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Jaiswal S.K.,Thapar University | Prakash R.,Thapar University | Acharya R.,Radiochemistry Division | Reddy A.V.R.,Bhabha Atomic Research Center | Tejo Prakash N.,Thapar University
Food Chemistry

Selenium (Se) hyperaccumulated Indian mustard (Brassica juncea) cultivated in a seleniferous region of India was collected and quantified for Se levels using instrumental neutron activation analysis (INAA). The seeds were subjected to oil extraction using a conventional screw extractor and Se content was estimated in seed, oil and oil cake. High uptake of selenium by the mustard seeds occurred, which was predominantly found to be retained and concentrated in the oil cake (143 ± 5.18 mg kg -1) when compared to seed before extraction (110 ± 3.04 mg kg -1) or oil (3.50 ± 0.66 mg L -1) after extraction. In conclusion, the study envisages application of Se-rich mustard oil or cake as sources of chemotherapeutic isoselenocyanates and exploitation of their bioactivity. © 2012 Elsevier Ltd. All rights reserved. Source

Shantibala Devi N.,Manipur University | Jaideva Singh L.,Manipur University | Pramodini Devi S.,Manipur University | Bhubon Singh R.K.,Manipur University | And 3 more authors.
Journal of Molecular Structure

Three new copper(II) complexes, bis(1-amidino-O-2-alkoxyethylurea)Cu(II)nitrate, where alkoxy = methoxy (1), ethoxy (2) or butoxy (3) have been synthesized and characterized. Electron paramagnetic resonance (EPR) spectra of complexes 2 and 3 gave half-field signal (ΔMs= ±2) ca. 1600 G, in addition to fine structure due to zero field splitting (ZFS) characteristics of the S = 1 system suggesting the formation of binuclear copper(II) complexes. Single crystal X-ray diffraction studies of complex 1 revealed that the copper atoms have tetra-coordinated square planar environments formed by two N atoms derived from two different ligands. The interaction of the copper(II) complexes with DNA were investigated by absorption spectroscopy, fluorescence spectroscopy, viscosity measurements and thermal denaturation studies. The values of binding constant (Kb) and the apparent binding constant (Kapp) calculated from the absorption and fluorescence spectral studies suggest that the binding strength of the three complexes are in the order 3 > 2 > 1. The three complexes interact with CT-DNA primarily by partial or non-intercalative modes. © 2014 Elsevier B.V. All rights reserved. Source

Manchanda V.K.,Radiochemistry Division | Manchanda V.K.,Sungkyunkwan University
Radiochimica Acta

Radiochemistry in India essentially blossomed under the auspices of the Department of Atomic Energy (DAE) for the last 55 years or so. Major activities in this area are centred at Bhabha Atomic Research Centre, Mumbai (BARC) and Indira Gandhi Centre for Atomic Research, Kalpakkam (IGCAR). Though there were several centers of excellence which were established by renowned radiochemists during the 1960s at the academic institutions in different parts of the country and nurtured by their close associates during the eighties and nineties, their glamour did not last long and only very few have sustained the challenges presented by social and technological upheaval of last five decades. Board of Research in Nuclear Sciences (BRNS), an organ of DAE has been in the forefront for promotion of education and research in nuclear sciences at academic institutions. It sponsors symposia in Nuclear and Radiochemistry (NUCAR), Nuclear Analytical Chemistry (NAC) and Applications of Radioisotopes in Chemistry, Environment and Biology (ARCEB) which are organized periodically to provide a platform for interaction of the radiochemists within and outside DAE. A professional body, viz. Indian Association of Nuclear Chemists and Allied Scientists (IANCAS), formed in early eighties at BARC, Mumbai has been spearheading the campaign to popularize the subject of radiochemistry in schools and colleges through workshops and publishing monographs and thematic bulletins regularly in the area of interest to the radiochemists. During the last five decades, radiochemistry programme at BARC has centered around attaining excellence in basic research utilizing radiations and radioisotopes to unravel various nuclear and chemical phenomena, related to actinides and fission products. This programme encompassed a number of research and development areas such as nuclear fission, nuclear reactions, nuclear probes for materials study, nuclear and chemical properties of actinides, actinide spectroscopy, separation science of actinides, thermodynamics and characterization of fuels, post irradiation examination, chemical and non destructive assay techniques for nuclear materials. Production and application of radioisotopes in societal benefit activities in agriculture, industry and health science was another facet of the radiochemistry programme at BARC. The radiochemistry programme at IGCAR has been focused on chemistry of fast reactor and fuel cycle related materials such as sodium and boron, in addition to the chemistry of actinides, fission products and pyrochemical studies related to processing of spent fuels. Publication of about 2000 peer reviewed papers in international journals of repute and award of Ph.D. degrees to more than 150 scientists is an evidence of the front line research activities pursued under this programme. All along the 55 years, sustained efforts were made to meet the growing challenges of closed nuclear fuel cycle (both thermal as well as fast). After five decades of continuous research and development perhaps one can feel satisfied that the programme could fulfil not only the dreams of its founders but is also ready to take on the future challenges related to the second and third stage of Indian nuclear power programme. © by Oldenbourg Wissenschaftsverlag, München. Source

Mulik V.K.,University of Pune | Naik H.,Radiochemistry Division | Suryanarayana S.V.,Nuclear Physics Division | Dhole S.D.,University of Pune | And 6 more authors.
Journal of Radioanalytical and Nuclear Chemistry

The 56Fe(n, p)56Mn reaction cross-section at neutron energies of 5.9 ± 0.6, 9.85 ± 0.38, 14.8 ± 0.1 and 15.5 ± 0.7 MeV from the 7Li(p, n) as well as 3H(d, n) reactions has been experimentally measured using activation and off-line γ-ray spectrometric technique. The experimentally determined 56Fe(n, p)56Mn reaction cross-sections from the present work were compared with the latest available evaluated nuclear data libraries of ENDF/B-VII.1, JENDL-4.0 and JEFF-3.1/A. The present data along with the literature data in a wide range of neutron energies were interpreted in terms of competition between different reaction channels. The measured cross-sections were also estimated theoretically using TALYS-1.4 and EMPIRE-2.19 computer codes over neutron energies from near threshold to 20 MeV to compare with the experimental data. © 2013 Akadémiai Kiadó, Budapest, Hungary. Source

Maheshwari P.,Radiochemistry Division | Mukherjee S.,Radiochemistry Division | Bhattacharya D.,Solid State Physics Division | Sen S.,Technical Physics Division | And 5 more authors.
ACS Applied Materials and Interfaces

Surface engineering of SiO2 dielectric using different self-assembled monolayer (SAM) has been carried out, and its effect on the molecular packing and growth behavior of copper phthalocyanine (CuPc) has been studied. A correlation between the growth behavior and performance of organic field effect transistors is examined. Depth profiling using positron annihilation and X-ray reflectivity techniques has been employed to characterize the interface between CuPc and the modified and/or unmodified dielectric. We observe the presence of structural defects or disorder due to disorientation of CuPc molecules on the unmodified dielectric and ordered arrangement on the modified dielectrics, consistent with the high charge carrier mobility in organic field effect transistors in the latter. The study also highlights the sensitivity of these techniques to the packing of CuPc molecules on SiO2 modified using different SAMs. Our study also signifies the sensitivity and utility of these two techniques in the characterization of buried interfaces in organic devices. © 2015 American Chemical Society. Source

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