The quantitative determination of minerals in some metamorphosed volcanic rocks by X-ray powder diffraction

1968 ◽  
Vol 5 (2) ◽  
pp. 235-242 ◽  
Author(s):  
Calvert C. Bristol

A method is described for the quantitative X-ray powder diffraction determination of minerals in metamorphosed volcanic rocks of the greenschist, epidote-amphibolite, and amphibolite facies. In this method the intensity of the (111) diffraction for a powdered metallic Cu internal standard was compared to the intensities of selected diffractions for minerals of each facies.Graphs relating X-ray diffraction intensities to concentrations were prepared for actinolite, albite, almandine, anthophyllite, biotite, chlorite (omega: 1.59), diopside, epidote, hornblende, muscovite (2M1), plagioclase (An30), and quartz.Results using this method are within [Formula: see text] of those obtained by Rosiwal analysis.

1972 ◽  
Vol 9 (1) ◽  
pp. 36-42 ◽  
Author(s):  
Calvert C. Bristol

X-ray powder diffraction methods, successful in quantitative determination of silicate minerals in fine-grained rocks, have been applied to the determination of calcite, dolomite, and magnesite in greenschist facies meta-volcanic rocks. Internal standard graphs employing two standards (NaCl and Mo) have been determined.Carbonate mineral modes (calcite and dolomite) for 6 greenschist facies meta-volcanic rocks obtained by the X-ray powder method have been compared to normative carbonate mineral contents calculated for the same rocks. This comparison showed a maximum variation of 7.7 wt.% between the X-ray modes and the normative carbonate mineral contents of the rocks. Maximum standard deviation for the X-ray modes of these rocks was equivalent to 4.4 wt.%.


1957 ◽  
Vol 1 ◽  
pp. 59-72
Author(s):  
G. M. Faulring ◽  
R. D. Carpenter

AbstractThe amount of kyanite in samples obtained from magnetic and density separations of a kyanite ore was established by a quantitative X-ray diffraction procedure employing an internal standard. The accuracy of the results at low kyanite levels was improved by adding pure kyanite to the samples, analyzing these mixtures and extrapolating back to the lower level. The results were verified by X-ray diffraction analyses of synthetic mixtures containing amounts of kyanite approximately equal to that indicated in the ore samples. The percentage of error is estimated to be ±3per cent of the amount present in the range of 20 to 80 per cent kyanite.


2014 ◽  
Vol 70 (a1) ◽  
pp. C1560-C1560
Author(s):  
Fumiko Kimura ◽  
Wataru Oshima ◽  
Hiroko Matsumoto ◽  
Hidehiro Uekusa ◽  
Kazuaki Aburaya ◽  
...  

In pharmaceutical sciences, the crystal structure is of primary importance because it influences drug efficacy. Due to difficulties of growing a large single crystal suitable for the single crystal X-ray diffraction analysis, powder diffraction method is widely used. In powder method, two-dimensional diffraction information is projected onto one dimension, which impairs the accuracy of the resulting crystal structure. To overcome this problem, we recently proposed a novel method of fabricating a magnetically oriented microcrystal array (MOMA), a composite in which microcrystals are aligned three-dimensionally in a polymer matrix. The X-ray diffraction of the MOMA is equivalent to that of the corresponding large single crystal, enabling the determination of the crystal lattice parameters and crystal structure of the embedded microcrytals.[1-3] Because we make use of the diamagnetic anisotropy of crystal, those crystals that exhibit small magnetic anisotropy do not take sufficient three-dimensional alignment. However, even for these crystals that only align uniaxially, the determination of the crystal lattice parameters can be easily made compared with the determination by powder diffraction pattern. Once these parameters are determined, crystal structure can be determined by X-ray powder diffraction method. In this paper, we demonstrate possibility of the MOMA method to assist the structure analysis through X-ray powder and single crystal diffraction methods. We applied the MOMA method to various microcrystalline powders including L-alanine, 1,3,5-triphenyl benzene, and cellobiose. The obtained MOMAs exhibited well-resolved diffraction spots, and we succeeded in determination of the crystal lattice parameters and crystal structure analysis.


1993 ◽  
Vol 26 (4A) ◽  
pp. A181-A187 ◽  
Author(s):  
B F Usher ◽  
G W Smith ◽  
S J Barnett ◽  
A M Keir ◽  
A D Pitt

1988 ◽  
Vol 142 ◽  
Author(s):  
John F. Porter ◽  
Dan O. Morehouse ◽  
Mike Brauss ◽  
Robert R. Hosbons ◽  
John H. Root ◽  
...  

AbstractStudies have been ongoing at Defence Research Establishment Atlantic on the evaluation of non-destructive techniques for residual stress determination in structures. These techniques have included neutron diffraction, x-ray diffraction and blind-hole drilling. In conjunction with these studies, the applicability of these procedures to aid in metallurgical and failure analysis investigations has been explored. The x-ray diffraction technique was applied to investigate the failure mechanism in several bent turbo blower rotor shafts. All examinations had to be non-destructive in nature as the shafts were considered repairable. It was determined that residual stress profiles existed in the distorted shafts which strongly indicated the presence of martensitic microstuctures. These microstructures are considered unacceptable for these shafts due to the potential for cracking or in-service residual stress relaxation which could lead to future shaft distortion.


1992 ◽  
Vol 60 (24) ◽  
pp. 2986-2988 ◽  
Author(s):  
Y. H. Phang ◽  
D. E. Savage ◽  
T. F. Kuech ◽  
M. G. Lagally ◽  
J. S. Park ◽  
...  

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