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Thermophoresis, or thermodiffusion, is becoming a more popular method for investigating the interactions between proteins and ligands due to its high sensitivity to the interactions between solutes and water. Despite its growing use, the intricate mechanisms behind thermodiffusion remain unclear. This gap in knowledge stems from the complexities of thermodiffusion in solvents that have specific interactions as well as the intricate nature of systems that include many components with both non-ionic and ionic groups. To deepen our understanding, we reduce complexity by conducting systematic studies on aqueous salt solutions. In this work, we focused on how guanidinium salt solutions behave in a temperature gradient, using thermal diffusion forced Rayleigh scattering experiments at temperatures ranging from 15 to 35 °C. We looked at the thermodiffusive behavior of four guanidinium salts (thiocyanate, iodide, chloride, and carbonate) in solutions with concentrations ranging from 1 to 3 mol/kg. The guanidinium cation is disk-shaped and is characterized by flat hydrophobic surfaces and three amine groups, which enable directional hydrogen bonding along the edges. We compare our results to the behavior of salts with spherical cations, such as sodium, potassium, and lithium. Our discussions are framed around how different salts are solvated, specifically in the context of the Hofmeister series, which ranks ions based on their effects on the solvation of proteins. [ABSTRACT FROM AUTHOR]

Building on recent simulation work, it is demonstrated using molecular dynamics simulations of two-component fluid mixtures that the chemical contribution to the Soret effect in two-component nonideal fluid mixtures arises due to differences in how the partial pressures of the components respond to temperature and density gradients. Further insight is obtained by reviewing the connection between activity and deviations from Raoult's law in the measurement of the vapor pressure of a liquid mixture. A new parameter γ s S , defined in a manner similar to the activity coefficient, is used to characterize differences deviations from "ideal" behavior. It is then shown that the difference γ 2 S − γ 1 S is predictive of the sign of the Soret coefficient and is correlated to its magnitude. We hence connect the Soret effect to the relative volatility of the components of a fluid mixture, with the more volatile component enriched in the low-density, high-temperature region, and the less volatile component enriched in the high-density, low-temperature region. Because γ s S is closely connected to the activity coefficient, this suggests the possibility that measurement of partial vapor pressures might be used to indirectly determine the Soret coefficient. It is proposed that the insight obtained here is quite general and should be applicable to a wide range of materials systems. An attempt is made to understand how these results might apply to other materials systems including interstitials in solids and multicomponent solids with interdiffusion occurring via a vacancy mechanism. [ABSTRACT FROM AUTHOR]

We have studied diffusion and thermodiffusion in the ternary system polystyrene + toluene + cyclohexane over the entire composition range of the binary solvent toluene + cyclohexane and for polymer concentrations up to 0.1 mass fractions by multi-color optical beam deflection. The polystyrene molar masses were 4.88 and 17.90 kg/mol. The inversion problem of the contrast factor matrix could be avoided by reasonable a priori assumptions about the diffusion eigenvectors. The fast mode of the bimodal dynamics is attributed to the interdiffusion of the two solvents at constant polymer concentration, whereas the slow mode is due to the diffusion of the polymer with respect to the binary solvent. The amplitude of the fast mode vanishes in the pure toluene and the pure cyclohexane limits of the mixed solvent. The amplitude of the slow mode increases with polymer concentration. The composition and temperature dependence of the slow diffusion eigenvalue, the hydrodynamic correlation length, and the Soret coefficient of the polymer reflect the transition from a good to a theta solvent with increasing cyclohexane content and with decreasing temperature. Due to cross diffusion, cyclohexane reverses its migration direction between the fast and the slow mode, leading to a positive thermodiffusion but a negative Soret coefficient. The polymer thermodiffusion coefficients during the slow mode vary by approximately a factor of two, depending on the solvent composition. Rescaling with the solvent viscosity collapses all data onto a single master curve with an extrapolated value of ηDT ≈ 6 × 10−15 Pa m2 K−1 in the dilute limit. This value is well known from various other binary polymer/solvent mixtures. [ABSTRACT FROM AUTHOR]

The Soret effect, temperature gradient driven diffusion, in silicate melts has been investigated intensively in the earth sciences from the 1980s. The SiO2 component is generally concentrated in the hotter region of silicate melts under a temperature gradient. Here, we report that at ultra-high temperatures above ∼3000 K, SiO2 becomes concentrated in the colder region of the silicate melts under a temperature gradient. The interior of an aluminosilicate glass [63.3SiO2–16.3Al2O3–20.4CaO (mol. %)] was irradiated with a 250 kHz femtosecond laser pulse for local heating. SiO2 migrated to the colder region during irradiation with an 800 pulse (3.2 ms irradiation). The temperature analysis indicated that migration to the colder region occurred above 3060 K. In the non-equilibrium molecular dynamics (NEMD) simulation, SiO2 migrated to the colder region under a temperature gradient, which had an average temperature of 4000 K; this result supports the experimental result. On the other hand, SiO2 exhibited a tendency to migrate to the hotter region at 2400 K in both the NEMD and experimental study. The molar volume calculated by molecular dynamics simulation without a temperature gradient indicates two bends at 1650 and 3250 K under 500 MPa. Therefore, the discontinuous (first order) transition with coexistence of two phases of different composition could be related to the migration of SiO2 to colder region. However, the detailed mechanism has not been elucidated. [ABSTRACT FROM AUTHOR]

Temperature gradients induce mass separation in mixtures in a process called thermal diffusion and are quantified by the Soret coefficient ST. Thermal diffusion in fluid mixtures has been interpreted recently in terms of the so-called (pseudo-)isotopic Soret effect but only considering the mass and moment of inertia differences of the molecules. We demonstrate that the first moment of the molecular mass distribution, the mass dipole, contributes significantly to the isotopic Soret effect. To probe this physical effect, we investigate fluid mixtures consisting of rigid linear molecules that differ only by the first moment of their mass distributions. We demonstrate that such mixtures have non-zero Soret coefficients in contrast with ST = 0 predicted by current formulations. For the isotopic mixtures investigated in this work, the dependence of ST on the mass dipole arises mainly through the thermal diffusion coefficient DT. In turn, DT is correlated with the dependence of the molecular librational modes on the mass dipole. We examine the interplay of the mass dipole and the moment of inertia in defining the isotopic Soret effect and propose empirical equations that include the mass dipole contribution. [ABSTRACT FROM AUTHOR]

The usage of nanoparticles is effectively enhanced in industries and technologies because of their intensified thermal performance. Nanomaterials innovatively play a significant role in technological applications such as biosensors, the petroleum related industry and biofuels. Due to such exceptional performance of nanomaterials, the magneto-hydrodynamics squeezed nanofluid flow is examined through the parallel walls. The transportation phenomenon of heat and mass with viscous dissipation and double stratification is also investigated under Cattaneo–Christov phenomenon. The constitutive equations (PDEs) are transmuted with precise similarity variable into dimensionless equations (ODEs). The acquired ODEs are evaluated through the assistance of Homotopic technique. The impacts of the emerging parameters are described graphically on the concerned profiles. The graphical discussion clarifies that both stratification parameters diminish both profiles (thermal & solutal). Concentration field is decreased by the thermophoresis parameter. The relaxation time parameters decrease the heat and mass transport. Moreover, both Brownian and thermophoresis parameters raise the temperature. [ABSTRACT FROM AUTHOR]

Field-controlled micromanipulation represents a pivotal technique for handling microparticles, yet conventional methods often risk physical damage to targets. Here, we discovered a completely new mechanism for true noncontact manipulation through photothermal effects, called thermal-optical tweezers. We employ a laser self-assembly photothermal waveguide (PTW) for dynamic microparticle manipulation. This waveguide demonstrates superior photothermal conversion and precision control, generating a nonisothermal temperature field. The interaction of thermal convection and thermophoresis within this field creates a microfluidic potential well, enabling noncontact and nondestructive particle manipulation. By varying the path of PTWs in lithography and manipulating laser loading modes, diverse manipulation strategies, such as Z-shaped migration, periodic oscillation, and directional transport, are achievable. Our innovative noninvasive micromanipulation technology minimizes not only physical damage to target objects but also enables precise and diverse manipulation of micro entities, opening up new avenues for the photothermal control of cells and biomolecules. [ABSTRACT FROM AUTHOR]

The Soret effect, also known as thermal diffusion, plays a crucial role in the phenomenon of double diffusion convection in liquids. This study investigates Soret-driven convection within a vertical double-diffusive layer of Maxwell-Cattaneo (M-C) fluids, where the boundaries maintain constant temperatures and solute concentrations that are distinct from each other. The heat transfer equation for Maxwell-Cattaneo fluids is governed by a hyperbolic rule of heat conduction, rather than the typical Fourier parabolic one. The Chebyshev collocation method is employed to solve the corresponding stability eigenvalue problem. The neutral stability curve shows significant fluctuation responses due to the M-C effect. When the Cattaneo number (C) reaches 0.02, multiple local minima appear in the critical Grashof number (Gr). The instability the thermal convection is found to be amplified by the combined effects of Maxwell-Cattaneo and Soret, along with the Grashof number, while the double diffusion effect appears to suppress the instability of convective system. The influence of Soret effect on convective instability will diminish dramatically as the Gr number rises above 8200. [ABSTRACT FROM AUTHOR]

Manufacturing of several products with better quality and features in industries depends upon the cooling processes. Based on the thermal properties, this research aims to investigate the effect of dissipative heat in non-Newtonian Jeffrey nanofluid flow along horizontal channels embedded in a porous matrix. Due to cross-diffusion, the time-dependent electrically conducting fluid presents the role of Brownian motion and thermophoresis. Further, the conjunction of binary chemical reactions encourages the flow phenomena. The appropriate choice of the similarity variables helps to transform a dimensional system of the governing equations into their non-dimensional form. Further, the shooting-based Runge–Kuta–Fehlberg method is used to solve the transformed governing equations. The structural behaviour of the characterising constraints is presented via graphs and described briefly. The validation with the earlier result is presented in a particular case showing a good correlation. [ABSTRACT FROM AUTHOR]

The main motivation behind this numerical analysis is to disclose the salient magneto-thermo characteristic features of two-dimensional viscous incompressible magnetized Soret and Dufour effects on the boundary layer flow of Walter’s-B fluid over a stretching sheet under the influence of viscous dissipation. The novel physical effects such as nonuniform heat source/sink and magnetic Ohmic heating are included in the governing equations. Further, prescribed surface temperature condition is introduced in the boundary conditions to describe the thermal transport features. However, the deployed non-Newtonian Walter’s-B fluid rheology model finds its innumerable applications in numerous areas of science and engineering including electronic cooling, polymer processing, nuclear reactor cooling, extraction of polymer sheet, plastic sheet drawing, chemical engineering, metallurgy, injection molding and many more. Therefore, authors have motivated with these applications and advantageous of considered fluid model. Hence, an effort is made to describe the dynamic characteristic features of non-Newtonian Walter’s-B rheology model about a stretching sheet. However, present physical flow model produces highly nonlinear coupled two-dimensional partial differential equations and which are not acquiescent to available analytical methods. Owing to this, a robust MATLAB-based BVP4C technique is deployed to produce the appropriate numerical solutions through suitable similarity transformations. The graphical representations of velocity, temperature and concentration profiles along with skin-friction coefficient, Nusselt and Sherwood numbers are presented. Magnifying magnetic number decays the velocity profile and enhances the thermal and concentration fields. Rising viscoelastic parameter diminishes the thermal and concentration fields and magnifies the velocity field. Rising the radiation parameter diminish the thermal field. Magnifying Soret number raises the concentration field. Rising the space and temperature dependent heat source/sink coefficient amplifies the thermal diffusion field. Magnifying Dufour and Eckert numbers amplifies the thermal field. Finally, the guarantee and accuracy of the investigated problem is presented through a comparison with previous studies. [ABSTRACT FROM AUTHOR]

Summary: Plant leaf temperatures can differ from ambient air temperatures. A temperature gradient in a gas mixture gives rise to a phenomenon known as thermodiffusion, which operates in addition to ordinary diffusion. Whilst transpiration is generally understood to be driven solely by the ordinary diffusion of water vapour along a concentration gradient, we consider the implications of thermodiffusion for transpiration.We develop a new modelling framework that introduces the effects of thermodiffusion on the transpiration rate, E.By applying this framework, we quantify the proportion of E attributable to thermodiffusion for a set of physiological and environmental conditions, varied over a wide range.Thermodiffusion is found to be most significant (in some cases > 30% of E) when a leaf‐to‐air temperature difference coincides with a relatively small water vapour concentration difference across the boundary layer; a boundary layer conductance that is large as compared to the stomatal conductance; or a relatively low transpiration rate. Thermodiffusion also alters the conditions required for the onset of reverse transpiration, and the rate at which this water vapour uptake occurs. See also the Commentary on this article by Vesala, 243: 1281–1283. [ABSTRACT FROM AUTHOR]

This article deals with the effects of thermophoresis on thermosolutal mixed convection in a vertical wavy porous cavity. Three distinct flow features are chosen by changing the directions of the moving horizontal borders. A nonuniform temperature, as well as concentration distributions, are introduced to the bottom wall while keeping cold temperature and low concentration for the other walls. The governing equations are modeled to describe thermosolutal phenomena. These equations are solved by reconstructing a recently developed compact scheme. Furthermore, the significance of well-defined parameters influencing the fluid rotation and thermosolutal transfer, namely Richardson number ( 0.01 ≤ Ri ≤ 100 ), Buoyancy ratio (N = 1), number of undulations ( 0 ≤ d ≤ 2 ) of the wavy walls, Lewis number ( 1 ≤ Le ≤ 10 ), thermophoretic coefficient ( 0.0 ≤ K T ≤ 1.0 ), Darcy number ( 0.001 ≤ Da ≤ 0.1 ), and porosity of the porous medium ( 0.1 ≤ ε ≤ 1.0 ) are performed generously. Results are displayed in terms of streamlines, isotherms, iso-concentrations, Nusselt, and Sherwood numbers to evoke the thermosolutal phenomena for various physical parameters. It is observed that thermophoresis is effective in certain circumstances. In addition, heat and mass transfer enhancement is noted with decreasing Richardson number while heat and mass transfer reduction is noted with increasing undulation number of the wavy walls. We have noticed that for the change in Le from 1 to 10, heat transfer is diminished up to 2.91% in Case-1, 3.03% in Case-2, and 2.20% in Case-3 while mass transfer is enhanced by 162.85% in Case-1, 164.05% in Case-2, and 87.03% in Case-3. [ABSTRACT FROM AUTHOR]

The current study analyses the entropy of nanofluid flow over three different geometries with thermophoretic particle deposition and thermal radiation. It is essential while considering heat exchangers, transpiration, fiber coating, and other similar processes, to have a solid understanding of the transfer of both heat and mass that occurs during MHD flows across three dissimilar shapes. A mathematical model will be utilized to explore magnetohydrodynamic flows including energy transfer with heat and mass variations. In this model, some of the innovative concepts include thermophoresis, Brownian motion, the Cattaneo–Christov dual flux with the application of an external magnetic field, and the entropy generation effect are considered. By the appropriate similarity transformations, fundamental PDE's converted into ODE's. To solve these ODE's, the Runge–Kutta fourth order is used along with the shooting technique. The results are displayed in graphs and tables. It is observed that the velocity gets decreases with the increase of the porous parameter and magnetic field and gets stronger with the increase of the Grashof number. The temperature increases with an increase in the magnetic field, radiation parameter, Brownian motion parameter, and thermophoresis parameter. Concentration increases with the increase in a magnetic field and Brownian motion parameter but reduces with the increase of other parameters. Entropy generation gets enhanced with an increase in the magnetic field, temperature difference, concentration difference and diffusion parameters. When a flow is directed through geometries the heat and mass transfer rates are both affected by a parameter known as the thermal relaxation parameter. The influence of skin friction, Nusselt number and Sherwood number were analyzed and results were discussed. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing trend in modern engineering systems to integrate electromagnetic features with bio-convection phenomena. This integration has found applications in various fields such as materials processing, robotics, nano-sensors, and computational biology. Inspired by these advancements, a computational simulation is presented to study the steady bio-convection thermo-solutal flow of a Casson nano-fluid, which is a visco-plastic fluid. The simulation takes into account factors such as thermal radiation, heat generation, Soret and Dufour effects, chemical reaction, and convective boundary conditions. It also considers the presence of gyrotactic microorganisms. To model the Casson nano-fluid, a revised Casson model is implemented using the Buongiorno nanoscale formulation. The boundary layer concept is used to derive the fundamental conservation partial differential equations for mass, momentum, energy, solute concentration, and microorganism number density, along with appropriate boundary conditions. The model is then transformed into a system of coupled nonlinear ordinary differential equations using suitable transformations. Numerical solutions are obtained using the built-in method in a Mathematica. The results are presented graphically to provide a visual representation of the flow parameters. The main findings are summarized in the conclusion section. [ABSTRACT FROM AUTHOR]

Asphaltene deposition may pose serious challenges to flow assurance of crude oil in well columns. Different aggregation kinetics would partly be responsible for asphaltene particle growth ending in deposition on the surface of well columns. This work primarily investigates the thermophoretic deposition velocity caused by temperature gradients inside well columns for various asphaltene aggregation kinetics, including crossover behaviour, sedimentation, reaction-limited aggregation (RLA), and diffusion-limited aggregation (DLA). To do so, the experimental observations of size distribution for a live crude oil was performed at 80 °C and pressure range of 4500–5500 psia. Moreover, various patterns of different size distributions were gathered from the literature for the sake of comparison. Next, a well column in southern Iran was selected to study the kinetic behaviour of thermophoretic velocity of deposition, with a difference between geothermal and static temperatures of around 5 to 50 °C. The non-isothermal deposition velocity was shown to decrease from the top to the bottom of the well column, according to the findings of the study. The results also revealed that the thermophoretic velocity decreases as particle size increases and vice versa. This was confirmed by examining a comparably large range of asphaltene particle sizes, ranging from approximately 100 nm to roughly 9 µm. Practical implications of these findings were also discussed which would provide guidance for mitigation of asphaltene deposition in well columns. [ABSTRACT FROM AUTHOR]

AbstractThe free convective, unsteady, two-dimensional (2D) magnetohydrodynamic (MHD) Darcy–Forchheimer Casson fluid flow via a vertical stretching sheet containing gyrotactic microorganisms was the novel aspect of this investigation. We rewrote the collection of partial differential equations (PDEs) as nonlinear ordinary differential equations (ODEs) by considering an appropriate similarity variable. We solved the overhaul of nonlinear ODEs using MATLAB’s bvp4c approach. This study rigorously investigates the significance of gyrotactic microorganisms for Casson fluid motility. Additionally, this work investigates the impact of various parameters, including magnetic parameters, thermophoresis, Brownian motion, and radiation parameters, on temperature, motile microorganisms, velocity, and concentration profiles. We use graphs to illustrate the outcomes of various fluid flow parameters. Numerical tables display the effects of different parameters on skin friction, Sherwood number, Nusselt number, and the quantity of motile microorganisms. The unsteady parameter causes a drop in the velocity, temperature, concentration, and the density profile of microorganisms. Additionally, the Casson parameter leads to a decrease in the flow profile, while simultaneously increasing the heat, concentration, and microorganism density profiles. The microorganism density profile decreases as the bioconvection Schmidt number, Peclet number, and motile microbe parameter increase. We deem the new results extremely satisfactory when compared to earlier research. The fields of environmental remediation, biomedical sciences, and engineering may find this examination useful. [ABSTRACT FROM AUTHOR]

The pivotal role of Brownian and thermophoresis in investigating the flow characteristic of polar nanofluid is important nowadays due to various engineering applications. The enhanced thermal and transport properties in the field of biomedical nanomedicine for hyperthermia treatments, and for enhancing the efficiency of heat exchange processes in cooling electronic devices, heat exchangers, and automotive engines the use of Brownian and thermophoresis is important. Therefore, the present study reveals the importance of Darcy–Forchheimer inertial drag combined with the space‐ and temperature‐dependent heat generation/absorption on the flow of polar nanofluid over an elongating surface. The surface is considered to be permeable for which the hydromagnetic flow in the presence of thermal radiation specifically, Brownian and thermophoresis affects the flow phenomena significantly. The proposed flow model designed with the aforementioned physical properties is standardized into the set of nonlinear ordinary equations by the implementation of suitable similarity rules. Further, the characteristics of various physical quantities are deployed by solving the system by using traditional Rung–Kutta fourth‐order technique. Further, the analysis of several factors is deployed briefly via graphically, and simulation of rate coefficients is presented through tables. The important outcomes of the study are deployed as the inclusion of thermal and solutal buoyancy enhances the velocity distribution, whereas reverse impact is observed for the increasing inertial drag. Also, space‐ and temperature‐dependent heat source augments the temperature profile but Lewis number decelerates the fluid concentration significantly. [ABSTRACT FROM AUTHOR]

Passive systems that need exceptional apparent geometries, thermal packaging, or fluid additives. In passive procedures, a number of foremost efforts have been conducted. The passive methods are divided into two groups: geometry modification (e.g. nano/microchannels) and solid additives (e.g. micro/nano solid particles). In a recent development in microfabrication – the development of fabrication of minuscule buildings of micrometer measures – a variation of microstrategies including heat transfer have been industrialized. Viewing this, the heat and mass transfer characteristics of a free convective Casson fluid over an elastic stretching surface are numerically studied. Thermal radiation and non-Fourier flux are incorporated in the energy to balance the transformation. Similarity transformations are used to translate partial differential equations relating to momentum, diffusion, and energy into nonlinear ordinary differential equations. The shooting approach is used to achieve numerical solutions to these equations. The effect of various physical pertinent parameters including thermal radiation parameter, Brownian motion, thermophoresis, suction, curie parameter, thermal and diffusion buoyancy forces, thermal relaxation, stretching, or shrinking parameters on the concentration and temperature profiles is investigated. It is observed that the nonlinear case has highly mixed performance when compared to the linear case of temperature and concentration fields. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids are a type of nanofluid that is created by combining two different types of nanoparticles with a traditional fluid. These nanofluids have unique physicochemical properties that make them more effective at transferring heat than traditional nanofluids. This research paper focuses on predicting thermal and energy transport in non-Newtonian biomagnetic hybrid nanofluids that contain gold and silver nanoparticles, using Gaussian process regression (GPR). The study uses blood as the traditional fluid and incorporates the effects of thermal radiation, thermophoresis, Brownian motion and activation energy into the model equation. The governing nonlinear partial differential equations are simplified to a set of ordinary differential equations using similarity replacements. The shooting method, along with the Runge–Kutta-Fehlberg fourth–fifth-order scheme, is used to solve the transformed equations using MATLAB. The results of the study are presented through figures and tables, which include the coefficient of skin friction, Nusselt number, Sherwood number and motile microbe's flux, illustrated with surface plots. The GPR model is developed using four basic function kernels (squared exponential, exponential, rational quadratic and matern32 functions) and evaluated using statistical indicators such as RMSE, MSE, MAE and R. The predicted results and simulated numerical values are in good agreement with the coefficient of determination (R2) of 0.999999 for all parameters. The study also finds that GPR models with exponential kernel functions outperform other kernel functions in both the Oldroyd-B and Casson hybrid nanofluid data sets. However, the findings indicate that nanofluids and hybrid nanofluids have superior thermal qualities and stability, making them promising candidates for various thermal applications including solar thermal systems, automotive cooling systems, heat sinks, engineering, medical areas and thermal energy storage. [ABSTRACT FROM AUTHOR]

The current study presented here demonstrates the magnetohydrodynamics (MHD) Casson fluid flow within an infinite vertical plate with consequences of Brownian, thermophoresis, and chemically responsive systems. The governing equations are numerically computed by employing a sixth-order Runge–Kutta (R–K) algorithm, whereas Nachtsheim–Swigert (N–S) shooting iteration technique has been used as the main tool for calculating the current statement. The novelty of this study is dealing with the impression of Brownian and thermophoresis effect using shooting technique. The nonlinear governing problems have been transformed into coupled nonlinear ordinary differential equations using a suitable transformation. Numerical simulation is presented for the various interesting profiles. The velocity, temperature, and concentration profiles along with skin fraction, Nusselt, and Sherwood number take into account with the varying contributions of the parameters and deployed through graphs and tables. However, one of the current study's key findings is that skin friction improves with expanding values of the thermal convective parameter while diminishing with increasing values of the Casson term, magnetic factor, and Eckert number. The current research has an enormous demand for Brownian and thermophoresis effects within the fields involving cosmology, power systems, ionized studies, and nanotechnology. [ABSTRACT FROM AUTHOR]

The study deals with the bio-convective induced magneto-hydrodynamics (MHD) flow of non-Newtonian fluids with the simultaneous effect of multiple slips, heat source/sink, and linear thermal radiation, along with the Soret effect. The novelty of the present study is to analyze the impact of linear thermal radiation, bio-convection Lewis number and Soret parameter on velocity, induced magnetic field, and concentration. For this the flow for Maxwell and Casson fluids were considered and discussed separately, whereas a single governing momentum conservation equation was constructed by combining these two flow models. The governing equations were transformed by using similarity transformation. The transformed equation was solved by using MATLAB "BVP4C" solver. The transformation contributed various parameters such as the Soret parameter, Bioconvective Lewis number, Peclet Number, Radiation parameter, and Schmidt number. The effect of such parameters on momentum, induced magnetic field (i.m.f), temperature, and concentration were studied. The results depicted that the rise in the value of Nr, the temperature of the fluid were increased. However, the concentration of the microorganism declined with the rising value of chemical reaction parameter in both the Maxwell and Casson fluid. The observation also revealed that the velocity optimizes with the rising value of Sr, due to the hike in the concentration of the fluid. [ABSTRACT FROM AUTHOR]

This study investigates the dynamics of heat and mass transfer, focusing on the impact of nonlinear convection and thermophoresis in the flow of viscous nanofluid towards a shrinking sheet embedded with a porous matrix. To facilitate understanding of the flow behavior, the study employs similarity variables to simplify the resulting nonlinear partial differential equations. Numerical analysis utilizing the collocation method with Legendre polynomials as basis functions reveals distinct distributions of velocity, temperature, and concentration. The results demonstrate that the dimensionless suction coefficient amplifies nanoparticle volume fraction and momentum along the stretching surface. In addition, an increase in internal frictional force leads to heightened injection of heat energy, accelerates the temperature field, and impedes nanoparticle diffusion due to heat absorption. Elevation of convection terms augments momentum, reduces energy dispersion, and enhances nanoparticle diffusion. Moreover, an increase in the dimensionless Eckert number (Ec) correlates with intensified energy and diminished diffusion concentration of the nanoparticle volume fraction [ABSTRACT FROM AUTHOR]

The high-temperature particles produced by air gouging processes are common pollutants in cleaning workshops, which could endanger workers' health. In this research, a two-way coupled Eulerian-Lagrangian method based on discrete phase modelling (DPM) was used to investigate the transport characteristics of high-temperature particles generated from air gouging processes. The particle group in the movement was divided into core zone and boundary zone, and the kinetic mechanism of particles in different zones was analysed. The results show particles in the boundary zone are more susceptible to the vortex entrainment effect than particles in the core zone, and some particles could be moved from the vortex diffusion zone to the vortex recirculation zone. The smaller the particle size, the better the followability to the hot airflow. The slower the temperature decay of particles, the more significant the thermophoresis effect, which could enhance the diffusion behaviour of the small particles. By analysing the average residence time of particles in the breathing zone, the influence of different factors on the average vertical diffusion height h p ¯ of particles is summarized, and a nonlinear regression prediction model of h p ¯ is established. The results can contribute to health risk assessment and industrial ventilation design. [ABSTRACT FROM AUTHOR]

Flow behavior of nonlinear materials over magnetized and contracting and extending inclined surfaces is described specifically by Jeffery–Hamel type flow, where the flow is caused by a convergent/divergent channel with the appearance of a source or sink. The role of the conversion of more than one species to more than every other species is significant in the flow conduct of such types of nonlinear materials. However, for the desired higher thermal conductivity, the Brownian motion and thermophoretic forces are incorporated in this particular work. Moreover, the impacts of first‐order chemical reaction and slips on the velocity, thermal, and concentration distributions, respectively presented to portray the importance of the entire study. The liquid motion on such surfaces is further addressed with the involvement of viscous dissipation and solar radiation. The newly mathematically formulated work is then approximated via one of the built‐in approaches based on collocation methods. The key findings are determined through graphical illustration. The physically interesting growing velocity of the liquid motion is noticed with variation in the slippery motion parameter during the convergent channel case. The opposite trend is noted for the divergent channel case. Furthermore, the Brownian motion‐related parameter escalated the temperature of the liquid, and the reverse status of the liquid concentration is determined with variation in the same parameter. The mass fraction is determined in a declining conduct with the ascending variation in first‐order chemical reaction factor. At the end of the work, a comparison with existing results is provided with excellent agreement. [ABSTRACT FROM AUTHOR]

A mathematical model is constructed to investigate the behavior of peristaltic flow of Jeffrey fluid in an inclined tapered asymmetric porous channel. The fluid viscosity is taken as space dependent variable quantity. Heat absorption, Soret and Dufour effects are also retained in the current scrutiny. These preferences have broad applications in engineering, biology and industry. We began our investigation by taking into account the two‐dimensional inclined asymmetric porous channel. In the context of mathematical modeling, the appropriate dimensional nonlinear equations for momentum, heat and mass transport are simplified into dimensionless equations by applying the essential estimation of long wavelength and low Reynolds number. The solution of the governing equations is executed numerically. A graphical depiction of many crucial physical characteristics on velocity, temperature, concentration, heat transfer rate, Nusselt number and Streamlines have been reported in ending section. Temperature profile exhibits an escalation with the augmentation of Brinkman number Br$Br$ and Dufour number Du$Du$. For the growing values of Prandtl number pr$pr$, an increment in temperature profile is observed whilst a reverse tendency is captured for concentration profile. It is noted that concentration profile falls down owing to the enhancement in Soret number Sr$Sr$ and Schmidt number Sc$Sc$. An oscillatory outlook is noticed for heat transfer rate and Nusselt number. The novelty of this proposed model in the research domain specifically depends on considerations of the combined study of the Variable viscosity, Darcy resistance, Viscous dissipation, Mixed convention, Heat absorption, Soret and Dufour effects in peristaltic flow of non‐ Newtonian Jeffrey fluid in an inclined Asymmetric tapered channel under the influence of convective boundary conditions. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids, which have a higher effective thermal conductivity than both regular fluids and nanofluid, are essential in industrial, biomedical, and engineering applications. Blood flow via an artery is a useful application for the investigation of hybrid nanofluids (Cu and Al2O3). Graphs have been used to discuss the effects of flow elements on velocity, temperature, and concentrations where values have been tabulated. A hybrid combination made up of copper and aluminum oxide with volume percentages in the range of 0.01–0.2. The Dufour effect was lessened, the volume proportion of copper was reduced, and the heat transmission rate was successfully increased. Maximum rates of heat, mass, and skin friction transmission would result from stronger mixed convection. This significant initial study will provide engineers and scientists the knowledge on effective management of fluid flow while optimizing the connected complex systems. Before being written and solved with the help of Maple software, the flow control equations were simplified. Figures present the main findings of the study, including the influence of several physical parameters. The effects of physical factors on the flow distributions are illustrated in tables and figures. Water is employed as the basic fluid, and a combination of copper and alumina nanoparticle is used as the study material to investigate the heat and mass phenomena brought by the Dufour and Soret effect. Surface thermal efficiency is influenced by the Soret factor, whereas surface mass transfer is constrained by the Dufour effect. [ABSTRACT FROM AUTHOR]

Inspired by the progressive relaxation characteristics of the Jeffrey model and its applied advantages in the rheological modeling of various dynamic fluids, the current study is focused to investigate the heat and mass transfer of magnetohydrodynamic (MHD) Jeffrey hybrid nanofluid flow over bi‐directional stretching sheet with convective boundary conditions. Additionally, the Cattaneo–Christov model of heat and mass flux is employed to take into consideration the time relaxation effects. The energy and concentration equation are taken into account to explore the effects of thermophoresis and Brownian motion. Homotopy analysis method (HAM) is employed for the solution of the current problem. Solution methodology is verified by comparing present results with those already published in open literature. The physical aspects of obtained graphical and numerical results are explained in detail to justify acquired trends. From the investigation, it is inferred that the magnetic and viscoelastic factors have a reducing influence on the flow profile along primary and secondary directions, while the stretching parameter has an increasing behavior on the flow profile in the secondary direction. Furthermore, the Brownian motion, magnetic parameter, and thermophoretic parameter have an escalating behavior on thermal distribution; however, the Brownian motion has a declining consequence on the concentration profile. The larger Biot number heightens the thermal and concentration distributions. [ABSTRACT FROM AUTHOR]

This paper signifies the consequence of the thermal diffusion (Soret) and diffusion-Thermo (Dufour) effect on MHD stagnation point flow and transportation of thermal energy near a stretching plate. However, the inclusion of thermal radiation, heat generation/absorption, and chemical reaction enriches the profiles significantly. By using similarity transformation, the set of leading equations is altered into a set of dimensionless ordinary differential equations. After that, the aim is to convert boundary layer equations into dimensionless ones so that the set of converting equations is computed by using bvp4c solver on MATLAB software. The governing nonlinear equations were resolved with Runge–Kutta fourth-order technique numerically. The significance of radiation, magnetic field, suction, Schmidt number, velocity ratio parameter, heat absorption coefficient, permeability, thermo-diffusion number, diffusion-thermo number on momentum gradient, energy gradient and concentration gradient distribution is analyzed. The parameters, diffusion-thermo number Du and thermo-diffusion number Sr have opposite behaviors on both temperature and concentration fields. Here, also, it is observed that the heat sink parameter has a noticeable influence on the fluid temperature distribution profile. [ABSTRACT FROM AUTHOR]

This work investigates the Casson ternary hybrid nanofluid flow on a dual-directional elongating surface with variable porosity. The flow is affected by chemical reactivity, exponential heat source and thermally radiative effects. To control the thermal feature of flow, the impacts of Brownian motion and thermophoresis are also incorporated in the flow model along with Cattaneo–Christov mass/heat flux phenomena. Appropriate variables have been employed to convert the leading equations to dimension-free form and then solved by using the bvp4c approach. It has been noticed as an outcome of this work that, with the upsurge in magnetic and variable porous factors, both the primary and secondary velocities have been diminished. Augmentation in thermal profiles is caused by the escalation in radiation, thermophoresis, Brownian motion factors and thermal Biot number while it has reduced with the upsurge in thermal relaxation factor. Concentration distribution has increased by the growth in thermophoresis, activation energy factors and concentration Biot number, whereas it has diminished with escalation in Brownian motion, chemical reactivity and mass relaxation factors. Moreover, concentration distribution also declined with a higher Schmidt number. To ensure the validation of the current model, its results have been compared with previously established datasets available in the literature. A closed agreement between our results and the dataset published previously has been noticed, which ensures the authenticity of the current work. [ABSTRACT FROM AUTHOR]

This work examines the numerical representation of boundary layer flow across a horizontal plate using the non-Darcian Maxwell model. The inspiration of mass transfer, heat generation, the Soret effect, the non-Darcy effect, Arrhenius activation energy and thermal radiation are all covered in this study. The relevant similarity transformations are applied in primary equations and a built-in bvp4c program is employed for solutions. The effectiveness of the numerical approach is demonstrated by a thorough agreement with results that have been published in the past. The results are shown in tables and graphical representations that highlight multiple parameters including the non-Darcy parameter, Deborah number, magnetic parameter, Soret parameter, chemical reactions, activation energy, etc. Figures show that fluid velocity is enhanced by Deborah number whereas it slips due to non-Darcy parameter and magnetic parameter. Eckert number, Radiation enhances the temperature profile and slips due to the Prandtl number. Activation energy enhances the Concentration field but it declines due to chemical reaction. [ABSTRACT FROM AUTHOR]

Migration of colloidal particles induced by temperature gradients is commonly referred to as thermodiffusion, thermal diffusion, or the (Ludwig-)Soret effect. The thermophoretic force experienced by a colloidal particle that drives thermodiffusion consists of two distinct contributions: a contribution resulting from internal degrees of freedom of single colloidal particles, and a contribution due to the interactions between the colloids. We present an irreversible thermodynamics based theory for the latter collective contribution to the thermophoretic force. The present theory leads to a novel "thermophoretic interaction force" (for uncharged colloids), which has not been identified in earlier approaches. In addition, an N -particle Smoluchowski equation including temperature gradients is proposed, which complies with the irreversible thermodynamics approach. A comparison with experiments on colloids with a temperature dependent attractive interaction potential over a large concentration and temperature range is presented. The comparison shows that the novel thermophoretic interaction force is essential to describe data on the Soret coefficient and the thermodiffusion coefficient. • An irreversible thermodynamics based theory is presented leading to a novel "thermophoretic interaction force" on colloidal particles that originates from their mutual interactions. • Explicit microscopic expressions are found for the Soret coefficient and the thermodiffusion coefficient in terms of the (equilibrium) pair-correlation function. • The novel thermophoretic interaction force is essential to be able to describe the experimental data. [ABSTRACT FROM AUTHOR]

The current work investigates the effects of oblique Lorentz force and Navier's slip boundary condition on unsteady hybrid nanoliquid flow with three different base liquids (H2O, CH3OH and H2O–EG) across a nonlinearly elongating surface set in a porous medium. This research considers the effects of viscous–Ohmic dissipation, nonlinearly variable thermal radiation, internal heat source, the Soret effect, first-order chemical reaction and thermal and solutal jump conditions at the boundary. Proper thermo-physical relationships for the hybrid nanoliquid have been established. Rosseland's estimate for an optically thick regime is used when calculating the heat flow owing to radiation. The dimensional governing equations are translated into nondimensional forms using appropriate similarity transformations. The velocity, energy and concentration fields are numerically solved using a shooting strategy based on the secant iteration and the Runge–Kutta–Fehlberg method. The physical implications of several essential parameters on the hybrid nanoliquid velocity, temperature and concentration are investigated using graphical and tabular representations of numerical data. Furthermore, the multiple (quadratic) regression analysis reveals that physical parameters strongly influence the local skin friction coefficient, Sherwood and Nusselt numbers. For continuously growing values of the unsteadiness parameter, the velocity, thermal and concentration scattering declined everywhere within the boundary layer region. [ABSTRACT FROM AUTHOR]

Purpose: Fluid flows through rotatory disks are encountered in industrial and practical engineering processes, such as computer storage devices, gas turbine rotators, rotating machinery, air cleaning machines, etc. The primary purpose of this research is to examine the combined aspects of variable electrical conductivity, thermal radiation, Soret and Dufour effects on a magnetohydrodynamic Maxwell single-walled carbon nanotubes–graphene oxide–multi-walled carbon nanotubes–copper (SWCNT–GO–MWCNT–Cu)/sodium alginate tetra-hybrid nanofluid flow through a stretchable rotatory disk. Design/methodology/approach: The modeled administrative equations of the present flow problem are converted to a non-dimensional system of ordinary differential equations by applying suitable similarity conversion and then solved numerically by implementing the bvp4c method. The impressions of noteworthy dimensionless parameters on velocity, temperature, concentration distributions, Nusselt number, skin friction and Sherwood number are reported via graphs and tables. Findings: The authors figured out that the developed values of the rotation parameter diminish the temperature but enhance both the radial and angular velocities. Further, the mass and heat transmission rates are better for tetra-hybrid nanofluids than for ternary and hybrid nanofluids. Originality/value: The present study emphasizes a special type of fluid called the tetra-hybrid nanofluid. The existing literature has not discussed the Maxwell tetra hybrid nanofluid flow through a stretchable rotatory disk with variable electrical conductivity. Besides, the novel aspects of magnetohydrodynamics, thermal radiation, Soret and Dufour effects are also incorporated into the present flow problem. [ABSTRACT FROM AUTHOR]

The goal of the current investigation is to ascertain the influence of Soret and Dufour on a magneto‐micropolar fluid past a permeable stretching surface with a nonuniform heat source/sink. Moreover, the investigation considers the influence of melting heat transfer, as well as the implications of velocity, thermal, and solutal slips. Numerical solutions to the basic governing equations are achieved using the Runge–Kutta–Fehlberg technique. The analysis of our results reveals several important findings. Enhancing the material parameter leads to an upsurge in the velocity profile, whereas the opposite trend exists for the boosting estimations of the magnetic parameter. Enhancing the Soret parameter leads to an improvement in the concentration profile while improving the Dufour factor results in an enhancement in the temperature distribution. These findings are critical for understanding the heat transfer over a stretching sheet, subject to different models and they encompass aspects such as temperature distribution, heat transfer rates, boundary layer characteristics, velocity profiles, and the potential for implementing heat transfer enhancement techniques. The findings of this current investigation are consistent with those that have been previously reported. Fluid dynamics, materials processing, cooling systems, and thermal systems are just a few of the real‐life domains that can benefit from understanding magneto‐micropolar fluid flow over a porous stretching surface with a nonuniform heat source–sink and incorporating Soret and Dufour effects. [ABSTRACT FROM AUTHOR]

The present study explores the nanofluid boundary layer flow over a stretching sheet with the combined influence of the double diffusive effects of thermophoresis and Brownian motion effects. For the purpose of transforming nonlinear partial differential equations into the linear united ordinary differential equation method, the similarity transformation technique is used. The Runge–Kutta–Fehlberg method was used to solve the equations of flow, along with sufficient boundary conditions. The effect on hydrodynamic, thermal and solutes boundary layers of a number of related parameters is investigated and the effects are graphically displayed. In conclusion, a strong agreement between the current numerical findings and the previous literature results is sought. [ABSTRACT FROM AUTHOR]

The complete description of energy and material transport within the Generalized energy-conserving dissipative particle dynamics with mass transfer (GenDPDE-M) methodology is presented. In particular, the dynamic coupling between mass and energy is incorporated into the GenDPDE-M, which was previously introduced with dynamically decoupled fluxes (J. Bonet Avalos et al., J. Chem. Theory Comput., 18 (12): 7639–7652, 2022). From a theoretical perspective, we have derived the appropriate Fluctuation-Dissipation theorems along with Onsager's reciprocal relations, suitable for mesoscale models featuring this coupling. Equilibrium and non-equilibrium simulations are performed to demonstrate the internal thermodynamic consistency of the method, as well as the ability to capture the Ludwig–Soret effect, and tune its strength through the mesoscopic parameters. In view of the completeness of the presented approach, GenDPDE-M is the most general Lagrangian method to deal with complex fluids and systems at the mesoscale, where thermal agitation is relevant. [ABSTRACT FROM AUTHOR]

Thermophoresis refers to the directional movement of particles driven by temperature gradients, which is ubiquitous in nature. This phenomenon can be conveniently used to manipulate molecules and objects such as biomolecules, colloids, metal nanoparticles, and cells. Because of these advantages, thermophoresis is widely used in biosensing. In vitro diagnosis, as an important field of biosensing, is highly compatible with thermophoresis. Compared with traditional in vitro diagnostic techniques, thermophoretic diagnosis is a homogeneous system that boasts high efficiency and rapid detection as well as a wide detection range; thus, thermophoresis has a myriad of applications. The emergence of microscale and multifield coupling thermophoresis technologies yield widespread applications of thermophoresis in the field of in vitro diagnostics. This study presents the history of thermophoresis and reviews various cases of biosensors utilizing thermophoresis. Those biosensors are widely used in in vitro diagnostics, biomarker discovery, and other fields. Furthermore, it assesses the advantages of thermophoresis, and finally discusses its current challenges and future development. [ABSTRACT FROM AUTHOR]

The Soret and Dufour effects play a crucial role in various fields such as geosciences, groundwater pollutant migration, chemical reactor operations, binary alloy solidification, and isotope separation. This study focuses on examining the impact of mixed convective flow on hybrid nanofluid through an exponentially stretching sheet with Soret and Dufour effects. The flow is affected by factors like variable viscosity, radiation, viscous dissipation, and activation energy. Instead of the no‐slip condition at the boundary, velocity slip, thermal slip, and concentration slip are considered. The physical problem is modeled using boundary layer theory, and flow patterns are expressed using partial differential equations (PDEs). These governing fluid flow equations are transformed into non‐linearly coupled ordinary differential equations (ODEs) using exponential similarity transformations. These simplified ODEs are resolved using the MATLAB bvp4c package. The effects of physical parameters on velocity, temperature, and concentration are illustrated through figures. Additionally, the drag force coefficient and heat and mass transfer rates are calculated for various parameters and presented graphically and in tabular form. It is observed that compared to nanofluids, the drag force coefficient of hybrid nanofluids increases by up to 21.05% with various solute buoyancy parameters (δ). Also, the mass transfer rate of hybrid nanofluids can be increased by.96% by the chemical reaction rate (σm). A comparison of this work with previously published research has been reported. [ABSTRACT FROM AUTHOR]

Study on the soot behaviors in hemicellulose pyrolysis is essential for the enhancement of gasification performance and solution of PM-related problems. In this work, a one-dimensional model is adopted to calculate the heating up and pyrolysis of xylan. The primary devolatilization is calculated by bio-CPD model, while the soot formation is simulated with one-step reaction with tar as the precursor. The effect of particle distance, soot radiation, and thermophoresis force on soot behaviors are discussed in detail. A smaller particle distance leads to less soot during xylan pyrolysis, which is contrary to the trend in biomass gasification. For pyrolysis, soot formation rate dominates, which decreases when particle distance decreases. For gasification, soot consumption rate dominates, which decreases when particle distance decreases. Soot radiation during xylan pyrolysis tends to heat up the soot itself and tar since their temperature is lower than ambient temperature, which is different from combustion and gasification conditions. Thus, when soot radiation is included in the model, temperature is higher and all soot-relevant reactions are faster. At the late stage of xylan pyrolysis, diffusion makes soot move towards both xylan particle and outer boundary, while thermophoresis offers an additional driven force for soot to get close to xylan particle. When thermophoresis is included in the model, soot mass fraction decreases more slowly at the late stage. [ABSTRACT FROM AUTHOR]

Interatomic forces significantly influence the flow behavior and dispersion stability of the suspensions in new thermal applications. Using a molecular dynamics technique, the current work focuses on the interatomic forces are estimated. The present analysis accounts for significant contributing factors such as drag force, Brownian force, thermophoresis force, and DLVO potential force of attraction or repulsion by using several nanoparticle dispersions, including SiO2, CNT, and GO in distilled water as the base fluid. Among all the particles considered for the study, Carbon Nanotube (CNT) showed the highest time of stability in the base fluid. That means CNT will take more time to settle down than GO (graphene oxide) and SiO2 due to its lowest density. The drag forces are high for GO (graphene oxide) mixed fluid due to its inherent properties. Another important finding is, below 0.05% volume fraction, the drag forces are insignificant for all the considered samples of analysis. The Brownian force is analyzed for various time intervals, which reports that for the initial periods of collision (Δt = 0.01) the molecular agitation is greater. However, increasing the Δt suppresses these forces. From the results, it is clear that the magnitude of Brownian force is dominant with CNT nanofluid, whereas it is the least intensity for SiO2 nano fluid. The magnitude of thermophoresis forces is less than that of drag forces, and it is observed to reach its maximum intensity at T/x = 100, indicating that temperature gradient has a dominant influence on nanoparticle movements. DLVO force of nano particle mixed water is also estimated with respect to volume fraction. Increasing the volume fraction increases the intensity of these forces. These forces are maximum for GO nano fluid. [ABSTRACT FROM AUTHOR]

The Rotary Hearth Furnace (RHF) process is an effective method for treating zinc-containing dust to recover valuable metals, but the significant deposition of flue gas during processing limits production efficiency. This study provides detailed insights into the mechanism of flue gas deposition in the treatment of zinc-containing dust in RHF through X-ray fluorescence spectrometer, X-ray diffraction, scanning electron microscopy, theoretical thermodynamic calculation and flue gas deposition experiments under high-temperature roasting. The results show that the deposits consist of ZnO, NaCl, KCl, K2SO4, Na2SO4, and ZnCl2. During the flue gas deposition process, ZnCl2 firstly precipitates and aggregates other deposited particles as a binding phase to form agglomerates. Under the driven by the thermophoresis of the flue gas, the agglomerates contact the heated surface, creating the initial deposition layer. The rough surface of this layer accelerates the deposition of chloride compounds from the flue gas. As the flue gas flows, the deposition layer continues to grow, leading to an increase in layer thickness and the eventual formation of periodic dense deposits. [ABSTRACT FROM AUTHOR]

The need to examine the thermal transport of hybrid nanofluids has arisen from the need for improved heat transfer to control the rising heat density of small‐scale and many other technical procedures. Hybrid nanofluids are made up of two different kinds of nanoparticles suspended in the primary fluid. This improves the ability of regular fluids to transport heat and makes them better heat exponents than nanofluids. In this study, we evaluate the cross‐flow and heat transport characteristics of Williamson hybrid nanofluid across an extendable surface. The impacts of thermal radiation, non‐uniform heat sources, and magnetic effects are provoked in this study. The set of partial different equations is obtained as a result of the theoretical formulation. The similarity variables are hired to get the ordinary differential equations. The bvp4c solver is availed to compute the numerical dual solutions for different physical parameters. The results indicate that the friction factor is enhanced due to the presence of magnetic, suction, and Williamson parameters. Whereas, the heat transfer rate decreases due to Williamson and magnetic parameters, whilst the opposite impact is seen due to suction. Moreover, the Williamson parameter reduces the Sherwood number, whereas the suction uplifts the Sherwood number. [ABSTRACT FROM AUTHOR]

This innovative study investigates the flow of ternary hybrid nanofluid containing gyrotactic microorganisms in microchannel. The magnetic field, thermophoresis, and Brownian motion effects are analyzed. The transformation of the PDEs system into ODEs is carried out by using the group transformation method. The innovative findings examine the Newtonian and non-Newtonian models derived from the system of ODEs. Several graphs illustrate how different parameters affect the velocity profile, temperature, concentration, and microorganisms. The power-law index value increases the fluid flow velocity by about 9% at n = 3, 36% at n = 4 relative to the case of n = 2.5 at the center of the boundary layer. Moreover, the ternary hybrid nanofluid exhibits a greater temperature compared to the nanofluid. The current results are compared to the researchers' findings to confirm the validity of the obtained results. When the Prandtl number is between 6 and 10, the Nusselt number reaches 45.49%. [ABSTRACT FROM AUTHOR]

The current research simulates the mass and heat energy transmission model on MHD fluid flow under concentration and temperature deviations on a two-dimensional viscous fluid along an upright facet. Following boundary layer estimations, mathematical simulations for the movement of fluids, the conveyance of heat and mass exposed to radiation, thermophoresis, and Dufour consequences are generated as a set of partial differential equations. The surface's resilient suction was assessed. The built-in solver bvp4c in MATLAB is used for numerically debugging the aforementioned models. Through the inclusion of visualizations and tables, the detrimental effects of influencing variables are examined on the velocity, temperature as well as concentration gradients in conjunction with on the skin friction, Nusselt number, and Sherwood number. Excellent coherence may be shown when comparing between the most present findings and those that have previously been made available in the literature in specific limited circumstances. The Dufour effect, radiation, thermophoresis, and the Grashof number are all factors that influence fluid motion and heat transmission at the interface layer of dirt. Moreover, developments in the Shearing stress, Nusselt number, and Sherwood number coefficient are calculated. The findings are crucial for optimizing a variety of fluid-based technologies and systems, allowing developments in a number of industries including energy-effectiveness, electronics cooling, pursued medicine administration, and many more.

Abstract Asphaltene deposition may pose serious challenges to flow assurance of crude oil in well columns. Different aggregation kinetics would partly be responsible for asphaltene particle growth ending in deposition on the surface of well columns. This work primarily investigates the thermophoretic deposition velocity caused by temperature gradients inside well columns for various asphaltene aggregation kinetics, including crossover behaviour, sedimentation, reaction-limited aggregation (RLA), and diffusion-limited aggregation (DLA). To do so, the experimental observations of size distribution for a live crude oil was performed at 80 °C and pressure range of 4500–5500 psia. Moreover, various patterns of different size distributions were gathered from the literature for the sake of comparison. Next, a well column in southern Iran was selected to study the kinetic behaviour of thermophoretic velocity of deposition, with a difference between geothermal and static temperatures of around 5 to 50 °C. The non-isothermal deposition velocity was shown to decrease from the top to the bottom of the well column, according to the findings of the study. The results also revealed that the thermophoretic velocity decreases as particle size increases and vice versa. This was confirmed by examining a comparably large range of asphaltene particle sizes, ranging from approximately 100 nm to roughly 9 µm. Practical implications of these findings were also discussed which would provide guidance for mitigation of asphaltene deposition in well columns.

[Display omitted] Artificial colloidal motors capable of converting various external energy into mechanical motion, have emerged as attractive photosensitizer (PS) nanocarriers with good deliverability for photodynamic therapy. However, photoactivated 3O 2 -to-1O 2 transformation as the most crucial energy transfer of the photodynamic process itself is still challenging to convert into autonomous transport. Herein, we report on PS-loaded thiophane-containing semiconducting conjugated polymer (SCP)-based polymer colloidal motors with asymmetric geometry for photodynamic-regulated propulsion in the liquid. The asymmetrical presence of the SCP phases within the colloidal motors would lead to significant differences in the 3O 2 -to-1O 2 transformation and 1O 2 release manners between asymmetrical polymer phases, spontaneously creating asymmetrical osmotic pressure gradients across the nanoparticles for powering the self-propelled motion under photodynamic regulation. This photoactivated energy-converting behavior can be also combined with the photothermal conversion of the SCP phases to create two energy gradients exerting diffusiophoretic/thermophoretic force on the colloidal motors for achieving multimode synergistic propulsion. This unique motile feature endows the light-driven PS nanocarriers with good permeability against various physiological barriers in the tumor microenvironment for enhancing antitumor efficacy, showing great potential in phototherapy. [ABSTRACT FROM AUTHOR]