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1.
Environ Res ; 245: 118024, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38151151

ABSTRACT

River systems are important recipients of environmental plastic pollution and have become key pathways for the transfer of mismanaged waste from the land to the ocean. Understanding the sources and fate of plastic debris, including plastic litter (>5 mm) and microplastics (MPs) (<5 mm), entering different riverine systems is essential to mitigate the ongoing environmental plastic pollution crisis. We comprehensively investigated the plastic pollution in the catchments of two rivers in the Yangtze River basin: an urban river, the Suzhou section of the Beijing-Hangzhou Grand Canal (SZ); and a pristine rural river, the Jingmen section of the Hanjiang River (JM). The abundance of plastic pollutants in SZ was significantly higher than in JM: 0.430 ± 0.450 items/m3 and 0.003 ± 0.003 items/m3 of plastic litter in the water; 23.47 ± 25.53 n/m3 and 2.78 ± 1.55 n/m3 MPs in the water; and 218.82 ± 77.40 items/kg and 5.30 ± 1.99 items/kg of MPs in the sediment, respectively. Plastic litter and MPs were closely correlated in abundance and polymer composition. Overall, the polymer type, shape and color of MPs were dominant by polypropylene (42.5%), fragment (60.4%) and transparent (40.0%), respectively. Source tracing analysis revealed that packaging, shipping, and wastewater were the primary sources of plastic pollutants. The mantel analysis indicated that socio-economic and geospatial factors play crucial roles in driving the hotspot formation of plastic pollution in river networks. The composition of the MP communities differed significantly between the sediments and the overlying water. The urban riverbed sediments had a more pronounced pollutant 'sink' effect compared with the pristine rivers. These findings suggested that the modification of natural streams during urbanization may influence the transport and fate of plastic pollutants in them. Our results offer pivotal insights into effective preventive measures.


Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Plastics , Rivers , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Microplastics , Water
2.
Adv Mater ; 34(31): e2203792, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35687054

ABSTRACT

Designing scalable coatings with a wide spectrum of functions such as liquid repellency, anticorrosion, and antiflaming and a high level of mechano-chemical-thermal robustness is crucial in real-life applications. However, these individual functionalities and robustness are coupled together or even have conflicting requirements on the interfacial or bulky properties of materials, and thus, simultaneously integrating all these individual features into one coating has proved challenging. Herein, an integral skin-inspired triple-layered coating (STC) that resolves conflicting demands imposed by individual features on the structural, chemical, mechanical, and thermal properties of materials is proposed. Specifically, the rational design of multiple gradients in roughness, wetting, strength, and flame retardancy and the formation of continuous interfaces along its triple layers endow a sustained liquid repellency, anticorrosion, and flame retardancy even under harsh environments, as well as strong antiabrasion on surfaces and adhesion with the substrate. Such an all-in-one design enhances the durability and lifetime of coatings and reduces the maintenance and repair, thereby contributing to cost and energy saving. Together with a facile spraying fabrication process, this STC provides a feasible and sustainable strategy for constructing energy and resource-saving materials.

3.
Ying Yong Sheng Tai Xue Bao ; 33(2): 544-550, 2022 Feb.
Article in Chinese | MEDLINE | ID: mdl-35229529

ABSTRACT

Based on the investigation data of 44 stations in the area 28°ï¼35° N, 147°ï¼154° E of the Northwestern Pacific Ocean by the research ship 'Songhang' in March 2019, we analyzed species composition and distribution of zooplankton to understand zooplankton community structure in the subtropical areas of the Northwestern Pacific Ocean. The results showed that a total of 456 zooplankton species (including planktonic larvae and unidentified species) were recorded in the surveyed area, which were belonged to 8 categories and 14 groups. There were 163 species of copepods, as the dominant group. The dominant species included 9 warm-water species, Eudoxoides spiralis, Neocalanus gracilis, Pleuromamma gracilis, Sagitta enflata, Doliolum nationalis, S. hexaptera, Euchirella rostrata, Nannocalanus minor and Mesocalanus tenuicornis, and one temperate species, Calanus jashnovi. Both the warm current indicator species S. hexaptera and the cold current indicator species C. jashnovi occurred simultaneously in the subtropical area, indicating that the Kuroshio Current and the Oyashio Current had an important impact on the diversity and temporal-spatial distribution of marine zooplankton. The average biomass was (31.64±23.81) mg·m-3, and the average abundance was (22.2±17.6) ind·m-3. The average values of purity index (C), eveness index (J), Shannon diversity index (H) and richness index (D) were 0.09±0.10, 0.76±0.10, 4.88±0.71, and 23.53±8.08, respectively. The spatial distribution of the four indices were uneven and irregular. During the study period, species composition of zooplankton in the Northwest Pacific was rich, species distribution was uneven, and community structure was stable.


Subject(s)
Copepoda , Zooplankton , Animals , Biomass , Pacific Ocean
4.
Nanomaterials (Basel) ; 11(11)2021 Nov 12.
Article in English | MEDLINE | ID: mdl-34835806

ABSTRACT

Fe-doped 0.71Pb(Mg1/3Nb2/3)O3-0.29PbTiO3 (PMN-PT) thin films were grown in Pt/Ti/SiO2/Si substrate by a chemical solution deposition method. Effects of the annealing temperature and doping concentration on the crystallinity, microstructure, ferroelectric and dielectric properties of thin film were investigated. High (111) preferred orientation and density columnar structure were achieved in the 2% Fe-doped PMN-PT thin film annealed at 650 °C. The preferred orientation was transferred to a random orientation as the doping concentration increased. A 2% Fe-doped PMN-PT thin film showed the effectively reduced leakage current density, which was due to the fact that the oxygen vacancies were effectively restricted and a transition of Ti4+ to Ti3+ was prevented. The optimal ferroelectric properties of 2% Fe-doped PMN-PT thin film annealed at 650 °C were identified with slim polarization-applied field loops, high saturation polarization (Ps = 78.8 µC/cm2), remanent polarization (Pr = 23.1 µC/cm2) and low coercive voltage (Ec = 100 kV/cm). Moreover, the 2% Fe-doped PMN-PT thin film annealed at 650 °C showed an excellent dielectric performance with a high dielectric constant (εr ~1300 at 1 kHz).

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