Non-Destructive X-Ray Diffraction with 30-Micron Spatial Resolution: Some Examples

ABSTRACTWe have been measuring x-ray diffraction spectra of small samples of layers in cross-sections using a Micro X-ray diffractometer (PSPC/MDG) system since 1988. In measuring with xray diffractometry, the position sensitive proportional counter (PSPC) covers 150 degrees of x-ray diffraction, continuously. The data are accumulated by the multichannel analyser (MCA) and monitored on a CRT during the measurement period. Mounted samples can rotate around three axes. The XRD spectra are very like those from a wide angle goniometer used in powder diffraction. Normally the spatial limits are around 30 microns in diameter, as we have found experimentallly in our samples. We feel this system is very feasible for art and archaeological studies. Some case studies are presented.

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Mineral phases and element composition of the copper hyperaccumulator lichen Lecanora polytropa

Mineralogical Magazine ◽

10.1180/minmag.2008.072.2.607 ◽

2008 ◽

Vol 72 (2) ◽

pp. 607-616 ◽

Cited By ~ 12

Author(s):

O. W. Purvis ◽

B. Pawlik-Skowrońska ◽

G. Cressey ◽

G. C. Jones ◽

A. Kearsley ◽

...

Keyword(s):

Usnic Acid ◽

Sensitive Detector ◽

X Ray Diffraction ◽

Southern Sweden ◽

X Ray ◽

Mineral Phases ◽

Position Sensitive ◽

Metal Oxalate ◽

Crystalline Aggregates ◽

Non Destructive

AbstractMineral phases and element localization were investigated in the vivid turquoise-coloured lichen, Lecanora polytropa, sampled from a psammite boulder in a wall supporting mine spoil at the abandoned copper mine, Riddarhyttan Kopparverke, southern Sweden. Normally pale yellowish (usnic acid), the lichen is turquoise coloured internally with bluish inclusions. X-ray mapping shows that Cu occurs on and within the lichen and does not coincide with P or S, suggesting that it is indeed associated with carbon or other elements not detected (or reported) using X-ray mapping. Scanning electron microscopy in back-scatter mode confirmed that the greatest Cu concentrations occur in the form of crystalline aggregates in coloured inclusions below the major internal turquoise layer with smaller Cu contents. X-ray diffraction with a position-sensitive detector (XRD-PSD) confirmed coloured crystalline aggregates consisted of the copper oxalate, moolooite. The study confirms the value of XRD-PSD as a non-destructive tool to characterize small (~50 μm) metal oxalate inclusions obtained from within lichen samples.

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Miscibility Study of Chitosan and Methylcellulose Blends

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.802 ◽

2013 ◽

Vol 750-752 ◽

pp. 802-805 ◽

Cited By ~ 9

Author(s):

Peng Tao Liu ◽

Xiang Mei Wei ◽

Zhong Liu

Keyword(s):

Thermogravimetric Analysis ◽

Cross Sections ◽

Wide Angle ◽

X Ray Diffraction ◽

Scanning Electronic Microscopy ◽

Electronic Microscopy ◽

Sem Images ◽

X Ray ◽

Ft Ir

The miscibility of chitosan / methylcellulose (CH/MC) blends was studied by FT IR, wide-angle X-ray diffraction (WAXD), thermogravimetric analysis (TGA), and scanning electronic microscopy (SEM). The regular changes of FT IR and WAXD spectra of CH/MC blend powder indicated the miscibility of the blends. TGA curves and SEM images of cross-sections of the blends films showed partly miscibility.

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Measurement Of Retained Austenite in Stainless Steel Using Imaging Plate

Advances in X-ray Analysis ◽

10.1154/s0376030800016025 ◽

1993 ◽

Vol 37 ◽

pp. 483-490 ◽

Cited By ~ 2

Author(s):

Katsunari Sasaki ◽

Yukio Hirose ◽

Toshihiko Sasaki

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Corrosion Resistance ◽

Retained Austenite ◽

Lattice Strain ◽

Imaging Plate ◽

Wide Angle ◽

X Ray Diffraction ◽

X Ray ◽

Non Destructive

There are several methods for the measurement of retained austenite in steels, which influences mechanical behavior and corrosion resistance of steels. Among them, X-ray diffraction methods using a wide angle goniometer or X-ray stress analyzer are commonly used because the methods are non-destructive, giving useful information about residual stress or lattice strain as well.

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Highlights in the history of X-ray topography1

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1995.210.6.394 ◽

1995 ◽

Vol 210 (6) ◽

Author(s):

A. R. Lang

Keyword(s):

Magnetic Domain ◽

Diffraction Theory ◽

Dislocation Loops ◽

X Ray Diffraction ◽

X Ray ◽

Domain Structures ◽

Structure Factors ◽

History Of ◽

Dislocation Sources ◽

Non Destructive

AbstractX-ray topography provides a non-destructive method of mapping point-by-point variations in orientation and reflecting power within crystals. The discovery, made by several workers independently, that in nearly perfect crystals it was possible to detect individual dislocations by X-ray diffraction contrast started an epoch of rapid exploitation of X-ray topography as a new, general method for assessing crystal perfection. Another discovery, that of X-ray Pendellösung, led to important theoretical developments in X-ray diffraction theory and to a new and precise method for measuring structure factors on an absolute scale. Other highlights picked out for mention are studies of Frank-Read dislocation sources, the discovery of long dislocation helices and lines of coaxial dislocation loops in aluminium, of internal magnetic domain structures in Fe-3 wt.% Si, and of stacking faults in silicon and natural diamonds.

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Control of the phase composition of advanced calcium phosphates using an x-ray diffractometer with a curved position-sensitive detector

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-6-29-35 ◽

2020 ◽

Vol 86 (6) ◽

pp. 29-35

Author(s):

V. P. Sirotinkin ◽

O. V. Baranov ◽

A. Yu. Fedotov ◽

S. M. Barinov

Keyword(s):

Phase Composition ◽

Calcium Phosphates ◽

Position Sensitive Detector ◽

Sensitive Detector ◽

X Ray Diffraction ◽

X Ray ◽

Impurity Phases ◽

Position Sensitive ◽

Diffraction Peaks ◽

Diffraction Patterns

The results of studying the phase composition of advanced calcium phosphates Ca10(PO4)6(OH)2, β-Ca3(PO4)2, α-Ca3(PO4)2, CaHPO4 · 2H2O, Ca8(HPO4)2(PO4)4 · 5H2O using an x-ray diffractometer with a curved position-sensitive detector are presented. Optimal experimental conditions (angular positions of the x-ray tube and detector, size of the slits, exposure time) were determined with allowance for possible formation of the impurity phases during synthesis. The construction features of diffractometers with a position-sensitive detector affecting the profile characteristics of x-ray diffraction peaks are considered. The composition for calibration of the diffractometer (a mixture of sodium acetate and yttrium oxide) was determined. Theoretical x-ray diffraction patterns for corresponding calcium phosphates are constructed on the basis of the literature data. These x-ray diffraction patterns were used to determine the phase composition of the advanced calcium phosphates. The features of advanced calcium phosphates, which should be taken into account during the phase analysis, are indicated. The powder of high-temperature form of tricalcium phosphate strongly adsorbs water from the environment. A strong texture is observed on the x-ray diffraction spectra of dicalcium phosphate dihydrate. A rather specific x-ray diffraction pattern of octacalcium phosphate pentahydrate revealed the only one strong peak at small angles. In all cases, significant deviations are observed for the recorded angular positions and relative intensity of the diffraction peaks. The results of the study of experimentally obtained mixtures of calcium phosphate are presented. It is shown that the graphic comparison of experimental x-ray diffraction spectra and pre-recorded spectra of the reference calcium phosphates and possible impurity phases is the most effective method. In this case, there is no need for calibration. When using this method, the total time for analysis of one sample is no more than 10 min.

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