The implementation of ultra-low emission(ULE)limits(SO_(2):35 mg/m3,NOx:50 mg/m3,PM:10 mg/m3)promoted the development of flue gas treatment technologies in China.Pollutant control technology development for Chinese co...The implementation of ultra-low emission(ULE)limits(SO_(2):35 mg/m3,NOx:50 mg/m3,PM:10 mg/m3)promoted the development of flue gas treatment technologies in China.Pollutant control technology development for Chinese coal-fired power plants was summarized and an analysis of the applicability and cost of pollutant control technologies was conducted.Detailed data were collected from 30 ultra-low emission coal-fired units across China.Based on a cost analysis model,the average unit power generation incremental costs were 0.0144and 0.0095 CNY/(kW·hr)for SO_(2)and NOx control technologies,respectively.The unit power generation incremental cost of twin spray tower technology was 7.2%higher than that of dual-loop spray tower technology.The effect of key parameters on operating cost was analyzed.The unit power generation incremental cost increased because of increments in the electricity price for SO_(2)control technology and the price of the reductant in NOx control technology.With high sulfur content or NOx concentration,the unit power generation incremental cost caused by pollutant control increased,whereas the unit pollutant abatement cost decreased.However,the annual operating hours or load increased,thereby leading to a decline in unit power generation incremental cost and unit pollutant abatement cost.展开更多
Sexual and spatio-temporal variations have been observed in the life history parameters of many aquatic species and their causes have been related to harvesting pressure and environmental changes.This study aims to ex...Sexual and spatio-temporal variations have been observed in the life history parameters of many aquatic species and their causes have been related to harvesting pressure and environmental changes.This study aims to explore sexual,spatial and temporal variation in the growth and maturity through weight-at-length,length-at-age,and maturity-at-length relationships for Lake Erie Walleye(Sander vitreus)as a case to test some hypotheses.Hypotheses on whether harvest pressure and environmental changes(both local and global scale)caused the temporal changes of these life history traits were further diagnosed.Sexual and spatio-temporal variations in these life history traits were formulated using mixed-effects models.Our study found that geographic basin,sex,year and cohort all have substantial effects on the growth and maturity of Walleye based on survey data from 1989 to 2015.Multiple factors including water supply of Lake Erie,temperature,fishing pressure of Walleye,and global climate factors were found to correlate with the temporal variations of growth and maturity of Walleye significantly.Our findings should contribute to the future interpretation of Walleye life history variations and population dynamics.The methodology constructed in this study could be applied to explore the heterogeneity and impacting factors for other species in aquatic ecosystems.展开更多
基金supported by the National Key Research and Development Program of China(No.2019YFC0214803)Zhejiang Provincial Natural Science Foundation of China(No.LQ21D050002).
文摘The implementation of ultra-low emission(ULE)limits(SO_(2):35 mg/m3,NOx:50 mg/m3,PM:10 mg/m3)promoted the development of flue gas treatment technologies in China.Pollutant control technology development for Chinese coal-fired power plants was summarized and an analysis of the applicability and cost of pollutant control technologies was conducted.Detailed data were collected from 30 ultra-low emission coal-fired units across China.Based on a cost analysis model,the average unit power generation incremental costs were 0.0144and 0.0095 CNY/(kW·hr)for SO_(2)and NOx control technologies,respectively.The unit power generation incremental cost of twin spray tower technology was 7.2%higher than that of dual-loop spray tower technology.The effect of key parameters on operating cost was analyzed.The unit power generation incremental cost increased because of increments in the electricity price for SO_(2)control technology and the price of the reductant in NOx control technology.With high sulfur content or NOx concentration,the unit power generation incremental cost caused by pollutant control increased,whereas the unit pollutant abatement cost decreased.However,the annual operating hours or load increased,thereby leading to a decline in unit power generation incremental cost and unit pollutant abatement cost.
基金supported by the National Basic Research Program of China(973 Project2015CB755602)+3 种基金the National Natural Science Foundation of China(61721092,61890953,31871088,and 81871082)Key-Area Research and Development Program of Guangdong Province(2019B030335001)CAMS Innovation Fund for Medical Sciences(2019-I2M-5-014)the Director Fund of Wuhan National Laboratory for Optoelectronics。
文摘Sexual and spatio-temporal variations have been observed in the life history parameters of many aquatic species and their causes have been related to harvesting pressure and environmental changes.This study aims to explore sexual,spatial and temporal variation in the growth and maturity through weight-at-length,length-at-age,and maturity-at-length relationships for Lake Erie Walleye(Sander vitreus)as a case to test some hypotheses.Hypotheses on whether harvest pressure and environmental changes(both local and global scale)caused the temporal changes of these life history traits were further diagnosed.Sexual and spatio-temporal variations in these life history traits were formulated using mixed-effects models.Our study found that geographic basin,sex,year and cohort all have substantial effects on the growth and maturity of Walleye based on survey data from 1989 to 2015.Multiple factors including water supply of Lake Erie,temperature,fishing pressure of Walleye,and global climate factors were found to correlate with the temporal variations of growth and maturity of Walleye significantly.Our findings should contribute to the future interpretation of Walleye life history variations and population dynamics.The methodology constructed in this study could be applied to explore the heterogeneity and impacting factors for other species in aquatic ecosystems.