Effects of factors such as slope, surface soil textuie, fertilization andcrop cover with different rainfall intensities on phosphorus (P) losses in farmland runoff of theDianchi Lake Watershed in Yunnan Province of Ch...Effects of factors such as slope, surface soil textuie, fertilization andcrop cover with different rainfall intensities on phosphorus (P) losses in farmland runoff of theDianchi Lake Watershed in Yunnan Province of China were studied through a rainfall simulation testusing a red soil, one of the most widely distributed soils of the study area. Results showed thatthe runoff concentrations of total phosphorus (TP) and P losses differed with the slope, beinghighest when the slope was 18 deg. At twodifferent rainfall intensities, the runoff TP and P losseshad a similar decreasing trend as the surface soil texture became coarser, therefore applying thegrit would decrease P in runofi from soils of farmland on slopes with heavier textures. With wheatas a crop cover the runoff TP concentrations and P losses were significantly lower than those of thebare soil. This showed that plant cover would greatly decrease P in runoff from the farmland of thestudy area. The TP concentration in runoff from the soil two days after fertilization doubled whencompared with that from the non-fertilized soil, indicating that fertilization could mean a dramaticrise in P runoff if irrigation or heavy rainfall occurred immediately after application and that nofertilization before a rain and no irrigation immediately after fertilization would reduce runoff Ploss from the farmland of the study area.展开更多
A Ca-P coating consisting of biodegradableβ-tricalcium phosphate[β-TCP,β-Ca3(PO4)2]accepted for medical application was coated on a biodegradable AZ31 alloy by chemical deposition to improve the corrosion resistanc...A Ca-P coating consisting of biodegradableβ-tricalcium phosphate[β-TCP,β-Ca3(PO4)2]accepted for medical application was coated on a biodegradable AZ31 alloy by chemical deposition to improve the corrosion resistance.The good bonding strength of the coating is obtained.The results show that the corrosion potential of the Ca-P coated AZ31 alloy increases significantly,and MG63 cells show good adherence,proliferation and differentiation on the surface of the coated alloy.The Ca-P coating might be an effective way to improve the surface bioactivity of magnesium alloys.展开更多
The purpose of this research is to investigate a biofilm system with trickling filter as a biological alternative process during low cost treatment connection with the possibility of reducing nutrients such as phospho...The purpose of this research is to investigate a biofilm system with trickling filter as a biological alternative process during low cost treatment connection with the possibility of reducing nutrients such as phosphorus. Given that nitrogen with phosphorus that are leading causes of algal bloom resulting in increased eutrophication or chemical nutrients are the basis of this document analysis. This increase in organisms results in less oxygen in water bodies and at times, slow decay leads many fresh water ponds, lakes and rivers. The process of eutrophication unfortunately tends to favor pollution and algae, which reduce the quality of the water. Kosovo has not a long tradition in the treatment of wastewater, especially in removing phosphorus, since the country has only a plant for wastewater treatment. The present plant is intended to protect the Klina river from eutrophication from wastewater discharged after treatment. This plant currently reduced phosphorus efficiently, but the goal of this paper is to increase the percentage of removal of phosphorus to 40% through trickling filters, presenting options for optimizing work on plant Skenderaj.展开更多
The bulk ring-opening polymerization （ROP） of ε-caprolactone （ε-CL） by various phosphoric acids using phenylmethanol as the initiator was conducted. 1, 1＇-bi-2-Naphthol （BINOL）-based phosphoric acid was found...The bulk ring-opening polymerization （ROP） of ε-caprolactone （ε-CL） by various phosphoric acids using phenylmethanol as the initiator was conducted. 1, 1＇-bi-2-Naphthol （BINOL）-based phosphoric acid was found to be an effective organocatalyst for ROP leading to polyesters at 90℃. The overall conversion to poly（ε-caprolactone） was more than 96% and poly（ε-caprolactone） with Mw of 8400 and polydispersity index of 1.13 was obtained. IH NMR spectra of oligomers demonstrated the quantitative incorporation of the protic initiator in the polymer chains and showed that transesterification reactions did not occur to a significant extent. The controlled polymerization was indicated by the linear relationships between the number-average molar mass and monomer conversion or monomer-to-initiator ratio. In addition, the present protocol provided an easy-to-handle, inexpensive and environmentally benign entry for the synthesis of biodegradable materials as well as polyesters for biomedical applications.展开更多
基金Project supported by the Applied and Basic Research Foundation of Yunnan Province (No. 1999C0011G).
文摘Effects of factors such as slope, surface soil textuie, fertilization andcrop cover with different rainfall intensities on phosphorus (P) losses in farmland runoff of theDianchi Lake Watershed in Yunnan Province of China were studied through a rainfall simulation testusing a red soil, one of the most widely distributed soils of the study area. Results showed thatthe runoff concentrations of total phosphorus (TP) and P losses differed with the slope, beinghighest when the slope was 18 deg. At twodifferent rainfall intensities, the runoff TP and P losseshad a similar decreasing trend as the surface soil texture became coarser, therefore applying thegrit would decrease P in runofi from soils of farmland on slopes with heavier textures. With wheatas a crop cover the runoff TP concentrations and P losses were significantly lower than those of thebare soil. This showed that plant cover would greatly decrease P in runoff from the farmland of thestudy area. The TP concentration in runoff from the soil two days after fertilization doubled whencompared with that from the non-fertilized soil, indicating that fertilization could mean a dramaticrise in P runoff if irrigation or heavy rainfall occurred immediately after application and that nofertilization before a rain and no irrigation immediately after fertilization would reduce runoff Ploss from the farmland of the study area.
基金Project(KGCX2-YW-207)supported by Chinese Academy of Sciences,ChinaProject(30970715)supported by National Natural Science Foundation of China
文摘A Ca-P coating consisting of biodegradableβ-tricalcium phosphate[β-TCP,β-Ca3(PO4)2]accepted for medical application was coated on a biodegradable AZ31 alloy by chemical deposition to improve the corrosion resistance.The good bonding strength of the coating is obtained.The results show that the corrosion potential of the Ca-P coated AZ31 alloy increases significantly,and MG63 cells show good adherence,proliferation and differentiation on the surface of the coated alloy.The Ca-P coating might be an effective way to improve the surface bioactivity of magnesium alloys.
文摘The purpose of this research is to investigate a biofilm system with trickling filter as a biological alternative process during low cost treatment connection with the possibility of reducing nutrients such as phosphorus. Given that nitrogen with phosphorus that are leading causes of algal bloom resulting in increased eutrophication or chemical nutrients are the basis of this document analysis. This increase in organisms results in less oxygen in water bodies and at times, slow decay leads many fresh water ponds, lakes and rivers. The process of eutrophication unfortunately tends to favor pollution and algae, which reduce the quality of the water. Kosovo has not a long tradition in the treatment of wastewater, especially in removing phosphorus, since the country has only a plant for wastewater treatment. The present plant is intended to protect the Klina river from eutrophication from wastewater discharged after treatment. This plant currently reduced phosphorus efficiently, but the goal of this paper is to increase the percentage of removal of phosphorus to 40% through trickling filters, presenting options for optimizing work on plant Skenderaj.
基金supported by the Fundamental Research Funds for the Central Universities (DL11CB06)
文摘The bulk ring-opening polymerization （ROP） of ε-caprolactone （ε-CL） by various phosphoric acids using phenylmethanol as the initiator was conducted. 1, 1＇-bi-2-Naphthol （BINOL）-based phosphoric acid was found to be an effective organocatalyst for ROP leading to polyesters at 90℃. The overall conversion to poly（ε-caprolactone） was more than 96% and poly（ε-caprolactone） with Mw of 8400 and polydispersity index of 1.13 was obtained. IH NMR spectra of oligomers demonstrated the quantitative incorporation of the protic initiator in the polymer chains and showed that transesterification reactions did not occur to a significant extent. The controlled polymerization was indicated by the linear relationships between the number-average molar mass and monomer conversion or monomer-to-initiator ratio. In addition, the present protocol provided an easy-to-handle, inexpensive and environmentally benign entry for the synthesis of biodegradable materials as well as polyesters for biomedical applications.
