Binary Reactions Research Articles

Stability analysis of radiative-magnetive Ag −MoS 2/water hybrid nanofluid flow due to a permeable exponential surface with variable thermal conductivity, mass diffusivity and binary chemical reaction: an entropy generation

ABSTRACT This investigation concentrated on the /water hybrid nanofluid to solve the problem of heat-mass transmission across a permeable stretching/contracting sheet with the impacts of radiant heat and inclined magnetic force field. Here, we additionally take into account hybrid nanofluids with variable thermal conductivity, variable mass diffusivity, Joule dissipation, binary chemical reactions with velocity, and thermal and solutal slip conditions. Before being numerically solved by the MATLAB function bvp4c, the controlling PDE is converted into nonlinear coupled ordinary differential equations by appropriate similarity transformation. The findings also point to the presence of dual solutions in the stretching/contracting sheet region for a given value of the mass suction parameter, with stable upper branch solution and unstable lower branch solution. As a result of the velocity and temperature gradients, the entropy generation equation is constructed. The effects of the selected parameters are discussed and visually displayed for the velocity, temperature, concentration, skin friction coefficient, local Nusselt number, and Sherwood number. Due to some selected flow parameters, the pattern of entropy formation and assessment of the Bejan number are anticipated. Furthermore, it is discovered that when the volume percentage of nanoparticles increases, the Sherwood number decreases, and the skin friction coefficient increases with the rate of heat transmission. The Bejan number and entropy generation rate both increase with the volume proportion of nanoparticles and the radiant heat parameter, according to the visual simulations created using the present model.

Utilization of erythrosine B in spectrofluorimetric quenching analysis of amlodipine and perindopril in pharmaceutical and biological matrices.

A spectrofluorimetric approach that is sensitive, simple, validated, and cost-effective has been proposed for the estimation of amlodipine (AML) and perindopril (PER) in their bulk powders, pharmaceutical formulations, and spiked human plasma. The recommended approach utilized the quantitative quenching effect of the two cited drugs on the fluorescence intensity of erythrosine B, as a result of complex binary reactions among each drug with erythrosine B at pH3.5 (Teorell and Stenhagen buffer). The quenching of erythrosine B fluorescence was recorded at 554 nm after excitation at 527 nm. The calibration curve was detected in the range 0.25-3.0μg ml-1 , with a correlation coefficient of 0.9996 for AML, and 0.1-1.5μg ml-1 , with a correlation coefficient of 0.9996 for PER. The established spectrofluorimetric approach was validated for the estimation of the cited drugs with high sensitivity regarding International Council on Harmonization guidelines. Therefore, the established approach could be utilized for quality control of the cited drugs in their pharmaceutical formulations.

A regression model for plasma reaction kinetics

Machine learning (ML) is used to provide reactions rates appropriate for models of low temperature plasmas with a focus on A + B C + D binary chemical reactions. The regression model is trained on data extracted from the QBD, KIDA, NFRI and UfDA databases. The regression model used a variety of data on the reactant and product species, some of which also had to be estimated using ML. The final model is a voting regressor comprising three distinct optimized regression models: a support vector regressor, random forest regressor and a gradient-boosted trees regressor model; this model is made freely available via a GitHub repository. As a sample use case, the ML results are used to augment the chemistry of a BCl3/H2 gas mixture.

Exploration of Radiative and Dissipative Heat on Williamson Nanofluid Flow in Conjunction with Convective Boundary Condition

Nanofluid has a wide range of uses in various fluid systems, because of its excellent growth in thermal conductivity. The current paper explores the transfer of heat and mass process in MHD nanofluid flow across a stretching sheet, considering the collective impacts of nonlinear thermal radiation, Joule heating, and binary chemical reactions with convective boundary conditions for Williamson nanofluid. The necessary transformations are carried out to alter the controlling PDE’s into a collection of linked ODE’s. The shooting approach, in conjunction with the fourth-order Runge–Kutta method, is employed to get solutions to highly nonlinear ODE’s. The impact of varied main factors on velocity, temperature, concentration, for Weissenberg number, Biot number along with other parameters are depicted graphically, whilst the change in the rate of heat and mass transfer is investigated via numerical data in tabular form. The acquired numerical data show that expanding the Eckert number diminishes the rate of mass transfer whereas expanding the thermal radiation parameter, expandsthe rate of heatand rate of mass transfer.

Comparative analysis of the hydrothermal features of TiO2 water and ethylene glycol-based nanofluid transportation over a radially stretchable disk

This study focuses on the comprehensive analysis of the thermal characterization of an electrically conducting nanofluid flow containing TiO2 nanoparticles dissolved in two different common liquids (H2O and C2H6O2) and contained within a continuously extending disk. The heat and concentration formulation are modified by incorporating the standard interpretations of the Joule heating, energy source, dissipation, and modified activation energy with binary chemical reactions. The Darcy–Forchheimer addition is used to highlight the significance of porous media. The Brownian dispersion’s effects are clearly discernible in the current investigation. Furthermore, as a novelty, special thermophysical models of viscosity and thermal conductivity are included. The obtained differential formulations are tackled through the analytical procedure HAM. The veracity of the finding is verified through a numerical scheme (ND-solve technique). Using several graphs and charts, the perception trends of model factors are evaluated. The influence of and are estimated based on flow characteristics. The curve pattern for both nanofluids is declined by the increasing magnitude of and while thermal profile. The drag force and heat transmission rate are shown to optimize with as well as in the pictorial simulations produced from the existing model. The can also be strengthened by the presence of a high degree The outcomes are validated by previous studies and a good degree of consistency is revealed.

Quadratic convection in a power-law fluid with activation energy and suction/injection effects

Current research demonstrates the effects of activation energy and quadratic convection on the non-Newtonian power-law fluid flow through an inclined permeable plate. In addition, the fluid’s heat transfer is carefully investigated while taking convective boundary conditions and thermal radiation into account. Also, mass transfer between the flow and the inclined plate was investigated for binary chemical reactions. By appropriate transformations, governing fluid flow equations are changed into the dimensionless form. Numerical solution of this system of equations is obtained by both the local non-similarity method and the successive linearisation method. The effect of emerging parameters on the flow and physical quantities are examined with Biot number ( B i ), activation energy coefficient ( E ), the chemical reaction parameter ( M ), quadratic convection parameters ( α 1 , α 2 ), inclination angle ( Ω ), the suction/injection parameter ( f w ) and the radiation parameter ( R d ). Further, the rate of mass and heat transfer are compared for all the instances of linear and quadratic convective flows. Power-law fluids concentration is increased with activation energy, while it diminishes with chemical reaction. The thickness of thermal boundary layer is considerably enhanced by both Biot number and radiation parameters. The thermal and solutal rates are increasing functions of quadratic convection parameters.

Non-linear radiative heat flux of Williamson nanofluid with gyrotactic microorganisms, activation energy and bioconvection

Gyrotactic microorganisms and nanoparticles with bioconvection play an important mantle in heat exchanger, biosensors, cooling devices, biotechnology, heating, pharmaceutical, drying food and many more. The main objective and novelty of this study is to compute the numerical solutions for the transient bioconvection flow of non-Newtonian Williamson nanofluid over a permeable contracting/expanding cylinder under the effects of Arrhenius activation energy and gyrotactic microorganisms. Additionally, binary chemical reactions and nonlinear radiation aspects are considered. Furthermore, Buongiorno nanofluid model and revised nanofluid model are utilized to investigate heat and mass transportation. Numerical solutions of highly nonlinear ordinary differential system are developed through RK45 scheme. It is interesting to investigate that motile number is an enhancing function of bioconvection Lewis number but reverse trend is noticed for higher estimation of Peclet number and microorganisms difference parameter in both cases of stretching and shrinking cylinder.

Degradation of sulphapyridine by Fe-Mn binary oxide-mediated radical reactions

Degradation of sulphapyridine by Fe-Mn binary oxide-mediated radical reactions

A Quantum Chemical Investigation into the Molecular Mechanism of the Atmospheric Reactions of Chemi-Ions with Nitrogen and Nitrogen Oxides.

Nitrogen oxides and chemi-ions are atmospheric pollutants with considerable aeronomic interest. These toxicants can react with each other, producing various ionic species and highly reactive by-products that play a crucial role in aerosol clustering and mediate several important atmospheric reactions. Understanding the chemical reactivity of these pollutants can provide essential information for controlling their excess emission into the atmosphere. Computational modeling and electronic structure studies help in predicting the structure, reactivity, and thermodynamics of transient atmospheric chemical species and can guide experimental research by providing vital mechanistic insights and data. In the present study, a computational investigation into the mechanisms of the binary associative reactions between negative ions: O2− and O3− with NO, NO2, and N2 was conducted using the Coupled-Cluster Singles and Doubles (CCSD) theory. Five model reactions between N2/NOx with On− (n = 2, 3) were considered in this work. Our calculations revealed that reactions (2) and (5) are two sequential processes involving intermediates, and all others occur in a concerted manner by direct transitions from the reactants to the products, with no isolable intermediates proceeding via single non-planar transition states. Our study revealed that the higher activation barrier required for the formation of NO3− (2) as compared to NO2− (1) could be the reason for the excess formation of NO2− ions over NO3− ions in the atmosphere. Further, all the investigated reactions except (5) are found to be feasible at room temperature. The energy required to break N-N bonds in the N2 molecule justifies the high barrier for (5). The results obtained from the study are in close agreement with the available experimental data. Moreover, the data from the study can be utilized for the evaluation of experiments and model predictions pertaining to NOx oxidation and molecular modeling of the gas-phase chemistry of pollutants/nucleation precursors formed in the Earth’s atmosphere and aircraft engines.

Design and Construction of an ALD Reactor by Growth of Al2O3 Nanostructure Films

Objective: This project focuses on designing, building and commissioning work the atomic layer deposition (ALD) reactor for Al2O3 ultrathin film, which it will be contain specific components and a system's own control unit. Methodology: The ALD reactor was designed under a system to minimize components, flow lines and connections; to reduce manufacturing costs, volume of precursors, among others. Currently, ALD reactors are expensive to sell, maintain and replace parts. The design and manufacture of the ALD reactor manufactured at the University of Sonora (UNISON) is based on the state art with sequential binary reactions of the precursors, for the proposal for the manufacture of solar cells. Contribution: It was possible to build and commission the ALD reactor for the deposition of ultra-thin films, with the characteristics of being reproducible and scalable, which makes it attractive for commercialization. The homemade ALD reactor at UNISON is considered a very interesting equipment for the semiconductor research area, since it is possible to combine different types of materials in the form of films such as oxides and nitrides in the order of Angstroms (Ǻ).

Impact of Joule heating and multiple slips on a Maxwell nanofluid flow past a slendering surface

This manuscript presents a study of three-dimensional magnetohydrodynamic Maxwell nanofluid flow across a slendering stretched surface with Joule heating. The impact of binary chemical reactions, heat generation, thermal radiation, and thermophoretic effect is also taken into consideration. The multiple slip boundary conditions are utilized at the boundary of the surface. The appropriate similarity variable is used to transfer the flow modeled equations into ODEs, which are numerically solved by the utilization of the MATLAB bvp4c algorithm. The involved parameter’s impact on the concentration, velocity, and temperature distribution are scrutinized with graphs. The transport rates (mass, heat) are also investigated using the same variables, with the results reported in tabulated form. It is seen that the fluid relaxation, magnetic, and wall thickness characteristics diminish the velocities of fluid. Further, the velocity, concentration, and temperature slip parameters reduce the velocities of fluid, temperature, and concentration distribution. The results are compared to existing studies and shown to be in dependable agreement.

Uranium (VI) sorption on illite under varying carbonate concentrations: Batch experiments, modeling, and cryogenic time-resolved laser fluorescence spectroscopy study

Dissolved inorganic carbon (DIC) present in groundwaters can affect both the aqueous and surface species of hexavalent uranium (U(VI)) owing to its strong complexation ability with U(VI). However, the effect of DIC on U(VI) sorption on illite, which is a critical component of argillaceous rocks, is still unclear. In this study, we investigated the sorption of U(VI) on conditioned illite du Puy with varying DIC concentrations (up to 250 mM DIC) as a function of pH through batch sorption experiments, surface complexation modeling, and cryogenic time-resolved laser fluorescence spectroscopy (TRLFS). The distribution coefficients of U(VI) decreased with an increase in the DIC concentration. At relatively high DIC concentrations with respect to experimentally investigated range (≥100 mM DIC), no U(VI) sorption was observed. The U(VI) sorption on illite was modeled using the two-site protolysis non-electrostatic surface complexation and cation exchange model. Two ternary surface complexation reactions with carbonate were needed to depict the experimental sorption data in addition to binary and ternary hydroxo surface complexation reactions used to describe the U(VI) sorption to illite without carbonate. Cryogenic TRLFS data revealed that U(VI) did sorb to illite at high DIC concentrations (up to 10 mM DIC). The spectra were unchanged with varying DIC concentrations (2.0, 5.0, and 10 mM DIC) at pH ∼8.5, indicating that the surface speciation of U(VI) remained the same. The decay curves were biexponential, which further indicates that at least two surface species were responsible for the sorption. These results could improve the performance assessment of a deep geological disposal system in a sedimentary host rock.

Extended Migdal-Watson formula to evaluate background strength in binary breakup reactions

A new formula to evaluate the nonresonant background for binary breakup is proposed by extending the Migdal-Watson (MW) formula, which was originally developed for $s$-wave breakup in charge neutral systems. The strength of the direct breakup, which is assumed by a one step transition from the initial bound state, is simulated by the complex scaling method (CSM) in binary cluster systems. The extended MW formula is applied to the direct breakup of $^{20}\mathrm{Ne}\phantom{\rule{4pt}{0ex}}\ensuremath{\rightarrow}\phantom{\rule{4pt}{0ex}}\ensuremath{\alpha}+^{16}\mathrm{O}$, and we have found that the formula nicely reproduces the strength of the direct breakup evaluated by CSM. We have demonstrated that new parameters introduced in the extended MW formula have a close connection to the spatial size of the initial wave packet, which is given by the product of the initial wave function and the external field. The application of the new formula to the direct breakup of $^{12}\mathrm{Be}$ into $\ensuremath{\alpha}+^{8}\mathrm{He}$ is also discussed.

Non-linear radiative bioconvection flow of cross nano-material with gyrotatic microorganisms and activation energy

Bioconvection with gyrotactic microorganisms has a significant role in biotechnology and biosensors. This paper communicates a theoretical numerical investigation regarding the transient bioconvection flow of chemically reactive cross nanofluid over a permeable cylinder under the impact of nonlinear radiation and binary chemical reactions. Additionally, Arrhenius activation energy influences are taken into account. Further, revise model of nanoparticles is considered in present investigation. Boundary layer theory is invoked to develop the basic PDEs of microorganisms field, nanoparticles concentration, energy, momentum and mass for bioconvection flow of cross nanofluid in cylindrical coordinate system and then altered into nonlinear ODEs by utilizing the transforming variables. Numerical solutions of obtained highly nonlinear ODEs system are achieved through shooting Fehlberg approach for both the cases of stretching cylinder aw well as shrinking cylinder. Numerical computations for surface drag force, mass transfer rate, density number of microorganisms and heat transfer rate are executed. It is interesting to found that the density number of microorganisms is depreciated for higher estimation of Peclet number, microorganisms difference parameter and bioconvection Rayleigh number in both cases of stretching cylinder as well as shrinking cylinder. Furthermore, nanoparticles concentration is accelerated for the augmented values of activation energy parameter in shrinking as well as stretching cylinder. For the authenticity of considered study, we have also made a comparative analysis with existing study and noticed to be in excellent agreement.

Numerical study of bio-convection flow of magneto-cross nanofluid containing gyrotactic microorganisms with activation energy

In this study, a mathematical model is developed to scrutinize the transient magnetic flow of Cross nanoliquid past a stretching sheet with thermal radiation effects. Binary chemical reactions and heat source/sink effects along with convective boundary condition are also taken into the consideration. Appropriate similarity transformations are utilized to transform partial differential equations (PDE’s) into ordinary ones and then numerically tackled by shooting method. The impacts of different emerging parameters on the thermal, concentration, velocity, and micro-rotation profiles are incorporated and discussed in detail by means of graphs. Results reveal that, the escalation in magnetic parameter and Rayleigh number slowdowns the velocity and momentum of the fluid. The increase in Biot number, radiation and heat sink/source parameters upsurges the thermal boundary but, converse trend is seen for escalating Prandtl number. The density number of motile microorganisms acts as a growing function of bioconvection Lewis number and declining function of bioconvection Peclet number.

Mechanical aspects of Maxwell nanofluid in dynamic system with irreversible analysis

AbstractThe study concerns with the mechanical characteristics of rotating system of two double disks. Hall current effect, entropy generation, Arrhenius activation energy and binary chemical reactions are investigated in heat and mass transfer bioconvection flow of Maxwell nanofluid. Brownian motion and thermophoresis with thermal radiation and buoyancy effects are encountered in the governing equations. The mechanical system has been investigated by the governing equations and boundary conditions which are simplified by the use of suitable similarity transformations. Optimal homotopy analysis method is implemented to obtain the series solution of non‐linear ordinary differential equations. Physical behaviors of heat and mass transfer flow with entropy generation are investigated through the effects of embedded parameters.

Accessing tens-to-hundreds femtoseconds nuclear state lifetimes with low-energy binary heavy-ion reactions

A novel Monte Carlo technique has been developed to determine lifetimes of excited states in the tens-to-hundreds femtoseconds range in products of low-energy heavy-ion binary reactions, with complex velocity distributions. The method is based on a detailed study of Doppler-broadened gamma -ray lineshapes. Its relevance is demonstrated in connection with the ^{18}text {O}(7.0, text {MeV/u})+,^{181}text {Ta} experiment, performed at GANIL with the AGATA+VAMOS+PARIS setup, to study neutron-rich O, C, N, ... nuclei. Excited states in ^{17}text {O} and ^{19}text {O}, with known lifetimes, are used to validate the method over the sim 20{-}400,text {fs} lifetime-sensitivity range. Emphasis is given to the unprecedented position resolution provided by gamma -tracking arrays, which turns out to be essential for reaching the required accuracy in Doppler-shift correction. The technique is anticipated to be an important tool for lifetime investigations in exotic neutron-rich nuclei, produced with intense ISOL-type beams.

Phase evolution during annealing of low-temperature co-evaporated precursors for CZTSe solar cell absorbers

Systematic investigations into the phase evolution during reactive annealing of copper–zinc–tin–selenide (CZTSe) precursors for the fabrication of kesterite solar cell absorber layers have been paramount in understanding and suppressing the formation of secondary phases that deteriorate device performance. In this study, the phase evolution during annealing of low-temperature co-evaporated CZTSe precursors is investigated. A detailed analysis of films selenized at different temperatures is used to reveal the possible reaction pathway of CZTSe formation. Utilizing a combination of x-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive x-ray spectroscopy, it is shown that CZTSe formation starts by Cu out-diffusion to the surface and Cu–Se phase formation at a temperature of 350 °C. An intimate mixing of binaries and ternaries during low-temperature selenization is observed. On the contrary, only binaries are observed at high-temperature selenization. This suggests that the CZTSe formation pathway involves reaction schemes where (i) a competition between binary and ternary phases dominates at low-temperature and (ii) binary reactions dominate the process at high temperatures. However, the number of binary phases decreases with increasing selenization temperature until they become undetectable by XRD and Raman spectroscopy at a temperature of 540 °C (selenization time 10 min). Utilizing the presented selenization conditions, prototype solar cells with an efficiency of up to 7.5%, an open-circuit voltage of 407 mV, and a fill factor of 59%, could be demonstrated. The temperature-dependent current density–voltage characteristics indicate that the performance of the prototype devices is limited by bulk Schottky–Read–Hall recombination.

Microstructure evolution and sequence of phase transition reactions through the solidification of Mo-Si-B alloy; a phase-field study

The present study is focused on the phase evolution pattern and phase transition reactions between melt and arising solid phases during solidification of three different Mo-Si-B alloy compositions. To carry out this work, three alloy compositions from the Mo3Si, Mo5SiB2 and MoSS primary solidification regions, in the vicinity of ternary eutectic composition of Mo-Si-B system were selected. To investigate phase evolution and solidification reactions, a phase-field simulation is conducted with MicressTM applying the thermodynamic data generated with FactsageTM. The simulations confirmed the presence of binary and ternary eutectic reactions. It was observed that, depending on the initial melt composition, a primary phase emanates at the beginning of solidification which causes a composition fluctuation in the residual melt. Depending on the composition of the residual melt, thermodynamically feasible phases tend to perform a binary reaction until the rest of liquid undergoes the ternary MoSS-Mo5SiB2-Mo3Si eutectic reaction. However, exploring the solidification path of the considered compositions implied the uncertainties in considered thermodynamic parameters which requires the revision of thermodynamic database.

Development of Dynamic Model and Analytical Analysis for the Diffusion of Different Species in Non-Newtonian Nanofluid Swirling Flow

The analysis is carried out to analyze the flow through double stretchable rotating disks with the theory of radiative Cross nanofluid under the influence of variable thermal conductivity, the Hall current, Arrhenius activation energy, and binary chemical reactions. The Buongiorno nanofluid model is adopted for the governing equations of the problem which are transformed into ordinary differential equations through similarity transformations and then solved using the homotopy analysis method. The impact of dimensionless parameters on all profiles and physical quantities is presented and discussed. The radial velocity of the two disks increases with their corresponding ratio stretching rate parameter and decreases with the Hall parameter and the bioconvection Rayleigh number. The heat transfer at the lower disk enhances with the variable thermal conductivity parameter, while at the upper disk, opposite trend is observed. Mass transfer increases with the chemical reactions and temperature difference parameters at the lower disk and decreases with Arrhenius activation energy, whereas an opposite trend is observed at the upper disk. The local density number is enhanced for the larger values of Peclet and Lewis numbers. The comparison of the present work with the published literature authenticates the validation of the present work.