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Heat transfer simulation of reline flowing in an elliptic shaped duct: A deep eutectic solvent
Deep Eutectic solvents have emerged as promising alternatives to conventional solvents due to their unique properties and applications. The flow of deep eutectic solvents in various industrial processes has garnered significant attention due to their versatile applications in fields ranging from chemical engineering to energy storage. This study presents a comprehensive mathematical model aimed at elucidating the intricate behavior of eutectic solvent flow within an elliptic duct, a geometric configuration relevant to many real-world systems. In this article, the deep eutectic solvent is composed of choline chlorideurea and is also called Reline. The proposed mathematical model accounts for the complex interplay of fluid dynamics, thermodynamics, and elliptic duct geometry. Key components of the model include the Navier-Stokes equations, which describe the fluid flow, coupled with heat transfer equations to account for temperature variations within the system. The model also considers the phase change behavior of the eutectic solvent, which may exhibit solidification or crystallization phenomena under certain conditions. Numerical simulations and analytical solutions are employed to investigate various aspects of eutectic solvent flow within elliptic ducts, such as velocity profiles, pressure distributions, temperature gradients, and phase transition phenomena. The study explores the influence of key parameters, including the Reynolds number, the aspect ratio of the duct, and the thermophysical properties of the eutectic solvent, on the systems behavior. From the results, it was clearly observed that the velocity at the narrow region decreased as the pressure raised and the Reynolds number profile indicated the presence of turbulent flow behavior. 2024 Taylor & Francis Group, LLC. -
Heat transport and stagnation-point flow of magnetized nanoliquid with variable thermal conductivity, Brownian moment, and thermophoresis aspects
The improvement of heat transport is a very important phenomenon in nuclear reactors, solar collectors, heat exchangers, and coolers, which can be achieved by choosing the nanofluid as the functional fluid. Nanofluids improve thermophysical properties; as a result, they have made great progress in engineering, biomedical, and industrial applications. Therefore, a numerical study has been proposed to analyze the flow and heat transport of nanoliquids over an extendable surface near a stagnation point with variable thermal conductivity under the influence of the magnetic field, due to their importance in the engineering field. Nanoliquid attributes explain the Brownian motion and the diffusion of thermophoresis. The effects of the chemical reaction and the uniform internal heat source/heat sink are also considered. The Nachtsheim-Swigert shooting procedure based on the Runge-Kutta scheme is used for numerical calculation. The impact of effective parameters on velocity, temperature, and volume fraction of the nanoparticles is shown in the graphs and reported in detail. The surface criteria are also estimated with respect to the shear stress and the rate of heat and mass transfer. The aspects of the Brownian moment and Lorentz force are positively correlated to the thermal field of the nanoliquid. Also, the variable thermal conductivity aspect favors the growth of the thermal boundary layer. 2020 Wiley Periodicals LLC -
Heat transport in the flow of magnetized nanofluid over a stretchable surface with heat sources: A mathematical model with realistic conditions
Analyzing the heat transport of nanofluids is of prime importance to various industrial and engineering sectors which involves modeling the physical phenomena via highly nonlinear partial differential equations. In this study, the flow and heat transport of a nanoliquid on a bi-directionally elongating surface subject to two different heat modulations (linear temperature-related heat source and space-related exponential heat source) is investigated using the two-component Buongiorno nanoliquid model. The dynamics of the nanoliquid are altered by an external magnetic field applied perpendicular to the sheet. The impact of Brownian motion, Lorentz forces, and thermophoresis are analyzed under the realistic passive control of the nanoparticles. A comparative analysis of the flow over the linear and nonlinear drawn surface is presented. Numeric solutions for the governing partial differential system are obtained through the finite difference method (FDM). Among two types of heat source modulations, the maximum heat transport is observed in the presence of the exponential space-based heat source modulation. The flow and thermal fields are found to advance in the linear elongated surface flow than the nonlinear elongated flow. Furthermore, the random movement of the nanoparticles and the greater magnitude of the Lorentz force have a positive effect on the thermal enhancement in the nanoliquid system. The results of the study have applications in heating/cooling processes, nanoliquid-dependent structures, and thermal systems with stretchable materials. 2021 Wiley-VCH GmbH -
Heat transport of hybrid nanomaterial in an annulus with quadratic Boussinesq approximation
The convective heat transfer of hybrid nanoliquids within a concentric annulus has wide engineering applications such as chemical industries, solar collectors, gas turbines, heat exchangers, nuclear reactors, and electronic component cooling due to their high heat transport rate. Hence, in this study, the characteristics of the heat transport mechanism in an annulus filled with the Ag-MgO/H2O hybrid nanoliquid under the influence of quadratic thermal radiation and quadratic convection are analyzed. The non-uniform heat source/sink and induced magnetic field mechanisms are used to govern the basic equations concerning the transport of the composite nanoliquid. The dependency of the Nusselt number on the effective parameters (thermal radiation, nonlinear convection, and temperature-dependent heat source/sink parameter) is examined through sensitivity analyses based on the response surface methodology (RSM) and the face-centered central composite design (CCD). The heat transport of the composite nanoliquid for the space-related heat source/sink is observed to be higher than that for the temperature-related heat source/sink. The mechanisms of quadratic convection and quadratic thermal radiation are favorable for the momentum of the nanoliquid. The heat transport rate is more sensitive towards quadratic thermal radiation. 2021, Shanghai University and Springer-Verlag GmbH Germany, part of Springer Nature. -
Heat transport of magnetized Newtonian nanoliquids in an annular space between porous vertical cylinders with discrete heat source
A numerical study of MHD natural convection in an upright porous cylindrical annulus filled with magnetized nanomaterial is made by using the specificity of nanoliquids to improve the phenomenon of heat transport. The upper and lower walls are thermally insulated, whereas the outer wall is kept at a lesser temperature. The finite volume method is used to treat the governing equations via computer code with Fortran programming. The results obtained are given for the values of the Rayleigh number between 103 and 106, aspect ratio Ar = 2, radii ratio ? = 2, Hartmann number (0 ? Ha ? 80), Darcy number (10?5 ? Da ? 10?2), porosity ratio (0.1 ? ? ?0.9), and the nanoparticles volume fraction (0 ? ? ? 0.1). The transferred thermal flux, in laminar natural convection, increases with the growth of the nanoparticle concentration, the Darcy number, the porosity, the Rayleigh number and, the length of the source. 2020 Elsevier Ltd -
Heat transport of nano-micropolar fluid with an exponential heat source on a convectively heated elongated plate using numerical computation
Purpose: The study of novel exponential heat source phenomena across a flowing fluid with a suspension of microparticles and nanoparticles towards a convectively heated plate has been an open question. Therefore, the impact of the exponential heat source in the transport of nano micropolar fluid in the existence of magnetic dipole, Joule heating, viscous heating and convective condition effects has been analytically investigated. Influence of chemical reaction has also been exhibited in this discussion. Design/methodology/approach: The leading equations are constructed via conservation equations of transport, micro-rotation, energy and solute under the non-transient state situation. Suitable stretching transformations are used to transform the system of partial differential equations to ordinary. The transformed ODEs admit numerical solution via RungeKutta fourth order method along with shooting technique. Findings: The effects of pertinent physical parameters characterizing the flow phenomena are presented through graphs and discussed. The inclusion of microparticles and nanoparticles greatly affects the flow phenomena. The impact of the exponential heat source (EHS) advances the heat transfer characteristics significantly compared to usual thermal-based heat source (THS). The thermal performance can be improved through the effects of a magnetic dipole, viscous heating, Joule heating and convective condition. Originality/value: The effectiveness of EHS phenomena in the dynamics of nano micropolar fluid past an elongated plate which is convectively heated with regression analysis is for the first time investigated. 2019, Emerald Publishing Limited. -
Heavy metal stress influence the andrographolide content, phytochemicals and antioxidant activity of Andrographis paniculata
Heavy metals (HM) are toxic components present in the earth's crust that can have a negative impact on plants as well as animals. Andrographis paniculata or 'King of bitters' belonging to the family Acanthaceae, is a medicinal herb traditionally used in the treatment of fever, common cold etc. In the present study, the effect of heavy metals (copper, tin and cobalt) on the andrographolide content, biochemical parameters like chlorophyll, carotenoid, protein, Total phenolic content (TPC), Total flavonoid content (TFC) and antioxidant activity in A. paniculata were analysed. Saplings of A. paniculata were treated at 50 and 100 mM concentrations, three different times at a time interval of 7 days. Andrographolide production was found to increase in copper and cobalt treated saplings when compared with the control. From the results, maximum andrographolide concentration was found in the saplings treated with 50 mM copper (8.51 mg/gm of DW) and 50 mM tin (8.10 mg/gm of DW) respectively. 50 mM cobalt treated plants have shown the highest concentration of TPC (17.21 mg/g of extract) and TFC (6.97 mg/gm of extract). Notable variations in other biochemical parameters like total chlorophyll, carotenoid content and antioxidant activities were observed in all treatments compared with the control. Antony & Nagella (2021). This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited (https://creativecommons.org/licenses/by/4.0/). -
Hepatoprotective activity of Peltophorum pterocarpum leaf and bark in the isoniazid and rifampicin-induced hepatotoxic rats
Background: In recent years, various phytomedicines have been used in the treatment of hepatic disorders. The aim of this study is to find out whether Peltophorum pterocarpum bark and leaves can help rats that have been exposed to isoniazid and rifampicin-induced hepatotoxicity. Materials and Methods: The rats were divided into 10 groups each with 6 rats. The liver damage is induced by isoniazid and rifampicin. The leaf and bark of P. pterocarpum extracted with ethanol are freshly mixed in sterile water (100, 200 and 400 mg/kg body weight), and given to rats orally in the early morning as a single dosage per day until the study period. The animals were sacrificed and the tissue and serum samples were collected for further investigations. Results: The liver damage induced by isoniazid and rifampicin altered the various biochemical parameters levels, but after the treatment of P. pterocarpum barks and leaves the levels were significantly altered when compared to the negative control rats. The drug silymarin was used as a standard. Conclusion: The extracts have the protective effect of liver markers and membrane-bound enzymes against the toxin-treated rats. This result highlights the hepatoprotective properties of the leaves and barks of the plant in a similar manner and the formulation (Group 10) have high beneficial effects than other groups. 2024 -
HER2 siRNA Facilitated Gene Silencing Coupled with Doxorubicin Delivery: A Dual Responsive Nanoplatform Abrogates Breast Cancer
The present study investigated the concurrent delivery of antineoplastic drug, doxorubicin, and HER2 siRNA through a targeted theranostic metallic gold nanoparticle designed using polysaccharide, PSP001. The as-synthesized HsiRNA@PGD NPs were characterized in terms of structural, functional, physicochemical, and biological properties. HsiRNA@PGD NPs exposed adequate hydrodynamic size, considerable ? potential, and excellent drug/siRNA loading and encapsulation efficiency. Meticulous exploration of the biocompatible dual-targeted nanoconjugate exhibited an appealing biocompatibility and pH-sensitive cargo release kinetics, indicating its safety for use in clinics. HsiRNA@PGD NPs deciphered competent cancer cell internalization, enhanced cytotoxicity mediated via the induction of apoptosis, and excellent downregulation of the overexpressing target HER2 gene. Further in vivo explorations in the SKBR3 xenograft breast tumor model revealed the appealing tumor reduction properties, selective accumulation in the tumor site followed by significant suppression of the HER2 gene which contributed to the exclusive abrogation of breast tumor mass by the HsiRNA@PGD NPs. Compared to free drugs or the monotherapy constructs, the dual delivery approach produced a synergistic suppression of breast tumors both in vitro and in vivo. Hence the drawings from these findings implicate that the as-synthesized HsiRNA@PGD NPs could offer a promising platform for chemo-RNAi combinational breast cancer therapy. 2024 American Chemical Society. -
Herbal healing traditions: A study of folk medicines used by traditional healers of Sonamukhi block, Bankura district, West Bengal, India
This ethnobotanical study aims to dive into the traditional medicinal practices used by tribals in Sonamukhi Block, Bankura district, West Bengal, India. Focusing on the use of medicinal herbs, the study carefully investigates the intergenerational wisdom kept by traditional healers, who play an important role in healthcare administration. Through conversations with traditional healers and patients, a thorough list of medicinal plants used to treat various diseases has been developed. The study demonstrates that traditional healers successfully use these medicinal plants to produce herbal medications, offering insights into the painstaking process of herbal medicine preparation that was explored in depth during the investigation. These findings highlight the significance of joint efforts to preserve indigenous knowledge and encourage the incorporation of traditional healing techniques into contemporary healthcare. The research study focused on the complicated junction of scientific methodologies and traditional beliefs, indicating the possibility for effective collaboration between scientific institutions and indigenous populations to improve healthcare practices. The studies' thorough examination of medicinal plant usage and herbal medication manufacturing emphasizes the importance of preserving, recording, and using this unique traditional knowledge for the benefit of world healthcare. 2024 Horizon e-Publishing Group. All rights reserved. -
Heteroatom engineered graphene-based electrochemical assay for the quantification of high-risk abused drug oxytocin in edibles and biological samples
The naive detection of scheduled H drug oxytocin is a vital requisite, owing to its deleterious impact on societal affluence prompted by unconstrained usage. Therefore, a reliable, cost-effective, and quick-to-respond analytic technique for this drug is in ample demand. In this work, we report electrochemical detection of oxytocin employing novel nitrogen, phosphorus co-doped coke-derived graphene (NPG) modified electrode. The electro-oxidation behavior of oxytocin was investigated on the NPG modified electrode by square wave stripping voltammetry (SWSV) in 0.1 M phosphate buffer of pH 7. The oxidation peak current was linear in two ranges, spanning from 0.1 nM to 10 nM and 15 nM to 95 nM. The limit of detection at the NPG electrode was calculated to be 40 pM. The practical application of developed sensor for the determination of oxytocin was examined in edible products and body fluids, hence signifying the possibility of having real-time surveillance over its misusage. 2022 Elsevier Ltd -
Heterojunction engineered MWCNT/Ag3PO4 via organic acid and its natural light-assisted photocatalytic efficiency
Compositing photoactive, but unstable semiconductors with low dimensional carbon-based materials and modulating the hetero junction between them can assure more efficient and stable systems for the remediation of severe pollutants. The current study has given emphasis to understand the role of sulfonic acid in making a compact heterojunction between AP and MWCNTs, considering the effective delocalization of carriers and the direct relationship with the photoactivity. The significant reduction in the band gap of AP from 2.320 to 2.0516ev after the introduction of MWCNTs unmistakably confirmed the compatibility between the composite moieties. The intensity of the photoluminescence peak observed at an emission wavelength of 350nm for pure AP was found to be minimized in the composite, which confirms the effective charge delocalization from AP to the conductive MWCNTs. The closest bond distance was observed in the range of 2.3 to 2.5between an O atom of Ag3PO4 and a C atom of CNT, which explains the tight contact between the species. The photoactivity studies unambiguously confirmed the potential of the organic acid at the composite interface as it could accomplish 99% dye degradation within a span of 8min, whilst the system without the organic acid exhibited complete degradation within a span of 60min. The p-XRD analysis of the catalyst recovered from the reaction mixture revealed its high stability. 2023 Elsevier B.V. -
Heuristic and biases related to finanical investment and the role of behavioral finance in investment decisions - A study /
Zenith International Journal Of Business Economics And Management Research, Vol.5, Issue 12, pp. -
HHO-Based Vector Quantization Technique for Biomedical Image Compression in Cloud Computing
In the present digital era, the exploitation of medical technologies and massive generation of medical data using different imaging modalities, adequate storage, management, and transmission of biomedical images necessitate image compression techniques. Vector quantization (VQ) is an effective image compression approach, and the widely employed VQ technique is Linde-Buzo-Gray (LBG), which generates local optimum codebooks for image compression. The codebook construction is treated as an optimization issue solved with utilization of metaheuristic optimization techniques. In this view, this paper designs an effective biomedical image compression technique in the cloud computing (CC) environment using Harris Hawks Optimization (HHO)-based LBG techniques. The HHO-LBG algorithm achieves a smooth transition among exploration as well as exploitation. To investigate the better performance of the HHO-LBG technique, an extensive set of simulations was carried out on benchmark biomedical images. The proposed HHO-LBG technique has accomplished promising results in terms of compression performance and reconstructed image quality. 2023 World Scientific Publishing Company. -
Hi line analysis of Herbig Ae/Be stars using X-Shooter spectra
Herbig Ae/Be stars are intermediate-mass pre-main sequence stars undergoing accretion through their circumstellar disk. The optical and infrared (IR) spectra of HAeBe stars show Hi emission lines belonging to Balmer, Paschen and Brackett series. We used the archival X-Shooter spectra available for 109 HAeBe stars from Vioque et al. (2018) and analysed the various Hi lines present in them. We segregated the stars into different classes based on the presence of higher-order lines in different Hi series. We discussed the dependence of the appearance of higher-order lines on the stellar parameters. We found that most massive and younger stars show all the higher-order lines in emission. The stars showing only lower-order lines have Teff< 12 , 000 K and an age range of 510 Myr. We performed a case B line ratio analysis for a sub-sample of stars showing most of the Hi lines in emission. We noted that all but four stars belonging to the sub-sample show lower Hi line ratios than theoretical values, owing to the emitting medium being optically thick. The Hiline flux ratios do not depend on the stars spectral type. Further, from the line ratios of lower-order lines and Paschen higher-order lines, we note that line ratios of most HAeBe stars match with electron density value in the range of 10 9 10 11 cm - 3 . The electron temperature, however, could not be ascertained with confidence using the line ratios studied in this work. 2023, Indian Academy of Sciences. -
Hierarchical BiFeO3/Cr2CTx MXene composite as a multifunctional catalyst for hydrogen evolution reaction and as an electrode material for energy storage devices
A multifunctional hierarchical Bismuth ferrite/chromium carbide (BiFeO3/Cr2CTx) MXene has been employed as both electrode material for supercapacitors as well as an electrocatalyst for electrocatalytic water splitting. Here, a facile method is suggested for synthesizing Cr2CTx MXene from the chromium aluminum carbide (Cr2AlC) MAX Phase. X-ray diffraction studies, Scanning electron microscopy, and high-resolution transmission electron microscopy indicate that the aluminum atomic layers are removed from Cr2AlC MAX structure. The electrochemical test reveals that the BiFeO3/Cr2CTx MXene composite, which is produced with less Al2O3, performs well in the hydrogen evolution reaction (HER) with a low overpotential of 128 mV in 1 M potassium hydroxide. 53.3 mV dec?1, and 0.16 ? cm?2, respectively, are the values of the calculated Tafel slope and charge transfer resistance. In a dielectrode electrolysis system, BiFeO3/Cr2CTx MXene electrode needs only 1.81 V of cell potential to provide 10 mA cm?2 with long-term stability. The specific capacity of 671.2 C g?1 at a current density of 1 A g?1 is obtained for BiFeO3/Cr2CTx MXene electrode with 90% capacitance retention after 3000 cycles. The potential use of BiFeO3/Cr2CTx MXene towards HER and supercapacitor application is demonstrated by this study, which offers a gentle path for the fabrication of Cr2CTx MXene composites for energy storage and HER applications. 2023 Elsevier Ltd -
Hierarchical porous covalent organic framework-based sensor for the detection of neurodegenerative disorder biomarkers
Guanosine is an essential biomarker that enacts an important role in neuroprotection against brain-related activities, influences the metabolism of fatty acids, and assists in the improvement of the gastrointestinal tract. A facile and selective electrochemical sensor has been developed for the sensing of guanosine based on a hierarchical porous covalent organic framework. Owing to the distinctive 2D porous architecture and ordered framework of TpBD-COF, the irreversible electrooxidation of guanosine occurred at 1.03 V (vs. SCE) in phosphate buffer solution at pH 6. The anodic peak currents under optimal conditions were linear with guanosine concentration within the range of 0.123720 ?M with a LOD of 40.63 nM under various optimal conditions. Moreover, the developed biosensor was used to determine guanosine in pharmaceutical tablets to confirm its potential application in the healthcare industry. 2023 Elsevier B.V. -
Hierarchically nanostructured ZnO with enhanced photocatalytic activity
Hierarchical nanostructures of ZnO are integrated architectures comprising well-ordered nanoscale subunits and excellent photocatalytic properties. In this study, synthesis of ZnO nanoparticles using methods such as co-precipitation, hydrothermal, thermal decomposition, and electrochemical precipitation yielded microsphere, nanorod, pyramid, and nanopetal-like morphologies, respectively. The catalysts obtained were characterized using XRD, IR, SEM-EDX, UVDRS, TGA, PL, and Zeta potential analysis. The XRD spectra confirmed that all the different morphologies of ZnO have hexagonal wurtzite structures The photocatalytic activity of these nanostructures was determined using a dye degradation study on a model pollutant Methylene Blue (MB) under simulated visible light. The kinetic study of the dye degradation reveals that it obeys pseudo-first-order kinetics with a maximum rate constant of 0.01503 min-1. The nanorod structured ZnO particles prepared by the hydrothermal method showed the best catalytic activity. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
High gain ultra wideband fractal antenna
A high gain Compact Octagonal Ultra-wideband Fractal Antenna (COUFA) using the Dual Layer Meta Frequency Selective Surface Reflector (DLMFSSR) is presented in this manuscript. The proposed Frequency Selective Surface (FSS) provides a suitable reflection phase to act as a reflector and is capable of enhancing the gain of the antenna in its wide operating bandwidth. The proposed antenna design provides better impedance bandwidth of 2-10.37 GHz with significant increase in the gain of 0.41-11.83 dB at various resonance frequencies in comparison with the antenna without reflector. The complete antenna with DLMFSSR is designed and simulated using High Frequency Structure Simulator (HFSS). The Proposed antenna, FSS are fabricated and the numerical results for return loss S11, VSWR and gain are demonstrated. Simulation and fabrication results are found to be worthy, which suites the design malleable enough for several modern UWB wireless applications. Copyright 2019 American Scientific Publishers All rights reserved. -
High performance computational method for fractional model of solid tumour invasion
The behaviour of the solid tumour invasion system in the sense of Caputo fractional with time ? and space x is analyzed by the high performance computational method: q-Homotopy Analysis Transform method (q-HATM). The existence of the solutions has been verified with the assist of fixed point theorem and derived numerical solution for different values of ?,?,h. The novel simulation for all cases is explained through figures. We derived that the method is very efficient for analyzing the behaviour of the epidemiological system. 2023 THE AUTHORS