Graphene-supported bimetal phosphorus trisulfides as novel 0D–2D nanohybrid for high rate Li-ion storage

Herein, we report on the synthesis and Li-ion storage properties of the 0D–2D nanohybrid consisted of bimetal phosphorus trisulfides nanoneedles（Co_（0.5）Ni_（0.5）PS_3） and graphene nanosheets（denoted as Co_（0.5）Ni_（0.5）PS_3@G）. By choosing the Co_（0.5）Ni_（0.5）（OH）_2 nanoneedles as precursor, the Co_（0.5）Ni_（0.5）PS_3 derived by a simple solid-state transformation（SST） process was successfully attached onto the graphene surface.The as-prepared nanohybrids showed a superior cycling stability and rate performance for Li-ion storage.After cycling at a current density of 0.5 A g^（-1） for 500 cycles, the capacity are 456 mAh g^（-1）. Particularly,the capacity can reach 302 mAh g^（-1） at a current density of 10 A g^（-1）, which is 66.2% of the capacity at0.5 A g^（-1）. Even cycling at a current density of 50 A g^（-1）, the nanocomposite can still kept a capacity of 153 mAh g^（-1） with a capacity retention of 33.6%.

A new strategy for obtaining highly concentrated phosphorus recovery solution in biofilm phosphorus recovery process

Recovery of phosphorus(P)from wastewater is of great significance for alleviating the shortage of P resources.At present,the P recovery process is faced with the problem of excessive organic carbon consumption when obtaining a P-concentrated recovery solution.This study proposed a new strategy to obtain a more highly concentrated P recovery solution with minimal carbon consumption by strengthening the P storage capacity of the biofilm.A biofilm sequencing batch reactor(BSBR)process was modified to treat synthetic wastewater.The effect of the dissolved oxygen(DO)concentration on the P storage capacity of the biofilm was investigated at DO concentrations of DO 3.5 mg/L(P_(L))and DO 6.5 mg/L(P_(H)).The results showed a maximum P storage of 101.2 and 149.6 mg-P/g-mixed liquid suspended solids under the two conditions.Strengthening the P storage capacity of the biofilm resulted in a net increase in the P recovery rate,which was as high as 66.96%in a harvesting cycle,and total soluble P>220 mg/L in the P recovery solution was successfully achieved.Meanwhile,the carbon cost of P recovery in the BSBR was reduced to 41.57 g-chemical oxygen demand/gP,and the carbon utilization efficiency was enhanced.To highlight the new strategy,the P recovery performance of the BSBR was given and the relationship between P content and anaerobic P release was discussed.In addition,the changes in the microbial communities under P_(L) and P_(H) conditions were analyzed.

Interspecific competition effects on phosphorus accumulation by Hydrilla verticillata and Vallisneria natans

The competition between submersed plants has been recognized as an important factor influencing the structure of plant communities in shallow lakes. The ability of different species to take up and store nutrients from the surrounding ambience varies, and hence plant community structure might be expected to affect the cycling of nutrients in lake ecosystems. In this study, the uptake of phosphorus by Hydrilla verticillata and Vallisneria natans was studied and compared in monoculture and competitive mixed-culture plantings. Results showed that for both studied species the phosphorus concentrations of different tissues and of whole plants was unaffected by competition. However, the quantity of phosphorus accumulated by whole plants of 1-1. verticillata was significantly higher in mixture culture than in monoculture, while that of V. natans was lower in the mixed culture. The results indicated that 11. verticillata has a competitive advantage over V. natans, when the two species are grown in competition, and is able to accumulate a greater quantity of phosphorus.