The ion exchange resin Amberlite IRA-400 in iodide and bromide form where equilibrated separately with the respective labeled iodide and bromide ion solution of different concen-trations varying from 0.005M to 0.100M ...The ion exchange resin Amberlite IRA-400 in iodide and bromide form where equilibrated separately with the respective labeled iodide and bromide ion solution of different concen-trations varying from 0.005M to 0.100M in the temperature range of 32.0 oC to 48.0 oC. The dis-tribution coefficient Kd values calculated for iodide and bromide ion exchange increases with rise in ionic concentration of the external solution, however with rise in temperature the Kd values calculated where found to decrease. Also the Kd values calculated where higher for iodide exchange than bromide exchange. Among the different alternative techniques available for obtaining the Kd values, the radio-active tracer technique used in the present ex-perimental work offers high detection sensitivity. It is expected that the distribution coefficient data obtained from such experimental work will significant in environmental impact assessment on the disposal of radioactive waste.展开更多
Instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques were used to analyze 18 elements (K, Mn, Na, Fe, Zn, Cu, Co, Br, Sm, Cl, La, Al, Cr, Ca Cd, Ni, Pb and Hg) in differe...Instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques were used to analyze 18 elements (K, Mn, Na, Fe, Zn, Cu, Co, Br, Sm, Cl, La, Al, Cr, Ca Cd, Ni, Pb and Hg) in different medici-nal plants often used in Indian Ayurvedic system. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activities were counted by γ-ray spectrometry using efficiency calibrated high resolution High Purity Germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the ele-ments under study. The elemental concentra-tion in different part of medicinal plants and their biological effects on human beings are discussed.展开更多
The selectivity behaviour of ion exchange resin Amberlite IR-120 for inorganic cations like sodium and potassium was predicted on the basis of thermodynamic data. The equilibrium constant K values calculated for uni-u...The selectivity behaviour of ion exchange resin Amberlite IR-120 for inorganic cations like sodium and potassium was predicted on the basis of thermodynamic data. The equilibrium constant K values calculated for uni-univalent ion exchange reaction systems were observed to increase with rise in temperature, indicating endothermic ion exchange reactions. From the K values calculated at different temperatures the enthalpy values were calculated. The low enthalpy and higher K values for K+ ion ex-change reaction indicates more affinity of the resin for potassium ions as compared to that for sodium ions also in the solution. The technique used in the present experimental work will be useful in understanding the selectivity behav-iour of different ion exchange resins for ions in the solution. Although the ionic selectivity data for the ion exchange resins is readily available in the literature, it is expected that the informa-tion obtained from the actual experimental trials will be more helpful. The technique used in the present experimental work when applied to dif-ferent ion exchange resins will help in there characterization.展开更多
文摘The ion exchange resin Amberlite IRA-400 in iodide and bromide form where equilibrated separately with the respective labeled iodide and bromide ion solution of different concen-trations varying from 0.005M to 0.100M in the temperature range of 32.0 oC to 48.0 oC. The dis-tribution coefficient Kd values calculated for iodide and bromide ion exchange increases with rise in ionic concentration of the external solution, however with rise in temperature the Kd values calculated where found to decrease. Also the Kd values calculated where higher for iodide exchange than bromide exchange. Among the different alternative techniques available for obtaining the Kd values, the radio-active tracer technique used in the present ex-perimental work offers high detection sensitivity. It is expected that the distribution coefficient data obtained from such experimental work will significant in environmental impact assessment on the disposal of radioactive waste.
文摘Instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques were used to analyze 18 elements (K, Mn, Na, Fe, Zn, Cu, Co, Br, Sm, Cl, La, Al, Cr, Ca Cd, Ni, Pb and Hg) in different medici-nal plants often used in Indian Ayurvedic system. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activities were counted by γ-ray spectrometry using efficiency calibrated high resolution High Purity Germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the ele-ments under study. The elemental concentra-tion in different part of medicinal plants and their biological effects on human beings are discussed.
文摘The selectivity behaviour of ion exchange resin Amberlite IR-120 for inorganic cations like sodium and potassium was predicted on the basis of thermodynamic data. The equilibrium constant K values calculated for uni-univalent ion exchange reaction systems were observed to increase with rise in temperature, indicating endothermic ion exchange reactions. From the K values calculated at different temperatures the enthalpy values were calculated. The low enthalpy and higher K values for K+ ion ex-change reaction indicates more affinity of the resin for potassium ions as compared to that for sodium ions also in the solution. The technique used in the present experimental work will be useful in understanding the selectivity behav-iour of different ion exchange resins for ions in the solution. Although the ionic selectivity data for the ion exchange resins is readily available in the literature, it is expected that the informa-tion obtained from the actual experimental trials will be more helpful. The technique used in the present experimental work when applied to dif-ferent ion exchange resins will help in there characterization.
