ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2025
·
IF 11.3
Yi Liang,Jingyi Gu,Ketong Chen,Hong Zhou,Jiamin Peng,Tingting Cai,Pei Na,Chenlu Guo,Weilin Huang,Chen Yang,Zhi Dang
Settling plays a crucial role in determining the residence time, distribution, transport, and ultimate fate of microplastics (MPs) in aquatic environments. The settling dynamics of particles are influenced by their macroscale shape, mesoscale roundness, and microscale surface properties, along with ambient fluid flow conditions. Variations in the wettability of submillimeter MPs affect molecular interactions at the particle–water interface, altering the microscopic flow field and subsequently modifying drag forces during settling. This study examines the impact of wettability on the settling behavior of aged acrylonitrile butadiene styrene MPs by measuring their settling velocities and contact angles. It was shown that increased wettability promotes the settlement of the MPs. A drag model incorporating the Eötvös number─a dimensionless ratio of buoyancy energy to contact angle-derived surface energy─is developed to quantify the relationship between interfacial chemistry and hydrodynamic resistance. Unlike the conventional models, our model considers wettability as a key factor controlling the settling of MP particles. The model was validated using independently measured data and four sets of published data for the MPs. Results demonstrate that the model significantly improves the accuracy of the settling predictions for weathering spherical MPs. Additionally, by integrating the shape factor, it effectively accounts for the settling behavior of irregularly shaped MPs using published data sets. This improvement enhances predictability for MP transport pathways, helping assess MP accumulation zones and potential ecological risks in marine and freshwater systems.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Jing Wang,Pengxiang Zhu,Meiyu Li,Rui Lu,Xinping Yu,Lezun Wang,Lining Zhao
This study investigated how natural organic matter (NOM) affected the aggregation, dissolution and sedimentation of cadmium telluride quantum dots (CdTe QDs) in artificial freshwater and seawater, with a focus on the impact of NOM species and the mechanism of CdTe QDs-NOM interactions. Results found that NOM dispersed CdTe QDs aggregates by providing electrosteric stabilization and promoted the dissolution by facilitating their contact in most cases. Among the tested NOM, fulvic acid (FA) was the most effective for releasing Cd 2+ in freshwater due to the strongest binding affinity complexing with CdTe QDs. The sedimentation rate of CdTe QDs was accelerated by humic acid (HA) or FA but was slowed by bovine serum albumin (BSA). Isothermal titration calorimetric experiments suggested that CdTe QDs interact with three species of NOM primarily through hydrophobic forces. Approximately five units of HA and three units of BSA bind to one unit of CdTe QDs with the binding affinity of 5.24 × 10 4 M −1 and 2.40 × 10 3 M −1 , respectively. While about eight units of CdTe QDs and one unit of CdTe QDs bind to one unit of FA for the two binding sites with the binding affinity of 1.62 × 10 6 M −1 and 2.16 × 10 3 M −1 . Fourier transform infrared, UV–vis adsorption and three-dimensional fluorescence spectroscopy indicated that QDs-HA interactions affecting HA structure were mainly assigned to the aromatic skeleton of HA and were dominated by the nano-form of CdTe QDs rather than Cd 2+ . This study is helpful for better understanding the fate and transport of CdTe QDs in aquatic environment.
研究领域:
环境科学
·
纳米生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 4.446
Lei Wang,Qi-meng Lu,Tao Zeng,Jing-wen Yang,Xue-qin Hu,Hong-bin Zhang
As a promising material in the field of wastewater treatment , polysaccharide-modified flocculants have received increasing attention due to their environmental friendliness. In this study, an efficient and environmentally friendly flocculant was synthesized using a graft copolymerization reaction of dextran and [2-(methacryloyloxy) ethyl] trimethylammonium chloride (METAC). The reaction conditions were optimized at 3 mol/mol METAC/dextran, 60 g/L dextran concentration, 3 h reaction time, 60 ℃ and pH 7. The results of elemental analysis, Fourier transform infrared (FTIR) spectroscopy, NMR hydrogen spectroscopy ( 1 H NMR), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA) and viscosity measurement confirmed that the graft copolymerization reaction was successful. When flocculating a kaolin suspension used as synthetic wastewater, the flocculant showed effective flocculation performance at a low dosage. The results indicate that this cationic polysaccharide flocculant removed 98.2% of the kaolin solid suspended particles. Investigation of the flocculation mechanism showed that the flocculation process consisted of charge neutralization, charge patching and adsorption bridging mechanisms. When flocculating an E. coli culture medium, this flocculant showed high efficiency under acidic, neutral and alkaline conditions. In addition, this flocculant can be easily biodegraded by the enzymatic method . As a biomaterial, this cationic dextran derivative can contribute to future treatment of industrial wastewater and harvesting of microbial cells.
研究领域:
环境科学
·
材料科学
·
废水处理
✓ 已验证
DOI
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2020
·
IF 4.039
Yunchao Wu,Xiaoping Huang,Zhijian Jiang,Songlin Liu
The phosphorus in precipitation provides a significant fraction of the bioavailable phosphorus to fresh and marine waters. To identify the possible sources and interpret the atmospheric deposition processes of phosphorus, we measured the phosphate oxygen isotopes (δ 18 O P ) in the precipitation monthly from October 2015 to March 2017 in Daya Bay, South China Sea. The isotopic results show that the δ 18 O P values in the dry season (+19.60‰ to +25.80‰, +23.10‰ average) were significantly higher than those in the wet season (+12.52‰ to +20.11‰, +16.73‰ average), indicating a variable contribution from different phosphorus sources to the precipitation between seasons. The δ 18 O P value was primarily influenced by the phosphorus concentrations, rainfall, and air temperature. The exchange of phosphate molecules among phosphorus pools caused isotope dilution (wet season) or enrichment effects (dry season) during the seasonal shifts. The δ 18 O P value of the precipitation and the local end-members indicate that coal combustion (39% ± 16%), biomass burning (22% ± 18%), and soil (17% ± 13%) sources dominate in the dry season, whereas marine sources (28% ± 19%) and coal combustion (24% ± 12%) account for the highest proportion in the wet season using a MixSIAR model. The atmospheric wet deposition flux of phosphorus in Daya Bay was 379.0 μmol m −2 ·yr −1 . The wet deposition of phosphorus exhibits a significant seasonal trend with higher deposition fluxes in the wet season than in the dry season as a result of higher rainfall and source shifts (local sources to marine source) between seasons.
研究领域:
环境科学
·
海洋学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Xi Mu,Zhanxiang Wang,Lichun Liu,Xiaohong Guo,Chen Gu,Hua Xu,Liuyuan Zhao,Wanyanhan Jiang,Hongmei Cao,Xiaoxuan Mao,Tao Huang,Hong Gao,Jianmin Ma
In this study, we collected 308 serum samples from 17 to 20 year old first-year university students who were recruited from Lanzhou University in China a few days after their enrollment to measure the serum Pb, Cd, Hg, and As levels, and specific questionnaires for age, sex, settlement and dietary structure were designed. A 3-D atmospheric transport model was used to simulate the atmospheric concentration and dry deposition across China based on gridded Pb emission inventory to examine the association between the spatial distribution of serum concentrations and environmental fates of Pb. The mean serum Pb, Cd, Hg, and As concentrations averaged over all participating young students were 21.38, 1.46, 3.86, and 4.69 μg/L, respectively. The Pb, Cd, and Hg levels in 3%, 7%, and 20% serum samples exceeded the standards. The minimum serum As and Hg concentrations and the maximum serum Pb and Cd concentrations occurred in urban areas. Seafood diet habits ( P < 0.05), sex ( P < 0.05), and relocation ( P < 0.01) caused significant differences in serum As, Pb, and Cd concentrations. A cluster analysis was carried out to classify the exposure pathways for target contaminants. The results indicated that 4 heavy metals in the serum of volunteers from northern China could be grouped into the same category, in which significant positive correlations were found between the serum heavy metal levels and background concentrations of surface soil. However, in other provinces and metropolises, the atmospheric pollution level played a critical role involving in the inhalation exposure pathway. We demonstrated that serum Pb levels in freshman students were related to the atmospheric transport and dry deposition of Pb.
研究领域:
环境科学
·
公共卫生
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY
·
2020
·
IF 1.22
Shu Wang,Mei Wei,Bingde Wu,Huiyuan Cheng,Kun Jiang,Congyan Wang
Large amounts of nitrogen (N) enter ecosystems via N deposition. The increased drought stress has incurred serious threats to plant seed germination and seedling growth (SGe-SGr). It is significant to characterize the combined impacts of N deposition and drought stress on SGe-SGr of plants to enable a further explanation of the response mechanism of SGe-SGr to N deposition and drought stress. This study aims to explore the combined impacts of N deposition with a concentration gradient and drought stress (mimicked using PEG 6000) with different levels on SGe-SGr of wheat. N treatment raises seedling growth of wheat mainly due to the increased levels of available N and the decreased level of peroxidation of the cell cytoplasm membrane of wheat. Drought stress declines SGe-SGr of wheat mostly due to the progressively enlarged osmotic pressure triggered by water deficit and the advanced level of peroxidation of the cell cytoplasm membrane of wheat. N treatment regardless of the concentration dramatically mitigates the adverse impacts of drought stress on seedling growth of wheat. This may be owed to the improved competitive ability for sunlight acquisition and leaf photosynthetic area via the deactivation of nutrition limits (wheat can absorb more N nutrients and improve its drought resistance ability) implemented by N addition. This may also due to the down-regulated level of peroxidation of the cell cytoplasm membrane of wheat under the combined N and drought stress. However, the combined treatments of the high level of N supply and light drought stress decline seed germination of wheat. This may be due to the promoted osmotic pressure contributed by the high level of N supply under water deficit. Thus, N deposition mitigates the adverse impacts of drought stress on seedling growth of wheat but aggravates the adverse impacts of drought stress on seed germination of wheat mostly.
研究领域:
植物学
·
生态学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Research and Technology-JMR&T
·
2021
·
IF 5.039
Haipei Zhang,Bo Li,Yonggang Wei,Hua Wang
Settling time, system temperature and reductant amount play an important role in the recovery of matte from copper slag. This study investigated the settling behavior of matte particles in copper slag and the effects of the settling time, system temperature, and reductant amount on the macrostructure of slag, microstructure of matte particles, and copper loss. The results showed that the settling behavior of matte particles in slag at the experimental temperature was a process of aggregation and growth. With an increase in settling time and temperature, as well as the addition of an appropriate amount of anthracite, the foaming slag layer of the slowly cooled slag gradually disappeared, while the recovery of matte increased. However, when the amount of anthracite was too high, Fe–Cu alloy formed at the experimental temperature, which resulted in worsened fluidity of the matte in the molten slag and copper loss increased. At the experimental temperature, the settling environment of matte particles in the liquid phase layer was superior to that of the foaming slag layer. The novel idea of using rubber seed oil instead of a traditional fossil reductant to clean the copper slag was put forward. At the temperature of 1250 °C, 4 mL of rubber seed oil was injected, resulting in a settling time of ≥90 min, after which the copper content in the upper part of the slowly cooled slag was less than 0.57 wt.%, reaching the acceptable level of discardable slag in industry.
研究领域:
冶金学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 21
·3844
·
IF 5.719
Zhenlan Xu,Qing Tang,Aimei Hong,Lingxiangyu Li
Along with the development of nanotechnology, nanomaterials have been gradually applied to agriculture in recent years, such as Cu(OH)2-nanorods-based nanopesticide, an antibacterial agrochemical with a high efficacy. Nevertheless, knowledge about physical stability of Cu(OH)2nanopesticide in soil solutions is currently scarce, restricting comprehensive understanding of the fate and risk of Cu(OH)2nanopesticide in the soil environment. Herein we investigated aggregation, sedimentation and dissolution of Cu(OH)2nanopesticide in soil solutions extracted from three different soil samples, wherein commercial Cu(OH)2nanopesticide formulation (NPF), as well as its active ingredient (AI) and laboratory-prepared Cu(OH)2nanorods (NR) with similar morphology as AI, were used as model Cu(OH)2nanopesticides. We found that NPF compared to AI showed less extents of aggregation in ultrapure water due to the presence of dispersing agent in NPF. Yet, moderated aggregation and sedimentation were observed for Cu(OH)2nanopesticide irrespective of NPF, AI or NR when soil solutions were used instead of ultrapure water. The sedimentation rate constants of AI and NPF were 0.023 min−1and 0.010 min−1in the ultrapure water, whereas the rate constants of 0.003–0.021 min−1and 0.002–0.007 min−1were observed for AI and NPF in soil solutions, respectively. Besides aggregation and sedimentation, dissolution of Cu(OH)2nanopesticide in soil solutions was highly dependent on soil type, wherein pH and organic matter played important roles in dissolution. Although the final concentrations of dissolved copper (1.08–1.37 mg/L) were comparable among different soil solutions incubating 48 mg/L of AI, NPF or NR for 96 h, a gradual increase followed by an equilibrium was only observed in the soil solution from acidic soil (pH 5.16) with the low content of organic matter (1.20 g/kg). This work would shed light on the fate of Cu(OH)2nanopesticide in the soil environment, which is necessary for risk assessment of the nanomaterials-based agrochemical.Keywords:soil solutions;aggregation;sedimentation;Cu(OH)2nanopesticide;dissolution
研究领域:
环境科学
·
农业科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2023
·Vol. 332
·期 4
·999-1005
·
IF 1.6
Luo Maoyi,Liu Daqian,Dai Xiongxin,Wu Yang,Yuan Ni
A simple and sensitive method was developed for 239, 240 Pu determination of sub-femtogram level in grass/vegetable sample using compact accelerator mass spectrometry (AMS). Pu was leached with HNO 3 -H 2 O 2 after ashing, and purified with AGMP-1 M resin column from grass matrix. After target preparation using mixed titanium/iron oxides, the final sample was measured by 300 kV AMS. The average recovery was higher than 80% for large-size (> 20 g ) grass sample in the entire procedure. 20 g environmental grass samples spiked with known amounts of 239 Pu standard solution or certified reference materials were measured for method evalution, good agreement between the expected values and measured results has been achieved. The detection limits were estimated to be 1.5 × 10 –16 g (0.34 µBq) for 239 Pu and 9 × 10 –17 g (0.8 µBq) for 240 Pu, demonstrating the feasibility of AMS for the determination of the sub-femtogram level of 239,240 Pu in environmental grass with global fallout signatures. Grass samples collected from China natural environment were successfully analyzed, and 239+240 Pu concentration down to 1.6 × 10 − 4 Bq/kg were measured in these samples. This improvement can stimulate environmental monitoring, ecological migration process and biological availability studies of Pu in the biosphere.
研究领域:
环境科学
·
核化学
·
分析化学
✓ 已验证
DOI
高影响因子
PHYSICS OF FLUIDS
·
2024
·Vol. 36
·期 6
·
IF 4.1
Hu Jun,Zhao Haonan,Xu Zhen,Hong He,Wang Zhan-Long
Anti-condensation is important in various fields, e.g., transportation, power transmission, internal drying of precision instruments. Vapor sink is an important manner to suppress the happening of water vapor condensation, and shows potentials in some special scenarios. However, the mechanism of anti-condensation by vapor sink is not well understood up until now. In this article, the effect of substrate temperature on the dry zone generated by vapor sink were systematically studied with experiments and theoretical analysis. First, the effect of hygroscopic solutions on the local humidity were measured. The results indicated that the local humidity level near the hygroscopic solutions was effectively suppressed, reducing the water vapor condensation. Second, the variation of the dry zone with the cooling substrate temperature was systematically studied. The results indicated that the dry zone exhibits a hyperbolic relationship with the substrate temperature. The dry zone changing under different humidity conditions and cooling time were also studied. The dry zone remained approximately unchanged over time in a short period. Finally, a simple yet effective model between the dry zone and substrate temperature was deduced. The theoretical results are in good agreement with the experimental data. Our study may deeper the understanding of condensation suppression via vapor sink and offer guidance to the design of anti-condensation or anti-icing surfaces.
研究领域:
工程热物理
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Atmosphere
·
2024
·Vol. 15
·期 7
·825
·
IF 2.5
Chuang Li,Yue Li,Yingsheng Liu,Shanshan Zhong,Huanshi Zhang,Zhelun Xu,Zhongyi Xu,Daolin Du,Congyan Wang
One of the key reasons for the success of invasive plants is the functional differences between invasive plants and native plants. However, atmospheric nitrogen deposition may disrupt the level of available nitrogen in soil and the functional differences between invasive plants and native plants, which may alter the colonization of invasive plants. Thus, there is a pressing necessity to examine the effects of atmospheric nitrogen deposition containing different nitrogen components on the functional differences between invasive plants and native plants. However, the progress made thus far in this field is not sufficiently detailed. This study aimed to elucidate the effects of artificially simulated nitrogen deposition containing different nitrogen components (i.e., nitrate, ammonium, urea, and mixed nitrogen) on the functional differences between the Asteraceae invasive plantBidens pilosaL. and the Asteraceae native plantPterocypsela laciniata(Houtt.) Shih. The study was conducted over a four-month period using a pot-competitive co-culture experiment. The growth performance ofP. laciniata, in particular with regard to the sunlight capture capacity (55.12% lower), plant supporting capacity (45.92% lower), leaf photosynthetic area (51.24% lower), and plant growth competitiveness (79.92% lower), may be significantly inhibited under co-cultivation condition in comparison to monoculture condition.Bidens pilosaexhibited a more pronounced competitive advantage overP. laciniata, particularly in terms of the sunlight capture capacity (129.43% higher), leaf photosynthetic capacity (40.06% higher), and enzymatic defense capacity under stress to oxidative stress (956.44% higher). The application of artificially simulated nitrogen deposition was found to facilitate the growth performance of monoculturalP. laciniata, particularly in terms of the sunlight capture capacity and leaf photosynthetic area.Bidens pilosaexhibited a more pronounced competitive advantage (the average value of the relative dominance index ofB. pilosais ≈ 0.8995) thanP. laciniataunder artificially simulated nitrogen deposition containing different nitrogen components, especially when treated with ammonium (the relative dominance index ofB. pilosais ≈ 0.9363) and mixed nitrogen (the relative dominance index ofB. pilosais ≈ 0.9328). Consequently, atmospheric nitrogen deposition, especially the increased relative proportion of ammonium in atmospheric nitrogen deposition, may facilitate the colonization ofB. pilosavia a stronger competitive advantage.
研究领域:
生态学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
Science of Nature
·
2017
·Vol. 104
·期 7
·1-9
·
IF 1.191
Wang Congyan,Zhou Jiawei,Liu Jun,Jiang Kun
Differences in functional traits between invasive and native plant species are believed to determine the invasion success of the former. Increasing amounts of anthropogenic nitrogen (N) are continually deposited into natural ecosystems, which may change the relative occurrence of the different N deposition forms (such as NH 4 –N, NO 3 –N, and CO(NH 2 ) 2 –N) naturally deposited. Under high N deposition scenarios, some invasive species may grow faster, gaining advantage over native species. In a greenhouse experiment, we grew invasive and native Amaranthus species from seed both alone and in competition under simulated N enriched environments with different forms of N over 3 months. Then, we measured different leaf traits (i.e., plant height, leaf length, leaf width, leaf shape index, specific leaf area (SLA), and leaf chlorophyll and N concentrations). Results showed that the competition intensity between A. retroflexus and A. tricolor decreased under N deposition. This may be due to the large functional divergence between A. retroflexus and A. tricolor under simulated N deposition. Phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus were significantly lower than in A. tricolor . The lower range of phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus may indicate a fitness cost for plastic functional traits under adverse environments. The restricted phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus may also stabilize leaf construction costs and the growth rate. Meanwhile, the two Amaranthus species possessed greater plasticity in leaf N concentration under NO 3 –N fertilization, which enhanced their competitiveness.
研究领域:
生态学
·
植物生理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）