ISSN:0049-8246    

DOI:10.1002/xrs.1300110402

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe Compton scattering technique for rapid determination of ash content in coal has been extended to coke samples. Some improvements in respect of the sample preparation and possible line overlap and background have been incorporated. A modified regression equation used in this work to compute the x‐ray data is found to yield good result

ISSN:0049-8246    

DOI:10.1002/xrs.1300110403

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

年代:1982

数据来源: WILEY

摘要:

AbstractX‐ray fluorescence analyses of briquetted rock samples for S, Cl and F were carried out utilizing experimental coefficients to correct matrix effects. Data on thirty‐two international standards are repor

ISSN:0049-8246    

DOI:10.1002/xrs.1300110404

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

年代:1982

数据来源: WILEY

摘要:

AbstractA new type of a formed filter paper is proposed as a sample medium for a microdroplet analysis by x‐ray fluorescence spectrometry. It has a circular center part, separated by a narrow circular groove from its edge, and four, paraffined, supporting bridges. It can thus keep a spot area constant when a liquid sample drops at the center part. After dropping the liquid sample, the paper is dried and used for the x‐ray measurement. It can be stored for years without any chemical change. This formed filter paper is effective in improving the linearity range of a calibration curve and the precision of a fluorescent x‐ray measurement as compared with a non‐formed filter paper. The sample volume required is only 20 to 100 μ1 and therefore microscale analysis of the liquid sample is a

ISSN:0049-8246    

DOI:10.1002/xrs.1300110405

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe L11and L111absorption discontinuities of Tb in various Tb compounds have been recorded using an automated and highly stable x‐ray unit. The energy shifts have been discussed in terms of effective ionic charge. Applying Levy's method, the radii of the first coordination sphere have been calculated from the extended fine structur

ISSN:0049-8246    

DOI:10.1002/xrs.1300110406

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

年代:1982

数据来源: WILEY

摘要:

AbstractFundamental parameter interelement correction methods such as NRLXF are finding increased use in quantitative x‐ray spectrometry. The purpose of this work was to compare the results obtained with each of the three options in NRLXRF, namely empirical, full, and theoretical, with a semiempirical model such as Rasberry‐Heinrich and an NBS fundamental parameter method to check for consistency. Well characterized alloys were chosen for making the intercompari

ISSN:0049-8246    

DOI:10.1002/xrs.1300110407

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

年代:1982

数据来源: WILEY

摘要:

AbstractAn overview of a fundamental parameter, data reduction procedure for processing energy‐dispersive, x‐ray spectrometric data obtained with monochromatic excitation is described. The programs, calledEXFNBSandNBSROI, are written inFORTRANand correct for interfering x‐ray peaks, escape peaks, background, and x‐ray absorption/enhancement due to interelement effects in a speciment. This procedure is designed to operate in an interactive mode with a minicomputer in re

ISSN:0049-8246    

DOI:10.1002/xrs.1300110408

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

年代:1982

数据来源: WILEY

摘要:

AbstractA Monte Carlo model is derived and combined with an existing detector response function model to ptdict the entire pulse‐height spectra for energy‐dispersive, x‐ray fluorescence systems that consist of an annular‐ring, photon exciting source, a coaxially positioned right circular homogental sample, and a cirular si(Li) detector. A method is dervied and demonstrated for using the predicted and experimental pulse‐height spectra on a chi‐square basis to determine elemental amounts. This approach allows the use of all the information available in an entire energy‐dispersive, x‐ray fluorescence pulse‐hight spectrum for

ISSN:0049-8246    

DOI:10.1002/xrs.1300110409

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe Monte Carlo model for predicting the complete spectral response from homogeneous samples has been extended to heterogeneous samples which may be considered to be spherical particles suspended in a homogeneous matrix. The spherical particles may have any distribution of size and spatial position as specified input. The particle compositions are either: Model 1‐a homogeneous mixture of all the sample elements present or Model 2‐a single pure element appropriately chosen at random from those present. These two sample compositions should represent extremes of the matrix interferences encountered in practice and should, therefore, bound the x‐ray and source scattering spectral responses observed. The sample Monte Carlo results reported here for both heterogeneous models approach the limiting values predicted by the homogeneous model when used for decreasingly small particle sizes and generally exhibit a smooth relationship with particle size. Although comparisons with two sets of experimental results are not entirely satisfactory, the general trends are properly predicted. It is concluded that the models are accurate within our present capability of testing them (at present we only have available two particle spatial distributions for packing fractions of 0.4 and 0.6, both for particles of uniform

ISSN:0049-8246    

DOI:10.1002/xrs.1300110410

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe Gaussian expression for ϕ(ρz) has been used as the basis of a computer program for quantitative electron probe microanalysis. Corrections for absorption and atomic number are combined within the expression for ϕ(ρz) whereas the fluorescence correction is based on numerical integration over the primary and secondary intensities. Error histograms based on about 500 published analyses of standard specimens have been used to adjust the parameters in the Gaussian expression for optimum accuracy. The resultant error histograms are as narrow as those obtained for the most accurate of the current ZAF correction procedures. Extension of the method to non‐normal electron incidence is relatively straightfo

ISSN:0049-8246    

DOI:10.1002/xrs.1300110411

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

年代:1982

数据来源: WILEY