Mid-infrared ellipsometry, Raman and X-ray diffraction studies of Al Ga1−N/AlN/Si structures

Single crystal fibers of 30% Er3+-doped compound of Y3(ScxGa1−x)5O12 have been grown by using the micro-pulling down (μ-PD) technique successfully. Our main purpose is to tune the fluorescence properties by adjusting the ratios of Sc3+ and Ga3+ ions inside the matrix crystals. The crystal structures of the series compounds were measured and analyzed through X-ray diffraction (XRD) measurements. The components and doping elements distributions were measured by the X-ray Fluorescence spectrometry and electron-probe microanalyzer. The absorption and mid-infrared fluorescence spectra, including the fluorescent lifetime of Er3+:4I13/2 and 4I11/2 levels were measured and compared systematically at room temperature. Spectral analysis indicated that the fluorescent lifetime of Er3+:4I13/2 tended to shorten and the emission spectra began to show a red shift when the proportion of YSG increased in the compound. Furthermore, the Raman spectra were measured to reveal the variations of lattice vibration and phonon energy.

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AlGaN Solid Solution Grown on 3C-SiC(111)/Si(111) Pseudosubstrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.740-742.103 ◽

2013 ◽

Vol 740-742 ◽

pp. 103-106

Author(s):

Katja Tonisch ◽

Robert Benzig ◽

Gernot Ecke ◽

Jörg Pezoldt

Keyword(s):

Solid Solution ◽

Residual Stress ◽

Hydrostatic Pressure ◽

Lattice Distortion ◽

Biaxial Tension ◽

X Ray Diffraction ◽

Grown Layer ◽

X Ray ◽

Infrared Ellipsometry ◽

Layer Composition

The growth of AlGaN solid solutions on 3C-SiC(111)/Si(111) is demonstrated. The residual stress of the grown layer was investigated by high resolution X-ray diffraction (HRXRD) and infrared ellipsometry. Analysis of the HRXRD data showed that the observed lattice distortion was caused partially by hydrostatic pressure and partially by biaxial tension. The residual stress depends on the layer composition and weakly on the growth temperature.

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Incorporating Far-Infrared Data into Carbonate Mineral Analyses

Minerals ◽

10.3390/min10070628 ◽

2020 ◽

Vol 10 (7) ◽

pp. 628

Author(s):

Stephen Campbell ◽

Kristin M. Poduska

Keyword(s):

Far Infrared ◽

Carbonate Mineral ◽

X Ray Diffraction ◽

Mid Infrared ◽

X Ray ◽

Peak Overlap ◽

Spectral Changes ◽

Mineral Analyses ◽

Fir Spectra ◽

Infrared Data

Polycrystalline carbonate minerals (including calcite, Mg-calcite, and aragonite) can show distinctive variations in their far-infrared (FIR) spectra. We describe how to identify mixed-phase samples by correlating FIR spectral changes with mid-infrared spectra, X-ray diffraction data, and simple peak overlap simulations. Furthermore, we show how to distinguish portlandite-containing (Ca(OH) 2 ) mixtures that are common in heated calcium carbonate samples. Ultimately, these results could be used for tracking how minerals are formed and how they change during environmental exposure or processing after extraction.

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Thermo-Optical Properties of Nd0.3Sm0.7NiO3 Ceramic

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.55.7 ◽

2008 ◽

Vol 55 ◽

pp. 7-12

Author(s):

Cecile Napierala ◽

Mathieu Edely ◽

Patrick Laffez ◽

Laurent Sauques

Keyword(s):

Phase Transition ◽

Sol Gel ◽

Optical Measurements ◽

Infrared Range ◽

X Ray Diffraction ◽

Optical Contrast ◽

Metal Insulator ◽

Mid Infrared ◽

X Ray ◽

Insulator Phase Transition

Nd0.3Sm0.7NiO3 ceramic has been synthesised using a sol-gel method and annealing at oxygen pressure. Nd0.3Sm0.7NiO3 exhibits a reversible metal insulator phase transition which is, in the infrared range, responsible of a thermal-optical contrast. Samples are structurally characterized by X-ray diffraction and thermogravimetric analysis. The Nd0.3Sm0.7NiO3 thermal – optical contrast is characterized in the mid-infrared range, using reflectance and thermal-optical measurements.

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Correlation between luminescence properties and microstructure of hydrogenated amorphous carbon films investigated by X-ray diffraction and infrared ellipsometry

Solid State Communications ◽

10.1016/s0038-1098(99)00216-1 ◽

1999 ◽

Vol 111 (6) ◽

pp. 293-298 ◽

Cited By ~ 9

Author(s):

C. Godet ◽

T. Heitz ◽

J.E. Bourée ◽

B. Bouchet ◽

J. Dixmier ◽

...

Keyword(s):

Amorphous Carbon ◽

Carbon Films ◽

Luminescence Properties ◽

X Ray Diffraction ◽

Amorphous Carbon Films ◽

X Ray ◽

Hydrogenated Amorphous Carbon ◽

Infrared Ellipsometry ◽

Hydrogenated Amorphous

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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Ribosome Structural Organization

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051670 ◽

1974 ◽

Vol 32 ◽

pp. 332-333

Author(s):

James A. Lake

Keyword(s):

Ribosomal Proteins ◽

Structural Organization ◽

Three Dimensional ◽

Small Subunit ◽

Structural Studies ◽

X Ray Diffraction ◽

Specific Antibodies ◽

X Ray ◽

E Coli ◽

Complete Sequences

The understanding of ribosome structure has advanced considerably in the last several years. Biochemists have characterized the constituent proteins and rRNA's of ribosomes. Complete sequences have been determined for some ribosomal proteins and specific antibodies have been prepared against all E. coli small subunit proteins. In addition, a number of naturally occuring systems of three dimensional ribosome crystals which are suitable for structural studies have been observed in eukaryotes. Although the crystals are, in general, too small for X-ray diffraction, their size is ideal for electron microscopy.

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Electron Microscopy of Human Gallstones

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065523 ◽

1971 ◽

Vol 29 ◽

pp. 296-297

Author(s):

C. Wolpers ◽

R. Blaschke

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bile Pigment ◽

X Ray Diffraction ◽

Triclinic Crystal System ◽

X Ray ◽

Follow Up Study ◽

Infra Red ◽

Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

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High Resolution Replication of Organoclay Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055126 ◽

1982 ◽

Vol 40 ◽

pp. 576-577

Author(s):

W. W. Barker ◽

W. E. Rigsby ◽

V. J. Hurst ◽

W. J. Humphreys

Keyword(s):

Clay Mineral ◽

Organic Molecule ◽

Organic Molecules ◽

X Ray Diffraction ◽

Xrd Pattern ◽

X Ray ◽

Naturally Occurring ◽

Silicate Layers ◽

Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

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