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Molecular detection of Cucumber mosaic virus in various chrysanthemum cultivars was attempted by RT-PCR and Southern hybridization tests using CMV specific primers and cloned probes, respectively. A pair of primers was designed from a conserved region of the Cucumber mosaic virus coat protein (CMV-CP) gene, capable of amplifying a product of ~650 bp from various CMV strains. RT-PCR using the total nucleic acid from infected leaf samples and the specific primers resulted in positive amplification of an expected size band of ~650 bp in most of the samples. The identity of the PCR amplicons was checked by Southern hybridization using the a32P-labelled DNA probes prepared from the cloned coat protein gene of a well-identified strain of CMV isolated from Amaranthus. Positive signal of hybridization of PCR products and CMV probes confirmed the identity of fected chrysanthemum samples.

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Abstract  

Gracilaria edulis, an edible red marine macro algae from three high background radiation areas (Arockiapuram, Kadiapattinam and Kurumpanai) on the southwest coast of Tamil Nadu, and one low background radiation area (Mandapam) on the southeast coast of Tamil Nadu, in India, were studied for variations in average gross alpha and beta radiation activities. Significant variations in average gross beta activities were observed while alpha activities showed only marginal variation. The average gross alpha activity was recorded high (61.51 Bq kg1) during the post southwest monsoon season, while it recorded lowest (25.48 Bq kg1) during the post northeast monsoon season. Average gross beta activity varied between seasons with the lowest level (211.55 Bq Kg−1) during post southwest monsoon season and the highest (413.33 Bq kg1) during post northeast monsoon season. Among the four locations, the gross alpha activity was high (70.95 ± 26.74 Bq Kg−1) in Arockiapuram and low (18.74 ± 6.32 Bq Kg−1) in Mandapam, while the gross beta activity was high (442.25 ± 168.53 Bq Kg−1) in Kurumpanai and low (158.63 ± 34.37 Bq Kg−1) in Mandapam. Average gross alpha activity in G. edulis was found significantly varying in terms of locations, while average gross beta activity for the same species recorded significant seasonal variation.

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Gerbera (Gerbera jamesonii) is a popular ornamental plant cultivated all over the world. It is grown in beds, pots and used as cut-flower in making bouquets and for decoration in ceremonial functions. Gerbera has been commercially cultivated by a large number of growers in India as a primary source of income, therefore, has high socioeconomic impact in floriculture industry. The gerbera cultivation areas in India are increasing day by day due to its uses and the market demands. Its cultivation has been hampered by a variety of diseases that affect its flower quality and quantity. Of them, the viral and phytoplasma diseases cause considerable losses in gerbera cultivation. In this review, we have described about the disease symptoms, detection methods and identification of causal virus and phytoplasma pathogens affecting gerbera production worldwide and their disease management strategies opted by the researchers for production of pathogen-free plants.

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Diffusion of sodium in Mn and Ti bearing sodium borosilicate glass used for the immobilization of the high level waste at the Waste Immobilization Plant, Tarapur has been studied by heterogeneous isotopic exchange using 24Na as the radiotracer for sodium. The temperature dependence of the self-diffusion coefficient of sodium in the glass was found to follow Arrhenius equation below the glass transition temperature.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Selvakumar, S. Aravindh, C. Kaushik, V. Katarani, Vidya Thorat, Prema Gireesan, V. Jayavignesh, K. Swaminathan, and Kanwar Raj

Abstract  

The present study involves the screening of silver nanoparticles containing carbonized yeast cells isolated from coconut cell sap for efficient adsorption of few long lived radionuclides like 137Cs55, 60Co27, 106Ru44, 239Pu94 and 241Am95. Yeast cells containing silver nanoparticles produced through biological reduction were subjected to carbonization (400 °C for 1 h) at atmospheric conditions and their properties were analyzed using fourier transform infra-red spectroscopy, X-ray diffraction, scanning electron microscope attached with energy dispersive spectroscopy and transmission electron microscope. The average size of the silver nanoparticles present on the surface of the carbonized silver containing yeast cells (CSY) was 19 ± 9 nm. The carbonized control yeast cells without silver exposure (CCY) did not contain any particles on its surface. The efficiency of CSY and CCY towards the radionuclide adsorption was studied in batch mode at fixed contact time, concentration, and at its native pH. CSY was efficient in removal of 239Pu94 (76.75%) and 106Ru44 (54.73%) whereas CCY showed efficient removal only for 241Am95 (62.89%). Both the adsorbents did not show any retention with respect to 60Co27 and 137Cs55. Based on the experimental data, decontamination factor and distribution coefficient (K d) were calculated and, from the values, it was observed that these adsorbents have greater potential to adsorb radionuclides.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: H. Naik, S. Surayanarayana, V. Mulik, P. Prajapati, B. Shivashankar, K. Jagadeesan, S. Thakare, D. Raj, S. Sharma, P. Bhagwat, S. Dhole, S. Ganesan, V. Bhoraskar, and A. Goswami

Abstract  

The 238U(n, γ)239U reaction cross-section at average neutron energy of 3.7 ± 0.3 MeV from the 7Li(p, n)7Be reaction has been determined using activation and off-line γ-ray spectrometric technique. The 238U(n, γ)239U and 238U(n, 2n)237U reaction cross-sections at average neutron energy of 9.85 ± 0.38 MeV from the same 7Li(p, n)7Be reaction have been also determined using the above technique. The experimentally determined 238U(n, γ)239U and 238U(n, 2n)237U reaction cross-sections were compared with the evaluated data of ENDF/B-VII, JENDL-4.0, JEFF-3.1 and CENDL-3.1. The experimental values were found to be in general agreement with the evaluated value based on ENDF/B-VII, and JENDL-4.0 but not with the JEFF-3.1 and CENDL-3.1. The present data along with literature data in a wide range of neutron energies were interpreted in terms of competition between different reaction channels including fission. The 238U(n, γ)239U and 238U(n, 2n)237U reaction cross-sections were also calculated theoretically using the TALYS 1.2 computer code and were also found to be in agreement experimental data.

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