VOLUME 9, NO3, SEPT 1987

THERMOGRAVIMETRIC AND GAS CHROMATOGRAPHIC STUDIES OF COPPER (II) AND NICKEL (ii) CHELATES OF MESO AND DL-BIS-(ISOVALERYLACETONE) STILBENEDIIMINE

Copper (II) and nicke (II) chelates of two tetradentate Schiff bases bis (isovalerylacetone) meso-stilbendiimine(meso-SiA2) and bis (isovaleryl-acetone)dl-stillbendiimineDl-SiA2) have been prepared and characterized using IR, NMR and mass spectroscopic techniques. The metal complexes have been assessed spectrophotometrically and their potentialities as analytical reagents have been evaluated. TGA, DTA and DSC of these complexes indicate that the metal complexes are sufficiently volatile and thermally stable at high temperature. The metal complexes can be gas chromatographed on OV 101, 3% on chromosorb 80-100 mesh size. Detection limit, calibration range and separation of dl and meso geometrical isomers are reported. The nickel chelates show greater sensitivity and low detection limits than the corresponding copper complexes at ng levelsread more

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M Y KHUHAWAR ,A G.M VASANDANI ,

SPECTROPHOTOMETRIC STUDIES ON SOME TRIPHENYLFORMAZANS. MEDIUM EFFECT ON THEIR ACID DISSOCIATION CONSTANTS

The acid dissociation constants of some triphenylformazans are investigated spectrophotometrically. The absorption spectra are recorded in solutions of varying pH-values, the spectra indicate the existence of two equilibria in solutions for (Ia-Id) and one equilibrium for (Ie and If). The effect investigated and the results are correlated to solvent effect. read more

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ZAKARIA FAHIM HANNA ,AIDA LOTFY ELANSARY ,YOUSRY MOUSTAFA ISSA ,

THE PORESTRUCTURE AND TEXTURE OF A FLUKA CHROMATOGRAPHIC ALUMINA GEL

The porous nature of Fluka Chromatograpic alumina gel 5016 A, has been investigated by adsorption/condensation process and electron microscopy. The gel is very porous having 63% porosity. Its free water content at 150oC was found to be 2.28% and bound water content at 1000oC was 3.66%. The total pore volume as determined by fluid displacement method is 0.497 cm3 g-1. Its specific surface area as determined by water vapour adsorption is 236 m2 g-1. The greater portion of the surface area and pore volume occurs in small and transitional pores, with average pore radii (hydraulic) of 21Ao. Heat treatment does not harm the physical structure of the system if the temperature is below 800oC. The surface area and pore volume are lower in comparision with the silica gel (383 m2g-1 and 0.62 cm3g-1) investigated earlier.  read more

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M KHAN ,M AFZAL ,

A NEW METHOD FOR THE DETERMINATION OF IODIDE VIA ANDREW'S REACTION STUDY WITH HEXAMMINECOBALT (III) TRICARBONATOCOBALTATE (III) AS VOLUMETRIC OXIDIMETRIC TITRANT

Andrew's reaction for the determination of iodide through the use of hexaminecobalt (III) tricarbonatocobaltate (III) as redox analytical volumetric titrant, has been studied. The reaction between iodide and Co3+ proceeds quantitatively in 0.5N H2SO4 and 5N HCl. Effects of chloride, bromide and nitrate as interfering radicals have also been studied separately and collectively on this determination. In either of the cases, the tolerance of foreign ions is quite high. Therefore, the method standardized is recommended for routine use in the determination of iodide. read more

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AZRA IMTIAZ ,MUHAMMAD HANIF ,ISHRAT IJAZ ,NAZ SHAHEEN ,

MICRODETERMINATION OF BARIUM IN FORMATION WATER BY ATOMIC ABSORPTION SPECTROPHOTOMETRY USING MATRIX MATCHING PROCEDURE

An improved method is described for the determination of barium occurring at tract levels in water associated with oil deposits in natural formation water. Better results were obtained by using matrix matching procedure than the standard addition method. Effect of high concentrations of calcium, strontium, potassium and sodium on barium absorbance have also been investigated. read more

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R MAHMOOD ,M. I. FAROOQUI ,J ANWAR ,

ESTIMATION OF MERCURY IN VARIOUS LOCAL FISH SPECIES AND RELEVANT WATER

Employing the flameless atomic absorption technique a method of general utility is proposed for the estimation of mercury content in fish. The method is based on the reduction of organic/inorganic mercury to elemental mercury using tin(II) chloride as the reductant. Marine and fresh water whole fish samples (wet weight 2-3 kg) of the following common species: Salmon, mallie, mashir, bangha and pamphlet are analysed. The estimated mercury content of these fish is examined in relation to that of the relevant water. A linear regression analysis of the data indicates the potential use of fish as an indicator of a local mercury pollution source.read more

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S A HUSSAIN ,M SALEEM ,M AHMED ,M JAFFAR ,

SPECIATION OF Cu AND Cr IN THE AQUEOUS ENVIRONMENT BY SPECTROSCOPIC AND VOLTOMMETRIC TECHNIQUES

A study of the speciation of Cu and Cr in the aqueous environment of Cork is outlined. A comparison is made of spectroscopic and voltammetric techniques for the determination of Cu and Cr in water sample, and the meaning of the results are discussed. read more

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M RASUL JAN ,W FRANKLIN SYMTH ,

A VOLTAMETRIC STUDY OF INORGANIC SELENIUM AND SOME ORGANOSELENIUM COMPOUNDS AT THE HANGING MERCURY DROP ELECTRODE AND ITS ANALYTICAL APPLICATIONS

 In this paper, the differential pulse voltametric behaviour and resulting analytical applications of inorganic and different organoselenium compounds were investigated. Limits of detection and quantitation have been calculated for the differential pulse voltametric determination of the organoselenium compounds. Lastly in this paper high performance liquid chromatographic studies with an electrochemical detector for the estimation of organoselenium compounds is also investigated read more

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WILLIAM FRANKLIN SYMTH ,M RASUL JAN ,IKRAMUL HAQ ,

DETECTION AND ESTIMATION OF LEAD IN CURCUMA LONGA BULBS (TURMERIC) BY ATOMIC ABSORPTION SPECTROPHOTOMETRY

Lead has been detected and estimated in turmeric by Atomic Absorption spectrophotometry, The solutions for analysis were prepared by sulphated-ash method and the absorptions were measured against standard solutions of method and the absorptions were measured against standard solutions of lead in a concentration of 20 ug/ml. The pure sample of curcuma longa bulbs were analysed for lead contents in the inner portion (matrix) and outer portion (cuticle) of the roots. The so called adulterated samples in which lead contents are very high were purchased from the market. read more

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AZHAR M SYED ,M QADIRUDDIN ,ATAULLAH KHAN ,

REACTIONS OF UNSATURATED COMPOUNDS. IV "OXIDATION OF SOME TETRA-ARYL ALIPHATIC OLEFINS BY CHROMIUM TRIOXIDE"

 The oxidation of 1,1,3,3-tetraphenyl-2-methyl,1,1-di-p-tolyl-3,3-diphenyl-2-methyl1,1-dibenzyl-3,3-diphenyl-2-methyl-2-methyl1,1,3,3-tetraphenyl and 1,1-di-p-tolyl-3,3-diphenyl propenes by chromium trioxide-acetic anhydride gives the corresponding epoxide with fission products. Chromic acid in aqueous sulphuric acid brings about oxidative fission of the double bond without any rearrangement. The isolation of terephthalic acid and p-toluic acid from oxidation of 1,1-di-p-tolyl-2-methyl-3,3-diphenyl and 1,1-di-p-tolyl-3,3-diphenyl propenes was discussed. The action of perbenzoic acid on these tetra-aryl olefins was also studied. read more

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M E SHABAN ,G E.M MOUSSA ,M R SALEM ,E I NAGDY ,