scholarly journals APLIKACE TEXTURNÍ RTG-DIFRAKČNÍ ANALÝZY V TEKTONICE – KVANTIFIKACE PŘEDNOSTNÍ ORIENTACE KALCITU V KARBONÁTOVÝCH HORNINÁCH

2016 ◽  
Vol 23 (1-2) ◽  
Author(s):  
Stanislav Kurdík ◽  
Rostislav Melichar ◽  
Jiří Novák ◽  
Dalibor Všianský
Keyword(s):  
Diffraction Analysis ◽  
Deformation Mechanisms ◽  
Optical Methods ◽  
Tectonic Movement ◽  
X Ray Diffraction ◽  
Beam Direction ◽  
X Ray ◽  
Fine Grained ◽  
Pole Figures ◽  
Reflection Geometry

The goal of this work was to apply texture x-ray diffraction analysis to study naturally strained rocks, in which the quantification of main preferred orientation cannot be conducted by the optical methods. This method has mainly been developed for metallography and its application in geology has been very limited so far. Samples of the fine-grained limestone have been collected from an outcrop, in which the direction of tectonic movement has been known. Thus, the tectonic situation could be correlated with the data obtained by XRD texture analysis. Analyses have been done by two devices with different geometry of experiment. The first experiment (Schulz reflection geometry) needed correction for the gain data, because of tilting of the sample, which led to the misalignment of the sample from the x-ray beam direction. The second one (in-plane geometry) has been measured, when the sample has been fixed and rotated, thus the correction was not needed. The results in a form of pole figures reflect the mechanism of deformation. The orientation of cleavage planes of calcite parallel to foliation indicates a cataclastic flow. Thus, the method could be used to study deformation mechanisms. The asymmetry of the results can show sense of shear, but it could also reflect inhomogenities of the samples. 

scholarly journals Structural analysis of inclusions detected by x-ray inspection of preforms and parts from fine-grained graphite MPG-7

2019 ◽  
pp. 54-59
Author(s):  
A. V. Vershinin ◽  
E. G. Belyakova ◽  
M. V. Vershinina ◽  
E. V. Polyakov ◽  
V. G. Bamburov ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Structural Analysis ◽  
Diffraction Analysis ◽  
Structural Defects ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fine Grained

By X-ray diffraction analysis and Raman spectroscopy, we studied samples of fine-grained graphite MPG-7 with detected chemical and structural defects. We determined the effect of structural and chemical defects on the micro- and macrostructure of graphite and estimated its crystallinity depending on the type of defects detected.

Combined Thermal and X-Ray Diffraction Technique for Identification of Ceramicware Temper and Paste Minerals

1974 ◽  
Vol 39 (3) ◽  
pp. 477-483 ◽  
Author(s):  
Wayne C. Isphording
Keyword(s):  
High Temperature ◽  
Diffraction Analysis ◽  
Clay Minerals ◽  
Fine Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fine Grained ◽  
High Temperature Furnace ◽  
A New Technique ◽  
Temperature Furnace

AbstractThe identification of the original paste and temper minerals present in ceramicware fragments can often be useful in determining if the fragments are indigenous to the area or whether they represent tradeware. To date, it has generally been believed that no certain means existed to identify the mineral constitutents once they were destroyed in the original kiln-firing operation. A new technique is described that permits the investigator to often identify both temper and the fine-grained paste materials as well. This method involves: (1) crushing the fragment to a fine powder; (2) heating the powder in a high temperature furnace to sufficient temperatures to cause the constituent ions present to recombine to form new, high temperature minerals; and (3) X-ray diffraction analysis to identify the new minerals. In many cases, identification of the resulting high temperature minerals will clearly indicate the composition of the original clay paste and temper. Examples are shown for the clay minerals kaolinite, montmorillonite and palygorskite. Diffractograms are also presented for comparison of ceramic fragments from Mexico and Alabama that contain the above minerals as original constituents.

Ten-Vertex Polyhedral Monocarbaborane Chemistry. The Novel High-Yield Formation of the Ten-Vertex closo Compound [6-(PMe2Ph)-closo-1-CB9H9] from the Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11]

1993 ◽  
Vol 58 (12) ◽  
pp. 2924-2935 ◽  
Author(s):  
Jane H. Jones ◽  
Bohumil Štíbr ◽  
John D. Kennedy ◽  
Mark Thornton-Pett
Keyword(s):  
Nmr Spectroscopy ◽  
Diffraction Analysis ◽  
High Yield ◽  
Monoclinic Space Group ◽  
The Novel ◽  
X Ray Diffraction ◽  
Metal Centre ◽  
X Ray ◽  
Yield Formation ◽  
Boiling Toluene

Thermolysis of [8,8-(PMe2Ph)2-nido-8,7-PtCB9H11] in boiling toluene solution results in an elimination of the platinum centre and cluster closure to give the ten-vertex closo species [6-(PMe2Ph)-closo-1-CB9H9] in 85% yield as a colourles air stable solid. The product is characterized by NMR spectroscopy and single-crystal X-ray diffraction analysis. Crystals (from hexane-dichloromethane) are monoclinic, space group P21/c, with a = 903.20(9), b = 1 481.86(11), c = 2 320.0(2) pm, β = 97.860(7)° and Z = 8, and the structure has been refined to R(Rw) = 0.045(0.051) for 3 281 observed reflections with Fo > 2.0σ(Fo). The clean high-yield elimination of a metal centre from a polyhedral metallaborane or metallaheteroborane species is very rare.

Bis(μ-carboxylato)dienerhodium(I) Complexes - Synthesis, Characterization and Catalytic Activity

2008 ◽  
Vol 73 (8-9) ◽  
pp. 1205-1221 ◽  
Author(s):  
Jiří Zedník ◽  
Jan Sedláček ◽  
Jan Svoboda ◽  
Jiří Vohlídal ◽  
Dmitrij Bondarev ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Diffraction Analysis ◽  
Spectroscopic Methods ◽  
X Ray Diffraction ◽  
X Ray

Dinuclear rhodium(I) η2:η2-cycloocta-1,5-diene (series a) and η2:η2-norborna-2,5-diene (series b) complexes with μ-RCOO- ligands, where R is linear C21H43 (complexes 1a, 1b), CH2CMe3 (2a, 2b), 1-adamantyl (3a, 3b) and benzyl (4a, 4b), have been prepared and characterized by spectroscopic methods. Structures of complexes 2b, 3a and 4a were determined by X-ray diffraction analysis. Complexes prepared show low to moderate catalytic activity in polymerization of phenylacetylene in THF giving high-cis-transoid polymers, but they show only oligomerization activity in dichloromethane.

scholarly journals Crystals of the trp repressor-operator complex suitable for X-ray diffraction analysis.

1987 ◽  
Vol 262 (10) ◽  
pp. 4917-4921 ◽  
Author(s):  
A. Joachimiak ◽  
R.Q. Marmorstein ◽  
R.W. Schevitz ◽  
W. Mandecki ◽  
J.L. Fox ◽  
...  
Keyword(s):  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
Trp Repressor ◽  
X Ray
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