Tribo-Chemistry of Particles Collected During In Situ Gasification of Texas Lignite

1997 ◽  
Author(s):  
Houshang Masudi ◽  
Richard B. Griffin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Size Range ◽  
Chemical Elements ◽  
Energy Dispersive ◽  
Particle Size Range ◽  
X Ray ◽  
Sem Micrograph ◽  
Scanning Electron

Particles collected during in situ gasification of Texas lignite experiments were analyzed for chemical elements. Results obtained by energy dispersive x-ray analysis revealed that the dominating elements in both particles and lignite are Si, S, Al, Fe, and Ca. The concentration of these elements depends on the selected region and varies within the particle size range. Semi-quantitative analysis revealed the same results. This paper presents the scanning electron microscopy (SEM) micrograph and energy dispersive x-ray analysis (EDXA) for particles and Rockdale lignite.

The Application of Scanning Electron Microscopy with Energy-Dispersive X-Ray Spectroscopy (SEM-EDX) in Ancient Dental Calculus for the Reconstruction of Human Habits

2017 ◽  
Vol 23 (6) ◽  
pp. 1207-1213 ◽  
Author(s):  
Dana Fialová ◽  
Radim Skoupý ◽  
Eva Drozdová ◽  
Aleš Paták ◽  
Jakub Piňos ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Elements ◽  
Energy Dispersive ◽  
Dental Calculus ◽  
X Ray ◽  
A Charge ◽  
High Degree ◽  
The 19Th Century ◽  
Scanning Electron

AbstractThe great potential of scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) is in detection of unusual chemical elements included in ancient human dental calculus to verify hypotheses about life and burial habits of historic populations and individuals. Elemental spectra were performed from archeological samples of three chosen individuals from different time periods. The unusual presence of magnesium, aluminum, and silicon in the first sample could confirm the hypothesis of high degree of dental abrasion caused by particles from grinding stones in flour. In the second sample, presence of copper could confirm that bronze jewelery could lie near the buried body. The elemental composition of the third sample with the presence of lead and copper confirms the origin of individual to Napoleonic Wars because the damage to his teeth could be explained by the systematic utilization of the teeth for the opening of paper cartridges (a charge with a dose of gunpowder and a bullet), which were used during the 18th and the 19th century AD. All these results contribute to the reconstruction of life (first and third individual) and burial (second individual) habits of historic populations and individuals.

Scanning Electron Microscopy (SEM) Energy Dispersive X-ray Spectroscopy (EDS) Mapping and In-situ Observation of Carbonization of Culms of Bambusa Multiplex

2018 ◽  
Vol 24 (2) ◽  
pp. 156-162
Author(s):  
Visittapong Yordsri ◽  
Chanchana Thanachayanont ◽  
Shunsuke Asahina ◽  
Yuuki Yamaguchi ◽  
Masahiro Kawasaki ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silicon Oxide ◽  
Skin Layer ◽  
Energy Dispersive ◽  
In Situ Observation ◽  
Bamboo Culm ◽  
X Ray ◽  
Scanning Electron

AbstractGreen culms of bamboo and charcoal of Bambusa multiplex were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) mapping. A dynamic observation of the initial stage of carbonization was also performed in-situ by heating a radial longitudinal section of the bamboo culm at a rate of 20°C/min up to 500°C. EDS mapping of the green bamboo culms detected Si signals in the harder cells such as the epidermis (Ep), cortex (Cor) and vascular bundle sheath (Bs) and between these cells as silicon oxide particles. Appreciable morphological change of the cells occurred in a temperature range of about 300–400°C due to the decomposition of cellulose that is the main component of the bamboo cells. The charcoal of the bamboo culm has a skin layer which originates from the Ep and Cor and the main central cylinder with many openings that originate from the expanded xylem and phloem holes. During carbonization, the Si atoms in the Ep and Cor were segregated as thin silicon oxide layers onto both the sides of the skin layer and the Si included in the Bs fibers and parenchyma cells accumulated near the walls of the openings.

Structural Characterization of Gallbladder Stones Using Energy Dispersive X-ray Spectroscopy and X-ray Diffraction

2018 ◽  
Vol 21 (7) ◽  
pp. 495-500 ◽  
Author(s):  
Hassan A. Almarshad ◽  
Sayed M. Badawy ◽  
Abdalkarem F. Alsharari
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Energy Dispersive ◽  
Spectroscopic Techniques ◽  
X Ray Diffraction ◽  
Major Health Problem ◽  
X Ray ◽  
Gallbladder Stones ◽  
Pure Cholesterol ◽  
Scanning Electron

Aim and Objective: Formation of the gallbladder stones is a common disease and a major health problem. The present study aimed to identify the structures of the most common types of gallbladder stones using X-ray spectroscopic techniques, which provide information about the process of stone formation. Material and Method: Phase and elemental compositions of pure cholesterol and mixed gallstones removed from gallbladders of patients were studied using energy-dispersive X-ray spectroscopy combined with scanning electron microscopy analysis and X-ray diffraction. Results: The crystal structures of gallstones which coincide with standard patterns were confirmed by X-ray diffraction. Plate-like cholesterol crystals with laminar shaped and thin layered structures were clearly observed for gallstone of pure cholesterol by scanning electron microscopy; it also revealed different morphologies from mixed cholesterol stones. Elemental analysis of pure cholesterol and mixed gallstones using energy-dispersive X-ray spectroscopy confirmed the different formation processes of the different types of gallstones. Conclusion: The method of fast and reliable X-ray spectroscopic techniques has numerous advantages over the traditional chemical analysis and other analytical techniques. The results also revealed that the X-ray spectroscopy technique is a promising technique that can aid in understanding the pathogenesis of gallstone disease.

Identification of Nd163 phase in melt-textured NdBa2Cu3O7−δ bulk samples

2003 ◽  
Vol 18 (9) ◽  
pp. 2050-2054 ◽  
Author(s):  
Marcello Gombos ◽  
Vicente Gomis ◽  
Anna Esther Carrillo ◽  
Antonio Vecchione ◽  
Sandro Pace ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Room Temperature ◽  
Polarized Light ◽  
Energy Dispersive ◽  
X Ray ◽  
Spontaneous Formation ◽  
The Stability ◽  
Scanning Electron

In this work, we report on the observation of Nd1Ba6Cu3O10,5 (Nd163) phase of the NdBaCuO system in melt-textured Nd123 bulk samples grown from a mixture of Nd123 and Nd210 phase powders. The observation was performed with polarized light optical microscopy and scanning electron microscopy–energy dispersive x-ray analyses. Images of the identified phase crystals show an aspect quite different from Nd422 crystals. Unexpectedly, Nd163 was individuated, even in “pure” Nd123 samples. Moreover, after long exposure to air, Nd163 disappeared completely in samples synthesized from powders containing Nd210. Thermogravimetry analyses of powders show that the stability of this phase in air is limited to temperatures higher than 900 °C, so Nd163 is unstable and highly reactive at room temperature. Moreover, an explanation of the observation of Nd163 in Nd210 free samples, based on the spontaneous formation of Nd163 phase in a Nd123 melt, is proposed.

Effect of TiC on coarsening and macrosegregation of Al–Bi alloys

2020 ◽  
Vol 111 (7) ◽  
pp. 607-615
Author(s):  
Congmin Li ◽  
Yanguo Yin ◽  
Ming Xu ◽  
Jianfeng Cheng ◽  
Lan Shen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Heterogeneous Nucleation ◽  
Self Assembly ◽  
Holding Time ◽  
Energy Dispersive ◽  
Melt Temperature ◽  
X Ray ◽  
Minority Phase ◽  
Scanning Electron

Abstract The microstructures of an Al-Bi immiscible alloy and the corresponding composites containing TiC (1 wt.% and 2 wt.%) were explored for melt temperatures of 800 °C, 850 °C, and 900°C. It was demonstrated that serious coarsening and macrosegregation of Bi-rich minority phase particles occurred, which was slightly alleviated by increasing the melt temperature from 800 °C to 900 °C. By adding TiC particles, the coarsening and macrosegregation of Bi-rich minority phase particles were significantly impeded. Scanning electron microscopy and energy-dispersive X-ray spectroscopy revealed that TiC particles were located inside and on the surface of Bi-rich minority phase particles, exhibiting heterogeneous nucleation and self-assembly behaviour. By properly increasing the holding time of the melt, finer and more uniform Bi-rich minority phase particles were obtained.

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