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Pinning particles at the equilibrium configuration of the liquid is expected not to affect the structure and any property that depends on the structure while slowing down the dynamics. This leads to a breakdown of the structure dynamics correlation. Here, we calculate two structural quantities: the pair excess entropy, S2, and the mean field caging potential, the inverse of which is our structural order parameter (SOP). We show that when the pinned particles are treated the same way as the mobile particles, both S2 and SOP of the mobile particles remain the same as those of the unpinned system, and the structure dynamics correlation decreases with an increase in pinning density, "c." However, when we treat the pinned particles as a different species, even if we consider that the structure does not change, the expression of S2 and SOP changes. The microscopic expressions show that the interaction between a pinned particle and a mobile particle affects S2 and SOP more than the interaction between two mobile particles. We show that a similar effect is also present in the calculation of the excess entropy and is the primary reason for the well-known vanishing of the configurational entropy at high temperatures. We further show that, contrary to the common belief, the pinning process does change the structure. When these two effects are considered, both S2 and SOP decrease with an increase in "c," and the correlation between the structural parameters and the dynamics continues even for higher values of "c." [ABSTRACT FROM AUTHOR]

Five high entropy carbide ceramics, (Hf0.2,Nb0.2,Ta0.2,Ti0.2,Zr0.2)C, (Cr0.2,Hf0.2,Ta0.2,Ti0.2,Zr0.2)C, (Hf0.2,Mo0.2,Ta0.2,Ti0.2,Zr0.2)C, (Hf0.2,Ta0.2,Ti0.2,W0.2,Zr0.2)C, and (Hf0.2,Mo0.2,Ti0.2,W0.2,Zr0.2)C, were synthesized by carbothermal reduction of oxides and direct current sintering. The five high entropy carbide ceramics were determined to be nominally phase-pure with relative densities of more than 98.9% and mean grain sizes of less than 5 μm. Average Vickers hardness values ranged from 19.2 ± 0.4 GPa for (Hf0.2,Nb0.2,Ta0.2,Ti0.2,Zr0.2)C at a load of 2 kgf to 43.5 ± 0.4 GPa for (Hf0.2,Mo0.2,Ti0.2,W0.2,Zr0.2)C at a load of 0.05 kgf. Hardness generally increased with increasing the valence electron concentration and strain as measured by the Williamson–Hall analysis. However, neither correlation was conclusive enough to be a clear indicator of hardness. Instead, it was determined that a combination of effects that includes the valence electron concentration, lattice strain, and grain size all contribute to the hardness of high entropy carbide ceramics. [ABSTRACT FROM AUTHOR]

The potential energy landscape (PEL) formalism is a tool within statistical mechanics that has been used in the past to calculate the equation of states (EOS) of classical rigid model liquids at low temperatures, where computer simulations may be challenging. In this work, we use classical molecular dynamics (MD) simulations and the PEL formalism to calculate the EOS of the flexible q-TIP4P/F water model. This model exhibits a liquid–liquid critical point (LLCP) in the supercooled regime, at (Pc = 150 MPa, Tc = 190 K, and ρc = 1.04 g/cm3) [using the reaction field technique]. The PEL-EOS of q-TIP4P/F water and the corresponding location of the LLCP are in very good agreement with the MD simulations. We show that the PEL of q-TIP4P/F water is Gaussian, which allows us to calculate the configurational entropy of the system, Sconf. The Sconf of q-TIP4P/F water is surprisingly similar to that reported previously for rigid water models, suggesting that intramolecular flexibility does not necessarily add roughness to the PEL. We also show that the Adam–Gibbs relation, which relates the diffusion coefficient D with Sconf, holds for the flexible q-TIP4P/F water model. Overall, our results indicate that the PEL formalism can be used to study molecular systems that include molecular flexibility, the common case in standard force fields. This is not trivial since the introduction of large bending/stretching mode frequencies is problematic in classical statistical mechanics. For example, as shown previously, we find that such high frequencies lead to unphysical (negative) entropy for q-TIP4P/F water when using classical statistical mechanics (yet, the PEL formalism can be applied successfully). [ABSTRACT FROM AUTHOR]

Entropy scaling is applied to the shear viscosity, self-diffusion coefficient, and thermal conductivity of simple monatomic fluids. An extensive molecular dynamics simulation series is performed to obtain these transport properties and the residual entropy of three potential model classes with variable repulsive exponents: n, 6 Mie (n = 9, 12, 15, and 18), Buckingham's exponential-six (α = 12, 14, 18, and 30), and Tang–Toennies (αT = 4.051, 4.275, and 4.600). A wide range of liquid and supercritical gas- and liquid-like states is covered with a total of 1120 state points. Comparisons to equations of state, literature data, and transport property correlations are made. Although the absolute transport property values within a given potential model class may strongly depend on the repulsive exponent, it is found that the repulsive steepness plays a negligible role when entropy scaling is applied. Hence, the plus-scaled transport properties of n, 6 Mie, exponential-six, and Tang–Toennies fluids lie basically on one master curve, which closely corresponds with entropy scaling correlations for the Lennard-Jones fluid. This trend is confirmed by literature data of n, 6 Mie, and exponential-six fluids. Furthermore, entropy scaling holds for state points where the Pearson correlation coefficient R is well below 0.9. The condition R > 0.9 for strongly correlating liquids is thus not necessary for the successful application of entropy scaling, pointing out that isomorph theory may be a part of a more general framework that is behind the success of entropy scaling. Density scaling reveals a strong influence of the repulsive exponent on this particular approach. [ABSTRACT FROM AUTHOR]

The nucleation of ice from aqueous solutions is a process essential to myriad environmental and industrial processes, but the physical factors affecting the capacity of different solutes to depress the homogeneous nucleation temperature of ice are yet poorly understood. In this work, we demonstrate that for many binary aqueous solutions of non-ionic solutes, this depression is dominated by the entropy of the liquid phase. Employing the classic Turnbull interpretation of the interfacial free energy γ ∼ T S l i q u i d − S s o l i d and estimating solution entropies with a Flory-style modification of the ideal entropy of mixing that accounts for solute size effects, we demonstrate that mixing entropy alone predicts experimental homogeneous nucleation temperatures across a wide variety of non-ionic solutions. We anticipate that this physical insight will not only enhance a fundamental understanding of homogeneous nucleation processes across fields but also open new avenues to the rational design of aqueous solutions for desired nucleation behaviors. [ABSTRACT FROM AUTHOR]

We present a theoretical model to study the effect of counterion size on the effective charge, size, and thermodynamic behavior of a single, isolated, and flexible polyelectrolyte (PE) chain. We analyze how altering counterion size modifies the energy and entropy contributions to the system, including the ion-pair free energy, excluded volume interactions, entropy of free and condensed ions, and dipolar attraction among monomer–counterion pairs, which result in competing effects challenging intuitive predictions. The PE self-energy is calculated using the Edwards–Muthukumar Hamiltonian, considering a Gaussian monomer distribution for the PE. The condensed ions are assumed to be confined within a cylindrical volume around the PE backbone. The dipolar and excluded volume interactions are described by the second and third virial coefficients. The assumption of freely rotating dipoles results in a first-order coil–globule transition of the PE chain. A more realistic, weaker dipolar attraction, parameterized in our theory, shifts it to a second-order continuous transition. We calculate the size scaling-exponent of the PE and find exponents according to the relative dominance of the electrostatic, excluded volume, or dipolar effects. We further identify the entropy- and energy-driven regimes of the effective charge and conformation of the PE, highlighting the interplay of free ion entropy and ion-pair energy with varying electrostatic strengths. The crossover strength, dependent on the counterion size, indicates that diminishing sizes favor counterion condensation at the expense of free ion entropy. The predictions of the model are consistent with trends in simulations and generalize the findings of the point-like counterion theories. [ABSTRACT FROM AUTHOR]

In polymers, the equilibrium state is achieved when the chains have access to the maximum number of conformational states, which allows them to explore a larger conformational space, leading to an increase in the entropy of the system. Preparation of thin polymer films using the spin-coating technique results in polymer chains being locked in a nonequilibrium state with lower entropy due to possible stretching of chains during the process. Allowing enough time for recovery results in the relaxation of the spin-coating-induced molecular recoiling stress. Annealing such a film generates entropy due to its inherent irreversibility. We employed the dewetting technique to determine the molecular recoiling stress relaxation time in poly-(tertbutyl styrene) thin films. Furthermore, we qualitatively differentiated the metastable states achieved by the polymer film using entropy generation in a relaxing polymer film as an effect of thermal entropy and associated it with the conformational entropy of polymer chains utilizing the molecular recoiling stress relaxation time. This enabled us to explain molecular recoiling stress relaxation using a rather simplistic approach involving segmental level molecular rearrangements in polymer chains by attaining transient metastable states through an entropically activated process driving toward equilibrium. [ABSTRACT FROM AUTHOR]

Henchman's approximate harmonic model of liquids is extended to predict the thermodynamic behavior along lines of constant excess entropy ("isomorphs") in the liquid and supercritical fluid regimes of the Lennard-Jones (LJ) potential phase diagram. Simple analytic expressions based on harmonic cell models of fluids are derived for the isomorph lines, one accurate version of which only requires as input parameters the average repulsive and attractive parts of the potential energy per particle at a single reference state point on the isomorph. The new harmonic cell routes for generating the isomorph lines are compared with those predicted by the literature molecular dynamics (MD) methods, the small step MD method giving typically the best agreement over a wide density and temperature range. Four routes to calculate the excess entropy in the MD simulations are compared, which includes employing Henchman's formulation, Widom's particle insertion method, thermodynamic integration, and parameterized LJ equations of state. The thermodynamic integration method proves to be the most computationally efficient. The excess entropy is resolved into contributions from the repulsive and attractive parts of the potential. The repulsive and attractive components of the potential energy, excess Helmholtz free energy, and excess entropy along a fluid isomorph are predicted to vary as ∼T−1/2 in the high temperature limit by an extension of classical inverse power potential perturbation theory statistical mechanics, trends that are confirmed by the MD simulations. [ABSTRACT FROM AUTHOR]

Due to their potential applications in energy production based on waste heat, direct solar radiation or other energy sources, semiconductor materials have for years attracted the attention of theoretical and experimental researchers. The focus has been on improving the performance of thermoelectric devices through several strategies and special interest has been placed on materials with spatially inhomogeneous transport properties. Inhomogeneity can be achieved in various ways, all of them leading, to a greater or lesser extent, to an improvement of the thermoelectric performance. In this paper, general linear heat and electric charge transport processes in inhomogeneous materials are addressed. The guiding idea followed here is that there exists a relationship between inhomogeneity (structuring), minimum entropy production and performance which may be fruitfully exploited for designing more efficient thermoelectric semiconductor devices. We first show that the stationary states of such materials are minimum global entropy production states. This constitutes an extension of the validity of Prigogine's minimum entropy principle. The heat and charge transport equations obtained within the framework of classical irreversible thermodynamics are solved to find the stationary profiles of temperature and self-consistent electric potential in a one-dimensional model of a silicon–germanium alloy subjected to an external temperature difference. This allows us to assess the effect of the spatial inhomogeneity on the thermoelectric performance. We find that, regardless of the value of the applied temperature difference, the system may efficiently operate in a regime of minimum entropy production and high efficiency. [ABSTRACT FROM AUTHOR]

For an electronic system, given a mean field method and a distribution of orbital occupation numbers that are close to the natural occupations of the correlated system, we provide formal evidence and computational support to the hypothesis that the entropy (or more precisely −σS, where σ is a parameter and S is the entropy) of such a distribution is a good approximation to the correlation energy. Underpinning the formal evidence are mild assumptions: the correlation energy is strictly a functional of the occupation numbers, and the occupation numbers derive from an invertible distribution. Computational support centers around employing different mean field methods and occupation number distributions (Fermi–Dirac, Gaussian, and linear), for which our claims are verified for a series of pilot calculations involving bond breaking and chemical reactions. This work establishes a formal footing for those methods employing entropy as a measure of electronic correlation energy (e.g., i-DMFT [Wang and Baerends, Phys. Rev. Lett. 128, 013001 (2022)] and TAO-DFT [J.-D. Chai, J. Chem. Phys. 136, 154104 (2012)]) and sets the stage for the widespread use of entropy functionals for approximating the (static) electronic correlation. [ABSTRACT FROM AUTHOR]

The Meyer–Neldel compensation law, observed in a wide variety of chemical reactions and other thermally activated processes, provides a proportionality between the entropic and the enthalpic components of an energy barrier. By analyzing 31 different polymer systems, we show that such an intriguing behavior is encountered also in the slow Arrhenius process, a recently discovered microscopic relaxation mode, responsible for several equilibration mechanisms both in the liquid and the glassy state. We interpret this behavior in terms of the multiexcitation entropy model, indicating that overcoming large energy barriers can require a high number of low-energy local excitations, providing a multiphonon relaxation process. [ABSTRACT FROM AUTHOR]

This work presents a method for calculating the difference in temperature jumps observed at the solid–water and water–solid interfaces when heat is flowing under steady state conditions from a hot to a cold solid separated by an intermediate water phase. The method is based on a hypothesis stating that the entropy flux is maximized where the heat flux is constrained, i.e., at the solid–water interfaces. By focusing on the entropy rather than the heat flux and by maximizing its value vs the magnitude of the temperature jump over the interfaces where the latter is constrained, simple analytical expressions for the jump differences independent of the actual heat flux are established only depending on the absolute temperature of the hot and cold solid. The results show that the temperature jump at the hotter interface, therefore, must be higher than the jump at the colder because of the differences in absolute temperature between the two interfaces, supported by many observations. The results, furthermore, show that the temperature jump asymmetry between the two interfaces should increase with decreasing absolute temperature of the system. The work, therefore, finally indicates that there are two quantities contributing to the magnitude of any temperature jump, the heat and entropy flux. More investigations about their relationship under different conditions are encouraged since the topic is not systematically acknowledged and, therefore, investigated in the literature. [ABSTRACT FROM AUTHOR]

Intramolecular electron transfer between two biphenyl groups linked by an androstane spacer and excitation of the pyridinium-N-phenolate betaine dye B30 to the first excited singlet state are studied by quantum/classical molecular-dynamics simulations at temperatures between 150 and 300 K in solvents with a range of polarities. Temperature dependences of the solvent reorganization energies, free energies, entropies, and the inhomogeneous broadening of B30's absorption band are examined. The variances of fluctuations of the energy gap between the reactant and product states do not have the direct proportionality to temperature that often is assumed to hold. An explanation for the observations is suggested. [ABSTRACT FROM AUTHOR]

We present the study of the structure–dynamics correlation for systems interacting via attractive Lennard-Jones (LJ) and its repulsive counterpart, the Weeks–Chandler–Andersen (WCA) potentials. The structural order parameter (SOP) is related to the microscopic mean-field caging potential. At a particle level, the SOP shows a distribution. Although the two systems have similar pair structures, their average SOP differs. However, this difference alone is insufficient to explain the well known slowing down of the dynamics in the LJ system at low temperatures. The slowing down can be explained in terms of a stronger coupling between the SOP and the dynamics. To understand the origin of this system specific coupling, we study the difference in the microscopic structure between the hard and soft particles. We find that for the LJ system, the structural differences of the hard and soft particles are more significant and have a much stronger temperature dependence compared to the WCA system. Thus, the study suggests that attractive interaction creates more structurally different communities. This broader difference in the structural communities is probably responsible for stronger coupling between the structure and dynamics. Thus, the system specific structure–dynamics correlation, which also leads to a faster slowing down in the dynamics, appears to have a structural origin. A comparison of the predictive power of our SOP with the local energy and two body excess entropy in determining the dynamics shows that in the LJ system, the enthalpy plays a dominant role and in the WCA system, the entropy plays a dominant role, and our SOP can capture both these contributions. [ABSTRACT FROM AUTHOR]

A unified theory is presented for finite-temperature many-body perturbation expansions of the anharmonic vibrational contributions to thermodynamic functions, i.e., the free energy, internal energy, and entropy. The theory is diagrammatically size-consistent at any order, as ensured by the linked-diagram theorem proved in this study, and, thus, applicable to molecular gases and solids on an equal footing. It is also a basis-set-free formalism, just like its underlying Bose–Einstein theory, capable of summing anharmonic effects over an infinite number of states analytically. It is formulated by the Rayleigh–Schrödinger-style recursions, generating sum-over-states formulas for the perturbation series, which unambiguously converges at the finite-temperature vibrational full-configuration-interaction limits. Two strategies are introduced to reduce these sum-over-states formulas into compact sum-over-modes analytical formulas. One is a purely algebraic method that factorizes each many-mode thermal average into a product of one-mode thermal averages, which are then evaluated by the thermal Born–Huang rules. Canonical forms of these rules are proposed, dramatically expediting the reduction process. The other is finite-temperature normal-ordered second quantization, which is fully developed in this study, including a proof of thermal Wick's theorem and the derivation of a normal-ordered vibrational Hamiltonian at finite temperature. The latter naturally defines a finite-temperature extension of size-extensive vibrational self-consistent field theory. These reduced formulas can be represented graphically as Feynman diagrams with resolvent lines, which include anomalous and renormalization diagrams. Two order-by-order and one general-order algorithms of computing these perturbation corrections are implemented and applied up to the eighth order. The results show no signs of Kohn–Luttinger-type nonconvergence. [ABSTRACT FROM AUTHOR]

The computation of entropy in liquids and liquid crystal (LC) phases is a big challenge in statistical physics. In this work, we extend the two-phase thermodynamic model (2PT) to shape anisotropic soft repulsive spherocylinders (SRSs) and report the absolute values of entropy for different LC phases for a range of aspect ratios L/D = 2 − 5. We calculate the density of states for different LC phases and decompose it into contributions arising from translational and rotational degrees of freedom. The translational and rotational modes are further partitioned into diffusive, gas-like, and non-diffusive, solid-like components using a fluidicity factor. In the dilute limit, the entropy values obtained from the 2PT method match exactly those of an ideal rigid rotor. We find that, for a given packing fraction, the magnitude of the total entropy is roughly equal regardless of the different LC phases associated with different aspect ratios. We also compute the excess entropy (for L/D = 5) and compare those with the values obtained using the standard integration approach of MD or Monte Carlo equation of state of SRS. The values obtained using both approaches match very well. The rotational and translational fluidicity factors are further used to determine the phase boundaries of different LC phases. [ABSTRACT FROM AUTHOR]

The complex interplay between competing phase stabilities of FCC, L12, BCC, and B2 phases in the Al0.25CoFeNi (7Al-31Co-31Fe-31Ni in at. %) high entropy alloy (HEA) leads to non-classical phase transformation pathways and resultant novel microstructures. Specifically, the competition between the homogenous precipitation of L12 and heterogenous precipitation of BCC/B2 can be studied at a temperature of 500 °C in the Al0.25CoFeNi alloy. Upon isothermally annealing the single FCC phase microstructure of this HEA at 500 °C up to 50 h, the transformation initiates with the formation of a transient ordered L12 phase with minor Ni–Al enrichment, which is far-from equilibrium, as revealed by atom probe tomography, and can be considered non-classical nucleation. The near equilibrium L12 phase eventually replaces the transient L12 during continued annealing at the same temperature. However, the resultant FCC + L12 microstructure is metastable because the true equilibrium for the Al0.25CoFeNi alloy at 500 °C is a mixture of L12 + B2 phases, as revealed by solution thermodynamics modeling. The higher nucleation barrier for the BCC-based ordered B2 phase coupled with the slower kinetics at 500 °C leads to the homogeneous precipitation of L12, while the B2 phase appears to sluggishly grow from grain boundaries acting as heterogeneous nucleation sites. [ABSTRACT FROM AUTHOR]

High-energy x-ray diffraction from molten and glassy BaB2O4 and BaB4O7 has been performed using aerodynamic levitation and laser heating over a wide range of temperatures. Remarkably, even in the presence of a heavy metal modifier dominating x-ray scattering, it was possible to extract accurate values for the tetrahedral, sp3, boron fraction, N4, which declines with increasing temperature, using bond valence-based mapping from the measured mean B–O bond lengths while accounting for vibrational thermal expansion. These are used within a boron-coordination-change model to extract enthalpies, ΔH, and entropies, ΔS, of isomerization between sp2 and sp3 boron. The results for BaB4O7, ΔH = 22(3) kJ mol−1 boron, ΔS = 19(2) J mol−1 boron K−1, agree quantitatively with those found previously for Na2B4O7. Analytical expressions for N4(J, T) and associated configurational heat capacity, C P conf (J, T), and entropy, Sconf(J, T), contributions are extended to cover a wide composition range 0 ≤ J = BaO/B2O3 ≤ 3 using a model for ΔH(J) and ΔS(J) derived empirically for lithium borates. Maxima in the C P conf (J, Tg) and fragility index contributions are thereby predicted for J ≲ 1, higher than the maximum observed and predicted in N4(J, Tg) at J ≃ 0.6. We discuss the utility of the boron-coordination-change isomerization model in the context of borate liquids containing other modifiers and the prospect of neutron diffraction to aid in empirical determinations of modifier-dependent effects, illustrated by new neutron diffraction data on Ba11B4O7 glass, its well-known α-polymorph, and lesser-known δ-phase. [ABSTRACT FROM AUTHOR]

Radial distribution functions (RDFs) are widely used in molecular simulation and beyond. Most approaches to computing RDFs require assembling a histogram over inter-particle separation distances. In turn, these histograms require a specific (and generally arbitrary) choice of discretization for bins. We demonstrate that this arbitrary choice for binning can lead to significant and spurious phenomena in several commonplace molecular-simulation analyses that make use of RDFs, such as identifying phase boundaries and generating excess entropy scaling relationships. We show that a straightforward approach (which we term Kernel-Averaging Method to Eliminate Length-Of-Bin Effects) mitigates these issues. This approach is based on systematic and mass-conserving mollification of RDFs using a Gaussian kernel. This technique has several advantages compared to existing methods, including being useful for cases where the original particle kinematic data have not been retained, and the only available data are the RDFs themselves. We also discuss the optimal implementation of this approach in the context of several application areas. [ABSTRACT FROM AUTHOR]

The influence of Al on the defect behaviors of AlxCoCrFeNi high-entropy alloys (HEAs) is studied by ab initio calculations. The lattice distortion, defect formation energies, and defect migration energies were calculated for different Al concentrations ranging from 0 to 6.25 at. %. First, the increase in the lattice distortion of AlxCoCrFeNi by the addition of Al is demonstrated, but the increment is smaller than that predicted by the atomic size difference of constituent elements. Second, although formation energies of Al vacancies and dumbbells containing Al are higher, the addition of Al decreases the average formation energies of vacancies and interstitials, which is probably due to the Al-induced local strain field and lattice distortion. The migration energies of interstitials and vacancies exhibit opposite variations, the migration energies of interstitials are increased while that of vacancies are decreased with the Al content. Moreover, the distributions of formation and migration energies of both defects are significantly broadening with increasing Al content, which could further enhance the characteristic effects of HEAs and play a more important role in the irradiation resistances of HEAs. Based on the calculation results, the effects of Al on the irradiation responses of AlxCoCrFeNi are discussed. [ABSTRACT FROM AUTHOR]

We present a machine learning approach to calculating electronic specific heat capacities for a variety of benchmark molecular systems. Our models are based on data from density matrix quantum Monte Carlo, which is a stochastic method that can calculate the electronic energy at finite temperature. As these energies typically have noise, numerical derivatives of the energy can be challenging to find reliably. In order to circumvent this problem, we use Gaussian process regression to model the energy and use analytical derivatives to produce the specific heat capacity. From there, we also calculate the entropy by numerical integration. We compare our results to cubic splines and finite differences in a variety of molecules in which Hamiltonians can be diagonalized exactly with full configuration interaction. We finally apply this method to look at larger molecules where exact diagonalization is not possible and make comparisons with more approximate ways to calculate the specific heat capacity and entropy. [ABSTRACT FROM AUTHOR]

Theories of bulk coacervation of oppositely charged polyelectrolytes (PE) obscure single molecule level thermodynamic details, considered significant for coacervate equilibrium, whereas simulations account for only pairwise Coulomb interaction. Also, studies of effects of asymmetry on PE complexation are rare compared to symmetric PEs. We develop a theoretical model, accounting for all entropic and enthalpic contributions at the molecular level, and the mutual segmental screened Coulomb and excluded volume interactions between two asymmetric PEs, by constructing a Hamiltonian following Edwards and Muthukumar. Assuming maximal ion-pairing in the complex, the system free energy comprising configurational entropy of the polyions and free-ion entropy of the small ions is minimized. The effective charge and size of the complex, larger than sub-Gaussian globules as for symmetric chains, increase with asymmetry in polyion length and charge density. The thermodynamic drive for complexation is found to increase with ionizability of symmetric polyions and with a decrease in asymmetry in length for equally ionizable polyions. The crossover Coulomb strength demarcating the ion-pair enthalpy-driven (low strength) and counterion release entropy-driven (high strength) is marginally dependent on the charge density, because so is the degree of counterion condensation, and strongly dependent on the dielectric environment and salt. The key results match the trends in simulations. The framework may provide a direct way to calculate thermodynamic dependencies of complexation on experimental parameters such as electrostatic strength and salt, thus to better analyze and predict observed phenomena for different sets of polymer pairs. [ABSTRACT FROM AUTHOR]

We explore the relationship between a machine-learned structural quantity (softness) and excess entropy in simulations of supercooled liquids. Excess entropy is known to scale well the dynamical properties of liquids, but this quasi-universal scaling is known to breakdown in supercooled and glassy regimes. Using numerical simulations, we test whether a local form of the excess entropy can lead to predictions similar to those made by softness, such as the strong correlation with particles' tendency to rearrange. In addition, we explore leveraging softness to compute excess entropy in the traditional fashion over softness groupings. Our results show that the excess entropy computed over softness-binned groupings is correlated with activation barriers to rearrangement. [ABSTRACT FROM AUTHOR]

In this paper, we present an in-depth analysis for entropy source based on optical physical unclonable functions (PUFs). The randomness of speckle patterns is elaborated essentially according to its statistical characteristics. Various factors affecting the source of entropy have been analyzed in detail, including wavefront modulation, sensitivity, and universality of the optical PUF, and bit-depth settings of captured speckle patterns. In view of the above considerations, we demonstrate that the entropy source can achieve an ultra-high min-entropy (>0.985 bits/bit) while maintaining a high extraction rate of 75% and also verify its independent and identically distributed nature. These results provide an in-depth and comprehensive understanding of the developed entropy source and offer a firm foundation for its practical use. [ABSTRACT FROM AUTHOR]

Entropy generation analyses of hybrid nanofluids via compliant wall tubes are performed with peristalsis effects in this study. Thermophysical properties of nanofluid are incorporated in mathematical formulations for various shapes of nanoparticles. Convective conditions on the boundary are considered. Momentum and energy equations are modeled and simplified under the lubrication approach. Solutions are calculated numerically using MATHEMATICA. The impact of various related parameters on flow quantities is observed via graphs. The study reveals greater entropy generation for blade-shaped nanoparticles. [ABSTRACT FROM AUTHOR]

In this paper, a novel four-wing chaotic system is constructed based on the Sprott-A system. The novel system contains three nonlinearly quadratic terms, which have rich dynamics such as four-wing hidden attractors, hidden extreme multistability and transient transitions. It is found that this system has high complexity by spectral entropy analysis. In addition, a corresponding hardware analog circuit is designed based on this system by operational amplifiers and multipliers. The experimental results agree with those of the theoretical analysis and confirm that this system is practically feasible. This system will have a good application value in secure communication and cryptography. [ABSTRACT FROM AUTHOR]

A modified Poisson–Nernst–Planck system in a bounded domain with mixed Dirichlet–Neumann boundary conditions is analyzed. It describes the concentrations of ions immersed in a polar solvent and the correlated electric potential due to the ion–solvent interaction. The concentrations solve cross-diffusion equations, which are thermodynamically consistent. The considered mixture is saturated, meaning that the sum of the ion and solvent concentrations is constant. The correlated electric potential depends nonlocally on the electric potential and solves the fourth-order Poisson–Fermi equation. The existence of global bounded weak solutions is proved by using the boundedness-by-entropy method. The novelty of the paper is the proof of the weak–strong uniqueness property. In contrast to the existence proof, we include the solvent concentration in the cross-diffusion system, leading to a diffusion matrix with nontrivial kernel. Then the proof is based on the relative entropy method for the extended cross-diffusion system and the positive definiteness of a related diffusion matrix on a subspace. [ABSTRACT FROM AUTHOR]

This document presents an elementary approach using ε -Poincaré inequality to prove generation of L p -bounds, p ∈ (1 , ∞) , for the homogeneous Landau equation with moderate soft potentials γ ∈ [ − 2 , 0). The critical case γ = − 2 uses an interpolation approach in the realm of Lorentz spaces and entropy. Alternatively, a direct approach using the Hardy-Littlewood-Sobolev (HLS) inequality and entropy is also presented. On this basis, the generation of pointwise bounds p = ∞ is deduced from a De Giorgi argument. [ABSTRACT FROM AUTHOR]

Non-additive measures are important for many applications. In this paper we propose an extension of the non-additive measure using the concept of Kerridge inaccuracy and cumulative Tsallis entropy. Several properties including non-linear transformation, bounds and characterizations are obtained using this measure. We also study different properties of the quantile version of the proposed measure. Finally, we numerically illustrate the usefulness of the measure and its quantile form using kernel density estimators. [ABSTRACT FROM AUTHOR]

In this work, the irradiation response of A 2 Ti 2 O 7 (A represents rare earth elements of Gd, Dy, Ho, Er, Yb and Nd) series ceramics were systematically studied under 3 MeV Au2+ ions. The structural changes pre- and post-irradiation were characterized using X-ray diffraction (XRD), grazing incidence X-ray diffraction (GIXRD) and Raman spectroscopy. After heavy ion irradiation, all the samples undergo structural transformations from ordered pyrochlore to disordered fluorite and then to amorphous phase. The sample surface became fully amorphous when exposed to the maximum irradiation dose. The 5RETO high-entropy pyrochlore exhibits the lowest rate of amorphization during the process of structural transformation. The cation radius ratio and mixed entropy are the primary factors influencing amorphization rate. The cation radius ratio shows a strong positive correlation with the amorphization rate, while the mixed entropy demonstrates a weak negative correlation with the amorphization rate. The cation radius ratio can thus serve as a reliable indicator for predicting the radiation resistance of high-entropy pyrochlore ceramics. [ABSTRACT FROM AUTHOR]

The principal aim of this investigation is to examine the gold and magnesium oxide hybrid nanoparticles in different physical capacities on the water-based hybrid nanofluid and elaborate on an erratic squeezing flow among both infinite plates. Melting effect and thermal radiation depict heat transfer features. Production of the Bejan number and entropy is upward. The explains the governing equations, and the standard transformation is supplied. The numerical solutions are carried out using an efficient finite element method. To analyze difference between heat transfer and its implication in industrial zone, the Nusselt number was arranged in a horizontal pattern. The results showed that a thicker thermal boundary layer increased the Eckert number and the volume fraction of gold nanoparticles. Anyhow, the heat transfer rate by Au–MgO/water was necessarily greater than the Au–water. The obtained results are excellent and vigorously oppose those that are applicable to the literature by the attached position. It was established for hybrid nanofluids to display higher entropy generation rates. The outcomes of this analysis were the consequence of the appraisal of the impact on few required form parameters in heat transfer and consequently on the expansion for industrial use. [ABSTRACT FROM AUTHOR]

The novelty of this paper is examining the impacts of Hall currents on Sisko nanofluid slip flow generated by an exponentially stretching sheet in the existence of entropy generation. Entropy generation assessment, Brownian, thermophoresis and Bejan numbers during convection flow are explored in the presence of the Hall effect. The pertinent parameters are Hall parameter m, a magnetic field parameter M, Brownian motion parameter N b , thermophoresis parameter N t , generalized thermal Biot number γ 1 , generalized velocity slip parameter λ and material parameter of Sisko fluid A. The changes in pertinent parameters on principal and secondary velocities, entropy generation and temperature are discussed. The coefficients of local skin friction, Brownian, thermophoresis and Nusselt/Sherwood numbers are expressed in a tabular structure. Two different kinds of power-law nanofluid, Pseudoplastic (n = 0. 7) and dilatant fluid (n = 1. 5) are considered. The current results exposed that growth in magnetic field parameter diminishes the nanofluid axial velocity and boosts the profiles of temperature, secondary nanofluid velocity and nanoparticle volume fraction. The coefficients of local skin friction are enhanced according to a growth in the magnetic field factor. The Pseudoplastic fluid supports the velocity, temperature and nanoparticle volume fraction profiles compared to the dilatant fluid. The local entropy generation number, Bejan number, local skin friction coefficients and local Nusselt/Sherwood numbers are influenced by the pertinent parameters. [ABSTRACT FROM AUTHOR]

For the first time, Ni 25 Co 20 Cu 10 Fe 25 Mn 20 high entropy alloy (HEA) was employed as a sintering aid for fabrication of ZrB 2 -based ceramics using spark plasma sintering (SPS) process. The mechanical properties, phase evolution, microstructural changes, and the densification mechanisms of ZrB 2 -5 wt% HEA ceramics during the SPS step were scrutinized. The ZrB 2 -5 wt% HEA ceramic, manufactured at 1900 °C, yielded interesting combination of properties, counting a relative density of 96%, a fracture toughness of 6.4 MPa m1/2, and a hardness of 12.6 GPa. According to XRD patterns, there were ZrC and ZrO 2 phases with ZrB 2 matrix in the sintered samples. An unknown phase was also observed in the XRD patterns. Based on the history of the NiCoCuFeMn alloy and separation of Cu within the temperature range of 650–850 °C, that phase was related to CuB. [ABSTRACT FROM AUTHOR]

We report the effect of configurational entropy (CE) on the electrocaloric (EC) effect of Ba x Sr y Ca z (Bi 0.5 Li 0.5) 1- x - y - z TiO 3 (BSCBLT) (0.627≤ x ≤ 0.66, 0.0716≤ y ≤ 0.1993, 0.0145≤ z ≤ 0.1758) ceramics. All samples were designed to show different CE but the same A-site cation average radius, tolerance factor and cationic size disorder. The samples with x ≤ 0.64 show ferroelectric (FE) relaxor behavior, while x ≥ 0.65 are normal FEs. x = 0.65 shows the maximum EC effects among all samples. Both maximum adiabatic temperature change (ΔT m) and CE vary almost in the same way with increasing x. The anomalous enhancement of ΔT m in x = 0.65 with relatively lower CE compared with that in x = 0.64 can be ascribed to an additional contribution of Ba concentration induced FE to relaxor FE transition in BSCBLT. Our results reveal important evidences of enhanced EC effects by CE and suggest that designing FEs or relaxor FEs with high CE might be an effective route to achieve high EC effects. [ABSTRACT FROM AUTHOR]

In this paper, we study the Cauchy problem for the one-dimensional Euler-Poisson (or hydrodynamic) model for semiconductors, where the energy equation is replaced by a pressure-density relation. First, the existence of global entropy solutions is proved by using the vanishing artificial viscosity method, where, a special flux approximate is introduced to ensure the uniform boundedness of the electric field E and the a-priori L ∞ estimate, 0 < 2 δ ≤ ρ ε , δ ≤ M (t) , | u ε , δ | ≤ M (t) , where M (t) could tend to infinity as the time t tends to infinity, on the viscosity-flux approximate solutions (ρ ε , δ , u ε , δ) ; Second, the compensated compactness theory is applied to prove the pointwise convergence of (ρ ε , δ , u ε , δ) as ε , δ go to zero, and that the limit (ρ (x , t) , u (x , t)) is a global entropy solution; Third, a technique, to apply the maximum principle to the combination of the Riemann invariants and ∫ − ∞ x ρ ε , δ (x , t) − 2 δ d x , deduces the uniform L ∞ estimate, 0 < 2 δ ≤ ρ ε , δ ≤ M , | u ε , δ | ≤ M , independent of the time t and ε , δ ; Finally, as a by-product, the known compactness framework [14,29] is applied to show the relaxation limit, as the relation time τ and ε , δ go to zero, for general pressure P (ρ). [ABSTRACT FROM AUTHOR]

In this article, we focus on the application of fractional differential calculus in image processing, specifically in the context of image decoding techniques. The article presents different methods of image decoding based on Riemann–Liouville fractional integration and compares their performance with established methods in the denoising of noisy images. Here we create new fractional masks by using the Middle Point approach method, the Grumwald–Letnikov scheme, the Toufik–Riemann scheme, and the Euler method with the help of the Riemann–Liouville fractional integral operator. The results demonstrate that the suggested algorithms outperform the compared techniques. The paper also suggests that the concepts presented can be applied to other definitions of fractional calculus. The future research goal is to determine the optimal fractional order for a given set of algorithms. [ABSTRACT FROM AUTHOR]

Nowadays, the Internet of Things (IoT) networks provide benefits to humans in numerous domains by empowering the projects of smart cities, healthcare, industrial enhancement and so forth. The IoT networks include nodes, which deliver the data to the destination. However, the network nodes' connectivity is affected by the nodes' removal caused due to the malicious attacks. The ideal plan is to construct a topology that maintains nodes' connectivity after the attacks and subsequently increases the network robustness. Therefore, for constructing a robust scale-free network, two different mechanisms are adopted in this paper. First, a Multi-Population Genetic Algorithm (MPGA) is used to deal with premature convergence in GA. Then, an entropy based mechanism is used, which replaces the worst solution of high entropy population with the best solution of low entropy population to improve the network robustness. Second, two types of Edge Swap Mechanisms (ESMs) are proposed. The Efficiency based Edge Swap Mechanism (EESM) selects the pair of edges with high efficiency. While the second ESM named as EESM-Assortativity, transforms the network topology into an onion-like structure to achieve maximum connectivity between similar degree network nodes. Further, Hill Climbing (HC) and Simulated Annealing (SA) methods are used for optimizing the network robustness. The simulation results show that the proposed MPGA Entropy has 9% better network robustness as compared to MPGA. Moreover, both the proposed ESMs effectively increase the network robustness with an average of 15% better robustness as compared to HC and SA. Furthermore, they increase the graph density as well as network's connectivity. [ABSTRACT FROM AUTHOR]

The flow of ferronanofluid due to a rotating disk finds its significant place in biomedical sciences, pharmaceuticals, electronics, aerodynamics etc. Entropy generation appears in the systems/processes where its minimization is needed because it prohibits the decay of available energy which in turn boosts the efficiency of the associated thermal systems where it matters the most. In view of these added advantages, the flow and heat transfer behavior of ferronanofluid subject to slip, suction, electromagnetic field, Darcy–Forchheimer effect, and viscous dissipation, Ohmic heating and thermal radiation has been explored within this research. In addition, the role of entropy minimization associated with the flow concern has been analyzed. The apposite governing equations are numerically treated via shooting method. The important outcome of the study include infusion of more porous matrix develops controlled rotating flow due to both deformed disks. Rise in slip parameter augments flow velocity for stretched RD while that shows the adverse effect for shrunk RD. Controlled rate of heat transportation due to enhanced convective heating is significant for shrunk RD than that of stretched RD. Further, low Prandtl fluids, low molecular heat conduction and liquid friction yield entropy minimization thereby leading to uplift efficiency of thermal systems. [ABSTRACT FROM AUTHOR]

The nonlinear variability present during steady-state gait may provide a signature of health and showcase one's walking adaptability. Although treadmills can capture vast amounts of walking data required for estimating variability within a small space, gait patterns may be misrepresented compared to an overground setting. Smartphones may provide a low-cost and user-friendly estimate of gait patterns among a variety of walking settings. However, no study has investigated differences in gait patterns derived from a smartphone between treadmill walking (TW) and overground walking (OW). This study implemented a smartphone accelerometer to compare differences in temporal gait variability and gait dynamics between TW and OW. Sixteen healthy adults (8F; 24.7 ± 3.8 years) visited the laboratory on three separate days and completed three 8-minute OW and three TW trials, at their preferred speed, during each visit. The inter-stride interval was calculated as the time difference between right heel contact events located within the vertical accelerometery signals recorded from a smartphone while placed in participants front right pant pocket during walking trials. The inter-stride interval series was used to calculate stride time standard deviation (SD) and coefficient of variation (COV), statistical persistence (fractal scaling index), and statistical regularity (sample entropy). Two-way analysis of variance compared walking condition and laboratory visits for each measure. Compared to TW, OW displayed significantly (p < 0.01) greater stride time SD (0.014 s, 0.020 s), COV (1.26 %, 1.82 %), fractal scaling index (0.70, 0.79) and sample entropy (1.43, 1.63). No differences were found between visits for all measures. Smartphone-based assessment of gait provides the ability to distinguish between OW and TW conditions, similar to previously established methodologies. Furthermore, smartphones may be a low-cost and user-friendly tool to estimate gait patterns outside the laboratory to improve ecological validity, with implications for free-living monitoring of gait among various populations. • Smartphones can enable gait monitoring outside the lab and for clinical purposes. • Treadmills reduce gait variability and dynamics compared to overground setting. • Context of walking must be considered within the interpretation of the results. [ABSTRACT FROM AUTHOR]

Balance deficits are a major concern for people with multiple sclerosis (pwMS). Measuring complexity of motor behaviour can offer an insight into MS-related changes in adaptability of the balance control system when dealing with increasingly complex tasks. Does postural behaviour complexity differ between pwMS at early stages of the disease and healthy controls (HC)? Does postural behaviour complexity change across increasingly complex tasks? Forty-eight pwMS and 24 HC performed four increasingly complex postural tasks with eyes open (EO), eyes closed (EC), on firm (FS) and compliant surface (CS). Lumbar and sternum sensors recorded 3D acceleration, from which complexity index (CI) was calculated using multiscale sample entropy (MSE) in the frontal and sagittal planes. We found that only the complexity index in both planes during the eyes closed on compliant surface (EC-CS) task was significantly lower in pwMS compared to HC. We also found that complexity in pwMS was significantly lower during EC-CS compared to the other three tasks when using both lumbar and sternum sensors. Increasing the complexity of postural tasks reduces the complexity of postural behaviour in pwMS. This paradox may reflect reduced adaptability of the sensorimotor integration processes at early stages of MS. CI can provide a different perspective on balance deficits and could potentially be a more sensitive biomarker of MS progression and an early indicator of balance deficit. • People with MS (pwMS) have balance deficits that are difficult to early detect. • Measuring complexity of postural behaviour provides insights into balance adaptability. • More complex postural task trigger less complex postural behaviours in pwMS. • Reduced complexity can be associated to a diminished adaptability of the balance system. • Complexity during challenging postural tasks can unmask subtle balance deficits in MS. [ABSTRACT FROM AUTHOR]

Modification of materials to achieve specific changes in their physical and chemical properties often involves the substitution of ions. While this process is commonly discussed in structural terms, our recent publication focussed on exploring the thermochemical consequences, including enthalpy, entropy, heat capacity, and formula unit volume, associated with substituting monocharged cations for sodium ions as a reference set. In the current study, we extend our analysis to investigate the consequences of substituting monocharged anions, specifically the halides F−, Br−, and I−, as well as H−, OH−, and NO3−, for chloride anions. This exploration is conducted through least-squares regression analysis of data obtained from 431 chloride ion-exchanged materials. In the case of cation substitutions, the regression trendlines for different substitutions appear to be roughly parallel to each other but vertically displaced. For anion substitutions, however, the trendlines for enthalpy and formula unit volume exhibit a fan-like spread from their data origin. We delve into the reasons behind this observed difference. A detailed analysis of a few outliers is undertaken to identify potential reasons for the discrepancies. These findings contribute to a better understanding of the implications and variations in ion substitutions, shedding light on the intricacies of material modification processes. [ABSTRACT FROM AUTHOR]

Heavy metal concentrations were determined in four different locations: market, abattoir, mechanic village and farmland in Obollo–Afor and its environs. The samples were digested and subsequently analysed using Atomic Absorption Spectrophotometer (AAS). The mean concentration of metals in the soil samples were in the order Fe > Zn > Mn > Cr > Pb > Cu > Ni > Cd. The mean concentration of metals in the effluent samples were in the order Fe > Cr > Ni > Pb > Zn > Mn > Cd > Cd. The mean concentration of the metals in meat samples were in the order Fe > Zn > Cu > Ni > Mn > Cd > Cr > Pb. The mean concentration of metals in the plant samples were in the order Fe > Mn > Zn > Cu > Ni > Cr > Pb > Cd. Cadmium, zinc, chromium and lead were higher than the World Health Organization (WHO) standard for soil while cadmium, copper and zinc were higher than the WHO standard for plant. Iron, zinc, copper, nickel and chromium were higher than the WHO standard for meat while lead, nickel, iron, were higher than the WHO standard for water. Heavy metal pollution index (HPI) and heavy metal evaluation index (HEI) showed low risk for all locations while degree of contamination (Cdeg) revealed medium to high values for all locations except AB7. Consequently, the environment is not safe due to high concentration of these toxic metals. The multivariate analyses unraveled anthropogenic and geogenic sources of the contamination. With this trend of findings from the forensics entropy analysis, it can be said that Obollo Afor is the epicentre of these contaminants and attenuates towards the farmland area. The study therefore recommends effective and efficient environmental management strategy measures to curb this menace. [ABSTRACT FROM AUTHOR]

We study curve-shortening flow for twisted curves in $\mathbb {R}^3$ (that is, curves with nowhere vanishing curvature $\kappa $ and torsion $\tau $) and define a notion of torsion-curvature entropy. Using this functional, we show that either the curve develops an inflection point or the eventual singularity is highly irregular (and likely impossible). In particular, it must be a Type-II singularity which admits sequences along which ${\tau }/{\kappa ^2} \to \infty $. This contrasts strongly with Altschuler's planarity theorem, which shows that ${\tau }/{\kappa } \to 0$ along any essential blow-up sequence. [ABSTRACT FROM AUTHOR]

In the present review work, it is proposed to carry out a bibliographic analysis about the thermal behaviour of the dolomitic mineral. The state of the art of dolomite currently indicates a growing use as a refractory material due to the cheaper alternative it represents compared to other materials such as magnesium oxide. The importance of dolomite apart from its application in the steel industry lies in the fact that it has expanded to other industrial fields such as the production of catalysts, catalyst supports, and industrial effluent purification materials. In these and other applications, understanding the thermal behaviour of the material is necessary to evaluate the feasibility of application. In this review, the different experimental proposals developed over time in terms of thermal behaviour are studied, emphasizing the reaction mechanisms that have been proposed in different investigations. [ABSTRACT FROM AUTHOR]

We consider the problem of clustering functional data according to their covariance structure. We contribute a soft clustering methodology based on the Wasserstein–Procrustes distance, where the in‐between cluster variability is penalized by a term proportional to the entropy of the partition matrix. In this way, each covariance operator can be partially classified into more than one group. Such soft classification allows for clusters to overlap, and arises naturally in situations where the separation between all or some of the clusters is not well‐defined. We also discuss how to estimate the number of groups and to test for the presence of any cluster structure. The algorithm is illustrated using simulated and real data. An R implementation is available in the Appendix S1. [ABSTRACT FROM AUTHOR]

The oxidation performance of CoCrFe2Ni0.5 HEA borided through a powder-pack boriding process was investigated at 900 °C for 120 h. The boriding process at 900 °C for 6 h resulted in the formation of a two-zone structure: the outmost part contained a Ni2Si layer and the inner part consisted of a MB/M2B layer. The borided alloy displayed better oxidation resistance with the least oxidation rate constant value of 0.0383 (mgn cm−2n h−1). Moreover, this alloy rendered a continuous oxide layer that was denser, more compact, and contained fewer defects, which confirmed the improvement in oxidation resistance. The Ni2Si layer plus the boride layer was responsible for the enhanced oxidation performance of borided alloy. [ABSTRACT FROM AUTHOR]

The present investigation is on examination of the natural convection and entropy generation considering the heatlines visualization of nanofluid I‐shaped enclosure with two corrugated walls considering inner rectangular heater of three different heights. The influence of Brownian motion along with thermophoresis had been implemented using Inhomogeneous two‐phase model of nanofluid. The governing equations were solved numerically using COMSOL software. Influence of Rayleigh number (103≤Ra≤105) $({10}^{3}\le {Ra}\le {10}^{5})$, Buoyancy ratio number (0.1≤Nr≤4) $(0.1\le {Nr}\le 4)$, Lewis number (2≤Le≤8) $(2\le {Le}\le 8)$, heater length (0.25≤H≤0.75) $(0.25\le H\le 0.75)$. The results indicate that the influence of Lewis number on heat transfer bettering is stronger at high Rayleigh number (Ra=105) $({Ra}={10}^{5})$ while its impact is negligible at a lower value of Rayleigh number (conduction mode). In addition, the total entropy generation gets its highest value at Lewis number (Le=1) $({Le}=1)$. Bejan number, fluid flow strength and heat rate increase as the rectangular heater height increases. Also, higher heat transfer augmentation is taken when the heater height is (H=0.5) $(H=0.5)$ while increasing the heater height to (H=0.75) $(H=0.75)$ leads to more total entropy generation. The impact of heater height on total entropy generation is highly affected by Rayleigh number as increasing the heater height from (H=0.25) $(H=0.25)$ into (H=0.75) $(H=0.75)$, total entropy generation increases by 60% $60 \% $ at Ra=103) ${Ra}={10}^{3})$ while it increases by 74.62% $74.62 \% $ at (Ra=105) $({Ra}={10}^{5})$. [ABSTRACT FROM AUTHOR]

This study provides a chemical mechanism reduction strategy based on entropy production analyses in both auto-ignition and laminar flames, which enhances the predictive accuracy for laminar burning velocities. In addition to chemical reactions, other irreversible sources causing entropy generation, such as mass diffusion and heat conduction, are considered in the modified approach. Specifically, initial skeletal mechanisms are first generated based on important reactions that contribute to entropy production in auto-ignition processes. Mechanism patches are then constructed to include important species and reactions, which contribute to entropy production from mass diffusion and heat conduction in laminar premixed flames beyond the pre-defined thresholds, respectively. Finally, the initial skeletal mechanisms and mechanism patches are combined to establish the final skeletal mechanisms. In this way, two final skeletal mechanisms for n-dodecane, consisting of 162 species and 2276 reactions, and 160 species and 1916 reactions, respectively, are developed from the detailed POLIMI mechanism with 451 species and 17,848 reactions. The two final skeletal mechanisms are proven to accurately predict laminar burning velocities and entropy production in n-dodecane flames with insignificant variations in the simulation results compared to the detailed mechanism, while their accuracy in predicting ignition delay times relies on the initial skeletal mechanisms. Specifically, the reduced mechanism with 160 species and 1916 reactions exhibits less satisfactory performance in predicting ignition delay compared to that with 162 species and 2276 reactions, indicating that a lower threshold is required to generate the initial skeletal mechanism through entropy production analysis of homogeneous auto-ignition processes. Additionally, compared with the reduced mechanisms with similar sizes obtained with other mechanism reduction strategies, the two final skeletal mechanisms accurately capture the characteristics of laminar burning velocities and ignition delay times, with similar calculation time required. [ABSTRACT FROM AUTHOR]

This work looks at developing an object-driven decision support system (DSS) model with the goal of improving the prediction accuracy of the present expert-driven DSS model in assessing groundwater potentiality. The database of remote sensing, geological, and geophysical information was constructed using the technological efficiency of GIS, data mining, and programming tools. Groundwater potential conditioning factors (GPCF) extracted from the datasets include lithology (Li), hydraulic conductivity (K), lineament density (Ld), transmissivity (T), and transverse resistance (TR) for groundwater potentiality mapping in a typical hard rock multifaceted geologic setting in south-western Nigeria. A Python-based entropy approach was used to objectively weight these factors. The weightage findings determined that the greatest and lowest given values for Ld and K were 0.6 and 0.03, respectively. The produced Python-based PROMETHEE-Entropy model algorithm was born through combining the weight findings with the Python-based PROMETHEE-II method. The groundwater potentiality model (GPM) map of the area was created using the model algorithm's outputs on the gridded raster of GPCF themes. Based on the suggested approach, the validated results of the created GPM maps using the Receiver Operating Characteristic (ROC) curve technique yielded an accuracy of 86%. An object-driven DSS model was created using the approaches that were used. The created object-driven model is a viable alternative to existing approaches in groundwater hydrology and aids in the automation of groundwater resource management in the research region. [ABSTRACT FROM AUTHOR]