Peculiarities Of The Diatom Valve Chemical Composition (Inorganic Components) Study By Electron Probe X-Ray Microanalysis

2014 ◽  
Vol 9 (2) ◽  
pp. 65-72
Author(s):  
L.A. Pavlova ◽  
◽  
L.L. Tkachenko ◽  
A.V. Goreglyad ◽  
M.I. Kuzmin ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Electron Probe ◽  
X Ray ◽  
Inorganic Components ◽  
Diatom Valve

A new and versatile computer program for correcting EPMA data

1992 ◽  
Vol 50 (2) ◽  
pp. 1658-1659
Author(s):  
I Farthing ◽  
G Love ◽  
VD Scott ◽  
CT Walker
Keyword(s):  
Chemical Composition ◽  
Computer Program ◽  
Programming Language ◽  
Atomic Number ◽  
Processing Speed ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
Epma Data ◽  
X Ray ◽  
X Ray Absorption

A new computer program has been developed to convert electron probe microanalysis data into accurate measurements of chemical composition. It is menu-based and designed to operate off-line using any IBM PC compatible computer. As shown in the flowchart, fig. 1, the architecture is modular and the programming language adopted is a compilable version of BASIC which possesses much of the processing speed associated with FORTRAN or C. Specimens containing up to fifteen elements, with 4 ≤ Z ≤ 96, can be handled and all the major x-ray lines (Kα, Kβ, Lα, L(β, Mα and Mβ) are available for analysis purposes.The procedure itself is based upon the classical ZAF approach in which corrections for atomic number (Z), x-ray absorption (A), characteristic fluorescence (Fl) and continuum fluorescence (F2) are treated independently. The factors dealing with fluorescence are essentially those of Reed (characteristic) and Springer (continuum) although both contain minor updates. However, the atomic number and absorption factors are the authors' own and the latter, developed from a quadrilateral representation of the x-ray distribution with depth in a solid, distinguishes this program from others.

Thermoelectric Properties of InxCo4-yNiySb12 Skutterudite Compounds

2007 ◽  
Vol 1044 ◽  
Author(s):  
Veronique Da Ros ◽  
Juliusz Leszczynski ◽  
Bertrand Lenoir ◽  
Anne Dauscher ◽  
Christophe Candolfi ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Electrical Resistivity ◽  
Thermal Properties ◽  
Chemical Composition ◽  
Thermoelectric Power ◽  
Thermoelectric Properties ◽  
Electron Probe Microanalysis ◽  
Electron Probe ◽  
X Ray Diffraction ◽  
X Ray

AbstractThe preparation of partially filled n-type InxCo4Sb12 skutterudite compounds has been recently reported. The results were particularly promising, the materials exhibiting a ZT value far higher than one at moderated temperature. In this paper, we propose to investigate another way to tune the electrical and thermal properties by substituting Co atoms by Ni atoms in InxCo4Sb12. InxCo4-yNiySb12 polycrystalline samples have been prepared by a conventional metallurgical route. Structural analyses have been carried out by X-ray diffraction. The chemical composition and micro-homogeneity have been checked by electron probe microanalysis. Measurements of the electrical resistivity, thermoelectric power and thermal conductivity have been performed between 300 and 800 K. The influence of the presence of Ni on the thermoelectric properties of InxCo4Sb12 compounds is presented and discussed.

Change in the Chemical Composition of an Analyzed Object During Low-Voltage Electron Probe X-Ray Spectral Microanalysis

2017 ◽  
Vol 59 (11) ◽  
pp. 1234-1237
Author(s):  
A. Yu. Kuzin ◽  
V. B. Mityukhlyaev ◽  
P. A. Todua ◽  
M. N. Filippov
Keyword(s):  
Chemical Composition ◽  
Electron Probe ◽  
Low Voltage ◽  
X Ray ◽  
Voltage Electron

Electron microscopic and electron probe x-ray microanalysis (EPXMA) of prostatic intraluminal “crystalloids”

1992 ◽  
Vol 50 (1) ◽  
pp. 608-609
Author(s):  
H.X. Bui ◽  
A. delRosario ◽  
M. Abdulla ◽  
C.E. Sheehan ◽  
R.J. Emerson ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Light Microscopy ◽  
Electron Probe ◽  
Prostatic Adenocarcinoma ◽  
Electron Microscopic ◽  
X Ray ◽  
Significant Potential ◽  
Well Differentiated ◽  
Benign Prostate

Prostatic intraluminal “crystalloids” are intensely eosinophilic, non-birefringent crystalline-like structures readily identified with light microscopy. Well documented to be associated with prostatic adenocarcinoma, these rhomboidal, hexagonal, triangular, polyhedral, or needle-like structures are almost exclusively confined to well differentiated prostatic adenocarcinomas and may occasionally be seen in adjacent benign glands bordering the tumors. Although of significant potential as a signal of nearby cancer in a limited biopsy of benign prostate, these “crystalloids” are poorly defined and their chemical composition has not been determined.

MgCu4(SO4)2(OH)6 · 6H2O, the magnesium analogue of ktenasite from the Casualidad mine near Baños de Alhamilla, Almeria, Spain

2020 ◽  
Author(s):  
Jochen Schlüter ◽  
Thomas Malcherek ◽  
Boriana Mihailova ◽  
Christian Rewitzer ◽  
Rupert Hochleitner ◽  
...  
Keyword(s):  
Refractive Index ◽  
Chemical Composition ◽  
Electron Probe ◽  
New Mineral ◽  
Environmental Sciences ◽  
Unit Cell Parameters ◽  
Single Crystal Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Perfect Cleavage

The new mineral fehrite (IMA 2018-125a), MgCu4(SO4)2(OH)6 · 6H2O, is a member of the ktenasite group andthe Mg-analogue of ktenasite, ZnCu4(SO4)2(OH)6 · 6H2O. The mineral was found in the Casualidad mine near Baños deAlhamilla, Almeria, Spain, in association with clinoatacamite, kapellasite, gordaite, serpierite, connellite and gypsum.The transparent turquoise-coloured mineral has a vitreous lustre, exhibits a pale blue-green streak and shows distinctpleochroism. It forms radial aggregates of thin lath-like crystals of up to 200 μm in length. Fehrite is not fluorescent. Themonoclinic crystals show a perfect cleavage parallel to {001}. The mineral has a brittle tenacity and an uneven fracture. Thecalculated density is 2.73 g/cm3, the calculated mean refractive index is 1.584. The strongest lines observed in the X-raypowder diffraction pattern are [d in Å/Irel in %/(hkl)] 11.94/100/002, 5.92/31/004, 2.66/12/202, 4.85/11/013, 3.93/11/006and 2.96/10/008. The chemical composition, measured by means of an electron probe micro-analyser, was determined at(wt.%): MgO 5.31, MnO 0.49, CuO 33.12, ZnO 11.48, SO3 26.01, H2Ocalc. 24.63, total 101.04. The empirical formula basedon 20 O pfu., including 6(OH) and 6(H2O), is Mg0.87Cu2.74Zn0.93Mn0.05S2.14O8(OH)6 · 6H2O. The simplified end memberformula is MgCu4(SO4)2(OH)6 · 6H2O which requires MgO 5.92, CuO 46.74, SO3 23.52, H2O 23.82, total 100.00 (wt.%).Fehrite is monoclinic with space group P21/c (#14). Unit cell parameters determined by X-ray single crystal diffraction area = 5.6062(8), b = 6.1294(11), c = 23.834(3) Å, β = 95.29(1)º, V = 815.5(2) Å3, Z = 2. The mineral is isotypic with ktenasitewith Mg in place of Zn. The name is for the late Karl Thomas Fehr (1954 – 2014), Professor of Mineralogy at the Departmentof Geo- and Environmental Sciences at the Ludwig-Maximilians-University Munich, Germany.

Study on Gemological and Mineralogy Features of Huanglong Jade

2011 ◽  
Vol 492 ◽  
pp. 388-391
Author(s):  
Jun Zhao ◽  
En Dong Zu ◽  
Dong Ye ◽  
Nan Yu Shen
Keyword(s):  
Trace Elements ◽  
Refractive Index ◽  
Chemical Composition ◽  
Relative Density ◽  
Electron Probe ◽  
X Ray ◽  
Field Samples ◽  
Main Chemical Composition

The Huanglong jade of Zhen’an, Xiaoheishan, Supa river these three fields in Longling Yunnan were detected by general gem identify instruments. The Moh's hardness is 6.5-7, relative density is 2.60(+0.10, -0.05)g/cm3 and the refractive index is 1.53±. The electron probe backscatter atlas of samples shows that Huanglong jade is a kind of cryptocrystalline mineral aggregation. Using electron probe and X-ray spectrometer tested different field samples, got that the main chemical composition of Huanglong jade is SiO2, furthermore, including same trace elements as K, Cr, Fe, As and so on. Finally judged that Huanglong jade is a kind of cryptocrystalline (or micro show crystal) mineral aggregation which mainly formed of SiO2, named yellow chalcedony (Huanglong jade).

Improvements in the electron probe forming capabilities and x-ray hole counts in the Philips TEM

1983 ◽  
Vol 41 ◽  
pp. 376-377
Author(s):  
Richard L. McConville
Keyword(s):  
Field Strength ◽  
Electron Probe ◽  
Spherical Aberration ◽  
Focal Length ◽  
Objective Lens ◽  
Parallel Beam ◽  
Tilt Axis ◽  
X Ray ◽  
Small Probe ◽  
Specimen Height

A second generation twin lens has been developed. This symmetrical lens with a wider bore, yet superior values of chromatic and spherical aberration for a given focal length, retains both eucentric ± 60° tilt movement and 20°x ray detector take-off angle at 90° to the tilt axis. Adjust able tilt axis height, as well as specimen height, now ensures almost invariant objective lens strengths for both TEM (parallel beam conditions) and STEM or nano probe (focused small probe) modes.These modes are selected through use of an auxiliary lens situ ated above the objective. When this lens is on the specimen is illuminated with a parallel beam of electrons, and when it is off the specimen is illuminated with a focused probe of dimensions governed by the excitation of the condenser 1 lens. Thus TEM/STEM operation is controlled by a lens which is independent of the objective lens field strength.

Spatial resolution of X-ray microanalysis in thin foils

1978 ◽  
Vol 36 (1) ◽  
pp. 544-545
Author(s):  
R. Hutchings ◽  
I.P. Jones ◽  
M.H. Loretto ◽  
R.E. Smallman
Keyword(s):  
Spatial Resolution ◽  
Electron Probe ◽  
Beam Divergence ◽  
Inelastic Interaction ◽  
Specimen Thickness ◽  
High Current ◽  
Beam Spreading ◽  
X Ray ◽  
Thin Foils ◽  
Complex Calculation

There is increasing interest in X-ray microanalysis of thin specimens and the present paper attempts to define some of the factors which govern the spatial resolution of this type of microanalysis. One of these factors is the spreading of the electron probe as it is transmitted through the specimen. There will always be some beam-spreading with small electron probes, because of the inevitable beam divergence associated with small, high current probes; a lower limit to the spatial resolution is thus 2αst where 2αs is the beam divergence and t the specimen thickness.In addition there will of course be beam spreading caused by elastic and inelastic interaction between the electron beam and the specimen. The angle through which electrons are scattered by the various scattering processes can vary from zero to 180° and it is clearly a very complex calculation to determine the effective size of the beam as it propagates through the specimen.

High spatial resolution x-ray microanalysis of interfaces

1995 ◽  
Vol 53 ◽  
pp. 284-285
Author(s):  
J. R. Michael
Keyword(s):  
Spatial Resolution ◽  
Electron Probe ◽  
Solid Angle ◽  
Collection Efficiency ◽  
Spatial Scales ◽  
Energy Dispersive Spectrometer ◽  
X Rays ◽  
X Ray ◽  
Probe Size ◽  
Brightness Field

X-ray microanalysis in the analytical electron microscope (AEM) refers to a technique by which chemical composition can be determined on spatial scales of less than 10 nm. There are many factors that influence the quality of x-ray microanalysis. The minimum probe size with sufficient current for microanalysis that can be generated determines the ultimate spatial resolution of each individual microanalysis. However, it is also necessary to collect efficiently the x-rays generated. Modern high brightness field emission gun equipped AEMs can now generate probes that are less than 1 nm in diameter with high probe currents. Improving the x-ray collection solid angle of the solid state energy dispersive spectrometer (EDS) results in more efficient collection of x-ray generated by the interaction of the electron probe with the specimen, thus reducing the minimum detectability limit. The combination of decreased interaction volume due to smaller electron probe size and the increased collection efficiency due to larger solid angle of x-ray collection should enhance our ability to study interfacial segregation.

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