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Thermal, mechanical and ?-ray shielding properties of micro- and nano-Ta2O5 loaded DGEBA epoxy resin composites
In this work, we have investigated the synergistic effect of micro- and nano-Ta2O5 fillers in the epoxy matrix on the thermal, mechanical, and radioprotective properties of the composites. Morphological analysis revealed uniform dispersion of fillers in the matrix. Both the thermal stability and tensile properties of matrices have enhanced in the presence of fillers. Although the nanocomposites showed significantly higher tensile strength and Youngs modulus compared to micro-composites, the enhancement in these properties was predominant at low loadings. Dynamic mechanical analysis indicated good interfacial adhesion and positive reinforcing effect on the matrix even at higher loading (30 wt%) of nano-Ta2O5. ?-Ray attenuation studies performed in the energy range of 0.3561.332 MeV revealed better ?-ray shielding ability of nanocomposites compared to microcomposites at same weight fraction of fillers. In particular, ?-ray attenuation at 0.356 MeV for 30 wt% nano-Ta2O5 loaded epoxy composite was enhanced by around 13% compared to the microcomposite at the same loading. Increased surface-to-volume ratio of nanofillers and consequent increase in matrix-filler adhesion and radiation-matter interaction have manifested in an overall enhancement in the thermal, mechanical, dynamic mechanical, and radiation shielding characteristics of nano-Ta2O5/epoxy composites, proving them as promising ?-ray shields. 2021 Wiley Periodicals LLC. -
Sodium alginate/bismuth (III) oxide composites for ?-ray shielding applications
In the present work, we have explored the efficacy of bismuth (III) oxide (Bi2O3) loaded, calcium ion cross-linked solution cast sodium alginate composite films for radioprotective applications. Calcium ion cross-linking increased the water and chemical resistance, which further improved on introduction of Bi2O3 into the composites. The 40 wt% Bi2O3 loaded films showed good heat resistance with the peak degradation temperature reaching as high as 251C. The Bi2O3 loaded composites showed enhanced tensile strength (TS) and Youngs modulus (YM). Compared to high-modulus polymers like epoxy, high-density polyethylene (HDPE) and poly (vinyl chloride) (PVC), these exhibit relatively greater extent of stretching before breaking. The ?-ray attenuation experiments showed that mass attenuation coefficients of the composites at various ?-ray energies increased with filler loading. These composites are effective in shielding ?-rays from radioactive sources like 137Cs, 22Na, 133Ba, and 60Co that are widely employed in several medical and industrial applications. The overall enhancement in thermal, mechanical, and radiation shielding characteristics of the composites may be attributed to the uniform distribution of the fillers in alginate matrix. These nontoxic sodium alginate/Bi2O3 composites can be used as soft and biodegradable radiation shields, which may be processed to wearable forms. 2020 Wiley Periodicals LLC. -
Synthetic polymer hydrogels as potential tissue phantoms in radiation therapy and dosimetry
The efficacy of synthetic polymers as hydrogel phantoms for radiation therapy and dosimetry has been investigated for photon and charged particle (electron, proton and alpha particle) interactions. Tissue equivalence has been studied in terms of photon mass energy-absorption coefficients, KERMA (kinetic energy released per unit mass), equivalent atomic number and energy absorption build-up factors, relative to human tissues (skin, soft tissue, cortical bone and skeletal muscle), in the energy range 0.015-15 MeV. For charged particle interactions, ratio of effective atomic number is examined for tissue-equivalence in the energy region of 10 keV-1 GeV. Well established theoretical formulations are used for computation of photon mass-energy absorption effective atomic number, electron density and KERMA. Five-parameter geometric progression (G-P) fitting approximation is used to compute the values of energy absorption build-up factors. Effective atomic number for charged particle interaction is determined using logarithmic interpolation method. Using the analytical methodology, it has been revealed that all the selected synthetic polymers have good tissue-equivalence relative to all tissue except cortical bone. In particular, polyglycolic acid (PGA) and poly-lactic-co-glycolic acid (PLGA) prove to be best substitute material for photon interactions. On the other hand, % difference between effective atomic number for charged particle relative to human tissues is found least for polyethylene glycol (PEG) demonstrating adequate tissue-equivalence. Therefore, the present study is expected to be useful to choose most appropriate phantom material for radiation therapy. 2020 IOP Publishing Ltd. -
Nanoparticles as fillers in composites for x-ray and gamma-ray shielding: A review
In last few decades, nanomaterials have gained enormous attention in the scientific industry due to their tunable physico-chemical and biological properties with enhanced performance over their bulk counterparts. In particular, nanoparticles have been extensively investigated for their usefulness in X-ray and gamma-ray shielding applications. Various elements and compounds, with high atomic numbers and effective atomic numbers respectively, have the potential to form nanoparticles that offer remarkable enhancement in the shielding performance. Composites, obtained by doping different nanoparticles into structural matrices (concrete, glass, or polymers), not only possess striking thermo-mechanical properties but also are effective shielding materials to replace conventional lead shields. This review is an attempt to throw light on various aspects of nanoparticles and their influence on shielding effectiveness. The authors also summarize the experimental findings so as to highlight the potential underlying the radiation-matter interaction mechanism in nanostructured systems. Copyright 2023, IGI Global. -
Recent advances in lightweight epoxy-based composites for X-Ray and y-Ray shielding applications
Rapidly advancing technologies in the nuclear industry have led to the increased use of X-rays and ?-rays in our day-to-day life. They have emerged to be an integral part of several industries including medical diagnostics and imaging, nuclear medicine, reactor research facilities, industrial gauging, agricultural irradiation, geological exploration and security purposes. However, considering the adverse effects of prolonged exposure to these radiations on human health, this is also a cause of concern for mankind and radiation shielding and protection have become issues of paramount importance. In the search for alternatives to conventional shielding materials such as lead, metals, glass composites, ceramics and concretes, epoxy-based composites have emerged as promising X-ray and ?-ray shields. Material properties like high mechanical and bonding strength, high temperature resistance, low electrical conductivity and thermal expansion coefficients, dielectric constant with minimal shrinking stress and lightweight structure render epoxy composites to be particularly suitable for structural applications. Epoxy composites incorporated with fillers/additives such as inorganic metal oxides, carbon fibers, clay and carbon nanotubes are an emerging class of high-performance materials. The primary focus of this article is to present a detailed review on the recent research directed towards developing epoxy-based materials for radiation shielding applications. Influence of filler loading, filler size and interfacial adhesion on microstructural, thermo-mechanical and radioprotective efficacy of epoxy composites are discussed. We present a general overview and propose new possibilities for further research in this direction. 2022 Nova Science Publishers, Inc. -
Preparation and Characterization of Tungsten Carbide/Epoxy Composites for J-Ray Shielding
Polymer composites have attracted considerable attention as potential light weight and cost-effective shielding materials which could be used for applications in nuclear reactors, nuclear waste transportation, as protective cloth/apron for personnel in hospitals, and shielding instruments on-board satellites from space radiations. In this context, we have developed diglycidyl ether of bisphenol A (DGEBA)-based epoxy resin composites loaded with tungsten carbide (WC) for J-ray shielding. Epoxy composites containing different loadings (0, 10, 30 and 50 wt%) of WC were synthesized by room temperature solution casting technique. Structural and morphological studies of the composites were performed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Thermal and tensile properties of epoxy were enhanced in the presence of WC fillers. Thermogravimetric analysis revealed the major degradation temperature occurring between 430C and 580C for all epoxy/WC composites. The tensile strength and Youngs modulus of the composites enhanced with loading, owing to greater intermolecular reinforcing effect, uniform stress distribution and enhanced energy-absorbing capacity. J-Ray attenuation studies performed in the energy region of 0.356 1.332 MeV using NaI(Tl) detector spectrometer showed the 50 wt% tungsten carbide/epoxy composites to have highest radiation attenuation at all the energies. The overall enhancement in thermal, mechanical, and radiation shielding characteristics of the composites may be attributed to the uniformity in distribution of the fillers in epoxy matrix. These nontoxic tungsten carbide/epoxy composites may be suitable as materials for shielding in radiation environments. 2022 American Institute of Physics Inc.. All rights reserved. -
X-Ray and ?-Ray Shielding Efficiency of Polymer Composites: Choice of Fillers, Effect of Loading and Filler Size, Photon Energy and Multifunctionality
Use of X-rays and ?-rays have become inevitable in medical sectors like radiology, interventional cardiology and diagnostic imaging, radiation physics laboratories, nuclear reactors and accelerator facilities. As radiation exposures above permitted levels pose potential risk to personnel working in close proximity to these facilities, protective measures aimed at reducing the exposure for safeguarding against harmful effects of ionizing radiations are essential. Traditionally, lead and lead based materials have been used as efficient radiation shielding materials owing to the high atomic number and high density of lead. Presently, use of lead is discouraged due to its heavy weight, toxicity and long-term effects on the environment. Consequently, the last two decades have seen research on light weight and cost-effective polymer composites with appropriate additives, having good workability, high specific strength, thermo-chemical stability and radiation shielding efficacy, gaining momentum. This article gives an overview of the state-of-the-art polymer composites reinforced with different fillers studied for their use as effective radiation shields. Here, we summarize the recent advancement and current trends in polymer composites-based radiation shields highlighting the different approaches adopted, choice of polymer/fillers, shielding effectiveness in terms of either linear and/or mass attenuation coefficients, for those who venture into radiation research and development. 2022 Taylor & Francis Group, LLC. -
Enhanced visible light induced dye degradation and antibacterial activities of ZnO/NiO nanocomposite synthesized using Clitoria ternatea flower extract
In this study, ZnO/NiO Nanocomposites (NCs) were prepared using a rapid, simple and eco-friendly green synthesis method using medicinal flower extract of Clitoria ternatea and their visible light assisted dye degradation and antibacterial properties were investigated. The synthesised ZnO/NiO NCs were characterised by ultravioletvisible (UVVis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), High resolution transmission electron microscopy (TEM) and Selected area electron diffraction (SAED) studies. XRD results revealed that ZnO/NiO NCs exhibit hexagonal wurtzite and cubic crystal structure with an average crystallite size of 18 nm. HRTEM images revealed roughly spherical and hexagonal morphology with an average particle size of 23 nm. The antibacterial activity of ZnO/NiO NCs examined against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria using well diffusion method indicated significant antibacterial activity. The photocatalytic activity of the ZnO/NiO NCs showed 83.4 % and 84.4 % of dye degradation efficiency, respectively against Bromophenol Blue (BPB) and Crystal Violet (CV) dye for 150 min under sun light irradiation. The result shows that the ZnO/NiO NCs investigated in this study exhibited a strong potential agent and was successful in the removal of dye from wastewater. 2022 Elsevier B.V. -
A simple software for swift computation of photon and charged particle interaction parameters: PAGEX
PAGEX is a compact and user-friendly cross-platform software developed for swift computation of photon (X-ray and ?-ray) and charged particle interaction parameters for various applications. It is designed based on well-established theoretical formulations and computational techniques integrating various Python packages to effectively calculate parameters such as partial/total photon interaction cross-sections and mass attenuation coefficients, charged particle mass stopping powers and cross-sections, effective atomic number and electron density, mass-energy absorption coefficient, KERMA and build-up factors over a wide energy range. This tool is capable of generating both tabular and graphical outputs which can be saved in any user desired format. PAGEX has been verified against other widely employed software and databases, demonstrating good agreement. This software which facilitates robust computation is freely available from the authors. 2021 Elsevier Ltd -
Blocking intrusion logic using optimized multi-head convolution in wireless sensor network
Wireless sensor nodes (WSN) combine sensing and communication capabilities in the smallest sensor network component. Sensor nodes have basic networking capabilities, such as wireless connection with other nodes, data storage, and a microcontroller to do basic processing. The intrusion detection problem is well analyzed and there exist numerous techniques to solve this issue but suffer will poor intrusion detection accuracy and a higher false alarm ratio. To overcome this challenge, a novel Intrusion Detection via Salp Swarm Optimization based Deep Learning Algorithm (ID-SODA) has been proposed which classifies intrusion node and non-intrusion node. The proposed ID-SODA technique uses the k-means clustering algorithm to perform clustering. The Salp Swarm Optimization (SSO) technique takes into residual energy, distance, and cost while choosing the cluster head selection (CHS). The CHS is given the input to a multi-head convolutional neural network (MHCNN), which will classify into intrusion node and non-intrusion node. The performance analysis of the suggested ID-SODA is evaluated based on the parameters like accuracy, precision, F1 score, detection rate, recall, false alarm rate, and false negative rate. The suggested ID-SODA achieves an accuracy range of 98.95%. The result shows that the suggested ID-SODA improves the overall accuracy better than 6.56%, 2.94%, and 2.95% in SMOTE, SLGBM, and GWOSVM-IDS respectively. 2023 - IOS Press. All rights reserved. -
Effective atomic number and electron density of some biologically important lipids for electron, proton, alpha particle and photon interactions
X-ray, ?-ray and charged particle interaction parameters of biomolecules are useful in medical diagnosis and radiation therapy as exposure to radiations can cause energy of photons and charged particles to be deposited in body through various interaction processes. With this in view, the effective atomic number (Zeff) and electron density (Neff) of some biologically important lipids for X-ray, ?-ray and charged particle interactions were studied in the energy range 10 keV500 MeV using logarithmic interpolation method. A non-monotonic variation in Zeff values was observed for protons and alpha particles in low and intermediate energy regions respectively whereas a sudden increase in Zeff was observed for electron interaction in higher energy region. Zeff values were maximum in higher energy region for total electron interactions whereas maximum values of Zeff for total alpha particle interactions were at relatively lower energies. Highest Zeff values were found at lower energy region of photoelectric absorption dominance for photon interactions. Variation in Neff seems to be similar to variation in Zeff as they are inter-related. 2020 Elsevier Ltd -
The dharma of Kama: Kamasra's morality of integrated Purusartha
[No abstract available] -
Impact of job stress and work-life balance on turnover intention among Indian healthcare workers
The Healthcare sector is widely regarded as a high-stress-inducing environment, with considerable studies examining job stress and work-life balance in the healthcare sector since the COVID-19 pandemic. While these factors are well-documented, there is a growing need to shift the focus towards rising turnover rates within the industry post-pandemic. With this background, the study aims to examine the impact of job stress and work-life balance on turnover intentions among doctors by delving deeper into the dimensions of these variables and probing the effect of demographics on these variables. The proposed research employed a quantitative design to gather data from 127 healthcare doctors using purposive sampling. The data for this study were collected through an online Google form designed with three validated scales, which comprised doctors from diverse specializations and years of experience. The findings revealed that time stress significantly impacts work interference with personal life (WIPL) and personal life interference with work (PLIW). Personal life interference with work (PLIW) emerged as the strongest determinant of turnover intentions. Further, a greater psychological strain was encountered among female doctors than their male counterparts, implying that gender also had a potential influence on the outcome of the study. As a result, the study offers recommendations that can guide the retention strategies in healthcare organizations and promote a healthier and sustainable workforce. The Author(s) 2026. -
The family strengths of the Lambhanis of Bellary district /
The study titled The Family Strengths of the Lambhanis of Bellary District aimed at identifying and exploring Family Strengths of the Lambhanis their perpetuation. The study was based on the Family Strengths Model using an Interpretivistic Research Philosophy and a Grounded Theory Research Paradigm within a Qualitative Framework. The sample of the study was taken through a key informant. The participants were from Dasarhalli Thanda, Bellary District, Karnataka. They were all adults both men and women. Three Focus Groups were conducted and the interviews were unstructured, data was collected until Data Saturation was reached. The data was recorded/taped, translated and transcripts written. The data gathered was then coded based on the Grounded Theory Method proposed by Strauss and Corbin (1998). -
Tuning WO3 film properties for electrochromic applications via annealing and oxygen pressure
The objective of this investigation was to examine the intricate relationship between annealing temperature and oxygen partial pressure (PaO2) in regard to morphological, structural, and electrochemical properties of tungsten trioxide (WO3) films that were produced through sputtering. The films were deposited under two different PaO2 values, specifically 0.3 mTorr and 0.5 mTorr, and then underwent annealing at various temperatures: room temperature, 100, 200, 300, and 400 degrees Celsius. X-ray diffraction (XRD) analysis revealed a temperature-dependent transition from an amorphous to a crystalline phase. Morphological analyses conducted with scanning electron microscopy (SEM) indicated a trend towards a smoother surface as both the annealing temperature and PaO2 rose. At 400 C, the films exhibited a granular surface finish. Significantly, the film fabricated at 0.3 mTorr and subjected to room temperature (RT) annealing showed cracks, indicating inherent stress in the film. Electrochemical evaluations revealed that the WO3 film deposited at 0.5 mTorr and annealed later at 200 C demonstrated enhanced redox performance, better diffusion of ions, and remarkable reversibility. Impressive results were demonstrated in optical studies, attaining 83 % optical modulation, colouration efficiency (CE) up to 30.54 cm/C, and swift switching durations of 1.17 s for colouration and 0.82 s for decolouration. Moreover, cycling tests showed negligible degradation after 100 cycles for the films deposited at 0.5 mTorr PaO2 and treated at 200 C, emphasizing their resilience. This study furnishes a comprehensive knowledge of the consequences of annealing temperature and PaO2 collectively on WO3 films, highlighting the novel strategy of enhancing electrochromic efficacy by modifying temperature and meticulously balancing the PaO2, thus contributing to the progress of energy-efficient smart materials. 2025 -
Precision agriculture takes flight: Drone technology in crop management
[No abstract available] -
Streamlined electrochemical harvesting of cobalt and nickel from soft cemented carbide scrap for superior supercapacitors
We propose a complete circular economy and sustainability model from soft cemented carbide scrap to supercapacitor application. An enhanced recovery of cobalt and nickel was observed when deep eutectic solvent was used. A comparative in-situ electrochemical deposition of the recovered metals was done on stainless steel (SS), SS/activated carbon (AC), and SS/AC/polyaniline (PANI). The optimization of electrochemical extraction was carried out by varying voltage, time, and temperature. The surface area and conductive polymer's electronic distribution contributed to different surface morphological deposition of specific metals on them. Unique fluffy particle deposition was observed on the surface as fine grain particles with uniform particle size within 1 m. The fabricated supercapacitors showed the pseudocapacitance behaviour. The presence of metal oxide nanocomposite deposition as the active material is particularly pronounced in the SS/AC/PANI device due to the inclusion of PANI as an active material and its substantial contribution to pseudocapacitance. The higher charge-discharge time of SS/AC/PANI at the same current densities compared to SS/AC may be due to the above-mentioned additional contribution of PANI's quickly reversible redox behavior. Hence, the overall electrochemical extraction from scrap to supercapacitor will undoubtedly lead to achieving the sustainable development goals (SDGs) 2024 -
Electrochemical cobalt extraction from grinding sludge for supercapacitor applications via hydro- and solvometallurgical processes
Cobalt is a critical material for energy storage applications, including supercapacitors, but its supply is constrained by geopolitical and environmental challenges. This study presents a sustainable approach for cobalt recovery from cemented tungsten carbide grinding sludge via deep eutectic solvents (DESs) and evaluates the electrochemical performance of the recovered materials in supercapacitors. Electrochemical extraction was optimized at 4 V and 10 mA/cm2, achieving a cobalt concentration of 2900 mg/L in the DES. The cobalt was then recovered as cobalt oxalate via solvometallurgical (Route 1) and hydrometallurgical (Route 2) processes and subsequently calcined into cobalt oxide. Characterization revealed that the solvometallurgical route yielded finer, porous particles with enhanced electrochemical properties. The recovered cobalt oxalate and cobalt oxide were utilized in supercapacitor electrodes, demonstrating superior electrochemical performance when combined with activated carbon (AC). Supercapacitors incorporating cobalt oxide from route 1 with AC achieved a specific capacitance of 95 F/g, outperforming cobalt oxalate-based electrodes (89 F/g) at 1 mA/g. The AC-modified electrodes exhibited improved energy and power densities, with stable capacitance retention over 1000 cycles. Comparative analysis with direct deposition methods highlighted the multistep recovery process as a promising route for scalable cobalt recycling. This study underscores the potential of DES-based electrochemical extraction as an environmentally friendly alternative for critical metal recovery, aligning with circular economy principles and sustainable energy storage solutions. 2025 The Authors -
READING AND ENGAGING WITH KACEN CALLENDERS MOONFLOWER THROUGH INTERSECTIONAL PEDAGOGIES
This chapter argues that privileged perspectives can be decentered using intersectional pedagogies when engaging with literary texts such as Moonflower, a novel that engages children with vital topics relating to race, gender, and mental health. 2024 selection and editorial matter, KaaVonia Hinton and Karen Michele Chandler; individual chapters, the contributors. All rights reserved. -
The Horror, the Horror! Mediatised Narrativisation of Gendered Violence
[No abstract available]