ISSN:0049-8246    

DOI:10.1002/xrs.1300190302

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

年代:1990

数据来源: WILEY

摘要:

AbstractAn absolute method for the determination of the thickness of a metal film deposited on a metallic substrate is described. The method is based on the measurement of fluorescent intensity ratios for two lines from the substrate element. Titanium sheets covered with nickel layers of different thicknesses (between 3 and 22 μm) were employed to test the method. Intensity measurements were performed using different excitation modes and detection systems. Additionally, the proposed method can be employed to determine the density of the deposited material or the incident angle of primary radiation and take‐off angle if the deposited metal film thickness is known. The method can be applied by using the intensity ratios of two lines generated through electron vacancies in the same she

ISSN:0049-8246    

DOI:10.1002/xrs.1300190303

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

年代:1990

数据来源: WILEY

摘要:

AbstractProcedures are presented for reducing the complexity of common energy‐dispersive x‐ray emission spectra. The methods are two rapid and simple spectra‐processing tools that eliminate, channel by channel, both the escape effect and all Kβ lines coupled to the corresponding Kα lines. An outline of problems related to the escape‐effect correction and Kβ line stripping is given. Listings of programs in Turbo‐Pascal a

ISSN:0049-8246    

DOI:10.1002/xrs.1300190304

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

年代:1990

数据来源: WILEY

摘要:

AbstractX‐ray emission spectroscopy was used to establish the valency of Cu in the superconducting (La1‐xBax)2CuO4±y(LBCO) system. Samples were prepared by both solid‐state diffusion and coprecipitation methods. It was observed that diffusion is faster and mixing is more intimate in the coprecipitated sample. A definite shift in the Cu K emission was also observed in samples such as CuO, La2CuO4and LBCO. It was observed that the valency of copper in the LBCO system is equal to or greater than 2. Further, Ba has been found to play a major role in the emission process. The La emission spectra remained the same for all the samples studied. SEM and XRD studies indicated the presence of a two‐phase structure of the

ISSN:0049-8246    

DOI:10.1002/xrs.1300190305

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

年代:1990

数据来源: WILEY

摘要:

AbstractUsing a data library of element‐specific x‐ray energies and their relative intensities in PIXE, a computer code named MAXE (material analysis by x‐ray emission) was written for spectrum deconvolution and inspection. Subroutines were included for peak identification, background continuum generation, system calibration, peak deconvolution and peak‐area determination. The background is fitted in parts by an exponential function which allows excellent background generation for any matrix. In addition, combined data collection from the RBS and PIXE set‐ups in the same chamber is possible thoough the code. This allows for double checking of the elemental composition and a wide coverage of the elements that are present in the sample matrix. A performance test of our code compared with a widely used program (AXIL) for PIXE analysis showed good

ISSN:0049-8246    

DOI:10.1002/xrs.1300190306

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

年代:1990

数据来源: WILEY

摘要:

AbstractThe reliable, routine XRF determination of trace elements in iron‐rich geological samples, such as banded iron formations, oolitic ironstones and ferromanganese nodules, has until recently been limited. The scattered radiation method (using Compton scattering), well established in normal silicate rock analysis, was developed for the determination of trace element concentrations in diverse rock compositions. Single calibration lines are used for each trace element and serve to provide data over broad sample compositions, ranging from 0 to 70% Fe2O3. A critical evaluation of the calibration lines obtained and the results of trace analyses of synthetic mixtures showed the method to be readily capable of providing accurate chemical dat

ISSN:0049-8246    

DOI:10.1002/xrs.1300190307

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

年代:1990

数据来源: WILEY

摘要:

AbstractAl and Zn coordination states in several kinds of glasses were measured with a common x‐ray fluorescence spectrometer. The results showed that the Al in P2O5‐Na2O‐BaO‐Al2O3phosphate glass is all sixfold coordinated, the Al in alkaline silicate glass is fourfold coordinated and the Zn in Na2O‐ZnO‐B2O3glass system is all fourfold coordinated, the results being in agreement with those given by EXAFS. It is concluded that the study of the coordination states of complex glass systems is an effec

ISSN:0049-8246    

DOI:10.1002/xrs.1300190308

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

年代:1990

数据来源: WILEY

摘要:

AbstractA comparison of estimated performance of x‐ray spectrometers employing Cauchouis and DuMond arrangements shows that the latter are 5‐15 times more efficient at the same resolution. These data and the experimental performances of the above spectrometers and of the Soller type in the U Lα1region with standard granite specimens suggest that it is advisable to develop short‐wavelength analytical spectrometers with the DuMond arran

ISSN:0049-8246    

DOI:10.1002/xrs.1300190309

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

年代:1990

数据来源: WILEY

摘要:

AbstractA previously described method for correction of PIXE data based on the measurement of proton energy loss, ΔE, and x‐ray transmission factors has been tested on international geological, biological and ore reference materials. After a short review of the sample preparation method and the experimental procedures, the analytical results, precision and accuracy are discuss

ISSN:0049-8246    

DOI:10.1002/xrs.1300190310

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

年代:1990

数据来源: WILEY

摘要:

AbstractA study of the suitability of the Tertian algorithm using new ‘accurate’ binary influence coefficients and a comparison standard for x‐ray fluorescence analysis of geological materials prepared as borax glass beads was performed. The algorithm was found to give satisfactory results for the analysis of four major components in geological materials. Even in the worst case, when there is a factor of 20 difference in the concentration in the specimen and a comparison standard, the algorithm gives results which differ from the true results by a factor of about 2. This makes the algorithm attractive as a diagnostic tool in analyses of unknown specimens and in the identification of appropriate standards. The binary coefficients are easily calculated so that the algorithm can be implemented on a minicom

ISSN:0049-8246    

DOI:10.1002/xrs.1300190311

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

年代:1990

数据来源: WILEY