Quantitation X-ray diffraction

Omotoso, O. E., Ivey, D. G. Mikula, R. 1998a. Hexavalent chromium in tricalcium silicate Part 1 Quantitative X-ray diffraction analysis of crystalline hydration products. Journal of Materials Science, 33, 507-513. 

Our previous studies [22] showed that the uncalcined MCM-41 and lamellar phases prepared using the same surfactant as a template exhibit dramatically different thermogravimetric behavior, which manifests itself in distinctly different temperatures of the weight change events. This provided a clear opportunity for detection of lamellar constituents in MCM-41 and for quantitative determination of the composition of MCM-41/lamellar mixed samples. Indeed, the percentages of the lamellar phases in these samples assessed from the TGA data were remarkably close to those obtained using quantitative X-ray diffraction and gas adsorption analysis [22]. This demonstrated that in favorable cases, TGA can be used for semi-quantitative determination of the phase composition of MMSs. 

Silicon is a constituent of the main phase as well as of the most common impurities SiC, free Si, Si2N20, Si02, FeSix. Therefore, besides the determination of the total amount of Si, additional methods are needed to determine the amounts of free Si and the other compounds. Quantitative X-ray diffraction (XRD) is often used with modern XRD methods less than 0.1 wt.% free Si [232] and 0.2 wt.% Si2N20 [228] are detectable. The accuracy for SiC is somewhat lower due to the overlapping of the main peak of SiC with / -Si3N4. Free Si can be determined also with volumetric methods [225]. 

Sturges, W.T., Harrison, R.M. and Barrie, LA. (1989) Semi-quantitative X-ray diffraction analysis of size fractionated atmospheric particles. Atmos. Environ., 23, 1083-1098. 

X-ray Diffraction Analysis. The inorganic components of paper are the most suitable ones for quantitative X-ray diffraction analysis. Most of these compounds are minerals and are present as fillers, coatings and pigments (often whiteners) which are added to improve the properties of the paper. Examples of compounds commonly added to paper are alumina, aluminum silicate, barium sulfate, calcium carbonate, calcium sulfate, calcium sul-foaluminate, iron oxide, magnesium silicate, silica, titanium dioxide, zinc oxide, and zinc sulfide (28). Some of these, e.g., calcium carbonate and titanium dioxide, may be present in any of... 

This type of analysis would be helpful in the identification stage of the quantitative X-ray diffraction analysis method described in the previous section however, it appears that, by itself, X-ray microanalysis only of isolated particles will not... 

A quantitative X-ray diffraction study of the Cu/ZnO catalysts (41) has revealed that varying amounts of copper appear in an X-ray amorphous... 

Srodon, J., V. A. Drits, D. K. McCarty, J. C. C. Hsieh, and D. D. Eberl. 2001. Quantitative X-ray diffraction analysis of clay-bearing rocks from random preparations. Clays Clay Miner. 49 514—528. 

As noted above, the traditional methods of quantitative analysis make use of one or a small number of non-overlapping peaks from the diffraction patterns of the different component (e.g. polymorphic) phases. With the advent of more powerful laboratory X-ray sources and synchrotron radiation, faster and more sensitive detectors, computer controlled diffractometers and the almost universal use of digitized data there is increasing use of the full diffraction pattern for quantitative X-ray diffraction analysis (Zevin and Kimmel 1995). 

N. J. Elton and P. D. Salt, Particle statistics in quantitative X-ray diffract-ometry, Powder Dijfr., 1996, 11, 218-229. 

X-ray Diffraction. X-ray diffraction is the most extensively developed and universally applied method for characterization of minerals in coal and other rocks. This method is capable of giving quantitative results of major minerals in coal, coal ash, and coal-related materials accurate to about + 5-7 percent absolute ( ). Quantitative X-ray diffraction is difficult. A general overview of the method with many references is provided by Herzenberg (53). 

The ASTM F 1185 designation specifies chemical and crystallographic requirements for hydroxyapatite applied to the surfaces of surgical implants. Elemental analyses for calcium and phosphorus will confirm the expected stoichiometry of hydroxyapatite. The calcium and phosphorus contents will be determined by a suitable method such as ion chromatography. A quantitative X-ray diffraction analysis will determine a hydroxyapatite content of at least 95%. The concentration of deleterious trace elements such as arsenic, cadmium, mercury and lead will be assessed for hydroxyapatite derived from natural resources. The analysis of other trace elements may be required, based on the conditions, apparatus or environments specific to the manufacturing techniques and raw materials. Inductively coupled plasma/mass spectroscopy (ICP/MS), atomic absorption (AAS) or the... 

Fs-laser-induced ps X-ray generation has also been demonstrated in the laboratory by exploiting the high spatial and spectral brightness of plasmas that, once created, emit X-ray pulses on a time scale of order ps and typically with a kHz rate of repetition [60, 61]. The development of these instrumental advances for affording laboratory-based, quantitative X-ray-diffraction results would prove highly beneficial to this area of structural endeavour. 

In addition small-scale exposures at 870"C were used to study further the role of water vapour with 20 vol.-% and 30 vol.-% water vapour in air in an alumina tube furnace. Phase morphology was studied with scanning electron microscope (SEM). To distinguish between the glassy and crystalline phases some samples were etched in 2-% HF-solution. Phase composition was determined by a quantitative X-ray diffraction (XRD) analysis based on the internal standard, Cap2, method. The chemical composition of the amorphous phase in the binder was determined locally with EDS analysis in SEM. A bulk chemical analysis of the amorphous phases in binder was performed by Induction Coupled Plasma Mass-Spectrometry (ICP-MS). The samples were crushed powders of as-received and 500 h at water vapour bulk exposed (w) materials. The glassy phase was dissolved in HF-HNO3 solution. Open porosity, apparent and bulk densities of each specimen were determined by Archimedes method before and after the tests. 

Bish, D. L., 1994. Quantitative X-Ray diffraction analysis of soils. In Amonette, J. E. L. W. Zelanzny (eds.) Quantitative Methods in Soil Mineralogy. Soil Science Society of America, Inc., Madison, Wisconsin 267-295. 

Cody, R. D. G. L. Thompson, 1976. Quantitative X-ray diffraction analyses of clays using an orienting internal standard and pressed disc of bulk shale samples. Clays Clay Mineral. 24 224-231. 

Tien, P.-L., 1974. A simple device for smearing clay-on-glass slides for quantitative X-ray diffraction studies. Clays Clay Minerals 22 367-368. 

Connolly, J. R. (2010) Introduction quantitative X-ray diffraction methods . Spring Chung, F. H. (1974) Quantitative interpretation of X-ray diffraction patterns. I. Matrix-flushing method of quantitative multicomponent analysis /. Appl. Crystallography, 7,519-525. 

Mechanochemical reaction mechanism in the Na2CO Nb20s system studied by a combination of quantitative X-ray diffraction, thermal and infrared spectroscopy analysis... 

Quantitative X-ray diffraction, infrared spectroscopy and thermogravimetric analysis... 

The glass content in granulated blast furnace slags may be determined as the difference between the total and the content of crystalline phases as determined by quantitative X-ray diffraction. Its amount may vary in different slags, and depends on their oxide... 

Powder X-ray diffraction has been applied to quantitative phase analysis (hereafter called QPA) for over 80 years. It seems that the first mention of QPA was made by Hull in the paper A new method of chemical analysis , published in 1919 in the Journal of the American Chemical Society. At this early stage, quantitative X-ray diffraction (QXRD) was based on a comparison of diffraction line intensities for the analyzed sample with a series of mixtures containing known amounts of the analyte. 

This approach has been used by Bonanos et al. [1984a] to study PSZ of composition ZrOa with 8 mole % CaO (Ca-PSZ). XRD and TEM showed the t m transformation to be complete after 20 h of heat treatment at 1400°C, while quantitative x-ray diffraction analysis gave a value of 0.3 for the volume fraction of the t component. Electron microscopy showed the t particles to be ellipsoidal, with axial ratios alb and bic of -2, for which Table 4.1.2 gives the corresponding form factors, 01 = 7.9, 02 = 2.5, 03 = 0.66. In short the parameters 0 and X2 in Eq. (23) are given and the only remaining variables are the complex conductivities Xjfi, Xff2, and y, . 

Bulk techniques like thermogravimetric analysis (TGA) and quantitative x-ray diffraction (QXRD) give information on the average volume fraction of particular phases, e.g. pores. 

Quantitative x-ray diffraction has been used to determine the degree of reaction of individual cement compounds present in cement. Some errors in these estimations are recognized. Figure 5 shows the fractional amounts of alite, belite, aluminate, and ferrite phases that hydrate in cement when hydrated for different times.These rates are not the same when the individual compounds are hydrated. 

Using the quantitative X-ray diffraction analysis the kinetics of the reaction at 1200°C has been investigated. As long as the amount of the perovskite phase can not be determined accurately from the X-ray diffraction data due to the peak overlapping, it was assumed that the conversion degree according to both mechanisms is almost the same after 3 hours heating. The error of such assumption is of the same order as the error of the X-ray quantitative analysis. 

The XRD analysis, involving qualitative and quantitative analysis, have been carried out on a home made BD—86 diffractometer, with Cu Ka radiation, Ni filter and a scintillation couter. The residual crystaHine TiOj after being dispersed on y—AI2O3 can be measmed by the matrix—flushing method (refs. 9—10) for quantitative X-ray diffraction analysis and calculated from the equation... 

Heat of hydration can be converted approximately into degree of hydration if the hydration enthalpies of the different clinker phases are known. Values for the clinker phases can be taken from Taylor (1997) see Table 2.1. These values can be used to calculate the enthalpy of complete hydration if the phase composition of a portland cement is known, e.g. by (extended) Bogue calculation (Taylor 1997) or by quantitative X-ray diffraction (XRD) analysis (see Chapter 5). This value can be used to roughly estimate the hydration degree from the cumulated heat development. For... 

Goetz-Neunhoeffer, F., and J. Neubauer (2006). Refined Ettringite (Ca5Al2(S04)3(0H)j2 26H20) Structure for Quantitative X-Ray Diffraction Analysis . Powder Diffraction 21 (1) 4-11. 

---