Total reflection X-ray fluorescence analysis of trace-elements in candies marketed in Mexico

Abstract The distribution of trace elements Fe, Cu, Zn, Se, and Rb was determined in sera from patients with the complete type of Behçet disease in the active stage and from healthy controls. Total reflection x-ray fluorescence was used for quantitative analysis; in general, atomic absorption spectrometry was used only for control of the Se values. Zn, Se, and Rb concentrations were significantly (P < 0.0001) lower for patients than for control subjects. No significant difference was determined in the Fe content. However, there was a significant increase in Cu in the patients so that the ratios Cu/Zn, Cu/Se, and Cu/Rb were significantly higher for the patients than for the control subjects (P < 0.0001).

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XRMF applications of a monolithic, polycapillary, focusing x-ray optic

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163666 ◽

1996 ◽

Vol 54 ◽

pp. 240-241

Author(s):

D. A. Carpenter ◽

Ning Gao ◽

G. J. Havrilla

Keyword(s):

Trace Elements ◽

Point Source ◽

Focal Spot ◽

Fluorescence Analysis ◽

X Rays ◽

Focal Distance ◽

Spot Diameter ◽

X Ray ◽

Focal Spot Diameter

A monolithic, polycapillary, x-ray optic was adapted to a laboratory-based x-ray microprobe to evaluate the potential of the optic for x-ray micro fluorescence analysis. The polycapillary was capable of collecting x-rays over a 6 degree angle from a point source and focusing them to a spot approximately 40 µm diameter. The high intensities expected from this capillary should be useful for determining and mapping minor to trace elements in materials. Fig. 1 shows a sketch of the capillary with important dimensions.The microprobe had previously been used with straight and with tapered monocapillaries. Alignment of the monocapillaries with the focal spot was accomplished by electromagnetically scanning the focal spot over the beveled anode. With the polycapillary it was also necessary to manually adjust the distance between the focal spot and the polycapillary.The focal distance and focal spot diameter of the polycapillary were determined from a series of edge scans.

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Control of trace elements content in solid-phase extraction sorbent by x-ray fluorescence analysis

10.1063/5.0032672 ◽

2020 ◽

Author(s):

E. V. Kochergina ◽

A. O. Vagina ◽

A. O. Taukin ◽

A. V. Abramov ◽

G. M. Bunkov ◽

...

Keyword(s):

Trace Elements ◽

Solid Phase Extraction ◽

Solid Phase ◽

Fluorescence Analysis ◽

Phase Extraction ◽

X Ray

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How to Use the Features of Total Reflection of X-Rays for Energy Dispersive XRF

Advances in X-ray Analysis ◽

10.1154/s037603080002036x ◽

1988 ◽

Vol 32 ◽

pp. 105-114 ◽

Cited By ~ 2

Author(s):

H. Schwenke ◽

W. Berneike ◽

J. Knoth ◽

U. Weisbrod

Keyword(s):

Thin Films ◽

Penetration Depth ◽

Fluorescence Analysis ◽

Total Reflection ◽

X Rays ◽

X Ray ◽

Characteristic Features ◽

Respective Characteristic ◽

Nanometer Regime ◽

Sensitive Method

AbstractThe total reflection of X-rays is mainly determined by three parameters , that is the orltical angle, the reflectivity and the penetration depth. For X-ray fluorescence analysis the respective characteristic features can be exploited in two rather different fields of application. In the analysis of trace elements in samples placed as thin films on optical flats, detection limits as low as 2 pg or 0.05 ppb, respectively, have been obtained. In addition, a penetration depth in the nanometer regime renders Total Reflection XRF an inherently sensitive method for the elemental analysis of surfaces. This paper outlines the main physical and constructional parameters for instrumental design and quantitation in both branches of TXRF.

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