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Thin-walled micro-holes are frequently used in aerospace components to achieve specific functions, such as heat dissipation and filtration. However, traditional manufacturing technologies face difficulties in achieving precision machining of these holes due to deformation caused by cutting force or heat. Laser machining is a highly flexible and efficient advanced processing technology that aims to achieve precise machining of thin-walled holes. However, it is important to note that the thermal energy generated by the laser can cause deformation of the thin walls. To address these issues, this paper proposes a process that combines laser and backside electrochemical composite machining. The model for laser electrochemical composite processing after through-hole formation suggests that the laser's temperature rise effect on the electrolyte can significantly enhance the efficiency of electrochemical processing. Furthermore, the laser exerts a micro-zone stirring effect on the electrolyte in the processed micro-zone, which promotes the liquid-phase mass transfer process during the electrochemical reaction. Furthermore, a one-way experiment was conducted to investigate the effects of the main laser parameters on the processing results. The results indicated that higher laser power, as well as lower laser frequency and scanning speed, significantly reduced the edge damage and pore taper of the processed micro-holes. The language used is clear, concise, and objective, adhering to a formal register and avoiding biased or ornamental language. Technical terms are consistently used and explained when first introduced. The text is grammatically correct and free from spelling and punctuation errors. Furthermore, this process has significantly reduced the oxygen content and surface roughness of the sidewalls of the micro-holes. [ABSTRACT FROM AUTHOR]

This article investigates the relaxation dynamics of the ionized 2a1 state of a water molecule within a water dimer. The study was motivated by findings from two previous pieces of research that focused on the relaxation behaviors of the inner-valence ionized water dimer. The present study discloses an observation indicating that water dimers display specific fragmentation patterns following inner-valence ionization, depending on the position of the vacancy. Vacancies were created in the 2a1 state of the proton-donating water molecule (PDWM) and proton-accepting water molecule (PAWM). Utilizing Born–Oppenheimer molecular dynamics simulations, the propagation of the 2a1 ionized state was carried out for both scenarios. The results revealed proton transfer occurred when the vacancy resided in the PDWM, accompanied by the closing of decay channels for O–H bond distance (RO–H) > 1.187 Å (matching Richter et al.'s findings). Conversely, when vacancy was on PAWM, we observed no closing of decay channels (aligning with Jahnke et al.'s findings). This difference translates to distinct fragmentation pathways. In PDWM cases, 2a1 state ionization leads to H3O+ −OH• formation. In contrast, PAWM vacancies result in decay pathways leading to H2O+–H2O+ products. [ABSTRACT FROM AUTHOR]

We have investigated Interparticle Coulombic Electron Capture (ICEC) using an ab initio approach for two systems, H+ + H2O and H + H2O+. In this work, we have determined the contribution of virtual photon exchange and electron transfer to the total ICEC cross section as a function of the distance between the charged and neutral particles. Furthermore, we have shown that the relative orientation of the electron acceptor and neighbor systems affects the magnitude of the ICEC cross sections by at least two orders at relatively small distances. This geometry dependence, present even for distances as large as 10 a0, is due to the electron transfer contribution. The relative magnitude of each contribution to ICEC seems to depend on the system studied. By replacing the projectile electron with a positron, we have confirmed that electron transfer also takes place in positron collisions and that the charge of the projectile has a noticeable effect on the process, particularly at low scattering energies. [ABSTRACT FROM AUTHOR]

The main target of this article is to analyze the role of activation energy and thermal radiation effects on the bioconvective peristaltic transport of Sutterby nanofluid in a two-dimensional flexible porous channel with heat and mass transfer. Also, the consequences of Hall current, heat source, and complaint wall properties along with an inclined magnetic field are taken into consideration. The proposed system of governing equations is simplified by using lubrication approximation and solved numerically using MATLAB's bvp5c solver. Further, numerical observations are analyzed to figure out the consequence of different physical parameters on the flow characteristics. According to the observations, it is identified that the Sutterby nanofluid velocity declines with the climb in the damping force parameter, while it enhances with the upsurge in the Darcy number. The Sutterby fluid temperature profile strengthens when the influence of the heat generation and Brinkman number increase, while it depicts the reverse effect with the elevation in the fluid parameter and radiation parameter. The temperature ratio and activation energy parameters were found to have a significant impact on the fluid concentration. The volume of the trapped fluid bolus is an enhancing function of the channel's non-uniformity parameter. Moreover, current work reveals its applicability to recognize the hemodynamic flow analysis and other biofluid movements in the human body and industrial sectors. [ABSTRACT FROM AUTHOR]

This study illustrates the successful achievement of tunable defect bands in one-dimensional defective phononic crystals (PnCs) through the incorporation of piezoelectric defects with synthetic negative capacitances (SNCs) for the first time. The efficacy of SNCs in creating tunable bandpass filters across a broad frequency range is thoroughly examined using the proposed analytical and numerical models. A newly developed electroelastically coupled transfer matrix that incorporates SNCs is presented, considering either series or parallel connection between bimorph piezoelectric elements. Defect band and transmittance analyses are conducted using the transfer matrix and S-parameter methods. Two key findings emerge from this investigation. First, when the total equivalent capacitance of the bimorph piezoelectric elements and SNC becomes zero, the defect band representing the point-symmetric defect-mode shape can be customized throughout the entire phononic bandgap. Second, the constant transmittance value, resembling short-circuit conditions, highlights the remarkable ability of SNCs to tune defect bands without energy dissipation, paving the way for fully tunable bandpass filters. To propel this research forward, future investigations could explore expanding the design space with double defects, adopting enhanced modeling techniques to account for lateral and shear effects, developing a control algorithm for the automatic optimization of SNC values in actively tunable bandpass filters, and incorporating artificial intelligence into design methods for piezoelectric defects with electrical connections. [ABSTRACT FROM AUTHOR]

Understanding the ignition and dynamic processes for the combustion of hydrate is crucial for efficient energy utilization. Through reactive force field molecular dynamics simulations, we studied the high-temperature decomposition and combustion processes of methane hydrates in a pure oxygen environment. We found that at an ignition temperature of 2800 K, hydrates decomposed from the interface to the interior, but the layer-by-layer manner was no longer strictly satisfied. At the beginning of combustion, water molecules reacted first to generate OH•, followed by methane oxidation. The combustion pathway of methane is C H 4 → CH 3 • → C H 3 O • → C H 2 O → H C • O → HCO O • → CO (C O 2 ). During the combustion process, a liquid water layer was formed between melted methane and oxygen, which hindered the reaction's progress. When there is no heat resistance, oxygen will transform into radicals such as OH• and O•, which have faster diffusion rates, allowing oxygen to conveniently cross the mass transfer barrier of the liquid water layer and participate in the combustion process. Increasing the amount of OH• may cause a surge in the reaction. On the other hand, when significant heat resistance exists, OH• is difficult to react with low-temperature hydrate components, but it can transform into O• to trigger the oxidation of methane. The H• generated has a sufficient lifetime to contact high-temperature oxygen molecules, converting oxygen into radicals that easily cross the water layer to achieve mass transfer. Therefore, finding ways to convert oxygen into various radicals is the key to solving the incomplete combustion of hydrates. Finally, the reaction pathways and microscopic reaction mechanisms of each species are proposed. [ABSTRACT FROM AUTHOR]

Flow of a fluid past a body is a very complicated phenomenon. Computational fluid dynamics is used for studying the characteristics of flow past an array of hemispherical protrusions that is disposed on the wall surfaces of a millisecond microchannel reactor. Protrusions can be used to improve the transport processes involved, but the causes of the phenomena are still incompletely understood. Parametric analyses are performed under different sets of circumstances to delineate the role of geometric features and operation conditions in reactor performance. Dimensionless quantities are used to simplify the characterization of the reactor system with multiple interacting transport phenomena. The mechanisms involved in the intensified processes are analysed, and performance improvement recommendations are presented. The results indicate that the protruded reactor behaves effectively and good yields can be obtained with only milliseconds residence of the mixtures within the channels. The reactor offers the unique advantage for hydrogen production from methanol in that process intensification is realized while preserving the energy balance between the exothermic and endothermic processes. However, the flow rates must be adjusted as needed to maximize production of hydrogen and minimize pressure drops. The momentum diffusivity is more dominant around the protrusion regions than in the other regions. The thermal diffusivity is more dominant in the protruded channels than in the flat channels. The results have implications for hydrogen production and beyond for the study of transport phenomena in microchemical systems.

We present a method, based on the classical Green-Kubo theory of linear response, to compute the heat conductivity of extended systems, leveraging energy-density, rather than energy-current, fluctuations, thus avoiding the need to devise an analytical expression for the macroscopic energy flux. The implementation of this method requires the evaluation of the long-wavelength and low-frequency limits of a suitably defined correlation function, which we perform using a combination of recently-introduced cepstral-analysis and Bayesian extrapolation techniques. Our methodology is demonstrated against standard current-based Green-Kubo results for liquid argon and water, and solid amorphous Silica, and compared with a recently proposed similar technique, which utilizes mass-density, instead of energy-density, fluctuations. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐metal batteries (AZMBs) represent a promising frontier in battery technology, offering sustainable and safe alternatives to traditional non‐aqueous batteries. Despite their potential, understanding the kinetics of zinc electrodeposition—a critical factor in AZMB performance—remains underexplored. Utilizing voltammetry on ultramicroelectrodes, we investigate how scan rate influences key processes of nucleation and growth during Zn2+ electrodeposition. The findings highlight the efficacy of the Butler‐Volmer formulation in capturing electron‐transfer kinetics, contrasting with complex electron transfer kinetic models used for non‐aqueous battery chemistries. We clearly demonstrate that there is a strong dependence of scan rate on the measured value of kinetic parameters (exchange current). To accurately probe the charge transfer kinetics, it is essential to apply fast scan voltammetry to decouple the influence of mass transfer, ensuring that the measured current is independent of the scan rate. Furthermore, by studying a model electrolyte additive, the intricate balance between charge transfer and mass transfer dynamics is unveiled, and this information is crucial for enhancing the stability of zinc metal anodes. These insights pave the way for developing advanced electrolyte and current collector formulations, promising enhanced cyclability and sustainability in zinc metal batteries. [ABSTRACT FROM AUTHOR]

The random motion (the diffusion) of guest molecules in nanoporous host materials is key to their manifold technological applications and, simultaneously, a ubiquitous phenomenon in nature quite in general. Based on a specification of the different conditions under which molecular diffusion in nanoporous materials may occur and of the thus resulting relevant parameters, a survey of the various ways of the measurement of the determining parameters is given. Starting with a condensed introduction to the respective measuring principles, the survey notably includes a summary of the various parameters accessible by each individual technique, jointly with an overview of their strengths and weaknesses as well as of the respective ranges of observation. The presentation is complemented by basic relations of diffusion theory and molecular modeling in nanoporous materials, illustrating their significance for enhancing the informative value of each measuring technique and the added value attainable by their combination. By providing guidelines for the measurement and reporting of diffusion properties of chemical compounds in nanopores, the document aims to contribute to the clarification and standardization of the presentation, nomenclature, and methodology associated with the documentation of diffusion phenomena in nanoporous materials serving for catalytic, mass separation, and other relevant purposes. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting is crucial for the decarbonization of industrial processes and the coupling of renewable energy sources. Evaluation of individual HER and OER contributions to the transfer process is essential for optimizing electrolysis system performance. This study uses nickel-cobalt layered double hydroxide (NiCo-LDH) as a solid-state redox mediator (SRM), achieving efficient H 2 and O 2 separation. This study provides an in-depth analysis of kinetic and ion/charge/mass transfer mechanisms linked to various characteristic impedances in alkaline decoupled water electrolysis (DWE) system by integrating Electrochemical Impedance Spectroscopy (EIS) and Distribution of Relaxation Times (DRT) methods. The characteristic frequency evolution is consistent with the charge-discharge state of SRM and mass transfer frequency is related to the bubble size and gas diffusion rate of electrocatalysts at different current densities. The charge transfer R ct dominates the total polarization impedance in decoupled HER, and mass transfer R m decreases remarkably in decoupled OER. OER shows lower R ct with Fe species existence and lower total polarization impedance than HER. R m in decoupled HER increases by 38.24% and OER by 29.82% during prolonged decoupled test. This study provides valuable insights into the impedance contributions and kinetic mechanisms through novel electrolysis approaches, guiding further optimization of decoupled electrolyzer and electrode. [Display omitted] • High mass loading NiCo-LDH showed excellent decoupling performance. • The DRT method identified different electrochemical processes in DWE. • Kinetic and transfer analysis of electrode contributions in DWE system. • Explain the reasons for the impedance variation during the long-term DWE test. • Achieve continuous and stable HER/OER decoupling at high current densities. [ABSTRACT FROM AUTHOR]

The slow kinetics of oxygen evolution reactions (OER) have impeded the advancement of water splitting technology. Therefore, developing active, stable, and cost-effective electrocatalysts for the OER is crucial. In this study, we present the preparation of a porous Ni–Al rich phase high entropy alloy via the converse selective phase dissolution (CSPD) method. The research findings demonstrate that Fe–Cr rich phase can be removed in aqua regia etching solutions, leaving the non noble Ni–Al rich phase unaffected. Compared to bulk high entropy alloys, the porous structure provides a larger specific surface area and mass transfer channel for the OER. Additionally, the synergetic chemical effects of the high entropy alloy enhance the intrinsic reactivity of the electrode towards the OER. The porous Ni–Al rich phase HEA electrocatalysts exhibit a low OER overpotential of only 240 mV at 10 mA cm−2 and a Tafel slope of 47.1 mV dec−1 in 1.0 M KOH. Density functional theory (DFT) results indicate that the Ni–Al rich phase facilitates the transformation of ∗O to ∗OOH, resulting in superior OER performance compared to the Fe–Cr rich phase. This study introduces a novel strategy for preparing efficient, stable, and noble metal-free electrocatalysts for OER. [Display omitted] • A porous Ni–Al rich phase HEA with ultrahigh catalytic activity is synthesized via a facile CSPD method. • The electrode can stably deliver 10 mA cm−2 at only 240 mV and 47.1 mV dec−1 for OER. • Compared with the rich Fe–Cr phase, the rich Ni–Al phase facilitates the transition from ∗ O to ∗ OOH. [ABSTRACT FROM AUTHOR]

This study investigated the interfacial phase evolution between magnesia refractory and low-density molten steel with different Al contents (0.5 % and 10 %) during the steel-slag reaction. Simulated experiments involving a refractory-steel-slag coupling reaction were conducted under laboratory conditions. The thickness and compositional distribution of the interface layers formed after the refractories were exposed to molten steel and slag were analyzed. The results indicate that, in the absence of slag, a MgAl 2 O 4 layer is formed at the interface between the refractory and molten steel due to the reaction between [Al] and Al 2 O 3 inclusions in the molten steel with the refractory. Upon the addition of slag, CaO in the slag is reduced to Ca and transferred into the molten steel, modifying the solid MgAl 2 O 4 layer at the interface into a primarily liquid CaO·MgO·Al 2 O 3 layer. The liquid interface intensified the erosion of the refractory by the molten steel, resulting in a thickened interface layer. The higher the Al content in the steel, the greater the degree of modification of the CaO·MgO·Al 2 O 3 layer by Ca. The Mg/Ca mass transfer process during the steel-slag reaction was simulated using the FactSage Macros calculation, and the differences in mass transfer between low and high Al contents were compared. The results indicate that under high Al conditions, the supply of Mg/Ca increases significantly. The simulation results were compared with numerous findings in the literature, confirming the accuracy of the simulation. [ABSTRACT FROM AUTHOR]

Ceramic injection molding (CIM) is a near-net-shape technology for the rapid manufacture of complex-shaped small parts. Preparation of thick-walled parts remains a challenge owing to the difficulty in debinding process for green body based on micron and irregular ceramic powders. In this study, spherical metal-ceramic composite powders with different particle sizes were prepared using a wet granulation method. NiFe 2 O 4 -based cermets with a thickness of 20 mm were fabricated using both spherical (SP) and non-spherical (NSP) powders as raw materials. Roles of the powder shapes in catalytic debinding and sintering behaviour were investigated. Compared with that of NSP, green body with SP exhibited improved debinding efficiency, due to the well developed pore channels. A new perspective was proposed to explain the mass transfer mechanism during the debinding process. The adoption of spherical composite powders significantly enhanced the debinding rate without affecting the sintering performance. After sintering, sound cermet parts with uniform microstructure and the highest relative density of 98.62 % were achieved. This provides an important reference for the fabrication of large and thick-walled parts by CIM via controlling the powders. [ABSTRACT FROM AUTHOR]

Ceramics or refractories prepared in the Al 2 O 3 -rich corner of the Al 2 O 3 -MgO-CaO system show excellent high-temperature mechanical properties and chemical stability because of the presence of spinel (MgAl 2 O 4) and calcium hexaluminate (CaAl 12 O 19). However, the densification of these two crystals usually requires high firing temperatures due to their poor sinterability. To address this issue, La 2 O 3 -doped MgAl 2 O 4 -CaAl 4 O 7 -CaAl 12 O 19 refractory composites were designed, and the influence of the doping level on the densification, microstructure, and mechanical properties of the composite was investigated. It was found that the doped La3+ was predominantly dissolved in the CA 6 grains by replacing Ca2+, forming uniform solid solutions regardless of doping concentration. This reaction significantly accelerates ion diffusion and CA 2 grain growth. Besides, it reduces the aspect ratio of CA 6 crystals, weakening the negative effect of the elongated grains on mass transfer and sintering. As a result, the relative density increases from 79.5 % to 95.1 % after sintering at 1600 °C with doping only 0.5 wt% La 2 O 3 into the composite, producing a uniform and dense microstructure with regular angular grains. The above effects result in a significant improvement in flexural strength and fracture toughness (increasing by 61 % and 57 %, respectively). Moreover, the La 2 O 3 -doped refractory composite achieves a decline of the high-temperature creep rate by one order of magnitude at 1600 °C. [ABSTRACT FROM AUTHOR]

This paper examines the effect of rotation on thermal instability under Hele-Shaw cell saturated by Casson nanofluid using both linear and nonlinear ways. The nanofluid model incorporates Brownian and thermophoresis diffusion. While conducting an analysis of nonlinear stability numerically using the truncated Fourier series method, analysis of linear stability is performed analytically using the normal mode methodology. The outcomes are all displayed graphically. The results demonstrate that the rotation has dual effect on Hele-Shaw parameter as well as Casson parameter, for higher value of rotation it has destabilizing effect and it stabilizing  the system for lower values of rotation. Lewis number and concentration Rayleigh number promote the onset of convective motion within the system. On the other hand, rotation stabilize the system. Understanding the behavior of heat and mass transportation, the concentration of nanoparticles and fluid phase, utilize the Nusselt number when Nusselt numbers are assessed as a function of time, it is found that the variation of the rotation, Hele-Shaw and Casson parameter has a major influence on the heat and mass transfer. Both steady and unsteady weakly nonlinear analyses are performed to understand the heat transport in the system. It is concluded that the Casson nanofluid parameter has both stabilizing and destabilizing impact depending upon the rate of rotation and therefore this work can be possibly utilized in both places, where heat removal and heat conservation are required. [ABSTRACT FROM AUTHOR]

It is well‐established that Pt‐based catalysts suffer from the unfavorable linear scaling relationship (LSR) between *OOH and *OH (ΔG(*OOH)=ΔG(*OH)+3.2±0.2 eV) for the oxygen reduction reaction (ORR), resulting in a great challenge to significantly reduced ORR overpotentials. Herein, we propose a universal and feasible strategy of fluorine‐doped carbon supports, which optimize interfacial microenvironment of Pt‐based catalysts and thus significantly enhance their reactive kinetics. The introduction of C−F bonds not only weakens the *OH binding energy, but also stabilizes the *OOH intermediate, resulting in a break of LSR. Furthermore, fluorine‐doped carbon constructs a local super‐hydrophobic interface that facilitates the diffusion of H2O and the mass transfer of O2. Electrochemical tests show that the F‐doped carbon‐supported Pt catalysts exhibit over 2‐fold higher mass activities than those without F modification. More importantly, those catalysts also demonstrate excellent stability in both rotating disk electrode (RDE) and membrane electrode assembly (MEA) tests. This study not only validates the feasibility of tuning the electrocatalytic microenvironment to improve mass transport and to break the scaling relationship, but also provides a universal catalyst design paradigm for other gas‐involving electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

The study developed a two‐dimensional nonisothermal two‐phase flow model and investigated the gas–liquid phase distribution and temperature variations in a proton exchange membrane (PEM) electrolytic cell under microgravity conditions at different inlet flow rates. The impact of microgravity and terrestrial conditions on water electrolytic cells was directly compared. The results indicate that the water electrolytic cell demonstrates effective operation only when the voltage exceeds 1.7 V in a microgravity environment. Furthermore, an increase in inlet flow rate is conducive to electrochemical reactions, resulting in higher average hydrogen concentration, average hydrogen flow rate, and average current density. Under microgravity conditions, the absence of gravity results in lower average hydrogen concentration, flow rate, and current density compared to terrestrial conditions. Furthermore, an increase in inlet flow rate leads to a greater disparity in the performance of the electrolytic cell between microgravity and terrestrial conditions. [ABSTRACT FROM AUTHOR]

Electrolyte additive engineering is a feasible protocol in improving Zn anode stability. Typical additive designs center on the regulation of Zn deposition; nevertheless, versatile additives are urgently requested to comprehensively manage the surface landscape, interface physicochemistry, and by‐product elimination. Here, a straightforward strategy is presented to meet such needs employing an environmentally‐friendly chelator, hydroxyethyl‐ethylenediaminetriacetate acid (HEDTA), as an additive for ZnSO4 electrolyte. Throughout theoretical computations and experimental investigations, it is demonstrated that protons released from the gradual ionization of HEDTA during rest periods aid in the mild engraving of the Zn surface. Both the amino and carboxyl groups of HEDTA⁻ can be protonated, which effectively buffers the interfacial pH value in the entire battery lifespan and eliminates the formation of by‐products. The HEDTA− anions can also adsorb onto the Zn surface, helping facilitate Zn2⁺ mass transfer and accelerate the desolvation process. Benefiting from the synchronous modulation of surface topography and interfacial physicochemistry, the assembled half cells affording HEDTA additive maintain a durable operation of up to 8821 cycles at 5.0 mA cm−2/1.0 mAh cm−2. Additionally, symmetric cells manifest stable cycling for over 4600 h at 0.5 mA cm−2/0.25 mAh cm−2. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Cu‐catalyzed electrochemical CO2 reduction reaction (CO2RR) and CO reduction reaction (CORR) are of great interest due to their potential to produce carbon‐neutral and value‐added multicarbon (C2+) chemicals. In practice, CO2RR and CORR are typically operated at industrially relevant current densities, making the process exothermal. Although the increased operation temperature is known to affect the performance of CO2RR and CORR, the relationship between temperatures and kinetic parameters was not clearly elaborated, particularly in zero‐gap reactors. In this study, we detail the effect of the temperature on Cu‐catalyzed CO2RR and CORR. Our electrochemical and operando spectroscopic studies show that high temperatures increase the activity of CO2RR to CO and CORR to C2H4 by enhancing the mass transfer of CO2 and CO. As the rates of these two processes are highly influenced by reactant diffusion, elevating the operating temperature results in high local CO2 and CO availability to accelerate product formation. Consequently, the *CO coverage in both cases increases at higher temperatures. However, under CO2RR conditions, *CO desorption is more favorable than carbon‐carbon (C—C) coupling thermodynamically at high temperatures, causing the reduction in the Faradaic efficiency (FE) of C2H4. In CORR, the high‐temperature‐augmented CO diffusion overcomes the unfavorable adsorption thermodynamics, increasing the probability of C—C coupling. [ABSTRACT FROM AUTHOR]

Zeolite honeycomb monoliths (ZHMs) as key adsorbents or catalysts are widely applied in industries, for which, however, the popularization is limited by its low production efficiency due to the long and careful drying process of the fragile ZHMs green body. Here we address this challenge by developing a microwave drying strategy coupled with convective air and steam. The individual microwave, microwave-air, and microwave-air-steam drying characteristics on the honeycomb and slab monoliths of 13X zeolite were systematically studied, and the drying quality-microwave power/air temperature/humidity relationship was correlated. The results showed that microwave achieves rapid dehydration of ZHMs, eliminating 29.94 % relative mass of water within only 660 s. However, the uncontrollable microwave adsorbing inhomogeneity and thermal accumulation over the hydrophilic ZHM resulted in overburning, cracking and deformation issues. Introducing convective air at room temperature eliminates overburning and cracking phenomena, and after coupled with 110 g/m3 steam, the irregular deformation of ZHMs was further mitigated (shrinkage rate reduced from 2.10 % to 1.11 %) with even increased drying efficiency by 4.47 %. The advantageous mechanism of microwave-air-steam coupling drying was revealed as the combined effect of the heat and mass transfer through the honeycomb hole enhanced by convective air and the heating and dehydration homogeneity improved by uniform microwave absorbing on surface-condensable steam. The efficacy of the optimized drying strategy was demonstrated by significantly shortened time for scale-up production of 1 m3 ZHMs from nearly 1 month to 2 days. This work affords new insights for improving production efficiency of high-quality ZHMs and presents microwave-air-steam drying process as a platform to advancing structured material preparation. [ABSTRACT FROM AUTHOR]

This work presents the successful manufacture and characterization of bespoke carbon adsorbent microstructures such as tessellated (TES) or serpentine spiral grooved (SSG) by using 3D direct light printing. This is the first time stereolithographic printing has been used to exert precise control over specific micromixer designs to quantify the impact of channel structure on the removal of n‐butane. Activated microstructures achieved nitrogen Brunauer Emmett Teller (BET) surface areas up to 1600 m2 g−1 while maintaining uniform channel geometries. When tested with 1000 ppm n‐butane at 1 L min−1, the microstructures exceeded the equilibrium loading of commercial carbon‐packed beds by over 40%. Dynamic adsorption breakthrough testing using a constant Reynolds number (Re 80) shows that complex micromixer designs surpassed simpler geometries, with the SSG geometry achieving a 41% longer breakthrough time. Shorter mass transfer zones were observed in all the complex geometries, suggesting superior kinetics and carbon structure utilization as a result of the micromixer‐based etched grooves and interlinked channels. Furthermore, pressure drop testing demonstrates that all microstructures had half the pressure drop of commercial carbon‐packed beds. This study shows the power of leveraging 3D printing to produce optimized microstructures, providing a glimpse into the future of high‐performance gas separation. [ABSTRACT FROM AUTHOR]

To enhance the power-to-hydrogen (P2H) efficiency and multiple energy utilization efficiency of the hydrogen-electric integrated energy system (HE-IES), an optimal operation framework considering the P2H factor is proposed. First, the proton exchange membrane electrolytic cells model which considers mass transfer characteristics is established. Efficient hydrogen production operating parameters are obtained through simulation to maximize the P2H efficiency. Second, the HE-IES is established, including the hydrogen flow system, wind power (WP), energy storage systems, gas boiler, combined heat and power and methanation unit. Based on the characteristics of the devices and efficient hydrogen operating parameters, the optimal operation framework considering the P2H efficiency factor is proposed. To realize the low economic operating costs and maximize the utilization of WP, a multi-objective function based on fuzzy membership function solving is applied. Finally, the case studies show that the proposed operation framework reduces the economic operation cost by 28.29% and improves the WP utilization rate by 31.9%. [ABSTRACT FROM AUTHOR]

Maintaining a consistently high current density growth rate in the hydrogen evolution reaction is highly challenging because the limited mass transfer rate at the electrode/electrolyte interface will make the adsorption reaction as the rate‐determining step associated with a low hydrogen coverage, exhibiting a Tafel slope >120 mV dec–1. Therefore, maximizing the current density range in which the desorption reaction is the rate‐determining step, can significantly reduce the overpotential. Herein, a surface sulfur decoration strategy is presented to modify the molybdenum carbide electrocatalyst and achieve coordinated adsorption/desorption kinetics, leading to a dominant Volmer–Heyrovsky mechanism across a wide range of current densities. Both experimental and theoretical results validate the surface charge redistribution induced by sulfur decoration, which subtly optimizes the Gibbs free energy of hydrogen adsorption and enhances the in‐plane polarization field. As a result, the as‐obtained surface sulfur‐decorated molybdenum carbide electrocatalyst exhibits coordinated adsorption/desorption kinetics and efficient hydrogen delivery, ultimately surpassing the commercial Pt/C electrocatalyst for high‐efficiency hydrogen evolution. [ABSTRACT FROM AUTHOR]

Achieving ampere‐hour‐scale capacities in pouch‐type zinc–air batteries (ZABs) requires optimizing key factors, such as preventing inactive ZnO dendrite formation on zinc anodes and enhancing catalytic activity with efficient gas diffusion in the air cathode. Here, a pioneering flexible, large‐area, ampere‐hour‐scale quasi‐solid‐state ZAB is introduced, addressing these challenges through a novel preactivation strategy combined with a layered assembly approach. This method employs mass‐producible fibrous carbon textiles to form flexible fabrics that separate functions within multi‐stacked layers. Preactivated carbon fabric layers, independently functionalized and easily reassembled, enhance scalability and manufacturability. A bilayer catalytic air electrode, incorporating hydrophilic NiFe hydroxide and hydrophobic FeNC regions, ensures efficient charge and mass transfer, significantly boosting catalytic activity. To prevent dendrite formation on the zinc anode, a zincophilic copper interlayer is implemented. This configuration supports rapid, stable charge–discharge cycles at a high current density of 20 mA cm⁻2. The large‐area stacked bipolar structure pouch cells, exceeding 36 cm2, achieve a discharge capacity of up to 2500 mAh, maintaining high cycle stability through discharge–charge cycles with 200 mAh per cycle. This approach significantly enhances the scalability, manufacturability, and production potential of ultrahigh‐capacity wearable ZABs, making them practical for widespread application in various portable and flexible devices. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Cu‐catalyzed electrochemical CO2 reduction reaction (CO2RR) and CO reduction reaction (CORR) are of great interest due to their potential to produce carbon‐neutral and value‐added multicarbon (C2+) chemicals. In practice, CO2RR and CORR are typically operated at industrially relevant current densities, making the process exothermal. Although the increased operation temperature is known to affect the performance of CO2RR and CORR, the relationship between temperatures and kinetic parameters was not clearly elaborated, particularly in zero‐gap reactors. In this study, we detail the effect of the temperature on Cu‐catalyzed CO2RR and CORR. Our electrochemical and operando spectroscopic studies show that high temperatures increase the activity of CO2RR to CO and CORR to C2H4 by enhancing the mass transfer of CO2 and CO. As the rates of these two processes are highly influenced by reactant diffusion, elevating the operating temperature results in high local CO2 and CO availability to accelerate product formation. Consequently, the *CO coverage in both cases increases at higher temperatures. However, under CO2RR conditions, *CO desorption is more favorable than carbon‐carbon (C—C) coupling thermodynamically at high temperatures, causing the reduction in the Faradaic efficiency (FE) of C2H4. In CORR, the high‐temperature‐augmented CO diffusion overcomes the unfavorable adsorption thermodynamics, increasing the probability of C—C coupling. [ABSTRACT FROM AUTHOR]

Nitrocellulose (NC) finds widespread use in propellants and launchers. Nanoscale modification can effectively enhance its combustion performance by shortening the mass and heat transfer distance. However, it also presents greater safety challenges for storage and application. To further investigate the thermal safety characteristics of nanoscale NC, this study explores the impact of additives on nanoscale NC. Nanoscale NC was prepared via electrospinning, and the samples were characterized using focused ion beam scanning electron microscopy to examine the influence of precursor concentration and stabilizer on sample morphology, leading to the formulation determination. Samples incorporating triphenylamine and lithium carbonate (Li2CO3) were fabricated using both electrospinning and traditional mechanical mixing techniques. Following preparation, fourier transform infrared spectroscopy, the methyl violet test, and thermogravimetry–differential scanning calorimetry were performed on six samples, each prepared using different methods and additives. These analyses aimed to investigate the thermal decomposition characteristics of the samples under varying heating rates. The study also compared the impact of nanoscale modification on the thermal performance of composite nitrocellulose. Various model-free methods were employed to calculate the relationship between activation energy and conversion rate and to analyze alterations in activation energy. Considering the thermal decomposition characteristic parameters, the study delved into the stabilizing effect of typical stabilizers in nanocomposite fibers. This research is instrumental in guiding preparation process optimization, promoting the application of NC-stabilizer mixtures, and providing valuable references for the preparation and thermal stability investigations of similar nanomaterials. [ABSTRACT FROM AUTHOR]

Cross-diffusion effects are essential in industry because they can improve process efficiency, optimize product development, improve environmental sustainability, and drive technological advancements. The effects of cross-diffusion, aligned magnetization, and radiation are considered and adequately reported on the micropolar fluid boundary layer. The momentum, energy, and species reaction models are utilized to quantitatively represent the flow equations containing the thermophysical parameters at an aligned angle. The described fluid models are transformed into ordinary systems of derivatives. The solution to the resulting equations is determined via Fehlberg Runge–Kutta. The impacts of related terms are presented on various plots. The investigation revealed that the aligned angle strengthens magnetic field parameters, which can also lower the flow. For injection cases, microrotation has a parabolic distribution. An inclined value of radiation term contributed to improving the temperature profile. Temperature and concentration profiles rise and decrease with the Soret number, affecting heat, and species transport rates. The porosity and the thermal buoyancy parameter exhibit conflicting behaviors for both the coefficient of plate drag and the couple stress. [ABSTRACT FROM AUTHOR]

Binder plays a crucial role in constructing high‐performance electrodes for water electrolysis. While most research has been focused on advancing electrocatalysts, the application of binders in electrode design has yet to be fully explored. Herein, the in situ incorporation of polytetrafluoroethylene (PTFE) as a multifunctional binder, which increases electrochemical active sites, enhances mass transfer, and strengthens the mechanical and chemical robustness of oxygen evolution reaction (OER) electrodes, is reported. The NiFe‐LDH@PTFE/NF electrode prepared by co‐deposition of PTFE with NiFe‐layered double hydroxide onto nickel foam demonstrates exceptional long‐term stability with a minimal potential decay rate of 0.034 mV h−1 at 500 mA cm−2 for 1000 h. The alkaline water electrolyzer utilizing NiFe‐LDH@PTFE/NF requires only 1.584 V at 500 mA cm−2 and sustains high energy efficiency over 1000 h under industrial operating conditions. This work opens a new path for stabilizing active sites to obtain durable electrodes for OER as well as other electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Practical Application The aim of this study was to investigate the effect of different ultrasound treatment (UT) conditions (Control, UT‐150, UT‐300, UT‐450, Vacuum‐UT‐150, Vacuum‐UT‐300, Vacuum‐UT‐450) on the brining kinetics and meat quality of chicken breast. The results showed that vacuum‐ultrasonic‐assisted treatment greatly accelerated the transfer of moisture and NaCl, and the highest yield was obtained by ultrasonic power of 450 W. The mass transfer kinetics (k1 and k2) were significantly related to vacuum pretreatment and ultrasonic power. The values of k1 for total and moisture weight changes decreased with the increase of ultrasonic power, whereas the values of k2 increased with vacuum pretreatment. The application of ultrasound treatment with vacuum improved the NaCl effective diffusion coefficients (De) from 1.189 × 10−9 to 1.308–1.449 × 10−9 m2/s, and the highest De was found with Vacuum‐UT‐450. The treatment of ultrasound and vacuum can reduce shear force and enhance the water‐holding capacity (WHC). According to the analysis of water distribution, vacuum and ultrasound could decrease the T23 values, indicating that the mobility of water decreased. The result of microscopic observation further supported that the disruption of myofibrils was related to the tenderness and WHC changes, which was caused by vacuum and ultrasound treatment. Thus, Vacuum‐UT brining could be employed as an emerging technology for improving the efficiency of brining and meat quality of other meat.Vacuum‐ultrasonic‐assisted static brine is an effective and feasible treatment to replace tumbling treatment for maintaining the integrity of the muscle bundles and accelerating the brining rate. [ABSTRACT FROM AUTHOR]

Utilizing electrons directly offers significant potential for advancing organic synthesis by facilitating novel reactivity and enhancing selectivity under mild conditions. As a result, an increasing number of organic chemists are exploring electrosynthesis. However, the efficacy of electrochemical transformations depends critically on the design of the electrochemical cell. Batch cells often suffer from limitations such as large inter-electrode distances and poor mass transfer, making flow cells a promising alternative. Implementing flow cells, however, requires a foundational understanding of microreactor technology. In this review, we briefly outline the applications of flow electrosynthesis before providing a comprehensive examination of existing flow reactor technologies. Our goal is to equip organic chemists with the insights needed to tailor their electrochemical flow cells to meet specific reactivity requirements effectively. We also highlight the application of reactor designs in scaling up electrochemical processes and integrating high-throughput experimentation and automation. These advancements not only enhance the potential of flow electrosynthesis for the synthetic community but also hold promise for both academia and industry. [ABSTRACT FROM AUTHOR]

The maturation of CO2 electrolysis to CO technology has rendered a cascade catalysis scheme, utilizing CO reduction as a media step, a promising strategy to produce high‐value C2+ fuel. However, the current catalysts employed in CO electroreduction (ECORR) face severe hydrogen evolution reactions at high current densities. Herein, a 2D porous Cu3N (2D‐P‐Cu3N) catalyst is reported with outstanding ECORR performance prepared by a two‐step pyrolysis strategy. This strategy mainly relies on the sequential annealing of the Cu2(OH)2CO3 precursors in an oxidation and reduction atmosphere, which can not only convert it into high‐purity Cu3N, but also endow it with an abundant hierarchical pores structure. The pores can significantly improve the in‐plane conductivity and mass transfer capacity of Cu3N, enabling a C2+ faradaic efficiency exceeding 90% at a current density of 0.6 A cm−2. Even at an ampere grade current density of 1 A cm−2, it maintains an impressive 87% selectivity, surpassing most of the reported Cu‐based catalysts. In‐situ Raman spectroscopy confirms that 2D‐P‐Cu3N exhibits high coverage and adsorption of CO intermediates, thus enhancing C‐C coupling and promoting the generation of C2+ products. This discovery opens further exploration of catalysts for selective CORR to C2+ products. [ABSTRACT FROM AUTHOR]

Dinuclear metal synergistic catalysis (DMSC) has been proved an effective approach to enhance catalytic efficiency in photocatalytic CO2 reduction reaction, while it remains challenge to design dinuclear metal complexes that can show DMSC effect. The main reason is that the influence of the microenvironment around dinuclear metal centres on catalytic activity has not been well recognized and revealed. Herein, we report a dinuclear cobalt complex featuring a planar structure, which displays outstanding catalytic efficiency for photochemical CO2‐to‐CO conversion. The turnover number (TON) and turnover frequency (TOF) values reach as high as 14457 and 0.40 s−1 respectively, 8.6 times higher than those of the corresponding mononuclear cobalt complex. Control experiments and theoretical calculations revealed that the enhanced catalytic efficiency of the dinuclear cobalt complex is due to the indirect DMSC effect between two CoII ions, energetically feasible one step two‐electron transfer process by Co2I,I intermediate to afford Co2II,II(CO22−) intermediate and fast mass transfer closely related with the planar structure. [ABSTRACT FROM AUTHOR]

This review explores the Neapolitan pizza baking process in a traditional wood‐fired oven, employing visual color analysis and IR thermal scanning to detail heat exchange mechanisms. During cooking, the oven floor temperature in the pizza area decreased proportionally to the pizza's mass, whereas the free area maintained a constant temperature of 439 ± 3°C. An IR thermal camera indicated that the oven dome temperature reached approximately 480°C with a weak flame and 500°C with a strong flame. The pizza's bottom achieved a maximum temperature of 100 ± 9°C, facilitated by the Pizzaiolo's skill in lifting and rotating the pizza for uniform cooking. Top temperatures varied: up to 180°C for white pizza and 84°C and 67°C for tomato and Margherita pizzas, respectively. IRIS electronic eye analysis revealed more browning and blackening on the pizza's top compared to its bottom, with peaks of about 26% and 8% for white pizza, respectively. Rapid baking is pivotal in Neapolitan pizza‐making, necessitating precise heat and mass transfer management to influence sensory attributes. European Commission Regulation No. 97/2010 mandates wood‐fired ovens for true Neapolitan pizza, but environmental concerns prompted the Associazione Verace Pizza Napoletana to certify gas or electric ovens when wood‐fired ovens are impractical. Operating costs vary: liquefied petroleum gas ovens are the costliest, with costs ranging from €5.38 to €6.19/h, whereas natural gas and electric ovens have operating costs between €2.70 and €4.10/h. At €0.15/kg, firewood is the most economical, supporting traditionalist views. However, natural gas and electric ovens present competitive costs under stringent antipollution laws, making them viable alternatives. [ABSTRACT FROM AUTHOR]

With the recent developments of composite polymer materials, the usage of synthetic materials in interior furnishing has rapidly increased. Polymeric foams such as polyurethane (PU) and polyethylene (PE) are widely applied as upholstered furniture and wall insulations. Nevertheless, the occurrence of fire in a confined environment surrounded by combustible polymeric materials can lead to disastrous consequences. This is because the toxic emission of polymers, specifically carbon monoxide (CO), is responsible for most deaths and injuries in building fires. Thus, it is essential to gain an in-depth understanding of material flammability and gaseous product emissions, as well as the correlation against various radiant heat fluxes, temperatures and ventilation conditions. In this study, cone calorimeter with Fourier Transform Infrared Spectroscopy (FT-IR) was performed on PU, PE and Ethylene–vinyl acetate (EVA) foam to (i) characterise the critical combustion performances; and (ii) obtain real-time emission profiles of asphyxiant gases such as hydrogen cyanide (HCN), formaldehyde (HCHO), and acrolein, under flaming conditions. Furthermore, a fire dynamics simulator (FDS) model was constructed to study the burning characteristics of the selected materials numerically. Furthermore, the in-depth heat and mass transfer involved during the various development stages of the fire are studied via simulation results. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysis plays a pivotal role in the current chemical and energy vectors production. Notably, to fully utilize the intrinsic activity and selectivity of a catalyst, the chemical reactor has to be designed and operated optimally to achieve enhanced heat/mass transfer, well-defined contact time of reactants, uniform flow pattern, and high permeability. Structured catalysts are a promising strategy to overcome the major drawbacks encountered in the traditional packed-bed reactor technology due to the improved hydrodynamics in combination with enhanced heat/mass transfer. Newly emerged fiber/foam-substrates, with an entirely open 3D network structure, bring distinct advantages over the honeycomb and micro-channel contacting methods, including free radial diffusion, eddy-mixing driven heat/mass transfer, large area-to-volume ratio, and high contacting efficiency. However, how to place the nanocatalysts onto the fiber/foam-substrates is a challenging problem because the commercial washcoating method has great limitations such as the nonuniformity and easy exfoliation of coatings. This review discusses the newly developed non-dip-coating methods for the fiber/foam-structured catalysts and their promising applications in the strongly exo-/endo-thermic and/or high throughput reaction processes. [ABSTRACT FROM AUTHOR]

This work considers the isothermal process of incompressible viscous fluid filtration in an oil-saturated, fractured-porous reservoir. A study of the pressure and water saturation distribution process is carried out for a case in which a production well is put into operation. For this problem, i.e., a mathematical model in a two-dimensional formulation, a numerical method and a parallel algorithm are proposed. The mathematical model of two-phase filtration is written in accordance with the classical laws of continuum mechanics and Darcy's law and also includes a function of fluid exchange between low-permeability pores and high-permeability natural fractures within the framework of the Warren–Root model. The numerical solution is based on the finite-difference method and a splitting scheme of physical processes and spatial coordinates. For a split system with respect to piezoconductivity, an implicit finite-difference scheme with fixed saturations is constructed, and with respect to saturation transfer, explicit and implicit difference schemes are constructed. For parallel implementation of the developed numerical approach, a method based on geometric parallelism is selected. Testing of the developed method is performed using the example of calculating liquid mass transfer for a wide range of parameters. To verify the model, the obtained calculated pressure curves are compared with field data recorded by a deep-well measuring device. The results allow for estimation of the distribution of reservoir pressure and water saturation depending on the permeability of the fracture set and the pore part. The obtained results allow for monitoring of well operations, reducing unexpected accident risks and optimizing the development system in order to increase oil production in fractured-porous reservoirs. Computational experiments confirm the efficiency of the developed numerical algorithm and its parallel implementation. [ABSTRACT FROM AUTHOR]

This numerical study investigates the impact of the reaction temperature, molar ratio of CH4:CO2, and catalyst porosity (εp) on the H2 yield and H2 selectivity during biogas dry reforming over a Ni/Cr catalyst. Using COMSOL Multiphysics, we conducted detailed simulations to elucidate the underlying reaction characteristics. Our findings reveal that increasing εp from 0.1 to 0.95 significantly provides a 5 times increase in H2 production and a 2.3% increase in H2 selectivity while simultaneously reducing CO selectivity by 2.3%. This effect is attributed to the improved mass transfer within the catalyst bed, leading to more efficient reactant conversion and product formation. Additionally, we observed a strong correlation between higher reaction temperatures and increased H2 yield and H2 selectivity. By optimizing these operational parameters, our results suggest that Ni/Cr catalysts can be effectively employed for the sustainable production of H2 from biogas. [ABSTRACT FROM AUTHOR]

The Al alloy melting behavior and interfacial reactions during the steelmaking process of high-Al automotive steel were investigated in this study. The total dissolution time of Al bars (20 × 20 × 80 mm) in molten steel was quite short, decreasing from 21.4 s to 10.0 s with an increase in bath temperature from 1580 to 1620 °C. The Al alloy melting process at the molten steel temperature of 1600 °C included the formation of a solidified steel layer, the latter's rapid melting, and Al alloy normal melting, while at 1600 °C, the process included a second increase in the thickness of the solidified layer. Because steel elements such as [Fe], [C], [O], and [N] could diffuse during the whole Al alloy melting process, an Fe (Al)-FeAl-FeAl2-Fe2Al5-Al diffusion layer along the direction of the Al-rich matrix could be found at the Fe–Al interface. Moreover, FexO, Al2O3, and unstable AlN inclusions could be observed in the FeAl layer. This study also investigated how to reduce the number of these easily formed inclusions. Decreasing the pre-heating process time and dissolved oxygen content could be useful in decreasing FexO and Al2O3 inclusion formation. Some small-sized AlN inclusions formed in the center of the Al bars where they could not come into contact with the molten steel directly during the melting process; even for the immersion time of only 1 second, these inclusions were not stable in molten steel at the refining temperature and disappeared during the melting process. [ABSTRACT FROM AUTHOR]

This contribution focuses on the spatial‐temporal behavior and reactive pathways of O3 produced by a surface air microdischarge in the gas and liquid phase using ultraviolet absorption spectroscopy. The findings demonstrate that mode transition from ozone to nitrogen oxide over time is observed at a constant input power higher than ~0.60 W/cm2. Due to the long‐lived characteristic and ionic wind, the perpendicular distribution of O3 is almost uniform. The maximum penetration depth is around 5 mm, and the gas–liquid mass transfer efficiency is approximately 0.4‱ at a depth of 1 mm, when the treatment time is 10 min. The mass transfer of O3 between gas and liquid phases is dominated by the liquid convention induced by ionic wind. [ABSTRACT FROM AUTHOR]

Obtaining snacks from the drying of surplus vegetables is an alternative to reduce waste. A combination of pulsed electric field (PEF) pretreatments and ultrasonic-assisted (US) drying could significantly enhance the process, as this is the aim of this study. PEF pretreatments of yellow turnip significantly affected the cell disintegration index (CDI) and the water holding capacity (WHC): the more intense the PEF treatment, the greater the CDI and the lower the WHC. Both parameters, CDI and WHC, showed a high degree of correlation which indicated that WHC can be an alternative index to CDI to assess PEF effects on food matrices. Regarding yellow turnip drying (40 °C), PEF pretreatments (CDI 0.25 and 0.75) and US application (20.5 kW/m3) significantly accelerated the operation, but it was the combination of both technologies that provided the shortest process (CDI 0.75). PEF could generate changes in the food matrix which enhance the US effects on mass transfer. [ABSTRACT FROM AUTHOR]

Dryers are designed once but then operate for many years, and it is important to have systematic methods to solve problems when they arise. Kemp and Gardiner proposed a systematic methodology in 2001, based on categorization of problems into five main types and a divergent-convergent algorithm to identify both root causes and potential solutions. This approach to troubleshooting has proved successful for dryers in a range of industries. This article reviews the experience gained, some resulting improvements, and overlap and synergy with other investigation methods such as Lean Six Sigma techniques. An extensive range of case studies is given, illustrating the successful application of the methodology to many different situations and dryer types. The broad approach has remained the same but various points of detail have been added. Appropriate theoretical models can give useful insights, often using quite simple methods such as heat and mass balances and drying times estimated with first-order kinetics. The insights can solve other drying-related problems such as caking in storage. The methods can also be used for process improvement, debottlenecking, and enhanced product quality. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the crevice corrosion behavior of carbon steel in neutral/alkaline environments utilizing a transient multi-physics field model. Design/methodology/approach: The crevice corrosion of carbon steel with different solution pH and crevice width was modeled, incorporating mass transfer, homogeneous phase and localized electrochemical reactions. The extent of crevice corrosion was evaluated by the geometric deformation of the model mesh. The hydro-chemical state inside the crevice was discussed through the Cl− concentration and potential distribution of the solution. Findings: Results revealed that the formation of pitting corrosion near the crevice mouth was accelerated in a neutral solution. When pH = 8 and pH = 9, the carbon steel matrix was dissolved and the Cl− content within the solution was significantly reduced due to the higher concentration of hydroxide ions (OH−). Originality/value: The crevice corrosion behavior of carbon steel in neutral/alkaline environments is closely associated with solution pH rather than the crevice width. The inhibition of crevice corrosion in alkaline environments was proved by finite element simulation. These findings provide valuable insights that can be applied in engineering applications to prevent and mitigate crevice corrosion in neutral/alkaline environments. [ABSTRACT FROM AUTHOR]

This study examines the influence of thermal radiation and heat source/sink of the tangent hyperbolic fluid on EMHD boundary layer flow through stretching sheets. Motile gyrotactic microorganism is considered in the fluid flow and the flow is analyzed with the impact of thermal radiation, heat source/sink, and electromagnetohydrodynamic. By utilizing the proper similarity transformations, partial differential systems are converted to ordinary differential systems. The Runge–Kutta fifth‐order method with shooting technique is used in the converted systems to solve numerically. Velocity, temperature, concentration, and microorganism density profile are discussed and represented graphically. The numerical values of drag force rate, heat transfer rate, mass transfer rate, and density of motile microorganisms are specified, compared, and results enhancement in heat transfer rate as 64.31% by radiation parameter, mass transfer rate as 97.28% by heat source/sink parameter and microorganism density rate as 28.33% by Peclet number, respectively. The buoyancy parameter diminishes the drag force by 30.39%. The multiple and quadratic regression coefficient for adjusted R2${R}^2$, multiple R2${R}^2$, residual standard error, F‐statistic, and p‐value is estimated for skin friction, Nusselt number, Sherwood number, and density of microorganism. It has significant applications which are widely used to transport biological material in bio‐microfluidics, enhance heat dissipation in high‐performance electronics, thermal management systems on spacecraft and satellites, and solar energy systems. [ABSTRACT FROM AUTHOR]

Pumpkin seeds swagger a wealthy vitamin and mineral composition. They contain vitamins (A, B, C, K, D, E), minerals (calcium, selenium, zinc, magnesium, copper, potassium, press, manganese and phosphorus), a few amino acids such as glutamic, linolenic and arginine, and greasy plant acids. The Peclet number includes the peripheral rotation speed of the RTS condenser tube. In our case, the Peclet number reflects how the heat transfer to the grain layer due to convection, when the RTS capacitor rotates, relates to the heat transfer due to the thermal conductivity of the grain layer. Thus, in the first drying period, the determining factors for mass transfer will be the conditions at the phase boundary – the mode of air movement outside the grain, the area of the grain, the surface temperature of the RTS condenser. In total, pumpkin seeds contain 12 essential and eight nonessential amino acids. [ABSTRACT FROM AUTHOR]

The modification of petroleum resin (PR) by catalytic hydrogenation is an upgrading technology for producing high-value-added hydrogenated petroleum resin (HPR) from of pyrolysis petroleum by-product. This research employed alumina supports with different pore size distributions to prepare supported Mo-Ni type catalysts and investigated their catalytic hydrogenation performance on C9 petroleum resin. Catalysts prepared with bimodal pore alumina (BPA) supports effectively overcome the limitations of internal diffusion and increase the quantity of active sites, thus increasing the catalytic activity for hydrogenation. The experimental results demonstrated that MoNi/BPA achieved a hydrogenation degree of 99.94% for HC9PR, with the hydrogenated product having a Pt–Co colour of 2.37 Hazen. After 140 h of reaction, the hydrogenation degree of HC9PR remained at 96.51%, and the Pt–Co colour value was lower than 40 Hazen. This investigation confirms that solving the mass transfer issues of petroleum resin molecules in the pores of supported catalysts is key to designing efficient hydrogenation catalysts for petroleum resin. [ABSTRACT FROM AUTHOR]

This study investigates the fluid flow, heat, and mass transfer phenomena within a vertical channel containing two immiscible fluids, with a particular focus on slip effects. These effects include no slip, velocity slip, thermal slip, and multiple slips, each analyzed with appropriate boundary conditions. The study thoroughly examines key characteristics, such as variations in thermal conductivity and viscosity. Using a sixth‐order Runge–Kutta numerical method implemented using Mathematica, the study achieves precise solutions for complex scenarios. The detailed results show how the various slip mechanisms and relevant parameters interact with each other in complex ways. These findings are useful for both theoretical understanding and application in real‐life engineering situations. This study also gives important information about how fluid flow, heat transfer, and mass transfer change under different slip effects. It looks at these effects and shows how they change visually. It also carefully calculates and analyzes engineering parameters like the Nusselt number, shear stress, and Sherwood number using bar charts, showing how they affect and behave. The study resulted in velocity slip having a minimal impact on temperature, whereas thermal slip resulted in higher temperatures. Both velocity and thermal slip conditions simultaneously result in the lowest temperatures. [ABSTRACT FROM AUTHOR]

The conventional packed bed humidifiers encounter significant drawbacks such as scale formation, spray nozzle clogging, corrosion, and relatively poor effectiveness, which adversely affect their reliability and lifespan, thereby escalating their operational and capital costs. To tackle these issues, bubble column humidifiers have been proposed. The bubble column design ensures maximum air–water interaction, enhancing component effectiveness, while obviating the need for atomizers, thereby decreasing maintenance expenses, and enhancing heat and mass transfer efficiency. Moreover, studies related to a moving streams multi-stage bubble column HDH design are lacking. Therefore, this study aims to provide a theoretical analysis of various configurations of multi-stage moving streams bubble column humidifiers, aiming to bridge the performance knowledge gap between moving stream and nonmoving stream bubble column humidifiers. A mathematical model based on heat and mass transfer was developed and validated against published data. The effect of multistaging, water inlet temperature, air inlet temperature, and inlet relative humidity on the total effectiveness, outlet humidity ratio and outlet air temperature are studied. Results reveal that multistaging is effective in boosting the maximum effectiveness of single stage bubble column humidifier from 27% and 33% to about 94% and 94%, for the parallel and series configurations, respectively. Furthermore, both series and parallel configurations show similar performance with a slightly higher performance for the series arrangement. Additionally, this study discusses the operational and maintenance differences between the parallel and series multi-stage bubble column humidifiers, with the series configuration having a more straightforward operation compared to the parallel arrangement. However, the parallel configuration requires less complicated maintenance in comparison to the series multi-stage configuration. The outcomes of this study are pivotal to understanding the optimum operating conditions of the humidifier for its possible integration with the dehumidifier. Consequently, an improved humidification dehumidification (HDH) desalination system can be attained. [ABSTRACT FROM AUTHOR]

The design integration of absorption and adsorption cooling systems is a recently emerging research field in which the inherent advantages of both these systems are intended to be combined so as to maximize system performance. However, a vast majority of the conventional integration approaches reported in the literature still suffer from the following drawbacks: (a) the inability to provide a continuous cooling effect of the integrated design during the switching period of the adsorption component, (b) the lack of incorporation of the mass/heat recovery cycles and its subsequent effects upon the integrated performance, and (c) the lack of functional dependence of all thermodynamic variables including heat capacities and adsorption enthalpy upon operational parameters such as temperature and pressure. This study presents the first attempt of a numerically validated performance prediction of such an integrated system with parallel functionality to facilitate a continuous cooling operation. An empirical model of mass recovery cycle has been formulated for the very first time which adequately describes the sorption dynamics during mass transfer. All thermodynamic variables have been expressed as functions of operational parameters during the cooling cycle. For a mean driving temperature predicted to be as low as 38 °C and a mean cycle time of 11.82 min, the proposed integrated design has been predicted to yield a cycle-averaged specific cooling power of 48.93 W kg−1 and a minimum achievable coefficient of performance of 0.74 compared to the corresponding values of 27.64 W kg−1 and 0.57 for the benchmark stand-alone silica gel/water adsorption chiller. [ABSTRACT FROM AUTHOR]