scholarly journals Short-range structure, the role of bismuth and property-structure correlations in bismuth borate glasses

2021 ◽  
Author(s):  
Christos P.E. Varsamis ◽  
Nikos Makris ◽  
Christina Valvi ◽  
E. I. Kamitsos
Keyword(s):  
Short Range ◽  
Composition Range ◽  
Reflectance Spectra ◽  
Borate Glasses ◽  
Infrared Reflectance ◽  
Bismuth Borate ◽  
Splat Quenching ◽  
Structure Correlations ◽  
Short Range Structure

Bismuth-containing borate glasses, xBi2O3-(1-x)B2O3, were synthesized in the broad composition range 0.20≤x≤0.80 by melting in Pt crucibles and splat-quenching between two metal blocks. Infrared reflectance spectra, measured in the range...

Structural and Optical Properties of Ho3+ Doped ZnO-Bi2O3-B2O3 Glasses

2014 ◽  
Vol 979 ◽  
pp. 98-101 ◽  
Author(s):  
Parnuwat Chimalawong ◽  
Keerati Kirdsiri ◽  
Jakrapong Kaewkhao ◽  
Pichet Limsuwan
Keyword(s):  
Molar Volume ◽  
Ground State ◽  
Borate Glass ◽  
Borate Glasses ◽  
Structural And Optical Properties ◽  
Melt Quenching ◽  
Bismuth Borate ◽  
Doped Zno ◽  
Bismuth Borate Glass

Ho3+ doped zinc bismuth borate glasses of the composition 10ZnO : 30Bi2O3 : (60-x)B2O3 : xHo2O3 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0 mol%) were fabricated by conventional melt quenching technique. In order to understand the role of Ho2O3 in these glasses, the density, molar volume and optical spectra were investigated. The molar volume decreases with an increase in Ho2O3 content, which is attributed to the structure becomes more compacted. The absorption spectra of Ho3+ doped in zinc bismuth borate glass correspond to several bands, which are assigned from the ground state, 5I8 to 5G5 (420 nm), 5G6 + 5F1 (451 nm), 5F2 + 5F4 (538 nm), 5F5 (643 nm) and 5I5 (1152 nm). Moreover, the optical basicities were also theoretically determined.

On the dual role of halogen in magnesium oxyhalide bismuth borate glasses: Insight through optical absorption

Optik ◽  
2017 ◽  
Vol 144 ◽  
pp. 22-25 ◽  
Author(s):  
Manjeet S. Dahiya ◽  
Arti Yadav ◽  
Satish Khasa
Keyword(s):  
Optical Absorption ◽  
Dual Role ◽  
Borate Glasses ◽  
Bismuth Borate

Infrared reflectance spectra of lithium borate glasses

1990 ◽  
Vol 126 (1-2) ◽  
pp. 52-67 ◽  
Author(s):  
E.I. Kamitsos ◽  
A.P. Patsis ◽  
M.A. Karakassides ◽  
G.D. Chryssikos
Keyword(s):  
Reflectance Spectra ◽  
Borate Glasses ◽  
Lithium Borate ◽  
Infrared Reflectance

Physical and Optical Properties of Ce3+ Doped in Bismuth Borate Glass

2013 ◽  
Vol 770 ◽  
pp. 254-257 ◽  
Author(s):  
Kitipun Boonin ◽  
Onanong Chamlek ◽  
Pruittipol Limkitjaroenporn ◽  
Hong Joo Kim ◽  
Jakrapong Kaewkhao
Keyword(s):  
Optical Properties ◽  
Absorption Spectra ◽  
Borate Glass ◽  
Optical Band Gap ◽  
Composition Range ◽  
Borate Glasses ◽  
Melt Quenching ◽  
Bismuth Borate ◽  
Bismuth Borate Glass ◽  
No Absorption

Bismuth borate glasses doped with cerium in the composition 50Bi2O3:(50-x)B2O3:xCeF3 were prepared for the composition range 0x2.5 (in mol%). The glass samples have been fabricated by the conventional melt quenching technique. The physical and optical properties of glass samples were investigated. The optical absorption spectra of the glasses have been measured in the wavelength range 190-1100 nm and no absorption peak was obtained in this region. The absorption spectra of all samples were shifted to longer wavelength with increasing of CeF3 concentrations. Optical band gap decreased and refractive index increased with increasing of CeF3 concentrations.

scholarly journals Mineral Physicochemistry Underlying Feature-Based Extraction of Mineral Abundance and Composition from Shortwave, Mid and Thermal Infrared Reflectance Spectra

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 347
Author(s):  
Carsten Laukamp ◽  
Andrew Rodger ◽  
Monica LeGras ◽  
Heta Lampinen ◽  
Ian C. Lau ◽  
...  
Keyword(s):  
Mineral Exploration ◽  
Relevant Information ◽  
Ore Deposits ◽  
Reflectance Spectra ◽  
Full Potential ◽  
Infrared Reflectance ◽  
Vibrational Modes ◽  
Diagnostic Features ◽  
Wide Range ◽  
Mineral Assemblages

Reflectance spectroscopy allows cost-effective and rapid mineral characterisation, addressing mineral exploration and mining challenges. Shortwave (SWIR), mid (MIR) and thermal (TIR) infrared reflectance spectra are collected in a wide range of environments and scales, with instrumentation ranging from spaceborne, airborne, field and drill core sensors to IR microscopy. However, interpretation of reflectance spectra is, due to the abundance of potential vibrational modes in mineral assemblages, non-trivial and requires a thorough understanding of the potential factors contributing to the reflectance spectra. In order to close the gap between understanding mineral-diagnostic absorption features and efficient interpretation of reflectance spectra, an up-to-date overview of major vibrational modes of rock-forming minerals in the SWIR, MIR and TIR is provided. A series of scripts are proposed that allow the extraction of the relative intensity or wavelength position of single absorption and other mineral-diagnostic features. Binary discrimination diagrams can assist in rapidly evaluating mineral assemblages, and relative abundance and chemical composition of key vector minerals, in hydrothermal ore deposits. The aim of this contribution is to make geologically relevant information more easily extractable from reflectance spectra, enabling the mineral resources and geoscience communities to realise the full potential of hyperspectral sensing technologies.

scholarly journals Evolution of the hedgehog Gene Family

Genetics ◽  
1996 ◽  
Vol 142 (3) ◽  
pp. 965-972 ◽  
Author(s):  
Sudhir Kumar ◽  
Kristi A Balczarek ◽  
Zhi-Chun Lai
Keyword(s):  
Intercellular Communication ◽  
Short Range ◽  
Gene Duplications ◽  
Future Directions ◽  
Amino Terminal ◽  
Terminal Fragment ◽  
Carboxyl Terminal ◽  
Multicellular Organisms ◽  
Amino Terminal Fragment

Abstract Effective intercellular communication is an important feature in the development of multicellular organisms. Secreted hedgehog (hh) protein is essential for both long- and short-range cellular signaling required for body pattern formation in animals. In a molecular evolutionary study, we find that the vertebrate homologs of the Drosophila hh gene arose by two gene duplications: the first gave rise to Desert hh, whereas the second produced the Indian and Sonic hh genes. Both duplications occurred before the emergence of vertebrates and probably before the evolution of chordates. The amino-terminal fragment of the hh precursor, crucial in long- and short-range intercellular communication, evolves two to four times slower than the carboxyl-terminal fragment in both Drosophila hh and its vertebrate homologues, suggesting conservation of mechanism of hh action in animals. A majority of amino acid substitutions in the amino- and carboxyl-terminal fragments are conservative, but the carboxyl-terminal domain has undergone extensive insertion-deletion events while maintaining its autocleavage protease activity. Our results point to similarity of evolutionary constraints among sites of Drosophila and vertebrate hh homologs and suggest some future directions for understanding the role of hh genes in the evolution of developmental complexity in animals.

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