Clinopyroxenes from the Upper Layered Series Kap Edvard Holm, East Greenland

1971 ◽  
Vol 38 (293) ◽  
pp. 49-57 ◽  
Author(s):  
R. Elsdon
Keyword(s):  
Optical Properties ◽  
Single Crystals ◽  
Olivine Basalt ◽  
Parent Magma ◽  
Chemical Compositions ◽  
Measurable Effect ◽  
Layered Series ◽  
East Greenland ◽  
X Ray ◽  
Alkali Olivine Basalt

SummaryChemical compositions, unit-cell contents, and optical properties of six clinopyroxenes from the Upper Layered Series are presented. There is a gradual enrichment in iron upwards in the intrusion although there is no measurable effect on the optical properties, possibly because of Cr variation and exsolution of Fe and Ti as oxides. The chemistry of the clinopyroxenes is consistent with crystallization from a water-rich magma of transitional nature between tholeiite and alkali-olivine basalt. X-ray oscillation photographs of single crystals reveal the presence of sub-microscopic exsolution lamellae of pigeonite, a feature consistent with the transitional nature of the parent magma. Exsolution lamellae of titanomagnetite are ubiquitous and were formed at subsolidus temperatures in response to high buffered oxygen fugacity. Comparisons are made between the properties of clinopyroxenes from the Lower, Middle, and Upper Layered Series, and the conditions of crystallization of each series.

Optical Properties of Bi2Ge3O9 Single Crystals X-Ray Irradiation Effects

1989 ◽  
Vol 114 (1) ◽  
pp. 397-405 ◽  
Author(s):  
C. Zaldo ◽  
L. Contreras ◽  
L. Arizmendi ◽  
E. Dieguez
Keyword(s):  
Optical Properties ◽  
Single Crystals ◽  
Irradiation Effects ◽  
X Ray

Characterization and Optical Properties of Zinc Oxide Films Prepared by Microwave Technique

2015 ◽  
Vol 804 ◽  
pp. 7-11
Author(s):  
Suparut Narksitipan ◽  
Thaweedet Awirut
Keyword(s):  
Zinc Oxide ◽  
Optical Properties ◽  
Surface Film ◽  
Optical Transmittance ◽  
Hexagonal Structure ◽  
Zno Films ◽  
Chemical Compositions ◽  
X Ray ◽  
Microwave Technique ◽  
Vis Spectroscopy

In this research, zinc oxide (ZnO) films were prepared using a wet chemical reaction via a microwave technique. X-ray diffraction techniques (XRD) and energy dispersive x-ray spectroscopy (EDS) were used to study the phases, crystalline structures, chemical compositions and optical properties of the films, respectively. Optical transmittance was also measured through UV-VIS spectroscopy. Surface film morphologies were investigated by scanning electron microscopy (SEM). As a result, a ZnO phase with a hexagonal structure was detected. The EDS spectrum shows that elements of Zn and O were present. The average optical transmittance value for all films was 75% at a wavelength of 370-375 nm, a comparison among the films obtained at different times show a transmittance value slightly higher for films obtained at higher times. A calculation of the energy band gap of ZnO films was estimated to be in the range of 3.31 to 3.35 eV. Additional, the ZnO films showed a smooth surface.

scholarly journals The growth of Mg2TiO4 single crystals using a four-mirror furnace

2011 ◽  
Vol 76 (11) ◽  
pp. 1561-1566 ◽  
Author(s):  
Aleksandar Golubovic ◽  
Marko Radovic
Keyword(s):  
Optical Properties ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
Single Crystals ◽  
Powder Diffraction ◽  
Spectroscopic Ellipsometry ◽  
Lattice Parameter ◽  
Published Data ◽  
X Ray ◽  
Float Zone

A single crystal of Mg2TiO4 was grown by the travelling solvent float zone (TSFZ) method. The lattice parameter a = 0.8444(8) nm was determined by X-ray powder diffraction analysis. The optical properties of the Mg2TiO4 single crystals were studied using spectroscopic ellipsometry. The obtained results are discussed and compared with published data.

Clinopyroxenes of the gabbro cumulates of the Kap Edvard Holm complex, east Greenland

1965 ◽  
Vol 34 (268) ◽  
pp. 177-193 ◽  
Author(s):  
W. A. Deer ◽  
D. Abbott
Keyword(s):  
Optical Properties ◽  
Chemical Composition ◽  
Large Volume ◽  
Major Part ◽  
Progressive Change ◽  
Layered Series ◽  
East Greenland ◽  
Cell Parameters ◽  
Lower Temperature ◽  
Primary Minerals

SummaryThe major part of the Kap Edvard Holm complex consists of two series of conspicuously banded gabbroic rocks. The primary minerals of both lower and upper layered series show a progressive change in composition, from higher to lower temperature phases, with increasing height in the complex. Minor fluctuations in the differentiation of the two series occur but the division of the layered rocks into the lower and upper series is based on abrupt and major changes in the compositions of the pyroxenes, olivine and plagioclase. This break is correlated with the injection of a large volume of undifferentiated magma which occurred after much of the lower layered series had consolidated, and from which the rocks of the upper layered series were formed. Twelve pyroxenes, five from the lower and seven from the upper layered series have been analysed; the relationships between their optical properties and chemical composition, and between the cell parameters and composition are considered. The crystallization trend of the pyroxenes is compared with that of the Skaergaard calcium-rich pyroxenes; it is suggested that the restricted enrichment in iron shown by the Kap Edvard Holm pyroxenes may be related to the higher water-vapour pressures which prevailed during much of the period of crystallization.

Petrology of alkaline lamprophyres from the Coldwell alkaline complex, northwestern Ontario

1991 ◽  
Vol 28 (10) ◽  
pp. 1653-1663 ◽  
Author(s):  
Roger H. Mitchell ◽  
R. Garth Platt ◽  
Maureen Downey ◽  
David G. Laderoute
Keyword(s):  
Trace Elements ◽  
Single Crystals ◽  
Magma Chamber ◽  
Rare Earths ◽  
Olivine Basalt ◽  
Alkaline Complex ◽  
Northwestern Ontario ◽  
Alkali Olivine Basalt ◽  
Incompatible Trace Elements ◽  
Alkaline Lamprophyres

A suite of alkaline lamprophyre dikes emplaced in centers I and II rocks of the Coldwell alkaline complex is composed of camptonites with calcite ocelli, camptonites with quartz macrocrysts, amphibole camptonites, monchiquites, and sannaites. The camptonites are characterized by phenocrysts of olivine, aluminian pyroxene, kaersutite, and titanian ferropargasite set in a matrix of magnesian hastingsite, augite, plagioclase, biotite, magnetite, sphene, and minor nepheline. Quartz macrocrysts occur as corroded euhedral single crystals. Monchiquites are petrographically similar to the camptonites but are characterized by the presence of an isotropic groundmass. Sannaites contain aluminian and chromian diopside phenocrysts set in a matrix of ferroan pargasite, aluminian diopside, biotite, albitized plagioclase, and epidotized alkali feldspar.Major-element compositions indicate the ocellar camptonites, amphibole camptonites, and monchiquites have affinities with alkali olivine basalt and that monchiquites and camptonites are heteromorphs. None of the dikes represent primitive liquids. Poor correlations between incompatible trace elements (Sr, Ba, Nb, Zr, rare earths), together with the presence of reversely zoned and corroded phenocrysts, suggest that none of the lamprophyres represent single batches of magma. The lamprophyres are considered to be hybrid magmas, formed by the mixing of fragmented cumulates, several generations of phenocrysts, and batches of magma extracted from a continuously replenished evolving magma chamber located within the infrastructure of the complex. Quartz-bearing camptonites are considered to form by contamination of camptonites, although the source of the quartz cannot be determined.

Structural and Optical Properties of Group III-Nitride Quantum Wells Studied by (S)Tem and CL

1997 ◽  
Vol 482 ◽  
Author(s):  
H. Lakner ◽  
Q. Liu ◽  
G. Brockt ◽  
A. Radefeld ◽  
F. Schulze-Kraasch ◽  
...  
Keyword(s):  
Optical Properties ◽  
High Resolution ◽  
Quantum Wells ◽  
Structural Defects ◽  
Chemical Compositions ◽  
Contrast Imaging ◽  
X Ray ◽  
Group Iii ◽  
Scanning Transmission ◽  
Convergent Beam

AbstractWurtzite InGaN/GaN and AlGaN/GaN heterostructures grown on sapphire by metal organic vapor phase epitaxy were studied using scanning transmission electron microscopy (STEM), cathodoluminescence (CL) combined with secondary electron (SE) imaging, high resolution x-ray diffractometry (HRXRD), and atomic force microscopy (AFM).SE imaging and AFM were used to study the surface morphology. The results indicate the presence of the following structural defects on the surface of InGaN/GaN heterostructures: hexagonal mesa-like structures, hexagonal pyramids and micropipes, while the surface of the AlGaN/GaN heterostructures are mirror-like smooth. The local optical properties of defects and defect free regions were studied using spatially resolved CL at low temperature. In addition, the dependence of the optical properties of both sorts of heterostructures on the quantum well width or chemical composition of ternary materials was investigated. The structural properties of the heterostructures were studied by STEM and HRXRD. Convergent beam electron diffraction (CBED) and corresponding simulations, convergent beam imaging (CBIM), and high resolution x-ray diffraction (HRXRD) were used to study the strained layers. Dislocations and interface properties were characterized using bright-field imaging, while the chemical compositions fluctuations were analyzed by Z-contrast imaging and energy dispersive x-ray microanalysis (EDX).

scholarly journals Enhancement in crystalline perfection and optical properties of benzophenone single crystals: the remarkable effect of a liquid crystal

2011 ◽  
Vol 44 (4) ◽  
pp. 839-845 ◽  
Author(s):  
S. K. Kushwaha ◽  
N. Vijayan ◽  
K. K. Maurya ◽  
A. Kumar ◽  
B. Kumar ◽  
...  
Keyword(s):  
Optical Properties ◽  
Liquid Crystal ◽  
Single Crystals ◽  
Crystalline Perfection ◽  
X Ray ◽  
Remarkable Effect ◽  
Bulk Single Crystals ◽  
Transparent Region ◽  
First Time

The remarkable enhancement of the crystalline perfection of benzophenone (BP) crystals induced by liquid crystal (LC) doping has been investigated, and has in turn led to better optical properties. High-resolution X-ray diffractometry demonstrates that the structural grain boundaries present in pure crystals can be eliminated when the crystal is grown with LC doping. Thus, the high alignment capability of LCs has for the first time been utilized to enhance the quality of BP bulk single crystals. The LC-doped crystal exhibits higher optical transparency over its entire transparent region. The optical polarizing behaviour of the doped BP crystal is also improved.

Effect of crucible design on crystalline perfection and the enhanced optical properties of benzimidazole single crystals grown by the vertical Bridgman technique

2013 ◽  
Vol 46 (1) ◽  
pp. 276-278 ◽  
Author(s):  
B. Riscob ◽  
N. Vijayan ◽  
Mohd Shakir ◽  
M. A. Wahab ◽  
G. Bhagavannarayana
Keyword(s):  
Optical Properties ◽  
Melting Point ◽  
High Resolution ◽  
Single Crystals ◽  
X Ray Diffraction ◽  
Crystalline Perfection ◽  
Bridgman Technique ◽  
X Ray ◽  
Vertical Bridgman ◽  
Double Wall

Good quality benzimidazole (BMZ) single crystals were successfully grown by the vertical Bridgman technique (VBT). The unavoidable thermal-induced structural grain boundaries formed in the normal VBT growth of these crystals with low melting point were controlled by using a double-wall ampoule. The grown single crystals were subjected to high-resolution X-ray diffraction to assess their crystallinity. The enhancement of optical properties due to the improvement in crystalline perfection is also reported.

scholarly journals The optical properties of LiNbO3 single crystals obtained in air atmosphere

1999 ◽  
Vol 64 (10) ◽  
pp. 637-646 ◽  
Author(s):  
Aleksandar Golubovic ◽  
Slobodanka Nikolic ◽  
Rados Gajic ◽  
Stevan Djuric ◽  
Aleksandar Jelisijevic ◽  
...  
Keyword(s):  
Optical Properties ◽  
Single Crystals ◽  
Optical Constants ◽  
High Temperature Superconductor ◽  
Critical Diameter ◽  
Published Data ◽  
Critical Rate ◽  
X Ray ◽  
Air Atmosphere ◽  
Reflectance Data

Single crystals of LiNbO3 were grown by the Czochralski technique in an air atmosphere. The critical diameter and the critical rate of rotation were calculated. X-Ray measurements of the powder were carried out to obtain the lattice parameters.The optical constants were calculated by Kramers-Kronig analysis of reflectance data. The optical properties of LiNbO3 single crystals were studied for samples grown in an air atmosphere to investigate the influence of air on the optical properties of the formed crystals. A peak due to OH. gtroups appears in the transmission spectrum at 3385 cm -1. It was still present after annealing in an air atmosphere at temperature up to 873 K, but it was no longer detectable after annealing at 1473 K in an electric field. Thick films of the high-temperature superconductor YBa2Cu3O7 (Ag) were obtained on plates of LiNbO3 single crystals. The obtained results are discussed and compared with published data.

scholarly journals Single crystals of bismuth silicon oxide grown by the czochralski technique and their characterisation

1999 ◽  
Vol 64 (9) ◽  
pp. 553-561 ◽  
Author(s):  
Aleksandar Golubovic ◽  
Slobodanka Nikolic ◽  
Rados Gajic ◽  
Stevan Djuric ◽  
Andreja Valcic
Keyword(s):  
Optical Properties ◽  
Single Crystals ◽  
Silicon Oxide ◽  
Critical Diameter ◽  
Lattice Parameters ◽  
Published Data ◽  
Czochralski Technique ◽  
Critical Rate ◽  
Bismuth Silicon Oxide ◽  
X Ray

Single crystals of Bi12SiO20 were grown by the Czochralski technique. The critical diameter and the critical rate of rotation were calculated. Suitable polishing and etching solutions were determined. X-Ray measurements were performed on powdered samples to obtain the lattice parameters. The optical properties of the bismuth silicon oxide single crystals were investigated. The obtained results are discussed and compared with published data.

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