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X-ray diffraction peak intensity

D-3906 Relative Zeolite Diffraction Intensities Relative fraction of zeolite as determined by comparing x-ray diffraction peak intensities... [Pg.437]

Mineral data (relative concentations) are available for most samples from the CR-2 core (16) and the 01-A core (17). Bulk mineralogy was determined X-ray diffraction using nickel-filtered CuKmineral data are reported in X-ray diffraction peak intensities for the following minerals ... [Pg.257]

Semiquantitative estimates of the relative abundances of siderite, calcite and ferroan dolomite/ ankerite were made by comparing corrected XRD (X-ray diffraction) peak intensities using the method of Lynch (1997). [Pg.89]

J. Ruska, L.J. Gauckler, J. Lorenz and H.U. Rexer, The Quantitative Calculation of SiC Polytypes from Measurements of X-Ray Diffraction Peak Intensities, J. Mater. ScL, 14, 2013-2017 (1979). [Pg.183]

For the catalyst based on Mo10V0.33Nb0.nTe0.22Ox, a precise phase composition is claimed, as defined by the ratio of the X-ray diffraction peak intensity at 20 27.3° and 28.2° (CuKa), which minimizes the combustion of ammonia to N2 [29d,j]. [Pg.297]

The main method used to distinguish the relative quantities of neoformed illite is by the polymorph or structure of the material. Using the criteria that 2M and 3T polymorphs of dioctahedral potassic mica are high temperature forms (Velde, 1965a), the determination of the relative quantities of lMd, and 1M vs. 2M, 3T polymorphs permits a semi-quantitative estimation of the proportion of neo-formed or low temperature illite present in a specimen. A method commonly used is a determination of relative intensities of X-ray diffraction peaks of non-oriented mica (Velde and Hower, 1963 Maxwell and Hower, 1967). Usually only 2M and lMd polymorphs are present in illite specimens which simplifies the problem. The 1M polymorph is typical of ferric illites and celadonite-glauconites, the more tetrasilicic types. [Pg.38]

The hydrothermal stability of samples A and B was studied by treating the samples in boiling water for l and 2 days and the treated samples were again characterized by XRD and BET measurements. Figure l displays the XRD patterns of samples A and B treated in boiling water at different time. After treatment in boiling water for 2 days, the intensity of X-ray diffraction peaks for samples A and B decreases proportionately with treatment time. It can be clearly observed that the drop in the intensity of [ 100] diffraction peak for sample B is more drastic than sample A. After only l day in boiling... [Pg.52]

Crystals may not be too perfect The condition for Bragg139 reflection, Eq. (8.3.2), is also the condition for total internal reflection. Thus, an absolutely perfect millimeter-sized crystal will reflect internally almost all of the X-ray beam, even at the Bragg angles. However, each crystal contains crystalline domains, 1-10 pm in size, which are slightly misaligned with each other (by seconds or a few minutes of a degree) this is what permits the observation of X-ray diffraction peaks. If the diffracted intensity is unacceptably low, a quick thermal shock to the crystal may help micro-shatter the crystal and form those domains. [Pg.744]

As shown in Fig. 7.15, all the X-ray diffraction peaks of CPI.5, CPI. 67 and CP2 samples belong to HAp. As the Ca/P molar ratio deacases from 1.375, the peak intensity of HAp decreases appreciably, while that of monetite and brushite increases. The effect of NH3 adding is shown in Fig. 7.16. [Pg.156]

Figure 24. Relative intensity of small-angle X-ray diffraction peaks and DCS thermopeaks of bulk anhydrous milkfat taken during a slow cooling process. Figure 24. Relative intensity of small-angle X-ray diffraction peaks and DCS thermopeaks of bulk anhydrous milkfat taken during a slow cooling process.
Figure 25. Relative intensity of smaii-angie X-ray diffraction peaks of cocoa butter without shear stress (closed) and shear stress (open). Figure 25. Relative intensity of smaii-angie X-ray diffraction peaks of cocoa butter without shear stress (closed) and shear stress (open).
As for the effects of the shear stress, it was shown by a Synchrotron radiation X-ray diffraction study that transformations from metastable to more stable forms, especially to Form V, were accelerated by high shear stress (110). Figure 25 shows the time variation of relative intensities of X-ray diffraction peaks of CB crystals formed after cooling from 50°C to 18°C at a rate of 3°C/min. In the case of no shear. Form III appeared at first after the temperature reached at 18°C, and then Form IV crystallized at the expense of Form III. On the other hand, applying the shear stress at 1440 s caused accelerated transformation from Form III to Form V, without the occurrence of Form IV. The same result was observed with lower shear rates (19), and the persistence time of Form III was reduced as the shear rate was increased. Mazaanti et al also observed that the orientation of CB crystals are aligned with the shear flow (110). These results indicated that temperature and shear treatments are the tools for tailoring the desired polymorphic structures of fats. [Pg.156]

H. Robson We know that the synthetic erionite product is highly crystalline from the intensity of x-ray diffraction peaks and the absence of the amorphous halo. Unfortunately, this does not prove the sample is fully crystalline. If amorphous material is present, it should be at a very low level. [Pg.424]

These results, i.c., the reduction in intensity of the elemental X-ray diffraction peaks and the formation of an ultralinc layered composite during the early stages of milling, and the coexistence of the quasicrystallinc phase with crystalline material for some period, are quite similar to what is known from amorphous phase formation by mechanical alloying (Sect. 3.3.2). The local... [Pg.110]

The injection-molded sheets sometimes include the hexagonal /1-crystal form. The fraction of j6-form can be estimated from the relative intensity (K-value) of X-ray diffraction peaks of j6-crystal according to Turner Jones et al. (88). As seen in... [Pg.259]

Anodier stone that has found wide cultural use as a carving medium in many early societies is steatite or soapstone, a very soft metamorphic rock related to chlorite and talc. In this laboratory, steatite (actually chlorite) from quarries near Tepe Yahya (Iran) was characterized by observation of the ratios of the relative intensities of basal-plane x-ray diffraction peaks after it was found that NAA-determined trace element concentrations varied wildly within a given specimen. Another technique that has been used involves the determination by NAA of a number of lanthanide elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Ho, Er, Tm, Yb and Lu) and the taxonomy of their abundances relative to each other — in other words, true pattern recognition , when plotted as ratios to the levels of the same elements in a standard reference chondrite Although this technique found successful provenience application... [Pg.76]

The intensities of the x-ray diffraction peaks were determined using a diffractometer with a monochromatic Cu K source. The intensities were measured with an NaI Tl scintillation counter coupled to a discriminator. The copper radiation was made monochromatic by an elastically bent sii le-crystal germanium plate cut along the (111) plane [2]. [Pg.15]

The changes in the X-ray diffraction patterns of mixtures of 30% flufenamic acid (FFA) and 70% of either florite R or florite S after storage at 0% RH and 40°C are shown in Fig. 1 [6]. In the mixture of FFA and florite R, the intensities of X-ray diffraction peaks due to FFA crystals gradually decreased with period of storage, and a halo pattern was observed after 5 weeks. In contrast, these X-ray diffraction peaks were still observed in the FFA-florite S mixture even after storage for 8... [Pg.775]

The art of filler dispersion in polymer matrix is easily determined by X-ray analysis especially WAXS analysis. The intensity and position of X-ray diffraction peaks reveals the exact idea regarding the morphological structure of polymer nanocomposites. Figure 22.11 compares reduced graphite oxide dispersions in NR matrix by different processes such as milling and solution casting methods. [Pg.658]

An example of the annealing effect on the small angle X-ray diffraction peak of 4.8 ATb/10.5 AFe before and after annealing at 250 C for 5 hours is illustrated in fig. 8a and b. The peak intensity decreases because of the intermixing between Tb and Fe atoms at the interface boundaries however, the layered structure still exists. [Pg.91]

X-ray diffraction peaks for unpoled, partially poled, and poled composites. The relative intensities of the (001) and (100) peaks are reversed in the unpoled and poled samples, which indicates near-saturation poling of the composites. Hence, a simple XRD technique can yield information about the electronic properties of... [Pg.205]

X-ray diffraction analysis indicates that the cellulose fibers formed from this solvent system exist in the cellulose III polymorph conformation. This polymorph structure is revealed by X-ray diffraction peaks at circa 20.8°, which correspond to both the (002) and (101) planes and another at circa 12.1° which corresponds to the (101) plane. The intensity of these X-ray diffraction peaks of the fiber suggests that it consists of a crystalline structure, in this case cellulose III crystals. As displayed in Table 12.2, the d(oo2) and d(ioi) are similar to those of cellulose III. These interplanar spacings are the average distance between the crystalline unit planes, and they are different from one cellulose polymorph to another. This suggests that the CH2OH moiety of the cellulose polymers are in the gg conformation and are free of... [Pg.377]


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See also in sourсe #XX -- [ Pg.38 , Pg.141 ]




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Diffraction intensity

Diffraction peaks

Peak intensities

Peaks intense

X-ray diffraction intensity

X-ray peaks

X-rays intensities

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