X-ray studies, spectral characterization and thermal behaviour of a two-dimensional Zinc Phosphate templated by Tris (2-aminoethyl) amine [C6H21N4][Zn6(P04)3 (Hp04)3). H20

A two-dimensional (2D) layered zinc phosphate hydrate [C6H21N4] [Zn6 (P04)3(HP04)3]. H20, I, was synthesized by reacting Zn2+ ions with tris-(2-aminoethyl) amine phosphate [C6H21N4][P04].5H20. The compound was characterized by powder x-ray diffraction analysis, energy dispersive analysis by x-ray and infrared spectroscopy. The thermal behaviour of compound I was studied under flowing nitrogen and the structure determined by single crystal x-ray crystallography. Compound I crystallizes in the orthorhombic space group Pna2(No. 33), a = 18.785(2), b = 8.2783(7), c = 18. 747(2)Ǻ, volume = 2915.4(4) Å3, z = 4. The structure consists of a network of Zn04, P04 and HP04 tetrahedra which are connected to form a layer with interlamelar region occupied by the protonated amine and water molecules. Keywords: Metal phosphates, open-framework solids, amine phosphates route, layered structureGlobal Journal or Pure and Applied Sciences Vol. 14 (4) 2008: pp. 389-39

Mixed-Ligand Complexes Of Nickel (II) With 2-Acetylpyridine Thiosemicarbazone And Some N/S Monodentate Ligands: Synthesis, Structural Characterization And Biological Activity

The preparation and spectral properties of five nickel (II) mixed-ligands complexes (Ni [2-Actsc.Y]CI2), derived from 2-acetylpyridinethiosermicarbazones and some nitrogen/sulphur monodentate ligands such as thiophene, ammonia, picoline, pyridine and aniline are described. The complexes have been characterized on the basis of 1H and 13C-NMR, IR and electronic spectra. These revealed the primary ligand to be a tridentate thiosemicarbazone that coordinate in a square planar conformation to nickel (II) via azomethine N, pyridyl N and thiolate S atoms and a monodentate donor molecuole. The antimicrobial activities of these mixed-ligands complexes were investigated. Nickel (II) mixed-ligands complexes derived from 2-acetylpyridinethiosemicarbazones and aniline or ammonia seem to be most efficient inhibitors among these tested compounds. Keywords: mixed-ligands complexes, square planar geometry, thiosemicarbazones, electronic spectra, biological activity.Global Journal or Pure and Applied Sciences Vol. 14 (4) 2008: pp. 411-41

A study on the significance of lithology in groundwater quality of Madurai district, Tamil Nadu (India)

The groundwater occurs in hard rock aquifers, which is more predominant in India. It is more common in the southern peninsula especially Tamil Nadu. Madurai district is located in the central part of Tamil Nadu, underlain predominantly by crystalline formations and alluvium along the river course. The study area being a hard rock terrain, the groundwater is stored in cracks, fissures, joints, etc., and hence the quantity is lesser. The frequent failure of monsoon also aggravates the scarcity of this commodity. In this scenario, the quality and hydrogeochemistry of the available quantum of water plays a significant role for the determination of its utility and in tracing out the hydrogeochemical evaluation. Fifty-four groundwater samples were collected representing the entire study area. The samples collected were representative covering all the major litho units of the study area (charnockite -21, fissile hornblende biotite gneiss-21, granite-4, quartzite-3, and 5 samples from flood plain alluvium). The samples collected were analyzed for major ions and were classified for different purposes like drinking, domestic, and agriculture, with respect to lithology.The comparison of the groundwater samples with the drinking water standards shows that few samples fall above the drinking water limit irrespective of lithology. The samples were classified with sodium absorption ratio, electrical conductivity, residual sodium carbonate, sodium percentage (Na %), Kellys ratio, and magnesium hazard, and permeability index for irrigation purpose found that most of the samples were suitable for irrigation purpose irrespective of lithology. Total hardness and corrosivity index were studied for the domestic purpose and found that the samples of the granitic terrain are safe. Apart from this, index of base exchange, Schoellers water type, Stuyfzands classification were attempted along with Gibbs plot to determine the major geochemical activity of the region. The study reveals that the samples collected from granitic and quartzitic terrains are comparatively better for the domestic and drinking purpose due to the presence of resistant minerals to weathering