scholarly journals Compositional Variation and Color Diversity of Glass Beads from a 4th Century Tomb Complex in Korea

2021 ◽  
Vol 11 (11) ◽  
pp. 5233
Author(s):  
Jeongeun Yi ◽  
Hye-Ri Yang ◽  
Chan-Hee Lee

This study investigated the chemical compositions and color diversity of various colored glass beads excavated from the 4th century Suchonri site in Korea. The results reveal that the compositions of the coloring materials and stabilizers contain black or white impurities, and there are clear boundaries in the weathered surfaces within the glass beads. The weathered side turned brown, the amounts of Na and K are greater, and there is a decrease in alkali elements. The fragments in blue-green beads from tomb No. 11 were identified as potash glass, whereas the rest of the samples were soda glass. Analysis of the coloration elements identified Fe and Cu in all glass beads, and it was estimated that both elements resulted in a green color. Fe was predicted to cause a brown color. The results of the study may be used not only for scientific interpretation of the relics from the Suchonri tomb complex but also as archaeological evidence that may contribute to the material characterization of the ancient glass from the Korean peninsula.

2012 ◽  
Vol 76 (2) ◽  
pp. 133-140 ◽  
Author(s):  
Qinghui Li ◽  
Song Liu ◽  
Bomin Su ◽  
Hongxia Zhao ◽  
Qiang Fu ◽  
...  

Archaeometry ◽  
2013 ◽  
Vol 56 (4) ◽  
pp. 601-624 ◽  
Author(s):  
Q. H. Li ◽  
S. Liu ◽  
H. X. Zhao ◽  
F. X. Gan ◽  
P. Zhang
Keyword(s):  

2012 ◽  
Vol 1451 ◽  
pp. 117-122 ◽  
Author(s):  
Jaesung Lee ◽  
Philip X.-L. Feng ◽  
Anupama B. Kaul

ABSTRACTWe report on the material characterization of carbon nanofibers (CNFs) which are assembled into a three-dimensional (3D) configuration for making new nanoelectromechanical systems (NEMS). High-resolution scanning electron microscopy (SEM) and x-ray electron dispersive spectroscopy (XEDS) are employed to decipher the morphology and chemical compositions of the CNFs at various locations along individual CNFs grown on silicon (Si) and refractory nitride (NbTiN) substrates, respectively. The measured characteristics suggest interesting properties of the CNF bodies and their capping catalyst nanoparticles, and growth mechanisms on the two substrates. Laser irradiation on the CNFs seems to cause thermal oxidation and melting of catalyst nanoparticles. The structural morphology and chemical compositions of the CNFs revealed in this study should aid in the applications of the CNFs to nanoelectronics and NEMS.


2018 ◽  
Author(s):  
Devon Jakob ◽  
Le Wang ◽  
Haomin Wang ◽  
Xiaoji Xu

<p>In situ measurements of the chemical compositions and mechanical properties of kerogen help understand the formation, transformation, and utilization of organic matter in the oil shale at the nanoscale. However, the optical diffraction limit prevents attainment of nanoscale resolution using conventional spectroscopy and microscopy. Here, we utilize peak force infrared (PFIR) microscopy for multimodal characterization of kerogen in oil shale. The PFIR provides correlative infrared imaging, mechanical mapping, and broadband infrared spectroscopy capability with 6 nm spatial resolution. We observed nanoscale heterogeneity in the chemical composition, aromaticity, and maturity of the kerogens from oil shales from Eagle Ford shale play in Texas. The kerogen aromaticity positively correlates with the local mechanical moduli of the surrounding inorganic matrix, manifesting the Le Chatelier’s principle. In situ spectro-mechanical characterization of oil shale will yield valuable insight for geochemical and geomechanical modeling on the origin and transformation of kerogen in the oil shale.</p>


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2160
Author(s):  
Alexander Bogdanov ◽  
Ekaterina Kaneva ◽  
Roman Shendrik

Elpidite belongs to a special group of microporous zirconosilicates, which are of great interest due to their capability to uptake various molecules and ions, e.g., some radioactive species, in their structural voids. The results of a combined electron probe microanalysis and single-crystal X-ray diffraction study of the crystals of elpidite from Burpala (Russia) and Khan-Bogdo (Mongolia) deposits are reported. Some differences in the chemical compositions are observed and substitution at several structural positions within the structure of the compounds are noted. Based on the obtained results, a detailed crystal–chemical characterization of the elpidites under study was carried out. Three different structure models of elpidite were simulated: Na2ZrSi6O15·3H2O (related to the structure of Russian elpidite), partly Ca-replaced Na1.5Ca0.25ZrSi6O15·2.75H2O (close to elpidite from Mongolia), and a hypothetical CaZrSi6O15·2H2O. The vibration spectra of the models were obtained and compared with the experimental one, taken from the literature. The strong influence of water molecule vibrations on the shape of IR spectra of studied structural models of elpidite is discussed in the paper.


2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Dong Wang ◽  
Rui Wen ◽  
Julian Henderson ◽  
Xingjun Hu ◽  
Wenying Li

AbstractThe Hetian Bizili site in Lop County, located on the southern route of the Silk Road in Xinjiang, China, was a trade and cultural hub between the East and the West in ancient times. In 2016, a large number of glass beads were unearthed from the 40 tombs excavated on this site. In this study we determined the chemical compositions and manufacturing technology of bodies and decorations of twelve glass beads from the M5 tomb of Bizili by using LA-ICP-AES, EDXRF, Raman Spectrometry, and SR-μCT. The chemical compositions of the beads were all Na2O–CaO–SiO2, with plant ash mainly used as a flux. Lead antimonate and lead stannate were used as the opacifying agents. We detected elevated levels of boron and high levels of phosphorus in some beads: this is discussed in the context of the type of flux used and the possible use of a P-rich opacifier. Some of the beads with high contents of aluminum may potentially come from Pakistan. In terms of manufacturing technology, the craftsmen made ‘eye’ beads in different ways and also trail decorated beads.


Lubricants ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 29
Author(s):  
Carl F. O. Dahlberg ◽  
Jonas Faleskog ◽  
Per-Lennart Larsson

Correlation of sharp indentation problems is examined theoretically and numerically. The analysis focuses on elastic-plastic pressure-sensitive materials and especially the case when the local plastic zone is so large that elastic effects on the mean contact pressure will be small or negligible as is the case for engineering metals and alloys. The results from the theoretical analysis indicate that the effect from pressure-sensitivity and plastic strain-hardening are separable at correlation of hardness values. This is confirmed using finite element methods and closed-form formulas are presented representing a pressure-sensitive counterpart to the Tabor formula at von Mises plasticity. The situation for the relative contact area is more complicated as also discussed.


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