The boosting development of artificial intelligence (AI) is contributing to rapid exponential surge of computing power demand, which results in the concerns on the increased energy consumption and carbon emission. To highlight the environmental impact of AI, a quantified analysis on the carbon emission associated with AI systems was conducted in this study, with the hope of offering guidelines for police maker to setup emission limits or studies interested in this issue and beyond. It has been discovered that both industry and academia play pivotal roles in driving AI development forward. The carbon emissions from 79 prominent AI systems released between 2020 and 2024 were quantified. The projected total carbon footprint from the AI systems in the top 20 of carbon emissions could reach up to 102.6 Mt of CO2 equivalent per year. This could potentially have a substantial impact on the environmental market, exceeding $10 billion annually, especially considering potential carbon penalties in the near future. Hence, it is appealed to take proactive measures to develop quantitative analysis methodologies and establish appropriate standards for measuring carbon emissions associated with AI systems. Emission cap is also crucial to drive the industry to adopt more environmentally friendly practices and technologies, in order to build a more sustainable future for AI.
● A colorimetric nanobiosensor with one-step was developed for Pb2+ detection. ● An A-C mismatched DNAzyme was designed to improve the sensitivity. ● The detection limit of 8.6 nmol/L was achieved for Pb2+. ● Satisfactory recoveries were achieved in various real water samples. ● An entire detection time was less than 30 min.
Facile and ultrasensitive detection of Pb2+ in water for remote or resource-limited environments remains challenging. DNAzyme-based colorimetric nanobiosensors have been extensively studied to regulate the assembly of functionalized gold nanoparticles (AuNPs). However, these nanobiosensors have been criticized for their low sensitivity owing to the difficulty of dissociating DNAzyme embedded in AuNP aggregates. To address this issue, we rationally designed a DNAzyme by introducing an adenine-cytosine (A-C) mismatch to strengthen the disassembly of DNAzyme-linked nanostructures. As proof of concept, a “turn on” colorimetric nanobiosensor integrated with mismatched DNAzyme and functionalized AuNPs was first developed for Pb2+ detection. Under the optimal detection conditions, the obtained typical calibration curve shows a detection limit of 8.6 nmol/L, with an approximately 11-fold sensitivity improvement in Pb2+ detection compared with unmismatched DNAzyme, and a linear response range from 10 to 300 nmol/L. This nanobiosensor demonstrated robust selectivity and satisfactory recovery rates between 86.5% and 106.4% for Pb2+ in spiked environmental water samples. Additionally, the detection process is user-friendly and can be completed within 30 min, requiring only a simple water sample addition step. Considering the extensive applications of DNAzyme in conjunction with nanoparticles, this study provides a valuable reference for designing other DNAzyme-powered nanoparticle assemblies in biosensing systems.
● Efficient removal of COD and nitrogen was achieved in the AnMBR–NF–PDA system. ● Precise COD/NO3−–N control was achieved by adjusting the raw water proportion. ● The presence of filamentous bacteria was conducive to sludge granulation in PDA. ● AnAOB and filamentous bacteria achieved a good cross-feeding relationship.
In this study, an anaerobic membrane bioreactor coupled with a complete nitrification and partial denitrification–anammox process (AnMBR–NF–PDA) was developed to efficiently remove both chemical oxygen demand (COD) and nitrogen. Precise control of raw water ratios was utilized to adjust the ratio of COD/NO3−–N, resulting in maximum nitrogen removal efficiency of 90.14% at a ratio of 3.44. Initially, specific anammox activity (SAA) increased with the proportion of raw water, peaking at 17.83 mg-N/(g-VSS∙d) in stage II before decreasing. This variation was attributed to the significant presence of filamentous bacteria, especially “Acinetobacter” (13.58%–31.59%), which facilitated nitrite generation, supporting the nitrous oxide hypothesis in partial denitrification processes and enabling cross-feeding with AnAOB. Additionally, the average particle size of granular sludge increased from 300 to 528 µm under the influence of filamentous bacteria. Metagenomic analysis revealed an upsurge in genes associated with partial denitrification (NarG and NapA) as the COD/NO3–N ratio rose. The abundance of genes closely correlated with anammox (Hzs and Hdh) peaked during stage II, indicating the beneficial role of filamentous bacteria in the stable conversion of nitrite in PDA system. This study offers valuable insights into optimizing the synergistic metabolism and granulation processes involving filamentous bacteria and AnAOB, thereby laying the groundwork for the practical application of AnMBR coupled with anammox processes in wastewater treatment.
● Two mixing modes of hydrothermal humification of corn stalk and sludge were set. ● N-rich hydrothermal humic acid (HHA) from corn stalk and sludge was produced. ● Behavior of hydrothermal humification of corn stalk and sludge was revealed. ● Humification of corn stalk and sludge enhanced N content in HHA. ● HHA derived from corn stalk and sludge has no heavy metal risk.
The high organic carbon content in corn stalks (CS) and the rich nitrogen resources in sewage sludge (SS) render them ideal for the hydrothermal production of nitrogen-enriched hydrothermal humic acid (HHA). This study conducted co-hydrothermal humification experiments using varying ratios of CS to SS under two distinct mixing modes: 1) co-hydrothermal carbonization of CS and SS, followed by alkaline hydrothermal humification to yield HHA, and 2) mixing CS-derived hydrochar with SS, followed by alkaline hydrothermal humification to yield HHA. The results indicated no significant difference in HHA yield between the modes when using equivalent raw material ratios. Importantly, the HHA produced did not pose a heavy metal risk. However, HHA from mode (1) had nearly double the nitrogen content compared to mode (2) and contained more valuable metal elements. The study confirmed that while co-hydrothermal humification of CS and SS did not significantly enhance HHA yield, it did markedly increase nitrogen content. Furthermore, HHA yield decreased with increasing SS content in the raw materials, likely due to SS's high ash content (52.4 wt%). In contrast, the nitrogen content in HHA increased with higher SS content, rising from 2.0 wt% to 3.8 wt% in mode (1) and from 1.1 wt% to 2.3 wt% in mode (2). Upon comprehensive analysis of both modes, the study suggests that mode (1) is more promising for engineering applications, as it facilitates the efficient disposal of a larger amount of SS.
● CeO2 was uniformly coated on the surface of carbon fibers with fibrous structure. ● 1O2 are generated on the active sites of Vo and C=O for CeO2@CF. ● A large number of electron-rich oxygen vacancies formation inside CeO2@CF. ● Complete degradation of 50 mg/L 2,4-DCP was realized with good mineralization. ● It shows good purification ability for actual coking wastewater.
CeO2 was uniformly coated onto the surface of carbon fibers (CF) and the resulting CeO2@CF was employed for the activation of peroxymonosulfate (PMS) to degrade 2,4-Dichlorophenol (2,4-DCP). Under the initial conditions of a PMS concentration of 10 mmol/L, pH range of 3 to 9 and a CeO2@CF mass concentration of 0.1 g/L, the system achieved complete degradation of 50 mg/L of 2,4-DCP with high mineralization efficiency within 60 min. Additionally, the CeO2@CF/PMS system showed high efficiency in the presence of coexisted anions (HCO3−, CO32−, SO42−, Cl−) and exhibited excellent purification capability for actual coking wastewater. Combined with characterization analyses (SEM-EDS, XRD, Raman, XPS, and EPR), degradation experiments and radical quenching experiments, the physicochemical properties of the prepared catalyst and the 2,4-DCP degradation mechanism were explored. Results revealed that CeO2 was uniformly coated on the CF surface, maintaining a regular framework structure. During this process, Ce4+ in CeO2 was reduced to Ce3+, resulting in numerous electron-rich oxygen vacancies forming inside CeO2@CF. Furthermore, the CeO2 coating increased the amount of oxygen-containing groups (C=O) on the surface of CF and graphite defects. In the CeO2@CF/PMS system, •O2− and 1O2 were generated at the active sites of the oxygen vacancies (Vo) and C=O with 1O2 dominated non-free radical pathway and played a notable role in the 2,4-DCP degradation process.
● BMOFs offer high conductivity, active sites, and photo-responsiveness. ● BMOFs have adjustable active sites for high photocatalytic activity. ● Various tailoring strategies for improving BMOFs properties were summarized. ● Advances in BMOFs materials for photocatalytic applications are discussed. ● BMOFs are integrated to form Z and S-scheme heterojunctions.
Photocatalysis contributes significantly to global economic development and has promising environment application like degradation of organic contamination and energy production. The initiatives are concentrated on accelerating the reaction rates and designing novel photocatalysts for improving the ability and enhance the selectivity toward specific products. Recently, bimetallic nanoparticles (NP)/metal-organic frameworks (BMOFs), gained broader interests in heterogeneous catalysis due to their unique photocatalytic properties. Coupling of bimetallic nanoparticles with metal-organic frameworks has found to be a highly effective strategy to improve the photocatalytic activity and broaden the reaction scope. In addition, BMOFs have been found to have exceptional capabilities in breaking down organic pollutants, reducing heavy metals and producing energy. These remarkable abilities are believed to be a result of the combined effects of the bimetallic centers. This review summarizes and analyses the recent advancements in BMOFs based materials especially heterojunctions for degradation of organic pollutants and also in energy production. Different synthesis techniques of designing BMOFs composites are highlighted in this study. The underlying mechanism synergistically enhanced performance in heterogeneous catalysis is thoroughly examined. This review also explores the challenges and possible future pathways in photocatalysis using BMOFs. There are several important challenges that need to be addressed in order to improve the durability of BMOFs in real-world conditions, optimize the synthesis process for industrial applications and gain a deeper understanding of the complicated structures that influence their photocatalytic processes.
● Animal breeding facilities suffer from significant microbial aerosol contamination. ● Aerosol concentrations are higher in poultry houses than in other animal housing. ● The dominant bacterial and fungal species varied among different animal houses. ● ARGs pose a major challenge to disease prevention efforts in animal settings. ● Microbial aerosols mainly cause damage through cytokine storms and oxidative stress.
Livestock and poultry breeding environments suffer from serious microbial aerosol pollution, posing a significant challenge to maintaining healthy animal rearing. This study reviewed the sources, pollution status, hazards, pathogenic mechanisms, and mitigation measures of microbial aerosols in livestock and poultry breeding settings, based on research conducted over the past two decades. Notably, the study analyzed the distribution characteristics of aerosol components in various animal houses, with a focus on identifying the main factors affecting these characteristics and the molecular mechanisms by which they damage the animal immune system. Quantitative analysis revealed varying concentrations of bacterial and fungal aerosols in different animal houses, with poultry houses often exhibiting higher concentrations. The dominant bacterial and fungal species varied across different animal houses, emphasizing the complex composition of microbial aerosols. Furthermore, antibiotic-resistant bacteria and genes, particularly those resistant to tetracycline, are prevalent in these environments, challenging disease prevention and control efforts. Thus, the infection source must be controlled through isolation measures and proper waste management. Proper disinfectant use, responsible antibiotic stewardship, biosecurity measures, and alternative disease prevention strategies should be implemented. Future research should focus on developing monitoring technologies for pathogenic microorganisms, implementing purification technologies, and investigating the immune-damaging mechanisms of microbial aerosols. By addressing these areas, we can further understand microbial aerosols in livestock and poultry environments and develop effective strategies to mitigate their harmful effects. This review contributes to the sustainable development of animal farming to ensure the health and welfare of animals.
● The highest syngas yield of 10.9 mol/kg with 44.7% H2 concentration was achieved. ● The distribution of heavy metals with/without alkaline additives was investigated. ● Risk Assessment Code of heavy metals after SCWG reduced to less than 1%. ● Possible reaction pathways of heavy metals during SCWG of sludge were proposed.
The rising production of sewage sludge, characterized by high organic content and excessive heavy metals, necessitates an effective treatment method. This study investigated the production of syngas and the migration and transformation behavior of heavy metals such as Zn, Ni, Cr, Cu, and As during supercritical water gasification (SCWG) of sewage sludge. The experiments were conducted without or with alkaline additives at temperatures between 380 to 420 °C and retention time from 15 to 60 min. The results revealed that the highest syngas yield reached 10.9 mol/kg with an H2 concentration of 44.7% at 420 °C and 60 min. In this process, heavy metals were effectively immobilized and converted into a more stable form, whereas higher temperatures and longer retention time enhanced this effect. The introduction of alkaline additives (NaOH, KOH, Ca(OH)2, Na2CO3, and K2CO3) led to the redistribution of heavy metals, further promoting the stabilization of Zn, Cr, and Cu. An environmental risk assessment showed that SCWG could significantly lower the risk associated with heavy metals to a low or negligible level.
● Cyanex 272-PVDF membranes efficiently extract Co(II). ● FTIR, SEM, and EDX confirmed homogeneous blending and enlarged pore size. ● Optimal Co(II)/Ni(II) separation factor of 209.5 was achieved at pH 6.8 and 75 °C. ● Membranes retained 98% adsorption capacity over 20 recycling cycles. ● A cost-effective, eco-friendly alternative to solvent extraction was presented.
Liquid-liquid solvent extraction, commonly used for high purity Co(II) extraction, suffers from drawbacks such as environmental pollution and high cost. To overcome these challenges, a novel Cyanex 272 (bis(2,4,4-trimethyl pentyl)phosphinic acid, HCyanex) adsorptive membrane (CAM) was synthesized using the phase inversion method with varied Cyanex 272 loadings (0–52.5%) to extract Co(II) from cobalt-nickel mixed sulfate solution. Fourier transform infrared (FTIR) spectrometer, Scanning electron microscopy (SEM), and Energy dispersive X-ray spectroscopy (EDX) of as-prepared CAMs confirmed the successful and homogeneous blending of Cyanex 272 with poly(vinylidenefluoride) (PVDF), and increased pore sizes were observed with the addition of Cyanex 272. The highest Co (II) removal was achieved by the CAMs containing 33.2% weight percentage of Cyanex 272 to PVDF with a Langmuir sorption capacity of 1.42 mg/g. The extraction process for Co(II) and Ni(II) by CAMs was sensitive to pH and temperature, with an optimal separation factor of 209.5 at pH 6.8 and 75 °C. The adsorption process is endothermic. Additionally, the membrane exhibited excellent stability and durability, maintaining around 98% adsorption capacity after 20 cycles in the recycling process. These findings suggest that the as-prepared CAMs are a promising technology for the separation of Co(II) from Ni(II) in the recycling process of lithium-ion batteries.
● MNBs can enhance other water purification methods. ● MNB technology is its ability to eliminate pathogens in water and wastewater sources. ● The stability or MNBs and oxygen transfer depend on the size of bubbles. ● Ozone-MNBs provide an efficient and cost-effective approach to wastewater treatment.
The global scarcity of drinking water is an emerging problem associated with increasing pollution with many chemicals from industry and rapid microbial growth in aquatic systems. Despite the wide availability of conventional water and wastewater treatment methods, many limitations and challenges exist to overcome. Applying technology based on microbubbles (MBs) and nano-bubbles (NBs) offers ecological, fast, and cost-effective water treatment. All due to the high stability and long lifetime of the bubbles in the water, high gas transfer efficiency, free radical generation capacity, and large specific surface areas with interface potential of generated bubbles. MBs and NBs-based technology are attractive solutions in various application areas to improve existing water and wastewater treatment processes including industrial processes. In this paper, recent progress in NBs and MBs technology in water purification and wastewater treatment along with fundamentals, application, challenges, and future research were comperhensively discussed.
● A total of 3714 studies on ARB and ARGs removal techniques over 26 years were reviewed. ● Adsorption has been studied mostly for ARB and ARGs degradation, and adsorbents are important. ● Nanomaterials and biomodified materials exhibit great potential. ● Combined techniques to remove ARB and ARGs are proposed for the future.
The spread of antibiotic resistance is a global threat, causing elevated death rates and economic costs. A growing number of studies have focused on the removal of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in environmental settings. However, summaries and reviews of removal techniques are limited. This study examined publications on ARB and ARGs removal from 1998 to 2023 through a bibliometric approach based on the Web of Science database. Research progress during the past 26 years was analyzed by collecting annual publications, countries, journals and keywords. The number of articles related to the removal of ARB and ARGs has increased annually. The main types of ARB and ARGs, their environmental milieus and the most commonly studied removal techniques were summarized by keyword clustering. The results revealed that tetracycline- and sulfonamide-resistant bacteria are the ARB of greatest concern; that sul1, sul2, and tetA are the most frequently studied ARGs; and that municipal sewage and drinking water are the most studied ARB and ARGs transmission sites. For treatment techniques, adsorption technology is the most widely studied, and the selection of adsorption materials is particularly important, with nanomaterials and biomodified materials having great prospects for development. The combination of membrane filtration with advanced oxidation treatment or biodegradation technology is the most promising technology in this field. Our findings can inform future efforts to further reduce the distribution risks of antibiotic resistance and improve removal techniques.
