Removal Mechanism Research Articles

Investigation of dissolution behavior and surface integrity in electrochemical machining of nickel-based superalloys

ABSTRACT Dissolution behavior and surface integrity during the electrochemical machining (ECM) of nickel-based superalloys are vital for the performance of components. This study examines IN718, 718Plus, and Rene 65 alloys focusing on material removal mechanisms, surface morphology, intergranular corrosion, three-dimensional profiles, surface roughness, microhardness, and residual stresses. The results indicated that as the current density increased, the MRR of all three alloys increased linearly, while the current efficiency initially fluctuated before stabilizing. At low current densities, selective dissolution and intergranular corrosion resulted in rough surfaces for the alloys examined. In contrast, higher current densities produced smooth and uniform surfaces for these alloys. After electrochemical treatment, the surface microhardness of all alloys was reduced, and there was a slight decrease in residual stresses as well. These findings support the development of more precise and effective strategies for achieving higher surface integrity in the ECM of nickel-based superalloys.

Investigation of the Thermophysical Simulation and Material Removal Mechanism of the High-Volume-Fraction SiCp/Al Composite in Wire Electrical Discharge Machining

SiC particle reinforced aluminum matrix composites (SiCp/Al) are widely used in aviation, weaponry, and automobiles because of their excellent service performance. Wire electrical discharge machining (WEDM) regardless of workpiece hardness has become an alternative method for processing SiCp/Al composites. In this paper, the temperature distribution and the discharge crater size of the SiCp/Al composite are simulated by a thermophysical model during a single-pulse discharge process (SPDP) based on the random distribution of SiC particles. The material removal mechanism of the SiCp/Al composite during the multi-pulse discharge process (MPDP) is revealed, and the surface roughness (Ra) of the SiCp/Al composite is predicted during the MPDP. The thermophysical model simulation results during the MPDP and experimental characterization data indicate that the removal mechanism of SiCp/Al composite material consists of the melting and vaporization of the aluminum matrix, as well as the heat decomposition and shedding of silicon carbide particles. Pulse-on time (Ton), pulse-off time (Toff), and servo voltage (SV) have a great influence on surface roughness. The Ra increases with an increase in Ton and SV, but decreases slightly with an increase in Toff. Moreover, compared with experimental data, the relative error of Ra calculated from the thermophysical model is 0.47–7.54%. This means that the developed thermophysical model has a good application and promotion value for the WEDM of metal matrix composite material.

Removal of Phosphate from Water by Iron/Calcium Oxide-Modified Biochar: Removal Mechanisms and Adsorption Modeling

Phosphorus (P) pollution is a leading cause of water eutrophication, and metal-modified biochar is an effective adsorbent with the ability to alter the migration capacity of phosphorus. This study uses bamboo as the raw material to prepare metal-modified biochar (ZFCO-BC) loaded with Fe and Ca under N2 conditions at 900 °C, and investigates its adsorption characteristics for phosphate. Batch experimental results show the adsorption capacity of the ZFCO-BC gradually increases (from 4.0 to 69.1 mg/g) as the initial phosphate concentration increases (from 2 to 900 mg/L), mainly through multilayer adsorption. Additionally, as the pH increases from 1 to 7, the adsorption capacity of the ZFCO-BC climbs to reach its maximum value of 48.4 mg/g with an initial phosphate concentration of 150 mg/L. At this pH, phosphate primarily exists as H2PO4− and HPO42−, which both readily react with Fe3+ and Ca2+ in the biochar. Furthermore, the addition of CO32−, HCO3−, NO3−, SO42−, F−, and Cl− each affect the removal rate of phosphate by less than 10%, indicating the ZFCO-BC has a highly efficient and selective phosphate adsorption capacity. A multi-column adsorption experiment designed to achieve long-term and efficient phosphorus removal treated 275.5 pore volumes (PVs) of water over 366 h. The cyclic adsorption–desorption experiment results show that 0.5 M NaOH can effectively leach phosphate from the ZFCO-BC. Observations at the molecular level from P K-edge XANES spectra confirm the removal of low-concentration phosphate is primarily dominated by electrostatic attraction, while the main removal mechanism for high-concentration phosphate is chemical precipitation. This study demonstrates that ZFCO-BC has broad application prospects for phosphate removal from wastewater and as a potential slow-release fertilizer in agriculture.

Dynamic Spatio-Temporal Hypergraph Convolutional Network for Traffic Flow Forecasting

Graph convolutional networks (GCN) are an important research method for intelligent transportation systems (ITS), but they also face the challenge of how to describe the complex spatio-temporal relationships between traffic objects (nodes) more effectively. Although most predictive models are designed based on graph convolutional structures and have achieved effective results, they have certain limitations in describing the high-order relationships between real data. The emergence of hypergraphs breaks this limitation. A dynamic spatio-temporal hypergraph convolutional network (DSTHGCN) model is proposed in this paper. It models the dynamic characteristics of traffic flow graph nodes and the hyperedge features of hypergraphs simultaneously, achieving collaborative convolution between graph convolution and hypergraph convolution (HGCN). On this basis, a hyperedge outlier removal mechanism (HOR) is introduced during the process of node information propagation to hyper-edges, effectively removing outliers and optimizing the hypergraph structure while reducing complexity. Through in-depth experimental analysis on real-world datasets, this method has better performance compared to other methods.

Study on the Effect of Conditioners on the Degradation of Tetracycline Antibiotics in Deer Manure Composting

The unscientific disposal of agricultural solid waste introduces more antibiotics and other pollutants into the environment. Composting, as an environmentally friendly solid waste disposal method, can be used as a green way to degrade antibiotics, and conditioners can regulate the physicochemical indicators of the composting process. This article investigates the removal mechanism of tetracycline antibiotics (TCs) during the composting process by adding different regulators (biochar, zeolite, and biochar + zeolite). The results showed that the conditioning agent could significantly improve the removal efficiency and removal rate of TCs in compost. Among them, the addition of the zeolite group had the highest degradation rate of TCs, which were 91.39% (Tetracycline), 97.18% (Chlortetracycline), and 95.68% (Oxytetracycline). The combination of biochar and zeolite conditioning agents effectively minimized the migration of TCs into the soil. According to the findings of the artificial neural network model, it was determined that TCs exhibited the highest sensitivity to biochar + zeolite modulators at 31.28%. Conditioners influenced the removal of TCs in compost by impacting their physicochemical properties and microbial community structure. We isolated and domesticated a suitable microbial preparation that promotes the degradation of TCs, including Acinetobacter pittii, Stenotrophomonas maltophilia, Lactobacillus reuteri, Pseudomonas putida, and Trichosporon dohaense.

Boosting Electrochemical Degradation of Water Pollutants Using Sulfur‐Rich Porous Polyimide‐Derived Laser‐Induced Graphene Catalytic Membrane

Water pollution is an inevitable concern associated with technological advancement. To address this problem, it is necessary to significantly shorten the manufacturing process of porous materials while enabling effective pollutant removal. Herein, a facile, rapid, and scalable approach is reported to obtain sulfur‐doped hierarchically porous laser‐induced graphene (S‐LIG) as a catalytic membrane with three‐dimensional networks by localized laser irradiation, along with possible adsorption and electrochemical degradation mechanisms for pollutant removal. S‐LIG is derived from sulfur‐containing porous polyimide film which is prepared via thermally induced phase separation followed by stepwise thermal imidization. Methylene blue (MB) adsorption behavior on the S‐LIG membrane closely fits the pseudo‐second‐order and Freundlich isotherm models, suggesting a complex sorption mechanism, including both strong chemical interaction and physical adsorption. Furthermore, S‐doping enhances catalytic activity for generating reactive oxygen species (ROS), aiding MB degradation via indirect oxidation, and improves direct oxidation on the anode by accelerating electron transfer at the electrodes. This results in a stable 93% MB degradation at a low 1.5 V after 24 h. Additionally, the impact of solution pH reveals that electrostatic attraction forces under basic conditions and the high generation of ROS under acidic conditions favor adsorption and electrochemical oxidation.

Prediction of the material removal rate in bonnet polishing using a Bayesian optimization deep neural network

The material removal mechanism in robotic bonnet polishing is complex and influenced by multiple factors, necessitating an appropriate method to establish a material removal model. This study employs a Bayesian optimized deep neural network (BO-DNN) to model the intricate relationship between polishing parameters and material removal rate (MRR) using removal function spot experimental data. The tree-structured Parzen estimator (TPE) improves model convergence speed and accuracy, while particle swarm optimization (PSO) assists in inverse verification. Results show that the BO-DNN model achieves a root mean square error (RMSE) of 0.0293 and a Pearson correlation coefficient (PCC) of 99.42% for the total sample, representing approximately a 50% improvement in predictive accuracy over the unoptimized DNN model. The inverse verification results closely match the experimental data, confirming the model’s reliability. This study offers theoretical insights and practical references for advancing robotic bonnet polishing technology.

Design of the electrode structure for the dust removal efficiency optimization of electrostatic precipitator

Abstract Air dust pollution prevention and control is a global environmental concern. Electrostatic precipitators (ESPs) play a crucial role in dust pollution control, and its electrode structure significantly affects plasma parameters and the movement of charged dust particles, which in turn influences the dust removal efficiency. This study focuses on optimizing the commonly used wire-plate dust removal device, experimental research is conducted first, revealing that the hole-hole electrode structure of an ESP exhibits higher peak currents at the same voltage compared to both plate-hole and plate-plate electrode configurations. For the removal efficiency of particles with a radius greater than 1 μm, the ESP with a hole-hole electrode structure performs better than those with plate-hole and plate-plate electrode structures. Moreover, the particle collection efficiency is positively correlated with particle radius, larger particles correspond to higher dust removal efficiency. Based on experimental findings, simulations are conducted to provide a deeper analysis and understanding of the dust removal mechanisms of ESPs. This paper primarily utilizes COMSOL Multiphysics numerical simulation software to simulate traditional wire-plate ESPs and a new wire-hole ESP. It explores the multiphysical characteristics of ESPs under different electrode structure configurations, and investigates in depth the impact of electrode structure on dust removal efficiency. The simulation results indicate that compared to flat collecting electrodes, porous collecting electrodes exhibit a significant increase in electric field intensity at the openings, and they have a lower surface charge density than flat plates, thereby reducing reverse corona phenomena. Ion wind affects the internal airflow dynamics of ESPs, thereby influencing their efficiency in capturing fine particulate matter. This negative impact of ion wind can be mitigated by introducing perforations in the collection plates.

Luminescent Multifunctional Nanomaterials: Capacitive Removal and Enhanced Detection Efficiency of Heavy Metals Ions for Advanced Water and Wastewater Treatment Application

AbstractIn recent years, heavy metal ions pollution in the industrialized environment of the societies threaten human health that flaunt ill‐sorted blueprints in freshwater resources obviously. The paradigm of designing luminescent multifunctional nanomaterials finds directions to the strategies of synthesizing cost‐effective, green, and versatile nanomaterials not only for detection, but also removal process of heavy metal ions in large scale applications. Among them, discovering the advances of luminescent multifunctional nanomaterials provides broad types of biomaterials, polymers and porous nanoparticles that grabs focal of investigations over the past several years due to their unique advantages such as enhanced detection efficiency with lowest limit of detection (LOD), minimum ions interference in versatile removal process, fast responsivity and selectivity as outstanding as unique physicochemical properties. This review paper tries to highlight the paradigm of principles for design, development, and utilization of luminescence nanomaterials for considering fundamental detection and removal mechanisms of heavy metal ions. In particular, these nanomaterials increase the remediation quality that are tackled in detail by focusing on opportunities and challenges in the field. Finally, design methods of these nanomaterials and concentrating on empowered detection and removal efficiency for heavy metals ions highlights novel prospective and strategies for largescale applications.

MgAl-Layered Double Hydroxide-Coated Bio-Silica as an Adsorbent for Anionic Pollutants Removal: A Case Study of the Implementation of Sustainable Technologies.

The adsorption efficiency of Cr(VI) and anionic textile dyes onto MgAl-layered double hydroxides (LDHs) and MgAl-LDH coated on bio-silica (b-SiO2) nanoparticles (MgAl-LDH@SiO2) derived from waste rice husks was studied in this work. The material was characterized using field-emission scanning electron microscopy (FE-SEM/EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopic (XPS) techniques. The adsorption capacities of MgAl-LDH@SiO2 were increased by 12.2%, 11.7%, 10.6%, and 10.0% in the processes of Cr(VI), Acid Blue 225 (AB-225), Acid Violet 109 (AV-109), and Acid Green 40 (AG-40) dye removal versus MgAl-LDH. The obtained results indicated the contribution of b-SiO2 to the development of active surface functionalities of MgAl-LDH. A kinetic study indicated lower intraparticle diffusional transport resistance. Physisorption is the dominant mechanism for dye removal, while surface complexation dominates in the processes of Cr(VI) removal. The disposal of effluent water after five adsorption/desorption cycles was attained using enzymatic decolorization, photocatalytic degradation of the dyes, and chromate reduction, satisfying the prescribed national legislation. Under optimal conditions and using immobilized horseradish peroxidase (HRP), efficient decolorization of effluent solutions containing AB-225 and AV-109 dyes was achieved. Exhausted MgAl-LDH@SiO2 was processed by dissolution/precipitation of Mg and Al hydroxides, while residual silica was used as a reinforcing filler in polyester composites. The fire-proofing properties of composites with Mg and Al hydroxides were also improved, which provides a closed loop with zero waste generation. The development of wastewater treatment technologies and the production of potentially marketable composites led to the successful achievement of both low environmental impacts and circular economy implementation.

Numerical Approximation Tool Prediction on Potential Broad Application of Subsurface Vertical Flow Constructed Wetland (SSVF CW) Using Chromium and Arsenic Removal Efficiency Study on Pilot Scale

\noindent {\bf Abstract:} This study investigates the potential broad application of Subsurface Vertical Flow Constructed Wetlands (SSVF CWs) for heavy metal remediation, focusing on Chromium (Cr) and Arsenic (As) removal efficiency. A pilot-scale experimental setup was employed, utilizing a SSVF CW filled with 12 mm gravel and 2 mm coarse sand, planted with Phragmites Australis. The research, conducted over 366 days, aimed to develop a numerical approximation tool to predict the performance and applicability of SSVF CWs in various environmental conditions. The experimental system operated at a hydraulic loading rate of $98-111 \mathrm{~mm} / \mathrm{d}$ and a hydraulic retention time of 6 days. Results showed average removal efficiencies of $44.87 \pm 9.52 \%$ for Cr and $43.16 \pm 9.43 \%$ for As. A mass balance analysis revealed that substrate accumulation was the primary mechanism for heavy metal removal, accounting for $29 \%$ of Cr and $26 \%$ of As removal. Plant uptake contributed to $3.5-9.9 \%$ of Cr and $0.3-$ $8.8 \%$ of As removal. Based on these findings, a numerical model was developed to simulate SSVF CW performance under varying environmental and operational parameters. The model incorporated factors such as influent concentrations, hydraulic loading rates, substrate composition, and plant species. Validation against experimental data showed good agreement, with an $\mathrm{R}^{2}$ value of 0.89 . The numerical tool was then used to predict SSVF CW performance across a range of scenarios, indicating potential broad applications in industrial wastewater treatment, mine drainage remediation, and contaminated groundwater cleanup. This study provides valuable insights into the scalability and versatility of SSVF CWs for heavy metal removal, offering a sustainable and cost-effective solution for water treatment challenges.\\

Predicting the removal efficiency of titanium dioxide nanoparticles in an activated sludge system using fate modeling depending on the operating conditions

Wastewater treatment plants (WWTPs) are a major discharge pathway for engineered nanoparticles (ENPs) that can potentially impact aquatic systems, making it crucial to understand ENP behavior in these facilities. In this study, we developed a fate model for titanium dioxide (TiO2) nanoparticles (NPs) to predict their removal efficiency (RE) in activated sludge (AS) systems. The model, based on material balance equations for free and sludge-attached TiO2 NPs, incorporated a linear-adsorption partition coefficient (Kd) and pseudo-second-order kinetics for TiO2 NP attachment to the activated sludge. Validated with data from three WWTPs, the model investigated RE correlations with inflow TiO2 NP concentration, sludge retention time (SRT), hydraulic retention time (HRT), mixed liquor suspended solid (MLSS) concentration, and water temperature. The model reasonably predicted the comparative performance of the WWTPs but underestimated the RE by up to ∼29 %, probably due to system simplification, limited Kd data, the presence of other Ti-containing NPs besides TiO2 NPs, and unincorporated removal mechanisms such as sweeping in the secondary clarifier. The model revealed favorable design/operating conditions for increasing the TiO2 NP RE of the AS system: shortening the SRT, increasing the MLSS concentration, and increasing the water temperature. The developed model could be useful for estimating and comparing the expected TiO2 NP REs across different WWTPs under varying operating conditions or for tracing the material flow and fate of TiO2 NPs in environmental compartments involving WWTPs, both regionally and country-wide.

Optimizing the low-temperature performance of high-wax-content crude oil with emulsion-based wax inhibitors: Mechanisms and efficacy.

Wax deposition in constant-temperature transportation of waxy oil with high pour points poses a significant challenge for the oil industry. The demand for efficient methods to solve wax deposition has gained attention. To elucidate the impact of emulsion-based wax inhibitors on the performance of crude oils with varying wax content at low temperatures, experiments, rheological analyses, and microscopic analyses were conducted to study their pour point regulation, low-temperature flow improvement, wax prevention effectiveness, and wax crystallization behavior. The results indicate that emulsion-based wax inhibitors significantly reduce the pour point of crude oil, especially for high-wax-content oil, while for low-wax-content oil, the pour point only decreased by 3°C. By penetrating and dispersing wax crystals, the inhibitor reduced the viscosity of crude oil at low temperatures, enhancing its flowability. At 28°C, crude oil transitioned from a shear-thinning non-Newtonian fluid to a Newtonian fluid at wax inhibitor dosages of 500-750ppm. At 1000ppm, the wax prevention rate for high-wax-content oil reached 87.5%, but the effect plateaued beyond this concentration. Additionally, the wax prevention and removal mechanism of the emulsion-based wax inhibitors is discussed. This study confirms that emulsion-based wax inhibitors significantly enhance the low-temperature processability of crude oil, offering a viable strategy for the conveyance and refinement in cold climates.

Research on chromium removal mechanism by electrochemical method from wastewater

Cr (VI), a heavy metal ion in electroplating wastewater, poses a significant environmental challenge due to its high toxicity and recalcitrance to degradation. This paper used copper plates, stainless steel, foam carbon, and carbon paper as electrodes to research the chromium removal mechanism from electroplating wastewater by a fast electrochemical method. The effect of the electrode materials and reaction conditions on removing Cr (VI) from wastewater was investigated. The analysis of the Cr (VI) removal rate during electrolysis revealed that the optimal electrode materials used the copper plate as the cathode and foam carbon as an anode. The optimal reaction conditions were determined: the electrolysis time is 30 min, the plate spacing is 2.0 cm, the operating voltage is 1.8 V, and the reaction temperature is 50 °C, achieving a maximum Cr (VI) recovery of 91.30 %. The proposed optimization of stirring instead of heating was found to be feasible. At 300 r/min, the energy consumption can be significantly reduced, and the removal rate of Cr (VI) can reach 87.82 %. The intrinsic mechanism behind the removal of Cr (VI) was studied by calculating the adsorption performance of the two electrodes on Cr (VI) and Cr (III) using the density functional theory (DFT), providing an in-depth understanding of the action mechanism and industry applications.

Internal mechanism of microbial nitrogen removal under prolonged low-temperature stress: A focus on microbial communities, metabolic pathways, and microbial function

Low temperature restricts the stable treatment of wastewater in alpine and high-altitude regions. However, the internal mechanism of microbial functional succession at low temperatures remains unknown. To illustrate the internal mechanism by which low temperatures affect wastewater treatment, high-throughput 16S and metagenomic sequencing were employed. Results revealed that microorganisms effectively removed pollutants under prolonged low-temperature stress (3–8 °C). The removal efficiencies forchemical oxygen demand, NH4+-N, and total nitrogen were 80.80 %–95.18 %, 87.91 %–99.82 %, and 32.67 %–69.88 %, respectively. The relative abundance of Nitrospira and Nitrosomonas increased by 102.50 % and 276.92 %, respectively. Additionally, the relative abundance of heterotrophic nitrobacteria, including Terrimonas, Rhodobacter, and Ferribacterium, increased significantly, with values increasing by 34.63 %, 22.04 %, and 129.64 %, respectively. These bacteria became dominant. Metagenomic analysis revealed that low temperatures can inhibit membrane transfer. However, the functional genes for electron production and electron carriers were upregulated, thus promoting the ability of microorganisms to metabolize nitrogen. Moreover, the abundance of functional genes involved in extracellular electron transfer (pili, c-type cytochromes, and flagella) increased, which improved the nitrogen removal capacity. This study provides novel perspectives on the internal mechanism of microbial nitrogen removal under prolonged low-temperature stress.

Force model based on heterogeneous components decoupling and machining behaviors of ultrasonic grinding continuous fiber-reinforced MMCs

Continuous fiber-reinforced metal matrix composites (CFMMCs), such as SiC fiber-reinforced TC17 matrix composites (SiCf/TC17), are renowned for their exceptional mechanical properties. However, their heterogeneous compositions present significant machining challenges, including fiber pullout, matrix cracking, and accelerated tool wear. Ultrasonic vibration-assisted grinding (UVAG) has proven to be an effective technique for overcoming these challenges. The material removal mechanisms in UVAG, especially in composites with both ductile and brittle phases, remain poorly understood. To explore these issues, UVAG and conventional grinding (CG) experiments were conducted on SiCf/TC17 along two grinding directions: fiber’s transverse direction (FT) and fiber’s longitudinal direction (FL). This paper aims to provide a new dynamic mechanical model and shed light on the complex removal mechanisms in CFMMCs, which are characterized by a near one-to-one alternation of ductile and brittle phases. The findings reveal that UVAG reduces fiber damage and surface roughness compared to CG, especially when grinding along FT. UVAG lowers normal (Fn) and tangential grinding forces (Ft) by 15.3% and 12.3%, respectively. This highlights UVAG’s potential for improving the machinability of complex materials like CFMMCs. The proposed grinding force model closely matches the experimental results. This paper hopes to support the precision abrasive machining of CFMMCs, a kind of complex and highly anisotropic composite material, and promote their application in the fields such as aerospace.

Impact of saline water matrix on the removal of boron using electrocoagulation process: Unveiling performance, removal mechanism, and cost-energy evaluation

This study aimed to evaluate the impact of the water matrix on the applicability of the electrocoagulation process for boron mitigation from saline water. The effects of current density, electrolysis time, aluminum dissolution, pH, initial boron concentration, and other ions were examined. The results show that increasing current intensity initially favors aluminum dissolution and boron adsorption, but beyond a certain threshold, it leads to the rapid formation of large, inefficient aluminum hydroxide particles with reduced boron adsorption capacity. The best boron removal (72%) is achieved with a current density of 16.67 mA.cm-², an electrolysis time of 90 minutes, a pH of 8 and an initial boron concentration of 5 mg.L-¹. Nevertheless, applying this process to seawater remains challenging due to the complexity of the matrix and competitive adsorption with ions like magnesium, resulting in lower deboronation rates (20%). Furthermore, EDS, XRD, and FTIR analysis confirmed the reduced content of boron in solid samples from synthetic seawater at 20 mA.cm-² compared to 16.67 mA.cm-², indicating less efficient formation of crystalline boehmite. Kinetic studies followed Lagergren's pseudo-first-order mechanism and the intraparticle diffusion model. Finally, electrocoagulation has proved ineffective for removing boron from seawater due to its high energy consumption of 3.6 kWh.m-3.

New insights into sustainable in-situ fixation of heavy metals in disturbed seafloor sediments

To address the issues of plume formation and heavy metal ion release during deep-sea mining operations, this study employed multi-sourced mineral composite roasting materials (MMCCM) of varying sizes. An in-situ capping technique was applied within a simulated system to immobilize heavy metals in contaminated sediments. The results demonstrated that capping with MMCCM of different sizes significantly suppressed the upward migration of Cu, Co, and Ni from sediments into the overlying seawater following disturbance. Ion diffusion was identified as a key mechanism driving heavy metal migration. By calculating the release rates of heavy metals during both the disturbed and undisturbed phases, it was found that the application of MMCCM induced a negative diffusion of heavy metals, indicating that the MMCCM-sediment layer functioned as a "sink" for heavy metals. FTIR and XPS analysis showed that the primary mechanisms for heavy metal removal by MMCCM were electrostatic attraction and complexation-precipitation. Additionally, capping with MMCCM facilitated the transition of heavy metals from labile to stable forms within the sediments. Through comprehensive evaluation, the long-term effectiveness of the fixed effects was demonstrated as follows: large MMCCM (L@MCM) > medium MMCCM (M@MCM) > small MMCCM (S@MCM) > powder MMCCM (P@MCM). Finally, we proposed future research directions and introduced the DQSE framework for the sustainable application of MMCCM. Based on the above findings, this study provides new insights and research references for the in-situ immobilization of heavy metals and plume reduction during future deep-sea mining processes.

Characterization of liquid-thickness distribution in micropores on elastic surface under sliding and pressurizing conditions.

To improve the performance of studless tires on ice surfaces, the mechanism of liquid film removal must be elucidated. In this study, an experimental system is developed to simulate the running conditions of a studless tire, and the microscopic liquid film flow generated between the rubber surface and glass is observed to evaluate the liquid thickness distribution. Liquid film removal by micropores on foamed rubber samples is investigated by visualizing the liquid thickness in the micropores. The proposed system enables variations in the pressure and sliding velocity between the rubber and glass. The liquid thickness in the micropores is measured using laser-induced fluorescence, and the effects of pressure and sliding velocity on the thickness are examined. Water penetrates the micropores on the rubber sample surface, and different liquid thicknesses are obtained for each pore. The amount of liquid penetrating the pores is affected to a greater extent by the sliding velocity than by the pressure. Therefore, liquid penetration is more strongly influenced by the hydrodynamic effect of the increasing inertia of the liquid under high sliding velocities than by the elastic deformation of the pore.

Mitigating pollutants in textile dye wastewater with Aloe vera (L.) Burm. f. and Abelmoschus esculentus (L.) Moench: A study on treatment efficacy

Textile wastewater, particularly those containing dyes, presents significant threats to environmental quality and human health. This study assessed the efficacy of Aloe vera (L.) Burm. f. and Abelmoschus esculentus (L.) Moench (Okra) in removing pollutants from textile dye effluent collected in Dindigul, Tamil Nadu. The effluent samples were treated with varying doses of phyto-coagulants (0.02g, 0.04g, 0.06g, 0.08g, 0.10g, and 0.12g), as well as isolated polysaccharides from Aloe vera and Okra, to identify optimal strategies for reducing color, Total Dissolved Solids (TDS), and Chemical Oxygen Demand (COD). The findings revealed that the phyto-coagulants, particularly Okra polysaccharides, significantly reduced pollution levels, achieving a 90% reduction in color, 96% reduction in TDS, and 82% reduction in COD. To further understand the mechanism of pollutant removal, GC-MS, FTIR, and Zeta potential analyses were conducted. This study highlights the effectiveness of natural coagulants in mitigating environmental pollution and preventing the entry of harmful chemical contaminants into the food chain. The study supports the potential of Aloe vera and Okra as sustainable and eco-friendly solutions for addressing the environmental challenges posed by textile wastewater pollution.