Large-scale pig-raising can discharge a great deal of wastewater,which contains high content of organic matter,ammonia nitrogen and suspended solids.The improper treatment of the piggery wastewater can lead to serious...Large-scale pig-raising can discharge a great deal of wastewater,which contains high content of organic matter,ammonia nitrogen and suspended solids.The improper treatment of the piggery wastewater can lead to serious environmental problems. As a liquid fertilizer,piggery wastewater is relatively low in fertilizer efficiency and high in transportation cost,so it is very necessary to treat it in situ. Energy plants have the advantages of rapid growth,large biomass,strong tillering ability and developed root system. Therefore,energy plants can be used to absorb and transform the pollutants( like nitrogen and phosphorus) in piggery wastewater into the components of plants,as well as form the rhizosphere environment which is conducive to microbial growth,so as to enhance the effects of nitrogen and phosphorus removal. The obtained energy plants can be recycled as the raw materials for biogas to increase the production of biogas,which brings economic benefits while solving the environmental problems caused by piggery wastewater.展开更多
To analyze the resonance mechanism of a photovoltaic(PV)power plant,a simplified impedance model of the PV power plant is first established.The structure of the PV power plant is then introduced,and the reason for the...To analyze the resonance mechanism of a photovoltaic(PV)power plant,a simplified impedance model of the PV power plant is first established.The structure of the PV power plant is then introduced,and the reason for the resonance is obtained by analyzing the on-site situation and measured data of the PV power plant.Finally,a simple and effective solution is proposed based on the structure of the PV power plant and its existing facilities.The results of the engineering experiments and the stable operation of the PV power plant verify the effectiveness of the proposed method.展开更多
Per-and polyfluoroalkyl substances(PFASs)can be taken up and bioaccumulated in plants,but the toxic mechanisms of PFASs on wetland plants are still unclear.In present study,the toxic influences of perfluorooctane sulf...Per-and polyfluoroalkyl substances(PFASs)can be taken up and bioaccumulated in plants,but the toxic mechanisms of PFASs on wetland plants are still unclear.In present study,the toxic influences of perfluorooctane sulfonate(PFOS)on Eichhornia crassipes(E.crassipes)and Cy perus alternifolius(C.alternifolius)in a vertical-sub surface-flow constructed wetland were evaluated.The results showed that E.crassipes was more tolerant to PFOS stress than C.alternifolius,and the growth and chlorophyll synthesis of the two plants were promoted by low concentration(<0.1 mg/L)of PFOS,and the chlorophyll synthesis was inhibited by high concentration(10 mg/L)of PFOS but the growth did not change obviously.The catalase activity and malondialdehyde content in the leaves of the two plants increased,peroxidase activity decreased under exposure to high concentrations of PFOS,and superoxide dismutase activity did not change.Under PFOS stress,the membrane of plant leaves and the cell structure of the two wetland plants were destroyed,and the mitochondrial contour of root cells became incomplete.Tanscriptomic analysis showed that the expression levels of genes related to cell wall formation,the cell apoptosis pathway,material synthesis,and metabolism in the plants were changed by PFOS.Analysis in fluorogenic quantitative real time polymerase chain reaction(RT-qPCR)also confirmed that the photosynthesis system of E.crassipes was inhibited,while that of C.alternifolius was promoted.展开更多
A vertical-flow constructed wetland(VFCW)was used to treat simulated domestic sewage containing perfluorooctane sulfonate(PFOS).The removal rate of PFOS in the domestic sewage was 93%–98%,through soil adsorption and ...A vertical-flow constructed wetland(VFCW)was used to treat simulated domestic sewage containing perfluorooctane sulfonate(PFOS).The removal rate of PFOS in the domestic sewage was 93%–98%,through soil adsorption and plant uptake,suggesting that VFCWs can remove PFOS efficiently from wastewater.The removal of PFOS in the VFCW was dependent on soil adsorption and plant uptake;moreover,the percentage of soil adsorption was 61%–89%,and was higher than that of the plants uptake(5%–31%).The absorption capacity of Eichhornia crassipes(E.crassipes)(1186.71 mg/kg)was higher than that of Cyperus alternifolius(C.alternifolius)(162.77 mg/kg)under 10 mg/L PFOS,and the transfer factor of PFOS in E.crassipes and C.alternifolius was 0.04 and 0.58,respectively,indicating that PFOS is not easily translocated to leaves from roots of wetland plants;moreover,uptake of PFOS by E.crassipes was more than that of C.alternifolius because the biomass of E.crassipes was more than that of C.alternifolius and the roots of E.crassipes can take up PFOS directly from wastewater while C.alternifolius needs to do so via its roots in the soil.The concentration of 10 mg/L PFOS had an obvious inhibitory effect on the removal rate of total nitrogen,total phosphorus,chemical oxygen demand,and ammonia nitrogen in the VFCW,which decreased by 15%,10%,10%and 12%,respectively.Dosing with PFOS in the wastewater reduced the bacterial richness but increased the diversity in soil because PFOS stimulated the growth of PFOS-tolerant strains.展开更多
基金Supported by the National Natural Science Foundation of China(41263006,2014BAC04B02)the Fund Project of Science and Technology Department of Jiangxi Province(20124ACB01200,20122BBG70086,20133ACF60005)the Fund Project of Jiangxi Academy of Sciences(gankeyuan(2013)No.19-06,2012-YYB-01,2013-XTPH1-14,2013H003)
文摘Large-scale pig-raising can discharge a great deal of wastewater,which contains high content of organic matter,ammonia nitrogen and suspended solids.The improper treatment of the piggery wastewater can lead to serious environmental problems. As a liquid fertilizer,piggery wastewater is relatively low in fertilizer efficiency and high in transportation cost,so it is very necessary to treat it in situ. Energy plants have the advantages of rapid growth,large biomass,strong tillering ability and developed root system. Therefore,energy plants can be used to absorb and transform the pollutants( like nitrogen and phosphorus) in piggery wastewater into the components of plants,as well as form the rhizosphere environment which is conducive to microbial growth,so as to enhance the effects of nitrogen and phosphorus removal. The obtained energy plants can be recycled as the raw materials for biogas to increase the production of biogas,which brings economic benefits while solving the environmental problems caused by piggery wastewater.
基金Supported by the International Science and Technology Cooperation Program of China(2018YFE0125300)the National Natural Science Foundation of China(52061130217)+2 种基金the Innovative Construction Program of Hunan Province of China(2019RS1016)the 111 Project of China(B17016)the Excellent Innovation Youth Program of Changsha of China(KQ2009037).
文摘To analyze the resonance mechanism of a photovoltaic(PV)power plant,a simplified impedance model of the PV power plant is first established.The structure of the PV power plant is then introduced,and the reason for the resonance is obtained by analyzing the on-site situation and measured data of the PV power plant.Finally,a simple and effective solution is proposed based on the structure of the PV power plant and its existing facilities.The results of the engineering experiments and the stable operation of the PV power plant verify the effectiveness of the proposed method.
基金supported by the National Key Research and Development Program of China(No.2018YFC1803100)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Per-and polyfluoroalkyl substances(PFASs)can be taken up and bioaccumulated in plants,but the toxic mechanisms of PFASs on wetland plants are still unclear.In present study,the toxic influences of perfluorooctane sulfonate(PFOS)on Eichhornia crassipes(E.crassipes)and Cy perus alternifolius(C.alternifolius)in a vertical-sub surface-flow constructed wetland were evaluated.The results showed that E.crassipes was more tolerant to PFOS stress than C.alternifolius,and the growth and chlorophyll synthesis of the two plants were promoted by low concentration(<0.1 mg/L)of PFOS,and the chlorophyll synthesis was inhibited by high concentration(10 mg/L)of PFOS but the growth did not change obviously.The catalase activity and malondialdehyde content in the leaves of the two plants increased,peroxidase activity decreased under exposure to high concentrations of PFOS,and superoxide dismutase activity did not change.Under PFOS stress,the membrane of plant leaves and the cell structure of the two wetland plants were destroyed,and the mitochondrial contour of root cells became incomplete.Tanscriptomic analysis showed that the expression levels of genes related to cell wall formation,the cell apoptosis pathway,material synthesis,and metabolism in the plants were changed by PFOS.Analysis in fluorogenic quantitative real time polymerase chain reaction(RT-qPCR)also confirmed that the photosynthesis system of E.crassipes was inhibited,while that of C.alternifolius was promoted.
基金This research was financially supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘A vertical-flow constructed wetland(VFCW)was used to treat simulated domestic sewage containing perfluorooctane sulfonate(PFOS).The removal rate of PFOS in the domestic sewage was 93%–98%,through soil adsorption and plant uptake,suggesting that VFCWs can remove PFOS efficiently from wastewater.The removal of PFOS in the VFCW was dependent on soil adsorption and plant uptake;moreover,the percentage of soil adsorption was 61%–89%,and was higher than that of the plants uptake(5%–31%).The absorption capacity of Eichhornia crassipes(E.crassipes)(1186.71 mg/kg)was higher than that of Cyperus alternifolius(C.alternifolius)(162.77 mg/kg)under 10 mg/L PFOS,and the transfer factor of PFOS in E.crassipes and C.alternifolius was 0.04 and 0.58,respectively,indicating that PFOS is not easily translocated to leaves from roots of wetland plants;moreover,uptake of PFOS by E.crassipes was more than that of C.alternifolius because the biomass of E.crassipes was more than that of C.alternifolius and the roots of E.crassipes can take up PFOS directly from wastewater while C.alternifolius needs to do so via its roots in the soil.The concentration of 10 mg/L PFOS had an obvious inhibitory effect on the removal rate of total nitrogen,total phosphorus,chemical oxygen demand,and ammonia nitrogen in the VFCW,which decreased by 15%,10%,10%and 12%,respectively.Dosing with PFOS in the wastewater reduced the bacterial richness but increased the diversity in soil because PFOS stimulated the growth of PFOS-tolerant strains.
