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  • Author or Editor: A. Gupta x
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Abstract  

Sorption of Li+, Cs+ and Sr2+ on hydrous titanium oxide and magnetite as a function of pH in the presence and absence of -rays has been studied. pH-titrations of the irradiated hydrous oxides have also been carried out. It has been shown that the sorption characteristics of these oxides are not altered by -irradiation and the uptake of metal ions is governed by the equilibrium pH of the solution. Certain physical changes observed on irradiating of the hydrous oxide samples in water are discussed.

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Abstract  

The extraction behavior of uranium, thorium and lanthanides, represented by cerium and ytterbium, by Cyanex-923 has been investigated. The effect of different variables like the concentration of acids, metal ion and extractant, nature of diluent and temperature has been studied. A composition for the extracted U(VI) and Th(IV) species has been proposed. Based on the partition data some important binary and ternary separations involving the aforesaid metal ions have been achieved. The proposed procedure has been applied for the recovery of uranium, thorium and lanthanide fraction from monazite sand. The stability and regeneration capacity of the extractant have been evaluated.

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Summary

An online-hyphenated high-performance liquid chromatography-photodiode array-mass spectrometry (HPLC-PDA-MS) analytical method was developed for the simultaneous determination of six lignans of therapeutic importance in four Phyllanthus spp. (P. amarus, P. maderaspatensis, P. urinaria, and P. virgatus). HPLC with monolithic reverse phase silica column (4.6 × 100 mm) and simple isocratic elution of methanol-water mixed with dioxane facilitated the separation of lignans of diverse nature such as diarylbutyrolactone, tetrahydrofuran, isomeric aryltetralin, and diarylbutane type for quantitative analysis. Targeted lignans viz. heliobuphthalmin lactone (1), virgatusin (2), hypophyllanthin (3), phyllanthin (4), nirtetralin (5), and niranthin (6) were confirmed unambiguously in four Phyllanthus species by their abundant molecular adduct ions, retention time, UV, and mass spectra as compared with those of reference compounds. Advantages and limitations of both detection techniques for qualitative (fingerprinting) and quantitative analysis of the above mentioned lignans in four Phyllanthus spp. are discussed. The method was validated following international guidelines. The described method can be utilized for assays and stability tests of P. amarus extracts as well as traditional Indian medicine based on Phyllanthus herb.

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Abstract  

This paper deals with the studies on decontaminations of spent ion exchange resin used for purification of plutonium in PUREX process stream. Studies were carried out to optimize the chemical procedure for removal of plutonium and fission products activities form spent Ion Exchange resin. Different metal complexing reagents were tested for leaching out of radionuclides entrapped in irradiated spent ion exchange resin. The experimental results indicate that 0.01 M NaF solution was found the most suitable for removal of plutonium. The mixture of Na2CO3 and sodium salt of EDTA solution was found to be better for decontamination of spent ion exchange resin from beta and gamma activities. Optimized mixture of 0.5 M Na2CO3 and 0.1 M sodium salt of EDTA solution was found to be the most effective for fission product activities removal. After successive multiple contacts using these suitable reagents, the Pu and fission product activities in spent ion exchange resin were brought down to a minimum possible level, making it quite suitable for its long term storage.

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A high-performance thin-layer chromatographic (HPTLC) method has been established for simple and rapid quantification of two secoiridoids, swertiamarin and amarogentin, in two Swertia species. HPTLC of secoiridoids was performed on precoated silica 60 F 254 plates with EtOAc-MeOH-H 2 O, 77 + 8 + 8 ( v/v ), as mobile phase. Densitometric determination of the secoiridoids was performed at λ = 235 nm in reflectance/absorbance mode. The method was validated for precision, repeatability, and accuracy. Average recovery of amarogentin and swertiamarin was 94.5 and 96.5%, respectively, showing that the reproducibility of the method was excellent. The method is simple, precise, specific, sensitive, and accurate and can be used for routine quality control of raw materials and herbal formulations.

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Abstract

Schiff base metal complexes derived from 2-thiophenecarboxylidine-4-anisidine, 3,4-dihydroxy-5-nitrobenzylidine-2-amino-5-methylthiazole and 3,4-dihydroxy-5-nitrobenzylidine-4-chloroaniline have been synthesized and characterized by elemental analysis, IR, UV–Vis, molar conductance and thermal analyses. The complexes are coloured and stable in air at room temperature. The complexes exhibit coordination number to be 4 and 6. The thermal behaviour of metal complexes shows that the hydrated complexes lose water molecules of hydration in the first and then is immediately followed by decomposition of ligand molecules in the subsequent steps.

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Abstract  

The paper aims to investigate cytogenetic and apoptotic responses of γ-irradiation in a radio-resistant cell strain designated as M5. Induced micronuclei, chromosomal aberrations, nuclear fragmentation and nucleosomal ladders by γ-irradiation were less at equal doses in M5 cells in comparison with that obtained in the parental Chinese hamster V79 cells. However, at equal survival, there were no differences in the end points studied. Results indicate that the residual damages that lead to reproductive cell death also resulted in the cytogenetic and apoptotic responses. We speculate that the repair efficiency in M5 cells was more efficient and increased DNA repair could be the cause of radiation resistance observed in M5 cells.

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Abstract  

Radish plant was collected along with root and soil from the nearby area of a Municipal Solid Waste dumping site of the metropolitan city of Kolkata, West Bengal, India and analyzed for a wide range of elements using the EDXRF technique with a 109Cd point source and a Si(Li) detector. The samples comprized of the root-soil, root and leaves. For quality control purposes, NIST standard reference material (SRM) 1648 Urban Particulate Matter had also been analyzed using the same procedure as for the samples. Concentrations of elements with X-ray energies in the range of 3–20 keV in the soil around the root and their uptake pattern by the root and the leaves have been estimated.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: D. Pant, G. Chaugule, K. Gupta, P. Kulkarni, P. Gurba, P. Janardan, R. Changrani, P. Dey, P. Pathak, D. Prabhu, A. Kanekar, and V. Manchanda

Abstract  

This paper deals with the optimization of experimental conditions for the estimation of Np in spent fuel dissolver solution using 2-thenoyltrifluoroacetone (HTTA) as extractant. The quantitative extraction of Np from the dissolver solution employing 0.5 M HTTA/xylene was followed by its estimation by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) after stripping it from the organic phase with 8 M HNO3. The reliability of the method was checked by standard addition technique. The method is precise and accurate yielding Np analytical recovery of 99 ± 1%.

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