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Stricter cadmium and lead standards needed for organic fertilizers in China

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science of the Total Environment 2025年 980卷 179561页

作者： Chen, Fengxian Zhou, Bin Zhang, Yexiang Chen, Xijuan Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied Ecology Chinese Academy of Sciences Liaoning Shenyang110016 China Ministry of Education Key Lab for Eco-restoration of Contaminated Environment Shenyang University No. 21 South Wanghua Street Shenyang110044 China Chair of model-based environmental exposure science Faculty of Medicine University of Augsburg Augsburg86159 Germany School of Environmental and Safety Engineering Shenyang University of Chemical Technology Shenyang110142 China

This study aims to evaluate the adequacy of China's national standards for heavy metals in organic fertilizers by predicting their concentrations in grains using machine leaning. A comprehensive dataset was collected from literature, including soil properties, organic fertilizer application rates, and heavy metal concentrations in soils, fertilizers, and grains. Ten key variables were used as inputs for machine learning models developed via H2O AutoML, to predict heavy metal concentrations in maize, wheat, and rice grains across China. The models demonstrated strong predictive performance, with R2 values ranging from 0.74 to 0.95. Predictions were generated using the national standard limits for heavy metals in organic fertilizers, along with geographical feature maps of China and the pre-trained machine learning models, to assess compliance with food safety standards. The results indicated that the current national standards for As, Cr, and Hg in organic fertilizers are adequate, as the heavy metal concentrations in grains remained within safe limits nationwide. However, for Cd and Pb, even when organic fertilizers met the national standard limits, the predicted concentrations in grains exceeded safety standards in 39.1–63.6 % and 81.2–95.5 % of agricultural areas, respectively. These findings suggest that the existing national standards for Cd and Pb in organic fertilizers are too lenient to ensure food safety in China. Stricter regulations are therefore necessary to reduce the risk of heavy metal contamination in staple crops and to safeguard public health. © 2025 Elsevier B.V.

关键词： Fertilizers

A simple approach to measuring upper ocean light quality using an underwater camera

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Intelligent Marine technology and Systems 2025年第1期3卷 1-10页

作者： Yang, Xin Yu, Xiaolong Lin, Gong Wang, Yongchao Lee, Zhongping State Key Laboratory of Marine Environmental Science College of Ocean and Earth Sciences Xiamen University Xiamen China National Observation and Research Station for the Taiwan Strait Marine Ecosystem Xiamen University Zhangzhou China Tianjin Research Institute for Water Transport Engineering National Engineering Research Center of Port Hydraulic Construction Technology Tianjin China

Solar radiation is the fundamental driving force of the Earth’s system. In the upper water column, interactions such as absorption and scattering by water constituents decrease light intensity (photon quantity) and alter light quality (spectral distribution of photons). Although changes in solar intensity have been extensively studied over the years, variations in light quality with depth have received comparatively little scholarly attention. This dearth of research may be due to the lack of simple and cost-effective instruments for measuring light quality, unlike commercial instruments available for measuring solar intensity. In this study, we present a simple approach that uses an underwater camera and a diffuser to measure light quality, represented by the hue angle (HA) of the downwelling irradiance. Our results reveal that the HA from this simple, low-cost device aligns closely with measurements from an expensive hyperspectral radiometer across various water types, ranging from oceanic to coastal waters (R2 = 0.94, mean absolute percentage difference = 1.64%). The widespread adoption of this approach could significantly enhance our understanding of the impact of solar radiation on the biogeochemical processes in aquatic environments.

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Quaternary Ammonium Polymeric Ionic Liquid-Based Effervescence-Enhanced Dispersive Solid-Phase Extraction for Determining Five Sulfonamides Antibiotics in Reclaimed Waters and Their Underlying Interaction Mechanisms

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SSRN 2024年

作者： Gao, Ming Ma, Su Ma, Sai Wang, Xuedong Li, Yanyan School of Environmental Science and Engineering Suzhou University of Science and Technology Suzhou215009 China College of Public Health Wenzhou Medical University Wenzhou325035 China School of Chemistry and Life Science Suzhou University of Science and Technology Suzhou215009 China Key Laboratory of Advanced Electrode Materials for Novel Solar Cells for Petroleum and Chemical Industry of China Suzhou University of Science and Technology Suzhou215009 China

Herein, two kinds of quaternary ammonium polymeric ionic liquids (PILs) were prepared and rigorously characterized based on SEM, FT-IR and 1H NMR data. The PIL-based effervescence-enhanced dispersive solid-phase extraction (PILE-d-SPE) method was developed based on effervescent tablets containing PILs as extractants, tartaric acid as acid source, NaHCO3 as alkaline source, and water-soluble starch as filler. The positive charges on the surface of PILs and the negative charges on the surface of sulfonamide antibiotics (SAs) exhibited significant electrostatic attraction, thereby enhancing interactions between two PILs and SAs. P[VBTHEA]Cl exhibited higher extraction efficiency for five SAs than P[VBTEA]Cl, possibly because the structure of P[VBTHEA]Cl contained more -OH functional groups compared to P[VBTEA]Cl. Before and after extraction, the FT-IR spectra of the two PILs were significantly different from the O-H and C-H stretching-vibration peaks. DFT calculations show that the strong hydrogen bonds formed between P[VBTHEA]Cl and SDM, resulting in the highest binding energy and, consequently, the highest SDM extraction recovery rate. Overall, the H-bonding induction effect was inferred to be the main reason for the superiority of P[VBTHEA]Cl over P[VBTEA]Cl in extraction efficiency. By the one-factor-at-a-time approach, several important variables were optimized for determining SAs in reclaimed waters as follows: 200-mg PILs as extractant, 400-µL acetone as elution solvent, and 5-min elution. By integration with HPLC-DAD detection, this approach provided satisfactory analytical performance: low detection limit (0.19-0.32 μg/L) and appropriately fortified recovery (78.4-89.7%) for five SAs. Consequently, the P[VBTHEA]Cl-based E-d-SPE method presents environmental friendliness, time-saving, easy operation, and excellent analytical performance. © 2024, The Authors. All rights reserved.

关键词： Acetone

In silico bioactivity prediction of proteins interacting with graphene-based nanomaterials guides rational design of biosensor

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arXiv

arXiv 2024年

作者： Ye, Jing Fan, Minzhi Zhang, Xiaoyu Lu, Shasha Chai, Mengyao Zhang, Yunshan Zhao, Xiaoyu Li, Shuang Zhang, Diming Research Center for Intelligent Sensing Systems Zhejiang Laboratory Hangzhou311121 China School of Materials Science and Engineering Suzhou University of Science and Technology Suzhou215009 China College of Materials and Environmental Engineering Hangzhou Dianzi University Hangzhou310018 China Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin300072 China

Graphene-based nanomaterials have attracted significant attention for their potentials in biomedical and biotechnology applications in recent years，owing to the outstanding physical and chemical properties. However, the interaction mechanism and impact on biological activity of macro/micro biomolecules still require more concerns and further research in order to enhance their applicability in biosensors, etc. Herein, an integrated method has been developed to predict the protein bioactivity performance when interacting with nanomaterials for protein-based biosensor. Molecular dynamics simulation and molecular docking technique were consolidated to investigate several nanomaterials: C60 fullerene, single-walled carbon nanotube, pristine graphene and graphene oxide, and their effect when interacting with protein. The adsorption behavior, secondary structure changes and protein bioactivity changes were simulated, and the results of protein activity simulation were verified in combination with atomic force spectrum, circular dichroism spectrum fluorescence and electrochemical experiments. The best quantification alignment between bioactivity obtained by simulation and experiment measurements was further explored. The two proteins, RNase A and Exonuclease III, were regarded as analysis model for the proof of concept, and the prediction accuracy of protein bioactivty could reach up to 0.98. The study shows an easy-to-operate and systematic approach to predict the effects of graphene-based nanomaterials on protein bioactivity, which holds guiding significance for the design of protein-related biosensors. In addition, the proposed prediction model is not limited to carbon-based nanomaterials and can be extended to other types of nanomaterials. This facilitates the rapid, simple, and low-cost selection of efficient and biosafe nanomaterials candidates for protein-related applications in biosensing and biomedical systems. Copyright © 2024, The Authors. All rights reserved.

关键词： Proteins

PFC numerical simulation study of thermal-mechanical coupling of sandstone under unidirectional heating 3

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PFC numerical simulation study of thermal-mechanical couplin...

2021 3rd International Conference on Polymer Synthesis and Application, ICPSA 2021

作者： Xin, Lin An, Mingyu Feng, Mingze Cheng, Weimin Li, Kaixuan Wu, Jing Li, Jiaze College of Safety and Environmental Engineering Shandong University of Science and Technology Shandong Qingdao266590 China Key Laboratory of Ministry of Education for Mine Disaster Prevention and Control Shandong University of Science and Technology Shandong Qingdao266590 China

In order to study the rock thermal cracking law of the roof rock in the combustion zone of underground coal gasification under the special condition of unidirectional heating, the PFC particle flow software was used to carry out the numerical simulation of thermal-mechanical coupling. The uniaxial compression experiment was used to complete the PFC parameter calibration, establish a mechanical model, and compare the results of the unidirectional heating test with the simulation results. It was found that the relationship between the temperature at the measuring point, the thermal stress and the heating time of the two is very similar. It shows that the simulation results are highly accurate. The simulation results are as follows: when the model is at 450°C and 600°C, larger-scale cracks are formed and the second larger-scale crack evolution occurs;acoustic emission simulation can be divided into three stages: the first peak stage, the energy accumulation stage, and the second stage. In the second peak stage;the number of model cracks increases with the increase in temperature, and the shear cracks are the main ones, indicating that the model will expand laterally after being subjected to thermal stress, mainly occurring shear failure. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Heating

Polaron-assisted nonadiabatic dynamics in protonated TiO_(2) with surface water molecule

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ChemPhysMater 2023年第4期2卷 331-336页

作者： Zhongfei Xu Chuanjia Tong Rutong Si Gilberto Teobaldi Limin Liu The Key Laboratory of Resources and Environmental System Optimization Ministry of EducationCollege of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China School of Physics and Electronics Central South UniversityChangsha 410083China Beijing Computational Science Research Center Beijing 100193China The Abdus Salam International Centre for Theoretical Physics Trieste 34151Italy Scientific Computing Department Science and Technology Facilities Council UK Research and Innovation(STFC-UKRI)Rutherford Appleton LaboratoryHarwell CampusDidcot OX110QXUnited Kingdom School of Chemistry University of SouthamptonHighfieldSouthampton SO171BJUnited Kingdom School of Physics Beihang UniversityBeijing 100191China

We investigated the polaron-assisted nonadiabatic dynamics in protonated TiO_(2),as well as the polaron-H_(2)O coupling and its effects on the relaxation of photogenerated *** observed that different polaron hopping regimes result in varied nonadiabatic couplings and relaxations of excited electrons from the conduction band minimum to the gap states of protonated TiO_(2),with a weak dependence on the actual trapping site of the ***-adsorbed H_(2)O molecules can attract polarons toward the adsorbed Ti sites,with the coupling between H_(2)O and the polaron being inversely proportional to their *** findings suggest that the lifetime of the photogenerated charge carriers can be extended by reducing the polaron-H_(2)O distances,with expected benefits to the efficiency of the reduced TiO 2 samples for photocatalytic applications.

关键词： Protonated Polaron-H_(2)O coupling Nonadiabatic molecule dynamics Lifetime Anatase

Simultaneous Removal of Cyanobacteria and Algal Organic Matter (Aom) with CacO3 Precipitation Strategy

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SSRN 2024年

作者： Nie, Xiaobao Li, Yinan Ouyang, Shuai Wang, Zhengbo Wang, Guoqi School of Hydraulic & Environmental Engineering Changsha University of Science and Technology No. 960 Section 2 Wanjiali South Road Tianxin District Changsha410114 China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha410114 China

Simultaneous removal of cyanobacteria and algal organic matter (AOM) is still a difficult task for drinking water treatment plants (DWTPs) during cyanobacteria blooms. CaCO3 precipitation, an environment-friendly drinking water treatment technique, has been recommended to removal cyanobacteria or AOM from drinking water. However, literature concerning simultaneous removal performance is rare. Here, the simultaneous removal performance to cells and AOM of CaCO3 precipitation, combined with polyaluminum chloride (PACl) coagulation, was investigated, as well as the underlying mechanisms. The results showed that CaCO3 precipitation strategy significantly improved the simultaneous removal performance of PACl, with removal efficiency up to 98% for cells and 48% for AOM. CaCO3 precipitation exhibited reliable simultaneous removal effects at various initial cells densities and initial AOM concentrations. Scanning electron microscope (SEM), transmission electron microscope (TEM) and zeta potential results suggested that mutual flocculation between positively charged CaCO3 crystalline particles and negatively charged cells is the main responsible mechanism for cells removal. Despite that the adsorption of AOM on CaCO3 nuclei surface delays its precipitation, co-precipitation removal mechanism of AOM is realized during CaCO3 nucleation. Moreover, further AOM removal can be obtained by CaCO3 crystalline particles via chemisorption between organic molecules and the particles surface. © 2024, The Authors. All rights reserved.

关键词： Flocculation

In-Situ Heterogeneous Electro-Fenton Based on B, Fe-Modified Carbon Felts for Phosphorus Nutrients Treatment in Dredged Sediment

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SSRN 2023年

作者： Xia, Jing Cai, Jingju Wang, Ping Cao, Jingxiao Zhu, Jian Huang, Chengfeng Liu, Jiahao Liu, Junwu Fang, Yingchun College of Environmental Science and Engineering Central South University of Forestry and Technology Changsha410007 China Hunan Key Laboratory of Wetland and Soil Ecological Restoration College of Environmental Science and Engineering Central South University of Forestry and Technology Changsha410004 China College of Chemistry and Bioengineering Hechi University Guangxi Yizhou546300 China Hunan Kaidi Engineering Technology Co. Ltd. Changsha410004 China

A novelty in-situ heterogeneous electro-Fenton based on boron-modified and co-modified cathodes (B-CF, B, Fe-CF and B, Co-CF) was employed for phosphorus nutrients treatment in dredged sediment. During which B, Fe-CF (1:1) was the optimal cathode for phosphorus nutrients and organic matter treatment with organic phosphorus (OP), iron phosphate salt (Fe-P) conversion rates of 26.84% and 63.21%, respectively, due to the fact that the generated H2O2 on bifunctional cathode could produce ·OH with material surface reduced Fe(II). Characterized by SEM, XRD and XPS, B and Fe were successfully loaded on the electrode with elemental percentages of 0.99% and 4.40%, while B2O3 and Fe2O3 were detected. The operating parameters like initial pH and current density were explored. B, Fe-CF had a high stability and outstanding catalytic capacity for 5 cycles phosphorus nutrients treatment. The possible mechanism was also proposed based on the electron paramagnetic resonance (EPR) and radical quenching experiment, which demonstrated that ‧OH and SO4·- mainly contributed to phosphorus nutrients treatment. In this work, a highly efficient and stable carbon material was successfully prepared to treat refractory pollutants in dredging sediment, which provides new ideas and methods for subsequent resource utilization. © 2023, The Authors. All rights reserved.

关键词： Chemical modification

Enhanced Aerobic Granular Sludge (Ags) By Thermally-Treated Dredged Sediment In Wastewater Treatment Under Low Superficial Gas Velocity (Sgv)

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SSRN 2024年

作者： Lin, Qingxia Sun, Shiquan Yang, Jianbin Hu, Pei Liu, Zhengrong Liu, Ziqiang Song, Chuxuan Wu, Fangtong Gao, Yang Zhang, Wei Zhou, Lean Li, Yifu Yang, Suiqin Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province School of Hydraulic and Environmental Engineering Changsha University of Science and Technology Changsha410114 China Hunan Hengyong Expressway Construction and Development Co. Ltd. Hunan 421600 China

The resource utilization of dredged sediment has received extensive attention. To promote AGS formation and stability, the dredged sediment was thermally-treated to prepared as a carrier. The system was started under low SGV (0.6 cm/s) for a lower energy consumption. Two SBR reactors labeled R1 (no added carriers) and R2 (carriers added), were used in the experiment. R2 had excellent performance of granulation time (shortened nearly 43%). The maximum mean particle size at the maturity stage of AGS in R2 (0.545 mm) was larger compared to R1 (0.296 mm). It was found that the carriers stimulated the secretion of extracellular polymeric substances (EPS), which promoted AGS formation. The sludge settling performance in R2 was better. The reactors exhibited high chemical oxygen demand and ammonia nitrogen removal rates. The TP removal rate in R2 was higher than R1 (almost 15% higher) on stage II (93-175d). R2 had a higher microbial abundance and dominant bacteria content. The relative abundance of dominant species was mainly affected by the carrier. However, the enrichment of dominant microorganisms and the evolution of subdominant species were more influenced by the increase of SGV. This work provided a low-cost method and condition to enhance aerobic granulation. © 2024, The Authors. All rights reserved.

关键词： Chemical oxygen demand