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Abstract  

A simple solvent extraction procedure for the efficient separation of the radioactive tracers95Nb and182Ta from each other in a mixture using di-(2-ethylhexyl)phosphoric acid (HDEHP) as extractant is described. Tantalum was found to be quantitatively extracted from an aqueous madium, which is 1.6N in HCl and 10−2 M in oxalic acid, with a HDEHP solution of 0.1 M concentration. Extractabilities of both niobium and tantalum in mineral acids like HCl, H2SO4 and HNO3 and in some organic acids like oxalic, citric, etc., in HDEHP under the experimental conditions were also studied. The reliability of the separation procedure was verified further by γ-ray spectrometry.

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Abstract  

A radiochemical charged particle activation procedure for the simultaneous production of carrier-free radioisotopes of more than one element in a single target and their subsequent separation through LLX has been demonstrated. The carrier free isotopes,95,96Nb,93,94,95,96,99mTc and94,95,97,103Ru formed through Mo(,pxn), Mo(,pxn) and Mo(,xn) nuclear reactions with 40 MeV -particle as detected by nondestructive -ray spectroscopy, have been effectively separated through LLX using TOA as an anionic extractant. Separation of the bulk matrix of molybdenum from the carrier free products has been monitored radiometrically using isotopic93,99mMo formed through the Mo(,xn) reaction, as radioindicators for the target element. Purity of the separated carrier free radionuclide has been verified by -ray spectrometry.

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Abstract  

The carrier-free radiotracers,52,56Mn,55,56,58Co and56,57Ni were produced simultaneously by accelerated -particle activation of iron. They were subsequently studied through LLX using the liquid cation exchanger, HDEHP, as an extractant. A considerable enrichment of individual carrier free radionuclides of manganese, cobalt and nickel was achieved. Production and verification of purity of the carrier-free radiotracers at different stages of their extraction were carried out by -ray spectroscopic studies.

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Abstract  

A radiochemical charged particle activation procedure has been developed for the production and separation of the carrier free radioisotopes,65Zn and66,67,68Ga. The carrier free radioisotopes produced by the irradiation of a pure copper foil with 50 MeV -particle beam through the nuclear reactions, (, pxn), (,pxn) and (,xn), have been quantitatively separated from the activated copper matrix from an aqueous hydrochloric acid and an alkaline solution using the liquid cation exchanger HDEHP, as an extractant. Detection of different radionuclides in the activated copper target and verification of their purity at different stages of their LLX separation have been performed by -ray spectrometric studies.

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Abstract  

Simultaneous production of carrier free89Zr and90,91m,92mNb through the (, pxn) and (,xn) nuclear reactions has been performed by -particle activation of Y2O3 target. The sequential separation of the produced radioisotopes from the bulk target matrix has been achieved through LLX using TOA as a liquid anion exchanger. Formation of the carrier free radionuclides in the target matrix and their purity in different stages of separation have been verified by -ray spectrometry.

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Abstract  

The k 0 based internal monostandard neutron activation analysis was used to analyze 41 ancient pottery samples from three major locations of Andhra Pradesh state, India, belonging to two different age groups namely Megalithic and Buddhist periods. Samples were irradiated with neutron flux obtained from CIRUS reactor and radioactive assay was carried out using a 40% relative efficiency HPGe detector coupled to 8 k MCA. Concentration ratios of 21 elements were calculated with respect to internal monostandard Sc. Absolute concentrations for six (three each from both Megalithic and Buddhist periods) representative samples along with a modern pottery were obtained for comparison. Elemental concentration ratios with respect to Sc were used for grouping of these archaeological samples. Preliminary grouping of these artifacts was done using La/Ce values, and the grouping was confirmed by statistical cluster analysis using eleven selected trace elements. The IAEA RM SL-3 sample was analysed for validation of the method, where in both concentration ratios and absolute concentrations were calculated.

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Abstract  

Ethylene dicysteine (EC) and ethyl cysteinate dimer (ECD) complexes of67Ga and111In were prepared and the complexation yield and radiochemical purity estimated by paper chromatography, paper electrophoresis and solvent extraction into chloroform.111In-EC was found to be anionic, whereas111In-ECD was neutral. EC complexes of67Ga and111In were stable upto 6 hours and expectedly less lipophilic than ECD complexes. ECD complexes of67Ga and111In were unstable in aqueous medium, but highly stable in chloroform. The utility of the work for stabilisation of products as organic extract and the possible role and limitation for the development of new68Ga radiopharmaceuticals and of bifunctional chelating agent (BCA) for111In are discussed.

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Abstract  

Carrier free101,105,106Rh,103,104,105,106,110,112Ag and104,105,107,109,111Cd radioisotopes were produced simultaneously by -particle irradiation of palladium target material in a variable energy cyclotron. The radioisotopes produced were extracted and separated from the activated target by LLX using HDEHP as liquid cation exchanger. With the help of -ray spectrometry the presence of several radioisotopes in the activated target matrix and their purity at each step of the separation was confirmed.

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Abstract  

Relatively longer liver technetium tracers such as95mTc (61 d) are useful for the development, evaluation and comparison of new technetium complexes for eventual development of99mTc radiopharmaceuticals. The feasibility of producing96Tc (4.35 d) and95mTc (61 d) was studied by the alpha bombardment of pure Nb targets (93Nb-100%).96Tc was obtained in a yield of 30 Ci/Ah using 16 MeV alphas, but it contained significant activity of95Tc (20 h) Relatively pure96Tc and95mTc was produced in yields of 18 Ci/Ah and about 1 Ci/Ah respectively with alphas of suitable energy and after allowing for suitable cooling periods after the end of bombardment (EOB).

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