Investigation of Urtite as an Analog of Waste Slag from a Plasma Shaff Furnace

1995 ◽  
Vol 412 ◽  
Author(s):  
S. A. Dmitriev ◽  
S. V. Stefanovsky
Keyword(s):  
Radioactive Waste ◽  
Electron Probe ◽  
Nepheline Syenite ◽  
Shaft Furnace ◽  
Alkali Feldspar ◽  
Chemical Compositions ◽  
Natural Analog ◽  
First Approximation ◽  
Geochemical Investigation

abstractMineralogical-geochemical investigation of a sample of nepheline syenite (urtite) as a natural analog of final radioactive waste form has been performed. The specimen of urtite consists of nepheline, alkali feldspar, pyroxene, sphene, apatite and minor magnetite and amphibole. As a first approximation, urtite simulates the mineral composition of waste slag produced in a plasma shaft furnace at SIA “Radon”. Determination of chemical compositions of the minerals by electron-probe microanalysis has shown that the main phases that hosted radionuclides and their geochemical analogs are as follows: nepheline (Rb and probably Cs), feldspar (Ba), sphene (Zr, Nb, REE, and actinides) and apatite (Sr, REE, and actinides).

scholarly journals Some Aspects of Chemical Abundance Determinations in Planetary Nebulae

1978 ◽  
Vol 76 ◽  
pp. 225-233 ◽  
Author(s):  
Lawrence H. Aller
Keyword(s):  
Order Approximation ◽  
Planetary Nebulae ◽  
Chemical Compositions ◽  
Zeroth Order ◽  
Chemical Abundance ◽  
Zeroth Order Approximation ◽  
Gaseous Nebulae ◽  
First Approximation

The determination of the chemical compositions of gaseous nebulae in general and of planetary nebulae in particular is a difficult undertaking. The zeroth-order approximation is straightforward, the first approximation is challenging, and the second approximation is almost intractable.

Quantitative energy-dispersive electron probe X-ray microanalysis of individual particles

2006 ◽  
Vol 21 (2) ◽  
pp. 140-144 ◽  
Author(s):  
Chul-Un Ro
Keyword(s):  
Quantitative Determination ◽  
Electron Probe ◽  
Loess Soil ◽  
Energy Dispersive ◽  
Particle Analysis ◽  
Chemical Compositions ◽  
Carbonaceous Particles ◽  
X Ray ◽  
Individual Particles

An electron probe X-ray microanalysis (EPMA) technique using an energy-dispersive X-ray detector with an ultrathin window, designated low-Z particle EPM, has been developed. The low-Z particle EPMA allows the quantitative determination of concentrations of low-Z elements, such as C, N, and O, as well as higher-Z elements that can be analyzed by conventional energy-dispersive EPMA. The quantitative determination of low-Z elements (using full Monte Carlo simulations, from the electron impact to the X-ray detection) in individual environmental particles has improved the applicability of single-particle analysis, especially in atmospheric environmental aerosol research; many environmentally important atmospheric particles, e.g. sulfates, nitrates, ammonium, and carbonaceous particles, contain low-Z elements. The low-Z particle EPMA was applied to characterize loess soil particle samples of which the chemical compositions are well defined by the use of various bulk analytical methods. Chemical compositions of the loess samples obtained from the low-Z particle EPMA turn out to be close to those from bulk analyses. In addition, it is demonstrated that the technique can also be used to assess the heterogeneity of individual particles.

Reduction of Potassium in Kidney Proximal Tubules to Aid in Electron Probe X-Ray Microanalysis of Calcium

1985 ◽  
Vol 43 ◽  
pp. 474-475
Author(s):  
A. LeFurgey ◽  
P. Ingram ◽  
L.J. Mandel
Keyword(s):  
Smooth Muscle ◽  
Proximal Tubule ◽  
Electron Probe ◽  
Clinical Applications ◽  
Proximal Tubules ◽  
Rabbit Kidney ◽  
Target Cells ◽  
X Ray ◽  
Freeze Dried

For quantitative determination of subcellular Ca distribution by electron probe x-ray microanalysis, decreasing (and/or eliminating) the K content of the cell maximizes the ability to accurately separate the overlapping K Kß and Ca Kα peaks in the x-ray spectra. For example, rubidium has been effectively substituted for potassium in smooth muscle cells, thus giving an improvement in calcium measurements. Ouabain, a cardiac glycoside widely used in experimental and clinical applications, inhibits Na-K ATPase at the cell membrane and thus alters the cytoplasmic ion (Na,K) content of target cells. In epithelial cells primarily involved in active transport, such as the proximal tubule of the rabbit kidney, ouabain rapidly (t1/2= 2 mins) causes a decrease2 in intracellular K, but does not change intracellular total or free Ca for up to 30 mins. In the present study we have taken advantage of this effect of ouabain to determine the mitochondrial and cytoplasmic Ca content in freeze-dried cryosections of kidney proximal tubule by electron probe x-ray microanalysis.

Electron microprobe study of turquoise-group solid solutions in the Neyshabour and Meydook mines, northeast and southern Iran

2020 ◽  
Vol 58 (1) ◽  
pp. 71-83
Author(s):  
Elahe Mansouri Gandomani ◽  
Nematollah Rashidnejad-Omran ◽  
Amir Emamjomeh ◽  
Pietro Vignola ◽  
Tahereh Hashemzadeh
Keyword(s):  
Solid Solution ◽  
Solid Solutions ◽  
Electron Microprobe ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Major Elements ◽  
Point Of View ◽  
Chemical Compositions ◽  
Light Blue ◽  
Quaternary Solid Solution

ABSTRACT Turquoise, CuAl6(PO4)4(OH)8·4H2O, belongs to the turquoise group, which consists of turquoise, chalcosiderite, aheylite, faustite, planerite, and UM1981-32-PO:FeH. In order to study turquoise-group solid solutions in samples from the Neyshabour and Meydook mines, 17 samples were selected and investigated using electron probe microanalysis. In addition, their major elements were compared in order to evaluate the feasibility of distinguishing the provenance of Persian turquoises. The electron microprobe data show that the studied samples are not constituted of pure turquoise (or any other pure endmember) and belong, from the chemical point of view, to turquoise-group solid solutions. In a turquoise–planerite–chalcosiderite–unknown mineral quaternary solid solution diagram, the chemical compositions of the analyzed samples lie along the turquoise–planerite line with minor involvement of chalcosiderite and the unknown mineral. Among light blue samples with varying hues and saturations from both studied areas, planerite is more abundant among samples from Meydook compared with samples from Neyshabour. Nevertheless, not all the light blue samples are planerite. This study demonstrates that distinguishing the deposit of origin for isochromatic blue and green turquoises, based on electron probe microanalysis method and constitutive major elements, is not possible.

Simultaneous Determination of Several Elements by Spectrochemical Addition Method … (II) (Tabulation of Analytical Value)

1968 ◽  
Vol 22 (6) ◽  
pp. 749-752 ◽  
Author(s):  
Isoo Masuda ◽  
Tamon Inouye
Keyword(s):  
Simultaneous Determination ◽  
Order Approximation ◽  
Analytical Data ◽  
Zero Order ◽  
Dilution Factor ◽  
Improved Method ◽  
Addition Method ◽  
Zero Order Approximation ◽  
First Approximation

An improved method for the tabulation of analytical data, obtained by addition and successive dilution procedures for spectrochemical analysis, is presented. The author's previous work shows that the solution of the first approximation diverges at some dilution factor smaller than unity when the slope of the working curve of added series is greater than that of unadded series. By obtaining the distance between this position and the origin, and taking it as a correction factor for zero-order approximation, tabulation of the analytical value, in the case of β>α, is carried out. One parameter of the calculation is deleted by normalizing the spectral intensity; therefore, the tabulation can be simplified.

Graphical-Numerical Solution of Problems of Saint-Venant Torsion and Bending

1953 ◽  
Vol 20 (3) ◽  
pp. 321-326
Author(s):  
B. A. Boley
Keyword(s):  
Cross Section ◽  
Stress Function ◽  
Arbitrary Cross Section ◽  
Successive Approximations ◽  
Shear Stresses ◽  
Shearing Stress ◽  
First Approximation ◽  
Difference Form ◽  
Bending Of Beams

Abstract A simple successive-approximations procedure for the solution of the problems of Saint-Venant torsion and bending of beams of arbitrary cross section is presented. The shear stresses in a cross section of the beam are first calculated from the formulas valid for thin-walled sections, on the basis of an assumed set of lines of shearing stress. From these a first approximation to the stress function of either the torsion or the bending problem is found. The second approximation to the stress function is then obtained from the governing equation of the problem, expressed in finite-difference form; this in turn allows the determination of an improved set of lines of shearing stress, and hence of the shearing stress itself. The procedure can be repeated until the results of two successive steps are sufficiently close. Applications are presented for a beam cross section for which the exact solutions are known, and it is shown that no further difficulties arise in applications to more complicated shapes.

Utilization of open pit burned household waste ash – a feasibility study in Dhaka

2014 ◽  
Vol 32 (5) ◽  
pp. 397-405
Author(s):  
Md. Obaidul Haque ◽  
Ahmed Sharif
Keyword(s):  
Room Temperature ◽  
Raw Materials ◽  
Bottom Ash ◽  
Open Pit ◽  
Household Waste ◽  
Chemical Compositions ◽  
Muffle Furnace ◽  
Clay Bricks ◽  
Peripheral Area

Informal incineration or open pit burning of waste materials is a common practice in the peripheral area of Dhaka, one of the fastest growing mega-cities in the world. This study deals with the effect of open pit burned (i.e. open burned) household waste bottom ash on fired clay bricks. Between 0 to 50% (by weight) of open pit burned household waste bottom ash was mixed with clay to make bricks. The molded specimens were air-dried at room temperature for 24 h and then oven dried at 100 °C for another 24 h to remove the water. The raw bricks were fired in a muffle furnace to a designated temperature (800, 900 and 1000 °C, respectively). The firing behaviour (mechanical strength, water absorption and shrinkage) was determined. The microstructures, phase compositions and leachates were evaluated for bricks manufactured at different firing temperatures. These results demonstrate that open pit burned ash can be recycled in clay bricks. This study also presents physical observations of the incinerated ash particles and determination of the chemical compositions of the raw materials by wet analysis. Open pit burned ash can be introduced easily into bricks up to 20% wt. The concentrations of hazardous components in the leachates were below the standard threshold for inert waste category landfill and their environmental risk during their use-life step can be considered negligible.

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