ISSN:0049-8246    

DOI:10.1002/xrs.1300020413

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

年代:1973

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300020414

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

年代:1973

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300020402

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

年代:1973

数据来源: WILEY

摘要:

AbstractOn the assumption that X‐ray count data are normally distributed, certain tests for detecting outliers or ‘wild’ values within replicate sets of three measurements are compared. Treated as ‘insurance policies’ rather than formal statistical tests, the statistics discussed are useful for monitoring X‐ray data, particularly in computer oriented systems. The problem of the correction of outliers is briefl

ISSN:0049-8246    

DOI:10.1002/xrs.1300020403

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

年代:1973

数据来源: WILEY

摘要:

AbstractThe conversion of X‐ray fluorescence intensities to concentrations by a mini‐computer requires simple equations for routine use. The influence coefficients, accounting for inter‐element effects in homogeneous samples, are calculated from fundamental parameters by means of a programme called ALPHAS operating on a large computer. These coefficients can subsequently be used in the simple routine equations for wide range calibration. The theoretical coefficients are a valuable support for wide range calibrations using multiple regression analysis. The number of required standards is significantly reduced. The exclusive use of theoretical influence coefficients is demonstrated for stainless

ISSN:0049-8246    

DOI:10.1002/xrs.1300020404

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

年代:1973

数据来源: WILEY

摘要:

AbstractThe ratio of the total characteristic to white radiation from a chromium target spectrographic X‐ray tube has been determined by a new method at operating voltages ranging from 10 to 50 kV. The ratio valuesKare referred to the portion of the continuous spectrum extended from the Duane and Hunt limit λoto 2.5 Å A conversion coefficient has been tabulated to consider the continuous spectrum extended from λ to any arbitrary wavelength up to 6 Å. The method can be conveniently applied to targets other than chromium. It is only required to perform a simple fluorescence intensity measurement with a standard spectrometer on a conveniently prepared s

ISSN:0049-8246    

DOI:10.1002/xrs.1300020405

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

年代:1973

数据来源: WILEY

摘要:

AbstractCarbon has been determined in sedimentary rock samples using a series of artificial standards. C Kœ line positions for elemental carbon and carbon combined as carbonate differ by 0.51º θ: using an OHM analysing crystal. A ratio of the intensities at the two line positions allows the proportions of combined and elemental carbon present in a sample to be estimated. This proportion is then used to obtain the correct calibration slope factor for the determination of total carbon in the samp

ISSN:0049-8246    

DOI:10.1002/xrs.1300020406

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

年代:1973

数据来源: WILEY

摘要:

AbstractThe energy difference between two overlapping X‐ray emission lines with Lorentzian shapes has been calculated as a function of the total line profile for several combinations of intensity ratio and half width ratio of the component lines. Natural line widths of Kα1and Kα2for neon to uranium are listed from available literature val

ISSN:0049-8246    

DOI:10.1002/xrs.1300020407

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

年代:1973

数据来源: WILEY

摘要:

AbstractThe instrument smearing function of a two‐crystal spectrometer in the (n, n) position having negligible vertical divergence has been calculated for an unpolarized incident beam assuming the crystals to be centro‐symmetric and to reflect according to the Prins‐Darwin theory. The results are given in terms of the parametersgand s̀ which describe the ‘overall absorption’ and the imaginary part of the structure factor, respectively. In the regiong, s̀ σ ≤ 0.5 asymmetries of up to 60% are found in the smearing function. Variations of several tens of per cent occur in the half‐breadth as compared with the breadth obtained for a σ polarized beam with no absorption.In order to avoid the undesirable effects of absorption, silicon (111) crystals should not be used above wavelengths 3 to 4 Å. Suitable wavelengths for calcite (211) crysta

ISSN:0049-8246    

DOI:10.1002/xrs.1300020408

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

年代:1973

数据来源: WILEY

摘要:

AbstractVarious ore fractions (and mixtures thereof), of which the main metallic components are iron, copper and zinc, were analysed by means of radioisotope X‐ray fluorescence spectroscopy using a Si(Li) detector. As a result existing equations which deal with interelement effects (selective attenuation and enhancement of characteristic radiation) were further developed, and a new set of general equations, which accounts for the important interelemental background contribution, has been formulated. Its validity has been experimentally tested over a wide range of concentrations which, in some cases, varied by as much as a factor of 200. Satisfactory results were obtaine

ISSN:0049-8246    

DOI:10.1002/xrs.1300020409

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

年代:1973

数据来源: WILEY