Post-combustion chemical absorption remains the most mature technology for large-scale CO2 capture; however, its widespread application is limited by the combined effects of regeneration energy demand, gas–liquid mass transfer limitations, and scale-up challenges in practical reactors. These challenges are closely related to the coupling between bubble-scale hydrodynamics, interfacial transport, reaction kinetics, and reactor-scale hydrodynamics, which remains insufficiently understood. This review examines CO2 absorption from the perspective of gas–liquid multiphase process intensification, focusing on bubble dispersion systems. We discuss the fundamentals of interfacial mass transfer and the physicochemical properties of both conventional and emerging absorbents, then turn to bubble dynamics from single-bubble rise and shrinkage to swarm behavior and micro-/nanobubble generation, and their consequences for interfacial area and contact efficiency. Reactor-level intensification approaches, including modified internals, external-field coupling, and nanoparticle or surfactant additives, are assessed in terms of both mass transfer enhancement and energy consumption. By linking microscale bubble behavior with reactor-scale performance, this review clarifies the effects of multiphase transport processes on the energy efficiency and scalability of CO2 absorption systems, and provides insight for the design and optimization of low-energy and industrially scalable carbon capture technologies.

The effects of microgel particles as interface stabilisers on the droplet formation process in a T-junction microchannel were experimentally investigated. Aqueous solutions of microgel particles (similar to 830 nm) at concentrations of 0%wt, 0.17 %wt, 0.34 %wt, 0.68 %wt, and a silicon oil (viscosity of 4.6 mPa.s) were used as the dispersed and the continuous phases, respectively. From high speed imaging four droplet generation patterns were identified, namely squeezing, dripping, jetting and threading, and droplet formation pattern maps were built. It was found that the addition of the microgels did not affect the transition boundaries between the different patterns. However, the droplet formation times in the presence of microgels were longer compared to the pure systems, resulting in larger droplet sizes. For microgel-laden systems, a change in microgel concentration only affected the droplet sizes in the jetting regime but not in the dripping one. Correlations were proposed to predict the droplet size in the dripping and jetting regimes, which included the phase flow rate ratio and the continuous phase capillary number.

Methanol is an attractive liquid hydrogen carrier owing to its high hydrogen density, convenient storage and transport, and its potential for sustainable production from renewable carbon resources. Plasma-assisted methanol decomposition offers a flexible and on-demand pathway for hydrogen generation under near-ambient conditions, avoiding the limitations of conventional thermocatalytic processes. In this work, a liquid-phase plasma discharge system was developed for methanol decomposition, in which plasma-catalyst synergistic effects promote molecular activation, accelerate reactions, and suppress carbon deposition. Systematic evaluation of electrode geometry demonstrates that the needle-needle configuration enhances hydrogen production by 10.3%, achieving a hydrogen flow rate of 685.75 +/- 11.96 mL/min compared with a conventional needle-ring design, owing to its more concentrated and spatially distributed discharge. Further performance improvements are obtained using tungsten-nickel (W-Ni) alloy electrodes, which increase the hydrogen flow rate to 754.98 +/- 15.04 mL/min, effectively mitigate carbon deposition, and maintain a high energy conversion efficiency of 56.72 +/- 0.25%. As a result, the optimized system achieves a specific energy consumption of 1.14 +/- 0.03 kWh/Nm(3) H-2, representing a 10.5% reduction relative to pure tungsten electrodes. These findings underscore the critical roles of plasma-catalyst synergy and electrode material engineering in the development of efficient, durable, and energy-efficient hydrogen production systems from methanol or other liquid fuels.

Electro-dehydration enables efficient demulsification of emulsions, laying a theoretical and technical foundation for addressing the deep dehydration challenge of produced fluids in nanofluid flooding. In this work, molecular dynamics (MD) simulations are conducted to investigate the coalescence dynamics of nanoparticle-laden droplet groups under the coupled rotating electric (RE) and rotating flow (RF) fields. The effects of RE field intensity, RF field frequency, coupling effect of RE and RF fields, and water content on droplet group coalescence are systematically analyzed. The results indicate that under the coupled RE-RF field, increasing RE field intensity exerts no significant enhancement on the migration velocity of droplets toward the wall when CaE ≤ 12.79. In addition, the CaE for the formation of strip-like structures (CaE = 18.41) under the coupled RE-RF field is considerably higher than that under a single RE field (CaE = 4.60). At low RF field frequencies (ωf⁎ = 2, 3), a higher frequency (ωf⁎ = 3) weakens the promotion of the RE field on droplet group coalescence. Upon further increasing the RF field frequency (ωf⁎ ≥ 4), the RE and RF fields exhibit a synergistic effect that jointly facilitates droplet group coalescence. Compared with other field configurations, the coupled RE-RF field more effectively promotes droplet group coalescence, suppresses the formation of strip-like structures, and achieves higher droplet separation efficiency. This study clarifies the microscopic mechanism underlying the enhanced coalescence of nanoparticle-laden droplet groups under the coupled RE-RF field. The findings provide theoretical guidance for the design and optimization of dehydration equipment for produced liquids in nanofluid flooding.

The cone-jet electrospray in whipping instability regime has a very significant and potential interest in microstructures and nano-structures technological fields. In present study, the jet behaviors in whipping instability regime were experimentally studied and the occurrence mechanism of this instability was quantitively analyzed employing ethanol and ethylene glycol as working fluids. The phase chart related to the operating parameters for whipping instability was presented. The straight jet length grows with an increase of the electric Bond number, while the steady section jet length decrease since the shortening of the conical liquid meniscus at high electric Bond number exceeds the increase of the straight jet length. Owing to the acceleration effect originating from tangential electric stress, the straight jet diameter constantly decreases during its movement along the axial direction under a fixed capillary number. The diameter at the end of the straight jet increases with the increase of capillary number for a constant electric Bond number. When the electric ratio exceeds the critical value of 1.0, the electric stress overcomes the surface tension and viscous force, inducing the jet to start lateral bending motion and finally forming helical thin filaments. The critical stress ratio for whipping in the ethanol jet is 1.02, while the critical value for the ethylene glycol jet is 1.58. In addition, as the capillary number continues to increase, the growth rate of bending jet length, whipping jet maximum amplitude, atomization angle, and atomization area of the ethanol are greater than those in the whipping characteristics of ethylene glycol. This phenomenon is attributed to the stronger viscous dissipation effect of ethylene glycol, which suppresses the development of jet instability.

This review summarizes recent advances in mechanochemistry-driven CO 2 conversion, highlighting representative systems, mechanistic insights, and key challenges for future development.

Spray flash evaporation is crucial for low temperature energy conversion efficiency, yet achieving precise control remains challenging. This study introduces a sweeping R134a nozzle designed to enhance and control spray flashing through internal mixing and oscillating dynamics. Using high-speed scattering-illumination imaging, proper orthogonal decomposition (POD) analysis, K-type thermocouple, and the enhanced Duhamel theorem, we investigate internal flow instabilities and external thermal performance during unsteady phase changes. Results show that operating pressure influences internal flow dynamics, with higher pressures (i.e., 800 kPa) amplifying unsteady effects (i.e., 194 Hz), indicative of rapid phase changes and momentum-driven turbulence. POD qualitatively identifies distinct energy scaling laws (i.e., -3/5 for scalar turbulence and -11/9 for stratified/ rotating flows), highlighting heterogeneous interactions in the mixing region. Interactions between incoming and returning feedback flows generate unsteady perturbations, shifting external spray behavior to intermittent spreading. Specifically, the spray plume exhibits breakup and reformation, transitioning between dense and fragmented states. This self-regulating mechanism prevents persistent thermal resistance by balancing liquid film deposition and evaporation, ensuring sustained heat transfer. At narrow nozzle height (z/D = 20), the transient heat transfer quantifies 155 W/cm2 maximum heat flux and -22 degrees C minimum temperature. These findings provide valuable insights for optimizing phase-change-driven thermal managements, where internal expansion dynamics govern flow stability and phase-change kinetics, contributing to efficient and sustainable energy systems.

The purpose of this study is to investigate the influence of earthworm surface texture on the lubrication performance of hydrostatic thrust bearings. The lubrication performance is evaluated based on the oil film load-carrying capacity and oil film temperature field under normal, high-speed, and heavy-load conditions. The semicylindrical texture mimicking the earthworm's unique surface structure was applied to the oil sealing edge of hydrostatic thrust bearings. Numerical simulations were conducted to systematically analyze the effects of texture position, number, and depth on the oil film temperature and pressure fields under normal, high-speed, and heavy-load conditions. The earthworm textures effectively improved the load-carrying capacity of the hydrostatic thrust bearing oil film, while exerting a negligible effect on the oil film temperature field. The optimal lubrication performance was achieved when the textures were arranged at Position 2 on the countercurrent side of the inner cavity oil sealing edge, with 9 textures and a depth of 3 mm. The maximum discrepancy between simulation results and experimental findings was 3%, confirming the accuracy of the numerical method. This study demonstrates the effectiveness of earthworm surface textures in improving hydrostatic thrust bearing performance and provides valuable theoretical guidance for practical engineering applications.

This study presents a comprehensive study on flow characteristics and gas–liquid interaction mechanisms in shaftless rim-driven thrusters (RDTs). The effect of key parameters, including inflow velocity, inlet gas volume fraction (IGVF) and bubble diameter distribution (0.1 mm, 0.2 mm, 0.3 mm and Gaussian-distributed 0.1-0.3 mm), were systematically analyzed. A three-dimensional RDTs model was established. The internal flow field was solved using CFD (Computational Fluid Dynamics) approach based on the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the Eulerian two-phase model. The results indicate that the presence of gas significantly alters the internal flow structure of the RDTs. Compared with pure water, gas-liquid two-phase flow induces stronger flow separation and increases the low-velocity region within the blade passage. The degree of flow separation increases as IGVF increasing, reaching the maximum state at moderate IGVF = 5%, beyond which the influence of further gas increase becomes less pronounced. Bubble diameter also plays a critical role in flow evolution. Smaller bubbles exhibit stronger flow-following behavior and promote flow uniformity, whereas larger bubbles enhance phase slip, local accumulation and flow instability, leading to increased separation and non-uniformity.

This study presents a serpentine parallel liquid-cooled plate with a novel arrangement of partitioned fins for lithium-ion battery thermal management. A collaborative framework integrating orthogonal design, hybrid surrogate models, and the NSGA-II algorithm is employed to systematically address the design challenge, aiming to improve upon the efficiency and scope of traditional single-method approaches. Orthogonal experiments first identified the influence levels of four key parameters, including fin arc degree, height, thickness, and coolant mass flow rate. Subsequently, a hybrid surrogate modeling strategy was developed using 40 sets of computational data generated by Optimal Latin Hypercube Sampling (OLHS). The Kriging model predicted maximum temperature and pressure drop, while the Response Surface Model (RSM) predicted the maximum temperature difference, with all models achieving a coefficient of determination (R2) greater than 0.98. Multi-objective optimization with NSGA-II yielded 170 Pareto-optimal solutions that effectively reveal the trade-off between cooling performance and flow resistance. The recommended multi-objective optimization liquid cooling plate can maintain the maximum battery temperature at 30.25 degrees C under a 3C discharge rate, while reducing the system pressure drop by 60.6% compared to the best orthogonal design. Robustness tests confirmed superior performance across varying operating conditions. This work provides a reliable foundation for designing high-efficiency, low-energy-consumption battery thermal management systems.

Metal-organic framework (MOF)-derived carbons have emerged as exceptional electrode materials for supercapacitors, benefiting from their ultrahigh surface areas, tunable porous structures, and inherent metal/metal oxide species. This work demonstrates a one-step laser-scribing strategy to directly convert a polyimide/MIL-101(Cr) composite film into an integrated electrode of porous laser-induced graphene (LIG) and mixed-valence chromium oxides (CrOx) for flexible in-plane micro-supercapacitors. The resulting LIG/CrOx composite exhibits a threefold enhancement in specific surface area (130.45 m(2)/g) compared to pristine LIG, along with a narrow pore size distribution (3-5 nm). The incorporated mixed-valence CrOx nanoparticles provide pseudocapacitance and enhance interfacial charge transfer, while the robust LIG network ensures mechanical flexibility and structural integrity. These synergistic structural and electrical optimizations yield an extraordinary 18-fold increase in areal capacitance, achieving 13.48 mF/cm(2) for LIG/CrOx-based planar micro-supercapacitors. The hybrid electrode maintains good cycling stability and mechanical flexibility. This study provides an efficient manufacturing pathway for high-performance flexible energy storage devices and advances the direct integration of MOFs into laser-fabricated electronic systems.

Nucleate boiling of nanofluids on porous media is a highly efficient enhanced boiling approach, as it comprehensively integrates surface treatment and liquid modification. However, nanoparticle sedimentation typically causes instability in nanofluids and may even induce pore clogging, thereby deteriorating boiling performance—this issue is particularly prevalent in nanofluid heat pipes. Herein, an electrostatic field is proposed to address the thermal challenges stemming from nanoparticle deposition and accumulation within pores, specifically by facilitating the movement of nanoparticles. This enhancement primarily derives from nanoparticle-mediated heat exchange, improved thermal conductivity, and the fragmentation of large bubbles driven by electrostatic fields. Notably, for porous structures with small pore sizes, the electrostatic field exhibits a marked enhancement effect on nanofluid boiling: relative to zero-field conditions, the maximum enhancement factor of heat transfer coefficient (HTC) reaches 2.64 and the highest critical heat flux (CHF) enhancement ratio reaches 1.61, both obtained on the PS-40 surface. Furthermore, new semi-analytical models for heat flux and CHF enhancement ratio are developed, incorporating the effects of electric field strength, surface tension, porosity, and nanofluid concentration. This study offers key insights into addressing the problem of “dry-out” in nanofluid heat pipes, which is triggered by pore clogging induced by nanoparticle deposition.

The coalescence of droplets at the air-water interface is a fundamental phenomenon, governing processes such as aerosol generation, spray formation, and interfacial mass transfer. However, the potential energy partitioning behaviors and the coalescence dynamics are still not well understood. Therefore, this paper investigates the coalescence dynamics of droplet at air-water interface under direct current (DC) electric fields. The numerical results obtained by present simulations using volume-of-fluid (VOF) method exhibited good agreement with experimental data reported in the literature. The effects of electric field and velocity field on the coalescence process between a droplet and air-water interface was systematically discussed and analyzed. Different electric field and velocity field configurations correspond to distinct droplet contact modes and energy partitioning behaviors. In the absence of initial droplet velocity (We=0), the viscous dissipation energy (E mu/Etotal = 0.3-0.5) and electric energy (Ee/Etotal = 0.3-0.6) account for a major proportion of the total system energy. The electric field induces localized velocities (Up); however, the corresponding kinetic energy (Ek/Etotal = 0.02) represents only a minor proportion of the total system energy. And the coalescence modes include tip-streaming breakup, , elliptic PC mode, , partial coalescence,, complete coalescence. . In the presence of initial droplet velocity (We=24.95-224.55), We =24 . 95- 224.55), kinetic energy becomes the dominant contributor. The viscous dissipation energy , the kinetic energy accounts for a major part of the total system energy. Under varying initial velocity regimes, this study elucidates the regulatory mechanisms of kinetic energy, electric energy, and viscous dissipation energy, thereby contributes to an improved understanding of the mechanism of droplet-interface electrocoalescence.

Single crystal diamond and polycrystalline diamond wafers are interesting heat spreader candidates. High quality and large size of these is demanded by industry, albeit at low price. Highly textured diamond wafers can be a good balance between large area wafer design, improved processability, thermal performance, and cost. This study investigates the synthesis of 3-inch {100} and {110}-textured diamond wafers with particular attention to growth rate, homogeneity of the grain orientation, grain size, and diamond quality. By two-step deposition methods, highly textured diamond grains with grain size larger than 150 μm and thickness of ca. 1 mm were homogenously distributed across the whole 3-inch wafer, with a growth rate of around 5 μm/h. The established homogeneous {100} or {110} facets obtained by the two-step methods are contrasted by single step deposition methods, which yield either no texture or gradual changing texture. The establishment of the homogeneous {100} texture is explained in terms of evolutionary selection during CVD growth and the growth factors α, β, and γ. For {100}-textured thick diamond film, α was controlled to nearly 3.0 at the beginning of growth followed by 1.0. The thermal conductivities are improved for textured diamond wafers compared to the untextured wafers. The cross-plane is higher than the in-plane thermal conductivity for the highly textured diamond wafer. For instance, the in-plane and cross-plane thermal conductivities of the {100}-textured diamond wafer were 1130 and 1340 W/(mK), respectively, with the highest anisotropic ratio (1.2) among all samples. The results signify the good balance of homogeneous large area deposition, thermal properties, growth rate, and cost. Thus, highly textured diamond wafers are anticipated to stimulate adoption of diamond wafers as heat spreader in CPU/GPU chiplets, GaN HEMT and semiconductor devices.

Controlling fugitive dust emissions during coal unloading in semi-open port environments remains a critical challenge due to susceptibility to ambient airflow and the limited efficacy of conventional suppression methods. This study employs numerical simulation to characterize the dust dispersion dynamics and subsequently develops a novel wind-assisted electrospray suppression system for coal unloaders. The atomization characteristics, droplet transport behavior, and on-site dust suppression efficacy were investigated. Simulation results indicate that the impact airflow from falling coal entrains dust into upward-propagating vortex clusters, leading to leakage primarily at the hopper corners. The wind-assisted electrospray dust suppression system produces droplets with a size range of 20-100 mu m. Optimal performance parameters were identified as a gas-to-liquid ratio (GLR) of 0.086, an applied voltage (U) of 16 kV, a nozzle height (h) of 30 cm, and an installation angle (theta) of 0 degrees. Compared to the conventional dust suppression system, the new system improves suppression efficiency by over 55%, particularly in capturing PM2.5 particles. This system reduces water consumption by 89% and results in operational cost savings of 16,943.6 RMB/h. This work pioneers the engineering application of wind-assisted electrospray technology in semi-open spaces, offering a new technical reference for fugitive dust control.

This study investigates the desulfurization performance of four absorbents (sodium hydroxide NaOH, calcium hydroxide Ca(OH)2, calcium carbonate CaCO3, and deionized DI water) in a visualized electrospray absorption tower. Increasing the applied voltage (U) significantly enhances atomization quality, thereby expanding the gasliquid interfacial area and raising the droplet charge-to-mass ratio. Both the SO2 absorption efficiency (eta) and the overall mass transfer coefficient (Kg alpha) increase with U, exhibiting a strong dependence on the absorbent type. For highly soluble NaOH and moderately soluble Ca(OH)2, eta at 10 kV more than doubles compared to the uncharged state (U = 0 kV). This marked enhancement arises from two synergistic effects: a physical enhancement from the enlarged interfacial area and a chemical enhancement from electric field-driven migration of OH- to the droplet surface. Conversely, CaCO3 and DI water show limited improvement (< 50 %) due to insufficient OH- availability. The gas-phase mass transfer coefficient (Kg) depends on the electrohydrodynamic atomization mode, remaining stable in dripping mode, decreasing in microdripping mode, and increasing again in oscillating microdripping mode. These findings establish a clear correlation between electrospray characteristics and desulfurization performance, offering crucial guidance for optimizing the absorbent selection and operating parameters in high-efficiency wet flue gas desulfurization systems to reduce water and energy consumption.

Electrohydrodynamic manipulation of oil-water interfaces is a promising route for intensified separation and emulsion control, yet a molecular-level picture of how coupled electric and rotating flow fields (RF) dictate droplet stability is still lacking. In this paper, molecular dynamic (MD) simulations are performed to elucidate the droplet polarization, deformation, breakup and stability under direct current (DC) field, alternating current (AC) field, pulsed electric field (PEF) and rotating electric field (RE), respectively, acting simultaneously with a RF field. The results show that (i) the nature of the electric field dominates the breakup threshold: DC fields stretch droplets continuously and give the lowest critical electrocapillary number (Ca-E), whereas the periodic reversal of AC fields favor rapid retraction and afford the highest stability; overall stability follows the order of AC field > RE field > PEF field > DC field. (ii) Coupling electric and centrifugal forces significantly amplifies droplet deformation; an appropriate angular velocity, however, suppresses breakup and enlarges the droplet stability. (iii) Dipole moment build-up and hydrogen-bond depletion are identified as molecular signatures of impending instability: DC fields induce the fastest loss of hydrogen bonding, while AC and RE fields mitigate electrostatic overstretching and preserve interfacial structure. (iv) Optimizing electric-field frequency (5-6.7 GHz for PEF) and introducing Span-80 and SiO2 synergistic effects enhance stability, efficiently suppressing breakup even under strong fields. These findings clarify how electric and hydrodynamic forces, together with interfacial additives, synergistically manipulate droplet stability, and provide theoretical guidance for the design of high-efficiency electro-centrifugal separators.

The preparation of electrocatalysts with great hydrogen production performance by facile synthesis methods still remains a challenge. In this study, a facile method was used to prepare oxygen-doped MoS2 with a high metal content (71.7%) by alcohol-thermal method with exfoliation and applied to hydrogen evolution reaction (HER). The enhancement of the HER performance was achieved by effectively modulating the crystal phase of MoS2 through adjustment in the precursor solution composition. Experimental results reveal that MoS2 synthesized with optimal ethanol addition has the richest 1-tetragonal (1 T) phase content. The optimized MoS2 electrocatalyst demonstrated exceptional HER activity with a low overpotential of 142 mV at 10 mA cm-2, small Tafel slope (69.14 mV dec-1) and remarkable long-term stability. Furthermore, the prepared catalysts exhibit great stability under neutral and alkaline conditions. Further research has found that factors such as the dielectric constant, boiling point and viscosity of the solvent affect the pyrolysis degree of the sulfur precursor by the solvent, thus influence the formation of the 1 T phase. Density functional theory calculations confirm that the 1 T-phases-riched MoS2 exhibits optimized hydrogen adsorption and enhanced charge transfer efficiency. The research results provide a facile synthesis process method of MoS2 with high electrocatalytic activities.

Metal-sulfur batteries have attracted increasing attention as promising energy-storage systems because of their high theoretical energy density, low cost, and environmental compatibility. However, the temperature sensitivity of metal-sulfur batteries severely degrades their electrochemical performance at extreme temperatures. It is therefore critical to develop stable and long-lasting metal-sulfur batteries that operate over a wide temperature range. Herein, a comprehensive insight into metal-sulfur batteries operating over wide temperature ranges is presented. The general principles of various metal-sulfur batteries and their temperature dependence are first introduced. Subsequently, the critical challenges facing metal-sulfur batteries are discussed. We then systematically elucidate solution strategies from the perspective of cathode design, anode tailoring, electrolyte modulation, and separator modification. These strategies are discussed in relation to their ability to address the key limitations that compromise the electrochemical performance and stability of metal-sulfur batteries. Lastly, the conclusion and outlook identify several crucial issues for further research to resolve the key challenges facing metal-sulfur batteries. Overall, this review will not only enhance our understanding of metal-sulfur batteries but also provide valuable insights into cutting-edge energy storage systems with superior performance, robust safety features, and a wide operating temperature range.