The Microstructure of National Bureau of Standards Reference Fly Ashes

1988 ◽  
Vol 136 ◽  
Author(s):  
J. C. Qian ◽  
E. E. Lachowski ◽  
F. P. Glasser
Keyword(s):  
Electron Microscopy ◽  
Phase Separation ◽  
Fly Ash ◽  
Glassy Phase ◽  
Analytical Electron Microscopy ◽  
Standard Reference Materials ◽  
Chemical Compositions ◽  
National Bureau ◽  
Fly Ashes ◽  
High Iron Content

ABSTRACTA suite of three fly ashes, National Bureau of Standards* Standard Reference Materials (SRMs) 2689, 2690 and 2691, was studied by transmission electron microscopy and by analytical electron microscopy (aem): sample preparation techniques are described. The chemical compositions of the glassy phase, analyzed by aem, showed a wide dispersion of values although the mean composition of the glass remained close to that of the whole fly ash.The microstructure of these materials is complex: besides crystalline inclusions, the aluminasilica glasses have undergone phase separation on a nanometer scale, and consist of two glassy phases. Since liquid-liquid phase separation has also been found in British fly ashes, it appears to be a characteristic feature of the glassy phase in Class F ashes and is also encountered in occasional Al-Si rich particles in Class C ashes. High iron content glass was found in fly ash SRM 2689, and its phase separation and crystallization were investigated.

X-Ray Powder Diffraction For Studying the Mineralogy of fly ash

1987 ◽  
Vol 113 ◽  
Author(s):  
Gregory I. McCarthy
Keyword(s):  
Fly Ash ◽  
Powder Diffraction ◽  
Reference Materials ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Fly Ashes ◽  
X Ray ◽  
High Calcium

ABSTRACTA brief summary of the use of x-ray powder diffraction for studying the mineralogy of fly ash is presented. Mineralogies of low-, intermediate- and high-calcium fly ashes are discussed and illustrated by results from XRD characterization of U.S. National Bureau of Standards fly ash Standard Reference Materials.

Analytical Electron Microscopy of Ion-Implanted Metals

1985 ◽  
Vol 43 ◽  
pp. 282-285
Author(s):  
D.I. Potter ◽  
M. Ahmed ◽  
K. Ruffing
Keyword(s):  
Electron Microscopy ◽  
Ion Implantation ◽  
Friction And Wear ◽  
Analytical Electron Microscopy ◽  
Chemical Compositions ◽  
Surface Chemical ◽  
Near Surface ◽  
The Past ◽  
Analytical Electron ◽  
Property Changes

Ion implantation, used extensively for the past decade in fabricating semiconductor devices, now provides a unique means for altering the near-surface chemical compositions and microstructures of metals. These alterations often significantly improve physical properties that depend on the surface of the material; for example, catalysis, corrosion, oxidation, hardness, friction and wear. Frequently the mechanisms causing these beneficial alterations and property changes remain obscure and much of the current research in the area of ion implantation metallurgy is aimed at identifying such mechanisms. Investigators thus confront two immediate questions: To what extent is the chemical composition changed by implantation? What is the resulting microstructure? These two questions can be investigated very fruitfully with analytical electron microscopy (AEM), as described below.

TEM/AEM characterization of fine-grained clay minerals in very-low-grade rocks: Evaluation of contamination by empa involving celadonite family minerals

1996 ◽  
Vol 54 ◽  
pp. 694-695
Author(s):  
Gejing Li ◽  
D. R. Peacor ◽  
D. S. Coombs ◽  
Y. Kawachi
Keyword(s):  
Electron Microscopy ◽  
Volcanic Rocks ◽  
Analytical Electron Microscopy ◽  
Metamorphic Rocks ◽  
New Mineral ◽  
Chemical Compositions ◽  
Low Grade ◽  
Fine Grained ◽  
Depth Analysis ◽  
Mineral Aggregates

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.

Elemental concentrations in the National Bureau of Standards' environmental coal and fly ash Standard Reference Materials

1975 ◽  
Vol 47 (7) ◽  
pp. 1102-1109 ◽  
Author(s):  
J. M. Ondov ◽  
W. H. Zoller ◽  
Ilhan. Olmez ◽  
N. K. Aras ◽  
G. E. Gordon ◽  
...  
Keyword(s):  
Fly Ash ◽  
Reference Materials ◽  
Standard Reference Materials ◽  
National Bureau ◽  
Elemental Concentrations

The Influence of Different Brass Pretreatments on Rubber-Metal Bonding: Investigated by Analytical Electron Microscopy

1993 ◽  
Vol 66 (5) ◽  
pp. 837-848 ◽  
Author(s):  
T. Kretzschmar ◽  
K. Hummel ◽  
F. Hofer
Keyword(s):  
Electron Microscopy ◽  
Cross Sections ◽  
Analytical Electron Microscopy ◽  
Chemical Compositions ◽  
Surface Layers ◽  
Thin Foils ◽  
Fecl3 Solution ◽  
Analytical Electron ◽  
Crystallographic Structures ◽  
Preparation Techniques

Abstract Brass samples (thin foils or plates) were pretreated either by etching with aqueous HC1 or by rubbing with emery cloth. A mixture of cis-l,4-polybutadiene with sulfur and N,N-dicyclohexyl-2-benzothiazylsulfenamide was vulcanized in contact with the brass surfaces. The bonding layers were investigated by analytical electron microscopy (AEM). Two preparation techniques for AEM were used, namely cryo-ultramicrotomy to obtain cross sections (applied to foils), or separating ultrathin surface layers with an aqueous HCl/FeCl3 solution (applied to plates). Across the bonding layers, various crystallographic structures and chemical compositions were found, depending on the pretreatment of the brass.

scholarly journals COMPARATIVE STUDY OF MORPHOLOGY OF VARIOUS FLY ASHES AND POND ASHES FROM DIFFERENT THERMAL POWER STATIONS IN MONGOLIA

2016 ◽  
pp. 5-10 ◽  
Author(s):  
Uyat Bayanzul ◽  
Jadambaa Temuujin ◽  
Amgalan Minjigmaa ◽  
Amgalan Bekhbaatar ◽  
B Battsetseg ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Specific Surface ◽  
Power Plants ◽  
Thermal Power ◽  
Bottom Ash ◽  
Area Measurement ◽  
Chemical Compositions ◽  
Fly Ashes ◽  
Power Stations ◽  
Thermal Power Stations

In Mongolia coal fired thermal power stations produce over 90% of the country’s electricity. Three thermal power stations located in Ulaanbaatar city produce more than 80% of all electricity produced in Mongolia. The annual output of fly ash and bottom ash from these thermal power stations is about 600,000 tons. The thermal power plants in Ulaanbaatar city use coal from Baganuur and Shivee-Ovoo deposits. This research was conducted to compare morphologies of various fly ashes and pond ashes from TPS in Mongolia. Fly ashes from TPS4 and pond ashes from TPS3 and TPS4 of Ulaanbaatar city were characterized by x-ray fluorescence (XRF), transmission electron microscopy (TEM), laser particle size distribution analyzer, specific surface area measurement (BET), and scanning electron microscopy (SEM). The chemical compositions of the fly ashes and pond ashes indicate that they are class C ashes. Specific surface areas of the fly ashes and pond ashes varied from 1.04 to 25.2 m2/g. Radiation measurements that were performed by γ-spectroscopy indicate that the radium equivalent changed from 292 to 761 Bq/kg in the various ashes.  

Preparation and Characterization of Three New NBS Fly Ash Standard Reference Materials

1985 ◽  
Vol 65 ◽  
Author(s):  
Howard M. Kanare
Keyword(s):  
Fly Ash ◽  
Reference Materials ◽  
Chemical Elements ◽  
Standard Reference Materials ◽  
Physical Analysis ◽  
National Bureau ◽  
Loss On Ignition ◽  
New Methods ◽  
The U.S

Three new fly ash standard reference materials (SRM's) have been produced by CTL under contract with the U.S. National Bureau of Standards (NBS). Each unit of the SRM's consists of approximately ten grams of well-blended fly ash hermetically sealed in a glass vial. Twenty-thousand vials of each SRM were produced. The SRM's will be certified for major and minor chemical elements, loss on ignition, and for the percentage residue on the No. 325 standard sieve. The SRM's are suitable for use in developing new methods of chemical and physical analysis, for checking the performance of instruments and analysts, and for research into the composition and properties of fly ash.

Influence of Lignite Bottom Ash on Pyroplastic Deformation of Stoneware Ceramic Tiles

2018 ◽  
Vol 766 ◽  
pp. 264-269 ◽  
Author(s):  
Tarit Prasartseree ◽  
Thanakorn Wasanapiarnpong ◽  
Charusporn Mongkolkachit ◽  
Noppasint Jiraborvornpongsa
Keyword(s):  
Fly Ash ◽  
Water Absorption ◽  
High Temperatures ◽  
Ceramic Tile ◽  
Glassy Phase ◽  
Raw Materials ◽  
Bottom Ash ◽  
High Strength ◽  
Chemical Compositions ◽  
Ceramic Tiles

Electricity generation at Mae Moh Power Plant in Lampang, Thailand, uses lignite as fuel. The output is 3.0 to 3.5 million tons of fly ash per year and 1.5 to 2.0 million tons of bottom ash per year. Fly ash is widely used in concrete application but for bottom ash, it is not very useful. When considering the phase of bottom ash containing quartz, anorthite and hematite, it was found that there are suitable chemical compositions for replacement of raw materials in ceramic tile. Generally, the stoneware tiles are composed of quartz, mullite, feldspar, and glass phase. Water absorption of stoneware ceramic tiles is below 5%, high strength, fire resistance, and low warpage. Firing or sintering at rather high temperature as 1000-1250 °C is the manufacturing process for this type of tile. The changes in crystal structure and glassy phase formation in tile texture during sintering will be often result the tile to warpage or bent. The more or less lean depends on the viscosity of the glassy phase that occurs at high temperatures in the tile if less viscosity will cause higher warping rate that effect on the shape, and quality of the workpiece. The research has reported that anorthite phase improves the viscosity of a liquid phase or glassy phase when the tile is sintering at high temperatures and lead to high density and low water absorption. This research is interested in studying the effect of using lignite bottom ash as an ingredient in ceramic tile texture to produce low water absorption type by analyzing the effect of percentage of lignite bottom ash to warpage and important properties of ceramic tiles.

scholarly journals Developing Standard Reference Materials for Analytical Electron Microscopy

2011 ◽  
Vol 17 (S2) ◽  
pp. 840-841
Author(s):  
E Steel ◽  
J Davis ◽  
A Herzing
Keyword(s):  
Electron Microscopy ◽  
Reference Materials ◽  
Analytical Electron Microscopy ◽  
Standard Reference Materials ◽  
Analytical Electron

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

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