Chinese education is like a large competitive game in the past time,with a lot of over-step learning and pre-emptive education increasing the extra—curricular pressure on primary and secondary school students day by ...Chinese education is like a large competitive game in the past time,with a lot of over-step learning and pre-emptive education increasing the extra—curricular pressure on primary and secondary school students day by day.In 2021,the national"double reduction"policy was implemented,and in 2022,the"Family Education Promotion Law of the People's Republic of China"was introduced.With the combined effect of"one government,one law",the status and role of family education have become more prominent,so it is of great practical significance to understand the education investment behavior of Chinese families.Therefore,this study is a case study of three students and their families from different schools in Weifang,Shandong Province in China.Through semi-structured interviews,this paper discusses the educational investment of well-off families after the implementation of the double reduction policy.The results show that art-related learning content dominates the education expenditure of well-off families after the implementation of the double-reducing policy,while cultural tutoring decreases.Becasue of(a)parents mainly want to cultivate their children's interests and hobbies or provide guidance for weak subjects;(b)the lack of understanding of the double reduction policy,leading to parents and students blindly follow the trend,increasing the pressure of students and parents'anxiety.This study focuses on the feelings of students and parents after the implementation of the double reduction policy,and attaches importance to the problems arising after the implementation of the policy.The findings are helpful to provide reference for future research on the educational investment of wealthy families after the implementation of the double reduction policy.展开更多
Under China’s“Double Reduction”policy,although the educational pressure has somewhat reduced,the mechanism of talent selection through examinations still exists,which means competition remains,leading to the intern...Under China’s“Double Reduction”policy,although the educational pressure has somewhat reduced,the mechanism of talent selection through examinations still exists,which means competition remains,leading to the internalization of education.This article analyzes the challenges faced by the“Double Reduction”policy from historical and current perspectives.The reasons for the internalization of education are examined and four recommendations for the further implementation of the“Double Reduction”policy are presented.展开更多
This essay delves into the pivotal role of mathematics within the context of STEAM(science,technology,engineering,arts,and mathematics)education under China’s“Double Reduction”policy.Amidst a shifting global educat...This essay delves into the pivotal role of mathematics within the context of STEAM(science,technology,engineering,arts,and mathematics)education under China’s“Double Reduction”policy.Amidst a shifting global education landscape that emphasizes holistic growth,policies such as the“Double Reduction”strategy underscore the significance of well-rounded development alongside academic excellence.By advocating for a balanced approach to education,the policy resonates with the principles of STEAM education,which seeks to cultivate versatile and innovative individuals.Mathematics,acting as a unifying force,connects disparate STEAM disciplines,fostering interdisciplinary collaboration and preparing students to thrive in a rapidly evolving,technology-driven world.This essay provides an in-depth exploration of the multifaceted role of mathematics in STEAM education,drawing on specific cases and scholarly references to highlight its contributions to creativity,critical thinking,and holistic development.展开更多
The impact of environmental regulation on technology innovation is a hot spot in current research where a large number of empirical studies are based on Porter Hypothesis(PH). However, there are still controversies in...The impact of environmental regulation on technology innovation is a hot spot in current research where a large number of empirical studies are based on Porter Hypothesis(PH). However, there are still controversies in academia about the establishment of "weak" and "narrow" versions of PH. Based on the panel data of application for patent of energy conservation and emission reduction(ECER) technology of Chinese city scale during 2008-2014, comprehensive energy price, pollutant emission, etc., mixed regression model and systematic generalized method of moments method were adopted, respectively,to study the impact of market-oriented and command-and-control policy tool on China's ECER technology innovation. The results show that the environmental regulation hindered the technological innovation in the immediate phase; however, it turned out to be positive in the first-lag phase. Hence, the establishment of "weak" PH is time-bounded. The command-and-control policy tool played a more positive role in promoting technological innovation in the first-lag phase than market-oriented policy tool. Therefore, "narrow" PH is not tenable. The reason is that the main participants of China's ECER technology innovation are state-owned companies and public institutions. Regionally speaking, the impact which command-and-control policy tool has on technological innovation at sight was nonsignificant in the eastern, the central, and the western regions of China whilst market-oriented policy tool had a negative effect. And market-oriented policy tool in the central region had strongest negative effect, which would diminish in the eastern region and become weakest in the western region. This was related to regional energy consumption level and the market economic vitality.展开更多
Insufficient assessment of emission reduction effects still exists in the carbon emission rights trading system,a major environmental regulation measure in China.Based on the data from the carbon trading pilot coverin...Insufficient assessment of emission reduction effects still exists in the carbon emission rights trading system,a major environmental regulation measure in China.Based on the data from the carbon trading pilot covering the years from 2007 to 2017,this study combined the synthetic control method with dynamic spatial Durbin model to comprehensively evaluate the spatial emission reduction effects of carbon trading policies.The results showed that:①The carbon trading policies promoted carbon emission reductions in the pilot regions,among which Tianjin and Hubei responded significantly,and also helped to suppress carbon emissions in the neighboring areas.②Long-term emission reduction effect from carbon emissions trading became gradually significant,while the indirect emission reduction effect was relatively weaker.③In term of reducing carbon emissions,the economic development channel played a key role,but it had a threat to the promotion of carbon emissions in the surrounding areas.Energy consumption was the main obstacle to the growth of carbon emissions.④In the long run,technological progress tended to become the key to the effective implementation of potential emission reduction effects of carbon trading policies.Based on the above findings,we suggest that the construction of a national carbon trading market should be promoted,the balanced development and orderly advancement of regional carbon trading markets should be paid attention to,the coordinated development of green economy as well as knowledge and technology exchange and cooperation among regions should be strengthened to form a low carbon development model among regions.展开更多
The use of energy conservation emission reduction policies to promote industrial restructuring and upgrading and thus facilitate energy conservation and emission reduction is one of the 10 important strategies of envi...The use of energy conservation emission reduction policies to promote industrial restructuring and upgrading and thus facilitate energy conservation and emission reduction is one of the 10 important strategies of environmental management in China. The use of energy conservation emission reduction policies to promote industrial restructuring and upgrading and thus facilitate energy conservation and emission reduction is one of the important strategies of environmental management in China. Based on the systematic collection of 1,195 energy conservation emission reduction policies, we discuss the influence of individual measure and measure synergy of energy conservation and emission reduction policies respectively. The results show that the energy conservation and emission reduction policies have a significant effect on the overall promotion of industrial upgrading. The financial measures and guidance measures have a positive impact;the financial measures and guidance measures have significantly positive effect; however, the administrative measures, fiscal tax measures, and other economic measures do the opposite; the positive effect of the synergy of guidance measures and financial measures is greater than the negative effect of considering only the synergy of fiscal tax measures and other economic measures, and significantly greater than the negative effect of the synergy of administrative measures, fiscal tax measures, and other economic measures. We should strengthen and emphasize the use of the measure that has positive effect on industrial structure restructuring and upgrading individually and synergistically.展开更多
Using the improved Energy-Environmental Version of the GTAP Model (GTAP-E) and the sixth version of emission database of non-CO2 greenhouse gases, we simulate the emission reduction potential of non-CO2 greenhouse gas...Using the improved Energy-Environmental Version of the GTAP Model (GTAP-E) and the sixth version of emission database of non-CO2 greenhouse gases, we simulate the emission reduction potential of non-CO2 greenhouse gases in China and its policy implications. The results show that at present, China is a country with the greatest emission of non-CO2 greenhouse gases in the world, and the emission will account for about 20% of the world's total emission in 2020. The proportion of emission of non-CO2 greenhouse gases from the agricultural sector reaches 73%. In the next 10 years, the emission of non-CO2 gases from cattle and sheep, industry and service industry will experience the highest growth rate; the growth rate of emission from service industry will be higher than that of emission from industry, and the emission from service industry will exceed that from industry after 2010. China can implement emission reduction policy of non-CO2 greenhouse gases to ease the international pressure of CO2 emission reduction. Although the high carbon tax collected can reduce considerable non-CO2 emission, there is little difference in policy efficiency between high carbon tax and low carbon tax. So, in the implementation of emission reduction carbon tax policy of non-CO2 gases, it is necessary to control the carbon tax at a low level.展开更多
Facilitating sulfur reduction reaction(SRR)is a promising pathway to tackle the polysulfide shuttle effect and enhance the electrochemical performance of lithium-sulfur(Li-S)batteries.Catalysts with a solo active site...Facilitating sulfur reduction reaction(SRR)is a promising pathway to tackle the polysulfide shuttle effect and enhance the electrochemical performance of lithium-sulfur(Li-S)batteries.Catalysts with a solo active site can reduce a reaction barrier of a certain transition-intermediate,but the linear scaling relationship between multi-intermediates still obstructs overall SRR.Herein,we construct tandem Co–O dual sites with accelerating SRR kinetics by loading highly dispersed cobalt sulfide clusters on halloysite.This catalyst features Co with upshifted d-orbital and O with downshifted p-orbital,which cooperatively adsorb long-chain polysulfide and dissociate an S–S bond,thus achieving both optimal adsorption–desorption strength and reduced conversion energy barrier of multi-intermediates in SRR.The Li-S coin batteries using the electrocatalyst endows a high specific capacity of 1224.3 m Ah g^(-1)at 0.2 C after 200cycles,and enhances cycling stability with a low-capacity decay rate of 0.03%per cycle at 1 C after1000 cycles.Moreover,the strategy of the tandem Co–O dual sites is further verified in a practical Li-S pouch battery that realizes 1014.1 m Ah g^(-1)for 100 cycles,which opens up a novel avenue for designing electrocatalysts to accelerate multi-step reactions.展开更多
The issues related to climate change such as depletion of energy resources and continuous high oil prices,global warming,and development of clean energy are adopted and discussed as a national agenda internationally.T...The issues related to climate change such as depletion of energy resources and continuous high oil prices,global warming,and development of clean energy are adopted and discussed as a national agenda internationally.To cope with these domestic and foreign energy and environmental problems actively,government must prepare prudently in methodology of greenhouse gas reduction.Especially,as energy consumption of buildings accounts for 26 of national consumption,plans to reduce energy consumption of buildings are needed.Each region has a unique nature of energy consumption or consumption patterns,thus an appropriate policy or goal to reduce greenhouse gas (GHG) should be selected.For this,effects on the current policies for GHG as well as nature of energy consumption of buildings should be analyzed.We analyzed quantitatively the effectiveness of policies to reduce GHG emission in public buildings.展开更多
'This year we will put more efforts in to tax cuts and fee reductions, to lower the VAT rate and contribution rate for basic retirement insurance. The surplus will amount to RMB 2 trillion,'Premier Li Keqiang ...'This year we will put more efforts in to tax cuts and fee reductions, to lower the VAT rate and contribution rate for basic retirement insurance. The surplus will amount to RMB 2 trillion,'Premier Li Keqiang said at the press conference during the Two Sessions.He also commented that all types of enterprises will benefit from the tax cuts and fee reductions policies and it will have a very high efficiency as the benefits will be delivered directly to market entities. The VAT cuts took effect from April 1 and pension insurance rate will be lower starting from May 1.展开更多
Increasing attention is being paid to the reduction of emissions from non-road mobile machinery,and many policies to promote the reduction have been established in countries and regions around the world,including the ...Increasing attention is being paid to the reduction of emissions from non-road mobile machinery,and many policies to promote the reduction have been established in countries and regions around the world,including the United States,Canada,the European Union,and China.This paper reviews these policies and analyzes two successful grant programs in the USA.Depending on the findings from the research,it is suggested that the Chinese government should tighten emission standards,introduce more financial subsidies,and strengthen supervision.展开更多
Recently,the Chinese government has published a new policy,called“Double Reduction”,addressing the problems of the workloads of the students under high school,and in the after-school training institution.Under this ...Recently,the Chinese government has published a new policy,called“Double Reduction”,addressing the problems of the workloads of the students under high school,and in the after-school training institution.Under this current situation,many after-school training institutions are confronting serious difficulties,even have to shut down and exit the market.Thus,it is of great significance to carefully analyze and discuss the influence on a certain case and its countermeasures.The article discusses the background of the“Double Reduction”policy,which is exam-oriented education,quality-oriented education,and education modernization.The article analyzes the influence and countermeasures of the“Double Reduction”on a medium size after-school English training institution in Wenzhou,Zhejiang,China.By using the method of interview,this article presents specific data about the influence and detailed plans of transition.展开更多
Based on Cognitive Style Theory,Oxford’s Speaking Learning Theory and Communicative Competence Theory,this paper adopts questionnaire method,uses Sternberg’s Thinking Style Inventory modified by Zhang Lifang,as well...Based on Cognitive Style Theory,Oxford’s Speaking Learning Theory and Communicative Competence Theory,this paper adopts questionnaire method,uses Sternberg’s Thinking Style Inventory modified by Zhang Lifang,as well as Oxford’s Learning Strategies Scale,and combines with the actual situation of junior high school students’oral learning to design the questionnaire of speaking learning strategies.Eighth graders of a junior middle school in Sichuan Province are randomly selected as the research object.The statistical tool SPSS23.0 is used to conduct the descriptive analysis and Pearson correlation analysis of the questionnaire results to explore the overall situation of junior high school students’thinking styles and the use of English-speaking learning strategies as well as their correlation.According to the research,junior high school students generally tend to executive style,liberal style,conservative style,legislative style,hierarchic style.The use of speaking learning strategies is at an average level.They tend to use memory speaking strategies,social speaking strategies,affective speaking strategies,and cognitive speaking strategies.As a whole,there is a relatively significant correlation between thinking styles and speaking learning strategies.Specifically,there is a partial correlation between thinking styles and speaking learning strategies.展开更多
The pyrolyzed carbon supported ferrum polypyrrole (Fe-N/C) catalysts are synthesized with or without selected dopants, p-toluenesulfonic acid (TsOH), by a facile thermal annealing approach at desired temperature f...The pyrolyzed carbon supported ferrum polypyrrole (Fe-N/C) catalysts are synthesized with or without selected dopants, p-toluenesulfonic acid (TsOH), by a facile thermal annealing approach at desired temperature for optimizing their activity for the oxygen reduction reaction (ORR) in O2-saturated 0.1 mol/L KOH solution. The electrochemical techniques such as cyclic voltammetry (CV) and rotating disk electrode (RDE) are employed with the Koutecky-Levich theory to quantitatively obtain the ORR kinetic constants and the reaction mechanisms. It is found that catalysts doped with TsOH show significantly improved ORR activity relative to the TsOH-free one. The average electron transfer numbers for the catalyzed ORR are determined to be 3.899 and 3.098, respectively, for the catalysts with and without TsOH-doping. The heat-treatment is found to be a necessary step for catalyst activity improvement, and the catalyst pyrolyzed at 600℃ gives the best ORR activity. An onset potential and the potential at the current density of -1.5 mA/cm2 for TsOH-doped catalyst after pyrolysis are 30 mV and 170 mV, which are more positive than those without pyrolized. Furthermore, the catalyst doped with TsOH shows higher tolerance to methanol compared with commercial Pt/C catalyst in 0.1 mol/L KOH. To understand this TsOH doping and pyrolyzed effect, X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) are used to characterize these catalysts in terms of their structure and composition. XPS results indicate that the pyrrolic-N groups are the most active sites, a finding that is supported by the correspondence between changes in pyridinic-N content and ORR activity that occur with changing temperature. Sulfur species are also structurally bound to carbon in the forms of C-Sn-C, an additional beneficial factor for the ORR.展开更多
It's been proved by theory and practice that taxation policy is one of the important means of realizing energy saving and emission reduction. The green taxation system in the Western countries has got better effec...It's been proved by theory and practice that taxation policy is one of the important means of realizing energy saving and emission reduction. The green taxation system in the Western countries has got better effects in energy saving and environmental protection. In the recent years, China has in succession released some taxation policies promoting energy saving and emission reduction, but still has a huge gap to meet the real needs of energy saving and emission reduction. By analyzing China's status quo of the polices of energy saving and emission reduction and drawing upon experiences of the developed countries about green taxation, this paper presents how to perfect ideas of China's energy saving and emission reduction taxation policies: adjusting taxes relevant to green taxation in the current taxation system, such as resource tax, consumer tax, and so on; collecting new environmental tax; perfecting the preferential taxation policies for the energy saving and environmental protection industries.展开更多
In this paper, an ultra-compact single negative(SNG) electric waveguided metamaterial(WG-MTM) is first investigated and used to reduce the mutual coupling in E & H planes of a dual-band microstrip antenna array. ...In this paper, an ultra-compact single negative(SNG) electric waveguided metamaterial(WG-MTM) is first investigated and used to reduce the mutual coupling in E & H planes of a dual-band microstrip antenna array. The proposed SNG electric WG-MTM unit cell is designed by etching two different symmetrical spiral lines on the ground, and has two stopbands operating at 1.86 GHz and 2.40 GHz. The circuit size is very compact, which is only λ_0/33.6 ×λ_0/15.1(where λ_0 is the wavelength at 1.86 GHz in free space). Taking advantage of the dual-stopband property of the proposed SNG electric WG-MTM, a dual-band microstrip antenna array operating at 1.86 GHz and 2.40 GHz with very low mutual coupling is designed by embedding a cross shaped array of the proposed SNG electric WG-MTM. The measured and simulated results of the designed dual-band antenna array are in good agreement with each other, indicating that the mutual coupling of the fabricated dual-band antenna array realizes 9.8/11.1 d B reductions in the H plane, 8.5/7.9 d B reductions in the E plane at1.86 GHz and 2.40 GHz, respectively. Besides, the distance of the antenna elements in the array is only 0.35 λ_0(where λ_0 is the wavelength at 1.86 GHz in free space). The proposed strategy is used for the first time to reduce the mutual coupling in E & H planes of the dual-band microstrip antenna array by using ultra-compact SNG electric WG-MTM.展开更多
Atomically-dispersed iron-based electrocatalysts are promising substitutes for noble metal electrocatalysts because of excellent performance in oxygen reduction reaction(ORR).Rationally modulating the local coordinati...Atomically-dispersed iron-based electrocatalysts are promising substitutes for noble metal electrocatalysts because of excellent performance in oxygen reduction reaction(ORR).Rationally modulating the local coordination environment of the Fe site and optimizing the binding energy of oxygen reduction intermediates are effective strategies to optimize ORR activity.Herein,we report a new method in which Ni is introduced to construct NiFe dual single atoms and iron nanoclusters loaded on the nitrogen-doped carbon with a highly porous structure.This design plays a synergistic role of dual single atoms and clusters,optimizes the 3d orbital and Fermi level of Fe,breaks the symmetrical structure of Fe-N_(4),and effectively improves the adsorption/desorption behavior of the oxygen-containing intermediates.Electrochemical tests show FeNCs/NiFeSAs-NC has an excellent intrinsic activity.Theoretical calculations show the oxygen-containing species on the Ni active site will move to the middle of NiFe(bridge site connection)after optimization and that the key step is OH desorption,with a reaction energy of 0.27 eV.The electron exchange between NiFe-N6 and Fe-cluster is very strong,further indicating the introduction of Ni species and Fe clusters has a regulatory effect on the electronic structure of Fe-N_(4).展开更多
Contingent Valuation Method(CVM) was used to investigate the Chinese public's willingness to pay(WTP) for a policy to reduce CO2 emissions. Face to face interviews were conducted to collect 1,653 valid questionnai...Contingent Valuation Method(CVM) was used to investigate the Chinese public's willingness to pay(WTP) for a policy to reduce CO2 emissions. Face to face interviews were conducted to collect 1,653 valid questionnaires from Beijing, Shanghai, Shandong province, and Fujian province. A model was constructed to understand the factors that influence WTP. The results indicate that the Chinese public is willing to pay CN 201.86 annually to support the policy of reducing greenhouse gas emissions. Participants from Beijing show the highest WTP, followed by participants from Fujian and Shandong, while those from Shanghai report the lowest WTP. The findings reveal that participants with higher income, higher satisfaction with their current life, and awareness of climate issues are willing to pay more for CO2 emissions reductions. In addition, those who are young, male and members of the Communist Party also indicate a higher WTP. The results imply that translating the public's willingness to protect climate into actions should be taken into account in China's low carbon policy. There is a need to consider the difference in degree of willingness, among different social groups, to pay for emissions reductions if the market-based mechanisms such as carbon tax were designed to facilitate emissions reductions.展开更多
This paper reflects the actual effect of China’s environmental protection tax by empirically analyzing the environmental effect of the emission fee, in order to provide reference for China’s environmental tax reform...This paper reflects the actual effect of China’s environmental protection tax by empirically analyzing the environmental effect of the emission fee, in order to provide reference for China’s environmental tax reform. Based on the traditional environmental “Kuznets” model, the factor of environmental tax is added to verify the effect of environmental governance of environmental tax. The results show that: 1) the improvement of sulfur dioxide emission charge standard can effectively inhibit industrial sulfur dioxide emission, which verifies the existence of environmental effect of pollution levy policies</span><span style="font-family:"">.</span><span style="font-family:""> 2) The improvement of sewage charge standard has better inhibitory effect on sulfur dioxide emission per unit GDP than on sulfur dioxide emission</span><span style="font-family:"">.</span><span style="font-family:""> 3) There is regional heterogeneity in the “emission reduction” effect of sulfur dioxide emission charges in the eastern, central and western regions of China. Pollutants should be taxed differently according to regional differences</span><span style="font-family:"">.</span><span style="font-family:""> 4) Economic growth and sulfur dioxide emission show an inverted “U” shape, China is still in the stage before the inflection point of EKC. Economic growth still takes environmental damage as the cost, and the “emission reduction” effect of technological progress is not ideal, which reveals the urgency of increasing technological development in the field of green environmental protection under the current situation.展开更多
Powered by electricity from renewable energies,electrochemical reduction of CO_(2)could not only efficiently alleviate the excess emission of CO_(2),but also produce many kinds of valuable chemical feedstocks.Among va...Powered by electricity from renewable energies,electrochemical reduction of CO_(2)could not only efficiently alleviate the excess emission of CO_(2),but also produce many kinds of valuable chemical feedstocks.Among various catalysts,single atom catalysts(SACs)have attracted much attention due to their high atom utilization efficiency and expressive catalytic performances.Additionally,SACs serve as an ideal platform for the investigation of complex reaction pathways and mechanisms thanks to their explicit active sites.In this review,the possible re-action pathways for the generation of various products(mainly C1 products for SACs)were firstly summarized.Then,recent progress of SACs for electrochemical reduction of CO_(2)was discussed in aspect of different central metal sites.As the most popular and efficient coordination modulation strategy,introducing heteroatom was then reviewed.Moreover,as an extension of SACs,the development of dual atom catalysts was also briefly discussed.At last,some issues and challenges regarding the SACs for CO_(2)reduction reaction(CO_(2)RR)were listed,followed by corresponding suggestions.展开更多
基金This paper is supported by the Macao Foundation's research project"An Empirical Study on the Training Standards for Innovative Talents in the Guangdong-Hong Kong-Macao Greater Bay Area"(MF2315)and the 2021 General Project of the 14th Five-Year Plan of Philosophy and Social Sciences of Guangdong Province of China(Number:GD21CJY08).
文摘Chinese education is like a large competitive game in the past time,with a lot of over-step learning and pre-emptive education increasing the extra—curricular pressure on primary and secondary school students day by day.In 2021,the national"double reduction"policy was implemented,and in 2022,the"Family Education Promotion Law of the People's Republic of China"was introduced.With the combined effect of"one government,one law",the status and role of family education have become more prominent,so it is of great practical significance to understand the education investment behavior of Chinese families.Therefore,this study is a case study of three students and their families from different schools in Weifang,Shandong Province in China.Through semi-structured interviews,this paper discusses the educational investment of well-off families after the implementation of the double reduction policy.The results show that art-related learning content dominates the education expenditure of well-off families after the implementation of the double-reducing policy,while cultural tutoring decreases.Becasue of(a)parents mainly want to cultivate their children's interests and hobbies or provide guidance for weak subjects;(b)the lack of understanding of the double reduction policy,leading to parents and students blindly follow the trend,increasing the pressure of students and parents'anxiety.This study focuses on the feelings of students and parents after the implementation of the double reduction policy,and attaches importance to the problems arising after the implementation of the policy.The findings are helpful to provide reference for future research on the educational investment of wealthy families after the implementation of the double reduction policy.
文摘Under China’s“Double Reduction”policy,although the educational pressure has somewhat reduced,the mechanism of talent selection through examinations still exists,which means competition remains,leading to the internalization of education.This article analyzes the challenges faced by the“Double Reduction”policy from historical and current perspectives.The reasons for the internalization of education are examined and four recommendations for the further implementation of the“Double Reduction”policy are presented.
文摘This essay delves into the pivotal role of mathematics within the context of STEAM(science,technology,engineering,arts,and mathematics)education under China’s“Double Reduction”policy.Amidst a shifting global education landscape that emphasizes holistic growth,policies such as the“Double Reduction”strategy underscore the significance of well-rounded development alongside academic excellence.By advocating for a balanced approach to education,the policy resonates with the principles of STEAM education,which seeks to cultivate versatile and innovative individuals.Mathematics,acting as a unifying force,connects disparate STEAM disciplines,fostering interdisciplinary collaboration and preparing students to thrive in a rapidly evolving,technology-driven world.This essay provides an in-depth exploration of the multifaceted role of mathematics in STEAM education,drawing on specific cases and scholarly references to highlight its contributions to creativity,critical thinking,and holistic development.
文摘The impact of environmental regulation on technology innovation is a hot spot in current research where a large number of empirical studies are based on Porter Hypothesis(PH). However, there are still controversies in academia about the establishment of "weak" and "narrow" versions of PH. Based on the panel data of application for patent of energy conservation and emission reduction(ECER) technology of Chinese city scale during 2008-2014, comprehensive energy price, pollutant emission, etc., mixed regression model and systematic generalized method of moments method were adopted, respectively,to study the impact of market-oriented and command-and-control policy tool on China's ECER technology innovation. The results show that the environmental regulation hindered the technological innovation in the immediate phase; however, it turned out to be positive in the first-lag phase. Hence, the establishment of "weak" PH is time-bounded. The command-and-control policy tool played a more positive role in promoting technological innovation in the first-lag phase than market-oriented policy tool. Therefore, "narrow" PH is not tenable. The reason is that the main participants of China's ECER technology innovation are state-owned companies and public institutions. Regionally speaking, the impact which command-and-control policy tool has on technological innovation at sight was nonsignificant in the eastern, the central, and the western regions of China whilst market-oriented policy tool had a negative effect. And market-oriented policy tool in the central region had strongest negative effect, which would diminish in the eastern region and become weakest in the western region. This was related to regional energy consumption level and the market economic vitality.
文摘Insufficient assessment of emission reduction effects still exists in the carbon emission rights trading system,a major environmental regulation measure in China.Based on the data from the carbon trading pilot covering the years from 2007 to 2017,this study combined the synthetic control method with dynamic spatial Durbin model to comprehensively evaluate the spatial emission reduction effects of carbon trading policies.The results showed that:①The carbon trading policies promoted carbon emission reductions in the pilot regions,among which Tianjin and Hubei responded significantly,and also helped to suppress carbon emissions in the neighboring areas.②Long-term emission reduction effect from carbon emissions trading became gradually significant,while the indirect emission reduction effect was relatively weaker.③In term of reducing carbon emissions,the economic development channel played a key role,but it had a threat to the promotion of carbon emissions in the surrounding areas.Energy consumption was the main obstacle to the growth of carbon emissions.④In the long run,technological progress tended to become the key to the effective implementation of potential emission reduction effects of carbon trading policies.Based on the above findings,we suggest that the construction of a national carbon trading market should be promoted,the balanced development and orderly advancement of regional carbon trading markets should be paid attention to,the coordinated development of green economy as well as knowledge and technology exchange and cooperation among regions should be strengthened to form a low carbon development model among regions.
文摘The use of energy conservation emission reduction policies to promote industrial restructuring and upgrading and thus facilitate energy conservation and emission reduction is one of the 10 important strategies of environmental management in China. The use of energy conservation emission reduction policies to promote industrial restructuring and upgrading and thus facilitate energy conservation and emission reduction is one of the important strategies of environmental management in China. Based on the systematic collection of 1,195 energy conservation emission reduction policies, we discuss the influence of individual measure and measure synergy of energy conservation and emission reduction policies respectively. The results show that the energy conservation and emission reduction policies have a significant effect on the overall promotion of industrial upgrading. The financial measures and guidance measures have a positive impact;the financial measures and guidance measures have significantly positive effect; however, the administrative measures, fiscal tax measures, and other economic measures do the opposite; the positive effect of the synergy of guidance measures and financial measures is greater than the negative effect of considering only the synergy of fiscal tax measures and other economic measures, and significantly greater than the negative effect of the synergy of administrative measures, fiscal tax measures, and other economic measures. We should strengthen and emphasize the use of the measure that has positive effect on industrial structure restructuring and upgrading individually and synergistically.
文摘Using the improved Energy-Environmental Version of the GTAP Model (GTAP-E) and the sixth version of emission database of non-CO2 greenhouse gases, we simulate the emission reduction potential of non-CO2 greenhouse gases in China and its policy implications. The results show that at present, China is a country with the greatest emission of non-CO2 greenhouse gases in the world, and the emission will account for about 20% of the world's total emission in 2020. The proportion of emission of non-CO2 greenhouse gases from the agricultural sector reaches 73%. In the next 10 years, the emission of non-CO2 gases from cattle and sheep, industry and service industry will experience the highest growth rate; the growth rate of emission from service industry will be higher than that of emission from industry, and the emission from service industry will exceed that from industry after 2010. China can implement emission reduction policy of non-CO2 greenhouse gases to ease the international pressure of CO2 emission reduction. Although the high carbon tax collected can reduce considerable non-CO2 emission, there is little difference in policy efficiency between high carbon tax and low carbon tax. So, in the implementation of emission reduction carbon tax policy of non-CO2 gases, it is necessary to control the carbon tax at a low level.
基金supported by the National Science Fund for Distinguished Young Scholars(51225403)the National Natural Science Foundation of China(52042403)+3 种基金the National Postdoctoral Program for Innovative Talents(BX2021276)the China Postdoctoral Science Foundation(2020M682519)the Strategic Priority Research Program of Central South University(ZLXD2017005)the“CUG Scholar"Scientific Research Funds at China University of Geosciences(Wuhan)(Project No.20222020110)。
文摘Facilitating sulfur reduction reaction(SRR)is a promising pathway to tackle the polysulfide shuttle effect and enhance the electrochemical performance of lithium-sulfur(Li-S)batteries.Catalysts with a solo active site can reduce a reaction barrier of a certain transition-intermediate,but the linear scaling relationship between multi-intermediates still obstructs overall SRR.Herein,we construct tandem Co–O dual sites with accelerating SRR kinetics by loading highly dispersed cobalt sulfide clusters on halloysite.This catalyst features Co with upshifted d-orbital and O with downshifted p-orbital,which cooperatively adsorb long-chain polysulfide and dissociate an S–S bond,thus achieving both optimal adsorption–desorption strength and reduced conversion energy barrier of multi-intermediates in SRR.The Li-S coin batteries using the electrocatalyst endows a high specific capacity of 1224.3 m Ah g^(-1)at 0.2 C after 200cycles,and enhances cycling stability with a low-capacity decay rate of 0.03%per cycle at 1 C after1000 cycles.Moreover,the strategy of the tandem Co–O dual sites is further verified in a practical Li-S pouch battery that realizes 1014.1 m Ah g^(-1)for 100 cycles,which opens up a novel avenue for designing electrocatalysts to accelerate multi-step reactions.
基金Funded by the National Research Foundation of Korea (NRF) of the Korea Government (MEST) (No.2011-0029867)
文摘The issues related to climate change such as depletion of energy resources and continuous high oil prices,global warming,and development of clean energy are adopted and discussed as a national agenda internationally.To cope with these domestic and foreign energy and environmental problems actively,government must prepare prudently in methodology of greenhouse gas reduction.Especially,as energy consumption of buildings accounts for 26 of national consumption,plans to reduce energy consumption of buildings are needed.Each region has a unique nature of energy consumption or consumption patterns,thus an appropriate policy or goal to reduce greenhouse gas (GHG) should be selected.For this,effects on the current policies for GHG as well as nature of energy consumption of buildings should be analyzed.We analyzed quantitatively the effectiveness of policies to reduce GHG emission in public buildings.
文摘'This year we will put more efforts in to tax cuts and fee reductions, to lower the VAT rate and contribution rate for basic retirement insurance. The surplus will amount to RMB 2 trillion,'Premier Li Keqiang said at the press conference during the Two Sessions.He also commented that all types of enterprises will benefit from the tax cuts and fee reductions policies and it will have a very high efficiency as the benefits will be delivered directly to market entities. The VAT cuts took effect from April 1 and pension insurance rate will be lower starting from May 1.
基金Environment and Conservation Fund:Environmental Research,Technology Demonstration and Conference of the Hong Kong Special Administrative Region,China(Project Ref.55/2019)。
文摘Increasing attention is being paid to the reduction of emissions from non-road mobile machinery,and many policies to promote the reduction have been established in countries and regions around the world,including the United States,Canada,the European Union,and China.This paper reviews these policies and analyzes two successful grant programs in the USA.Depending on the findings from the research,it is suggested that the Chinese government should tighten emission standards,introduce more financial subsidies,and strengthen supervision.
文摘Recently,the Chinese government has published a new policy,called“Double Reduction”,addressing the problems of the workloads of the students under high school,and in the after-school training institution.Under this current situation,many after-school training institutions are confronting serious difficulties,even have to shut down and exit the market.Thus,it is of great significance to carefully analyze and discuss the influence on a certain case and its countermeasures.The article discusses the background of the“Double Reduction”policy,which is exam-oriented education,quality-oriented education,and education modernization.The article analyzes the influence and countermeasures of the“Double Reduction”on a medium size after-school English training institution in Wenzhou,Zhejiang,China.By using the method of interview,this article presents specific data about the influence and detailed plans of transition.
文摘Based on Cognitive Style Theory,Oxford’s Speaking Learning Theory and Communicative Competence Theory,this paper adopts questionnaire method,uses Sternberg’s Thinking Style Inventory modified by Zhang Lifang,as well as Oxford’s Learning Strategies Scale,and combines with the actual situation of junior high school students’oral learning to design the questionnaire of speaking learning strategies.Eighth graders of a junior middle school in Sichuan Province are randomly selected as the research object.The statistical tool SPSS23.0 is used to conduct the descriptive analysis and Pearson correlation analysis of the questionnaire results to explore the overall situation of junior high school students’thinking styles and the use of English-speaking learning strategies as well as their correlation.According to the research,junior high school students generally tend to executive style,liberal style,conservative style,legislative style,hierarchic style.The use of speaking learning strategies is at an average level.They tend to use memory speaking strategies,social speaking strategies,affective speaking strategies,and cognitive speaking strategies.As a whole,there is a relatively significant correlation between thinking styles and speaking learning strategies.Specifically,there is a partial correlation between thinking styles and speaking learning strategies.
基金supported by the National Natural Science Foundation of China(91223202)the International Science&Technology Cooperation Program of China(No.2011DFA73410)+1 种基金Tsinghua University Initiative Scientific Research Program(No.20101081907)the National Key Basic Research Program of China-973 Program(No.2011CB013102)
文摘The pyrolyzed carbon supported ferrum polypyrrole (Fe-N/C) catalysts are synthesized with or without selected dopants, p-toluenesulfonic acid (TsOH), by a facile thermal annealing approach at desired temperature for optimizing their activity for the oxygen reduction reaction (ORR) in O2-saturated 0.1 mol/L KOH solution. The electrochemical techniques such as cyclic voltammetry (CV) and rotating disk electrode (RDE) are employed with the Koutecky-Levich theory to quantitatively obtain the ORR kinetic constants and the reaction mechanisms. It is found that catalysts doped with TsOH show significantly improved ORR activity relative to the TsOH-free one. The average electron transfer numbers for the catalyzed ORR are determined to be 3.899 and 3.098, respectively, for the catalysts with and without TsOH-doping. The heat-treatment is found to be a necessary step for catalyst activity improvement, and the catalyst pyrolyzed at 600℃ gives the best ORR activity. An onset potential and the potential at the current density of -1.5 mA/cm2 for TsOH-doped catalyst after pyrolysis are 30 mV and 170 mV, which are more positive than those without pyrolized. Furthermore, the catalyst doped with TsOH shows higher tolerance to methanol compared with commercial Pt/C catalyst in 0.1 mol/L KOH. To understand this TsOH doping and pyrolyzed effect, X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) are used to characterize these catalysts in terms of their structure and composition. XPS results indicate that the pyrrolic-N groups are the most active sites, a finding that is supported by the correspondence between changes in pyridinic-N content and ORR activity that occur with changing temperature. Sulfur species are also structurally bound to carbon in the forms of C-Sn-C, an additional beneficial factor for the ORR.
基金supported by the Key Research Project of Shandong Social Science Planning(Grant No. 07JDB071)
文摘It's been proved by theory and practice that taxation policy is one of the important means of realizing energy saving and emission reduction. The green taxation system in the Western countries has got better effects in energy saving and environmental protection. In the recent years, China has in succession released some taxation policies promoting energy saving and emission reduction, but still has a huge gap to meet the real needs of energy saving and emission reduction. By analyzing China's status quo of the polices of energy saving and emission reduction and drawing upon experiences of the developed countries about green taxation, this paper presents how to perfect ideas of China's energy saving and emission reduction taxation policies: adjusting taxes relevant to green taxation in the current taxation system, such as resource tax, consumer tax, and so on; collecting new environmental tax; perfecting the preferential taxation policies for the energy saving and environmental protection industries.
基金Project supported by the National Natural Science Foundation of China(Grant No.61372034)
文摘In this paper, an ultra-compact single negative(SNG) electric waveguided metamaterial(WG-MTM) is first investigated and used to reduce the mutual coupling in E & H planes of a dual-band microstrip antenna array. The proposed SNG electric WG-MTM unit cell is designed by etching two different symmetrical spiral lines on the ground, and has two stopbands operating at 1.86 GHz and 2.40 GHz. The circuit size is very compact, which is only λ_0/33.6 ×λ_0/15.1(where λ_0 is the wavelength at 1.86 GHz in free space). Taking advantage of the dual-stopband property of the proposed SNG electric WG-MTM, a dual-band microstrip antenna array operating at 1.86 GHz and 2.40 GHz with very low mutual coupling is designed by embedding a cross shaped array of the proposed SNG electric WG-MTM. The measured and simulated results of the designed dual-band antenna array are in good agreement with each other, indicating that the mutual coupling of the fabricated dual-band antenna array realizes 9.8/11.1 d B reductions in the H plane, 8.5/7.9 d B reductions in the E plane at1.86 GHz and 2.40 GHz, respectively. Besides, the distance of the antenna elements in the array is only 0.35 λ_0(where λ_0 is the wavelength at 1.86 GHz in free space). The proposed strategy is used for the first time to reduce the mutual coupling in E & H planes of the dual-band microstrip antenna array by using ultra-compact SNG electric WG-MTM.
基金supported by the National Natural Science Foundation of China(No.22202020)the Natural Science Foundation of Changzhou City(No.CJ20210134).
文摘Atomically-dispersed iron-based electrocatalysts are promising substitutes for noble metal electrocatalysts because of excellent performance in oxygen reduction reaction(ORR).Rationally modulating the local coordination environment of the Fe site and optimizing the binding energy of oxygen reduction intermediates are effective strategies to optimize ORR activity.Herein,we report a new method in which Ni is introduced to construct NiFe dual single atoms and iron nanoclusters loaded on the nitrogen-doped carbon with a highly porous structure.This design plays a synergistic role of dual single atoms and clusters,optimizes the 3d orbital and Fermi level of Fe,breaks the symmetrical structure of Fe-N_(4),and effectively improves the adsorption/desorption behavior of the oxygen-containing intermediates.Electrochemical tests show FeNCs/NiFeSAs-NC has an excellent intrinsic activity.Theoretical calculations show the oxygen-containing species on the Ni active site will move to the middle of NiFe(bridge site connection)after optimization and that the key step is OH desorption,with a reaction energy of 0.27 eV.The electron exchange between NiFe-N6 and Fe-cluster is very strong,further indicating the introduction of Ni species and Fe clusters has a regulatory effect on the electronic structure of Fe-N_(4).
基金supported by the Foundation of the Humanities and Social Science, Ministry of Education of the People’s Republic of China (No. 09YJA790119)
文摘Contingent Valuation Method(CVM) was used to investigate the Chinese public's willingness to pay(WTP) for a policy to reduce CO2 emissions. Face to face interviews were conducted to collect 1,653 valid questionnaires from Beijing, Shanghai, Shandong province, and Fujian province. A model was constructed to understand the factors that influence WTP. The results indicate that the Chinese public is willing to pay CN 201.86 annually to support the policy of reducing greenhouse gas emissions. Participants from Beijing show the highest WTP, followed by participants from Fujian and Shandong, while those from Shanghai report the lowest WTP. The findings reveal that participants with higher income, higher satisfaction with their current life, and awareness of climate issues are willing to pay more for CO2 emissions reductions. In addition, those who are young, male and members of the Communist Party also indicate a higher WTP. The results imply that translating the public's willingness to protect climate into actions should be taken into account in China's low carbon policy. There is a need to consider the difference in degree of willingness, among different social groups, to pay for emissions reductions if the market-based mechanisms such as carbon tax were designed to facilitate emissions reductions.
文摘This paper reflects the actual effect of China’s environmental protection tax by empirically analyzing the environmental effect of the emission fee, in order to provide reference for China’s environmental tax reform. Based on the traditional environmental “Kuznets” model, the factor of environmental tax is added to verify the effect of environmental governance of environmental tax. The results show that: 1) the improvement of sulfur dioxide emission charge standard can effectively inhibit industrial sulfur dioxide emission, which verifies the existence of environmental effect of pollution levy policies</span><span style="font-family:"">.</span><span style="font-family:""> 2) The improvement of sewage charge standard has better inhibitory effect on sulfur dioxide emission per unit GDP than on sulfur dioxide emission</span><span style="font-family:"">.</span><span style="font-family:""> 3) There is regional heterogeneity in the “emission reduction” effect of sulfur dioxide emission charges in the eastern, central and western regions of China. Pollutants should be taxed differently according to regional differences</span><span style="font-family:"">.</span><span style="font-family:""> 4) Economic growth and sulfur dioxide emission show an inverted “U” shape, China is still in the stage before the inflection point of EKC. Economic growth still takes environmental damage as the cost, and the “emission reduction” effect of technological progress is not ideal, which reveals the urgency of increasing technological development in the field of green environmental protection under the current situation.
文摘Powered by electricity from renewable energies,electrochemical reduction of CO_(2)could not only efficiently alleviate the excess emission of CO_(2),but also produce many kinds of valuable chemical feedstocks.Among various catalysts,single atom catalysts(SACs)have attracted much attention due to their high atom utilization efficiency and expressive catalytic performances.Additionally,SACs serve as an ideal platform for the investigation of complex reaction pathways and mechanisms thanks to their explicit active sites.In this review,the possible re-action pathways for the generation of various products(mainly C1 products for SACs)were firstly summarized.Then,recent progress of SACs for electrochemical reduction of CO_(2)was discussed in aspect of different central metal sites.As the most popular and efficient coordination modulation strategy,introducing heteroatom was then reviewed.Moreover,as an extension of SACs,the development of dual atom catalysts was also briefly discussed.At last,some issues and challenges regarding the SACs for CO_(2)reduction reaction(CO_(2)RR)were listed,followed by corresponding suggestions.