ISSN:0049-8246    

DOI:10.1002/xrs.1300230302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractA method is proposed for the quantitative elemental analysis of small inclusions in matrices with similar composition. The method is applicable provided that the difference between the matrix and the inclusion is at least one x‐ray‐detectable element. The approach is based on a technique for the determination of phase fractions by scanning the surface of the sample by the electron beam and recording the x‐ray intensities with an energy‐dispersive x‐ray spectrometer. By using the phase fraction of the matrix as a multiplier–coefficient, the contribution of the matrix to the overall area‐scanned spectrum around the inclusion is determined. Then the contribution of the matrix in the same spectrum is subtracted from the overall area‐scanned spectrum. The elemental composition of the remaining spectrum is analysed by the standardless ZAF method. The new method was tested experimentally with different sulphide inclusions within su

ISSN:0049-8246    

DOI:10.1002/xrs.1300230303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractProblems in the development and application of software for processing of environmental energy‐dispersive x‐ray fluorescence spectra of thin samples are reviewed. The main principles and requirements for the software are discussed. A new program, EXFIT‐8.10, was created to meet these requirements and is described in detail. It is capable of analyzing up to 50 elements simultaneously by combining results from up to 3 different excitation conditions. A set of supporting and post‐processing programs is also included. The main specifications of the software and possible ways for improvement are di

ISSN:0049-8246    

DOI:10.1002/xrs.1300230304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractSurface transformations of micro‐granules of a calcium‐phosphate glass (a bio‐glass) were examined by back‐scattered electron (BS) imaging and quantitative x‐ray energy‐dispersive spectroscopy (EDS) in a scanning electron microscope (SEM). All the images were obtained by using a backscattered electron detector of high efficiency and atomic numberZresolution (ΔZ= 0.3). The chemical transformations were induced duringin vivoimplantation of the bio‐glass in rabbit dorsal muscle sites. The observations showed the presence of an interlayered structure with different BS signal contrast. Quantitative EDS microanalysis performed by profiling the electron beam across the samples indicated the presence of hydrated calcium‐phosphate in the external layer, an inhomogeneous silica‐rich gel‐type layer in the mid‐layer and unaffected original Ca–P glass in the centre. A simple model, based on the balance of the concentrations of the elements (which have diffused) in the different layers, is proposed to explain the contribution of the elements constituting the original glass to the formation of the different layers. This result agrees with the experimental data obtained from image analysis. The microstructural behaviour of this type

ISSN:0049-8246    

DOI:10.1002/xrs.1300230305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractSingular perturbation methods were used to investigate the kinetic equation for electron distribution in targets. This approach permits the determination of the domains of applicability of kinetic equation approximations and the establishment of the connections between them. The analytical solution of the approximate kinetic equation in some of these domains was obtained and numerical calculations were performed in the others. On the basis of these solutions, the energy spectrum of backscattered electrons and the x‐ray depth distribution were foun

ISSN:0049-8246    

DOI:10.1002/xrs.1300230306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractA Si particle size effect was identified in the x‐ray fluorescence analysis of pitch, and is explained and quantified. Theoretical calculations were carried out to model the Si Kα intensity change with the SiO2particle size. The effective thickness of the analytical layer, the inter‐element effect (using theoretical alpha coefficients) and the sensitivity and lower limit of detection were calculated for the analytes in pitch using a Philips PW 1400 spectrom

ISSN:0049-8246    

DOI:10.1002/xrs.1300230307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractThis work indicates that counter ion distant neighbours affect the x‐ray absorption discontinuity. Cobalt(III) complexes of ethylenediamine containing different counter ions were used as models for this purpose. The results should provide useful information regarding the influence of counter ion distant neighbours on x‐ray absorption spec

ISSN:0049-8246    

DOI:10.1002/xrs.1300230308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractA Monte Carlo program to simulate the scattering contributions to the x‐ray fluorescent line was developed. Simulations were carried out on three pure samples (Z= 14, 28 and 40) in several geometrical situations (incident and take‐off directions of the photons). The results show that the scattering effects do not exceed 4% for the analysed elements in the X‐ray regime. Good agreement between normal incidence simulations and theoretical results was found. The vanishing of second‐order interactions inside the sample when the propagation plane approximates π/2 was also

ISSN:0049-8246    

DOI:10.1002/xrs.1300230309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300230310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300230311

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY