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ZnO doped SnO2 nano flower decorated on graphene oxide/polypyrrole nanotubes for symmetric supercapacitor applications
Due to their high power density, lengthy cyclability, quick charge-discharge rates, and environmentally friendly design, supercapacitors are incredibly effective electrochemical energy storage devices. A lot of work has been progressed in this direction to increase the specific power and cyclic stability of supercapacitor mainly by using various metal oxides with 2D composites and high concentration electrolytes. But, there are some challenging issues like low energy density, high production cost, and short cyclic life. In this work, we aimed to resolve the low energy density and operating voltage of electrodes by selecting multiphase inorganic-organic material with a suitable concentration of electrolyte. To create such supercapacitor electrodes for high energy storage applications, ZnO doped SnO2 nanoflower decorated on graphene oxide/polypyrrole nanocomposite, which are novel materials with large specific surface area and cyclic stability were studied. The electrochemical study of the nanocomposite materials is done by studying the cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance (EIS) techniques. The supercapacitor device fabrication is processed using ZS/GP2 electrode, and the analysis of supercapacitor performance is also studied. As a result, ZS/GP2 nanocomposite showed a good capacitive behavior with a maximum specific capacitance of 392 F g?1 at 75 mV s?1 scan rate with significantly high specific energy and power density of 31.6 Wh kg?1 and 5177 W kg?1, respectively after the 27,000 consecutive charge-discharge (GCD) cycles at the current density of 0.25 A g?1. The results evidence that these hybrid materials are highly promising electrode materials for energy storage applications. 2023 Elsevier Ltd -
An Objective Evaluation of Harris Corner and FAST Feature Extraction Techniques for 3D Reconstruction of Face in Forensic Investigation
3d reconstructed face images are the volumetric data from two dimensions, it can provide geometric information, which is very helpful for different application like facial recognition, forensic analysis, animation. Reconstructed face images can provide better visualization, than a two dimensional image can provide. For a proper 3d reconstruction one of primary step is feature extraction. The objective of this study is to conduct a comprehensive evaluation of two prominent traditional feature extraction techniques, namely Harris Corner and FAST (Features from Accelerated Segment Test), for the purpose of 3D reconstruction of face images in forensic analysis. In this research paper feature extraction was carried out using the Harris corner detection and FAST Feature technique. 3D reconstruction is completed using the retrieved features. In this study a comparative analysis was conducted assessing the aspect ratio, depth resolution. The results of the assessment provide valuable insights into the strengths and limitations of both techniques, aiding researchers and practitioners in selecting the most suitable method for 3D face image reconstruction applications. 2023, Ismail Saritas. All rights reserved. -
Synthesis of novel Se capped polymer photocatalyst mobilized under visible light: Exploration of piezoelectric effect and charge transfer mechanism in polymer matrix
The present study has shown the original and promising usage of zero valent metallic selenium in the photocatalysis process under visible light. Selenium (Se) dispersed into the Polyvinyl Chloride (PVC) and Polyvinylidene Fluoride (PVDF) polymeric solution (Se-PVC/Se-PVDF matrix) by reflux-calcination method. The SEM and TEM results shows Se nanoparticles are well disseminated into the polymer solution and homogenously mixed to avert cluster of particles. The results shows that Se-PVC matrix effectively enhanced the generation rate of photoinduced electrons and reduced transfer resistance endorsed by photoluminescence, transient photocurrent, and electrical impedance spectroscopy techniques. Further, photocatalytic activity studied in presence of potassium iodide (KI) and isopropyl alcohol (IPA). The decrease in photocatalytic activity order is: Se-PVC > Se-PVDF > Se-PVC + KI > Se-PVDF + KI > Se-PVC + IPA > Se-PVDF + IPA systems. The piezoelectricity phenomena and Surface Plasmon Resonance (SPR) effect proposed for Se-PVC/Se-PVDF matrix and correlated with photocatalytic mechanism for the degradation of Methyl Orange (MO). 2023 Elsevier B.V. -
TelsNet: temporal lesion network embedding in a transformer model to detect cervical cancer through colposcope images
Cervical cancer ranks as the fourth most prevalent malignancy among women globally. Timely identification and intervention in cases of cervical cancer hold the potential for achieving complete remission and cure. In this study, we built a deep learning model based on self-attention mechanism using transformer architecture to classify the cervix images to help in diagnosis of cervical cancer. We have used techniques like an enhanced multivariate gaussian mixture model optimized with mexican axolotl algorithm for segmenting the colposcope images prior to the Temporal Lesion Convolution Neural Network (TelsNet) classifying the images. TelsNet is a transformer-based neural network that uses temporal convolutional neural networks to identify cancerous regions in colposcope images. Our experiments show that TelsNet achieved an accuracy of 92.7%, with a sensitivity of 73.4% and a specificity of 82.1%. We compared the performance of our model with various state-of-the-art methods, and our results demonstrate that TelsNet outperformed the other methods. The findings have the potential to significantly simplify the process of detecting and accurately classifying cervical cancers at an early stage, leading to improved rates of remission and better overall outcomes for patients globally. 2023, Universitas Ahmad Dahlan. All rights reserved. -
Structure of molecule, density gradient, orbital locator and reactivity of 5,6-dichloro-1-cyclopentyl-2-(methylsulfinyl)-1H-benzimidazole- potent inhibitor of map kinase
The present work consists of theoretical studies with the DFT technique on the benzo[d]imidazole derivative, 5,6-Dichloro-1-cyclopentyl-2-(methylsulfinyl)-1H-benzimidazole, and its biological evaluation in silico. The molecule is subjected to geometry optimisation and further DFT studies in gas and solvent phases. Upon solvation with polar solvents, gradual variation in properties result. Topological analyses are performed using Multiwfn software (ELF, LOL, RDG and charge transfer) to illustrate the electron density distribution, interactions, and excitation within the title molecule. ADMETLab 2.0, PreADMET, and SwissADME online tools compute the ADMET profile. Select MAP-kinase target proteins are docked against the title molecule using AutoDock Tools and PyMOL. Discovery Studio Visualizer software is run for visualisation and result analysis of the docked ligand-protein complex. 2023 Elsevier B.V. -
Corporate social responsibility: a cluster analysis of manufacturing firms in India
Purpose: This paper aims to identify the corporate social responsibility (CSR) patterns of Indian manufacturing firms using a CSR index based on ISO26000 and Indias National Voluntary CSR Guidelines. Design/methodology/approach: A total of 121 manufacturing enterprises in the national capital region (NCR) were surveyed. The questions related to the involvement of CSR in business strategy, involvement in CSR planning, involvement in environmental activities, involvement in social activities, monitoring, evaluation and involvement in CSR, reporting and policy and deployment of CSR. A two-step cluster analysis using log-likelihood measures was used to identify groupings in the data set based on their performance across the seven issues. Findings: The two distinctive segments identified adopted intermediate CSR activities, and one undertook advanced CSR activities. Research limitations/implications: This study has several limitations. First, the survey data were drawn exclusively from medium-sized enterprises in the NCR. Second, all the indicators in the CSR index were equally weighted. Originality/value: This paper contributes to the literature by grouping manufacturers CSR activities based on seven dimensions suggested in ISO26000 and Indias National Voluntary Guidelines. The results of this study can help managers, boards and regulators better understand CSR and identify ways to improve it further. 2023, Emerald Publishing Limited. -
Exploring the adsorption efficacy of Cassia fistula seed carbon for Cd (II) ion removal: Comparative study of isotherm models
The current study demonstrates the potential of Cassia fistula seed carbon (CFSC), a waste lignocellulosic biomass, to eliminate Cd (II) ion-from saturated liquid samples. The efficient removal of about 93.2% (w/v) of Cd (II) ions from 10 mg/L concentration was achieved within 80 min of treatment. The CFSC dosage of 100 mg/50 mL accounted as optimal for enhanced Cd (II) removal. Cd (II) adsorption onto CFSC was observed to be maximum at pH 6. The investigational trials were assessed with three isotherm models such Dubinin-Radushkevich, Freundlich, and Langmuir. The specifications obtained from this experimental study align well with the Langmuir isotherm model, which describes the maximal adsorption capacity of 68.02 mg/g. Cd (II) adsorption data from this study exhibited the R2 of 0.9 under pseudo-second-order. Maximum desorption (76.3% w/v) was obtained with 0.3 M HCL. This study revealed that thermally activated C. fistula seed carbon (CFSC) can be tuned to be lucrative adsorbent for Cd (II) elimination from water and waste-water. 2023 Elsevier Inc. -
Rayleigh-Bard convection in mono and hybrid nanoliquids in an inclined slot
Linear stability analysis is conducted to investigate the longitudinal and transverse rolls (TRs) generated in Rayleigh-Bard convection in mono and hybrid nanoliquids confined between two infinite inclined parallel slots. Thermophysical properties of six mono nanoliquids and fifteen hybrid nanoliquids are calculated for different volume fractions (0.5%, 1%, 2%) using phenomenological laws and mixture theory. The shooting method is used to solve boundary eigenvalue problems to obtain the eigenvalues for 16 different boundary conditions. It is observed that as the inclination angle is increased, it delays the onset of longitudinal rolls in the case of all boundary conditions. However, it advances the onset of TRs except when the lower plate is adiabatic. The addition of mono and hybrid nanoparticles results in the advancement of the onset of convection. The addition of SWCNT and SWCNT Al 2 O 3 accelerates the onset of convection the most while Cu and Cu-Ag accelerates the onset of convection the least amongst the mono and hybrid nanoparticles considered in the study. 2023 IOP Publishing Ltd. -
Fabrication of silver nanoparticle decorated graphene oxide membranes for water purification, antifouling and antibacterial applications
The quality of portable water is adversely affected by inadequate wastewater treatment, increase in domestic & industrial waste, and microbial contamination of surface water sources. Purification techniques such as sedimentation, precipitation, filtration, and ion exchange can be employed to recover clean water from various impurities. Among these, membrane-based purification methods have become more appealing in recent years due to its cost-effective and energy-saving features. However, fouling is a ubiquitous problem in membrane-based purification technologies, which leads to reduced water permeation and quality. Present study embodies the development of silver decorated graphene oxide coated nylon membrane with remarkable antibacterial and antifouling properties. Antibacterial analysis of bacteria Staphylococcus aureus and Escherichia coli, validates that higher concentration of silver in GO (GO A500) composites hinder the growth of bacteria. The antifouling properties of GO A500 membrane showed flux recovery ratio of 96 % with irreversible fouling ratio of 3 % during the filtration of BSA (Bovine serum albumin) protein. Further fabricated composite membrane exhibited pure water flux of 46.7 L m?2 h?1 with dye removal rate of 95 %, 88 % and 85 % for Congo red, Rhodamine-B and Methylene blue respectively. Catalytic studies conducted on GO A500 membrane demonstrated the efficacy of their antifouling properties. The investigations revealed that the composite (GO A500) membrane has excellent antibacterial and antifouling properties, making it a suitable option for wastewater treatment applications. 2023 Elsevier B.V. -
Synthesis, Mechanical Properties and Thermal Stability of Polydimethylsiloxane Nanocomposites
The polydimethylsiloxane/nano-graphite (PDMS-NG) nanocomposites were prepared via a two rolled mixing mill and subjected to characterization using techniques such as Transmission Electron Microscopy (TEM), stress-strain analysis during elongation, as well as thermal properties including Thermo-Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The transition temperature was observed to be below-70C for PDMS nanocomposites reinforced with Nano-Graphite (NG). The thermogram from the thermo-gravimetric analysis indicated that at 10%, 20%, 30%, and 50% weight loss, the temperatures for PDMS nanocomposites were higher compared to unfilled PDMS. These findings suggest a substantial improvement in the thermal stability of PDMS-NG nanocomposites. 2023, Books and Journals Private Ltd. All rights reserved. -
Newly designed single-stage dual leg DC-DC/AC buck-boost converter for grid connected solar system
This paper proposes a novel single-stage buck-boost inverter based on dual leg. Modulation techniques, working principle, guidelines for components design, and guidelines are discussed and presented. A theoretical concept is initially tested in Simulink platform and practically verified with a test bench model. A practical model is developed to verify the simulation model and tested different modes of operation are analyzed. The main advantages of the proposed work are as follows: The number of passive components is less, switching frequency components are not high so leakage current is very less, and voltage control in a wide range is achieved without using a DC link capacitor. High efficiency can be achieved due to multi-stage operation. This proposed work is suitable for high/low voltage PV-based energy conversion. Electromagnetic interference is also reduced due to continuous input current. 2023 John Wiley & Sons Ltd. -
Jugaad in organizational settings: exploring the Jugaad leadership competencies
The Hindi term 'jugaad' is closely linked to frugal innovation. In resource-scarce environments, organizations can thrive by developing jugaad-related leadership abilities. Previous research on jugaad has focused primarily on individual problem-solving and overlooked the leadership skills necessary to implement it in organizational settings. This study employs a theoretical lens of leadership competency models, interpretive phenomenology, purposive sampling, and an inductive data-driven coding approach to explore the jugaad leadership competencies of 28 Indian business leaders and managers. The study presents the Jugaad Leadership Competency (JLC) model, identifying ten competency clusters exhibited by jugaad leaders. This is the first study to develop a model for jugaad leadership in organizational settings. In environments characterized by scarcity and intense competition, the JLC model can aid individuals and organizations in acquiring the necessary competencies for frugal innovation. The study evaluates the theoretical and practical implications of the findings, their transferability, and limitations and offers suggestions for future research. 2023, Springer Nature Limited. -
COVID-19 pandemic and trade flows: empirical evidence from selected Asian Pacific countries
Purpose: This paper aims to investigate the effects of the COVID-19 crisis on trade flows in Asia Pacific countries and explores the causality between COVID-19-related shocks and trade. Design/methodology/approach: The authors used two novel techniques, namely, two-stage instrumental-variables (2SIV) approach and Juodis, Karavias and Sarafids (JKS) causality test, to examine trade dynamics in the Asia Pacific region during the pandemic. Findings: Using the monthly trade data of 17 Asia Pacific countries between January 2020 and December 2021, the results were threefold. Firstly, the empirical analysis showed that during the COVID-19 crisis, the flow of exports tended to persist idiosyncratically in comparison to the flow of imports. In particular, a specific finding was that the persistence level in exports was about 20%25% higher than that in imports. Secondly, the authors found that the past values of COVID-19 cases and COVID-19 deaths contain information that helps to predict exports/imports over and above the information contained in the past values of exports/imports alone. Finally, the study established that the government response and stringency indexes have a Granger-causal relationship with exports and imports. Research limitations/implications: For the foreseeable future, these findings have significant policy ramifications. Firstly, if a COVID-19 crisis-like situation emerges in the future, it will be critical for countries to maintain their competitiveness throughout the crisis, like the COVID-19 pandemic, while also rebuilding trade relationships wherever possible. Secondly, because information about government responses and measures can also be used to predict future trade flows, prudent management of government responses and stringent measures will be necessary in a crisis like COVID-19 to achieve the optimum level of exports and imports. At the same time, the trading partners should give up the idea of trade protection and focus on finding a way to balance the conflicting needs of imports and exports. Originality/value: To the best of the authors knowledge, the authors, for the first time, used a 2SIV approach and JKS causality test to examine trade dynamics in the Asia Pacific region during the pandemic. In addition, the authors present the first comprehensive analysis of the evolving relationships between export and import flows and governmental policy responses under COVID-19. As a result, it contributes uniquely to both public and international economics. 2023, Emerald Publishing Limited. -
The Champions Boat League A Race to Commercialise Festival Cultures
[No abstract available] -
Identification of Superclusters and Their Properties in the Sloan Digital Sky Survey Using the WHL Cluster Catalog
Superclusters are the largest massive structures in the cosmic web, on tens to hundreds of megaparsec scales. They are the largest assembly of galaxy clusters in the Universe. Apart from a few detailed studies of such structures, their evolutionary mechanism is still an open question. In order to address and answer the relevant questions, a statistically significant, large catalog of superclusters covering a wide range of redshifts and sky areas is essential. Here, we present a large catalog of 662 superclusters identified using a modified friends-of-friends algorithm applied on the WHL (Wen-Han-Liu) cluster catalog within a redshift range of 0.05 ? z ? 0.42. We name the most massive supercluster at z ? 0.25 as the Einasto Supercluster. We find that the median mass of superclusters is ?5.8 1015 M ? and the median size ?65 Mpc. We find that the supercluster environment slightly affects the growth of clusters. We compare the properties of the observed superclusters with the mock superclusters extracted from the Horizon Run 4 cosmological simulation. The properties of the superclusters in the mocks and observations are in broad agreement. We find that the density contrast of a supercluster is correlated with its maximum extent with a power-law index, ? ? ?2. The phase-space distribution of mock superclusters shows that, on average, ?90% of part of a supercluster has a gravitational influence on its constituents. We also show the mock halos average number density and peculiar velocity profiles in and around the superclusters. 2023. The Author(s). Published by the American Astronomical Society. -
New Insights in the Bubble Wall of NGC 3324: Intertwined Substructures and a Bipolar Morphology Uncovered by JWST
We report the discovery of intertwined/entangled substructures toward the bubble wall of NGC 3324 below a physical scale of 4500 au, which is the sharp edge/ionization front/elongated structure traced at the interface between the H ii region and the molecular cloud. The sharp edge appears wavy in the Spitzer 3.6-8.0 ?m images (resolution ?2?). Star formation signatures have mostly been traced on one side of the ionization front, which lies on the molecular clouds boundary. The James Webb Space Telescopes (JWST) near- and mid-infrared images (resolution ?0.?070.?7) are employed to resolve the sharp edge, which has a curvature facing the exciting O-type stars. The elongated structures are associated with the 3.3 ?m polycyclic aromatic hydrocarbon (PAH) emission, the 4.05 ?m ionized emission, and the 4.693 ?m H2 emission. However, the PAH-emitting structures are depicted between the other two. The H2 emission reveals numerous intertwined substructures that are not prominently traced in the 3.3 ?m PAH emission. The separation between two substructures in the H2 emission is ?1.?1 or 2420 au. The intertwined substructures are traced in the spatial areas associated with the neutral to H2 transition zone, suggesting the origin of these structures by thin-shell instability. Furthermore, an arc-like feature traced in the Spitzer 3.6-8.0 ?m images is investigated as a bipolar H ii region (extent ?0.35 pc) at T d ?25-28 K using the JWST images. A massive-star candidate VPHAS-OB1 #03518 seems to be responsible for the bipolar H ii region. 2023. The Author(s). Published by the American Astronomical Society. -
Numerical modeling of novel cage-like cross-linked membranes for enhanced proton conductivity in a high temperature-polymer electrolyte membrane fuel cell
Phosphoric acid (PA)-doped polybenzimidazole (PBI) membranes have encountered several problems associated with high cost, chemical instability, poor solubility in organic solvents, and higher doping level which results in poor mechanical properties and faster degradation of the membrane. Alternative membranes with high proton conductivity and mechanical strength for high-temperature applications are of great interest, one such membrane being cPBI-IL X. The cage-like cross-linked structure of these membranes shows a dual proton transport path due to which proton conductivity is elevated. The ionic liquid content of these membranes improves the PA absorbing capability and shortens the proton transfer path. These membranes exhibit the highest proton conductivity of 13.3 S/m and better durability compared to existing PBI Membranes. A mathematical model is developed and validated versus published experimental results to account for the proton conductivity of these membranes. The developed model is further investigated for a detailed understanding of polarization phenomena and species distribution. 2023 Wiley Periodicals LLC. -
Enhanced supercapacitors and LPG sensing performance of reduced graphene oxide/cobalt chromate pigments for energy storage applications
It is imperative that an initial inquiry be conducted as soon as possible since the production of monolayer of carbon atoms (rGO) composites is the root cause of their poor performance in supercapacitor and LPG sensors. Here, an effort is undertaken to construct a cobalt chromate pigments-reduced graphene oxide (CoCr2O4/rGO) by solution combustion method for the supercapacitor and LPG sensor. The proposed method is efficient and easy in terms of its application to the production of CoCr2O4/rGO polycrystalline composite on a wide scale. Within the scope of this work is an investigation into the improved supercapacitor and LPG sensing behaviour of CoCr2O4/rGO polycrystalline composite. We have implemented a simple method that has been identified for mass-producing reduced graphene oxide. The Solution combustion technique was used, and it was successful in achieving this goal for the very first time. X-ray diffraction technique is used analyse crystallinity, phase, and structural investigation. The nature of gas sensing behaviour with a step function of LPG gas at 500 ppb was studied at room temperature for rGO, The CoCr2O4 pigments and 0.5CoCr2O4+0.5rGo polycrystalline composite samples. The gas response is maximum for 0.5CoCr2O4+0.5rGo polycrystalline composite in the order of 97% in compare with the reduced graphene oxide sample which shows the lowest sensitivity in the order of 26% on exposure of liquified petroleum gas (LPG). The recorded response and recovery times of 0.5CoCr2O4+0.5rGo polycrystalline composite is found to be 40 s and 52 s respectively in comparison to the rGO sample about 58 and 74 s respectively. By adding rGo to the material, the cyclic voltammetry (CV) findings demonstrate improved current density and area of CV loop with increased scan rate. In three-electrode reveals the system, a CoCr2O4-rGo material exhibits a specific capacitance of 226 F/g. Thus, the results reveals that rGo is contributing significantly to the enhancement of a supercapacitor's performance of CoCr2O4. 2023 Elsevier Ltd and Techna Group S.r.l. -
Plant Leaf Disease Classification Using Optimal Tuned Hybrid LSTM-CNN Model
Tomatoes are widely cultivated and consumed worldwide and are susceptible to various leaf diseases during their growth. Therefore, early detection and prediction of leaf diseases in tomato crops are crucial. Farmers can take proactive measures to prevent the spread and minimize the impact on crop yield and quality by identifying leaf diseases in their early stages. Several Machine Learning (ML) and Deep Learning (DL) frameworks have been developed recently to identify leaf diseases. This research presents an efficient deep-learning approach based on a hybrid classifier by optimizing the CNN and LSTM models, which helps to enhance classification accuracy. Initially, Median Filtering (MF) is used for leaf image pre-processing. Then, an improved watershed approach is used for segmenting the leaf images. Subsequently, enhanced Local Gabor Pattern (LGP) and statistical and color features are extracted. An optimized CNN and LSTM are used for classification, and the weights are tuned using the SISS-OB (Self Improved Shark Smell With Opposition Behavior) algorithm. Finally, we have analyzed the performance using various measures. Since we have done segmentation, feature extraction, and optimization improvisations, our proposed methodology results are higher than other available methods and existing works. The results obtained at Learning Percentage (LP) is 90% which is far superior to those obtained at other LPs. The FNR (False Negative Rate) is much lower (0.05) at the 90th LP. The proposed model achieved better classification performance in terms of Accuracy of 97.13%, Sensitivity of 95.09%, Specificity of 95.24%, Precision of 94.31%, F measure of 96.71% and MCC 87.34%. 2023, The Author(s), under exclusive licence to Springer Nature Singapore Pte Ltd. -
Solvent-solute interaction, thermodynamic behaviour, structural, chemical and anti-cancer biological properties of 3(2H)-furanone derivatives
In this work, the structures, reactivities, and electronic and biological properties of the 3(2H)-furanone derivatives, 2-hydroxy-2,5-diphenyl-4-(phenylamino)furan-3(2H)-one (HDPF), 2-methoxy-2,4,5-triphenylfuran-3(2H)-one (MTPF), 3-oxo-2,4,5-triphenyl-2,3-dihydrofuran-2-yl acetate (OTDF), and 2-chloro-2,4,5-triphenylfuran-3(2H)-one (CTPF), are explored via theoretical investigations using DFT (Density Functional Theory) techniques as the main tools for the study. The DFT studies include geometry optimisation, FMO (Frontier Molecular Orbital) analysis, theoretical UV studies, molecular electrostatic potential (MEP) investigations, non-linear optical (NLO) analyses, and the evaluation of thermodynamic parameters. Multiwfn 3.8 software is utilised to conduct the topological analyses. The ADME (Absorption, Distribution, Metabolism, Excretion) profiles are produced with the SwissADME online tool. The target proteins, MCL-1 (Myeloid cell leukemia-1), BCL-2 (B-cell lymphoma-2), and myeloblastin, are docked with the title molecules using AutoDock 1.5.6. 2023 Elsevier B.V.