Bis(para-toluidinium), tetrachlorocuprate and bis(para-chloroanilinium)2 tetrachlorocuprate crystallize in a perovskite-related layer structure. The former crystallizes in an orthorhombic unit cell with a = 6.91 1 A, b = 7.052A and c = 33.182A. It undergoes a thermochromic first order phase transition from a yellow low temperature phase to a dark orange high temperature phase at T = 300 i. 3 K with a IO" thermal hysteresis. The latter compound undergoes two thermochromic transitions expressed by the 294 K 214Krelation.Orange Phase (I) -Yellow Phase (11) +Green Phase (111). Both compounds are ferromagnetic at low temperture with exchange interactions J / k = 17.5" and 20" for the two compounds respectively.

Polyvinyl Vinyl Chloride (PVC) multiwall carbon nanotubes (MWCNTs) nanocomposite flexible films were prepared using the solvent blend technique. Chloroform (CHCl3) and tetrahydrofuran ((CH2)4O) were used as solvents for MWCNTs and PVC, respectively. The effect of the solvents’ blend on electrical, optical and thermal properties of PVC/MWCNTs were investigated. The results of the Raman spectrum showed that all the characteristic bands of PVC polymer have a slight shift due to addition of MWCNTs. Electrical results showed that the nanocomposite samples with chloroform volume ratios of 10% and 25% had nearly the same conductivity. This is attributed to the formation of the MWCNTs network, which assisted in electrical conductivity. The I-V hysteresis curve decreases as the temperature increases and as it approaches the glass transition temperature. The non-isothermal kinetics analysis for PVC and PVC/MWCNTs were investigated by Thermogravimetry Analysis (TGA) using the model-free kinetic method. The non-isothermal measurements were carried out at five heating rates of 5 to 40∘C/min. The results show that the main decomposition process has constant apparent activation energies for all samples. The use of the bi-solvent method has improved the dispersion of untreated MWCNTs, and this has been reflected on the stability of both electrical and thermal properties.

Chromium doping effects on the structure and the magnetic properties of bismuth ferrite BiFe 1−x Cr x O 3 (x = 0-0.3) (BFC x O) polycrystalline samples are examined. The Perovskite-type oxide samples are synthesized by the conventional solid state reaction at a high pressure of 7 GPa and a temperature of 1273 K. The X-ray powder diffraction patterns at room temperature show that all the samples with x = 0.0-0.3 are described by the rhombohedral structure. In the meantime, it is revealed that the doping of Cr can induce noticeable lattice distortions in the doping samples, and the largest distortion is observed in the case x = 0.1. The magnetic hysteresis loops measured at room temperature exhibit week ferromagnetic behaviors of the samples and the magnetization is found to increase with the increase in Cr concentration. The temperaturedependent magnetization curves indicate antiferromagnetic features in samples. Moreover, Cr-doping tends to reduce the ordering temperature.

This study aims at developing magnetic materials through the combination of cobalt and iron oxide at the nanoscale for producing facile and environmentally friendly techniques to remove crude oil from water.