A stacked Si/SiO_(x)/C composite anode material with carbon-coated structure was prepared by sol-gel method combined with carbothermal reduction using organic silicon.The results of X-ray diffractometry, scanning elec...A stacked Si/SiO_(x)/C composite anode material with carbon-coated structure was prepared by sol-gel method combined with carbothermal reduction using organic silicon.The results of X-ray diffractometry, scanning electron microscopy, and elemental analysis show that the Si/SiO_(x)/C material is a secondary particle with a porous micronanostructure, and the presence of nanometer silicon does not affect the carbothermal reduction and carbon coating.Electrochemical test results indicate that the specific capacity and first coulombic efficiency of SiO_(x)/C composite with nanometer silicon can be increased to 1 946.05 mAh/g and 76.49%,respectively.The reversible specific capacity of Si/SiO_(x)/C material blended with graphite is 749.69 mAh/g after 100 cycles at a current density of 0.1 C,and the capacity retention rate is up to 89.03%.Therefore, the composite has excellent electrochemical cycle stability.展开更多
The Northern Junggar Basin experienced extensive subduction and a complex tectono-magmatic evolution during the Late Paleozoic,resulting in a heterogeneous distribution of volcanic rocks in the Junggar Basin.In this s...The Northern Junggar Basin experienced extensive subduction and a complex tectono-magmatic evolution during the Late Paleozoic,resulting in a heterogeneous distribution of volcanic rocks in the Junggar Basin.In this study,the Carboniferous tectono-magmatic evolution of the northern Luliang arc was described by exploring the petrography and geochemistry of Carboniferous volcanic rocks collected from well Y-2 and outcrop WW' in the northern Luliang Uplift.The distribution,types,and formation ages of these volcanic rocks were characterized and the volcanic sequence in well Y-1 was divided into upper and lower parts according to vertical variations in selected geochemical data.Then the petrogenesis and tectonic settings of different volcanic rocks were evaluated and this was used to infer the tectonomagmatic evolution of the northern Luliang arc during the Carboniferous.The results indicate that:(1) Carboniferous high-K calc-alkali andesite-dacite associations are distributed in the west of the northern Luliang Uplift,and Lower Carboniferous calc-alkali basalt-dacite-rhyolite assemblages are preserved in its east.(2) The intermediateacid volcanic rocks in wells Y-1 and Y-2 were derived from calc-alkali basaltic magma through melting of the juvenile lower crust,and geochemical variations indicate increasing addition of slab melting in a subduction-related arc environment.The bimodal volcanic rocks from outcrop WW' were derived from lithospheric underplating of basaltic magma in an intra-arc extensional setting.(3) The closure of the eastern Keramaili Oceanic basin occurred before the Early Carboniferous,and the tectono-magmatic difference between the east and the west of the northern Luliang Uplift appeared before the Carboniferous period.展开更多
As global climate governance moves into the implementation phase,the integration of bluetech and clean energy has emerged as a key driver of green transition.On the occasion of the 50th anniversary of China-EU diploma...As global climate governance moves into the implementation phase,the integration of bluetech and clean energy has emerged as a key driver of green transition.On the occasion of the 50th anniversary of China-EU diplomatic relations,China and Portugal have built a multi-level cooperation framework in the“ocean+clean energy”domain,leveraging complementary resource endowments,technological synergies,and policy alignment.展开更多
This paper systematically reviews the institutional evolution of the China-ASEAN Free Trade Area(CAFTA),from its inception in 2002 and full establishment in 2010,through the CAFTA 2.0 upgrade in 2015,to the substantiv...This paper systematically reviews the institutional evolution of the China-ASEAN Free Trade Area(CAFTA),from its inception in 2002 and full establishment in 2010,through the CAFTA 2.0 upgrade in 2015,to the substantive conclusion of CAFTA 3.0 negotiations in 2024.It highlights the key institutional innovations along this trajectory and examines the structural complementarities between China and ASEAN in terms of clean energy resources and industrial capabilities.Based on this foundation,the paper develops a“policy-technology-capital”analytical framework to explain the transition of regional clean energy cooperation from initial resource-industry complementarity toward deeper institution-market integration.Guided by this framework,the study proposes a roadmap and concrete policy recommendations for regional cooperation through 2030.These include:aligning regional emissions targets and renewable energy share goals;establishing a mutual recognition system for green standards;building a digitalized green supply chain and carbon traceability platform;designing cross-border green finance corridors;and constructing integrated electricity-hydrogen-storage corridors in synergy with the Belt and Road Initiative.The study concludes that,if effectively implemented,these measures could raise the regional share of renewable electricity generation to over 30%by 2030.China and ASEAN would then be well positioned to lead in forming a low-carbon,interconnected,and shared regional energy community,offering a replicable and scalable model for low-carbon transition across the Global South.展开更多
This paper examines the technological advancements,policy support,and market trends in the global hydrogen energy market by 2025.As technological innovation and international cooperation advance,hydrogen energy will a...This paper examines the technological advancements,policy support,and market trends in the global hydrogen energy market by 2025.As technological innovation and international cooperation advance,hydrogen energy will achieve commercial applications in transportation,industry,and energy storage,becoming a significant driving force in the global energy transition.展开更多
In the context of the global energy transition,the oil and gas industry faces the urgent challenge of green transformation.This article examines the ESG(Environmental,Social,and Governance)trajectory and sustainable d...In the context of the global energy transition,the oil and gas industry faces the urgent challenge of green transformation.This article examines the ESG(Environmental,Social,and Governance)trajectory and sustainable development within the oil and gas industry.It delves into the current application of the ESG framework within the industry,evaluates policy standards,and assesses the opportunities and challenges confronting it.展开更多
To accelerate the large-scale integration of renewable energy and support the strategic goals of“carbon peaking and carbon neutrality,”High Voltage Direct Current(HVDC)transmission technology has made significant br...To accelerate the large-scale integration of renewable energy and support the strategic goals of“carbon peaking and carbon neutrality,”High Voltage Direct Current(HVDC)transmission technology has made significant breakthroughs.Among the various approaches,a hybrid DC transmission system that combines a line-commutated converter(LCC)and a voltage source converter(VSC)retains the inherent fault self-clearing capability of the LCC topology while mitigating the risk of commutation failure when connected to a weak grid.In this paper,based on the harmonic generation mechanisms of hybrid DC transmission systems,an improved 3-pulse harmonic source model of the LCC and a dynamic phase-sequence harmonic analysis model of the VSC are developed.The integrated harmonic model demonstrates strong adaptability in accurately calculating DC-side harmonics under the influence of power imbalances and background harmonics.Based on this model,the fundamental characteristics of DC-side harmonics in hybrid DC transmission systems are analyzed.To mitigate harmonic effects,this paper proposes an LCLC-trap2 high-order filter structure with parallel RC damping circuits and a co-optimized design of filter parameters.Finally,a±500 kV hybrid DC transmission systemismodeled using theMATLAB/Simulink platform,and the harmonic filtering performances of the conventional LC filter,the Butterworth filter,and the proposed filter are simulated and compared.The results verify that the proposed filter offers superior performance in suppressing low-order harmonics under nonideal operating conditions.展开更多
Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O cr...Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O crystal plane orientation and the corresponding adsorbed ^(*)CO species.Herein,we constructed high-index crystal planes(311) in Cu_(2)O(CO-Cu_(2)O) via a facile self-selective CO-induced strategy under a CO atmosphere,which was verified by high-resolution transmission electron microscopy(HR-TEM) and atomic force microscopy(AFM) results.By exploiting the high surface energy of the high index crystal planes,^(*)CO species are stabilized in CO-Cu_(2)O during CO_(2)RR,resulting in exceptional catalytic performance for CO_(2)-to-C_(2)products.In situ infrared spectroscopy revealed that both atop-type(^(*)CO_(atop)) and hollow-type(^(*)CO_(hollow)) adsorption of ^(*)CO species occurred on the CO-Cu_(2)O.The asymmetric C-C coupling energy barrier between ^(*)CO_(atop) and ^(*)CO_(hollow) in(311) crystal plane decreases by 47.8 % compared to the symmetric coupling of ^(*)CO_(atop) in conventional(100) crystal planes.Consequently,the Faradaic efficiency of C_(2) products generated with CO-Cu_(2)O was increased by as high as 100 % compared to that with pristine Cu_(2)O.展开更多
Since 2009,ultra-high voltage(UHV)transmission technology has been promoted and applied in China.Over the years,with the accumulation of experience in the construction and operation of UHV projects and the continuous ...Since 2009,ultra-high voltage(UHV)transmission technology has been promoted and applied in China.Over the years,with the accumulation of experience in the construction and operation of UHV projects and the continuous deepening of scientific and technological innovation,UHV technology and key equipment have made great progress.This paper introduces the main achievements of UHV technology innovation from various perspectives including electromagnetic environment,overvoltage and insulation coordination,external insulation and major equipment such as converter transformers,converter valves and gas-insulated transmission lines(GIL).展开更多
From the view of geographic location, climate and population status, this paper makes a comparative study of the economy structure, transport system, energy supply and carbon emissions among a few cities, especially b...From the view of geographic location, climate and population status, this paper makes a comparative study of the economy structure, transport system, energy supply and carbon emissions among a few cities, especially between Beijing and London, two mega-cities in the world. The developed tertiary industry, consummate transport system and low-carbon energy supply system in London can be referenced to assist Beijing in establishing a low-carbon development pathway. The difference in the statistical coverage of population between these two cities also brings about the divergence of energy consumption per capita and CO2 emissions per capita between them.展开更多
文摘A stacked Si/SiO_(x)/C composite anode material with carbon-coated structure was prepared by sol-gel method combined with carbothermal reduction using organic silicon.The results of X-ray diffractometry, scanning electron microscopy, and elemental analysis show that the Si/SiO_(x)/C material is a secondary particle with a porous micronanostructure, and the presence of nanometer silicon does not affect the carbothermal reduction and carbon coating.Electrochemical test results indicate that the specific capacity and first coulombic efficiency of SiO_(x)/C composite with nanometer silicon can be increased to 1 946.05 mAh/g and 76.49%,respectively.The reversible specific capacity of Si/SiO_(x)/C material blended with graphite is 749.69 mAh/g after 100 cycles at a current density of 0.1 C,and the capacity retention rate is up to 89.03%.Therefore, the composite has excellent electrochemical cycle stability.
基金financially supported by the National Natural Science Foundation of China (Nos.41802182 and 42072192)Open fund of Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process of the Ministry of Education,China University of Mining and Technology (No.2018-004)+1 种基金A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institution (PAPD)China Scholarship Council。
文摘The Northern Junggar Basin experienced extensive subduction and a complex tectono-magmatic evolution during the Late Paleozoic,resulting in a heterogeneous distribution of volcanic rocks in the Junggar Basin.In this study,the Carboniferous tectono-magmatic evolution of the northern Luliang arc was described by exploring the petrography and geochemistry of Carboniferous volcanic rocks collected from well Y-2 and outcrop WW' in the northern Luliang Uplift.The distribution,types,and formation ages of these volcanic rocks were characterized and the volcanic sequence in well Y-1 was divided into upper and lower parts according to vertical variations in selected geochemical data.Then the petrogenesis and tectonic settings of different volcanic rocks were evaluated and this was used to infer the tectonomagmatic evolution of the northern Luliang arc during the Carboniferous.The results indicate that:(1) Carboniferous high-K calc-alkali andesite-dacite associations are distributed in the west of the northern Luliang Uplift,and Lower Carboniferous calc-alkali basalt-dacite-rhyolite assemblages are preserved in its east.(2) The intermediateacid volcanic rocks in wells Y-1 and Y-2 were derived from calc-alkali basaltic magma through melting of the juvenile lower crust,and geochemical variations indicate increasing addition of slab melting in a subduction-related arc environment.The bimodal volcanic rocks from outcrop WW' were derived from lithospheric underplating of basaltic magma in an intra-arc extensional setting.(3) The closure of the eastern Keramaili Oceanic basin occurred before the Early Carboniferous,and the tectono-magmatic difference between the east and the west of the northern Luliang Uplift appeared before the Carboniferous period.
文摘As global climate governance moves into the implementation phase,the integration of bluetech and clean energy has emerged as a key driver of green transition.On the occasion of the 50th anniversary of China-EU diplomatic relations,China and Portugal have built a multi-level cooperation framework in the“ocean+clean energy”domain,leveraging complementary resource endowments,technological synergies,and policy alignment.
文摘This paper systematically reviews the institutional evolution of the China-ASEAN Free Trade Area(CAFTA),from its inception in 2002 and full establishment in 2010,through the CAFTA 2.0 upgrade in 2015,to the substantive conclusion of CAFTA 3.0 negotiations in 2024.It highlights the key institutional innovations along this trajectory and examines the structural complementarities between China and ASEAN in terms of clean energy resources and industrial capabilities.Based on this foundation,the paper develops a“policy-technology-capital”analytical framework to explain the transition of regional clean energy cooperation from initial resource-industry complementarity toward deeper institution-market integration.Guided by this framework,the study proposes a roadmap and concrete policy recommendations for regional cooperation through 2030.These include:aligning regional emissions targets and renewable energy share goals;establishing a mutual recognition system for green standards;building a digitalized green supply chain and carbon traceability platform;designing cross-border green finance corridors;and constructing integrated electricity-hydrogen-storage corridors in synergy with the Belt and Road Initiative.The study concludes that,if effectively implemented,these measures could raise the regional share of renewable electricity generation to over 30%by 2030.China and ASEAN would then be well positioned to lead in forming a low-carbon,interconnected,and shared regional energy community,offering a replicable and scalable model for low-carbon transition across the Global South.
文摘This paper examines the technological advancements,policy support,and market trends in the global hydrogen energy market by 2025.As technological innovation and international cooperation advance,hydrogen energy will achieve commercial applications in transportation,industry,and energy storage,becoming a significant driving force in the global energy transition.
基金supported by“the Fundamental Research Funds for Zhejiang’s Provincial Universities and Colleges,Project No.:2024ZX26”。
文摘In the context of the global energy transition,the oil and gas industry faces the urgent challenge of green transformation.This article examines the ESG(Environmental,Social,and Governance)trajectory and sustainable development within the oil and gas industry.It delves into the current application of the ESG framework within the industry,evaluates policy standards,and assesses the opportunities and challenges confronting it.
基金funded by the Natural Science Foundation of Chongqing(CSTB2023NSCQMSX0279)the Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN202201119).
文摘To accelerate the large-scale integration of renewable energy and support the strategic goals of“carbon peaking and carbon neutrality,”High Voltage Direct Current(HVDC)transmission technology has made significant breakthroughs.Among the various approaches,a hybrid DC transmission system that combines a line-commutated converter(LCC)and a voltage source converter(VSC)retains the inherent fault self-clearing capability of the LCC topology while mitigating the risk of commutation failure when connected to a weak grid.In this paper,based on the harmonic generation mechanisms of hybrid DC transmission systems,an improved 3-pulse harmonic source model of the LCC and a dynamic phase-sequence harmonic analysis model of the VSC are developed.The integrated harmonic model demonstrates strong adaptability in accurately calculating DC-side harmonics under the influence of power imbalances and background harmonics.Based on this model,the fundamental characteristics of DC-side harmonics in hybrid DC transmission systems are analyzed.To mitigate harmonic effects,this paper proposes an LCLC-trap2 high-order filter structure with parallel RC damping circuits and a co-optimized design of filter parameters.Finally,a±500 kV hybrid DC transmission systemismodeled using theMATLAB/Simulink platform,and the harmonic filtering performances of the conventional LC filter,the Butterworth filter,and the proposed filter are simulated and compared.The results verify that the proposed filter offers superior performance in suppressing low-order harmonics under nonideal operating conditions.
基金the financial support from the National Natural Science Foundation of China (Nos.U23A20677,22022610 and 52400137)"Pioneer" and "Leading Goose" R&D Program of Zhejiang (Nos.2022C03146 and 2023C03017)+2 种基金China Postdoctoral Science Foundation (No.2024T170805)Zhejiang Provincial Natural Science Foundation of China (No.LDT23E06015B06)the support of the Research Computing Center in College of Chemical and Biological Engineering at Zhejiang University for assistance with the calculations。
文摘Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O crystal plane orientation and the corresponding adsorbed ^(*)CO species.Herein,we constructed high-index crystal planes(311) in Cu_(2)O(CO-Cu_(2)O) via a facile self-selective CO-induced strategy under a CO atmosphere,which was verified by high-resolution transmission electron microscopy(HR-TEM) and atomic force microscopy(AFM) results.By exploiting the high surface energy of the high index crystal planes,^(*)CO species are stabilized in CO-Cu_(2)O during CO_(2)RR,resulting in exceptional catalytic performance for CO_(2)-to-C_(2)products.In situ infrared spectroscopy revealed that both atop-type(^(*)CO_(atop)) and hollow-type(^(*)CO_(hollow)) adsorption of ^(*)CO species occurred on the CO-Cu_(2)O.The asymmetric C-C coupling energy barrier between ^(*)CO_(atop) and ^(*)CO_(hollow) in(311) crystal plane decreases by 47.8 % compared to the symmetric coupling of ^(*)CO_(atop) in conventional(100) crystal planes.Consequently,the Faradaic efficiency of C_(2) products generated with CO-Cu_(2)O was increased by as high as 100 % compared to that with pristine Cu_(2)O.
文摘Since 2009,ultra-high voltage(UHV)transmission technology has been promoted and applied in China.Over the years,with the accumulation of experience in the construction and operation of UHV projects and the continuous deepening of scientific and technological innovation,UHV technology and key equipment have made great progress.This paper introduces the main achievements of UHV technology innovation from various perspectives including electromagnetic environment,overvoltage and insulation coordination,external insulation and major equipment such as converter transformers,converter valves and gas-insulated transmission lines(GIL).
基金This project is supported by the National Natural Science Foundation of China （Grant No. 71103109）, the National Social Science Foundation of China （No. 09＆ZD029）, the MOE Project of Key Research Institute of Humanities and Social Sciences at Universities in China （No. 2009JJD790029）, and the CAERC Program （Tsinghua/GM/SA1C- China）.
文摘From the view of geographic location, climate and population status, this paper makes a comparative study of the economy structure, transport system, energy supply and carbon emissions among a few cities, especially between Beijing and London, two mega-cities in the world. The developed tertiary industry, consummate transport system and low-carbon energy supply system in London can be referenced to assist Beijing in establishing a low-carbon development pathway. The difference in the statistical coverage of population between these two cities also brings about the divergence of energy consumption per capita and CO2 emissions per capita between them.
