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In order to investigate the function of submerged aquatic plants for recovery of water polluted by typical organic pollutants, and select potential plants for phytoremediation of polycyclic aromatic hydrocarbons contaminated water, removal efficiencies of four submerged macrophytes to phenanthrene were investigated, following 40-day exposure to phenanthrene solutions in an outdoor-simulated experiment. During the exposure period, phenanthrene concentration in water, sediments and the roots of submerged macrophytes were observed. Results showed that Elodeacanadensi exhibited the highest concentrations in roots, while Ceratophyllum demersum contained the lowest among these four submerged macrophytes. The disparity of phenanthrene in roots would come from plant properties including the shape and surface area of both shoots and roots. These plants enhanced the remediation of phenanthrene in solution through plant-promoted sedimentation and biodegradation. Potamogetoncrispu and Elodeacanadensi showed the higher performance to remove phenanthrene due to plant-promoted biodegradation.

La3+ adsorption isotherms to five soil constituents (quartz, feldspar, kaolinite, goethite and humic acid) are studied. EDTA, fulvic acid and pH effects are also investigated on the adsorption of lanthanum by goethite and humic acid because of their relative importance in affecting metal environmental behavior. Adsorption isotherms of La3+ to five constituents show differences in adsorption capacity and in shape in the studied range of La3+. These constituents can be classified according to their adsorption capacity: humic acid > goethite ≈ kaolinite > feldspar ≈ quartz. pH increase could promote humic acid and goethite adsorption of La3+ while EDTA could reduce the adsorption by these two adsorbents. Fulvic acid can reduce humic acid adsorption but has less effect on adsorption by goethite.

Water flea ( Daphnia magna ) and fish ( Carassius auratus ) at trophic level were used for comprehensive evaluation of environmental risks incurred by manufactured nanomaterial ( n Ni(OH) 2 ) as leaked from lithium cells to the food chain in freshwater ecosystem. The 48, 72 and 96 h acute toxicities of water suspensions of n Ni(OH) 2 to the flea and the fish were tested, using the immobilization and the mortality as toxicological endpoints. The results showed that the water flea was more highly sensitive to n Ni(OH) 2 than the fish. Then, the fish were exposed to 1.0 mg/L n Ni(OH) 2 for 6, 12, 24, 36, 48, 60, 72 and 96 h, and the relationship between the concentrations in the water and the fish were described by a bioconcentration factor (BCF). After calculation, lgBCF is 1.61. Reactive oxygen species (ROS) generation was studied after fish were exposed to 1.0 mg/L water suspensions of n Ni(OH) 2 for 24 h. As proved by electron paramagnetic resonance, n Ni(OH) 2 may induce the generation of hydroxyl radical in the fish, and n Ni(OH) 2 as concentrated in the fish may incur redox reaction and produce redox metabolic intermediates. As one of the important toxic mechanisms of n Ni(OH) 2 to the fish, the oxidative stress mechanism requires further study.

Bulk tungsten and tungsten transmission electron microscopy (TEM) lamella are implanted with 15 keV helium ions at about 873 K to study the microstructure evolution. The samples are implanted to about 11017 He+/cm2. The projected range of the helium ion in tungsten is about 43.9 nm, calculated with the stopping and range of ions in matter program (the SRIM code). The density of pores with diameters ranging from 90 nm to 430 nm is detected on the surface of helium implanted bulk tungsten by field emission scanning electron microscopy. Blistering is also observed on the surface of helium implanted bulk tungsten. The TEM results indicate that fuzz microstructure is formed in helium implanted tungsten TEM lamella, and stacking faults and micro-pores are observed in the fuzz structure. Besides, the density of nano-scaled helium bubbles is detected around the mirco-pores.

Effects of helium implantation on silicon carbide (SiC) and graphite were studied to reveal the possibility of SiC replacing graphite as plasma facing materials. Pressureless sintered SiC and graphite SMF-800 were implanted with He+ ions of 20 keV and 100 keV at different temperatures and different fluences. The He+ irradiation induced microstructure changes were studied by field-emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM).

Physiological and biochemical perturbations in the liver of Carassius auratus were investigated in vivo following 40 days of exposure to ytterbium solutions of different concentration. Glutamate–pyruvate transaminase (GPT) activity in goldfish liver was stimulated at 0.05 mg/L Yb 3+ and inhibited at higher Yb 3+ concentrations. Activity of the antioxidant enzyme superoxide dismutase (SOD) was stimulated at Yb 3+ higher than 0.05 mg/L, and catalase (CAT) activity was strongly inhibited after 40 days of exposure. Detoxifying enzymes glutathione S -transferase (GST) and glutathione peroxidase (GSH-Px) were stimulated at 0.05 mg/L and inhibited at 0.1 mg/L after 40 days of exposure. Among the parameters determined, CAT in goldfish liver was most sensitive to Yb 3+ , indicating that CAT might be considered a potential tool in the biomonitoring of exposure to Yb 3+ in an aquatic ecosystem.