X-ray diffraction profiles

X-ray diffraction with facilities for determining the intensity profile of each diffraction line is particularly informative. Criteria which have been adopted as evidence of good bulk homogeneity (54) are (1) a correct lattice constant eto, and (2) a symmetrical X-ray diffraction profile. A method has also been described (30) for determining if a range of lattice... 

Fig. 9. X-ray diffraction profiles from (111) planes of Pd-Rh films, prepared at 400°C and used in catalytic reaction (60).

Fig. 22. X-ray diffraction profiles (111 planes) from 99% Pd-Ag films treated as described in text unresolved trace, solid line K

X-ray diffraction profile, 26 417 X-ray diffractometers commonly used, 26 422 X-ray effect, 20 661 X-ray electromagnetic spectrum,... 

Figure 24 Powder X-ray diffraction profiles for (Si-n-Dec, 90, at different temperatures.260 Reprinted with permission from Chunwachirasiri, W. West, R. Winokur, M. J. Macromolecules 2000, 33, 9720-9731. 2000 American Chemical Society.

FIGURE 5.7 X-ray diffraction profiles of native (ungelatinized), partially gelatinized, and completely gelatinized (amorphous) tapioca starch. Reprinted from Carbohydrate Polymers, Vol. 67, Ratnayake and Jackson (2007), A new insight into the gelatinization process of native starches. Pages 511-529, 2007, with permission from Elsevier. 

Fig. 4. Wide angle x-ray diffraction profile of imide-aryl ether phenylquinoxaline block copolymers (a) 2c and (b) 2d...

Fig. 16 Experimental (-1- marks), calculated solid line) and difference lower line) powder X-ray diffraction profiles for the three-component material after final Rietveld refinement, as reported by the authors [64]. (Reprinted with permission from Cheung et al. (2003) J Am Chem Soc 125 14658. Copyright 2003 American Chemical Society)...

We can learn the structural change in the crystals during topochemical polymerization by powder X-ray diffraction measurements. X-ray diffraction profiles continuously changed during the polymerization of 1 under the irradiation of an X-ray beam (Fig. 5) [51]. The reflections shifted and approached the reflection position of the polymer. This suggests that the polymerization... 

Fig. 5 Time dependence of X-ray diffraction profiles measured for the powder crystals of 1 at room temperature [51]...

Immediately after the isolation of macroscopic quantities of Cgo solid [298], highly conducting [299] and superconducting [141] behaviors were verified for the K-doped compounds prepared by a vapor-solid reaction (Haddon, Hebard, et al.). Crystallographic study based on the powder X-ray diffraction profile revealed that the composition of the superconducting phase is KsCeo and the diffraction pattern can be indexed to be a face-centered cubic (fee) structure with a three-dimensional electronic pathway [300]. The lattice parameter (a = 14.24 A) is apparently expanded relative to the undoped cubic Ceo = 14.17 A). The superconductivity has been observed for many A3C60 (A alkali metal), e.g., RbsCeo (Tc = 29 K... 

Figure 8.3 Wide angle X-ray diffraction profile of potato starch.

Figure 2.1 X-ray diffraction profile of silicon ferrierite. Difference Profile is also shown. Data from Brookhaven Laboratory.

In order to obtain detailed structure, a knowledge of diffraction intensities is essential, the intensities being related to the structure factor. Computer-controlled single-crystal X-ray diffractometers with structure (software) packages have made structure elucidation a routine matter. The availability of synchrotron X-radiation of continuously variable wavelength has made X-ray diffraction a still more powerful structural tool for the study of solids. A technique of great utility to solid state chemists is the Rietveld treatment of powder X-ray diffraction profiles (Rietveld, 1969 Manohar, 1983). Automated structure packages for the determination of unknown structures by this method are now commercially available (see section 2.2.3). In Fig. 2.1, we show a typical set of profile data. 

Fig. 23 (a) Small-angle X-ray diffraction profile of EDOPC lipoplexes at 4 1 lipid/DNA weight ratio (arrow points to the peak originating from DNA-DNA in-plane correlation) inset, thin-section electron microscopy image of EDOPC lipoplexes (reproduced with permission from [81] copyright (2007) Elsevier), (b) Electron density profiles of the lipid bilayer in presence and in absence of DNA [16] (copyright (2000) Biophysical Society)... 

Inspection of the synchrotron X-ray diffraction profiles of Sm2 75C60 readily reveals the appearance of superlattice peaks at low angles that index to the enlarged... 

There are other factors affecting the intensity of the peaks on a x-ray diffraction profile of a powdered sample. We have analyzed the structure factor, the polarization factor, and the broadening of the lines because of the dimensions of the crystallites. Now, we will analyze the multiplicity factor, the Lorentz factor, the absorption factor, the temperature factor, and the texture factor [21,22,24,26],... 

Afterward, the x-ray diffraction profiles of the treated samples were obtained, by irradiating the side where the Ni was electrodeposited [34], and the intensity Aa of the (221) peak of the a-Fe, body-centered cubic phase, and the intensity A.( of the (220) peak corresponding to the y-FeNi, face-centered cubic alloy were measured [34,35],... 

Figure 2. Experimental (—) and calculated ( ) X-ray diffraction profile for H-BOR-E, sample 10 (a) and 23 (b). The insets show a plot of the intensity disagreement factor (see Table II) vs. the fault probability parameter, p.

Figure 5. Calculated powder X-ray diffraction profiles for the FAU (a) and BSS frameworks (b) and the sum of these two components in the ratio BSS FAU = 3.0 (c) which approximates observed profiles for zeolite ZSM-20 materials (lower vertical bars- positions of allowed reflections).

Fig. 8 Experimental (+), calculated (solid line) and difference (lower line) powder X-ray diffraction profiles for the Rietveld refinement of Ph2P(0).(CH2)7.P(0)Ph2. Reflection positions are marked. The calculated powder diffraction profile is for the final refined crystal structure...

Fig. 4. X-Ray diffraction profiles of products obtained at various temperatures from the mixture of 1 mol NdjOj and 2 mol EuF3...

Increase in fluorination temperature would enhance the covalency of C—F bond and destruction of the layered carbon skeleton by C—C bond rupture as indicated by X-ray diffraction profiles shown in Fig. 9. The C—C bond rupture leads to... 

Powder X-ray diffraction profiles of the samples that were heated to 77, 100, 132, and... 

Figure 9.8 Powder X-ray diffraction profiles (in situ measurements) at (a) 76 and (b) 87 °C. These measurements were carried out under vacuum, Ref [20].

The evolution of US-induced crystallization around the glass transition temperature for metallic glass was monitored by electromagnetic acoustic resonance, which allowed resonance frequencies and internal frictions to be measured. In an as-cast glassy sample, such frequencies jumped up just above the glass temperature transition at the beginning of the process under ultrasonic vibration this was ascribed to nano-crystallization as confirmed by an X-ray diffraction profile, which was absent in the absence of US. Irregular A-shaped internal-friction peaks were also observed prior to abrupt crystallization [48]. 

Figs. 3 and 4 show the X-ray diffraction profiles of the ACFs/Cu catalysts before and after catalytic reactions, respectively. The copper metal (Cu), which the difftaction patterns revealed around 26 43 and 50° on ACFs/Cu, is oxidized to CU2O (26 36 and 42) during No catalytic reduction process. The surftices of ACFs/Cu catalyst are found to scavenge the oxygen released by catalytic reduction of NO, which can be explained by the presence of another nitric oxide reduction mechanism between ACFs and ACFs/Cu catalysts. 

Figure 4. X-ray diffraction profiles after the NO-ACFs/Cu catalysts reaction at SOOt) (a) ACFs, (b) ACFs/Cu5, (c)ACFs/CulO.

Figure 26 shows wide-angle X-ray diffraction profiles of CB with ultrasonication of three durations and without ultrasonication taken after cooling at 20°C from... 

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