The Knoevenagel condensation of aromatic aldehydes with barbituric acid, dimedone and malononitrile occurred in the presence of BF3/nano-γ-Al2O3 at room temperature in ethanol. This catalyst is characterized by powder X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and energy-disper...

Zeolite Phi is synthesized by two methods reported previously. Results from X-ray powder diffraction and scanning electron microscopy suggest that t h e materials are physical mixtures of chabazite and offretite; one sample has a small amount of phillipsite. The X-ray powder diffraction data from these samples, and those reported previously, are indexed and their unit-cell parameters compare we...

Following the seminal work of Von Dreele, powder X-ray diffraction studies on proteins are being established as a valuable complementary technique to single-crystal measurements. A wide range of small proteins have been found to give synchrotron powder diffraction profiles where the peak widths are essentially limited only by the instrumental resolution. The rich information contained in these ...

The very large expansion upon adsorption of liquids, up to 160% in cell volume, has been observed in the iron(iii) trans,trans muconate MIL-89 [(MIL = Material Institut Lavoisier]. The structure of lutidine-containing MIL-89 (lutidine = 2,6-dimethylpyridine) has been determined using X-ray powder diffraction and computer simulations. Finally, the consequences of adsorption of various polar and ...

This paper shows a simple procedure for the quantification of industrial and laboratory samples of Ammonium Sulphate-Nitrate fertilizers (ASN) based on a Rietveld fit from X-ray powder diffraction profiles. The Rietveld fit is performed by means of the structural models of the double salts 2NH4NO3·(NH4)2SO4 and 3NH4NO3·(NH4)2SO4, previously reported by the authors. The proposed method demonstra...

Abstract: Nano- size alumina particles have been synthesized by mechanical activation of a dry powder mixture of AlCl3 and CaO. Mechanical milling of the above raw materials with the conditions adopted in this study resulted in the formation of a mixture consisting of crystalline CaO and amorphous aluminum chlorides phases. There was no sign of chemical reaction occurring during milling stag...

The synthesis of Li(x)BC (x > 0.5) by high temperature Li deintercalation from LiBC is demonstrated by refinement of X-ray and neutron powder diffraction data--contrary to theoretical expectation no superconductivity above 2K is observed in these materials.

The Powder Diffraction File TM (PDF) is a comprehensive materials database that is the key source of reference powder diffraction data for identification and analysis of materials; from natural minerals and high-tech ceramics, to metals and alloys, and pharmaceuticals. New developments in X-ray analysis, and advances in scientific research, have dramatically influenced the range of data present...

Twelve different microcrystalline insulin formulations were investigated by X-ray powder diffraction and were shown to have very characteristic patterns. Three of the formulations crystallize in the same crystal system, but have structural differences in the N-terminal B-chain of the insulin molecule. This difference was efficiently detected in the powder patterns. The sensitivity of the method...