X-Ray Powder Diffraction XRPD

After supporting these sols on activated carbon, however, the obtained particle size depends on the capability of the protective agent to maintain the particle dimension. The obtained three catalysts, having different characteristics, are summarized in Table 3. As it is shown, mean size of gold nanoparticle obtained by TEM measurement did not always match with X-ray powder diffraction (XRPD) data. This result is not surprising as TEM measurements represent particle sizes, whereas from X-ray diffraction (XRD) it is possible to obtain crystallite dimensions that do not necessarily coincide with the size of... 

Microporous nanoparticles with ordered zeolitic structure such as Ti-Beta are used for incorporation into walls or deposition into pores of mesoporous materials to form the micro/mesoporous composite materials [1-3], Microporous particles need to be small enough to be successfully incorporated in the composite structure. This means that the zeolite synthesis has to be stopped as soon as the particles exhibit ordered zeolitic structure. To study the growth of Ti-Beta particles we used 29Si solid-state and liquid-state NMR spectroscopy combined with x-ray powder diffraction (XRPD) and high-resolution transmission electron microscopy (HRTEM). With these techniques we monitored zeolite formation from the initial precursor gel to the final Ti-Beta product. 

Although single-crystal x-ray diffraction undoubtedly represents the most powerful method for the characterization of crystalline materials, it does suffer from the drawback of requiring the existence of a suitable single crystal. Very early in the history of x-ray diffraction studies, it was recognized that the scattering of x-ray radiation by powdered crystalline solids could be used to obtain structural information, leading to the practice of x-ray powder diffraction (XRPD). 

Slurry experiments are a common method of determining which of two polymorphs is thermodynamically more stable. Samples of both polymorphs are added to a solvent and maintained at constant temperature, with agitation, for sufficient time for the stable polymorph to grow at the expense of the less stable form. The final solid form is analysed by X-Ray Powder Diffraction (XRPD) or similar. 

Indinavir sulfate, produced as the ethanolate using the synthetic process described in Section 2, is crystalline as determined by the x-ray powder diffraction (XRPD) method. The XRPD pattern and associated data, obtained using a Phillips Model APD 3720 x-ray diffractometer, is shown in Figure 3 and Table 1 [7]. 

The solid-state properties like crystallinity, polymorphism (crystal structure), shape (morphology), and particle size of drugs are important in the stability, dissolution, and processibility of drugs. Some commonly used methods in solid-state studies include microscopy, hot stage microscopy with polarized light, x-ray powder diffraction (XRPD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared FTIR/Raman, and solid-state NMR. 

The X-ray powder diffraction (XRPD) pattern of a sample of atorvastatin calcium, Form-I, was recorded at room temperature on Bruker D8 Advance diffractometer (Karlsruhe, Germany), using nickel-filtered Cu Ka radiation. The sample was mounted in a polymethylmethacrylate sample holder, and analyzed in a continuous mode with a step size of 0.01° and a step time of 1 s over an angular range of 3-40° 26. The XRPD results are found in Fig. 1.18 and in Table 1.3, being evaluated with the DIFFRACplus EVA (version 9.0) diffraction software. 

Figure 11.6 Some examples of x-ray powder diffraction (XRPD) patterns from bulk soils prepared by spray drying pairs are of the same soil sampled and then are resampled by returning to the same site more than 15 years later, are compared (a and b, both Ashintully c and d, both Glenshee).

Hillier, S. (2003). Quantitative analysis of clay and other minerals in sandstones by x-ray powder diffraction (XRPD). Int. Assoc. Sedimentol. Spec. Pub. 34, 213-251. 

Figure 2.30A shows the X-ray powder diffraction (XRPD) patterns of chifin and chitosan with different degree of deacetylation (DD). Five crystalline index (CrI) reflections 020, 110, 120, 101, and 130 from the lower... 

Further, several X-ray powder diffraction (XRPD) methods have been reported to determine glimepiride form I in its crystalline form. In some researches conducted by Ammar et al. [20,22,23], source of XRPD radiation used was the Cu with scanning range 5-80° and 26 step size. Tube voltage... 

The X-ray powder diffraction (XRPD) pattern (XD 490, Shimadzu, Japan) of magnesium silicate is shown in Fig. 7.12. Magnesium silicate clearly shows amorphous characteristics with broad peaks throughout the diffraction pattern range. Only three minor peaks are evident at 25-30°, 35-39°, and 58-61° 26. 

The first tasks of the work described in this paper were to define the chemical compositions of the vacuum-stable products derived from the interaction of graphite with AsF, AsF, mixed with F2, and OjAsF,. The second tasks were to explain the peculiar features of the X-ray powder diffraction (XRPD) pattern for the stage-one C,4AsF, (/, a 7.6 A). A novel structure involving fluoride ligand nestling of the AsF," in the hexagonal depressions of the carbon atom sheets is proposed. 

Detection and characterization of polymorphs and/or solvates rely on various experimental techniques. X-ray powder diffraction (XRPD), solid state nuclear magnetic resonance (NMR), solid state infrared (IR) and solid state Raman are useful in demonstrating differences in the solid state. Thermal analytical techniques, including differential thermal analysis (DTA), differential scanning calorimetry (DSC), and thermogravimetry (TG), are also... 

Various techniques are available for the investigation of the solid state. These include microscopy (including hot-stage microscopy, HSM), infrared spectrophotometry (IRS), single-crystal X-ray and X-ray powder diffraction (XRPD), thermal analysis, and dilatometry. 

X-ray powder diffraction (XRPD) is the analysis of a powder sample. The typical output is a plot of intensity versus the diffraction angle (20). Such a plot can be considered a fingerprint of the crystal structure, and is useful for determination of crystallographic sameness of samples by pattern comparison. A crystalline material will exhibit peaks indicative of reflections from specific atomic planes. The patterns are representative of the structure, but do not give positional information about the atoms in the molecule. One peak will be exhibited for all repeating planes with the same spacing. An amorphous sample, on the other hand, will exhibit a broad hump in the pattern called an amorphous halo, as shown in Fig. 5. 

In the case of DuP 747 (49), X-ray powder diffraction (XRPD), DSC, and thermomicroscopic studies determined the polymorphic system to be monotropic. Distinct diffuse reflectance IR, Raman, and solid-state 13C NMR spectra existed for each physical form. The complementary nature of IR and Raman gave evidence that the polymorphic pair were roughly equivalent in conformation. It was concluded that the polymorphic character of DuP 747 resulted from different modes of packing. Further crystallographic information is required in order to determine the crystal packing and molecular conformation of this polymorphic system. 

Figure 6.1, for example, shows the X-ray powder diffraction (XRPD) patterns of a sample of a compound as received and after ball milling. After ball milling for 1 h, the sample was rendered amorphous, and hence a shorter milling period was used. 

Electron diffraction data obtained along two orientations enabled the X-ray powder diffraction (XRPD) pattern of bornemanite to be indexed and the following crystal data to be obtained space group /life lattice parameters a = 5.498,... 

Different preparation routes lead to powders with different electrochemical performance, so, in order to investigate this aspect, we have prepared, by two different methods, series of LiCOyNi(. y)V04 (y=0, 0.2, 0.5, 0.8, 1) compounds. These powders have been characterized by X-ray powder diffraction (XRPD), diffUse reflectance Vis-NIR and NMR spectroscopies. 

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