X-Ray Cross-Sections in Design and Analysis of Non-Dispersive Systems

Advances in X-ray Analysis ◽

10.1154/s0376030800005322 ◽

1973 ◽

Vol 17 ◽

pp. 258-268

Author(s):

Benton C. Clark

Keyword(s):

Cross Sections ◽

Elemental Analysis ◽

Proportional Counter ◽

Theoretical Framework ◽

Energy Dispersive ◽

Fundamental Physics ◽

X Ray ◽

Element Concentrations ◽

Instrument Response ◽

Fluorescence Spectrometer

AbstractIn designing a radioisotope, energy-dispersive (proportional counter) x-ray fluorescence spectrometer for elemental analysis of geologic specimens, a theoretical framework has been developed to model instrument response. This model is based upon the fundamental physics of x-ray excitation, absorption, and scattering, and employs the most modern available values of the applicable physical constants. The model includes matrix absorption and enhancement effects. By explicitly including scattering in the model and the measurements, element concentrations can be calculated from the shape alone of the x-ray spectrum and the presence of elements having non-observable fluorescences can be detected.

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Preparation And elemental analysis of ancient fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126846 ◽

1987 ◽

Vol 45 ◽

pp. 410-411

Author(s):

Allen Angel ◽

Kathryn A. Jakes

Keyword(s):

Cross Sections ◽

Physical Structure ◽

Energy Dispersive ◽

Archaeological Sites ◽

X Ray ◽

Long Term Storage ◽

Backscattered Electron ◽

Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

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Field-Emission Scanning Electron Microscopy and Energy-Dispersive X-Ray Analysis to Understand the Role of Tannin-Based Dyes in the Degradation of Historical Wool Textiles

Microscopy and Microanalysis ◽

10.1017/s1431927614012793 ◽

2014 ◽

Vol 20 (5) ◽

pp. 1534-1543 ◽

Cited By ~ 10

Author(s):

Annalaura Restivo ◽

Ilaria Degano ◽

Erika Ribechini ◽

Josefina Pérez-Arantegui ◽

Maria Perla Colombini

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Elemental Composition ◽

Field Emission ◽

Cross Sections ◽

Morphological Changes ◽

Energy Dispersive ◽

X Ray ◽

Edx Analysis ◽

Scanning Electron

Abstract:An innovative approach, combining field-emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy (EDX) analysis, is presented to investigate the degradation mechanisms affecting tannin-dyed wool. In fact, tannin-dyed textiles are more sensitive to degradation then those dyed with other dyestuffs, even in the same conservation conditions.FESEM-EDX was first used to study a set of 48 wool specimens (artificially aged) dyed with several raw materials and mordants, and prepared according to historical dyeing recipes. EDX analysis was performed on the surface of wool threads and on their cross-sections. In addition, in order to validate the model formulated by the analysis of reference materials, several samples collected from historical and archaeological textiles were subjected to FESEM-EDX analysis.FESEM-EDX investigations enabled us to reveal the correlation between elemental composition and morphological changes. In addition, aging processes were clarified by studying changes in the elemental composition of wool from the protective cuticle to the fiber core in cross-sections. Morphological and elemental analysis of wool specimens and of archaeological and historical textiles showed that the presence of tannins increases wool damage, primarily by causing a sulfur decrease and fiber oxidation.

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