Athens, a metropolis characterized by agglutination and compactness, but at the same time facing numerous urban and transport issues, saw its population swell during the 20th century which led to extensive urbanizatio...Athens, a metropolis characterized by agglutination and compactness, but at the same time facing numerous urban and transport issues, saw its population swell during the 20th century which led to extensive urbanization phenomena. This continued urbanization increases profoundly all urban activities with transportation being the key driver in energy consumption. Theories for sustainable cities prerequisite are the integration of a number of acts in order to reduce energy consumption, with mobility being the first consideration among others. The aim of this paper is to critically explore implemented policies and plans as well as forthcoming strategic plans in terms of sustainable mobility as imposed in large scale regeneration plans in contemporary Athens. Research focuses on strategic interventions since the 1980s, such as the Athenian Daktylios （ring road for circulation management） and its later adjustments, the upcoming pedestrianization and unification of the commercial triangle and its subsequent tram line extension as well as the notable implementation of the metropolitan cycling network. Moreover, the discussion takes into consideration the implications of the Greek economic crisis in mobility choices, as aimless travels have been reduced to a minimum, several cars have been abandoned and cyclists seem to tentatively claim some space in the urban environment. What will likely be the next day in the Athenian historic centre？ Considering the transformations that are expected in the immediate future, this research paper explores their potential to enhance urban environment, reduce climate change impacts and amplify resilience.展开更多
Portable electrochemical synthesis of H_(2)O_(2),which is widely used for disinfection,sterilization,and waste treatment,has attracted increasing attention.However,low atomic utilization efficiency and by-product disp...Portable electrochemical synthesis of H_(2)O_(2),which is widely used for disinfection,sterilization,and waste treatment,has attracted increasing attention.However,low atomic utilization efficiency and by-product disposal during the synthesis of electrocatalysts are inevitable.Based on the advantages of single-atom catalysts(SACs)towards H_(2)O_(2)synthesis via a 2e−transfer oxygen reduction reaction,this work presents the synthesis of ZnNC SACs as excellent oxygen reduction catalysts with high atomic use efficiency and almost no generated waste by using formamide and metal powder as precursors.The ZnNC SACs exhibit H_(2)O_(2)selectivity exceeding 80%when working continuously for 10,000 s.The synthetic strategy described in this paper is intended to be used as a supplement to the synthesis of metal-nitrogen-carbon SACs with high atomic utilization efficiency and low waste generation for environmental and chemical applications.展开更多
文摘Athens, a metropolis characterized by agglutination and compactness, but at the same time facing numerous urban and transport issues, saw its population swell during the 20th century which led to extensive urbanization phenomena. This continued urbanization increases profoundly all urban activities with transportation being the key driver in energy consumption. Theories for sustainable cities prerequisite are the integration of a number of acts in order to reduce energy consumption, with mobility being the first consideration among others. The aim of this paper is to critically explore implemented policies and plans as well as forthcoming strategic plans in terms of sustainable mobility as imposed in large scale regeneration plans in contemporary Athens. Research focuses on strategic interventions since the 1980s, such as the Athenian Daktylios （ring road for circulation management） and its later adjustments, the upcoming pedestrianization and unification of the commercial triangle and its subsequent tram line extension as well as the notable implementation of the metropolitan cycling network. Moreover, the discussion takes into consideration the implications of the Greek economic crisis in mobility choices, as aimless travels have been reduced to a minimum, several cars have been abandoned and cyclists seem to tentatively claim some space in the urban environment. What will likely be the next day in the Athenian historic centre？ Considering the transformations that are expected in the immediate future, this research paper explores their potential to enhance urban environment, reduce climate change impacts and amplify resilience.
基金financially supported by the National Key Research and Development Program of China (2018YFA0702002)the National Natural Science Foundation of China (21935001, 22101015, 22175012 and 22005022)+3 种基金the Royal Society and Newton Fund through Newton Advanced Fellowship award (NAFR1191294)the Program for Changjiang Scholars and Innovation Research Team in the University (IRT1205)the Fundamental Research Funds for the Central Universities, Beijing Natural Science Foundation (2214062)the S&T Program of Hebei (21344601D)
文摘Portable electrochemical synthesis of H_(2)O_(2),which is widely used for disinfection,sterilization,and waste treatment,has attracted increasing attention.However,low atomic utilization efficiency and by-product disposal during the synthesis of electrocatalysts are inevitable.Based on the advantages of single-atom catalysts(SACs)towards H_(2)O_(2)synthesis via a 2e−transfer oxygen reduction reaction,this work presents the synthesis of ZnNC SACs as excellent oxygen reduction catalysts with high atomic use efficiency and almost no generated waste by using formamide and metal powder as precursors.The ZnNC SACs exhibit H_(2)O_(2)selectivity exceeding 80%when working continuously for 10,000 s.The synthetic strategy described in this paper is intended to be used as a supplement to the synthesis of metal-nitrogen-carbon SACs with high atomic utilization efficiency and low waste generation for environmental and chemical applications.
