The investigation of the phase diagram of the binary system of Bi2O3-Sb2O3

The phase diagram of the binary system of bismuth and antimony sesquioxides were investigated in the air atmosphere in the mole fractions of Bi2O3 between 0.000 and 0.500. Three different phase regions that were dependent on the furnace temperature and heating period were obtained by the solid state reactions. In the first region, a heterogeneous mixture that contained orthorhombic Sb2O4 and monoclinic BiSbO4 phases occurred in the temperature range between 700 and 1100 degrees C. In the second region, the heterogeneous mixture transformed to a homogeneous solid solution that was characterised by a monoclinic crystal structure (BiSbO4 type). Fusion of the homogeneous solid solution which decomposed with volatilisation of Sb2O3 took place in the third region

Synthesis and Characterization of Novel Thiourea Derivatives and their Nickel and Copper Complexes

New benzoyl thiourea derivatives and their nickel and copper complexes were synthesized. The structure of the synthesized compounds were confirmed by elemental analysis, FT-IR, and H-1 NMR techniques. Four of the synthesized compounds are analyzed by X-ray single crystal diffraction technique. Whereas N,N-dimethyl-N'-(4-fluorobenzoyl) thiourea, N, N-diethyl-N'-(4-fluorobenzoyl)thiourea, and N,N-di-n-butyl-N'-(4-fluorobenzoyl)thiourea crystallize in the monoclinic system, bis(N,N-di-n-propyl-N'-(4-fluorobenzoyl)thioureato) nickel(II) complex crystallizes in the triclinic system. These ligandmolecules formdimers through strong intermolecular hydrogen bonds such as N-H center dot center dot center dot S, C-H center dot center dot center dot, and N-H center dot center dot center dot O. Moreover, there are different types of intramolecular interactions in the crystal structures. Bis(N,N-dimethyl-N'-(4-fluorobenzoyl)thioureato) nickel(II) complex has a nearly square-planar coordination. The distance of nickel atom from the best plane through the coordination sphere is 0.029 angstrom

Separation and preconcentration of palladium using benzoylthiourea immobilized on a cationic surfactant coated silica gel

A method for separation and preconcentration of trace levels of palladium on silica-cetyltrimethyl ammonium bromide coated with N,N-diphenyl-N'-(4-bromobenzoyl)thiourea was reported. The effects of parameters such as pH, amount of silica, amount of ligand, flow rate, type and concentration of the stripping agent were investigated. Sorbed ions were quantitatively eluted using 4 mL of 0.2 mol L-1 thiourea. The preconcentration factors of 31.3 to 313 are easily achievable. The relative standard deviation of the method was <+/- 5.85% for 10 replicate determinations of 0.002 to 1.0 mu g mL(-1) and the detection limit was 0.3 mu g L-1. The applicability of the developed admicelle sorbent was investigated using synthetic samples and real samples such as standard reference material 2709 (San Joaquin Soil) and 2711 (Montana Soil)