Faculty Publications
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Item Effect of mix parameters and hydrogen loading on neutron radiation shielding characteristics of latex modified concrete mixes(Elsevier Ltd, 2015) Malkapur, S.M.; Satdive, H.; Narasimhan, M.C.; Karkera, N.B.; Goverdhan, P.; Sathian, V.With the tremendous surge in the usage of radioactive materials in industry, education and research, medicine and other fields, it becomes a concern to protect the working personnel and common people around, from hazardous radiation leakages that may seriously affect their health. Among the different types of radiation, gamma and neutron radiations require adequate shielding. There have been several attempts to develop newer concretes and evaluate their neutron radiation shielding characteristics. In the present study, an attempt has been made to study the effect of varying the mix parameters and hence the resulting total hydrogen content on the neutron radiation shielding characteristics of Latex Modified Concrete (LMC) mixes. The experiments are planned in such a way that the hydrogen content of the mixes is varied by controlling the mix parameters i.e., cement content, water/cement ratio and polymer/cement ratio of LMC mixes. The results are statistically analyzed. It is found that definite improvements could be achieved in neutron radiation shielding characteristics of LMC mixes as compared to ordinary concrete, with the increase in hydrogen concentration effected by changes in mix parameters. © 2015 Elsevier Ltd All rights reserved.Item Neutron radiation shielding properties of polymer incorporated self compacting concrete mixes(Elsevier Ltd, 2017) Malkapur, S.M.; Divakar, L.; Narasimhan, M.C.; Karkera, N.B.; Goverdhan, P.; Sathian, V.; Prasad, N.K.In this work, the neutron radiation shielding characteristics of a class of novel polymer-incorporated self-compacting concrete (PISCC) mixes are evaluated. Pulverized high density polyethylene (HDPE) material was used, at three different reference volumes, as a partial replacement to river sand in conventional concrete mixes. By such partial replacement of sand with polymer, additional hydrogen contents are incorporated in these concrete mixes and their effect on the neutron radiation shielding properties are studied. It has been observed from the initial set of experiments that there is a definite trend of reductions in the neutron flux and dose transmission factor values in these PISCC mixes vis-à-vis ordinary concrete mix. Also, the fact that quite similar enhanced shielding results are recorded even when reprocessed HDPE material is used in lieu of the virgin HDPE attracts further attention. © 2017 Elsevier LtdItem Fresh and hardened properties of polymer incorporated self compacting concrete mixes for neutron radiation shielding(Elsevier Ltd, 2017) Malkapur, S.M.; Divakar, L.; Narasimhan, M.C.; Karkera, N.B.; Goverdhan, P.; Sathian, V.; Prasad, N.K.Several works in the past have reported that the hydrogen content in the hydrated concrete plays an important role in shielding the neutron radiation; higher the hydrogen content, better is the neutron radiation shielding. In this study, pulverised high density polyethylene (HDPE) material is used as an additional source of hydrogen within concrete to develop a novel class of Polymer-Incorporated Self-Compacting Concrete (PISCC) mixes for enhanced neutron radiation shielding. The HDPE material was incorporated as a partial replacement to river sand. It is found that the PISCC mixes have satisfactory fresh and hardened properties and enhanced neutron radiation shielding properties. © 2017 Elsevier LtdItem Waste-polymer incorporated concrete mixes for neutron and gamma radiation shielding(Elsevier Ltd, 2021) Malkapur, S.M.; Ghodke, S.S.; Sujatha, P.N.; Singh, Y.; Shivakumar, K.S.; Sen, M.; Narasimhan, M.C.; Pulgur, A.V.In this paper, attempts are made to use waste plastics to make a novel Waste Polymer Incorporated Concrete (WPIC) mixes for gamma and neutron radiation shielding purposes. These mixes are achieved by simultaneous incorporation of waste polymeric material and high density fine and coarse aggregate components from iron industry in place of conventional ingredients. The results have indicated that the waste plastics along with by-products of iron industry can be conveniently used to make concrete mixes which have acceptable compressive strength characteristics and significantly enhanced shielding capabilities with respect to both gamma and neutron radiations. © 2021 Elsevier LtdItem TeO2 for enhancing structural, mechanical, optical, gamma and neutron radiation shielding performance of bismuth borosilicate glasses(Elsevier Ltd, 2023) D'Souza, A.N.; Padasale, B.; Murari, M.S.; Karunakara, N.; Sayyed, M.I.; Elsafi, M.; Al-Ghamdi, H.; Almuqrin, A.H.; Kamath, S.D.The synthesized 12Bi2O3– 8BaO–12ZnO-0.5CeO2-17.5SiO2- (50-x) B2O3- xTeO2 glasses with x = 0, 10, 20, 30 and 40 mol% (coded BiTe-0 to BiTe-40) were investigated in terms of physical, structural, optical and mechanical properties to examine the influence of CeO2 and TeO2 on the heavy metal oxide (HMO) borosilicate network. Density values increased continuously with increasing TeO2 concentration with BiTe-40 glass exhibiting maximum value of 5.0875 gcm−3. This property helped in enhancement of refractive index values from 1.769 for BiTe-0 to 1.942 for BiTe-40. Fourier transform infrared (FTIR) analysis of studied glasses revealed the presence of additional small peak at 683 cm−1 in BiTe-30 and BiTe-40 which confirmed the formation of stable TeO4 units in the glass network. The deep brown colour of the glass existing due to bismuth's presence was nullified by CeO2 and TeO2 additives which improved transparency of the glass. Urbach analysis of these glasses led to optical bandgap variation between 3.27 eV and 2.73 eV for 0–40 mol% TeO2 concentration. Makishima and Mackenzie model was utilized for evaluation of elastic property of the glasses, and Poisson's ratio ranging between 1.935 and 1.953 was obtained. Vickers micro-indentation test on the current glasses revealed decreasing microhardness from 4.116 to 4.076 GPa with TeO2 variation from 0 to 40 mol% at 9.8 N load. Gamma radiation shielding parameters were determined using Phy-X/PSD software and it was found that BiTe-40 glass produce maximum MAC (mass attenuation co-efficient) values in high photon energy region 3.5–15 MeV. The present article also contains a detailed emphasis on behaviour of gamma radiation build-up factors at different incident photon energy and TeO2 concentration. The increasing trend of exposure build up factor (EBF) was seen with increasing penetration depth inside the samples at all energies, indicating that glasses of larger thickness improve the escape probability of photons. Meanwhile, fast neutron removal cross-section (FNRCS) was highest for BiTe-10 sample (0.10118 cm−1) which also surpassed the value of ordinary concrete (0.093 cm−1). Overall, the present glass system bested other conventional shields available commercially in terms of gamma and neutron radiation shielding effectiveness. © 2022 Elsevier B.V.