ISSN:0049-8246    

DOI:10.1002/xrs.1300070202

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

年代:1978

数据来源: WILEY

摘要:

AbstractThirty analyses of each of nine well‐characterized silicate glasses and minerals have been made, using a Link Systems Model 290‐2KX energy‐dispersive spectrometer, fitted to a Cambridge Geoscan. Statistical analysis of the analytical data shows that the accuracy and precision of energy‐dispersive analyses are comparable to wavelength‐dispersive analyses, provided that more than about 1 wt% of each element of interest is present. The detection limits for different elements vary accrding to the nature of the sample, the element concerned and the counting time. For 100 liveseconds counting times the detection limits are in the range from 0.05–0.26 wt %

ISSN:0049-8246    

DOI:10.1002/xrs.1300070203

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

年代:1978

数据来源: WILEY

摘要:

AbstractA Siemens SRS X‐ray spectrometer, with 10 sample chamber has been interfaced to a PDP11/10 mini‐computer through a CAMAC interface. Digital Equipment Corporation's RT11 operating system is used to support the Fortran programs which run the instrument. Advantages of this arrangement are: (1) The CAMAC modular interface philosophy makes simple any hardware re‐arrangements and extension to other instrument; (2) High level language programs are easily written for instrument control, data collection and processing; and (3) Simple English language dialogue via an inexpensive television console makes operation possible by all levels of pers

ISSN:0049-8246    

DOI:10.1002/xrs.1300070204

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

年代:1978

数据来源: WILEY

摘要:

AbstractThe analysis of energy‐dispersive X‐ray spectra in the low energy region is complicated by the fact that the shape of the background curve is distorted by absorption and the characteristic peaks partially overlap. A computer program (FORTRAN) has been developed, which fits to the measured spectrum an artificially generated one, composed of calculated background and peaks. The parameters defining the artificial spectrum are simultaneously adapted. After four to five iterations of that adaptation, good agreement with the measured spectrum is achieved. This procedure takes about 3 min, using a small computer sys

ISSN:0049-8246    

DOI:10.1002/xrs.1300070205

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

年代:1978

数据来源: WILEY

摘要:

AbstractA new energy‐dispersive X‐ray technique has been developed for rapid quantitative analysis in the scanning electron microscope. The relative sensitivity is first established for as many elements as can be obtained in pure solid form. These values need only be measured once for a given accelerating potential and X‐ray take‐off angle. Relative sensitivities for elements not measured may be obtained by interpolation. Quantitative analysis may then be made by dividing the relative characteristic intensity for each element present by its respective elemental sensitivity. The ratios are subsequently adjusted by means of an iterative technique, using one of the commonly used electron microprobe matrix correction methods, until a set of concentrations which total 100% is obtained. The technique offers the advantages that neither the electron beam current nor the counting time enter into the calculations. Therefore, arbitrary counting times and unstable electron beam currents may be used. It is not necessary for standards to be continually analyzed; a single spectrum combined with the original sensitivity data contain all the information required for the a

ISSN:0049-8246    

DOI:10.1002/xrs.1300070206

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

年代:1978

数据来源: WILEY

摘要:

AbstractEnergy‐dispersive X‐ray fluorescence analysis (XES) using secondary fluorescers of Ti and Mo is compared with particle‐induced X‐ray emission analysis (PIXE) using protons of 2.3 MeV and 5.0 MeV for the analysis of air particulate matter. Experimental detection limits are derived from the analysis of an impactor sample collected on Whatman‐41, Millipore AAWP, and 0.4 μm Nuclepore filters and from the analysis of an impactor sample on a Mylar foil from stage 4 in a 5‐stage single orifice cascade impactor. The detection limits are compared using the criterion of equal number of counts in the spectra. PIXE is shown to give about three times lower detection limits for the filter samples and about 30 times lower limits for the impactor sample. The conclusions to be drawn from this and other aspects on the difference between XES and PIXE in the analysis of aerosol samples are thoroughly discussed and the results are extrapolated to the analysis of other environme

ISSN:0049-8246    

DOI:10.1002/xrs.1300070207

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

年代:1978

数据来源: WILEY

摘要:

AbstractBackground calculations for low‐energy energy‐dispersive X‐ray spectra from biological ice, when attempting quantitative microanalysis, must take into account the anomalous gold MIV, Vabsorption edges at 2220 and 2307 eV. The discrepancy between the mass absorption coefficient from generalized tables used in the electron microprobe analysis and those values actually observed is pointed out. The spectral shape of the Au MIV, Vedges is discussed in terms of the photoionization cross‐section of the 3d‐subshell. Theoretical and experimental results are comparted with the table values. A formula used in the calculation of spectrometer efficiency and spectral background

ISSN:0049-8246    

DOI:10.1002/xrs.1300070208

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

年代:1978

数据来源: WILEY

摘要:

AbstractA modified Lanchance–Trail approach is presented for the empirical determination of XRF interelement correction coefficients through experimentation. An exhaustive study of binary systems involving aqueous solution media has been used to obtain the true effects of one element on another, with the additional possibility of taking into consideration other effects which become apparent, such as enhancement effects. The method is described in detail, with several examples provided to show the effectiveness of the procedure. A total of approximately 200 coefficients have been investigated and are discusse

ISSN:0049-8246    

DOI:10.1002/xrs.1300070209

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

年代:1978

数据来源: WILEY

摘要:

AbstractPublished investigations of the energy‐dispersive microprobe analysis of stainless steel repeated using the Reed/Fiori method of calculating the background intensity distribution. It is shown that the ‘interference effect’ in Kβ/Kα intensity ratios for elements in steels, which arose from studies using the Fourier transformation and frequency filtered background subtraction method, is due to deficiencies in this method. The systematically negative errors in analyses of Ni in steel are studied and can be corrected by using the Reed/Fiori

ISSN:0049-8246    

DOI:10.1002/xrs.1300070210

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

年代:1978

数据来源: WILEY

ISSN:0049-8246    

DOI:10.1002/xrs.1300070211

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

年代:1978

数据来源: WILEY