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Prof. P. Venkataramaiah (P.V.), born on July 08, 1937, has been active in research for the past five decades in several areas of Nuclear Physics and Environmental Sciences. He has visited several Universities and research institutes in various countries such as Japan, Hong Kong, Singapore, France, the UK, Canada and the USA. Apart from research work he has also held many administrative positions and made revolutionary improvements in the education sector of India. Even after retirement, Prof. P.V. has actively involved himself inspiring and encouraging the younger generation at secondary level. As an honour for his untiring dedication even in his eighties, his colleagues and students have written articles about his contributions to research and education. This include contributions from Prof. P.V. himself along with Prof. K.S. Mallesh, Prof. N. Nagaiah, Prof. S.A. Bari, Prof. M. Venkateshwaralu, Shri. M. Vasudev, Dr K. Nagaraja, Mrs. Sreemathi Hariprasad and Dr N. Bhagyalakshmi. [ABSTRACT FROM AUTHOR]

Uranium occurs naturally in groundwater and surface water. Being a radioactive element, high uranium concentration can cause impact on human health. The health effects associated with consumption of uranium through water includes increased cancer risk and kidney toxicity. In view of this, an attempt was made in the present study to establish the level of radiological and chemical toxicity of uranium. Radiological toxicity was evaluated in terms of lifetime cancer risk and chemical toxicity through hazard quotient. For the said purpose, groundwater samples from the selected villages of the surrounding region of the Manchanabele reservoir, southwest of Bengaluru, were collected. The collected groundwater samples were analysed for Uranium mass concentration using Light emitting diode (LED) fluorimeter and is found to range from 0.88 to 581.47 ppb with a GM of 20.82 ppb. The result reveals that ~ 66% of the samples show concentration of uranium within the safe limit of 30 ppb as set by the World Health Organisation. The radiological risk estimated in terms of lifetime cancer risk is in the range of 0.0028 × 10−3 to 1.85 × 10−3 with a GM of 0.066 × 10−3. The chemical toxicity risk measured as lifetime annual daily dose is found to range from 0.03 to 21.65 μg per kg per d with a GM of 0.77 μg per kg per d. [ABSTRACT FROM AUTHOR]

Polydimethyl silicone rubber-based polymer composites filled with molybdenum and bismuth were fabricated using simple open mold cast technique. The physical and chemical structure and gamma shielding parameters like attenuation coefficient, half-value layer (HVL) thickness and relaxation length have been investigated for the said novel materials using X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and gamma ray spectrometer. XRD study reveals the crystalline nature of the composites. It is evident from FTIR studies that there is no chemical interaction between the polymer matrix and filler particles. The results of attenuation studies reveal that the linear attenuation coefficient increases with addition of Bi and Mo and is found to be 0.653, 1.341 and 1.017, 1.793 and 0.102, 0.152 cm−1 for 1MMB and 2MMB polymer composites at 80, 356 and 662 keV gamma rays, respectively. The HVL thickness of the materials is found to be 1.06, 0.51 and 0.68, 0.38 and 6.73, 4.532 cm for 1MMB (20Mo + 10Bi phr) and 2MMB (40Mo + 20Bi phr) at these energies, respectively. The mass attenuation coefficient of the novel composites 1MMB and 2MMB is found to be higher than the conventional materials like lead and barite for 356 keV gamma rays. In addition, the material is found to be light weight and flexible enabling to be molded in required forms, thus being a substitute for the material lead that is known to be heavy and toxic by nature. [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO2) nanoparticles (NPs) exhibit a variety of properties, which have prompted researchers to explore CeO2 NPs in various applications such as biomedical, electrochemical, gas sensing and display applications. CeO2 NPs capabilities were impacted by the type of synthesis mechanism. CeO2 NPs were synthesized by solution combustion method using neem leaves extract as a reducing agent. The synthesized sample is characterized with different techniques. The Bragg reflections confirm the formation of cubic spinel structure. The surface morphology consists of agglomerated NPs. The direct energy band gap was found to be 2.9 eV. X-ray radiation absorption properties were studied within 1 keV–100GeV range. The results indicate that CeO2 NPs found to be potential in radiation applications. [ABSTRACT FROM AUTHOR]

The measurement of 222Rn and 220Rn concentrations in air was carried out in 50 dwellings belonging to 20 locations in and around Mandya city, Karnataka. Annual mean values of 222Rn and 220Rn concentrations were found to be 22.4 ± 1.5 and 24.1 ± 1.8 Bq m−3, respectively. The total annual effective dose received by the general public due to radon and thoron was found to be 1.36 ± 0.08 mSv y−1. The doses to different organs and tissues were calculated using the International Commission on Radiological Protection (ICRP) model of the respiratory tract and inter-comparison was made. The flooring, roofing type and age of the buildings were noted and the radon levels with respect to these parameters were analysed and discussed. An attempt was made to predict the indoor radon levels in dwellings using the existing model which was based on the mass balance equation and the results were compared with measured values. [ABSTRACT FROM AUTHOR]

Polydimethyl silicone rubber-based polymer composites filled with molybdenum and bismuth were fabricated using simple open mold cast technique. The physical and chemical structure and gamma shielding parameters like attenuation coefficient, half-value layer (HVL) thickness and relaxation length have been investigated for the said novel materials using X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and gamma ray spectrometer. XRD study reveals the crystalline nature of the composites. It is evident from FTIR studies that there is no chemical interaction between the polymer matrix and filler particles. The results of attenuation studies reveal that the linear attenuation coefficient increases with addition of Bi and Mo and is found to be 0.653, 1.341 and 1.017, 1.793 and 0.102, 0.152 cm-1 for 1MMB and 2MMB polymer composites at 80, 356 and 662 keV gamma rays, respectively. The HVL thickness of the materials is found to be 1.06, 0.51 and 0.68, 0.38 and 6.73, 4.532 cm for 1MMB (20Mo + 10Bi phr) and 2MMB (40Mo + 20Bi phr) at these energies, respectively. The mass attenuation coefficient of the novel composites 1MMB and 2MMB is found to be higher than the conventional materials like lead and barite for 356 keV gamma rays. In addition, the material is found to be light weight and flexible enabling to be molded in required forms, thus being a substitute for the material lead that is known to be heavy and toxic by nature., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)