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First-principles calculations have been employed here to investigate the optical and electrical properties of experimentally synthesized Mo(W)S2-SnO2 vdW heterostructures [J. Phys. Chem. C 2020, 124, 1, 647–652, Chem. Phys. 2019, 525, 110398]. Rigorous dynamical stability assessments confirm structural robustness, evident in phonon dispersion and AIMD simulations at 500 K. The interfacial binding energy values reflect the stability of our simulated heterostructures. With intrinsic type-II band alignment and direct band gaps of 1.21eV (MoS2-SnO2) and 1.003eV (WS2-SnO2), these heterostructures emerge as promising candidates for high-efficiency optical devices. Higher static dielectric constants in comparison with numerous heterostructures signify low charge carrier recombination rates, enhancing practical appeal. Optical analyses reveal substantial visible and ultraviolet (UV) spectrum absorption, while MoS2-SnO2 and WS2-SnO2 heterostructures exhibit photoelectric conversion efficiencies of 15.08% and 13.65%. A thorough examination of optical characteristics provides a comprehensive understanding of positioning Mo(W)S2-SnO2 vdW heterostructures for advanced optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study aims to propose a central composite design (CCD) combined with response surface methodology (RSM) to create a statistical experimental design. A new parametric optimization of entropy generation is presented. The flow behavior of magnetohydrodynamic hybrid nanofluid (HNF) flow through two flat contracting expanding plates of channel alongside radiative heat transmission was considered. The lower fixed plate was externally heated whereas the upper porous plate was cooled by injecting a coolant fluid with a uniform velocity inside the channel. The resulting equations were solved by the Homotopic Analysis Method using MATHEMATICA 10 and Minitab 17.1. The design consists of several input factors, namely a magnetic field parameter ( M ), radiation parameter ( N ) and group parameter ( B r / A 1 ). To obtain the values of flow response parameters, numerical experiments were used. Variables, especially the entropy generation ( N e ), were considered for each combination of design. The resulting RSM empirical model obtained a high coefficient of determination, reaching 99.97% for the entropy generation number ( N e ). These values show an excellent fit of the model to the data. [ABSTRACT FROM AUTHOR]

Peristaltic transport of couple stress fluid with heat transfer is investigated through flexible walls of the channel furnished with hair‐like structures. Locomotion of biological fluid is the result of the simultaneous propagation of metachronal waves (MCWs) and peristaltic waves. MCW emerges due to multi‐movement of cilia, while the elastic‐walls of the channel are responsible for the peristaltic wave. The two‐dimensional rheological flow experiences the resistive behavior of applied magnetic fields, besides, the role of viscous dissipation and entropy generation. A closed‐form solution is achieved for the nonlinear coupled differential equation, which is vetted through graphs. Finally, the theoretical analysis introduces the manufacture of a ciliate bronchial tube that can efficiently; remove mucus out of the lungs and bloodstream. [ABSTRACT FROM AUTHOR]

The flow of heat transfer study of carbon nanotubes (CNTs)–water nanofluid over vertical truncated wavy cone is considered. The present boundary layer power law fluid is analyzed near the truncated wavy cone. The considered cone is wavy in physical configuration and placed in a vertical direction. Moreover, nanosized particles of CNTs suspended into water (base fluid) are transporting in two directions, which are modeled by using Boussinesq's approximation. Coordinate transformation is applied in order to shift the wavy surface to a flat surface. Then governing equation dealing with the momentum of nanofluid along with thermal stratification are reduced in dimensionless form by using appropriate transformation. Results point out that the thickness of thermal boundary layer decreases by increasing the value of volume fraction of carbon nanotubes. Finally, the obtained solution is related through a graphical survey, and it is inferred that the investigation is in good accordance with the current literature. [ABSTRACT FROM AUTHOR]

Desiccated coconut waste (DCW) is an agricultural waste that originates from the coconut milk processing industry. In this study, it was utilized for the removal of copper (Cu(II)) and nickel (Ni(II)) via adsorption process. The physicochemical characterization of the DCW adsorbent shows that the adsorbent have a surface area of 6.63 m²/g, have high elemental carbon content and existences of important functional groups on its surface. The adsorptive capability of DCW adsorbent in removing the heavy metal were conducted in batch studies. DCW adsorbent performed highest Ni(II) and Cu(II) adsorption capacity at pH 6, where equilibrium is achieved at 450 minutes. The kinetic analysis showed the adsorption agreed with pseudo-second order kinetic model, indicating the Cu(II) and Ni(II) adsorption were a chemical adsorption, limited by the film diffusion. The DCW adsorbent still retained its effective adsorption capacity after 2 adsorption-desorption cycles, which is one of the excellent criteria of a good adsorbent for an adsorption process. [ABSTRACT FROM AUTHOR]

At the end of 19th century, the modification of silica has brought revolution in the field of nanocomposites and gained the attention of researchers again by the development of the mesoporous silica class. Silica when used with elastomers provides distinctive characteristics merging the superior properties of inorganic fillers, such as hardness, increased thermal strength, and mechanical stability along with the processability, elasticity, and plasticity of the organic polymers. When carbon black is treated with elastomers instead of silica, it provides greater level of reinforcement because the surface of silica is polar and hydrophilic, but it has greater tendency to adsorb moisture, which affects the ionization of silanol groups. The reason behind switching to silica is adverse effects of carbon black on environment. When silica is added in greater amount, it increases the viscosity of rubbers significantly. The high viscosity causes the processing extra difficult by generating excessive wear and tear over the processing equipment. The increase in viscosity is associated with the strong interaction among the silica particles. It has also been reviewed that the use of silica as filler in elastomers was hindered as far as bifunctional organosilanes were discovered. These are referred to as surface-modifying materials and are initiators for treating silica surfaces to make the filler compatible and friendly to elastomers. [ABSTRACT FROM AUTHOR]

In this paper, we communicate a new type of Auger-free luminescence (AFL) compounds, alkali tin fluorides ASnF3 (A = Na, K, Rb and Cs). The luminescence in these compounds originates due to the electron transition from the top valence band (VB) of tin- orbital to the outermost core levels of halogen, i.e., halogen- orbital (- transitions). The AFL of these compounds is expected to be of L-type. Furthermore, the electronic band structures and optical properties such as dielectric functions, refractive index and energy loss function are also investigated using ab initio calculations. [ABSTRACT FROM AUTHOR]

In this work, different quantities of TiO 2 incorporated into TiO 2 -KIT6 nanostructured catalysts were considered to improve the photocatalytic abatement of volatile organic compounds (VOCs; ethylene, propylene) at ambient temperature. The best optimized activity and stability of the catalysts toward(s) ethylene and propylene degradation has been shown for 30 wt% TiO 2 , while the worst conversion has been observed for a 90 wt% TiO 2 loading. This was likely due to the dispersion and stabilization of the anatase TiO 2 with 30 wt% on KIT-6, which in turn allowed more VOCs adsorption and better light penetration than 90% TiO 2 /KIT-6 in which it showed a bulk phase and large agglomerates with light penetration limitations. VOC abatement has been found to be not only influenced directly by the dispersed TiO 2 contents but also by the calcination temperatures, and 500 °C has been found to be the best calcination condition to achieve the highest propylene conversion. The optimized nanostructured photocatalyst developed for ethylene and propylene, could also be promising candidate for other VOCs and different applications. [ABSTRACT FROM AUTHOR]

Mixed convection flow of two layers nanofluid in a vertical enclosure is studied. The channel consists of two regions. Region I is electrically conducting while Region II is electrically non-conducting. Region I is filled with base fluid water with copper oxides nanoparticles and Region II is filled with base fluid kerosene oil with iron oxides. The simultaneous effects of electro-magnetohydrodynamics and Grashof number are also taken into account. The governing flow problem consists of nonlinear coupled differential equations which is tackled using analytical technique. Analytical results have been obtained by the homotopy analysis method (HAM). The results for the leading parameters, such as the Hartmann numbers, Grashof numbers, ratio of viscosities, width ratio, volume fraction of nanoparticles, and the ratio of thermal conductivities for three different electric field scenarios under heat generation/absorption were examined. It is found that the effect of the negative electric load parameter assists the flow while the effect of the positive electric load parameter opposes the flow as compared to the case when the electric load parameter is zero. All outcomes for significant parameters on velocity and temperature are discussed graphically., (© 2023 IOP Publishing Ltd.)