XRD pattern

The first analytical tool to assess tire quality of a zeolite is powder x-ray diffraction. A collection of simulated powder XRD patterns of zeolites and some disordered intergrowths togetlier witli crystallographic data is available from tlie IZA [4o]. Phase purity and x-ray crystallinity, which is arbitrarily defined as tlie ratio of tlie intensity of... 

Doping of alkali-metals into CNTs has been examined [11]. The X-ray powder diffraction (XRD) patterns of the K- or Rb-doped CNTs show that alkali-metals are intercalated between the CNT layers. The hexagonal unit cell is essentially the same as that of the stage-1 alkali-metal intercalated graphite ACg (A=K, Rb). For a sample doped with Rb, the observed lattice parameter of the perpendicular... 

Figure. 1. XRD patterns for a) amorphous Fe2oNigo b) crystalline a-Fe c) crystalline y-Ni d) crystalline Fe2oNigo e) crystalline Fe4oNi6o f) crystalline Fego Ni4o.

Whereas XRD patterns of the thin crystalline films provide information on the orientation and lattice distances perpendicular to the substrate, AFM has proven to be a powerful technique for obtaining structural information of thin-lilm surfaces of conjugated materials 195 j. AFM imaging of the surface of a thin (10 nm) annealed film of Ooct-OFV5 confirmed the domain structure of the annealed Ooct-... 

Figure 2. XRD pattern of an EMD sample (Chemetals). The diffractogram is taken with a Bruker AXS D5005 diffractometer using CuKa radiation and a scintillation counter. The step width is 0.02° with a constant counting time of 10 s / step.

It has been mentioned above that bir-nessite-type samples can show a wide variety of different XRD patterns. Mostly, the samples show only XRD peaks around 240 pm (20 37° for CuKa radiation) and 142 pm (2 ss 66°). These peaks correspond to the (1 0 0) and (110) reflections of the simple hexagonal setting of the S - Mn02 unit cell. Additionally, in some natural as well in synthetic materials the basal plane (0 0 l) reflections (001) and (0 0 2) do occur at about 700 pm (26 312°) and 350 pm (26 25°), respectively. 

A similar procedure was adopted for synthesis of nanoparticles of cellulose (CelNPs). The polysaccharide nanoparticles were derivatised under ambient conditions to obtain nanosized hydrophobic derivatives. The challenge here is to maintain the nanosize even after derivatisation due to which less vigorous conditions are preferred. A schematic synthesis of acetyl and isocyanate modified derivatives of starch nanoparticles (SNPs) is shown in scheme 3. The organic modification was confirmed from X-ray diffraction (XRD) pattern which revealed that A- style crystallinity of starch nanoparticles (SNPs) was destroyed and new peaks emerged on derivatisation. FT-IR spectra of acetylated derivatives however showed the presence of peak at 3400 cm- due to -OH stretching indicating that the substitution is not complete. 

The XRD pattern of the as-prepared ZnSe nanoparticles (Figure 3) exhibited predominantly wurtzite crystal structure with distinct diffraction peaks corresponding to the crystalline planes of hexagonal ZnSe and lattice constant of 0.397 nm, which was... 

Fig. 3. XRD patterns of (a) pure starch and (b) starch -capped ZnSe nanoparticles.

Fig. 2 shows XRD patterns and H2 TPR results for W-Sb-O with various Sb contents. The triclinic structure of WO3 shows three distinct peaks between 29 = 23° and 25°. As Sb content increases up to 0.6, the last two peaks diminish gradually with a new peak appearing at about 26 = 24°. As Sb content increases to 1 or higher, the XRD pattern abruptly changes again, which can be explained from SEM micrographs. 

Fig. 1 shows the XRD patterns of the TiOa particles prepared using different concentration of nitric acid(a) and TENOHfb). These particles are only dried at 105°C without any calcination. 

Fig. 1. XRD pattern of naaosized TiOj powders prepared at different HNOj concentration(a) and TENOH concentration(b) synthesized at 180t)(a) and 160 t (b), dried at lOSt).

Fig. 1. XRD patterns of Sn02-Zr02 catalysts with Sn/Zr molar ratio.

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