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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. -
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. -
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. -
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. -
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. -
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. -
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. -
Bismuth (III) oxide decorated graphene oxide filled epoxy nanocomposites: thermo-mechanical and photon attenuation properties
In this study, bismuth (III) oxide (Bi2O3) decorated graphene oxide (GO) nanocomposites were employed as novel radioprotective fillers in the epoxy matrix. Decoration of GO with Bi2O3 would transform it as carrier for Bi2O3 particles, thereby enhancing the thermo-mechanical and radiation shielding properties of the epoxy composites through effective filler distribution. Structural and compositional studies confirmed the successful decoration of Bi2O3 on the surface of GO. Thereupon, epoxy composites containing decorated fillers at different loadings (5, 10 and 15 wt%) were synthesized using solution casting technique. The correlation between surface decoration and filler loading was systematically examined as function of thermo-mechanical, viscoelastic and radiation shielding properties of the composites. These nanocomposites displayed good thermal resistance (~ 450 C), high glass transition temperature (~ 136 C), elastic modulus (~ 4.36 GPa) and storage modulus, thereby confirming the improved dispersion and better interfacial adhesion in the composites. The formation of continuous filler network across epoxy matrix formed by decorated fillers significantly improved X-ray and ?-ray shielding properties of epoxy composites in the wide energy range of medical interest (301332 keV). Shielding efficiency of these lowly loaded BGO/epoxy composites were comparable with the composites containing Bi2O3 nanoparticles alone and highly loaded microcomposites. 2022 Japan Society for Composite Materials, Korean Society for Composite Materials and Informa UK Limited, trading as Taylor & Francis Group. -
Transparent and lead-free Dy3+ doped lithium borate glasses for photon and neutron shielding applications
The exploration of trivalent rare-earth ion-doped lithium calcium borate glasses has surged recently due to their potential applications in solid-state lasers, medical imaging, and radiation shielding. This study focuses on transparent and lead-free Dy3+ doped lithium borate glasses for their efficacy as versatile radiation shields. Glasses with the chemical composition 50(Li2O): 20(CaO): 30?x(B2O3): x(Dy2O3) (x = 0.0, 0.1, 0.3, 0.5 and 1.0 mol% Dy2O3) were investigated. The structural changes in the lithium calcium borate glasses with Dy2O3 were investigated using Fourier transform infrared spectra of the synthesized glass samples. Experimental mass attenuation coefficients (?/?) of the glasses have been determined using NaI(Tl) detector spectrometer in the energy range of 0.356-1.332 MeV. Photon interaction parameters were computed using PAGEX software in the energy range of 0.015-15 MeV. Relative dose distribution (RDD) and specific absorbed fraction of energy (SAFE) were also investigated. Additionally, macroscopic fast neutron removal cross-sections ( ? R ) were computed to estimate neutron shielding efficiencies. The sample with 1 mol% Dy2O3(LBD1), displayed superior photon and neutron attenuation properties. Glasses with lower Dy2O3 doping concentrations (?1 mol%) showed comparable half-value layer and effective atomic number to reference materials with higher doping concentrations. Increasing Dy2O3 doping concentration improved photon shielding parameters, with ? R values ranging from 0.1460 to 0.1475 cm?1, higher than those of ordinary concrete, RS-360, and other reference materials. The results highlight the potential of Dy3+ doped lithium borate glasses as effective radiation shields. Further investigations on chemical combinations and Dy2O3 doping concentrations are warranted to fabricate glasses with enhanced properties. 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
Natural polymer-based hydrogels as prospective tissue equivalent materials for radiation therapy and dosimetry
Natural polymer-based hydrogels have been extensively employed in tissue engineering and biomedical applications, owing to their biodegradability and biocompatibility. In the present work, we have investigated the efficacy of hydrogels such as agarose, hyaluronan, gelatin, carrageenan, chitosan, sodium alginate and collagen as tissue equivalent materials with respect to photon and charged particle (electron, proton and alpha particle) interactions, for use in radiation therapy and dosimetry. Tissue equivalence has been investigated by computing photon mass energy absorption coefficient (?en/?), kinetic energy released per unit mass (KERMA), equivalent atomic number (Zeq) and energy absorption build-up factors (EABF) relative to human tissues (soft tissue, cortical bone, skeletal muscle, breast tissue, lung tissue, adipose tissue, skin tissue, brain) in the energy range of 0.01515MeV. Ratio of effective atomic numbers (Zeff) have been examined for tissue-equivalence in the energy range of 10keV1GeV for charged particle interactions. Analysis using standard theoretical formulations revealed that all the selected natural polymers can serve as good tissue equivalent materials with respect to all human tissues except cortical bone. Notably, sodium alginate, collagen and hyaluronan are found to have radiation interaction characteristics close to that of human tissues. These results would be useful in deciding on the suitability of a natural polymer hydrogel as tissue substitute in the desired energy range. 2021, Australasian College of Physical Scientists and Engineers in Medicine. -
Lead-free inorganic metal perovskites beyond photovoltaics: Photon, charged particles and neutron shielding applications
Over the last few years, lead-free inorganic metal perovskites have gained impressive ground in empowering satellites in space exploration owing to their material stability and performance evolution under extreme space environments. The present work has examined the versatility of eight such perovskites as space radiation shielding materials by computing their photon, charged particles and neutron interaction parameters. Photon interaction parameters were calculated for a wide energy range using PAGEX software. The ranges of heavy charged particles (H, He, C, N, O, Ne, Mg, Si and Fe ions) in these perovskites were estimated using SRIM software in the energy range 1 keV10 GeV, and that of electrons was computed using ESTAR NIST software in the energy range 0.01 MeV1 GeV. Further, the macroscopic fast neutron removal cross-sections were also calculated to estimate the neutron shielding efficiencies. The examined shielding parameters of the perovskites varied depending on the radiation type and energy. Among the selected perovskites, Cs2TiI6 and Ba2AgIO6 displayed superior photon attenuation properties. A 3.5 cm thick Ba2AgIO6-based shield could reduce the incident radiation intensity to half its initial value, a thickness even lesser than that of Pb-glass. Besides, CsSnBr3 and La0.8Ca0.2Ni0.5Ti0.5O3 displayed the highest and lowest range values, respectively, for all heavy charged particles. Ba2AgIO6 showed electron stopping power (on par with Kovar) better than that of other examined materials. Interestingly, La0.8Ca0.2Ni0.5Ti0.5O3 demonstrated neutron removal cross-section values greater than that of standard neutron shielding materials - aluminium and polyethylene. On the whole, the present study not only demonstrates the employment prospects of eco-friendly perovskites for shielding space radiations but also suggests future prospects for research in this direction. 2022 Korean Nuclear Society -
Synthesis, in vitro and theoretical studies on newly synthesized deep blue emitting 4-(p-methylphenylsulfonyl-5-aryl/alkyl)oxazole analogues for biological and optoelectronic applications
In the present study, a series of 4,5-di-substituted oxazole derivatives (compounds 2a-p) were synthesized, using a novel methodology for the simultaneous determination of their biological and optoelectronic applications. Among the screened molecules, compounds 2j, 2 l and 2o showed very good antimicrobial potencies with MICs up to 1 g/mL. Furthermore, the photophysical parameters were estimated using theoretical and experimental techniques for optoelectronic applications. The excited-state dipole moment being higher than that of the ground state, investigated using solvato-chromatic method showed a redistribution of the electron densities in the excited state for the fluorophores. The HOMO-LUMO energies of the fluorophores estimated by using density functional theory (DFT) are found to be in good agreement with the experimental values. The electrophilic and nucleophilic sites were also recognized with the help of molecular electrostatic potential 3D plots using time-dependent-DFT computational analysis. The specific and non-specific interactions between the solutesolvent were analyzed by multiple linear regression analysis using Kamlet-Abound-Taft and Catalan parameters. Further, the global chemical reactivity descriptor parameter was also calculated. The photophysical properties of the fluorophores suggest that these may be considered as potential probes for OLED, solar cell, and chemosensor applications. 2022 Elsevier B.V. -
Perception vs. reality: Analysing the nexus between financial literacy and fintech adoption
Fintech has revolutionized the financial services sector, fundamentally transforming how individuals and businesses manage their finances. However, effective and responsible utilization of these innovative services may require a certain degree of financial competence. To explore this possibility, this study investigates the nexus between financial literacy and fintech usage in the Indian context, considering two distinct measures of financial literacy. Primary data were collected conveniently from 391 respondents through a cross-sectional survey. Probit regression was applied to analyze the relationship between the two dimensions of financial literacy and the adoption of fintech services across three segments: mobile banking, mobile payments, and digital lending. The findings reveal a positive relationship between individuals subjectively perceived financial literacy and their propensity to use all three fintech services. Conversely, objectively measured financial literacy demonstrates a positive association only with the likelihood of using mobile banking. The study also identifies demographic characteristics as contributing factors to variations in fintech adoption. The studys findings hold value for policymakers and fintech service providers, as they underscore the importance of enhancing individuals subjective perceptions of their financial abilities to promote wider adoption of fintech services. Shamli Prabhakaran, Mynavathi L., 2023. -
Exploring the far-reaching consequences of malnutrition during pregnancy and beyond: A comprehensive review
In India, maternal and infant malnutrition continues to be a significant contributor to health problems. Fetal malnutrition can result from an inadequate nutrient supply, necessary nutrition services, and ideal practices before, during, and following pregnancy. This comprehensive review delves into the complex relationships among hormone changes, microbial ecosystems, and nutrition, and how these relationships affect the health of mothers and their offspring. The review highlights how important it is to maintain good nutrition during pregnancy and to comprehend the dietary modifications that pregnant people make on their own to create interventions that work. Important minerals like calcium, iron, folic acid, iodine, and vitamin D are covered. Acknowledging the mutualistic association between the eating habits of mothers and the diverse microbiomes found in their gut, vagina, and oral channels, the review explores the influence on hormone levels and their consequences during gestation. Diverse fetal developmental needs are depicted by the table that outlines food requirements for each of the three trimesters. The detrimental effects of poor prenatal nutrition on a mothers health and its repercussions for neonates are examined. The effects of malnutrition after delivery, including difficulties throughout pregnancy, healing periods, and general effects on mental and physical health, are well studied. The study, which adopts a worldwide viewpoint, finds that societal norms, information gaps, and poverty are the main causes of malnutrition. Prevention techniques are discussed, emphasizing the significance of taking a comprehensive approach to addressing this vital issue in both the Indian and global contexts. 2024 Visagaa Publishing House. -
Value co-creation through search efforts and customer involvement impacting purchase intention of smart phones /
International Journal of Recent Technology And Engineering, Vol.8, Issue 3, pp.3894-3902, ISSN No: 2277-3878. -
The Optimization of Output of Wind Turbine with the Ongoing Grid System through BP Method Using ANN
Wind turbines are intricate devices that need careful planning, evaluation, and installation to guarantee peak performance under a range of environmental circumstances. Comprehensive load calculations, performance evaluations, and iterative optimisation processes are all part of the design process. However, complex simulation techniques are required to adequately depict the non-linear behaviour of wind turbine systems because of their complicated structure. Automation of optimisation processes and simulation executions is crucial to optimise the design process and manage the large number of simulations that are needed. This work provides a thorough framework using back propagation (BP) and artificial neural networks (ANN) for simulation and optimization that will make it easier to manage and automate the execution of iterative simulations during the design and development of wind turbines. The framework's main goals are to make design load case simulations easier and optimise activities more automatically. The framework makes it possible to optimise wind turbine systems and explore design options more effectively by automating these procedures. Three example optimisation jobs illustrate the framework's versatility and functionality. 2024 IEEE. -
Enhancing Disease Prediction in Healthcare: A Comparative Analysis of PSO and Extreme Learning Approach
The healthcare business generates a tremendous quantity of data, and the goal is to collect it and use it effectively for analysis, prediction, and treatment. The best approach to disease management is disease prevention through early intervention. There are a number of methods that can advise you on how to treat a specific sickness, but much fewer that can tell you with any degree of certainty if you will actually get sick in the first place. Preprocessing, feature selection, feature extraction, and model training are all parts of the proposed method. The suggested layout includes a preprocessing stage that takes care of things like moving average, missing values, and normalization. Feature selection describes the process of selecting the most relevant features from a dataset. After gathering features, the models are trained using PSO-ELM. The proposed strategy is superior to the widely used PSO and ELM. 2023 IEEE. -
Structured text programming to visualize the distribution of packages on a conveyor
Automation is a process of increasing production and reducing the downtime of any industry. With the integration of sensor data to the cloud using an OPC-VA communication protocol, the automation becomes more prominent and interesting. However, many existing industrial controllers do not support open platform communication unified architecture (OPC-VA) and it needs an IIoT device to connect the cloud. The existing programmable logic controller in any industry have to be connected to an IIoT device through Ethernet. Sensors connected to the controller will transmit the data to the IIoT device. The transmission can also be bidirectional. In this paper, a conveyor which distributes packages is simulated in Codesys and it is visualized in a human-machine interface (HMI) screen which is in-built in the software. The hardware set-up is made with the industrial controller to execute the same. A methodology to send the data from the controller to the cloud using open platform communication unified architecture (OPC-UA) is proposed 2023 IEEE. -
An Analytical Study on the influence of using Trimmed Gait Energy Images for Human Gait Biometrics using Deep Learning
Gait based human recognition is founded on the principle that every human being has a distinctive style of walking. With the rise in the use of video surveillance devices, gait is one of the most convenient biometrics to use, in forensics. This paper is an analytical study of the effect of using trimmed Gait Energy Images (GEI) for Human Recognition using different deep learning techniques. Gait energy images are a spatiotemporal, silhouette-based representation of the human gait. GEIs from the CASIA B Multiview dataset was used to build two other sets of data by subtracting the upper body Deep learning and transfer learning techniques including Convolution Neural Networks (CNN) and VGG16 algorithms had been implemented to carry out the recognition. Results showed that the performance of the model using upper body images gives a greater accuracy than the lower body images. It has also been observed that the accuracy of recognition provided by the upper part of the body is almost the same as that achieved by the whole body, which brings forth the idea that the upper part of the body is the most pertinent in Human Identification using Gait as a biometric. 2022 IEEE. -
Data-Driven Decision Making
This book delves into contemporary business analytics techniques across sectors for critical decision-making. It combines data, mathematical and statistical models, and information technology to present alternatives for decision evaluation. Offering systematic mechanisms, it explores business contexts, factors, and relationships to foster competitiveness. Beyond managerial perspectives, it includes contributions from professionals, academics, and scholars worldwide, delivering comprehensive knowledge and skills through diverse viewpoints, cases, and applications of analytical tools. As an international business science reference, it targets professionals, academics, researchers, doctoral scholars, postgraduate students, and research organizations seeking a nuanced understanding of modern business analytics. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.