Search Results (15,646)

This research evaluates the feasibility of using a lignocellulosic biosorbent prepared from mature leaves of Asplenium scolopendrium (produced through simple mechanical processing of the leaves, without applying any chemical modification or heat treatment) for the removal of methylene blue from water. Before and after adsorption the material was characterized using SEM technique and color analysis. Subsequently, the adsorption behavior was analyzed by examining equilibrium, kinetic, and thermodynamic aspects of the process. The equilibrium data were best represented by the Sips isotherm model, while the adsorption rate followed the Avrami model. Thermodynamic evaluation indicated that the retention of the dye occurs predominantly through a physical adsorption mechanism, while a minor contribution from chemisorption may be present, slightly enhancing the overall dye uptake. Process optimization was performed using the Taguchi experimental design, which also allowed the identification of the most significant operational variable. In addition, analysis of variance (ANOVA) was applied to quantify the contribution of each factor affecting dye removal efficiency. Among the investigated variables, time showed the strongest influence (72.65%), whereas temperature had a negligible effect (1.33%). The maximum adsorption capacity reached 174.1 mg/g, surpassing the performance of several comparable biosorbents reported in the literature. Overall, the findings demonstrate that Asplenium scolopendrium (hart’s-tongue fern) leaves represent an inexpensive, sustainable, and efficient material for eliminating methylene blue from aqueous solutions. Full article

The coexistence of emulsified oil, dissolved organics, and heavy metal ions in industrial oily wastewater makes one-step treatment highly challenging. Herein, an organic-inorganic co-modified PVDF composite membrane (MTSP) was fabricated via nonsolvent-induced phase separation, with tea polyphenols, SiO₂, and fibrous MXene synergistically incorporated. The resulting membrane exhibited a superhydrophilic/underwater oleophobic surface, with a water contact angle of 1° and an underwater oil contact angle of ~136°, owing to the optimized surface chemistry and hierarchical pore structure. As a result, the MTSP membrane effectively suppressed oil fouling while enabling rapid water transport. At 0.1 bar, the optimized membrane delivered an oil/water separation efficiency of ~99.5% and a high flux of 2420–2670 L·m⁻²·h⁻¹, while maintaining >99% separation efficiency for various emulsified oils, including kerosene, edible oil, n-hexane, and 1,2-dichloroethane. It also showed excellent recyclability and chemical stability, retaining >98–99% efficiency after five cycles and after 24 h exposure to pH 1 and pH 12 conditions. Notably, for complex simulated wastewater containing emulsified kerosene, phenol, and Fe³⁺, Cu²⁺, Zn²⁺, and Cd²⁺, the membrane maintained ~99% oil/water separation efficiency and simultaneously removed ~79% of phenol and 70–86% of heavy metal ions in a single filtration process. The superior performance is attributed to the synergistic effects of the superhydrophilic/underwater-oleophobic membrane surface, hierarchical transport channels enabling rapid water permeation, and multifunctional sites that adsorb/coordinate dissolved pollutants. This work provides a simple, scalable design strategy for PVDF-based membranes that integrate high-flux separation, antifouling performance, and multi-pollutant remediation for the treatment of complex oily wastewater. Full article

With the continuous promotion of the dual carbon target, effective control of high-concentration dust pollutants in industrial sites is of great value for the healthy creation of healthy industrial environments and efficient energy utilization. In this study, we used the spraying method to improve and prepare the dust removal material, polyphenylene sulfide (PPS) fiber filter material, and test the filtration performance, resistance characteristics, and dust-cleaning effect of the improved rGO-PPS material. The results showed that, compared with PPS filter material, rGO-PPS material significantly improved particle filtration efficiency, with a filtration efficiency 0.058–19.417% higher in the particle size range of 0.265–5.75 μm. The higher the spraying concentration of the composite filter material, the higher the filtration efficiency at the same particle size. The comprehensive filtration performance of rGO-PPS composite filter material with a concentration of 3 g/L was better, as it better met the requirements of “high efficiency and low resistance”. With an increase in dust load, the filtration resistance of the filter material showed a continuous upward trend. The dust peeling rate increased with an increase in blowback wind speed. When the blowback wind speed reached 0.3 m/s, the dust-cleaning effect of the filter material tended to stabilize. Under this condition, the dust peeling rate of PPS filter material was 61.58%, and the dust peeling rate of 3 g/L rGO-PPS composite filter material reached 74.52%. These research results provide an experimental basis and technical support for the development and engineering application of high-efficiency purification filter materials for industrial multi-source pollutants. Full article

Background: Cephalosporins, widely used β-lactam antibiotics, are becoming significant environmental pollutants, primarily due to their high use and persistence. They are released into the environment mainly through wastewater treatment plants, agricultural runoff, and hospital discharge, with particularly high concentrations recorded in effluents. Conventional wastewater treatment methods have inadequate removal efficiency, while advanced treatments, such as ozonation, activated carbon adsorption, and advanced oxidation processes, although more efficient, may produce toxic by-products. Recent studies emphasize the importance of improved detection and monitoring techniques and advocate for stricter effluent regulations. Despite growing research attention, important knowledge gaps remain, including limited long-term field monitoring, insufficient data on environmentally realistic exposure scenarios, and incomplete assessment of transformation-product toxicity. Methods: The search strategy used the SCOPUS and PUBMED databases with the keywords “cephalosporin” AND “aquatic environment”, resulting in 341 records. After applying predefined inclusion and exclusion criteria, 110 peer-reviewed English-language studies meeting predefined thematic inclusion criteria and relevant to the occurrence, environmental fate, ecotoxicological effects, antimicrobial resistance, and removal of cephalosporins in aquatic environments were included in the narrative synthesis. Results: The literature on cephalosporins in aquatic environments has expanded significantly from 1978 to 2025, prompted by concerns about pharmaceutical contamination and antibiotic resistance. Studies from 2016 to 2025 used advanced and multidisciplinary monitoring techniques, revealed key pollution sources such as wastewater treatment plants and hospitals, and correlated antibiotic residues with resistance genes, highlighting the need for continued monitoring and mitigation efforts. Ecotoxicological and fate studies further indicate that transformation processes may generate products with altered or increased toxicity, complicating environmental risk assessment. Conclusions: The literature shows increasing attention to cephalosporins in aquatic environments, reporting associations with antimicrobial resistance and adverse effects on aquatic organisms, including potential toxicity from transformation products. This review highlights the need for integrated monitoring, standardized toxicity assessment, and improved treatment strategies within a One Health framework. Full article

Landfills are complex repositories where macroplastics degrade into MPs. This review examines mechanical, chemical, and biological pathways of plastic fragmentation, as well as the occurrence, characteristics, and removal efficiency of MPs in landfill leachate. We also explore the landfill plastisphere from the perspective of this complex matrix, considering how plastic surfaces and microbial life may potentially converge to form a key biogeochemical interface that could influence carbon and nitrogen transformations The plastisphere’s complex surface structure drives microbial differentiation. Given its established links to GHG production in soil and water, we propose it likely represents a key contributor to GHG emissions in the more complex landfill environment. To bridge this conceptual gap, we review a mathematical scaffolding encompassing biofilm growth, polymer degradation kinetics, and gas flux, which can as a theoretical baseline requiring future in situ parameterization to evaluate plastisphere-driven biogeochemical interactions. Building on recent advances in monitoring and remote sensing technologies, including IOT networks, UAV imagery, and AI analysis, we outline a low-carbon landfill framework designed to optimize operational controls. This framework is described to simultaneously mitigate MP release and reduce GHG emissions, lowering carbon footprints. Amid surging plastic pollutants, this review underscores the necessity of holistic, integrated mitigation strategies. Full article

A discrete Hartley transform (DHT)-based orthogonal frequency division multiplexing (OFDM) scheme is investigated for intensity modulation/direct detection (IM/DD) visible light communication (VLC) systems, where transmitted signals are required to be real-valued and non-negative. To address this constraint, a practical unipolar transmission framework with corresponding bipolar reconstruction is developed. By exploiting the real-valued and self-inverse properties of the DHT, the proposed scheme removes the need for Hermitian symmetry and enables full utilization of available subcarriers. Under equal-bandwidth conditions, this results in an approximately 50% reduction in computational complexity compared with conventional DCO-OFDM and ACO-OFDM schemes. Theoretical analysis and numerical results further show that the proposed approach achieves comparable bit error rate (BER) performance while exhibiting improved spectral confinement, as reflected by reduced out-of-band sidelobes under identical filtering conditions. In addition, it maintains spectral efficiency equivalent to DCO-OFDM under the same bandwidth constraint. These advantages are achieved at the cost of restricting subcarrier modulation to real-valued constellations, which may reduce flexibility in frequency-selective channels. Overall, these findings support DHT-OFDM as a low-complexity, spectrally confined multicarrier waveform for IM/DD VLC systems, particularly in scenarios where efficient spectrum utilization and reduced adjacent-channel interference are required. Full article

Urban stormwater runoff often contains toxic metals that threaten aquatic environments. Meanwhile, the large quantities of drinking water treatment residuals (DWTRs) generated worldwide offer opportunities for sustainable reuse as pollutant removal materials. In this study, a manganese sand-modified drinking water treatment residual particle (RDP-M) was prepared from DWTRs and manganese sand for Pb(II) removal from water. Characterization by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) showed that RDP-M had a rough surface morphology and abundant oxygen-containing functional groups, which provided adsorption sites. Batch experiments showed that the maximum Pb(II) adsorption capacity of RDP-M reached 2.79 mg g⁻¹ at 298 K and pH 7.0, which was about 48% higher than that of the unmodified particles (RDP). The adsorption process followed the pseudo-second-order kinetic model and the Langmuir isotherm model, indicating a chemisorption-dominated process. Thermodynamic analysis further showed that the process was spontaneous and exothermic. RDP-M maintained stable Pb(II) removal over a wide pH range, showed low sensitivity to coexisting ions, and retained high efficiency during repeated use. These results demonstrate that RDP-M has potential as a sustainable granular material for stormwater treatment and waste resource valorization. Full article

Leaching carbon residue (LCR) is a carbonaceous solid waste generated during the hydrometallurgical recycling of spent lithium-ion batteries. Although its high graphite content offers substantial potential for resource recovery, the residual heavy metals and fluorides present in LCR pose considerable environmental risks. Currently, LCR has not garnered sufficient attention within the industry, and the lack of recycling technologies suitable for large-scale disposal results in resource wastage and environmental pollution. To address these challenges, this study proposes an innovative strategy based on the concept of multi-field synergistic enhancement. The proposed approach involves recovering and regenerating graphite (RG) from LCR via low-temperature molten salt roasting assisted by high-pressure and mechanical activation. A combination of advanced characterization techniques was employed to compare the physicochemical properties of RG and commercial graphite (CG) and to systematically evaluate the technical feasibility of using regenerated graphite as an anode material for lithium-ion batteries. The results demonstrate that, under optimized molten salt roasting and aqueous leaching conditions, the carbon content of RG reaches 99.94 wt%, indicating the efficient removal of non-carbon impurities from the graphite matrix. Compared to CG, RG retains a typical layered structure; however, a lower carbon content (99.94 wt%) and poorer structural order (I_D/I_G = 0.30) are observed. In terms of electrochemical performance, RG delivers a discharge specific capacity of 394.64 mAh/g during the first cycle and exhibits excellent cycling stability, with a capacity retention of 86.50% after 100 cycles. This electrochemical performance is comparable to that of commercial graphite. The proposed multi-field-assisted low-temperature molten salt roasting technique enables the efficient recovery of high-value graphite resources from LCR, establishing a full-lifecycle recycling strategy tailored for lithium-ion battery applications. Full article

The persistence of per- and polyfluoroalkyl substances (PFASs) in aquatic environments requires efficient and sustainable treatment technologies. In this study, the electrochemical degradation of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) was investigated using a grid-shaped Ti₄O₇ Magnéli-phase anode under electro-oxidation (EO) and electro-oxidation coupled with electro-Fenton (EO-EF) conditions. Structural characterization confirmed the predominance of Ti₄O₇ in the electrode material. At an initial concentration of 2 ppm, PFOS was rapidly and almost completely removed under both EO and EO-EF, whereas PFOA exhibited slower degradation kinetics, identifying it as the kinetically limiting compound. Coupling EO with electro-Fenton mainly enhanced the degradation kinetics, particularly for PFOA, while final removal efficiencies remained comparable. The influence of initial concentration was further examined, showing that lowering the PFOA concentration to 0.2 ppm, representative of environmentally relevant levels, enabled nearly complete removal within 300 min. Fluoride ion monitoring under optimized EO-EF conditions confirmed partial defluorination, demonstrating that PFOA removal is accompanied by C-F bond cleavage. These findings highlight the respective roles of EO and EO-EF processes and support the potential of Ti₄O₇-based anodes for energy-competitive PFAS remediation. Full article

To solve the problems of poor weld formation, difficult slag removal, and inferior joint microstructure and hardness in conventional narrow-gap submerged arc welding (NG-SAW), a swing arc NG-SAW process assisted by pre-embedding cold wires was proposed. Synergistically optimizing the welding energy parameters and additional cold wires ensured sound weld formation and enhanced slag detachability, while the efficiency of multilayer welding was improved by reducing the number of weld layers by 33.3%. The slag adhesion mechanism is clarified as follows: a high welding heat input facilitates elemental diffusion at the weld–slag interface, leading to the formation of a continuous and thick interlayer composed of (Fe,Mn)O and MgO-Al₂O₃-CaO phases. This interlayer strengthens the chemical bonding between slag and weld, thereby impeding slag removal. Microstructure evolution analysis of the multilayer welded joint revealed that the variable-angle design increases the groove volume and, combined with the heat-absorbing effect of the additional wires, accelerates molten pool cooling, thereby refining grains in both the weld metal zone and reheat-affected zone. Meanwhile, the tempering exerted by the heat-affected zone (HAZ) of the subsequent weld layer on the previous layer is attenuated. This promotes the gradual transformation of hard-brittle lath martensite in the coarse-grained heat-affected zone (CGHAZ) of the bottom layer into tougher tempered martensite/bainite in the CGHAZ of the upper layers. As a result, the hardness uniformity within the HAZ, the critical weak region of the joint, was enhanced by 54%, enabling synchronous improvement in microstructural homogeneity, hardness distribution, and overall welding efficiency. Full article

The load of the elastic tooth drum-type pepper harvester is a key parameter affecting harvesting efficiency and quality. Real-time analysis and prediction of drum load are crucial for stabilizing harvester operation and optimizing performance. Existing research focuses on either machine vision-based image analysis, which is difficult to collect in the field, or parameter-mapping methods, which suffer from time lag. This study proposes a GARCH-KPCA-ATLSTM method for load prediction, combining the generalized autoregressive conditional heteroskedasticity (GARCH) model, kernel principal component analysis (KPCA), and attention-enhanced long short-term memory (ATLSTM). EMD is first applied to denoise and reconstruct the load signal, removing mechanical vibration and other interferences. Conditional heteroskedasticity is confirmed, and the GARCH series (one symmetric and three asymmetric models) is introduced to extract fluctuation features. KPCA reduces dimensionality, removing redundant information and saving 2.91 s in computation while slightly improving accuracy. Additive attention in LSTM emphasizes critical information, enhancing learning of nonlinear relationships and further improving prediction. Comparative experiments demonstrate the model’s reliability. The method achieves RMSE = 0.911, MAE = 0.682, MBE = −0.025, MAPE = 1.147%, R² = 0.968, with a runtime of 2.023 s, confirming high accuracy and stability. This study provides a theoretical and technical foundation for real-time load prediction of pepper harvesters. Full article

In this study, new types of eutectic solvents (ESs) are tested for their ability to remove the eight most common bisphenols (BPA, BPB, BPC, BPE, BPF, BPG, BPS, BPAP), which are environmentally monitored substances, from aqueous matrices. A total of 18 ESs based on hydrophobic organic acids, such as capric, caprylic, lauric, and myristic acids, and terpenes, such as DL-menthol, terpineol, linalool, and geraniol, are prepared and mixed in various molar ratios. The highest extraction yield for all types of BPs is achieved with a binary mixture of geraniol:caprylic acid prepared in a molar ratio of 1:1. This ES can be used repeatedly for five consecutive cycles achieving almost 100% recovery for BPB, BPC, BPG, and BPAP, while for BPA, BPE, and BPF, the yield drops to 97% and for BPS to 90%. The efficiency of ES extraction is verified using HPLC-MS/MS to determine the BPs in the aqueous phase. This is performed at a pentafluorophenylpropyl stationary phase with LOQs ranging from 0.24 to 29.1 ng/mL. The applicability of this HPLC-MS/MS method was demonstrated by monitoring the occurrence of BPs in thermal paper and other industrial samples. Full article

Recirculating aquaculture systems (RASs) improve water-use efficiency in fish production but generate nutrient-rich effluents requiring management. Integrating aquatic biomass cultivation into RASs offers a promising approach to nutrient recovery, CO₂ utilization, and biomass production. This study evaluates the technical and economic feasibility of integrating Wolffia globosa cultivation with RASs through process simulation and techno-economic analysis (TEA). A pilot-scale system in Thailand was modeled using SuperPro Designer, comparing static and suspended aeration cultivation. The suspended configuration required only ~10–12 m² for 28.80 m³, whereas static cultivation required 131 m² for 32.80 m³, corresponding to about a 12-fold reduction in land area. The suspended system achieved higher annual biomass production (1056 kg dry weight (DW) yr⁻¹) than the static system (690 kg DW yr⁻¹), corresponding to CO₂ fixation of ~1.50 and ~0.98 t CO₂ yr⁻¹, respectively. The static system achieved higher nutrient removal efficiencies (97% N and 99.66% P), while the suspended system showed lower removal (64% N and 65.30% P) but higher productivity. Economic analysis confirmed feasibility, with the suspended system achieving higher return on investment (17.56% vs. 12.89%) and a shorter payback period (5.70 vs. 7.76 years). These results demonstrate the potential of RAS–Wolffia integration as a circular approach for resource recovery and sustainable aquaculture. Full article

The non-thermal plasma (NTP) process is a promising advanced oxidation process (AOP) for removing non-biodegradable organics from wastewater, owing to the efficient formation of reactive chemicals. Despite its effective oxidizing capability, the decomposition mechanism of organic pollutants is not well understood. This study evaluates NTP for two representative sulfonamides (SMZ and STZ) and reports on (i) time-resolved removal to the method detection limit, (ii) transformation mapping using LC-ESI/MS/MS, which confirmed previously proposed hydroxylation and bond-cleavage pathways and further identified additional hydroxylated intermediates formed on the thiazole and benzene rings under NTP conditions, and (iii) energy evaluation through energy per order (EEO) within a single, reproducible operating window. The EEO values for SMZ and STZ degradation via NTP were calculated at 22.4 and 7.5 kWh/m³/order, respectively. These values are up to 37- and 118-fold lower than those reported for comparable AOPs, quantitatively confirming that the proposed NTP process achieves superior energy efficiency for sulfonamide degradation. Degradation is primarily attributed to reactive oxygen species (ROS) generated by plasma, which initiate the breakdown of the antibiotic structure. Overall, this study demonstrates that NTP is a highly effective AOP for driving the rapid primary degradation and intermediate structural transformation of recalcitrant sulfonamide antibiotics. Full article

Sulfate-reducing ammonium oxidation (SRAO) is an emerging anaerobic autotrophic nitrogen removal process that combines ammonium oxidation with sulfate reduction. However, it faces some challenges, such as the slow growth of autotrophic microorganisms, weak synergistic interaction between different microorganisms, and poor substrate transfer capability. Herein, graphene oxide (GO) was added to a lab-scale bioreactor to promote SRAO reaction, and its effect on nitrogen removal was systematically investigated. The results demonstrated that GO served not only microbial carriers but also electron shuttles, which were conducive to microbial spatial distribution and better electron transfer, improving the sulfur cycle-driven multi-pathway nitrogen removal performance. The addition of 50 mg/L GO not only enhanced the SRAO activity and increased the ammonium removal efficiency by 24.7%, but also reduced the effluent nitrite concentration and promoted nitrogen production. After reaction, the main functional groups on the surface of GO had been changed, and the composite aggregates of microorganisms were formed. Mass balance analysis revealed that SRAO was the dominant pathway, while Anammox and sulfur-autotrophic denitrification (SADN) played complementary roles. Moreover, after adding GO, the relative abundances of Desulfosarcinaceae and Bacillus, which were functional microorganisms in the SRAO reaction, were increased by 35.7% and 58.5%, respectively. This study will provide an in-depth understanding of the mechanisms for nitrogen removal in the SRAO bioreactor. Full article