ray scattering (SAXS) and infrared spectroscopy within the 4000–100 cm−1 region. The SAXS pattern of the samples with low moisture contents subjected to milling yield a band within the 0.4–0.9 nm−1 of the q range owing to a lamellar repeat of starch with an ordered structure in rice flour. We proposed an order parameter using the intensity of the SAXS band to quantify the order structure of starch in rice flour, and the true density was negatively correlated with the order parameter. Infrared band at 990 cm−1 in COH bending mode applied to the hydroxyl group of C6 shifted to a low wavenumber corresponding to the order parameter. A linear correlation was found between the order parameter and the 990 cm−1 and band at 861 cm−1 owing to COC symmetrical stretching of glycoside bond and CH2 deformation of the glucose unit of starch, 572, 472, and 436 cm−1, owing to the pyranose ring in the glucose unit of starch. The identified infrared bands are effective for quantifying the ordered structure of starch at the lamellar level. When subjected to water sorption, the band position at 990 cm−1 shifted to a higher wavenumber above a water activity of 0.7. This result revealed that the water-induced transition of glass to rubber of starch in rice flour can be clearly evaluated through infrared spectroscopy using the band at 990 cm−1. In addition, the band at 861 cm−1 also shifted to a higher wavenumber, whereas those at 572 and 436 cm−1 did not show a significant shift. These results indicate that water sorption slightly affects the internal structure and may mainly affect the surface of starch.

scholarly journals Strain mapping on gold thin film buckling and silicon blistering

2005 ◽  
Vol 875 ◽  
Author(s):  
P. Goudeau ◽  
N. Tamura ◽  
G. Parry ◽  
J. Colin ◽  
C. Coupeau ◽  
...  
Keyword(s):  
Thin Film ◽  
X Ray Diffraction ◽  
Crystal Surfaces ◽  
Strain Mapping ◽  
Strain Fields ◽  
Single Crystal Surfaces ◽  
X Ray ◽  
Gold Thin Film ◽  
Compressive Stresses ◽  
Strain Stress

AbstractStress/Strain fields associated with thin film buckling induced by compressive stresses or blistering due to the presence of gas bubbles underneath single crystal surfaces are difficult to measure owing to the microscale dimensions of these structures. In this work, we show that micro Scanning X-ray diffraction is a well suited technique for mapping the strain/stress tensor of these damaged structures.

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