Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in Chi...Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.展开更多
The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few stud...The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few studies have investigated the sources and properties of DOC in riparian zones.A total of 34 soil samples were collected across four riparian buffer zones(Zones A-D) on Chongming Island,China.The vertical distributions of soil organic carbon(SOC) and DOC,fluorescence excitation-emission matrix(EEM) spectra of DOC and the optical indices,including fluorescence index(FI),index of recent autochthonous contribution(BIX),and humification index(HIX),were measured across the riparian environment to investigate the sources and fluorescence properties of DOC.The results showed that SOC stored in the surface soil(0-30 cm) accounted for 40%of the total soil profile SOC.The DOC accumulated in Zones A-C,which accounted for 5%of the SOC.The fluorescence EEM spectra of DOC showed that DOC contained humic-like and protein-like substances,which were mainly derived from recent plant debris by microbes.A large amount of humic-like substances were sorbed to minerals in the surface soil(0-30 cm).In addition,the riparian topography and soil physico-chemical properties(pH,EC and moisture) dictated the transformation and transport of DOC.The results suggested that EEMs could reveal the source of DOC in riparian soil systems,and that optical indices were complementary tools that revealed the characteristics of soil DOC and provided supplemental evidence about DOC sources.展开更多
为了让更多肿瘤患者更早接受疗效突出、安全性良好的创新药物治疗,以单臂试验(single arm trial,SAT)数据支持新药注册成为一种加速新药上市的手段。境外已有多个治疗慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)的新药通过...为了让更多肿瘤患者更早接受疗效突出、安全性良好的创新药物治疗,以单臂试验(single arm trial,SAT)数据支持新药注册成为一种加速新药上市的手段。境外已有多个治疗慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)的新药通过单臂研究获得批准,我国药品监管机构收到的关于通过单臂研究支持CLL新药上市的沟通交流也不断增加。本文借鉴境外以单臂研究批准CLL新药的经验,结合我国监管机构对单臂研究支持抗肿瘤药上市的基本要求,分析CLL的疾病特点和临床需求,提出以单臂研究支持CLL新药注册的审评考虑。展开更多
基金Project supported by the National Key Basic Research Support Foundation of China (No. 2002CB412303)the Natural Science Foundation of Jiangsu Province (No. KB2004115)
文摘Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment of China(Nos.2011ZX07303-001 and 2014ZX07303-003)the State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences(No.Y412201426)
文摘The migration of soil dissolved organic carbon(DOC) from terrestrial to aquatic environments has important impacts on the adjacent water quality and the transport of organic and inorganic contaminants.However,few studies have investigated the sources and properties of DOC in riparian zones.A total of 34 soil samples were collected across four riparian buffer zones(Zones A-D) on Chongming Island,China.The vertical distributions of soil organic carbon(SOC) and DOC,fluorescence excitation-emission matrix(EEM) spectra of DOC and the optical indices,including fluorescence index(FI),index of recent autochthonous contribution(BIX),and humification index(HIX),were measured across the riparian environment to investigate the sources and fluorescence properties of DOC.The results showed that SOC stored in the surface soil(0-30 cm) accounted for 40%of the total soil profile SOC.The DOC accumulated in Zones A-C,which accounted for 5%of the SOC.The fluorescence EEM spectra of DOC showed that DOC contained humic-like and protein-like substances,which were mainly derived from recent plant debris by microbes.A large amount of humic-like substances were sorbed to minerals in the surface soil(0-30 cm).In addition,the riparian topography and soil physico-chemical properties(pH,EC and moisture) dictated the transformation and transport of DOC.The results suggested that EEMs could reveal the source of DOC in riparian soil systems,and that optical indices were complementary tools that revealed the characteristics of soil DOC and provided supplemental evidence about DOC sources.
文摘为了让更多肿瘤患者更早接受疗效突出、安全性良好的创新药物治疗,以单臂试验(single arm trial,SAT)数据支持新药注册成为一种加速新药上市的手段。境外已有多个治疗慢性淋巴细胞白血病(chronic lymphocytic leukemia,CLL)的新药通过单臂研究获得批准,我国药品监管机构收到的关于通过单臂研究支持CLL新药上市的沟通交流也不断增加。本文借鉴境外以单臂研究批准CLL新药的经验,结合我国监管机构对单臂研究支持抗肿瘤药上市的基本要求,分析CLL的疾病特点和临床需求,提出以单臂研究支持CLL新药注册的审评考虑。
