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Abstract A two‐dimensional conservative nonhydrostatic (NH) model based on the compressible Euler system has been developed in the Cartesian (x, z) domain. The spatial discretization is based on a Godunov‐type finite‐volume (FV) method employing dimensionally split fifth‐order reconstructions. The model uses the explicit strong stability‐preserving Runge‐Kutta scheme and a split‐explicit method. The time‐split approach is generally based on the split‐explicit method, where the acoustic modes in the Euler system are solved using small time steps, and the advective modes are treated with larger time steps. However, for the Godunov‐type FV method this traditional approach is not trivial for the Euler system of equations. In the present study, a new strategy is proposed by which the Euler system is split into three modes, and a multirate time integration is performed. The computational efficiency of the split scheme is compared with the explicit one using the FV model with various NH benchmark test cases.

The Jablonowski test case is widely used for debugging and evaluating the numerical characteristics of global dynamical cores that describe the fluid dynamics component of Atmospheric General Circulation Models. The test is defined in terms of a steady-state solution to the equations of motion and an overlaid perturbation that triggers a baroclinically unstable wave. The steady-state initial conditions are zonally symmetric. Therefore, the test case design has the potential to favor models that are built upon regular latitude-longitude or Gaussian grids. Here we suggest rotating the computational grid so that the balanced flow is no longer aligned with the computational grid latitudes. Ideally the simulations should be invariant under rotation of the computational grid. Note that the test case only requires an adjustment of the Coriolis parameter in the model code. The rotated test case has been exercised by six dynamical cores. In addition, two of the models have been tested with different vertical coordinates resulting in a total of eight model variants. The models are built with different computational grids (regular latitude-longitude, cubed-sphere, icosahedral hexagonal/triangular) and use very different numerical schemes. The test case is useful for debugging, assessing the degree of anisotropy in the numerical methods and grids, and evaluating the numerical treatment of the pole points since the rotated test case directs the flow directly over the geographical poles. It thereby challenges the polar treatments like polar filters in some models.

Densities (ρ), speeds of sound (u), and viscosities (η) for three binary mixtures of allyl alcohol with 3-amino-propan-1-ol, 2-amino-2-methyl-propan-1-ol (aminomethyl propanol), and 1-amino propan-2-ol (isopropanol amine) were calculated at temperatures ranging from 303.15 to 313.15K and at atmospheric pressure over the entire composition range. Experimental measurements were used to calculate the excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of the activation of viscous flow. Partial molar properties and partialmolar properties at infinite dilution are also calculated. The Prigogine–Flory–Patterson (PFP) theory is applied to identify the predominant molecular interaction. The results of the Jouyban–Acree model are discussed in terms of the mean relative deviation (MRDs) and individual relative deviation (IRD) between the calculated and experimental parameters as an accuracy criterion. FTIR studies have also been added to confirm the experimental findings of the investigated mixtures. [ABSTRACT FROM AUTHOR]

Excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy for activation of viscous flow for binary mixtures of propargyl alcohol (J) with benzyl aldehyde (J1), benzylamine (J2) and benzyl alcohol (J3) components with selected compositions were determined from the measured values of densities (ρ), viscosities (η), and speeds of sound (u) of pure components and their mixtures from 303.15 K to 313.15 K. The effect of various functional groups on the excess properties has been discussed in terms of attractive forces between the components. The results of the Jouyban-Acree model are discussed in terms of the mean relative deviation and individual relative between the calculated and experimental densities, speed of sound, and viscosities as an accuracy criterion.FTIR studies have also been added to confirm the experimental findings of the investigated mixtures [ABSTRACT FROM AUTHOR]

Densities (ρ), speeds of sound (u), and viscosities (η) for three binary mixtures of 4-Hydroxy-4-methyl-pentan-2-one with 3-amino-propan-1-ol, 2-amino-2-methyl-propan-1-ol, and 1-amino propan-2-ol were calculated at temperatures ranging from 303.15 to 313.15 K and atmospheric pressure over the entire composition range. Experimental measurements were used to calculate the excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of the activation of viscous flow. Partial molar properties and infinite dilution molar partial properties are also calculated for each binary system. Heteroassociates molecules forming complexes and chemical forces with specific interactions can be discussed from the results. The Prigogine–Flory–Patterson theory is used to identify the most important interaction. The results of the Jouyban–Acree model are discussed in terms of the mean relative deviation and individual relative between the calculated and experimental densities, speed of sound, and viscosities as an accuracy criterion. FTIR studies confirm the experimental findings of the investigated mixtures. [ABSTRACT FROM AUTHOR]

The thermodynamic and transport properties of binary mixtures of N-methyl benzyl amine (NMBA) with halo methane compounds at temperatures from 303.15 K to 313.15 K were investigated. The study analysed the excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy for activation of viscous flow using measured densities (ρ), viscosities (η), and speeds of sound (u). The research also examined the impact of the inductive effect on excess properties concerning intermolecular attractive forces between the respective constituents. Furthermore, the Jouyban–Acree model was employed to correlate density, speed of sound, and viscosity with composition and obtained good agreement. [ABSTRACT FROM AUTHOR]

Graphene, a remarkable material known for its exceptional properties, can be efficiently produced through environmentally friendly methods using renewable resources and eco‐friendly solvents. Recent studies have highlighted the potential of leaf extracts as effective reducing and stabilizing agents in converting graphene oxide (GO) to graphene. This paper presents a green and cost‐effective approach for the effective deposition of silver nanoparticles (Ag NPs) onto the reduced graphene oxide (RGO) nanosheets. The process involves the co‐reduction of GO and AgNO3 in water using Moringa olifera leaf extract, resulting in the formation of a nanocomposite termed reduced graphene oxide‐silver (Ag‐RGO). The formation of RGO and Ag NP is confirmed through UV‐visible spectroscopy, XRD, and Raman spectroscopy techniques. TEM images revealed the morphology of the nanocomposite, depicting 2‐dimensional graphene sheets adorned with Ag NPs. FT‐IR analysis confirmed the removal of oxygenated functional groups from GO, indicating graphene formation. The synthesized Ag‐RGO nanocomposite exhibited significant catalytic, antioxidant, and electrochemical properties. This study underscores the utilization of natural ingredients as sustainable alternatives for producing multifunctional graphene‐silver nanocomposites. [ABSTRACT FROM AUTHOR]

Excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy of activation of viscous flow for binary mixtures of Hexylene glycol (2-methyl-2,4-pentanediol- or MPD) with 1-butanol (J1), 2-butanol (J2) and 2-methyl-2-propanol (J3) components selected compositions were determined from the measured values of densities (ρ), viscosities ($\eta $ η), and speeds of sound (u) of pure components and their mixtures from 303.15 K to 313.15 K. The results are analysed in terms of intermolecular interactions or hydrogen bonding or hetero-association interactions in the binary mixtures. Finally, the Prigogine-Flory-Patterson (PFP) Theory is applied to identify the most predominant molecular interaction. Using Jouyban–Acree model, results are discussed in terms of mean relative deviation (MRDs) and individual relative deviation (IRD) between calculated and experimental densities, speeds of sound and viscosities as an accuracy criterion. [ABSTRACT FROM AUTHOR]

Densities, ρ, and speeds of sound, u, of binary liquid mixtures of diethyl carbonate with 1,2-dichlorobenzene, 1,3-dichlorobenzene and 1,2,4-trichlorobenzene have been measured over the entire range of composition at 303.15 K, 308.15 K, 313.15 K and 318.15 K and at atmospheric pressure. From the experimental data of the density and speed of sound, the excess properties such as excess molar volume, $V_m^E$ V m E , excess isentropic compressibility, $\kappa _s^E$ κ s E , excess molar isentropic compressibility, $K_{s,m}^E$ K s , m E , excess speed of sound, uE, and excess isobaric thermal expansion, $\alpha _p^E$ α p E , have been calculated. For better knowledge of the solute and solvent interaction, excess partial molar volumes, $\bar V_{{\rm{m,1}}}^{\rm{E}}$ V ˉ m , 1 E and $\bar V_{{\rm{m,2}}}^{\rm{E}}$ V ˉ m , 2 E , and excess partial molar volumes, $\bar V_{{\rm{m,1}}}^{{\rm{^\circ E}}}$ V ˉ m , 1 ∘ E and $\bar V_{{\rm{m,2}}}^{{\rm{^\circ E}}}$ V ˉ m , 2 ∘ E of the components at infinite dilution have been measured. All the excess parameter values have been fitted using the Redlich–Kister polynomial smoothing equation. The calculated excess values have been analysed in terms of molecular interactions and structural effects. [ABSTRACT FROM AUTHOR]