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Publié le 10 mars 2023

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1

Newbury, Dale E. « Standardless Quantitative Electron-Excited X-ray Microanalysis by Energy-Dispersive Spectrometry : What Is Its Proper Role ? » Microscopy and Microanalysis 4, no 6 (décembre 1998) : 585–97. http://dx.doi.org/10.1017/s1431927698980564.

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Electron beam X-ray microanalysis with semiconductor energy-dispersive spectrometry (EDS) performed with standards and calculated matrix corrections can yield quantitative results with a distribution such that 95% of analyses fall within ±5% relative for major and minor constituents. Standardless methods substitute calculations for the standard intensities, based either on physical models of X-ray generation and propagation (first principles) or on mathematical fits to remotely measured standards (fitted standards). Error distributions have been measured for three different standardless analysis procedures with a suite of microanalysis standards including metal alloys, glasses, minerals, ceramics, and stoichiometric compounds. For the first-principles standardless procedure, the error distribution placed 95% of analyses within ±50% relative, whereas for two commercial fitted standards procedures, the error distributions placed 95% of analyses within ±25% relative. The implication of these error distributions for the accuracy of analytical results is considered, and recommendations for the use of standardless analysis are given.
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2

Mandal, A. C., S. Santra, D. Mitra, M. Sarkar et D. Bhattacharya. « Bremsstrahlung excited standardless EDXRF analysis ». Nuclear Instruments and Methods in Physics Research Section B : Beam Interactions with Materials and Atoms 217, no 1 (mars 2004) : 104–12. http://dx.doi.org/10.1016/j.nimb.2003.09.030.

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3

pouchou, Jean-Louis, et Françoise Pichoir. « Standardless quantitative x-ray analysis ». Proceedings, annual meeting, Electron Microscopy Society of America 50, no 2 (août 1992) : 1650–51. http://dx.doi.org/10.1017/s0424820100132881.

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The ϕ(ρz) models developed during the recent years (Gaussian, PAP, XPP) have been shown by several authors to improve significantly the capability of quantitative x-ray microanalysis, mainly in the field of light elements, tilted specimens, and layered specimens. An increasing number of users is now able to take advantage of these models, since some of them have been implemented in EPMA or EDS commercial softwares.However, most of the reported successful applications are the result of analyses with standards, where the basic data are the relative x-ray intensities (also called k-ratios). Indeed, analyses with standards are well adapted to the electron microprobes, and permit to obtain very accurate results. But in the scanning electron microscopes (SEM), the operations of acquiring, processing and handling the EDS spectra of all the required standards are really time consuming. It is why an EDS standardless mode giving satisfactory quantitative results would be so useful, even for those laboratories which can also operate an electron microprobe for the applications requiring the highest degree of accuracy.
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4

Rodríguez, T., S. Limandri, S. Suárez, I. Ortega-Feliu et J. Trincavelli. « Standardless semi-quantitative analysis by PIXE ». Journal of Analytical Atomic Spectrometry 32, no 5 (2017) : 1020–30. http://dx.doi.org/10.1039/c7ja00068e.

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Zangalis, K. P. « Standardless quantitative mineralogical analysis of rocks ». Powder Diffraction 13, no 2 (juin 1998) : 74–84. http://dx.doi.org/10.1017/s0885715600009891.

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The main difficulty in the quantitative mineral analysis of rocks is connected with the variable nature of the mineral species. In the present paper a combined method (and a corresponding computer program) is proposed, which practically overcomes this difficulty. This method is based on linear equations, which are a combination of the chemical mass-balance equations with those of the quantitative X-ray diffractometry, and can perform (completely or partly) both the quantification and the chemical characterization of the minerals on several rock samples simultaneously, demanding only easily accessible initial information, such as: (i) major element (oxide) compositions for the samples; (ii) qualitative mineral composition of the samples; (iii) X-ray intensities for one or few nonoverlapped reflections of the crystalline minerals (not necessarily of all): (iv) some characteristic data for the phases (i.e., chemical composition data), if these are accurately known. Where it is possible the minerals may be expressed via end members. The samples may contain amorphous phases and/or phases without X-ray data. From the general case some very simple partial cases are derived, demanding less initial information. This method has the following advantages over the previous ones of similar philosophy: (i) drastic reduction of the number of required samples; (ii) sufficiency of equations for any analytical problem; (iii) possibility of performing partial analysis when a complete one is impossible; (iv) possibility of using the same end member in more than one solid solution. Analysis examples are given.
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6

Ritchie, Nicholas W. M., et Dale E. Newbury. « Standardless Analysis - Better but Still Risky ». Microscopy and Microanalysis 20, S3 (août 2014) : 696–97. http://dx.doi.org/10.1017/s1431927614005200.

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7

Reed, S. B. J. « Approaches to Standardless Wavelength Dispersive Analysis ». Microscopy and Microanalysis 6, no 2 (mars 2000) : 145–49. http://dx.doi.org/10.1007/s100059910016.

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In truly standardless electron microprobe analysis, generated X-ray intensities calculated from first principles are combined with a detector efficiency model. Though already used for energy dispersive (ED) analysis, the application of this concept to wavelength dispersive (WD) analysis is problematic, mainly because the reflectivity of spectrometer crystals is not well known. However, the need to carry out standard measurements with every batch of WD analyses can be avoided by using stored intensity data, and interpolation may be used when no standard is available. An empirical adjustment factor allowing for changes in spectrometer efficiency with time can be applied as necessitated by the variability of the spectrometer characteristics and the accuracy required. A similar approach to background corrections, based on measured continuum intensities, can be used. While the convenience of standardless WD analysis is attainable only at the expense of reduced accuracy, it can have a useful role where high accuracy is not needed or as a preliminary to applying a more rigorous routine using standards.
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8

Jinsheng, Lu, Xie Ronghou, Tan Xiaoqun et C. Nieuwenhuizen. « Optimizing the Calculation of Standardless Quantitative Analysis ». Advances in X-ray Analysis 32 (1988) : 515–22. http://dx.doi.org/10.1154/s037603080002084x.

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A method for quantitative phase analysis without standards (QPAWS) has been published in 1977 and has gained considerable interest, as the calibration for quantitative XRD may sometimes be difficult. Standards for quantitatative XRD are not generally available, and in many cases even the pure phases cannot be obtained.The QPAWS method is based on (i) analysis of all phases present in the samples, (ii) foreknowledge of mass absorption coefficients (MAC)(iii) measuring samples which contain all phases in varying concentrations. In this method the number of samples used is equal to the number of phases to be analysed.
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9

Pouchou, Jean-Louis. « Standardless X-ray analysis of bulk specimens ». Mikrochimica Acta 114-115, no 1 (décembre 1994) : 33–52. http://dx.doi.org/10.1007/bf01244532.

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10

Fournier, C�cile, Claude Merlet, Olivier Dugne et Michel Fialin. « Standardless semi-quantitative analysis with WDS-EPMA ». Journal of Analytical Atomic Spectrometry 14, no 3 (1999) : 381–86. http://dx.doi.org/10.1039/a807433j.

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11

Butyrskaya, E. V., L. S. Nechaeva, V. A. Shaposhnik et V. F. Selemenev. « Standardless structural-group analysis of supramolecular systems ». Journal of Analytical Chemistry 64, no 10 (octobre 2009) : 1000–1006. http://dx.doi.org/10.1134/s1061934809100049.

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12

Barrea, Raúl A., et Raúl T. Mainardi. « Standardless XRF analysis of stainless-steel samples ». X-Ray Spectrometry 27, no 2 (mars 1998) : 111–16. http://dx.doi.org/10.1002/(sici)1097-4539(199803/04)27:2<111 ::aid-xrs259>3.0.co;2-3.

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13

Li, X., J. Xingxing, W. Zi-qin, R. J. Lee, G. R. Dunmyre et K. L. Anderson. « Thin film standardless analysis used in TEM asbestos EDS analysis ». Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988) : 966–67. http://dx.doi.org/10.1017/s0424820100106892.

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A thin film standardless analysis method, based on the Cliff-Loriner factor k, has been used to do quantitative x-ray analysis of asbestos fibers in the TEM. The results of the analysis of four minerals at 120 keV were close to the theoretical value. The ionization cross section Q has been revised experimentally to improve the analysis of asbestos.The Cliff-Lorimer factor has been used in TEM thin film analysis since 1975. The factor kAB is used in the following equation:CA/CB = kAB IA/IBwhere CA and CB is the weight percent of the elements A and B. The IA and IB are x-ray intensities corresponding to elements A and B. In this paper the calculated k values2 will be used for standardless quantitative analysis.In the thin film, when the effects of the backscattering electron, x-ray absorption, and secondary fluorescence are not considered, the x-ray intensity iswhere pt is the mass depth AA is the atomic weight of element A, W is the fluorescence yield, L is the ratio of the x-ray lines and T is the detector efficiency.
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14

Sandborg, A. O., R. A. Anderhalt, J. M. Dijkstra et R. B. Shen. « Standardless EDS Quantitative Analysis at High Tilt Angles ». Microscopy and Microanalysis 8, S02 (août 2002) : 1468–69. http://dx.doi.org/10.1017/s1431927602103977.

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15

Sarkar, M., S. Girardi, L. Guzman et F. Ferrari. « Standardless alloy analysis by detecting electron excited radiation ». Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment 255, no 1-2 (mars 1987) : 415–18. http://dx.doi.org/10.1016/0168-9002(87)91139-9.

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16

Wu, Ziqin. « Standardless EDS analysis of bulk and thin specimens ». Journal of Electron Microscopy Technique 7, no 4 (décembre 1987) : 323–29. http://dx.doi.org/10.1002/jemt.1060070412.

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17

Yakimov, I. « Retrieval system for qualitative and standardless quantitative phase analysis ». Acta Crystallographica Section A Foundations of Crystallography 63, a1 (22 août 2007) : s242—s243. http://dx.doi.org/10.1107/s0108767307094524.

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18

Zevin, L. S., et Sh L. Zevin. « Standardless Quantitative X-Ray Phase Analysis – Estimation of Precision ». Powder Diffraction 4, no 4 (décembre 1989) : 196–200. http://dx.doi.org/10.1017/s0885715600013713.

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AbstractQuantitative phase analysis of n-phase mixtures can be performed if at least n samples composed of no more than n identical phases are available. The fact that there is no need for pure phases (analytical standards) constitutes the main advantage of the method presented here. However, substitution for the pure phases by an unknown mixture of these phases decreases the diversity of the sample set and also the precision of the analysis. The crucial step in a standardless method is the creation of an initial sample set. A simple test is developed to estimate the suitability of the sample set for analysis and to evaluate the analysis error. Application of this test to 13 four-phase mixtures has confirmed its high quality.
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19

Baranov, V. I., L. A. Gribov et V. E. Dridger. « Computer modeling of standardless molecular spectral analysis of mixtures ». Journal of Analytical Chemistry 67, no 2 (février 2012) : 114–21. http://dx.doi.org/10.1134/s1061934812020049.

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20

Vecchiati, Giorgio, Francesco Fagioli, Giancarlo Torsi, Clinio Locatelli, Dionisio Mazzotta et Antonella Pagnoni. « Standardless Analysis of Hg with the Cold Vapor Method : Evaluation of the Best Use of Modern Instrumentation ». Applied Spectroscopy 56, no 7 (juillet 2002) : 859–62. http://dx.doi.org/10.1366/000370202760171527.

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The so-called cold vapor method is extensively used in atomic absorption spectroscopy for the quantitation of Hg and hydride forming elements. In the case of Hg it is possible to take advantage of the standardless method of analysis (which gives a quantitative result from a single measurement) if a stannous salt is used as a reducing agent. This type of analysis, which has the advantages of high sensitivity, low analysis time, and easy checking of the perfect working conditions of all the components of the apparatus, can be made with very slightly altered commercial instruments if flowmeters of good accuracy and precision are used. The mode of operation of modern commercial instruments can be either discontinuous, with a chromatographic-like injector, or continuous. A survey of the instruction manuals shows that virtually all manufacturers prefer the discontinuous mode. Our experimental results demonstrate that only with the continuous mode, if sufficient sample volume is available, is it possible to use the standardless method of analysis.
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21

Dijkstra, J. M., et R. B. Shen. « Standardless Quantification of Conductive Oxides In The Sem ». Microscopy and Microanalysis 3, S2 (août 1997) : 899–900. http://dx.doi.org/10.1017/s1431927600011387.

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In the last 10 years the development of new polymer type detector window materials has dramatically increased the opportunities for light element analysis with Energy Dispersive Spectrometers (EDS). With the introduction of light-element analysis the need also arises to accurately quantify X-ray spectra. Traditional quantification techniques, using a probe current measuring device and pure elemental standards, have been introduced into the field of EDS, but these techniques prevented much of the conveniences of the EDS techniques with respect to speed and ease of use. Many users are therefore willing to sacrifice part of the maximum achievable accuracy in return for a method that is more convenient: standardless analysis.With EDS analysis the widely published ZAF and φ(ρz) models can be used to convert relative intensities into weight percentages, but for standardless analysis the inaccuracy of the result is mainly caused by the reference intensities.
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22

Flude, Stephanie, Michael Haschke et Michael Storey. « Application of benchtop micro-XRF to geological materials ». Mineralogical Magazine 81, no 4 (août 2017) : 923–48. http://dx.doi.org/10.1180/minmag.2016.080.150.

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AbstractRecent developments in X-ray optics have allowed the development of a range of commercially available benchtop micro-XRF (μ-XRF) instruments that can produce X-ray spot sizes of 20–30 μm on the sample, allowing major- and trace-element analysis on a range of sample types and sizes with minimal sample preparation. Such instruments offer quantitative analysis using fundamental parameter based 'standardless' quantification algorithms. The accuracy and precision of this quantitative analysis on geological materials, and application of micro-XRF to wider geological problems is assessed using a single benchtop micro-XRF instrument. Quantitative analysis of internal reference materials and international standards shows that such instruments can provide highly reproducible data but that, for many silicate materials, standardless quantification is not accurate.Accuracy can be improved, however, by using a simple type-calibration against a reference material of similar matrix and composition. Qualitative analysis with micro-XRF can simplify and streamline sample characterization and processing for subsequent geochemical and isotopic analysis.
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Snyder, Robert L. « The Use of Reference Intensity Ratios in X-Ray Quantitative Analysis ». Powder Diffraction 7, no 4 (décembre 1992) : 186–93. http://dx.doi.org/10.1017/s0885715600018686.

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AbstractEach of the RIR based methods for carrying out quantitative X-ray powder diffraction analysis are described and a consistent set of notation is developed. The so called “standardless” analysis procedures are shown to be a special case of the internal-standard method of analysis where the normalizing assumption is used. All analytical methods, other than the Rietveld whole pattern matching procedure, require the use of explicitly measured standards, typically in the form of RIR values. However, if only semi-quantitative results can be tolerated, the standards may be obtained by using published RIR and relative intensity values. The exciting new techniques of whole pattern fitting and Rietveld constrained quantitative analysis are also described in RIR notation and shown also to be forms of the internal-standard method with the normalization assumption. The quantitative results obtained from Rietveld quantitative analysis are derived from computed standards in the form of computed, normalized, RIRN values. The normalization assumption in Rietveld analysis allows the exclusive use of computed standards and comes as close to a “standardless” analysis as one can achieve: relying on the absence of amorphous material and on the validity of the structural models. Relationships are given for obtaining quantitative analysis from these RIRN values obtainable from the least-squares scale factors.
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El-Sayed, Karimat, Z. K. Heiba et A. M. Abd El-Rahman. « The effect of peak choice on the quantitative phase analysis of the Egyptian kaolins using the standardless method ». Powder Diffraction 8, no 4 (décembre 1993) : 206–9. http://dx.doi.org/10.1017/s0885715600019369.

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The “standardless” quantitative phase analysis method proposed by Rius, Plana, and Planques [J. Appl. Cryst. 20, 457 (1987)] was evaluated by applying it to two series of artificial samples. The method was then applied to determine quantitatively the phases present in six different natural kaolin samples from Egypt. Two kaolinite peaks were selected for this analysis: One of them is known to be affected by stacking disorder, the other one is the 001 basal reflection, which is not significantly affected by stacking disorder. The method was also applied to samples of different mesh sizes. The results obtained when using the basal reflection showed that Egyptian kaolin is mainly kaolinite (82%–95%) together with anatase (2%–9%), rutile (1%–6%), and quartz (0.5%–7%). These analyses agreed very well with those obtained by chemical analysis. On the other hand, the analyses of the phases obtained from the peak which is strongly affected by stacking disorder were totally different. It was found also that by decreasing the particle sizes of kaolin samples the phase abundance of kaolinite increases, whereas those of quartz and anatase decrease. The results showed also that the standardless method is only applicable to peaks that are not strongly affected by structural disorder.
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Kataoka, Y., N. Masukawa et K. Toda. « A New User Oriented Intelligent XRF Spectrometer System ». Advances in X-ray Analysis 35, B (1991) : 1035–46. http://dx.doi.org/10.1154/s0376030800013276.

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The semi-quantitative analysis, which is called ‘Standardless Analysis’, plays a major role in X-ray fluorescent analysis, especially in the field of research and development. The main feature of the semi-quantitative analysis is the fact that the composition of a sample can be obtained directly from a qualitative scan without any prior knowledge of the sample.
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Alekseev, E. V., L. A. Gribov et S. G. Ivanov. « Possibilities of Density Functional Theory in Standardless Quantitative Spectral Analysis ». Journal of Analytical Chemistry 59, no 5 (mai 2004) : 407–11. http://dx.doi.org/10.1023/b:janc.0000026228.99578.cc.

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27

Dycus, J. Houston, Weizong Xu et James M. LeBeau. « Standardless EDS Composition Analysis using Quantitative Annular Dark-Field Imaging ». Microscopy and Microanalysis 23, S1 (juillet 2017) : 512–13. http://dx.doi.org/10.1017/s1431927617003245.

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28

Sitko, Rafał, et Beata Zawisza. « Calibration of wavelength-dispersive X-ray spectrometer for standardless analysis ». Spectrochimica Acta Part B : Atomic Spectroscopy 60, no 1 (janvier 2005) : 95–100. http://dx.doi.org/10.1016/j.sab.2004.11.004.

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Monakhova, Yu B., S. A. Astakhov et S. P. Mushtakova. « Standardless spectral analysis of independent mixture components : Experimental case studies ». Journal of Analytical Chemistry 64, no 5 (mai 2009) : 479–89. http://dx.doi.org/10.1134/s1061934809050098.

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Gribov, L. A., et V. A. Dement’ev. « From theory of spectra to standardless analysis of molecular objects ». Journal of Analytical Chemistry 67, no 5 (mai 2012) : 414–22. http://dx.doi.org/10.1134/s1061934812050073.

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Yakimov, I. S., P. S. Dubinin, A. N. Zaloga, O. E. Piksina et Ya I. Yakimov. « Regularization of methods of a standardless X-ray phase analysis ». Journal of Structural Chemistry 52, no 2 (avril 2011) : 319–25. http://dx.doi.org/10.1134/s0022476611020119.

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Tempesta, Gioacchino, et Giovanna Agrosì. « Standardless, minimally destructive chemical analysis of red beryls by means of Laser Induced Breakdown Spectroscopy ». European Journal of Mineralogy 28, no 3 (23 septembre 2016) : 571–80. http://dx.doi.org/10.1127/ejm/2016/0028-2529.

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Hu, B.-L., K. W. Jones, F. N. Tebbe, L. E. Firment et L. H. Brixner. « Application of nuclear reaction analysis to trace oxygen analysis in metal fluoride materials ». Journal of Materials Research 4, no 4 (août 1989) : 916–22. http://dx.doi.org/10.1557/jmr.1989.0916.

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Trace oxygen contamination of metal fluoride glasses degrades their performance in applications such as optical fibers or x-ray phosphors. Traditional methods for oxygen determination based on reaction with carbon to form carbon monoxide are slow and insensitive. We have used nuclear reaction analysis, in particular the 18O(p, α) reaction, to determine oxygen content in a variety of metal fluorides. Careful choice of the energy of the incident proton eliminates interference from fluorine. Standardless quantification of our measurements yields good agreement with the known oxygen content of mixtures of oxides and fluorides and with several (non-fluoride) NBS standards over four orders of magnitude. Measurement of 30 ppm oxygen has been demonstrated.
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Bogert, James R., Jack M. Kibler et Jack K. Schmotzer. « Standardless EDXRF Analysis of Cations in Ion-Exchange Resin-Impregnated Membranes ». Advances in X-ray Analysis 30 (1986) : 153–63. http://dx.doi.org/10.1154/s037603080002125x.

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In steam-generating systems of all types, producing and testing pure water is of utmost importance for the life of the system. A 1000-MWe (megawatt electric) power plant generates 6 million pounds of steam per hour if fossil fueled and 11 million pounds per hour if nuclear. Should an impurity have a concentration of only 10 ppb, in a year's time, 550 to 1000 pounds of solids can accumulate in the power-generating cycle. These solids may initiate numerous problems, including preboiler-cycle corrosion, boiler-tube failure, and turbine damage.At the Babcock & Wilcox (B&W) Alliance (Ohio) Research Center and throughout the industry, three principal methods are used to monitor water chemistry. On-line continuous analyzers measure parameters such as pH, conductivity, chloride, and sodium. Grab sampling (followed by laboratory analysis) is used for parameters that are measured less frequently; for example, sulfate. For some parameters, such as corrosion products, special sampling techniques are required. This is because no on-line instruments are available, and grab-samples are not chemically stable. Corrosion products are collected near the sample tap using a 0.45-micron filter-disc followed by a stack of resin-impregnated membranes.
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Statham, P. J. « Progress towards Accurate Quantitative Standardless X-ray Analysis at Low kV ». Microscopy and Microanalysis 20, S3 (août 2014) : 690–91. http://dx.doi.org/10.1017/s1431927614005170.

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Nurubeyli, T. K., Z. K. Nurubeyli, K. Z. Nuriyev et K. B. Gurbanov. « Standardless analysis of solids by mass spectrometry with inductively coupled plasma ». Technical Physics 62, no 2 (février 2017) : 305–9. http://dx.doi.org/10.1134/s1063784217020220.

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Rublinetskaya, Yu V., E. O. Il’inykh et V. V. Slepushkin. « A standardless method for the local electrochemical analysis of homogeneous alloys ». Journal of Analytical Chemistry 66, no 1 (janvier 2011) : 84–87. http://dx.doi.org/10.1134/s1061934810111024.

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Elam, W. T., R. B. Shen, B. Scruggs et J. Nicolosi. « F05 Standardless FP Analysis of Thin Films and Multiple Layer Coatings ». Powder Diffraction 18, no 2 (juin 2003) : 180. http://dx.doi.org/10.1154/1.1755147.

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Trincavelli, J., et R. Van Grieken. « Peak-to-background method for standardless electron microprobe analysis of particles ». X-Ray Spectrometry 23, no 6 (novembre 1994) : 254–60. http://dx.doi.org/10.1002/xrs.1300230605.

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Li, D. Y., et B. H. O'Connor. « A Multi-Line Standardless Method for X-Ray Powder Diffraction Phase Analysis ». Advances in X-ray Analysis 35, A (1991) : 105–10. http://dx.doi.org/10.1154/s0376030800008727.

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AbstractQuantitative phase analysis (QPA) methods which employ only one diffraction line for each phase arc generally unreliable due to the influence of systematic errors such as preferred orientation and extinction. Gazzara and Messier (1977) proposed a multi-line QPA method using normalised line intensities for line j of phase i,where Iij = measured Bragg intensity, m = multiplicity, Lp = Lorentz-polarisation factor, |F| = structure amplitude and Vi = cell volume. The method proposed here is a refinement of the Gazzara-Messier procedure. Phase compositions are calculated directly from the mean normalised Intensity for resolved lines which span the 2θ range of the instrument. The method makes use of the variance in to estimate standard deviations for the phase compositions. Test results are given for binaries of corundum-quartz and corundum-ceria.
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Paterson, J. H., J. N. Chapman, W. A. P. Nicholson et J. M. Titchmarsh. « Characteristic X-ray production cross-sections for standardless elemental analysis in EDX ». Journal of Microscopy 154, no 1 (avril 1989) : 1–17. http://dx.doi.org/10.1111/j.1365-2818.1989.tb00563.x.

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Mazumdar, Sujata. « A standardless method of quantitative ceramic analysis using X-ray powder diffraction ». Journal of Applied Crystallography 32, no 3 (1 juin 1999) : 381–86. http://dx.doi.org/10.1107/s0021889898012898.

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A new procedure using X-ray powder diffraction data for quantitative estimation of the crystalline as well as the amorphous phase in ceramics is described. Classification of the crystalline and amorphous X-ray scattering was achieved by comparison of the slopes at two successive points of the powder pattern at scattering angles at which the crystalline and amorphous phases superimpose. If the second slope exceeds the first by a stipulated value, the intensity is taken as crystalline; otherwise the scattering is considered as amorphous. Crystalline phase analysis is obtained by linear programming techniques using the concept that each observed X-ray diffraction peak has contributions fromncomponent phases, the proportionate analysis of which is required. The method does not require the measurement of calibration data for use as an internal standard, but knowledge of the approximate crystal structure of each phase of interest in the mixture is necessary. The technique is also helpful in qualitative analysis because each suspected phase is characterized by the probability that it will be present when a reflection zone is considered in which the suspected crystalline phase could contribute. The amorphous phases are determined prior to the crystalline ones. The method is applied to ceramic materials and some results are presented.
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Cross, B. J. « F21 Standardless eds analysis—the influence of X-ray detector models—invited ». Powder Diffraction 21, no 2 (juin 2006) : 173. http://dx.doi.org/10.1154/1.2219808.

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D'Angelo, J., E. Perino, E. Marchevsky et J. A. Riveros. « Standardless analysis of small amounts of mineral samples by SR-XRF and conventional XRF analyses ». X-Ray Spectrometry 31, no 6 (2002) : 419–23. http://dx.doi.org/10.1002/xrs.597.

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Ratt, Giuliana. « Chemical analysis methods and resources ». Revista do Museu de Arqueologia e Etnologia. Suplemento, supl.2 (10 décembre 1997) : 81. http://dx.doi.org/10.11606/issn.2594-5939.revmaesupl.1997.113442.

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Análises químicas dos mais variados materiais têm sido normalmente feitas, por várias técnicas, e são uma ferramenta importante para a confecção e controle de produtos em geral. A experiência adquirida pelos analistas pode ser importante para um maior conhecimento de amostras desconhecidas, sem histórico ou procedência, como materiais confeccionados pelo Homem em sua caminhada rumo aos dias atuais. Os recursos que a análise química oferece são o conhecimento dos elementos presentes e sua quantidade. Através destas informações, muitas conclusões quanto a origem, características e peculiaridades podem ser obtidas, por estudiosos dos materiais analisados. Os métodos de análise química atualmente disponíveis são ágeis e precisos, aplicando-se aos mais variados materiais e revelando sua composição qualitativa e quantitativa. A maioria é destrutiva, isto é, altera completamente a amostra para a análise, mas técnicas não destrutivas também estão disponíveis, podendo ser de grande valia para estudos arqueológicos, principalmente se acopladas aos novos softwares standardless que permitem análises sem padrões similares.
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Meor Sulaiman, Meor Yusoff, Nursaidatul Syafadillah Kamaruzaman et Ahmad Khairulikram Zahari. « Standardless EDXRF Analysis Methods of U and Th in Malaysian Tin Slag Waste ». Materials Science Forum 840 (janvier 2016) : 410–15. http://dx.doi.org/10.4028/www.scientific.net/msf.840.410.

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Accurate quantification of uranium and thorium elements was performed in the absence of standards for the XRF analysis. This quantification method uses standard addition method. The standard addition method was first established by performing a micofocus XRF onto a sample. In the calibration graphs of uranium, the R2 was 0.9997 white the R2 value for thorium was 0.9915. Once the baseline quantity of both uranium and thorium were obtained, they were used to normalize all the quantification of other samples prepared by grab and vibratory methods. It was found out that the vibratory method gives more accurate results.
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Yatkin, S., et M. Gerboles. « Evaluation of EDXRF results from PM 10 using standardless analysis and external calibration ». Microchemical Journal 133 (juillet 2017) : 423–30. http://dx.doi.org/10.1016/j.microc.2017.04.003.

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Rius, J., F. Plana et A. Palanques. « A standardless X-ray diffraction method for the quantitative analysis of multiphase mixtures ». Journal of Applied Crystallography 20, no 6 (1 décembre 1987) : 457–60. http://dx.doi.org/10.1107/s0021889887086217.

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An X-ray diffraction method is described that determines calibration constants using only diffracted intensities and calculated phase absorption coefficients through a least-squares procedure. The conditions necessary for the application of this method are that the qualitative analysis be complete, that sufficient samples with essential differences in the quantitative phase composition be available and that the chemical compositions of the phases be known approximately. It does not require the use of pure phases or the measuring of the sample absorption coefficients. It allows the easy introduction of known calibration constants, thus reducing the number of samples needed and increasing the versatility of the method.
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Zangalis, K. P. « A standardless method of quantitative mineral analysis using X-ray and chemical data ». Journal of Applied Crystallography 24, no 3 (1 juin 1991) : 197–202. http://dx.doi.org/10.1107/s0021889890013851.

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Behrens, K., et B. Burton. « F39 Directly from EDX Spectrum to Concentrations - A New Approach to Standardless Analysis ». Powder Diffraction 18, no 2 (juin 2003) : 181. http://dx.doi.org/10.1154/1.1755160.

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