Cu<i>K</i>α<sub>2</sub>elimination algorithm

The unique among pyrometallurgical slags, coarsegrained (up to 2.5 cm) segregations (up to 40 cm long) rimmed by Baplitic^border zones occur within holocrystalline historical Zn-smelting slag in Katowice, S Poland. Slag surrounding the segregations consists of olivine, spinel series, melilite, clinopyroxene, leucite, nepheline and sulphides. Ca-olivines, kalsilite and mica compositionally similar to oxykinoshitalite occur in border zones in addition to olivine, spinel series and melilite. Miarolitic and massive pegmatite-like segregations are built of subhedral crystals of melilite, leucite, spinel series, clinopyroxene and hematite. Melilite, clinopyroxenes and spinels in the segregations are enriched in Zn relatively to original slag and to fine-grained border zones. The segregations originated as a result of crystallization from residual melt rich in volatiles (presumably CO 2 ). The volatilerich melt was separated during fractional crystallization of molten slag under the cover of the overlying hot (ca. 1250°C) vesicular slag, preventing the escape of volatiles. That unique slag system is analogous to natural magmatic systems.

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“…The X'PERT HighScore Plus software was applied for data processing. The elimination algorithm of Ladell et al (1975) was used for Kα2 stripping.…”

Section: Methodsmentioning

confidence: 99%

Mineralogy and origin of coarse-grained segregations in the pyrometallurgical Zn-Pb slags from Katowice-Wełnowiec (Poland)

et al. 2016

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“…zl,~/,~ = 0.000306, the value given by Ladell, Zagofsky & Pearlman (1975) indicates that, for the relevant Bragg-angle region, the two expressions yield identical results.…”

Section: = Arcsin [(A + Aa/2)/(2dh)]mentioning

confidence: 91%

The half-widths of powder Bragg intensity profiles deduced in reciprocal space. I. Ideal powders

Rossmanith¹

1994

Acta Cryst Sect A

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New formulas for the full widths at half-maxima (FWHMs) of powder Bragg intensity profiles are deduced in reciprocal space, using the concept for the calculation of the peak width introduced for single-crystal diffractometry by Rossmanith [Acta Cryst. (1992), A48, 596-610]. In paper I, a basic formula for strain-free and prefer.red-orientation-free powders is deduced. Furthermore, it is shown that comparison of experimental widths with theoretical FWHMs calculated with the new expression results in physically significant values for the particle size in the powder. In a forthcoming paper II, the effect of strain on the FWHM will be analysed. IntroductionProfile analysis of powder diffraction diagrams requires knowledge of the height, width and distribution function (i.e. Gauss, Lorentz, pseudo-Voigt etc.) of the intensity profile.© 1994 International Union of Crystallography Printed in Great Britain -all rights reserved Expressions for the calculation of the resolution functions of N-crystal powder spectrometers are given by, for example, Sabine (1987) and Wroblewski (1991). The formulas given by these authors are difficult to handle for two reasons. First, most of the transmission and reflection probability distributions involved in the expressions are not known exactly in routine powder diffraction experiments. Second, evaluation of these expressions requires timeconsuming computations of integrals, even if approximations (for example pseudo-Voigt) for the distribution functions are used.The widths of the Bragg intensity profiles are, therefore, usually calculated using the simplified version of the formula given by Caglioti, Paoletti & Ricci (1958):A202 --U tan 2 0 + V tan 0 + W.(1 a)In Rietveld analysis (Rietveld, 1969), the physically meaningless half-width parameters U, V and W are determined by least-squares fitting of calculated to measured FWHMs.A cta Crystallographica Section A ISSN 0108-7673 ©1994 HALF-WIDTHS OF POWDER BRAGG INTENSITY PROFILES. IRossmanith (1992) introduced a new concept for the calculation of the widths of Bragg intensity profiles for single and multiple diffraction in single-crystal diffractometry. In this paper and in Rossmanith (1993a), it is shown that, with representation of the half-width parameters AA/A (wavelength spread), ~ (divergence), r (mosaic-block radius) and r/ (mosaic spread) as well as the experimental conditions of the diffraction in reciprocal space, the widths of the profiles for single and multiple diffraction can be obtained from purely geometrical considerations. In Rossmanith (1993b), the simple but very effective approximation AOh = +--~ + (AA/A) tan Oh + 2A/(r sin 20h) + ~7 = 6[ --+ 1 + (tan 0h/tan 0M)] + 2A/(r sin 20h) + ~7 (lb) was derived for the width A0 h of the Bragg intensity profile measured with a triple-crystal diffractometer at a synchrotron-radiation source in parallel (-) and antiparallel (+) arrangements of the crystal with respect to the monochromator. Oh and 0M are the kinematical Bragg angles of the sample and monochromator, re...

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“…Les r6sultats sont alors comparables 5. ceux obtenus par Mortier & Costenoble (1973), ces auteurs utilisant le d6veloppe-ment en s6rie de Fourier de la fonction I(x) exp6ri-mentale. Ladell, Zagofsky & Pearlman (1975) pr6-sentent un algorithme permettant l'61imination de K~2. Cependant les r6sultats de ces auteurs sont meilleurs pour les positions des raies que pour la forme des raies reconstitu6es.…”

Section: Contr6le Des R~sultats Diverses Caract6ristiquesunclassified

Application du lissage des raies de diffraction des rayons X à la séparation du doubletKα₁Kα₂

Mignot¹,

Rondot²

1976

J Appl Cryst

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It may be very useful to know a mathematical expression which helps reconstruct the X-ray diffraction profile. It is in fact easier to work on one relation I(0)=f(0) rather than on a series of experimental points.The relation proposed in this paper,gives a good correspondence between experimental values and the values calculated in the case of a monochromatic source. Its use still remains very simple in the case of a doublet, K~I K~2, which can be expressed as follows:Ir, l(x) is given by the previous expression, A represents the angular separation of the doublet. Different forms of profiles are used in order to verify the validity of the relation proposed and the results are compared with those resulting from the Rachinger classical method.

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CuKα₂elimination algorithm

Cited by 77 publications

References 9 publications

Mineralogy and origin of coarse-grained segregations in the pyrometallurgical Zn-Pb slags from Katowice-Wełnowiec (Poland)

Mineralogy and origin of coarse-grained segregations in the pyrometallurgical Zn-Pb slags from Katowice-Wełnowiec (Poland)

The half-widths of powder Bragg intensity profiles deduced in reciprocal space. I. Ideal powders

Application du lissage des raies de diffraction des rayons X à la séparation du doubletKα₁Kα₂

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CuKα2elimination algorithm

Cited by 77 publications

References 9 publications

Mineralogy and origin of coarse-grained segregations in the pyrometallurgical Zn-Pb slags from Katowice-Wełnowiec (Poland)

Mineralogy and origin of coarse-grained segregations in the pyrometallurgical Zn-Pb slags from Katowice-Wełnowiec (Poland)

The half-widths of powder Bragg intensity profiles deduced in reciprocal space. I. Ideal powders

Application du lissage des raies de diffraction des rayons X à la séparation du doubletKα1Kα2

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CuKα₂elimination algorithm

Application du lissage des raies de diffraction des rayons X à la séparation du doubletKα₁Kα₂