Heavy Pollution Research Articles

Impact of energy saving and emission reduction policy: Empirical evidence from regional and local business in China

AbstractReducing energy intensity (EI) is essential to promoting sustainable development. The “National Energy Saving and Emission Reduction Comprehensive Demonstration Fiscal Policy” (ESERP) is the green fiscal policy adopted by China in an effort to maximize energy use and promote sustainable development. The paper analyzes the influence of ESERP on EI from regional and business standpoint. The results indicate that ESERP is effective in reducing EI, especially when it is implemented in noneastern, low administrative, and high urbanization cities. This policy effect is realized by promoting green technology innovation and enhancing industrial structural upgrading. However, ESERP enhances EI of neighboring areas around the pilot cities, especially within 200 to 400 km of the perimeter. Meanwhile, the co‐implementation of ESERP and smart city pilot policies is beneficial in reducing EI. Additionally, business strategy analysis indicates that ESERP effectively reduces EI of firms, especially in private, technology‐intensive, asset‐intensive, and heavy polluting firms. This paper provides empirical experience for optimizing green fiscal policy and promoting sustainable business development, which has significant policy guidance value and business strategy significance.

Nanotechnology advancements in groundwater remediation: A comprehensive analysis of current research and future prospects

Groundwater contamination is a critical environmental issue with vital health implications. This review evaluates the advancements in nanotechnology for groundwater remediation, highlighting major findings and their relevance to Sustainable Development Goals (SDGs). Key findings include the superior adsorption capabilities of multi-walled carbon nanotubes functionalized with various groups for removing heavy metals and aromatic pollutants, outperforming traditional sorbents. The review also discusses the potential of nanomaterials like zero-valent iron nanoparticles for effective contaminant degradation. Despite promising results in the studies, challenges such as the movement and dispersion of engineered nanomaterials in porous media and the need for innovative delivery methods are identified. Furthermore, this review explores the environmental and health risks associated with the use of nanomaterials, emphasizing the need for risk assessments to ensure safe application. The novel delivery methods assessed, such as the use of groundwater circulation wells and the combination of nanoremediation with other techniques like bioremediation, demonstrate potential to enhance remediation efficiency. The integration of nanotechnology in groundwater remediation directly contributes to Clean Water and Sanitation by providing innovative solutions for the purification of water resources. Advanced nanomaterials not only improve contaminant removal efficiency but also promote sustainable water management practices. Additionally, the environmental benefits align with Life on Land, as the reduction of hazardous substances in groundwater protects terrestrial ecosystems and promotes biodiversity conservation. This review study aims to enhance understanding and identify future opportunities for nanotechnology in groundwater remediation. By addressing current challenges and proposing innovative solutions, this review underscores the importance of interdisciplinary research and collaboration in advancing sustainable development.

PROPIEDADES DINÁMICAS DE IMPACTO DE COMPUESTOS DE LODOS DE PAPEL DOPADOS CON OXICLORURO DE MAGNESIO

To address the heavy pollution caused by paper sludge, this study investigates a novel approach by incorporating paper sludge into magnesium oxychloride cement to develop a new type of concrete composite material. To achieve waste utilisation, cost savings and pollution reduction, the impact dynamics properties of the concrete specimens were conducted using an electromagnetically driven Hopkinson pressure bar, while a high-speed camera recorded the specimen destruction process, stress-strain curve, destruction morphology, deformation field, and evolution of energy consumption. Results show that as the paper sludge doping increases, the peak stress of the stress-strain curve and the energy consumption gradually increase. Increasing the voltage leads to a gradual rise in peak stress and energy consumption of the specimen. During the impact test, the transverse fissures gradually are developed in the test block, and as the impact stress increases, the fissures are widened until the specimen eventually being fractured. Moreover, the higher impact voltage and paper sludge content result in the increased specimen displacement and strain. It is expected that nearly 50% of paper sludge will be recycled every year by this method, which will save 10%-20% of raw materials. The conclusions obtained in this study provide a reference for the engineering application of the paper sludge concrete composites. Keywords: Paper sludge, Magnesium oxychloride, Digital image correlation, Energy consumption, Impact dynamic properties.

Fabrication of metal‐organic frameworks macro-structures for adsorption applications in water treatment: A review

Metal-organic frameworks (MOFs) are emerging porous organic–inorganic hybrid materials composed of metal centers/clusters and various organic ligands, which are widely used in water and wastewater treatment applications due to their large specific surface area, high porosity, tunable chemical properties and abundant active sites. However, pure MOFs powders have limitations such as poor recovery, blocked pipelines and secondary contamination in practical water treatment processes. Enabling the magnetization of MOFs or immobilizing MOFs as macroscopic MOFs materials offers new opportunities to improve solid–liquid separation performances of powdered MOFs. Besides, macroscopic MOFs materials with outstanding adsorption performance and mechanical properties by the combining of 3D particles and 2D nanosheets MOFs with other substrates are widely used for water treatment. This paper provides a comprehensive review of recent advancements in MOFs macro-structures. We firstly summarized the synthesis strategies of magnetic MOFs composites and various MOFs macro-structures such as hydrogels/aerogels, membranes, beads/spheres, others composites, etc. which can be constructed by various methods, including in-situ growth, solvothermal method, direct mixing, self-assembly, layer-by-layer growth, etc. Innovative preparation strategies to improve the mechanical properties of MOFs macro-structures were highlighted. Next the article discusses its application for adsorptive removal of various pollutants (i.e., dyes, heavy metal ions, oils and organic pollutants) from water. Finally, the challenges of macroscopic MOFs materials and their practical applications are presented, while future research directions to overcome these existing limitations are also pointed out.

Uncovering socio-economic driving forces of volatile organic compounds emissions in the Beijing-Tianjin-Hebei region of China

The Beijing-Tianjin-Hebei (BTH) region is an important urban agglomeration in northern China, which has experienced rapid economic growth and heavy air pollution such as volatile organic compounds (VOCs) emissions. It is therefore urgent to uncover the socio-economic driving forces of VOCs emissions so that the BTH region can move toward sustainable development. This study aims to fill this research gap by measuring the contributions of different socio-economic factors to VOCs emissions in the BTH region during 2008–2017 by using the generalized Divisia index method (GDIM). Our results show that energy consumption scale and economic scale are the two largest contributors to the increase of VOCs emissions, while emission intensity of output and emission intensity of energy are the two dominant drivers for preventing the increase of VOCs emissions in the BTH region. Other factors, such as population scale, per capita emission, per capita GDP, and energy intensity, have marginal effects on VOCs emissions. These findings provide valuable insights to those policy makers in the BTH region to prepare effective measures to mitigate their VOCs pollution by considering regional disparity.

Pollution level and distribution characteristics of heavy metals and microplastics in the soils from the Qionghai Lake Wetland, Southwest China

Urban wetlands are reported to be ideal habitats for accumulation of HMs and MPs. However, study on combined pollution of HMs and MPs in soil is rare in urban wetland environment. In this study, the characteristics of HMs and MPs in the soils of the Qionghai Lake wetland in southwest China were studied by using ICP–MS, and FTIR. The results showed that the average concentration of HMs in soil ranges from 0.84 to 552.75 (mg/kg). According to the EF and Igeo analysis results, Cd and Cr in the soil were significant enriched (EF=12.64) and moderately enriched (EF=2.09), and were at the moderate to heavy pollution level (Igeo = 2.83) and the unpolluted to moderate pollution level (Igeo = 0.23), and the other elements were at a low level. MPs are emerging micropollutants in the soil environment, and the abundance (pieces/g) of MPs in the soil was 3.90, 7.00, 3.10, 3.40, 14.80, and 1.10 at Stations M1, M2, M3, M4, M8, and M9, respectively, with an average of 5.55 ± 4.92. Films represented the main microplastic shape, accounting for 81.55 %, followed by fibers, accounting for 11.33 %. The proportion of MPs with a particle size of 0.1–0.5 mm is the highest. Black, blue, and green are the predominant colors found in MPs. Polyethylene (PE) and polypropylene (PP) were the main MP materials based on FTIR identification, accounting for 52.16 % and 42.31 % of the total MPs, respectively. The pollution load index (PLI) of MPs was 2.2, which is a level Ⅰ pollution. The research on HMs and MPs in urban wetland soil is still in its preliminary stage. Our aim is to offer a fresh perspective for evaluating the pollution status and risk associated with these two pollutants in urban wetland soil, while also providing a valuable reference for subsequent studies on wetland soil pollutants.

Exploring the missing link between top management teams' characteristics and environmental information disclosures of construction corporations

PurposeGiven the heavy pollution feature of the construction industry, construction corporations need to adopt an effective environmental governance strategy. The quality and quantity of environmental information disclosure (EID) implementation, as an essential part of a corporate environmental governance strategy, is impacted by the characteristics of the top management team (TMT). This paper aims to analyze the relationship between the demographic characteristics of the TMT (i.e. gender, age, tenure, educational level, and duality) and corporate EID.Design/methodology/approachUsing data from listed construction corporations generated between 2014 to 2018 in China, this study employs the Tobit regression model to test the research hypotheses. Also, this study applies a novel analytical approach, necessary condition analysis (NCA), to conduct a series of additional tests.FindingsThe results reveal that tenure and educational level are significantly and positively related to EID, while gender, age, and duality in the executive role are not significantly related to EID. When considering the TMT size as a moderator, the TMT age is positively related to the corporate EID, and the size of the TMT acts as a moderator to weaken the positive effect of the TMT age on the EID. The NCA results show that TMT gender, age, tenure, and educational level are necessary when the levels of EID exceed 40%.Originality/valueOur findings suggest that TMT characteristics have a relatively significant effect on corporate EID levels, which extends EID research to the construction industry. Corporate planners can endeavor to shape TMT characteristics to improve EID levels. The results of NCA provide insights into what TMT characteristics construction corporations need to satisfy in their pursuit of transparent EID, as well as the levels at which these characteristics are desired.

The Influence of Rural Ecological Environment Development by China's Industrialization Process

This article aims to solve the problem of heavy pollution load in rural ecological environment at present. This article elaborates on the relevant concepts and theories of rural industrialization and ecological environment protection, mainly using a combination of qualitative and quantitative methods to analyze the current situation of rural ecological environment pollution in the research area. The research results indicate that the current rural ecological environment pollution load in China is heavy and severe, especially the use of fertilizers, pesticides, agricultural plastic films, livestock and poultry breeding, rural life, and township enterprise production, which have caused varying degrees of harm to the regional rural ecological environment. Therefore, effective measures must be taken to achieve the organic combination of rural industrialization and ecological environment protection. This article provides guidance for promoting the optimization and upgrading of rural industrial structure, achieving a win-win situation of economic and ecological benefits.

Spatial and temporal differentiation and its driving factors of air quality in the economic circle of Shandong Province during 2013–2020

As the negative repercussions of environmental devastation, such as air quality decline and air pollution, become more apparent, environmental consciousness is growing across the world, forcing nations to take steps to mitigate the damage. China pledged to achieve air quality improvement goal to combat global environment issue, yet the spatial-temporal differentiation and its driving factors of environment-meteorology-economic index for air quality are not fully analysed. To promote regional collaborative control of air pollution and achieve sustainable urban development, spatial and temporal different and its driving factors of air quality in Shandong Province during 2013–2020. Results revealed that concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), particulate matter 2.5 (PM2.5), particulate matter 10 (PM10), and carbon monoxide (CO-95per) exhibited decreasing trend (SO2 concentrations decreasing 84 % and CO-95per concentrations decreasing 90 %). Air quality was improved from inland areas to coastal areas. Pollutant indicators of SO2, NO2, PM10, PM2.5, and CO-95per demonstrated significant positive correlation (P < 0.05). Air temperature and precipitation are significantly negatively correlated with concentrations of SO2, NO2, PM10, PM2.5, and CO-95per but significantly positively correlated with ozone (O3-8 h). SO2, NO2, PM2.5, PM10, CO-95per, and proportion of days with heavy pollution are strongly positively correlated with proportion of secondary industry but strongly negatively correlated with proportion of tertiary industry and volume of household waste. Except for O3-8 h, pollutant index of Provincial Capital Economic Circle (PCEC) and Southern Shandong Economic Circle (SSEC) has significant negative correlation (P < 0.05) with regional gross domestic product and investment in environmental protection; however, investment in environmental protection of Eastern Shandong Economic Circle (ESEC) has no significant correlation with air pollution index. There was significant negative correlation between vegetable sowing area and SSEC pollutant index. The relationship between pollution emission and investment in environmental protection has shifted from high pollution-low investment to low pollution-low investment in PCEC, ESEC and SSEC, and the inflection point was in 2020 for PCEC, 2019 for ESEC, and 2020 for SSEC. Those results provide empirical evidence and theoretical support for the improvement of regional air quality, aiming to achieve high-quality development. According to these findings, it has been found that meteorological elements, pollutant emission, socio-economic factors and agricultural data affect air quality. Those results could provide meaningful and significant supporting for synergistic regulation of diverse pollutants.

Utilizing machine learning to evaluate heavy metal pollution in the world's largest mangrove forest

The world's largest mangrove forest (Sundarbans) is facing an imminent threat from heavy metal pollution, posing grave ecological and human health risks. Developing an accurate predictive model for heavy metal content in this area has been challenging. In this study, we used machine learning techniques to model sediment pollution by heavy metals in this vital ecosystem. We collected 199 standardized sediment samples to predict the accumulation of eleven heavy metals using ten different machine learning algorithms. Among them, the extremely randomized tree model exhibited the best performance in predicting Fe (0.87), Cr (0.89), Zn (0.85), Ni (0.83), Cu (0.87), Co (0.62), As (0.68), and V (0.90), achieving notable R2 values. On the other hand, the random forest outperformed for predicting Cd (0.72) and Mn (0.91), whereas the decision tree model showed the best performance for Pb (0.73). The feature attribute analysis identified FeV, CrV, CuZn, CoMn, PbCd, and AsCd relationships resembled with correlation coefficients among them. Based on the established models, the prediction of the contamination factor of metals in sediments showed very high Cd contamination (CF ≥ 6). The Moran's I index for Cd, Cr, Pb, and As were 0.71, 0.81, 0.71, and 0.67, respectively, indicating strong positive spatial autocorrelation and suggesting clustering of similar contamination levels. Conclusively, this research provides a comprehensive framework for predicting heavy metal sediment pollution in the Sundarbans, identifying key areas needing urgent conservation. Our findings support the adoption of integrated management strategies and targeted remedial actions to mitigate the harmful effects of heavy metal contamination in this vital ecosystem.

Enhanced Removal of Pb(II), Paracetamol and Rhodamine B from Aqueous Solutions Using Engineered Low‐Cost Tea Waste‐Based Magnetic Nanocomposite

AbstractThe development of engineered biomass‐based adsorbents capable of efficiently removing pollutants from aqueous solutions has received tremendous attention due to their cost‐effectiveness and renewal potential. Herein, we report a one‐pot synthesis of a low‐cost magnetic composite (Fe3O4‐tea) derived from waste tea and iron oxide magnetic nanoparticles and its application as nanosorbent for the removal of Pb2+, rhodamine B and paracetamol as model pollutants from aqueous solutions. The FTIR, XRD, TGA, BET, TEM and zeta potential studies confirmed the successful synthesis of Fe3O4‐tea with an organic content of 54.55 wt.% and a surface area of 25.32 m2 g−1. The high saturation magnetization (Ms) of the composite estimated to 45.47 emu g−1 allows for its effortless separation and recovery from wastewater solutions using a simple bar magnet. Various theoretical models were considered to study and discuss adsorption isotherms and kinetics. The equilibrium kinetics were found to follow a second‐order model, regardless of the system investigated. Maximum monolayer adsorption capacities of 113.63, 92.59 and 60.24 mg g−1 were obtained for Rhodamine B, Pb2+ and paracetamol, respectively. These values are greater than the adsorption capabilities of several conventional and magnetic sorbents reported in the literature, including activated carbon. The adsorption process mechanism was also discussed based on pH studies. The results suggest that the Fe3O4‐tea adsorbent shows a great potential for effectively removing heavy metal ions and organic pollutants with a rapid uptake rate and easy magnetic separation.

“Crowding Out” or “Reservoir Effect”? Unraveling the Impact of Financialization on Green Innovation in Heavy Polluting Enterprises: Evidence from China’s Listed Companies

In the era of green transformation and sustainable development, green innovation has become a key force driving the greenization of the economy and society, as well as achieving global sustainable development goals. This study aims to investigate the impact of financialization on green innovation in heavy polluting enterprises, a sector where enhancing green innovation capabilities is crucial for both industry transformation and sustained economic growth. As the financialization of enterprises deepens, its effects on green innovation become increasingly significant. Based on data from 667 listed companies in China, we explore the mechanisms through which financialization influences green innovation. Our findings reveal that financialization has both a potential “reservoir” effect, which provides financial support for green innovation, and a significant “crowding out” effect, with the latter outweighing the former, thereby suppressing investment in green innovation. Further analysis indicates that these effects exhibit significant heterogeneity across different property rights, regions, and corporate debt-to-asset ratios. Additionally, the short-term debt-paying ability of enterprises and market competitiveness play important regulatory and threshold roles in this relationship. This study not only provides a new perspective for understanding the relationship between the financialization of heavy polluting enterprises and green innovation but also offers valuable insights for promoting the coordinated development of both and addressing the challenges of green innovation.

Combined effects of organic solvent and ultrasonic pretreatments on cellulose fiber extraction from hemp

Extracting pure cellulose fibers from hemp bast for potential textile industry applications requires the removal of non-cellulosic gummy materials. However, traditional degumming methods are largely limited because of the long procedure time, high energy consumption, heavy environmental pollution and insufficient efficiency. Organic solvents have been proved to be an innovative method for lignocellulose extraction. Herein, ethylene glycol solvent combined ultrasonic pretreatment was explored to degum hemp fibers without any further treatment. The purified hemp fibers were systematically characterized using analytical test techniques. Results revealed that the combined degumming could effectively remove non-cellulosic components without damaging the cellulose, and reducing the reaction temperature by 10 ℃ for reaction process. Comparing to the traditional method, the fibers by ultrasonic pretreatment-ethylene glycol process had superior average yield of 68.32 %, higher thermal stability (maximum degradation temperature reached 395 ℃), higher breaking tenacity of 6.13 cN/dtex, higher crystallinity of 78 % and the cellulose content of over 91 %. Moreover, the degumming time and chemical usage were reduced to 40 % and 51.8 %, respectively. Besides, the changes of fibers chemical structure were further investigated and verified by FTIR, EDS, and 13C NMR analysis. Featured with less chemical and energy consumption, eco-friendly and short time-consuming, this treatment has a broad application scope for hemp cellulose fiber extraction.

Heavy metal's pollution health risk assessment and source appraisal of groundwater and surface water in Irob catchment, Tigray, Northern Ethiopia

Contamination of water resources by heavy metals causes health problems for humans. This study attempts to investigate the heavy metal contamination levels, health risks and sources of appraisal of groundwater and surface water in the mountain-bounded catchment and low-grade basement rock-dominated area of ​​the Irob, Tigray. Eighteen grab water samples (13 borehole water, 2 spring water and 3 surface water) were collected and analyzed for pH, electrical conductivity, total dissolved solids and heavy metals using standard procedures. The findings were contrasted with those of the standards set by the World Health Organization and the United States Environmental Protection Agency. Integrated techniques, including indexed and statistical methods, were used to determine the contamination levels of metals, risks to human health and sources. The result shows that the pH value, electrical conductivity and total dissolved solids fluctuated between 7.4 and 7.9, 516 and 2410 µs/cm and 396.7 mg/l and 1719 mg/l, respectively. The findings indicate that 94.4% of the water samples had levels of contamination above the critical limit for all three indices: the heavy metal evaluation index (HEI), the degree of contamination (cd) and the heavy metal pollution index. The hazard index of metals for adults and children was greater than 1. 88.9% of the water samples showed a cancer risk value above the recommended value (CR > 1 × 10–4) for Cd and Cr for both adults and children. Multivariate statistical analyses indicate that weathering of bedrocks and partly anthropogenic influences are responsible for the metal contamination. The study concludes that some water samples sources are unfit for human consumption that can pose health risks over time. Therefore, it is recommended to treat contaminated water sources to protect and sustain public health.

Simultaneous removal of lead(II) and cadmium(II) from acidic wastewater by Fe-modified sludge biochar

In natural environments, heavy metal water pollution often involves simultaneous presence of various heavy metal ions (HMs), posing significant challenges for their removal. In this study, Fe-modified sludge biochar was synthesized via the co-precipitation method, and the effects of various environmental factors on simultaneously removing lead(II) and cadmium(II) by Fe@SBC were investigated. Batch adsorption experiments showed that Fe@SBC has a higher removal capacities for Pb(II) than for Cd(II) in both single or binary solutions. Increasing solution pH promoted the HMs removal on Fe@SBC. Coexisting divalent cations (Mg2+ and Ca2+) exhibited stronger inhibitory effects on HMs removal by Fe@SBC than monovalent cations (K+ and Na+). The presence of humic acid (HA) did not affect Pb(II) removal on Fe@SBC in either single or binary systems. In single systems, increasing HA concentration enhanced Cd(II) removing on Fe@SBC, while in binary systems, increasing HA concentrations inhibited the Cd(II) removal on Fe@SBC. The sorption of Pb(II) and Cd(II) on Fe@SBC followed the pseudo-second-order kinetic model and the Langmuir model. The removal mechanisms involved electrostatic interactions, complexation with O-containing group, and mineral dissolution-precipitation. After three regenerations, the adsorption capacity of Fe@SBC for Pb(II) and Cd(II) decreased by approximately 5–10 %. In summary, this environmentally friendly composite material has great potential for simultaneously remediating of Pb(II) and Cd(II).

Areas of Heavy Permanent Oil Pollution of the Caspian Sea Surface Identified by Use of Satellite Remote Sensing

Areas of Heavy Permanent Oil Pollution of the Caspian Sea Surface Identified by Use of Satellite Remote Sensing

Characterization, sources, and formation processes of dicarboxylic acids, oxocarboxylic acids and α-dicarbonyls in PM2.5 aerosols in New Delhi

Daytime and nighttime fine aerosol (PM2.5) samples were collected during a heavy pollution episode in November 2020, January 2021, and also during clean event (August 2020) in New Delhi. These samples (n = 20) were analyzed for water-soluble dicarboxylic acids (diacids) and related compounds, carbonaceous components, and inorganic ions to identify their sources and atmospheric processing in different episodes/seasons. Among the measured organics, oxalic acid (C2) was found to be the most abundant species followed by terephthalic (tPh), succinic (C4), phthalic (Ph), and azelaic (C9) acids. Such high abundance of tPh were different from those in other Asian cities where C3 is generally the second or third dominant species. tPh very well correlated with OC, Cl− and K+, indicating combustion of biomass and plastic-containing waste may be the possible sources. Significant high contents of diacids, oxoacids, and dicarbonyls were observed during heavy pollution episode, implying an enhanced emission and/or atmospheric processing of these species. Additionally, two important secondary formation pathways for C2 diacid were discussed in New Delhi, i.e. (i) biomass burning derived (biogenic) volatile organic precursors lead to formation of C2 diacid through transformation of oxoacids and dicarbonyls by oxidation, and (ii) oxidative degradation of the unsaturated fatty acids results in formation of C5 and C4 which subsequently decompose to C2 diacid. This study demonstrated that both primary emissions in clean event and secondary production during polluted event are important sources of aerosols in New Delhi.

The adsorption and fixation of Cd and Pb by the microbial consortium weakened the toxic effect of heavy metal-contaminated soil on rice

With the rapid development of industry and agriculture, the toxicity and pollution of Cd and Pb in soil and plants are becoming increasingly severe. Microbial remediation is considered an economical and sustainable method for addressing heavy metal ion pollution. This experiment established a microbial consortium capable of efficiently adsorbing and fixing Cd and Pb. The consortium consisted of two isolated strains: the straw-degrading bacterium ZJW-6 (Cellulomonas iranensis) and the phosphate-solubilizing bacterium wj1 (Pseudomonas brassicacearum). The microbial consortium exhibited high resistance to Cd and Pb, resulting in a significant reduction in heavy metal toxicity. The minimum inhibitory concentrations of Cd and Pb for the mixed microbial consortium were 900 mg/L and 2500 mg/L, respectively. Results indicated that within seven days, the microbial consortium’s removal rates of Cd and Pb reached 94.25 % and 74 %, respectively, surpassing the removal abilities of the individual member bacteria. It also enriched the soil organic matter and produced larger aggregates to adsorb more heavy metals (Cd: 3.35 mg/kg, Pb: 86.57 mg/kg). By the 60th day, 91.2 % of Cd and 97.89 % of Pb in the soil rhizosphere had been removed, and the free Cd and Pb in plant tissues were significantly reduced. Soil aggregates, which are the basic units of soil and an important index for measuring soil structure, were improved. The microbial consortium also played a significant role in restoring the soil microbial community, mobilizing the combined action of microorganisms represented by Ramlibacter and Sphingomonas to repair heavy metal pollution and promote plant growth. This provides a new method to bioremediate metal-contaminated soil and enhance the plant growth environment.

Ship deployment problem with green technology adoption for an inland river carrier under non-identical streamflow and speed limits

The maritime industry is currently experiencing a shift towards green corridors. The inland waterway is the main transportation corridor with a relatively low adoption of green technologies, which produces heavy air pollution in inland cities. This paper investigates the ship deployment problem for an inland river carrier considering the adoption of green fuel and green technologies for a given ship fleet. A non-linear programming (NLP) model is proposed to jointly optimize green technology adoption, sailing speed, and routing problems while considering two unique characteristics of inland river shipping, including the non-identical streamflow and the speed limits on each shipping leg. The analytical propositions reveal the optimal operation strategy of the inland river ship fleet, and a column generation-based algorithm is further designed to solve the proposed model. By jointly investigating the ship operation strategy and sulphur emissions, we find the following management insights: Firstly, the ship would have a lower willingness to invest in shore power (scrubber) if it installed scrubber (shore power). The higher streamflow and looser speed limits would reduce the spillover effect of green technology adoption. Secondly, emissions will spillover from ports to river legs if only shore power is provided. Our findings provide valuable insights for policymakers to promote complete green technology adoption to achieve comprehensive abatement of the entire inland river.

Triboelectric Nanosensor Fabricated on Robotic Platform for Self-Powered Detection of Heavy Metal Ions in Aquatic Environments

The escalation of heavy metal ions pollution, caused by the natural processes as well as human activities has emerged as a significant global challenge. The accumulation of heavy metal ions in the human body primarily occurs through water and food consumption which poses a severe threat leading to irreversible health damage. To address this issue, the World Health Organization (WHO) has established permissible limits for various heavy metal ions in drinking water, ranging from 0.003 to 3 ppm. When these limits are exceeded, water is deemed contaminated which necessitates effective monitoring and detection strategies. Robotic chemical sensing platforms have become indispensable for tackling chemical threats by detecting harmful pollutants in toxic environments. However, chemical sensors integrated with robotic platforms encounter drawback such as reliance on external power sources. In response to this challenge, our approach integrates a highly sensitive, self-powered triboelectric nanosensor (TENS) into a robotic platform charged by a thermoelectric generator (TEG) and equipped with wireless transmission capabilities. This integration enables the rapid on-site detection of heavy metal ions. The system employs copper electrodes modified with ion-selective membranes (ISM) as sensing probes and solid triboelectric contact materials. Through periodic contact-separation cycles with ionic solutions, the system generates electrical output, facilitating the detection of various concentrations of Pb2+, As3+, and Cr6+ ions. The ionophores in the respective ISMs contribute to the selective binding capacity of the sensing probe to the particular ion. This self-powered robotic platform provides an innovative and cost-effective solution for automated chemical sensing in water environments. Its advantages include the avoidance of external power sources, low-cost operation, and the elimination of the need for frequent battery replacements. With its capability for remote monitoring and detection, this system emerges as an ideal tool for preventing and controlling heavy metal ions pollution, ultimately contributing to the intelligent monitoring of heavy metal ions in aquatic environments. Keywords: Heavy metal ions, Solid-liquid triboelectric nanosensor, Robotic platform, Self-powered detection, Copper electrodes.