Quantitative phase analysis of anhydrous clinker Portland using Rietveld method

Modern cements are complex materials with well-defined compositions that reach to high and consistent results. Automated techniques such as Rietveld analysis lead to provide an understanding of the composition and polymorphism of cement phases that could lead to control of the clinkering conditions to optimize characteristics and consequently quality product. For the characterization of cements used in the construction sector, Rietveld method has significant benefits over other analytical techniques. The precise information about phase assemblage and polymorphism lets monitoring the hydration behavior of binder materials. The objective of this paper is to report the quantitative Rietveld phase analyzes for three industrial clinkers, to review the most recent quantitative X-ray powder diffraction studies on anhydrous cement and to discuss the influence of the different parameters elaborated in the Rietveld method.

Synthesis and biological evaluation of novel isoxazole derivatives from acridone

The present study was carried out in an attempt to synthesize a new class of potential antibacterial agents. In this context, novel isoxazoles were synthesized and evaluated for their potential antibacterial behavior against four pathogenic bacterial strains. The synthesized compounds exhibited moderate-to-good antibacterial activity against these strains. The highest antibacterial activity was observed against the Escherichia coli strains, particularly for compounds 4a and 4e with phenyl and para-nitrophenyl groups on the isoxazole-acridone skeleton; they showed promising minimum inhibitory concentration values of 16.88 and 19.01 μg/ml, respectively, compared with the standard drug chloramphenicol (22.41 µg/ml). The synthesized compounds were subjected to in silico docking studies to understand the mode of their interactions with the DNA topoisomerase complex (PDB ID: 3FV5) of E. coli. The molecular docking results showed that compounds 4a-l occupy the active site of DNA topoisomerase (PDB ID: 3FV5), stabilized via hydrogen bonding and hydrophobic interactions, which may be the reason behind their interesting in vitro antibacterial activity.

A highly turn-on fluorescent CHEF-type chemosensor for selective detection of Cu2+ in aqueous media

An efficient "turn on" fluorescence chemosensor Schiff base LH based on the combination of 2-Hydroxy-5-(p-tolyldiazenyl)benzaldehyde and N-(3-Aminopropyl)imidazole was prepared and characterized then evaluated for its selective fluorescent sensing of Cu²⁺ amongst other metal ions. The CN isomerization inhibition process induced by the Cu²⁺ binding warrants the chelation-induced enhanced fluorescence (CHEF) effect. In addition, the detection limit sensing of LH for Cu²⁺ was found to be 1.8 × 10^-6 M that is below the WHO recommendation level (20 μM) for drinking water.

2-((E)-{[3-(1H-Imidazol-1-yl)propyl]imino}methyl)-4-[(E)-(4-methylphenyl)diazenyl]phenol

In the title compound, C20H21N5O, the dihedral angles between the central phenol ring and pendant toluyl and imidazole rings are 3.20 (16) and 81.44 (14)°, respectively; the dihedral angle between the pendant rings is 84.39 (16)°. An intramolecular O—H...N hydrogen bond occurs. A Hirshfeld fingerprint analysis indicates that H...H contacts account for 48.6% of the surface.

2-((E)-{[3-(1H-Imidazol-1-yl)propyl]imino}methyl)-4-[(E)-(2-methylphenyl)diazenyl]phenol

In the title compound, C20H21N5O, an intramolecular O—H...N hydrogen bond forms between the –OH substituent of the phenol ring and the adjacent iminomethyl N atom, enclosing anS6 ring. The dihedral angles between the imidazole ring and the methylphenyl and phenol rings are 86.93 (14) and 88.00 (13)°, respectively, while that between the methylphenyl and phenol rings is 2.18 (12)°.