Phase X-ray diffraction pattern

Although compounds prepared by the method just described exhibited the desired single phase x-ray diffraction pattern, the... 

Cationic quaternary ammonium compounds such as distearyldimethylammonium-chloride (DSDMAC) used as a softener and as an antistatic, form hydrated particles in a dispersed phase having a similar structure to that of the multilayered liposomes or vesicles of phospholipids 77,79). This liposome-like structure could be made visible by electron microscopy using the freeze-fracture replica technique as shown by Okumura et al. 79). The concentric circles observed should be bimolecular lamellar layers with the sandwiched parts being the entrapped water. In addition, the longest spacings of the small angle X-ray diffraction pattern can be attributed to the inter-lamellar distances. These liposome structures are formed by the hydrated detergent not only in the gel state but also at relatively low concentrations. 

Some films containing deposited nickel together with copper were annealed at 500°C in order to ensure the homogenization of the alloys. After their cooling down to room temperature the X-ray diffraction patterns demonstrated phase segregation of the alloys similar to that described by Sachtler et al. (45). 

Fig. 12. X-ray diffraction pattern of a Ni75Cu25 alloy (a) completely transformed into its -hydride (0 NiCuH), (b) after a partial hydride decomposition, alloy peaks appearing, (c) after a complete hydride decomposition, arrows pointing to the rich in copper alloy phase desegregated from the initial alloy after a multiple hydrogen absorption-desorption treatment. The peaks had been revealed after the disappearance of the hydride peaks. After Palczewska and Majchrzak (48),...

Thermotropic liquid-crystalline properties of different metal alkanesulfonates are studied by microscopy and X-ray diffraction [59]. Sodium soaps show smectic polymorphism of smectic A and smectic B phases. Ammonium soaps only show smectic A phases but polymorphism in the crystalline state. Calcium soaps show columnar mesophases. In Figs. 32 and 33 some textures and x-ray diffraction patterns are depicted. 

FIG. 33 X-Ray Diffraction Patterns of Ammonium Dodecane 1-Sulfonate. 2-D (a) and 3-D plots (b) of oriented samples. Both pictures show the presence of a nonordered smectic phase, since the diffuse, weak, wide-angle diffraction indicates only an average distance between the molecules and the sharp, intense small angle reflections a very well defined layer distance. The reflections are perpendicular to each other, so the structure should correspond to an orthogonal smectic A type. The pictures were obtained using an x-1000 area detector from Siemens. 

In this group, the metals form compounds of the type Be M (M = Mg, Ca, Sr or Ba), MgjM (M = Ca, Sr or Ba) Mg4M or Mg23Mg (M = Sr or Ba) and MggM or Mg,7M2 (M = Sr or Ba) . These intermetallic phases are essentially identified and distinguished one from another by their x-ray diffraction patterns so their structures are included in this section. 

The Li-Zn phase diagram shows the presence of eight intermediate phases. Later x-ray diffraction results confirm the existence of five intermediate RT phases " . Polymorphism is shown by the three compounds shown in the Li-Cd phase system, and this has confused the interpretation of x-ray diffraction patterns ". 

Fig. 4.8 Powder X-ray diffraction pattern of pure single-phase Prb-IVand Rietveld refinement.

Fig. 4.10 Powder X-ray diffraction patterns for samples of phase-pure Prl2-IV annealed at different temperatures.

Figure 1 is a TEM photograph of the Cu (10wt%)/Al2O3 catalyst prepared by water-alcohol method, showing the dispersed state of copper and was confirmed the particle sizes from XRD data. Figure 2 is X-ray diffraction patterns of above-mention catalysts, was used to obtain information about phases and the particle size of prepared catalysts. Metal oxide is the active species in this reaction. Particle sizes were determined fix)m the width of the XRD peaks by the Debye-Scherrer equation. 

X-ray analysis of the various samples that were produced indicated that the system ZnO-ZnClj-HjO includes four crystalline phases, two of which, ZnO and ZnClj. l HjO, are essentially the starting materials. Sorrell also found the 4 1 5 phase, reported by Droit, with an identical X-ray powder diffraction pattern to that reported by Nowacki Silverman (1961, 1962), and a 1 1 2 phase. Since neither the 1 1 2 nor the 4 1 5 phase lost or gained weight on exposure to air at about 50% relative humidity and 22 °C and no changes developed in the X-ray diffraction pattern following this exposure, he concluded that the previously reported 1 1 1 phase cannot be formulated from mixtures of ZnO and aqueous ZnCl,. 

After some two hours, the X-ray diffraction pattern corresponded to either the 5 1 8 or the 3 1 8 phase warming of the sample had also occurred. Growth of the crystalline oxychloride phases continued rapidly up to about 15 hours, and more slowly thereafter, until after four days there was no trace of MgO in the diffraction pattern of the cement. 

Techniques for differentiating between amorphous and crystalline are (i) sharp melting point, (ii) sharp peaks in the solid state infrared fingerprint region, (iii) optical birefringence observed when solid is viewed in a phase contrast microscope and (iv) sharp peaks in the powder X-ray diffraction pattern. 

A room temperature powder X-ray diffraction pattern for Na8[GaSi04]6(C104)2 Sodalite with Si as an internal standard for phase identification in the reaction products has been studied. X-ray powder diffraction study confirms the cubic structure of Na8[GaSi04]6(C104)2 sodalite synthesized... 

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