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BoxBehnken design and experimental study of ciprofloxacin degradation over Ag2O/CeO2/g-C3N4 nanocomposites
Abstract: The presence of pharmaceutical residues notably antibiotics in the environment is an increasing concern due to their persistence and toxicity. Developing efficient and eco-friendly methods to eliminate antibiotic residues from water bodies has become a major environmental challenge. CeO2 doped with a heteroatom forms a hybrid structure with g-C3N4 and could serve as an efficient photocatalytic agent. In this study, CeO2/g-C3N4 and Ag2O/CeO2/g-C3N4 hybrid catalysts were prepared for UV light degradation of ciprofloxacin (CIP) antibiotic. The various factors that influence the degradation were experimentally optimized. The kinetics of the degradation was investigated using the LangmuirHinshelwood kinetic model. The effect of three operational parameters influencing the photocatalytic degradation has been evaluated using BoxBehnken design of response surface methodology. The highest degradation of CIP was observed at CIP concentration of 10?g/L with a catalyst amount of 30mg after 2.5h. Efficient charge separation was achieved from the dopant and the existing integrated electric field of the heterojunction showed impressive higher activity. Graphic abstract: [Figure not available: see fulltext.]. 2020, Islamic Azad University (IAU). -
Response surface optimization of heat transfer rate in Falkner-Skan flow of ZnO ? EG nanoliquid over a moving wedge: Sensitivity analysis
In this work, the optimization of the heat transfer rate in the Falkner-Skan flow of ethylene glycol-based ZnO nanoliquid passing through a moving wedge is performed using the Response Surface Methodology (RSM). The experimentally estimated nanoliquid properties are included in the calculations for realistic modeling. The heat transfer rate is optimized through the use of the numerical experiment based on the face-centered central composite design (CCF). The sensitivity of the heat transfer rate is evaluated using the obtained quadratic model. The impact of the relevant parameters is displayed graphically using the finite difference method-based solution procedure and analyzed in detail. The interactive impacts of the key parameters are also evaluated using three-dimensional surface plots. The maximum sensitivity of the heat transfer rate is towards the moving wedge parameter. The optimized rate of heat transfer occurs at the high levels of the radiation aspect, moving wedge parameter, and nanoparticle volume fraction. The interactive impacts of the nanoparticles volume fraction and the Falkner-Skan index were found to be non-linear. The movement of the wedge was found to have a significant impact on both the flow field and the rate of heat transfer. 2021 Elsevier Ltd -
Valorization of agro-industrial fruit peel waste to fluorescent nanocarbon sensor: Ultrasensitive detection of potentially hazardous tropane alkaloid
Millions of tonnes of agro-industrial waste are generated each year globally, with the vast majority of it going untreated, underutilized, and disposed of by burning or landfilling, causing severe environmental distress and economic downturn. A practical solution to this global issue is to use green chemistry to convert this waste into value-added products. Accordingly, in the present study, agro-industrial orange peel waste was valorized into fluorescent nanodiamond-like carbon sensor via a green route involving hydrothermal treatment of microwave carbonized orange peel waste. The developed sensor, used for the fluorescence detection of potentially hazardous drug atropine sulfate, exhibits unique dual linearity over concentration ranges of 300 nM to 1 M and from 1 M to 10 M, as well as ultra-low sensitivity of 34.42 nM and 356.46 nM, respectively. Additionally, the sensor demonstrates excellent reproducibility, high stability, and satisfactory recovery when used to identify and quantify atropine sulfate in biological samples and commercially available pharmaceuticals, indicating promising multidisciplinary applications. [Figure not available: see fulltext.] 2021, Higher Education Press. -
Magnetic coupling across the antiferromagnetic-antiferromagnetic interface
We investigate the magnetic coupling across the antiferromagnetic-antiferromagnetic (AFM-AFM) interface for the prototypical CoO-NiO bilayer system where the bulk Nl temperature (T N ) of NiO is higher than that of CoO. Using the temperature-dependent exchange-scattered electron intensities from the surface AFM lattice, the surface T N of CoO was estimated as a function of the CoO/NiO film thicknesses. Our results show that the surface T N of CoO layers is enhanced significantly from its bulk T N value and approaching the T N of the NiO layers, as the thickness of the CoO layers is reduced to the monolayer limit. Thus, thinner CoO layers are found to have higher T N than thicker layers on NiO, contrasting with the expected finite-size behavior. In addition to the short-range magnetic exchange coupling at the CoO-NiO interface, we observe the existence of a longer-range magnetic coupling across the interface, mediated by the magnetic correlations. Thus, the magnetic proximity effect is attributed to a combination of a short-range and a weaker long-range magnetic coupling, explaining the long AFM order propagation length in AFM-AFM superlattices and bilayers. Further, our results indicate a new approach to tune the AFM Nl temperature by varying the individual layer thickness of the bilayer system through the magnetic proximity effect. 2021 IOP Publishing Ltd. -
Amorphous Ru-Pi nanoclusters decorated on PEDOT modified carbon fibre paper as a highly efficient electrocatalyst for oxygen evolution reaction
Amorphous Ru-Pi nanoclusters deposited on PEDOT modified carbon fibre paper electrode have been investigated as a potential oxygen evolution electrocatalyst. CFP/PEDOT/Ru-Pi electrode was prepared by electrodeposition of Ru-Pi nanoclusters on PEDOT decorated CFP using cyclic voltammetry (CV). Field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDS), attenuated total reflection with Fourier-transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD) were used for physicochemical characterization. Linear sweep voltammetric (LSV) studies corroborated that CFP/PEDOT/Ru-Pi has exhibited higher oxidation peak current when compared to other modified electrodes. CFP/PEDOT/Ru-Pi electrode has displayed better catalytic activity towards oxygen evolution reaction at low onset and over potential. The modified electrode has also offered better stability towards the oxidation reaction in phosphate buffer solution (PBS) and the working stability of these electrodes were determined using LSV and CV. 2021 Elsevier B.V. -
Legal conundrums of space tourism
Private commercial space tourism carrying passengers to outer space is no longer a distant or far-fetched fantasy, rather it is at verge of becoming an affordable reality with exponential development in space technology including development of Reusable Launch Vehicle (RLV), increasing involvement of private companies like Virgin Galactic, SpaceX, Blue Origin etc. into research and funding of space tourism explorations and applications. It is also receiving huge attention from the public. These developments reflect the infinite possibilities and inevitability of space tourism in near future. However, space tourism may also pose many critical legal issues which must be addressed to ensure the consistent and sustainable development of space tourism, and to secure the rights of all stakeholders involved including operators, passengers, launching State etc. The research paper would highlight the crucial legal issues associated with the space tourism. The paper would critically analyze the efficiency of the present international space treaties in dealing with these issues. At the end, the paper would also attempt to provide few suggestions and solutions to these legal conundrums relating to space tourism. 2021 IAA -
Plant disease diagnosis and solution system based on neural networks
Plant diseases are one of the major factors affecting crop yield. Early identification of these diseases can improve productivity and save money and time for the farmer. This paper presents a novel technique to diagnose plant diseases using a mobile application. A Convolutional Neural Network (CNN) model was built and trained using MobileNetV2 architecture with the help of image processing techniques and transfer learning. A dataset comprising 87,000 images that contain 38 classes of diseases belonging to 14 different crops was used to train the model. The model achieved an accuracy of 98.69% and a loss of 0.5373. A mobile application was built in Android Studio with the help of a trained model. The mobile application built works without a need for a remote server. The application can identify the disease, gives information regarding the identified disease and also suggests necessary remedies to tackle the disease. 2021, Engg Journals Publications. All rights reserved. -
Rainbow degree-jump coloring of graphs
In this paper, we introduce a new notion called the rainbow degree-jump coloring of a graph. For a vertex v ? V(G), let the degree-jump closed neighbourhood of this vertex be defined as Ndeg [v] = {u: d(v, u) ? d(v)}. A proper coloring of a graph G is said to be a rainbow degree-jump coloring of G if for all v in V(G), c(Ndeg [v]) contains at least one of each color class. We determine a necessary and sufficient condition for a graph G to permit a rainbow degree-jump coloring. We also determine the rainbow degree-jump chromatic number, denoted by ?rdj (G), for certain classes of cycle related graphs. Mphako-Banda E.G., Kok J., Naduvath S., 2021. -
Total induced vertex stress in barbell-like graphs
This paper introduces new parameters called induced vertex stress and total induced vertex stress in G, respectively. For graphs G and H, aspects of the maximum and minimum total induced vertex stress that can be obtained by 1-edge addition and 2-vertex merging are discussed. 2021 Journal of the Indonesian Mathematical Society. All rights reserved. -
The dark side of technology-enabled teaching: Impact of technostress on student performance
This study validates an instrument used to measure technostress creators, technostress support mechanisms, and their negative impact on students' satisfaction and performance. A research model is developed based on the stimulus, organism, and response model to analyse the mediating effect of technostress creators and understand how technostress inhibitors influence students' satisfaction and their performance. A group of 206 students from India pursuing higher education were selected as a sample to validate this model. Technostress creators act as a mediator between technostress inhibitors and students' satisfaction and their performance, while technostress inhibitors positively influence student satisfaction and performance indirectly. Insights from this study will enable higher education institutions to identify the students who are finding technology-based education problematic and help preserve their wellbeing by following supportive strategies to reduce stress and enhance the students' active participation in technology-based education. Copyright 2021, IGI Global. -
Heat transfer optimization of hybrid nanomaterial using modified Buongiorno model: A sensitivity analysis
Sensitivity analysis of the heat transfer rate in the flow of the hybrid nanoliquid C2H6O2?H2O (base liquid) +MoS2?Ag (nanoparticles) over a wedge using the Response Surface Methodology (RSM) is carried out. The nanomaterial is modeled using the modified Buongiorno nanofluid model (MBNM) that considers the major slip mechanisms and the effective properties of the hybrid nanoliquid. Two distinct heat sources- linear thermal heat source and an exponential space-dependent heat source are taken into account. The governing nonlinear two-point boundary-layer flow problem is treated numerically. The effects of pertinent parameters on the flow fields in the boundary layer region are represented graphically with suitable physical interpretations. The exponential heat source and slip mechanisms are used to study the sensitivities of the heat transfer rate. Both heat source mechanisms lead to an improvement in the temperature profile, in which the effect of the exponential space-related heat source is predominant. The Brownian motion parameter was found to be the most sensitive to the heat transfer rate. 2021 -
A Numerical Investigation on Thermal Gradients and Stresses in High Temperature PEM Fuel Cell During Start-up
The High Temperature Polymer Electrolyte Fuel Cell (HT-PEMFC) stacks using polybenzimidazole (PBI) based membranes have an inability to internally heat up at low temperatures to their nominal operating temperature (160C180C) during the start-up process. Several strategies, such as direct electrical heating, coolant/gas channel heating, catalytic hydrogen-oxygen combustion, etc., are proposed in the literature to assist the heating for quick start-up situations. However, little knowledge exists on the transient thermomechanical stresses induced during the start-up heating process due to non-uniformity in heat supply and disparity in thermal properties of the cell components. The objective of the present research is to analyze the thermal gradients and thermal stresses developed in the HT-PEMFC structure during the start-up with various heating methods discussed in the literature, as well as during the cell operation by exploiting the Fluid-Structure Interaction (FSI) approach. The use of polyalkylene glycol (Fragoltherm S-15-A) based Heat Transfer Fluid (HTF) in the coolant channel has substantially improved the start-up time due to the high Nusselt number. However, a significant gradient in temperature distribution is observed during the preheating process, which resulted in great inhomogeneous stresses in the membrane, particularly in the in-plane direction. Interestingly, the degree of uniformity in membrane current density distribution during cell operation is increased. A detailed heat analysis in the cell showed that the heat generated in the cell due to electrochemical reactions is sufficient to raise the cell temperature from 120C to operating temperature in a short time. Being subjected to a compressive stress of above 40 MPa, which is higher than the ultimate strength of a typical acid doped PBI membrane, the electrolyte is the most vulnerable component during the start-up. Hence, to inhibit the concomitant effect on cell performance and degradation, a novel start-up strategy should be implemented. 2021 Elsevier Ltd -
An internet of health things-driven deep learning framework for detection and classification of skin cancer using transfer learning
As specified by World Health Organization, the occurrence of skin cancer has been growing over the past decades. At present, 2 to 3 million nonmelanoma skin cancers and 132 000 melanoma skin cancers arise worldwide annually. The detection and classification of skin cancer in early stage of development allow patients to have proper diagnosis and treatment. The goal of this article is to present a novel deep learning internet of health and things (IoHT) driven framework for skin lesion classification in skin images using the concept of transfer learning. In proposed framework, automatic features are extracted from images using different pretrained architectures like VGG19, Inception V3, ResNet50, and SqueezeNet, which are fed into fully connected layer of convolutional neural network for classification of skin benign and malignant cells using dense and max pooling operation. In addition, the proposed system is fully integrated with an IoHT framework and can be used remotely to assist medical specialists in the diagnosis and treatment of skin cancer. It has been observed that performance metric evaluation of proposed framework outperformed other pretrained architectures in term of precision, recall, and accuracy in detection and classification of skin cancer from skin lesion images. 2020 John Wiley & Sons, Ltd. -
Design of Reconfigurable FRM Channelizer using Resource Shared Non-maximally Decimated Masking Filters
This paper presents a reconfigurable frequency response masking (FRM) wideband channelizer architecture which is characterized by low computational and hardware complexity. The proposed hardware efficient architecture is realized by incorporating resource shared non-maximally decimated filter bank in the implementation of the FRM wideband channelizer structure. The coefficients of the proposed architecture are optimized and made multiplier-free using Pareto based meta-heuristic algorithm in the canonic signed digit (CSD) space for reducing the total power consumption of the architecture. The architecture is finally designed and synthesized using Xilinx Vivado and Cadence RTL Encounter compiler for the area and power analysis and is compared with existing channnelizer architectures. The comparison highlights the advantages of the proposed architecture in terms of hardware complexity, power and workload in realizing sharp wideband channel filters. 2020, Springer Science+Business Media, LLC, part of Springer Nature. -
Transgenders in the Mainstream: Welfare Schemes in KeralaKochi Metro Rail Project, Education Programme, Health Clinics, and Old-Age Pension
Marginalization is the process which inhibits an individual or community from enjoying the rights, privileges, resources or opportunities enjoyed by other members of the society. Of all its marginalized sections, society most often tends to ignore the conditions of transgender persons. The 2011 census reported 480,000 of Indias population as transgender. Kerala pioneered a model for a trans-friendly state1 with the launch of a 10-day-long state-wide survey, which was followed by the introduction of a state policy for transgender individuals, the establishment of a justice board and Indias first transgender school, scholarships for transgender individuals and the introduction of health clinics, old-age pensions and employment for them in the Kochi Metro, as well as various literary, sports and fashion events. This study is an attempt to critically explore the welfare schemes for transgender persons in Kerala amidst recent developments. 2021 SAGE Publications. -
From a recession to the COVID-19 pandemic: Inflation-unemployment comparison between the UK and India
The recession in India and the UK peaked in 2017 due to the implications of new policy initiatives. The outbreak of the COVID-19 pandemic at the beginning of 2020 intensified the crisis, causing a drastic decline in aggregate demand and output. India and the UK have resorted to monetary and fiscal stimulus packages to face the economic crisis. This study investigated the inflation-unemployment dynamics during the recession and COVID-19 times in India and the UK. Using a generalized additive model (GAM), the results of this study revealed that the recession had given way to stagflation in India. In contrast, in the UK, it has led to a more severe recession in the short-run. During the downturn, policy initiatives aggravate the recession and eventually turn to stagflation in India due to inflation caused by the weak supply side. However, in the UK, the policy initiatives during this downturn pushed the economy into a deeper recession due to reduced demand. The outbreak of the COVID-19 pandemic has had a similar recessionary impact on both economies. A time horizon based recovery plan is suggested to help the economies recover from stagflation and even deeper recession. This framework could enable policymakers to choose the right path of recovery within the shortest possible time. 2021 by the author. Licensee MDPI, Basel, Switzerland. -
Review of Neuropsychological and Electrophysiological Correlates of Callous-unemotional Traits in Children: Implications for EEG Neurofeedback Intervention
Conduct disorder is a significant psychiatric disorder of childhood and adolescence. The Diagnostic and Statistical Manual of Mental Disorders, fifth version (DSM-5), added the limited prosocial specifier to identify those individuals who exhibit a more severe pattern of behavior characterized by a callous and unemotional (CU) interpersonal style across multiple settings and relationships. This review has attempted to summarize the relevant research focusing on the significance of CU interpersonal style in the development of psychopathy. The primary focus was on the electrophysiological and neuropsychological correlates of CU traits and their implication on the treatment protocol using neurofeedback training for children with such traits. The source of the literature search was PubMed, which majorly uses the MEDLINE database. The keywords used included CU traits, conduct disorder, child psychopathy, empathy, electrophysiology, criminal behavior, neuropsychology, neurofeedback training, and so on. Studies from the last 15 years were considered for the review. This review revealed that children with conduct disorder and high-CU traits with a combination of reactive and proactive aggression are more likely to develop psychopathy. Evidence suggests that these children have distinct forms of electrophysiological and neuropsychological correlates. However, research in this area is still not conclusive as they yield variation in findings. Studies on the efficacy of neurofeedback training on reducing symptoms such as impulsivity, hostility, and psychopathy indicate that neurofeedback training can be a promising treatment alternative for children with severe conduct disorder. EEG and Clinical Neuroscience Society (ECNS) 2021. -
Death Rituals and Change Among Hindu Nadars in a South Indian Village
This article examines changes in the death rituals performed among Hindu Nadars in a South Indian village. It emphasises the importance of understanding ritual changes within their specific micro-level local contextual framework, including changing social structures at household and village level. This empirical evidence showcases how changing rituals connected to death reflect various adaptations through imitation, substitution and alteration of specific ritual elements and performants. It also identifies emerging class distinctions among Nadars and their connection with changes in rituals associated with death. This analysis of the changes depicts how Nadars use ritual actions in pragmatic ways, symbolically expressing and realising their aspirations for status enhancement through such ritual performances. 2021 SAGE Publications. -
P type copper doped tin oxide thin films and p-n homojunction diodes based on them
P-type copper doped tin oxide (SnO2:Cu) thin films were prepared by chemical spray pyrolysis method on glass substrates for different doping concentrations. Their structural, optical, surface morphological, elemental and electrical studies were investigated. We fabricated two transparent homojunction diodes using optimized sample of SnO2:Cu which are p- SnO2:Cu/n-SnO2 and p-SnO2:Cu/n- SnO2:F.These diodes are reported for the first time by this method. 2021 Elsevier B.V. -
I Can Live Without Banks, but Not Without Banking: Role of Trust on Loyalty and Evangelism
The purpose of this paper is to examine the antecedents of e-banking loyalty and evangelism via threefold construct of WEQUAL (usability, information quality, and service interaction) of public sector banks operating in India. Moreover, it also investigates the mediating role of consumers' trust on the website quality of these banks and their impact on e-banking loyalty and evangelism. The data was collected from 243 respondents through online questionnaire. In order to develop the model and test the hypotheses, partial least square structural equation modeling (PLS-SEM) was done through Smart PLS version 3.2.9. Results assert that website quality of banks positively influences the trust of consumers via usability, information quality, and service interaction. Also, consumer trust plays a mediation role between WEBQUAL constructs and e-banking loyalty and evangelism. 2021 IGI Global. All rights reserved.