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Abstract  

Ground water samples obtained from West Bengal, India were analyzed for total arsenic and its inorganic species contents by instrumental neutron activation analysis (INAA). Two anion exchange separation methods using Dowex 1X8 in chloride and acetate forms were standardized for the speciation of As(III) and As(V) using radiotracers. The method by Dowex 1X8 in the acetate form was validated using synthetic mixtures of As(III) and As(V), and applied to water samples; the species concentrations were determined by INAA. The accuracy of the INAA method was evaluated by analyzing the NRCC CRM DORM-2 for total arsenic.

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Abstract  

An internal mono-standard method has been proposed for multi element analysis. This method gives the relative concentration of the elements in a sample of non-standard shape and size. It utilizes an in-situ relative efficiency calibration and hence, does not need the cumbersome procedures, otherwise required to correct for -attenuation in the sample. To validate this method, the relative concentration of elements in IAEA RM's SL-3 and Soil-7 were analyzed with sample amounts ranging from a few milligrams to grams. The samples were counted in different non-specific geometries. The results are in good agreement with the recommended values, suggesting that this methodology could be applied for the analysis of samples of non-standard size and shape, and in principle, for the analysis of large samples.

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Abstract  

Traditional Indian medicinal herbs, used for strengthening the body immune system, are rich source of many essential nutrient elements in bioavailable form. Instrumental neutron activation analysis (INAA) employing short (5 minutes) and long (14 hours and 3 days) reactor irradiation followed by high resolution gamma-ray spectrometry has been used for the determination of Al, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cu, Eu, Fe, K, La, Mg, Mn, Na, P, Rb, Sb, Sc, Sm, Th, V and Zn in 15 medicinal herbs commonly used in Indian household for treatment of various ailments. viz. C. rhombifolia (Amaltas), W. somnifera (Ashwagandha), P. corylifolia (Bakuchi), T. cordifolia (Guduchi), M. fragrans (Jaiphal), N. jatamansi (Jatamansi), A. paniculata (Kalmegh), H. anticlysentrica (Kutaj), T. chebula (Laghu Haritaki), S. racemosa (Lodhra), A. indica (Neem), V. negundo (Nirgundi), H. indicus (Sariva), A. calamus (Vach) and E. ribes (Vidang). Several of herbs are enriched in Ca, Co, Cu, Mg, P, Fe, Mn and Zn, which play a vital role in biochemical and enzymatic processes. Jatamansi, often used as antibacterial, antipyretic and heart tonic is specially enriched in Co, Cr, Cu, Na, Mn, Fe, Rb and Zn. Also Guduchi and Laghu Haritaki are enriched in Ca and Mg, respectively. An attempt has been made to correlate elemental contents with the therapeutic importance of various herbs. Also our results for the participation in an Intercomparison Study of renewal of Pine Needles (SRM-1575a) from NIST, USA are presented.

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Abstract  

Brahmi (Bacopa monnieri) leaves, known as nervine tonic in Ayurveda, and its aqueous (BA), methanolic (BM) and aqueous–methanolic (BAM) extracts were analyzed for 7 minor (Al, Fe, Na, K, Ca, P, Cl) and 18 trace (As, Au, Ba, Br, Co, Cr, Cu, Hf, Hg, La, Mn, Rb, Se, Sm, Sr, Th, V, Zn) elements by INAA. BAM extract showed maximum contents of Na, K, Cl and significant amounts of Mn, Co, Zn. It was also found as effective scavenger of DPPH radicals with 33.5% total phenolic content, highest γ-ray radioprotective effect and higher anti lipid peroxidation activity.

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Abstract  

Cumulative yields of short-lived ruthenium isotopes in the thermal neutron induced fission of235U,235U and239Pu have been determined using a fast radiochemical separation technique followed by gamma spectrometry. The cumulative yields of107Ru and103Ru in233U (nth, f) and107Ru and109Ru in239Pu (nth, f) are determined for the first time. The measured cumulative yields are converted to chain yields assuming normal charge distribution systematics for comparison with the literature data on chain yields.

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Abstract  

Cumulative yields of short-lived xenon isotopes137,138,139Xe have been determined in the spontaneous fission of252Cf, using a fast radiochemical separation method followed by gamma spectrometry. Xenon-137 yield is reported for the first time. The measured cumulative yields are converted to chain yields assuming normal charge distribution systematics for comparision with the literature data.

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Abstract  

For the determination of phosphorus in different matrices, the derivative neutron activation analysis is especially applicable to aqueous samples, since the conventional neutron activation analysis is not useful for the determination of phosphorus. Phosphorus when reacted with ammonium molybdate 4 hydrate and ammonium metavanadate forms molybdo vanado phosphoric acid. This complex is preconcentrated by extracting into methyl isobutyl ketone. The organic phase containing the molybdo vanado phosphoric acid is neutron activated and the phosphorus is determined through the activation product of 52V. Preparation of this complex, its stoichiometry, application to trace level determination of phosphorus and improved detection limit are discussed. This method was applied for the analysis of industrial effluent samples.

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Abstract  

Four plant parts (leaves, roots, fruits and seeds) of twenty samples of sixteen antidiabetic herbs including three commercially marketed capsules have been analyzed for 6 minor (Na, K, Ca, Cl, Mg, and P) and 21 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sm, Th, V and Zn) elements by instrumental neutron activation analysis (INAA). Further, Ni, Cd and Pb contents were determined by AAS. Elemental data were validated by simultaneously analyzing reference material (RM), MPH-2 Mixed Polish Herbs. Several elements such as Cr and V (1–2 μg/g), Rb (10–40 μg/g), Cs (80–300 ng/g), Se (∼100 ng/g) and Zn (25–60 μg/g) play an important role in diabetes mellitus. Interelemental linear correlations have been observed for Cu vs. Zn (r = 0.89) and Rb vs. Cs (r = 0.87). K/P ratio varies in a narrow range with a mean value of 6.2 ± 1.4. Toxic elements As and Hg were found in <1 μg/g whereas Cd and Pb were in ∼5 μg/g and <10 μg/g, respectively.

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Abstract  

A summary of k 0-based R&D work on neutron activation analysis (NAA), internal mono standard NAA (IM-NAA) and prompt gamma-ray NAA (PGNAA) is presented. The k 0-based NAA was standardized by characterizing irradiation sites of research reactors, validated using reference materials and applied to samples of different origin. Recently IM-NAA method was developed, validated for small and large size samples and applied for the analysis of large size as well as non-standard geometry samples. Studies on PGNAA included characterization of neutron beam, determinations of detection efficiency and prompt k 0-factors, and analytical applications.

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Abstract  

An alternative reaction route for the production of111In from rhodium target bombarded with a12C beam has been developed. Sulfate fusion was adapted for dissolution of the irradiated rhodium metal target. Indium was coprecipitated with La(OH)3 and purified by solvent extraction of the InBr3 complex into di-isopropyl ether and back extraction in 6M HCl. The chemical yield of the separation, determined using105Rh as tracer, was found to be above 90%. The radionuclidic purity of the separated111In satisfies the requirement prescribed for radiopharmaceutical preparations. The radioactivity yield achieved using this route was about 0.2 MBq/μAh.

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