Decarbonization is a critical issue for peaking CO_(2) emissions of energy-intensive industries,such as the iron and steel industry.The decarbonization options of China’s ironmaking and steelmaking sector were discus...Decarbonization is a critical issue for peaking CO_(2) emissions of energy-intensive industries,such as the iron and steel industry.The decarbonization options of China’s ironmaking and steelmaking sector were discussed based on a systematic three-dimensional low-carbon analysis from the aspects of resource utilization(Y),energy utilization(Q),and energy cleanliness which is evaluated by a process general emission factor(PGEF)on all the related processes,including the current blast furnace(BF)-basic oxygen furnace(BOF)integrated process and the specific sub-processes,as well as the electric arc furnace(EAF)process,typical direct reduction(DR)process,and smelting reduction(SR)process.The study indicates that the three-dimensional aspects,particularly the energy structure,should be comprehensively considered to quantitatively evaluate the decarbonization road map based on novel technologies or processes.Promoting scrap utilization(improvement of Y)and the substitution of carbon-based energy(improvement of PGEF)in particular is critical.In terms of process scale,promoting the development of the scrap-based EAF or DR-EAF process is highly encouraged because of their lower PGEF.The three-dimensional method is expected to extend to other processes or industries,such as the cement production and thermal electricity generation industries.展开更多
A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the ...A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the design considerations and implementation of the PT beamline from a systematic viewpoint.Design considerations covering beam optics and the influence of high-order aberrations,beam energy/intensity modulation,and beam orbit correction are described.In addition to the technical implementation of the main beamline components and subsystems,including the energy degrader,fast kicker,beamline magnets,beam diagnostic system,and beamline control system are introduced.展开更多
我国能源活动碳排放占总碳排放85%以上,研究能源活动碳排放的变化规律对于实现碳达峰碳中和目标具有重要意义.首先,采用对数平均迪氏分解法(logarithmic mean Divisia index,LMDI)对1995—2017年我国能源消费碳排放变化的影响因素进行分...我国能源活动碳排放占总碳排放85%以上,研究能源活动碳排放的变化规律对于实现碳达峰碳中和目标具有重要意义.首先,采用对数平均迪氏分解法(logarithmic mean Divisia index,LMDI)对1995—2017年我国能源消费碳排放变化的影响因素进行分解,从经济规模、产业结构、能源强度、能源结构、能源价格、人均可支配收入、人口规模这7个方面,模型给出了相关因素对一、二、三产业和居民部门碳排放变化的贡献.结果表明,对于3个产业部门,经济增长是碳排放增长的首要驱动力,而技术进步带来的能源强度下降、产业结构优化和能源消费结构改善呈现负效应,且产业结构优化和能源结构清洁化的作用越来越显著.对于居民部门,人均可支配收入是居民部门碳排放增长的推动力,而能源价格呈现明显的负效应.其次,设计了3种情景,运用可拓展的随机性的环境影响评估模型(stochastic impacts by regression population,affluence and technology,STIRPAT)对2030年我国能源碳排放进行预测,在以实现碳达峰为目标的低碳情景中,我国能源碳排放有望于2025—2029年实现达峰,峰值水平为101亿~110亿t.最后,为实现碳达峰碳中和目标,建议以构建中国能源互联网为基础平台,实施"清洁替代"和"电能替代",推进能源转型.展开更多
基金supported by the State Key Laboratory of Advanced Metallurgy,China(Project Code:41603006).
文摘Decarbonization is a critical issue for peaking CO_(2) emissions of energy-intensive industries,such as the iron and steel industry.The decarbonization options of China’s ironmaking and steelmaking sector were discussed based on a systematic three-dimensional low-carbon analysis from the aspects of resource utilization(Y),energy utilization(Q),and energy cleanliness which is evaluated by a process general emission factor(PGEF)on all the related processes,including the current blast furnace(BF)-basic oxygen furnace(BOF)integrated process and the specific sub-processes,as well as the electric arc furnace(EAF)process,typical direct reduction(DR)process,and smelting reduction(SR)process.The study indicates that the three-dimensional aspects,particularly the energy structure,should be comprehensively considered to quantitatively evaluate the decarbonization road map based on novel technologies or processes.Promoting scrap utilization(improvement of Y)and the substitution of carbon-based energy(improvement of PGEF)in particular is critical.In terms of process scale,promoting the development of the scrap-based EAF or DR-EAF process is highly encouraged because of their lower PGEF.The three-dimensional method is expected to extend to other processes or industries,such as the cement production and thermal electricity generation industries.
基金the National Key Research and Development Program of China(No.2016YFC0105305)the National Natural Science Foundation of China(11975107)the Program for HUST Academic Frontier Youth Team.
文摘A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the design considerations and implementation of the PT beamline from a systematic viewpoint.Design considerations covering beam optics and the influence of high-order aberrations,beam energy/intensity modulation,and beam orbit correction are described.In addition to the technical implementation of the main beamline components and subsystems,including the energy degrader,fast kicker,beamline magnets,beam diagnostic system,and beamline control system are introduced.
文摘我国能源活动碳排放占总碳排放85%以上,研究能源活动碳排放的变化规律对于实现碳达峰碳中和目标具有重要意义.首先,采用对数平均迪氏分解法(logarithmic mean Divisia index,LMDI)对1995—2017年我国能源消费碳排放变化的影响因素进行分解,从经济规模、产业结构、能源强度、能源结构、能源价格、人均可支配收入、人口规模这7个方面,模型给出了相关因素对一、二、三产业和居民部门碳排放变化的贡献.结果表明,对于3个产业部门,经济增长是碳排放增长的首要驱动力,而技术进步带来的能源强度下降、产业结构优化和能源消费结构改善呈现负效应,且产业结构优化和能源结构清洁化的作用越来越显著.对于居民部门,人均可支配收入是居民部门碳排放增长的推动力,而能源价格呈现明显的负效应.其次,设计了3种情景,运用可拓展的随机性的环境影响评估模型(stochastic impacts by regression population,affluence and technology,STIRPAT)对2030年我国能源碳排放进行预测,在以实现碳达峰为目标的低碳情景中,我国能源碳排放有望于2025—2029年实现达峰,峰值水平为101亿~110亿t.最后,为实现碳达峰碳中和目标,建议以构建中国能源互联网为基础平台,实施"清洁替代"和"电能替代",推进能源转型.
