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Radiative heat transport and unsteady flow in an irregular channel with aggregation kinematics of nanofluid
In this study, an unsteady free convective heat transfer and the laminar flowof incompressible nanoliquid in a wavy channel subjected to the nanoparticles aggregation effects were studied. For the investigation, ethylene glycol-based nanofluid with titania nanoparticles was used. Here, the role of the nanoparticle aggregation, thermal radiation, applied magnetic field, and internal heat absorption is examined. A semi-analytical solution of the complicated partial differential equation is obtained by the method of regular perturbation. The effect of several parameters on velocity and temperature profile has been studied. In addition, Nusselt number (Nu) and skin friction (Formula presented.) are also examined and analyzed with the help of graphs. It has been observed that the velocity profile enhances with aggregation effect than without aggregation effect. The aggregation effects are minimal for smaller volume fraction of nanoparticles. A reverse trend near the wavy wall is visible for all parameters. The magnitude of velocity decreased as an effect of the applied magnetic field, whilethe magnitude of velocity increased due to radiative heat flux. Furthermore, the heat sink mechanism reduces the magnitude of the nanofluid temperature. 2021 Wiley Periodicals LLC -
Tuning of the surface structure of silver nanoparticles using Gum arabic for enhanced electrocatalytic oxidation of morin
Gum arabic stabilized silver nanoparticles have been used to modify carbon paste electrodes (AgNPs-GA/CPE) for the electrochemical sensing of morin, a flavanoid. The synthesized nanoparticles, before and after modification of electrodes were characterized by UVvisible spectroscopy, X-ray diffraction (XRD), fourier transformation infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential measurements, and thermogravimetric analysis (TGA). The uniform-sized spherical silver nanoparticles have particle sizes less than 10 nm. AgNPs-GA/CPE electrode has shown excellent electrocatalytic activity towards the oxidation of morin at a potential of 0.14 V. The factors influencing the electrochemical determination of morin such as the effect of pH, the effect of scan rate, and the effect of concentration were studied in detail. The linear dynamic range was found to be 0.65 nM to 7.0 nM with a detection limit of 0.216 nM. The developed sensor has been successfully applied for the determination of morin in mulberry leaves and almonds. 2021 The Author(s) -
Heat transfer of nanomaterial over an infinite disk with marangoni convection: A modified fouriers heat flux model for solar thermal system applications
The demand for energy due to the population boom, together with the harmful consequences of fossil fuels, makes it essential to explore renewable thermal energy. Solar Thermal Systems (STSs) are important alternatives to conventional fossil fuels, owing to their ability to convert solar thermal energy into heat and electricity. However, improving the efficiency of solar thermal systems is the biggest challenge for researchers. Nanomaterial is an effective technique for improving the efficiency of STSs by using nanomaterials as working fluids. Therefore, the present theoretical study aims to explore the thermal energy characteristics of the flow of nanomaterials generated by the surface gradient (Marangoni convection) on a disk surface subjected to two different thermal energy modulations. Instead of the conventional Fourier heat flux law to examine heat transfer characteristics, the CattaneoChristov heat flux (Fouriers heat flux model) law is accounted for. The inhomogeneous nanomaterial model is used in mathematical modeling. The exponential form of thermal energy modulations is incorporated. The finite?difference technique along with Richardson extrapolation is used to treat the governing problem. The effects of the key parameters on flow distributions were analyzed in detail. Numerical calculations were performed to obtain correlations giving the reduced Nusselt number and the reduced Sherwood number in terms of relevant key parameters. The heat transfer rate of solar collectors increases due to the Marangoni convection. The thermophoresis phenomenon and chaotic movement of nanoparticles in a working fluid of solar collectors enhance the temperature distribution of the system. Furthermore, the thermal field is enhanced due to the thermal energy modulations. The results find applications in solar thermal exchanger manufacturing processes. 2021 by the authors. Licensee MDPI, Basel, Switzerland. -
Dry Sliding Friction and Wear Performance of HVOF Sprayed WCCo Coatings Deposited on Aluminium Alloy
The tribological behaviour of WCCo Cermet coatings coated on Al6061 alloy was studied in this work. WCCo Cermet coatings have been coated with different thicknesses by changing the amount of the cobalt using HVOF (High velocity oxy fuel technique). The coatings produced have been subjected to microhardness, friction and wear testing. A disc and pin type machine has been used for assessing friction and wears characteristics. The influence on tribological performance of coating thickness and cobalt levels was examined and compared with aluminium alloy. WCCo coating enhanced hardness by 34% and 42% in 100 and 200 micron thicknesses respectively, compared to aluminium alloy. The wear rate and the coefficient of friction are decreased by 48 and 12%, respectively, compared to uncoated aluminium alloy. Both coatings and substrates increase their wear rate and friction coefficient (COF) with the increase in load and sliding speed. Scanning Electron and Confocal microscopy examinations of worn surfaces were carried out to evaluate coating wear processes. 2021, The Institution of Engineers (India). -
Stability and statistical analysis on melting heat transfer in a hybrid nanofluid with thermal radiation effect
The dual solutions for the stagnation point flow in a cobaltCeO2/kerosene hybrid nanofluid with melting heat transfer and thermal radiation are analyzed. The partial differential equations are solved by the conversion of the partial differential equations into nonlinear ordinary differential equations by utilizing suitable scaling group transformations. Numerical solutions are obtained by employing the built-in function in the MATLAB software (bvp4c). Physically recoverable solutions are found employing stability analysis. The factor variables of interest (melting parameter, the nanoparticle volume fraction of cobalt and CeO2) are then further analyzed by utilizing the sensitivity analysis (based on the response surface methodology model) for heat transfer rate, as well as the skin friction coefficient. It is found that the heat transfer and skin friction tend to be significantly higher in a hybrid nanofluid due to the radiation and melting heat transfer. The lower branch is found to be unstable, whereas the upper branch is found to be stable. Also, the heat transfer rate and skin friction coefficient are found to be negatively sensitive toward the melting parameter. The model in this study can be applied for microscopic propulsion systems and the nano-electromechanical systems integrated with a nano-based system. IMechE 2021. -
Privacy breach perceptions and litigation intentions: Evidence from e-commerce customers
This paper examines the formation of litigation intentions among e-commerce customers under the privacy breach due to the influence of antecedents such as vulnerability, social risk, privacy dispositions, effectiveness privacy policy, awareness of data management and moderators such as privacy control beliefs, efficacy in coping and litigation complexity. A structural equation modelling analysis revealed that reasons for privacy breach perceptions are customer dispositions about privacy, anticipated vulnerability due to privacy breach, and social risk related to personal information disclosure. The control beliefs and coping skills of customers under privacy threat positively moderate litigation intentions. Similarly, the task complexity of litigation significantly reduces litigation intentions. 2021 -
High-performance reconfigurable FET for a simple variable gain buffer amplifier design
Design and simulation of variable gain analog buffer amplifier using single gate reconfigurable field-effect transistor (SG-RFET) with strained silicon channel are proposed. The design simplicity makes SG-RFET device a potential candidate compared to the multi-gate RFET devices. The gain of the proposed configuration is varied by tuning the feedback voltage. The voltage gain of the proposed configuration can be tuned from 0.97V/V to 5V/V with an output load of 1 k?. The operational transconductance amplifier (OTA) using the SG-RFET device is used in the proposed buffer amplifier design. 2021 Informa UK Limited, trading as Taylor & Francis Group. -
Probing the effect of newly synthesized phenyltrimethylammonium tetrachloroaluminate ionic liquid as an inhibitor for carbon steel corrosion
The corrosion protection effect of phenyltrimethylammoniumtetrachloroaluminate[PTMA]+[AlCl4]?as an inhibitor was explored in the present work. In this paper, the authors have explored a non-heterocyclicbased ionic liquid as a corrosion inhibitor for metal protection in the acid cleaning process of metal. In particular, a negative ion is designed based onthe lewis acid concept by which it could cover the maximum surface by the bigger molecule size. The inhibition efficiency was found to be steadily increasing as the concentration of the [PTMA]+[AlCl4]? ionic liquids increased.These studies revealed thatthe inhibitor exhibited a remarkable potential for corrosion protection on carbon steel in 1 N HCl solution. Stable corrosion protection efficiency (96%) was achieved for 1.3 mMof inhibitor. The adsorption of the inhibitive molecule was studied by Langmuir adsorption isotherm. The anti-corrosion effect of ionic liquid on the surface protection was revealed by scanning electron microscope (SEM)and lower surface roughness attained at an optimum concentration of inhibitor in atomic force microscope (AFM) analysis. In this study, with the view of the experimental and theoretical investigation (gaseous and aqueous forms of [PTMA]+[AlCl4]? ionic liquid in presence of HCl)was investigated, and finding deduced that the ionic liquid offered maximum dispenses with the heterocyclic group. In addition, to validate the experimental result, dynamic simulation studies were performed in both gaseous and liquid stimulation conditions. 2021 The Author(s) -
Is it morally justified to create disabled designer babies?
This research paper explores the questionwhether it is morally permissible for an auditory impaired parent to create an auditory impaired offspring? It makes an epistemological inquiry into the experiences of persons with auditory impairments to make an informed decision on the question at stake. There is a general attitudinal bias against the disability. On the contrary, arguments have been raised that a parent with auditory impairment may have a moral right and a liberty to have a specially designed deaf baby. It is argued that a deaf parents desire to have a deaf child, stems from their need to relate linguistically and culturally with the child. It is also in the best interest of the child and the parent. Such arguments seem grossly misguided and are often countered with arguments of open future, and the costs of disability. This research paper seeks to inquire into the epistemic challenges in examining the validity and the soundness of these arguments. It engages into the arguments and counter arguments with respect to whether auditory impairment is a disadvantageous condition to find that deafness does involve an element of harm though it is not only and only harm. It argues against the proposition that laws permitting abortion in case of foetal anomaly are eugenic. It uses Kantian theory to delve into the moral permissibility of the use of genetic engineering for the creation of impairment and enhancement. In the light of moral, ethical and jurisprudential considerations it finds that it is morally impermissible to use genetic interventions to create impairments or enhancements, as it strikes at the humanity in the designer babies and uses them as a means for the satisfaction of desires. 2021, The Author(s), under exclusive licence to O.P. Jindal Global University (JGU). -
Synthesis, structural characterization, electrochemical and photocatalytic properties of vanadium complex anchored on reduced graphene oxide
In this work, vanadium complex anchored reduced graphene oxide (rGO-VO) was successfully synthesized by coordination interaction with phenyl azo salicylaldehyde (PAS) coupled trimethoxy silyl propanamine (TMSPA). The physicochemical and microscopic properties of rGO-VO were studied with different analytical techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM) which confirmed the synthesis of rGO-VO. The electrochemical studies of rGO-VO in glassy carbon electrode demonstrated high current density because of the amazing electrochemical properties of rGO. The photocatalytic studies of anchored rGO-VO and VO(acac)2 toward MB dye indicated that anchored rGO-VO with visible light irradiated MB was degraded fast as compared to VO(acac)2. 2021 Taylor & Francis Group, LLC. -
Do Frequency of Visit and Length of Stay Alter Perceived Cognitive Destination Image? A Multivariate Approach
The Indian tourism industry is competing with global destinations through effective and lucrative strategies. Strategic destination branding is one of the finest ways of achieving the frontier. This requires careful analysis of tourists' perception and behavior from time to time and inculcate insights on the branding process. Accordingly, this research work is an extract from a major research that focused on whether the behavioral elements such as tourists' frequency of visit and length of stay to/in the destination influenced the perceived cognitive destination image. Even though literary sources indicated the connection between these factors, a void was identified in terms of the aspects of the cognitive image, specifically in the Indian context. Hence, a district in Tamil Nadu that had high tourist attractions and potentialities to serve distinct tourist motives was chosen for the study. The respondents answered a structured questionnaire that contained the necessary questions and statements on tourists' sociodemographic characteristics, frequency of visit, length of stay, and perception of the cognitive image of the destination. The sample size was rounded to 327 after data cleaning. Simple percentage analysis revealed that the highest percentage of tourists were frequent visitors and stayed in the destination for more than a week. This is a good sign for marketers to increase the tourists' inflow and invest in branding strategies. The multivariate analysis of variance technique of SPSS was employed to analyze the data. The results indicated that despite the frequency of visit and length of stay, some of the cognitive belief aspects remained unaltered. Suggestions were made to the marketers on deploying the cognitive image aspects while designing the advertisement campaigns and including the cognitive image elements in the branding process. Theoretical implications were also indicated on the outcome of this research. Also, limitations were stated in terms of the sample size, research location, and other aspects. Scope for further research was also indicated. 2021, Associated Management Consultants Pvt. Ltd. All rights reserved. -
A new computational technique for the analytic treatment of time-fractional EmdenFowler equations
This paper presents the study of fractional EmdenFowler (FEF) equations by utilizinga new adequate procedure, specifically the q-homotopy analysis transform method (q-HATM). The EF equation has got greater significance in both physical and mathematical investigation of capillary and nonlinear dispersive gravity waves. The projected technique is tested by considering four illustrations of the time-fractional EF equations. The q-HATM furnish ?, known as an auxiliary parameter, by the support of ? we can modulate the various stages of convergence of the series solution. Additionally, to certify the resolution and accurateness of the proposed method we fitted the suitable numerical simulations. The redeem results guarantee that the proposed process is more convincing and scrutinizes the extremely nonlinear issues emerging in the field of science and engineering. 2021 International Association for Mathematics and Computers in Simulation (IMACS) -
INCLUSIVE LAW SCHOOL CLINICS: Institutionalizing Effective and Accountable Justice for All
Poor people are often denied access to the courts due to expensive legal fees. Preventing free access to justice violates a fundamental constitutional principle and universal international norms. The recognition of access to justice and the rule of law as outcomes and facilitators of sustainable development is a unique feature of the 2030 Agenda. This study shows that providing affordable and timely access to justice institutions and legal aid services will help achieve the Sustainable Development Goals (SDG) 16 targets of peace, justice, and strong institutions. Indian law school clinics have a unique opportunity to achieve the goal through institutionalized clinical legal education. The Advocates Act of 1961 requires an amendment to allow law students and faculty to represent pro bono clients. The study infers that completely institutionalizing the law school legal aid clinics as part of clinical legal education is a powerful platform to promote equal access to justice to all. 2021, Dharma Research Association. All rights reserved. -
Entomotoxic proteins of Beauveria bassiana Bals. (Vuil.) and their virulence against two cotton insect pests
Entomopathogenic fungi are widely used as biocontrol agents against several agricultural pests. Among them, Beauveria bassiana is considered the important one against insect and other arthropod pests. The entomotoxic proteins of B. bassiana were extracted by Sephadex G-25 column, and fractionated using HPLC (BBI, BBII and BBIII) and tested against two hemipteran insect pests i.e., Dysdercus cingulatus Fab. and Phenacoccus solenopsis Tinsely (Hemiptera: Pseudococcidae). Results indicated that protein content was higher in fraction BBII than BBI and BBIII. The vibration frequency in FT-IR obtained with a range of 1650 to 1580 cm?1. Bioassays of fractions (I, II and III) reveal that BBII was highly virulent against third nymphal instar of D. cingulatus (LC50 = 800.2 ppm) and adults of P. solenopsis adult (LC50 = 713.3 ppm). Considering the high virulence of BBII subjected to SDS-PAGE, HPLC and MALDI-TOF analyses. Analyses reveals the presence of 174 kDa and designated as BBF2. These results concluded that the entomotoxic protein of B. bassiana can be utilized for management of these investigated hemipreran pests. Further investigations are necessary for the field application of this entomotoxin against these pests or other insect pests. These results also could be helpful for establishing novel biotechnological uses for this fungus. 2021 The Authors -
A study of diesel and Pongamia Pinnata biodiesel combustion in compression ignition engines using zero-dimensional modelling and experimental methods
The present study develops a single-zone zero-dimensional progressive combustion simulation model using Python programming language for compression ignition engines. The model is capable of predicting in-cylinder pressure, heat release rate, engine performance, and emissions characteristics. The numerical model is experimentally validated using resuts from engine testing for diesel, Pongamia Pinnata biodiesel and diesel-biodiesel blends. The chemical composition of fuel is identified using Gas Chromatography-Mass Spectrometry. The values of power output, mean effective pressure and exhaust oxygen concentration are independently obtained from the numerical model and from the experiments. The engine performance is not significantly affected for biodiesel to diesel blending ratio of up to 30%. A higher oxygen concentration in the exhaust gas is observed with increase in blending ratio. The developed numerical model would be useful in studying the performance and emission characteristics for any alternative fuel with known calorific value and chemical composition. 2020 Informa UK Limited, trading as Taylor & Francis Group. -
Changing look AGN Mrk 590: Broad-line region and black hole mass from photometric reverberation mapping
We present the results of photometric reverberation mapping observations on the changing look active galactic nucleus Mrk 590 at z = 0.026. The observations were carried out from 2018 July to December using broad-bandB-,R-, and narrow-band H ? and S ii filters. The B band traces the continuum emission from the accretion disc, the R band encompasses both the continuum emission from the accretion disc and the redshifted H ? line from the broad-line region (BLR), the S ii band contains the redshifted H ? emission and the H ? band traces the continuum emission underneath the S ii band. All the light curves showed strong variation with a fractional root-mean-square variation of 0.132 0.001 in the B band and 0.321 0.001 in H ? line. From cross-correlation function analysis, we obtained a delayed response of H ? line emission to the opticalB-band continuum emission of $21.44^{+1.49}_{-2.11}$ d in the rest frame of the source, corresponding to a linear size of the BLR of 0.018 pc. This is consistent with previous estimates using H ?. By combining the BLR size with the H ? line full width at half-maximum of 6478 240 km s-1 measured from a single-epoch spectrum obtained with the Subaru telescope, we derived a black hole mass of $1.96^{+0.15}_{-0.21}\times 10^8 {\rm M}_{\odot }$. 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society. -
Phytochemical analysis, anti-oxidant properties and pass assisted prediction of biological activity of sargassum wightti j. Agardh, sargassum ilicifolium (turner) C. Agardh and sargassum lanceolatum J. Agardh
The present study was carried out to determine the phytoconstituents and anti-oxidant properties present in the Sargassum wightti, Sargassum ilicifolium and Sargassum lanceolatum using GC-MS analysis and predict the biological activity by PASS prediction. Gas chromatography/mass spectrometry (GC/MS) analysis was performed on Shimadzu GC interfaced with mass spectrometry using SH-RxiTM-5Sil (Shimadzu) column. The spectra of the phytoconstituents were obtained by the PASS version (http:// www.way2drug.com/passonline). The prediction was based on an analysis of the structure-activity relationships (SAR) in the training set containing information on the structure. GC-MS analysis revealed 39 compounds in S. wightti, 60 compounds in S. lanceolatum and 15 compounds in S. ilicifolium. Common compounds found in these three Sargassum species were 1s,4R,7R,11R-1,3,4,7-Tetramethyltricyclo [5.3.1.0(4,11)] undec-2-en-8-one,2,4-Di-tert-butyl phenol, 1-Decanol, 2-hexyl, Hexatriacontyl-trifluoroacetate, Nonyltetradecyl ether, Neophytadiene, Hexadecane. Sargassum species are rich in anti-oxidant, anti-inflammatory, anti-bacterial and anti-viral properties. The present study proved the presence of bioactive compounds and phytochemical compounds in three species of Sargassum available in Indian coastal regions. 2021, Agri Bio Research Publishers. All rights reserved. -
Impact of Technology Readiness and Techno Stress on Teacher Engagement in Higher Secondary Schools
Rapid technology advancements resulted a fundamental shift in the education sector which redefined the teaching-learning process and teacher engagement. Based on numerous studies on work engagement models and technology readiness, this study explores, how the teachers' readiness to embrace educational technologies, impact on teacher engagement. With stratified cluster sampling model, data were collected from principals, managers, students and 122 teaching staff from the Higher Secondary Schools of Kerala participated in this quantitative study using standardized tools. The study affirmed that age has negative relation with technology readiness and teacher engagement shows an organic technology adoption trend than a disruptive style. Teachers were highly engaged with students-colleagues and varied across experience/age groups. Technology readiness factors positively impacted on social engagements with students-colleagues. As education technology usage is exponential, more future research is needed. 2021 Research Group Education and Virtual Learning (GREAV). All rights reserved. -
Improvising data security measures using rajan transform
Data security has always been a concern with the use of a large amount of data in our day-to-day life. There are many methods suggested and presented to secure data during the stages of its preprocessing and post-processing. However, many of them are not following the process of Homomorphism. During the study of Fast Fourier transform (FFT), Hadamard transform (HT) and Rajan transform (RT), this research work encountered a method that uses the cyclic, dyadic and graphical inverse properties of data and encrypts them which makes them homomorphic. This paper is targeting to improvise the data security measures using Homomorphism-based Rajan Transform, a method, which can help in securing data while data processing. The proposed methodology works in such a way that the encrypted data is available for processing without decrypting data into the original form. The performance of the proposed method is described by the efficiency of the algorithm, key size, Block size, and no of rounds required to complete the encryption. It has been found, if we take 512 bits of input data to get 512-bit ciphertext, it takes 9 rounds and generates a 4608-bit key. 2021 Taylor's University. All rights 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.