Search Results

You are looking at 1 - 4 of 4 items for :

  • Author or Editor: Z. Khan x
  • Chemistry and Chemical Engineering x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

A rapid method for the solvent extraction of Hg(II) into chloroform has been developed, employing thioethylacetoacetate (HETAcAc) as a extracting agent. The extraction of Hg(II) was better than 99% over the pH range 0.3 to 7.3. The extraction equilibrium was reached within 2 min. The effect of various parameters such as anions and cations, solvent effect, etc., on the extraction coefficient has been studied. The stoichiometry metal: reagent was determined by the method of substoichiometric extraction and was found to be 14.

Restricted access

Abstract  

A method has been developed for rapid and selective extraction of Au/III/ with ethyl thioacetoacetate /HETAcAc/ into chloroform at pH 4. The effect of various parameters on the extraction coefficient values have been studied. The stoichiometry of the extracted species 13 was obtained by the slope ratio method and by the method of substoichiometric extraction.

Restricted access

Abstract  

The method described here involves the irradiation of biological samples and a g quantity of standard with thermal neutrons at the self-serve position in the CIRUS reactor, followed by dissolution of the sample and standard in the presence of milligram amounts of carrier. Both the sample and the standard are subjected to substoichiometric extraction under controlled experimental conditions with ethyl thioacetoacetate into chloroform. An aliquot of the organic phase is counted on a -spectrometer. The concentration of Hg in various biological samples and the accuracy, precision, and sensitivity of the method are discussed.

Restricted access

Abstract  

Specific activity of natural radionuclides; 226Ra, 232Th and 40K were measured in the agricultural soil of eastern salt range of Pakistan using gamma ray spectrometry. The soil samples were collected within the ploughing region (up to 12 cm depth) and processed before analysis. The average specific activities of different radionuclides in the dry mass of soil samples were: 40K, (666 Bq/kg), 226Ra (51 Bq/kg), and 232Th (59 Bq/kg). The average outdoor terrestrial absorbed dose rate in air from gamma radiation one meter above ground surface was found to be 93 nGy/h.

Restricted access