The present study was carried out to investigate the Pre and Post Monsoonal fluctuations in the water quality parameters of Upper Lake. Evaluation of physico-chemical parameters was carried out according to standard methods for the analysis of water as prescribed in APHA³ and NEERI¹⁵. Sampling was done for two years (2004 and 2005) during pre-monsoon and monsoon seasons. The aim of study was to examine the influence of seasonal variation on the physicochemical characteristics of water quality before and after rain. Water Samples were taken from Yatch Club site at the bank of Upper Lake. Better water quality was found in the Post-monsoon season than during Pre-monsoon season. Temperature, Nitrate, Conductivity and heavy metals are found higher in pre monsoon season. pH of water tends towards alkalinity. Turbidity, DO and phosphate are found increased in post monsoon season.

Some air stable mixed ligand complexes with VO(IV) and Zr(IV) ions are synthesized with physiologically active 4-amino-3-ethyl-5-mercapto-S-triazole as primary and carbon disulphide, pyridine and thiocyanate as secondary ligand. These were characterized by various physio-chemical methods. VO(IV) complex shows distorted octahedral and all ZrO(IV) complexes are octahedral geometry.

Some mixed ligand complexes of the type [M(MQTC)₂X₂] where M = Co(II), Ni(II) and Cu(II), MQTC = 3-methyl (N-O-Toludine)quinazolone thiosemicarbazone, X = Cl^-, Br^-, I^-, NO₃^- and ClO₄^-. The ligand as well as metal complexes were characterized by elemental analysis, IR spectra, electronic spectra, magnetic suceptibility and molar conductance study. The molar conductance measurements of the complexes in DMF corresponds to non electrolytic in nature. On the basis of above observations the ligand MQTC behaves as bidentate manner and coordination proposes through azomethine N and thione sulphur atoms of thiosemicarbazone moiety. The remaining coordination sites are occupied by negative ions such as Cl^-, Br^-, I^-, NO₃^- and ClO₄^-. The complexes were proposed to be octahedral in geometry on the basis of electronic and magnetic susceptibility value.

Mixed ligand complexes of Co(II), Ni(II) and Cu(II) have been synthesized with 2-phenyl [3- hydroxy ethyl)] 3-1 (4H) quinazoline-4- hydrazone (PHQH). The complexes have been formulated as [M(PHQH)₂X₂] M = Co(II), Ni(II) and Cu(II), X = NH₃, pyridine, a-picoline, b-picoline and g-picoline. The ligand PHQH and its metal complexes were characterized by elemental analysis, IR, electronic spectra, magnetic susceptibility and molar conductivity value. On the basis of above observations the ligand PHQH acts as neutral bidentate manner and coordination takes with amino N and azomethine nitrogen. The remaining coordination sites are occupied by neutral molecules such as, NH₃, pyridine, a-picoline, b-picoline and g-picoline. The ligand as well as metal complexes were screened for antifungal activity.

Five -coordinated mixed- ligands organometallic complexes of low - valent iridium(I)with triphenyl Phosphine (Pf₃)and 3-(4-Pyridyl)-triazoline - 5- thione (PytTH)and its 4- Phenyl substituted derivative (PPytTH)have been prepared and characterized on the basis of micro -analytical, magnetic moment and electronic and IR Spectral data. Trans -[IrCl(CX)(Pf₃)₂] (X= O/S) undergo Substitution with triazole ligands giving [Ir(CX)(Pf₃)₂ Ligand] in which deprotonation of imino group of hydrogen occurs and ligand acts as bidentate N, S-donor. Metal-ligand vibrations in far IR region have been located and tentatively assigned.

Co(II), Ni(II) and Cu(II) complexes have been synthesized with Schiff bases 2- (p-chlorophenyl) 4, 5- dimethyl (8H) pyrimido [4,5-d] pyrimidine hydrazone [CDPPH]. The complexes were characterized on the basis of elemental analysis, IR spectra, electronic spectra, magnetic susceptibility and molar conductance data. The analytical data of the complexes indicate 1:2 metal ligand stoichiometry of the type [M(CDPPH)₂X₂], where X = Cl^-, Br^-, I^-, NO₃^- and ClO₄^-. The ligand bahaves as neutral bidentate chelating agent and coordination takes place through azomethine N, amino N of pyridine ring. The remaining co-ordination sites are occupied by negative ions, Cl^-, Br^-, I^-, NO₃^- and ClO₄^-. The complexes were proposed to be octahedral geometry. The ligand as well as metal complexes were screened for antifungal activity.

The corrosion properties of zircon particulate reinforced aluminium 6061 metal matrix composites in different concentrations of hydrochloric acid and sodium chloride was studied by weight loss method. Composites were prepared by liquid melt metallurgy technique using vortex method. The percentage of reinforcement was varied from 3 to 7 wt% in steps of 2%. Specimens were designed according to ASTM standards and subjected to corrosion tests. The corrosion rates of matrix alloy and the composites were determined and compared with each other. The composite was found to be more corrosion resistant than matrix alloy. The decrease in the corrosion rates of composites when compared to that of matrix alloy is due to the passive layer formed in both the corrodents.

Two series of compounds (i) 2- substituted phenyl-10H-Pyridazin (6, 1-b) quinazoline-10-one (4a-g) and (ii) 6-substituted Phenyl tetrazolo (1, 5-b) pyridazine (5a-g) were synthesized. These compounds were evaluated for their hypotensive and anticonvulsant activities. These drugs showed the hypotensive activity ranging from 17.8 to 27.4% while standard drug minoxidil showed 27% reduction in blood pressure. All these compounds showed significant anticonvulsant activity when compared with phenytoin.

In this study which was carried out between January till September (2008). Cd, Mn, Cu, Fe, Pb, Ni and Zn content were determined in muscle and liver of Oreochromis niloticus caught from Wadi Hanifah Riyadh, Saudi Arabia. Among the heavy metals analyzed Cu, Pb, and Cd were below the detection limit. (<0.03). Heavy metal concentrations varied significantly depending on the type of the tissue and season. The highest metal concentrations were found in the liver, followed by muscle, and the high concentration of metal increased in summer, while were decreased in winter. The present study shows that precautions need to be taken in Wadi Hanifah stream in order to prevent heavy metal pollution that can occur in the future.

Key words : , , .

Kinetics of oxidation of mixture of glycine and nicotinic acid by chromic acid in presence of hydrochloric acid have been studied. The probable products are ammonia, carbon di oxide, formaldehyde and pyridine- N- oxide. The rate of oxidation decrease with increase in the concentration of hydrochloric acid. Ostwald isolation method is used for study the rate of the reaction. The rate of reaction with respect to [H⁺] is one. Kinetics of oxidation of mixture of glycine and nicotinic acid by chromic acid shows first order reaction. The kinetic parameters such as energy of activation, catalytic constant, temperature coefficient are calculated.