Characterization of high-temperature superconductors by electron microprobe analysis

1992 ◽  
Vol 107 (3-6) ◽  
pp. 273-277 ◽  
Author(s):  
Theodor H. G. Hehenkamp
Keyword(s):  
High Temperature ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
High Temperature Superconductors

scholarly journals CHEMICAL CHARACTERIZATION OF UNCOATED ASBESTOS FIBERS FROM THE LUNGS OF ASBESTOS WORKERS BY ELECTRON MICROPROBE ANALYSIS

1972 ◽  
Vol 20 (9) ◽  
pp. 735-740 ◽  
Author(s):  
ARTHUR M. LANGER ◽  
IVAN B. RUBIN ◽  
IRVING J. SELIKOFF ◽  
FRED D. POOLEY
Keyword(s):  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Chemical Characterization ◽  
Magnesium Content ◽  
Asbestos Fibers ◽  
Magnesium Loss ◽  
Bulk Chemistry ◽  
Asbestos Body

Lung tissues have been obtained from workmen with defined asbestos fiber exposure. These tissues have been prepared by the carbon extraction technique and examined with the electron microprobe analyzer. The uncoated fibers present in these specimens have been chemically characterized and compared with standard reference asbestos samples. The bulk chemistry of the fibers observed in lung tissues is similar to that of the reference fibers so that identification may be made. However, a statistical analysis of the measured emission characteristics from anthophyllite and amosite indicates that some magnesium loss has taken place. This loss appears to correlate with the magnesium content of the fibers. A slight iron increase was also noted in the same fibers, probably related to an incipient asbestos body formation.

A method to overcome the problem of small sample tilts in light element electron microprobe analysis

1990 ◽  
Vol 48 (2) ◽  
pp. 220-221
Author(s):  
Andrew Mackenzie
Keyword(s):  
High Temperature ◽  
Single Crystals ◽  
Surface Quality ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
High Temperature Superconductivity ◽  
Light Element ◽  
Small Sample ◽  
Oxide Superconductors

The technique of electron microprobe analysis is extremely useful in the rapidly changing field of high temperature superconductivity. Since the properties of the oxide superconductors depend strongly on the oxygen concentration, it is important to be able to measure oxygen as accurately as possible. It is particularly useful to know unambiguously the composition of small single crystals, which either grow with good smooth surfaces (for example in the Y-Ba-Cu-O system) or can be easily cleaved (for example the Bi-Sr-Cu-O system) to provide excellent surface quality without polishing. The Bi2+xSr2-x,CuO6±z (BSCO) crystals are extremely soft and layer like, which makes polishing difficult, and another advantage of cleaving is that the crystal does not have to be embedded in epoxy, and can thus be relatively easily removed from its mount for subsequent annealing treatments or other experiments. The disadvantage of mounting in this manner is the existence of small tilt angles, because the thin crystals bend a little when they are cleaved.

scholarly journals Composition of biotite within the Wushan granodiorite, Jiangxi Province, China: Petrogenetic and metallogenetic implications

2014 ◽  
Vol 18 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Qian Dong ◽  
Yangsong Du ◽  
Zhenshan Pang ◽  
Wenrui Miao ◽  
Wei Tu
Keyword(s):  
High Temperature ◽  
Oxygen Fugacity ◽  
Electron Microprobe ◽  
Microprobe Analysis ◽  
Electron Microprobe Analysis ◽  
Copper Deposit ◽  
Jiangxi Province ◽  
Hydrothermal Mineralization ◽  
Type Granite ◽  
Formation Conditions

<p>The Wushan skarn copper deposit is genetically associated with the Wushan granodiorite. In this study, we investigate the petrography and mineralogy of biotites within the Wushan granodiorite. We also determine the formation conditions of these biotites and discuss the significance of these minerals in terms of petrogenesis and mineralization. Electron microprobe analysis shows that biotites within the Wushan granodiorite are Magnesio-biotites that contain relatively high Mg and Ti concentrations and low Fe and Al concentrations. The ionic coefficient of Al<sup>VI</sup> in these biotites ranges from 0.03 to 0.19, with SFeO/(SFeO + MgO) ratios that range from 0.531–0.567 and MgO concentrations that range from 12.80–14.06 wt%. These results indicate that the Wushan granodiorite is an I-type granite. The Wushan biotites crystallized at temperatures (T) of 720°C–750°C, with oxygen fugacity (fO<sub>2</sub>) conditions of –11.6 to –12.5 and pressures (P) of 0.86–1.03 kb. These conditions are indicative of a crystallization depth (H) of 2.84–3.39 km. These data also indicate that the Wushan granodiorite developed under conditions of high temperature and high oxygen fugacity, suggesting that the Wushan granodiorite is prospective for magma-hydrothermal mineralization and that this granodiorite probably contributed to the formation of the Wushan skarn copper deposit.</p><p> </p><p><strong>Resumen</strong></p><p>El depósito de skarn cuprífero de Wushan está asociado genéticamente con la granodiorita de Wushan. En este estudio se investiga la petrografía y mineralogía de biotitas de la granodiorita de Wushan. Se determinan también las condiciones de formación de estas biotitas y se discute la significación de estos minerales en términos de petrogénesis y mineralización. Un análisis de microsonda a electrones muestra que las biotitas de la granodiorita de Wushan son biotitas de magnesio que contienen altas concentracionesrelativas de Mg y Ti y bajas de Fe y Al. El coeficiente icónico de AlVI en estas biotitas oscila entre 0,03 y 0,19, con índices SFeO/(SFeO + MgO) que oscilan entre 0,531-0,567 y concentraciones de MgO que van desde 12,80 a 14,06 wt%. Estos resultados indican que la granodiorita de Wushan es de granito tipo I. Las biotitas de Wushan se cristalizaron a temperaturas (T) de 720°C–750°C, con condiciones de fugacidad del oxígeno (fO2) de -11,6 a -12,5 y presión (P) de O,86 a 1,03 kb. Estas condiciones indican una profundidad de cristalización (H) de 2,84-3,39 kilómetros. Los datos también indican que la granodiorita de Wushan se desarrolló bajo condiciones de alta temperatura y alta fugacidad de oxigeno, lo que sugiere que la granodiorita de Wushan tiene potencial para la mineralización magmática-hidrotérmica y que esta granodiorita probablemente contribuyó a la formación del depósito de skarn cuprífero de Wushan.</p>

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