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A quatic plants are an important part of artificial wetlands and lakes and play a crucial role in the nutritional status of aquatic ecosystems. We selected six aquatic plant species for the treatment of water polluted with nitrogen and phosphorus, namely Acorus calamus, Canna indicaˈPistia stratiotes, Eichhornia crassipes, Ceratophyllum demersum, and Myriophyllum spicatum, and combinations thereof, with the aim to establish a dynamic model to determine nutrient absorption rates. The Imax and Iave values of Acorus calamus for TN absorption were the highest. The TN removal rate of Acorus calamus was 83.97–100%, indicating that this species has a greater level of adaptation and absorption potential for TN. Of the single species, Ceratophyllum demersum had the highest TP absorption rate. Of the combinations, Myriophyllum spicatum + Acorus calamus + Eichhornia crassipes had the highest TP removal rate of 98.76%. We used regression analysis to establish the nutrient adsorption function model of aquatic plants. For TN, the model type was a binomial function model y = ax² + bx + c, whereas for TP, it was a trinomial function model y = ax³ + bx² + cx + d. For NH3-N, the most suitable model was an inverse proportional function model y = k/x + b. The six selected aquatic plants can be used in combination with each other for the remediation of eutrophic waterbodies. [ABSTRACT FROM AUTHOR]

Mercury removal from wastewater by plants has attracted widespread research attention because of its negative health effects. This study explored the absorption and enrichment characteristics of aquatic plants under stress from the heavy metal mercury (Hg). The research also investigated the removal effect of aquatic plants on Hg pollution in water, and screened different aquatic plants to determine which were optimal for removing heavy metal polluted water. The six species of aquatic plants included in the study were: Canna indical, Eichhornia crassipes, Pistia stratiotes, Acorus calamus, Ceratophyllum demersum, and Myriophyllum spicatum. Hydroponic experiments were conducted to determine the removal rate of Hg in water and the enrichment characteristics of the aquatic plants under heavy metal Hg stress. The results showed that the six plants had a removal effect on Hg; the removal models were consistent with an exponential curve, meaning that the model effectively predicted mercury concentration in water. The best aquatic plant was Myriophyllum spicatum, with an average removal rate of 94.77 %. At low concentrations, the bioconcentration factors of Myriophyllum spicatum was the highest, which was 923.91. The study concludes that Myriophyllum spicatum is the dominant species for remediating Hg pollution in water, and can be applied to design ecological floating beds. [ABSTRACT FROM AUTHOR]

Impulse pressuring diffusion bonding of commercially pure titanium to 1Cr18Ni9 stainless steel was carried out using a copper interlayer in an attempt to reduce the bonding time and alleviate the detrimental effect of interfacial reaction products on bonding strength. Successful bonding has been achieved at 850 °C under a pulsed pressure of 8∼20 MPa within a duration of only 120∼180 s, which is notably shortened in comparison with conventional diffusion bonding. Microstructure characterization revealed that a sequence of Ti-Cu intermetallic compounds were formed at the Ti/Cu interface and the Cu/stainless steel interface was characterized by the presence of solid solution of Cu in γ Fe without any interfacial reaction products. Maximum bonding strength of 346 MPa was obtained when the joint was bonded for 120 s. Upon tensile loading, the joints fractured along the Ti/Cu interfacial reaction layer in a brittle cleavage manner, indicating that the impulse pressuring diffusion bonding can alleviate the harmful influence of interfacial intermetallic compounds on joint performances to a certain extent, but it is infeasible in completely eliminating the negative effect of the brittle intermetallic compounds. [ABSTRACT FROM AUTHOR]