A direct decarbonation route without obvious morphology damage was developed for large micrometer-scale layered double hydroxides（LDHs）.First,we synthesized pure,hexagonal-shaped LDHs with lateral dimension of micro...A direct decarbonation route without obvious morphology damage was developed for large micrometer-scale layered double hydroxides（LDHs）.First,we synthesized pure,hexagonal-shaped LDHs with lateral dimension of micrometer-size by the recently reported urea hydrolysis method.Then,using HNO_3-NaNO_3 mixed solution,the obtained LDH with carbonate anions in the interlayer（LDH_CO_3） was directly decarbonated to its nitrate form,LDH_NO_3,its morphology and particle size were still unchanged.Compared with the recently published two-step decarbonation method,the direct decarbonation reported herein is very convenient.展开更多
Subduction zones,linking the surface and deep carbon reservoirs,significantly affect the Earth’s long-term climate change and habitability.The subducting slabs undergo decarbonation with increasing pressure and tempe...Subduction zones,linking the surface and deep carbon reservoirs,significantly affect the Earth’s long-term climate change and habitability.The subducting slabs undergo decarbonation with increasing pressure and temperature,during which partial carbon mobilizes out of the slab and returns to the surface by arc volcanism or degassing,while the residual carbon continues to descend to greater depths in the mantle.The estimated carbon influx at subduction zones depends strongly on the calculation model,with contributions from sediments ranging from 15 to 60 Mt C/yr,altered ocean basalts from 18 to 61 Mt C/yr,and serpentinized perdotites from 1.3 to 36 Mt C/yr.The carbon influx varies in space and time.Carbon removal from subducting slab occurs through metamorphic reactions,carbonate dissolution,diapirism,hydrocarbon formation and melting.Among these decarbonation mechanisms,diapirism and slab meting play a decisive role in dictating the depth at which surface carbonates can subduct.Specifically,diapirism may restrict sedimentary carbonates at shallow depths(<200 km),while slab melting exhausts all carbonates from the altered ocean crust near transition zones(410–660 km).Consequently,a mechanism enabling surface carbonates to reach the lower mantle,i.e.,ultra-deep carbon cycle,is required to be in accordance with observations by natural samples.展开更多
The accelerated decline of Arctic sea ice since the 1980s has paradoxically amplified greenhouse gas(GHG)emissions through increased shipping activities in this ecologically vulnerable region.This study investigates h...The accelerated decline of Arctic sea ice since the 1980s has paradoxically amplified greenhouse gas(GHG)emissions through increased shipping activities in this ecologically vulnerable region.This study investigates how to reconcile the decarbonization of Arctic shipping with conflicting environmental,economic,and geopolitical interests.Through systematic literature review and interest-balancing analysis,our findings identify three systemic barriers:(1)inadequate adaptation of International Maritime Organization(IMO)regulations to Arctic-specific environmental risks,(2)fragmented enforcement mechanisms among Arctic and non-Arctic States,and(3)technological limitations in clean fuel adoption for ice-class vessels.To address these challenges,a tripartite governance framework is proposed.First,legally binding amendments to International Convention for the Prevention of Pollution from Ships(MARPOL)Annex VI introducing Arctic-specific Energy Efficiency eXisting ship Index(EEXI)standards and extending energy efficiency regulations to fishing vessels.Second,a phased fuel transition prioritizing liquefied natural gas(LNG)and methanol,followed by hydrogen-ammonia synthetics.Third,enhanced multilateral cooperation through an Arctic Climate Shipping Alliance to coordinate joint research and development in cold-adapted technologies and ice-route optimization.By integrating United Nations Convention on the Law of the Sea(UNCLOS)obligations with IMO Polar Code implementation,this study advances a dynamic interest-balancing framework for policymakers,offering actionable pathways to achieve Paris Agreement targets while safeguarding Arctic ecosystems.展开更多
1.Introduction and background Global warming demands low-carbon energy.Ammonia(NH_(3)),a carbon-free hydrogen carrier,offers CO_(2)reduction potential,aligning with decarbonization,per the work of Zhang et al.2.NH_(3)...1.Introduction and background Global warming demands low-carbon energy.Ammonia(NH_(3)),a carbon-free hydrogen carrier,offers CO_(2)reduction potential,aligning with decarbonization,per the work of Zhang et al.2.NH_(3)as a fuel Advantages:NH_(3)offers high hydrogen content ease of storage,cost-effectiveness in large-scale transport,and technological maturity in synthesis.展开更多
AIM:To analyze the environmental impact of patient travel for cataract surgery at a German ophthalmology center.METHODS:All cataract surgeries performed between October 23 and October 27,2023,were analyzed,and all pat...AIM:To analyze the environmental impact of patient travel for cataract surgery at a German ophthalmology center.METHODS:All cataract surgeries performed between October 23 and October 27,2023,were analyzed,and all patient records were reviewed for follow-up visits.All travel distances were calculated,and the associated emissions were quantified.Additionally,patients’utilization of geographically closer branch practices for follow-up care was evaluated,along with the corresponding effects on travel-related emissions.RESULTS:A total of 69 patients underwent unilateral cataract surgery.The average one-way travel distance was 40.1 km(24.9 mi;SD=23.6 km).Corresponding emissions were 1284.8 kg of greenhouse gas(GHG),2.477 kg of nitrogen oxides,and 0.101 kg of particulates.All patients attended at least two follow-up visits.Conducting followup visits at branch practices reduced travel distance by 49.1%.The associated GHG emissions from all travel were 1984.3 kg.Emissions from follow-up visits were 54.4%higher than those from the surgery itself.Total GHG emissions amounted to 3269.1 kg,with an average of 47.4 kg of GHG per patient for all travel associated with cataract surgery.CONCLUSION:A dense network of branch practices contributes to reducing the carbon footprint of cataract surgery-related patient travel;however,the development of digital health approaches for follow-up care is necessary to further optimize the environmental sustainability of cataract surgery.展开更多
With the global economy undergoing decarbonization and a new wave of technological revolution and industrial transformation,supply chain security risks have become increasingly prominent.Major countries are shifting t...With the global economy undergoing decarbonization and a new wave of technological revolution and industrial transformation,supply chain security risks have become increasingly prominent.Major countries are shifting their focus toward critical minerals,beyond traditional common minerals such as iron and copper.The trend is especially notable regarding minerals considered essential for strategically important emerging industries.展开更多
Developing low-carbon and efficient power systems is critical for energy security in the global warming context.We address this issue by focusing on the productivity impact of a decarbonization policy in China’s ther...Developing low-carbon and efficient power systems is critical for energy security in the global warming context.We address this issue by focusing on the productivity impact of a decarbonization policy in China’s thermal power sector—namely,the“Constructing Large Units and Restricting Small Ones”(CLRS)initiative.Utilizing a resource misallocation model,we construct a new theoretical framework to distinguish between technical and allocative efficiency and analyze productivity using plant-level data.The results indicate that the CLRS policy has significantly improved the allocative and technical efficiency of China’s coal-fired power sector,thereby ensuring power security.The closure of outdated and highly distorted small coal-fired units,which have been replaced by technologically advanced large units,primarily drives the enhanced efficiency.The policy’s effects are most pronounced in large-scale power plants and those with high coal combustion efficiency.Furthermore,a comparison of power plants’productivity distribution before and after policy implementation reveals that the CLRS policy not only enhances capital productivity in the coal-fired power sector but also increases rational labor allocation.Our findings have important policy implications for developing countries vis-à-vis building efficient and stable power systems amid climate change.展开更多
World’s First Ammonia-Fueled Vessel Sets Sail The world's first pure ammonia-powered demonstration vessel,the Anhui,successfully completed its maiden voyage in Hefei,east China's Anhui Province,on June 28,mar...World’s First Ammonia-Fueled Vessel Sets Sail The world's first pure ammonia-powered demonstration vessel,the Anhui,successfully completed its maiden voyage in Hefei,east China's Anhui Province,on June 28,marking a major step forward for green shipping.Ammonia,a major chemical industry feedstock,has a high energy density and due to its carbon-free nature,produces only water and nitrogen when fully combusted.This makes it a highly promising fuel for decarbonizing shipping.展开更多
This study investigates the disparities in the deployment of photovoltaic(PV)technology for carbon emissions reduction across different nations,highlighting the mismatch between countries with high economic capacity a...This study investigates the disparities in the deployment of photovoltaic(PV)technology for carbon emissions reduction across different nations,highlighting the mismatch between countries with high economic capacity and those where PV installation would maximize global decarbonization benefits.This mismatch is discussed based on three key factors influencing decarbonization via PV technology:per capita gross domestic product;carbon intensity of the energy system;and solar resource availability.Current PV deployment is predominantly concentrated in economically advanced countries,and does not coincide with regions where the environmental and economic impact of such installations would be most significant.Through a series of thought experiments,it is demonstrated how alternative prioritization strategies could significantly reduce global carbon emissions.Argument is put forward for a globally coordinated approach to PV deployment,particularly targeting high-impact sunbelt regions,to enhance the efficacy of decarbonization efforts and promote equitable energy access.The study underscores the need for international policies that support sustainable energy transitions in economically less developed regions through workforce development and assistance with the activation of capital.展开更多
As decarbonization pressure on traditional fossil fuel-related industries gradually intensifies,CCUS has been increasingly incorporated into energy transition strategies by various oil companies.From a development opp...As decarbonization pressure on traditional fossil fuel-related industries gradually intensifies,CCUS has been increasingly incorporated into energy transition strategies by various oil companies.From a development opportunity perspective,oil companies possess four key advantages in developing the CCUS industry:exploration and development technology advantages;geological resource advantages;capital advantages;source-sink matching advantages.In terms of challenges,oil companies face numerous issues in developing the CCUS industry,including technological development,economic viability,and policy and legal aspects.At the national level,China’s oil companies should advocate for improving and optimizing relevant laws and regulations,enhancing the policy support system,incorporating CCUS into the carbon trading market,and strengthening top-level design and medium-to long-term planning;at the enterprise level,they should continuously advance full industrial chain technologies and reduce CCUS project operating costs,selectively participate in industrial segments that suit their capabilities,strengthen CCUS full industrial chain operational capabilities,and enhance talent development and strengthen international exchange and cooperation.展开更多
In the grand tapestry of the global energy transition,the quest for scalable hydrogen economies emerges as a pivotal thread,weaving together the dual imperatives of decarbonization and industrial pragmatism.Yet,in its...In the grand tapestry of the global energy transition,the quest for scalable hydrogen economies emerges as a pivotal thread,weaving together the dual imperatives of decarbonization and industrial pragmatism.Yet,in its present form,hydrogen production remains deeply entwined with carbon emissions.展开更多
Industrial decarbonization is critical for achieving net-zero goals.The carbon dioxide electrochemical reduction reaction(CO_(2)RR)is a promising approach for converting CO_(2)into high-value chemicals,offering the po...Industrial decarbonization is critical for achieving net-zero goals.The carbon dioxide electrochemical reduction reaction(CO_(2)RR)is a promising approach for converting CO_(2)into high-value chemicals,offering the potential for decarbonizing industrial processes toward a sustainable,carbon-neutral future.However,developing CO_(2)RR catalysts with high selectivity and activity remains a challenge due to the complexity of finding such catalysts and the inefficiency of traditional computational or experimental approaches.Here,we present a methodology integrating density functional theory(DFT)calculations,deep learning models,and an active learning strategy to rapidly screen high-performance catalysts.The proposed methodology is then demonstrated on graphene-based single-atom catalysts for selective CO_(2)electroreduction to methanol.First,we conduct systematic binding energy calculations for 3045 single-atom catalysts to identify thermodynamically stable catalysts as the design space.We then use a graph neural network,fine-tuned with a specialized adsorption energy database,to predict the relative activity and selectivity of the candidate catalysts.An autonomous active learning framework is used to facilitate the exploration of designs.After six learning cycles and 2180 adsorption calculations across 15 intermediates,we develop a surrogate model that identifies four novel catalysts on the Pareto front of activity and selectivity.Our work demonstrates the effectiveness of leveraging a domain foundation model with an active learning framework and holds potential to significantly accelerate the discovery of high-performance CO_(2)RR catalysts.展开更多
This study presents a comparative analysis of electricity, hydrogen, and biodiesel as energy vectors, with a focus on powering an aluminum smelter in southern Italy. It evaluates these vectors in terms of efficiency, ...This study presents a comparative analysis of electricity, hydrogen, and biodiesel as energy vectors, with a focus on powering an aluminum smelter in southern Italy. It evaluates these vectors in terms of efficiency, land requirements for carbon-neutral energy production, and capital expenditure, providing insights throughout the entire supply chain (upstream, midstream, and downstream) into their feasibility for industrial applications. The research reveals that biodiesel, despite being carbon neutral, is impractical due to extensive land requirements and lower efficiency if compared to other vectors. Hydrogen, downstream explored in two forms as thermal power generation and fuel cell technology, shows lower efficiency and higher capital expenditure compared to electricity. Additionally, green hydrogen production’s land requirements significantly exceed those of electricity-based systems. Electricity emerges as the most viable option, offering an overall higher efficiency, lower land requirements for its green production, and comparatively lower capital expenditure. The study’s findings highlight the importance of a holistic assessment of energy vectors, considering economic, environmental, and practical aspects along the entire energy supply chain, especially in industrial applications where the balance of these factors is crucial for long-term sustainability and feasibility. This comprehensive analysis provides valuable guidance for similar industrial applications, emphasizing the need for a balanced approach in the selection of energy vectors.展开更多
Climate change, mainly caused by the use of non-renewable fuels, has raised global concerns and led to the search for less polluting energy sources, making hydrogen a promising energy alternative with the potential to...Climate change, mainly caused by the use of non-renewable fuels, has raised global concerns and led to the search for less polluting energy sources, making hydrogen a promising energy alternative with the potential to contribute to changes in the energy mix of various countries through the use of technologies that enable its production and use with low or zero carbon emissions. In this context, Brazil has aroused great interest from other countries in exploring its renewable resources for the production of hydrogen (green hydrogen). In this sense, the use of natural gas pipelines and the use of hydrogen in mixtures with natural gas have become the subject of studies due to their economically viable alternative for the immediate use of this energy vector. However, there are still technical and regulatory challenges regarding the integration of hydrogen into the existing natural gas pipeline network. In this context, the present study aims to address the effects of hydrogen interaction with the structure of natural gas pipeline steel and the regulatory barriers to the use of this network for the transportation of green hydrogen, particularly in the state of Ceará/Brazil. After extensive analysis of literature and regulatory documents, it was concluded that: 1) Ceará/Brazil has strong potential to meet the demand for green hydrogen through the use of solar and wind energy sources;2) there is feasibility for the adaptation or conversion of natural gas infrastructure for the transportation of green hydrogen;3) discussions regarding the regulatory competence of green hydrogen transportation and distribution through the natural gas network in Brazil are still incipient;4) the current regulation of the natural gas industry can serve as a subsidy for the regulation of green hydrogen and natural gas transportation.展开更多
Decarbonization is often misunderstood in financial studies.Furthermore,its implications for investment opportunities and growth are even less known.The study investigates the link between energy indicators and Tobin&...Decarbonization is often misunderstood in financial studies.Furthermore,its implications for investment opportunities and growth are even less known.The study investigates the link between energy indicators and Tobin's Quotient(TQ)in listed companies globally,finding that the carbon content of energy presents a negative yet modest effect on financial performance.Furthermore,we investigated the effect carbon prices in compliance markets have on TQ for exempted and non-exempt firms,finding that Energy efficiency measures yield greater effects in the latter group.Conversely,it is also true that carbon prices marginally reduce TQ more in non-exempt firms.This implies that auction-mechanisms create burdens that companies are eager to relinquish by reducing emissions.However,reducing GHG yields positive effects on TQ only as long as it results in energy efficiency improvements.展开更多
Aligning with ambitious targets and commitments towards carbon neutrality,countries around the world are desperately seeking an energy transition to cope with the stark reality of the climate crisis and the surge in d...Aligning with ambitious targets and commitments towards carbon neutrality,countries around the world are desperately seeking an energy transition to cope with the stark reality of the climate crisis and the surge in demand for heating and cooling.Increased penetration of renewable power is foreshadowing a shift in global energy dominance,from fossil fuel based heating to renewable power based heating.However,we have to address four underlying challenges in energy transition,including(1)to achieve heat electrification,(2)to utilize decommissioned thermal power plants,(3)to meet the demand for large-scale heat storage,and(4)to puzzle out thefinal“10%”emissions.Given the above challenges,we put forth four heat pump-assisted approaches to break the bottleneck of energy transition and facilitate effective incentive strategies for policymakers.We highlight that the efficiency andflexibility of heat pumps in thermal energy regulation enable them to push forward an immense influence on the future energy transition for the heating/cooling supply that accounts for 50%of the energy consumption for users and the last“10%”carbon emissions.展开更多
A crystalline sapphire （Al2O3） boule （Ф10 × 80mm^3） grown by the temperature gradient technique （TGT） is a bit colored due to carbon volatilization from the graphite heater at high temperatures and the abs...A crystalline sapphire （Al2O3） boule （Ф10 × 80mm^3） grown by the temperature gradient technique （TGT） is a bit colored due to carbon volatilization from the graphite heater at high temperatures and the absorption of transitional metal inclusions in the raw material. The sapphire becomes colorless and transparent after decolorization and decarbonization in successive annealings in air and hydrogen at high temperatures. The quality, optical transmissivity,and homogeneity of the sapphire are remarkably improved.展开更多
In this paper, the properties of S25C-SUS405 steel joints by vacuum diffusion welding are discussed, and the specific deformation, tensile strength and hardness of the joints made of those two kinds of steel are intro...In this paper, the properties of S25C-SUS405 steel joints by vacuum diffusion welding are discussed, and the specific deformation, tensile strength and hardness of the joints made of those two kinds of steel are introduced. Through metallographic examination and microanalysis, it can be observed that at the weld interface of the joints there is a decarbonized layer on the S25C steel side and a carburized layer on the SUS405 steel side. This is the main cause giving rise to the heterogeneity of microstructure distribution and the nonuniformity of hardness distribution in weldment. In addition, with the help of electronic probe microanalysis the element distribution, such as carbon and chrome, is reported in this paper.展开更多
On the basis of understanding the principle of rotary triboelectrostatic separation, dynamic analysis of charged fly ash particles aimed at determining the key factors and separation experiments to improve decarboniza...On the basis of understanding the principle of rotary triboelectrostatic separation, dynamic analysis of charged fly ash particles aimed at determining the key factors and separation experiments to improve decarbonization efficiency had been carried out Variables of electrode plate voltage and corrected wind speed are the key factors which affect the decarbonization efficiency on the separation of fly ash, The results of separation experiments show that:(1) With the plate voltage increasing, the efficiency of decarbonization continuously rises and in its selected range, the optimal voltage level is 45 KV;(2) The corrected wind speed can impact the efficiency of decarbonization significantly: with the speed increasing, the efficiency of decarbonization shows a trend of first decline, then increase and decrease again, and in its selected range, the optimal speed is 2.0 m/s. This study is of significance for the improvement of rotary triboelectrostatic separation performance and its decarbonization separation efficiency.展开更多
The basic principle of fly ash triboelectrification is analysed. The mineral electrical index and test method are introduced. The electric difference of different mineral composition of fly ash is discussed by analysi...The basic principle of fly ash triboelectrification is analysed. The mineral electrical index and test method are introduced. The electric difference of different mineral composition of fly ash is discussed by analysis of chemical and mineral composition of fly ash in Xinwen power plant. The dielectric constant and charge-mass ratio of carbon and ash of fly ash are tested. Combined with the experimental study on rotary triboelectrostatic separation, the charged characteristic of fly ash particles with different size is gained. The results show that the dielectric constant of fly ash with different grain size decreased with the decrease of particle size, which lead to the poor electrical conductivity, Thus it can be seen that par- ticle size plays a leading role in conductivity, The charge of carbon and ash with each size increased with the decreased of particle size; and the charge-mass ratio between carbon and ash with the same size lar- ger with the decrease of size, which indicated that the finer particle size, the more favorable for triboelec- trification separation. In the same conditions, the best decarburization effect is realized when the particle size ranges from 0.038 to 0.074 ram, whose decarbonization rate and efficiency index reached 38.93% and 120.83% respectively.展开更多
基金the National Natural Science Foundation of China(No.5 1073 162)for financial supportK.C. Wong Education Foundation,Hong Kong
文摘A direct decarbonation route without obvious morphology damage was developed for large micrometer-scale layered double hydroxides（LDHs）.First,we synthesized pure,hexagonal-shaped LDHs with lateral dimension of micrometer-size by the recently reported urea hydrolysis method.Then,using HNO_3-NaNO_3 mixed solution,the obtained LDH with carbonate anions in the interlayer（LDH_CO_3） was directly decarbonated to its nitrate form,LDH_NO_3,its morphology and particle size were still unchanged.Compared with the recently published two-step decarbonation method,the direct decarbonation reported herein is very convenient.
基金supported by the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2022QNLM050201-3)the National Key R&D Program of China(No.2022YFF0801000)the National Natural Science Foundation of China(Nos.92158206,42003049).
文摘Subduction zones,linking the surface and deep carbon reservoirs,significantly affect the Earth’s long-term climate change and habitability.The subducting slabs undergo decarbonation with increasing pressure and temperature,during which partial carbon mobilizes out of the slab and returns to the surface by arc volcanism or degassing,while the residual carbon continues to descend to greater depths in the mantle.The estimated carbon influx at subduction zones depends strongly on the calculation model,with contributions from sediments ranging from 15 to 60 Mt C/yr,altered ocean basalts from 18 to 61 Mt C/yr,and serpentinized perdotites from 1.3 to 36 Mt C/yr.The carbon influx varies in space and time.Carbon removal from subducting slab occurs through metamorphic reactions,carbonate dissolution,diapirism,hydrocarbon formation and melting.Among these decarbonation mechanisms,diapirism and slab meting play a decisive role in dictating the depth at which surface carbonates can subduct.Specifically,diapirism may restrict sedimentary carbonates at shallow depths(<200 km),while slab melting exhausts all carbonates from the altered ocean crust near transition zones(410–660 km).Consequently,a mechanism enabling surface carbonates to reach the lower mantle,i.e.,ultra-deep carbon cycle,is required to be in accordance with observations by natural samples.
基金supported by the Major Research Projects of the National Social Science Fund of China(NSFC,Grant no.23VHQ015).
文摘The accelerated decline of Arctic sea ice since the 1980s has paradoxically amplified greenhouse gas(GHG)emissions through increased shipping activities in this ecologically vulnerable region.This study investigates how to reconcile the decarbonization of Arctic shipping with conflicting environmental,economic,and geopolitical interests.Through systematic literature review and interest-balancing analysis,our findings identify three systemic barriers:(1)inadequate adaptation of International Maritime Organization(IMO)regulations to Arctic-specific environmental risks,(2)fragmented enforcement mechanisms among Arctic and non-Arctic States,and(3)technological limitations in clean fuel adoption for ice-class vessels.To address these challenges,a tripartite governance framework is proposed.First,legally binding amendments to International Convention for the Prevention of Pollution from Ships(MARPOL)Annex VI introducing Arctic-specific Energy Efficiency eXisting ship Index(EEXI)standards and extending energy efficiency regulations to fishing vessels.Second,a phased fuel transition prioritizing liquefied natural gas(LNG)and methanol,followed by hydrogen-ammonia synthetics.Third,enhanced multilateral cooperation through an Arctic Climate Shipping Alliance to coordinate joint research and development in cold-adapted technologies and ice-route optimization.By integrating United Nations Convention on the Law of the Sea(UNCLOS)obligations with IMO Polar Code implementation,this study advances a dynamic interest-balancing framework for policymakers,offering actionable pathways to achieve Paris Agreement targets while safeguarding Arctic ecosystems.
文摘1.Introduction and background Global warming demands low-carbon energy.Ammonia(NH_(3)),a carbon-free hydrogen carrier,offers CO_(2)reduction potential,aligning with decarbonization,per the work of Zhang et al.2.NH_(3)as a fuel Advantages:NH_(3)offers high hydrogen content ease of storage,cost-effectiveness in large-scale transport,and technological maturity in synthesis.
文摘AIM:To analyze the environmental impact of patient travel for cataract surgery at a German ophthalmology center.METHODS:All cataract surgeries performed between October 23 and October 27,2023,were analyzed,and all patient records were reviewed for follow-up visits.All travel distances were calculated,and the associated emissions were quantified.Additionally,patients’utilization of geographically closer branch practices for follow-up care was evaluated,along with the corresponding effects on travel-related emissions.RESULTS:A total of 69 patients underwent unilateral cataract surgery.The average one-way travel distance was 40.1 km(24.9 mi;SD=23.6 km).Corresponding emissions were 1284.8 kg of greenhouse gas(GHG),2.477 kg of nitrogen oxides,and 0.101 kg of particulates.All patients attended at least two follow-up visits.Conducting followup visits at branch practices reduced travel distance by 49.1%.The associated GHG emissions from all travel were 1984.3 kg.Emissions from follow-up visits were 54.4%higher than those from the surgery itself.Total GHG emissions amounted to 3269.1 kg,with an average of 47.4 kg of GHG per patient for all travel associated with cataract surgery.CONCLUSION:A dense network of branch practices contributes to reducing the carbon footprint of cataract surgery-related patient travel;however,the development of digital health approaches for follow-up care is necessary to further optimize the environmental sustainability of cataract surgery.
文摘With the global economy undergoing decarbonization and a new wave of technological revolution and industrial transformation,supply chain security risks have become increasingly prominent.Major countries are shifting their focus toward critical minerals,beyond traditional common minerals such as iron and copper.The trend is especially notable regarding minerals considered essential for strategically important emerging industries.
基金supported by the Chengdu Philosophy and Social Science Planning Project[Grant No.2022C05]National Natural Science Foundation of China[Grant No.71904158].
文摘Developing low-carbon and efficient power systems is critical for energy security in the global warming context.We address this issue by focusing on the productivity impact of a decarbonization policy in China’s thermal power sector—namely,the“Constructing Large Units and Restricting Small Ones”(CLRS)initiative.Utilizing a resource misallocation model,we construct a new theoretical framework to distinguish between technical and allocative efficiency and analyze productivity using plant-level data.The results indicate that the CLRS policy has significantly improved the allocative and technical efficiency of China’s coal-fired power sector,thereby ensuring power security.The closure of outdated and highly distorted small coal-fired units,which have been replaced by technologically advanced large units,primarily drives the enhanced efficiency.The policy’s effects are most pronounced in large-scale power plants and those with high coal combustion efficiency.Furthermore,a comparison of power plants’productivity distribution before and after policy implementation reveals that the CLRS policy not only enhances capital productivity in the coal-fired power sector but also increases rational labor allocation.Our findings have important policy implications for developing countries vis-à-vis building efficient and stable power systems amid climate change.
文摘World’s First Ammonia-Fueled Vessel Sets Sail The world's first pure ammonia-powered demonstration vessel,the Anhui,successfully completed its maiden voyage in Hefei,east China's Anhui Province,on June 28,marking a major step forward for green shipping.Ammonia,a major chemical industry feedstock,has a high energy density and due to its carbon-free nature,produces only water and nitrogen when fully combusted.This makes it a highly promising fuel for decarbonizing shipping.
基金supported by the Helmholtz Association within the framework of the innovation platform“Solar TAP”[Az:714-62150-3/1(2023)]co-funded by the European Union(ERC,C2C-PV,project number 101088359)。
文摘This study investigates the disparities in the deployment of photovoltaic(PV)technology for carbon emissions reduction across different nations,highlighting the mismatch between countries with high economic capacity and those where PV installation would maximize global decarbonization benefits.This mismatch is discussed based on three key factors influencing decarbonization via PV technology:per capita gross domestic product;carbon intensity of the energy system;and solar resource availability.Current PV deployment is predominantly concentrated in economically advanced countries,and does not coincide with regions where the environmental and economic impact of such installations would be most significant.Through a series of thought experiments,it is demonstrated how alternative prioritization strategies could significantly reduce global carbon emissions.Argument is put forward for a globally coordinated approach to PV deployment,particularly targeting high-impact sunbelt regions,to enhance the efficacy of decarbonization efforts and promote equitable energy access.The study underscores the need for international policies that support sustainable energy transitions in economically less developed regions through workforce development and assistance with the activation of capital.
文摘As decarbonization pressure on traditional fossil fuel-related industries gradually intensifies,CCUS has been increasingly incorporated into energy transition strategies by various oil companies.From a development opportunity perspective,oil companies possess four key advantages in developing the CCUS industry:exploration and development technology advantages;geological resource advantages;capital advantages;source-sink matching advantages.In terms of challenges,oil companies face numerous issues in developing the CCUS industry,including technological development,economic viability,and policy and legal aspects.At the national level,China’s oil companies should advocate for improving and optimizing relevant laws and regulations,enhancing the policy support system,incorporating CCUS into the carbon trading market,and strengthening top-level design and medium-to long-term planning;at the enterprise level,they should continuously advance full industrial chain technologies and reduce CCUS project operating costs,selectively participate in industrial segments that suit their capabilities,strengthen CCUS full industrial chain operational capabilities,and enhance talent development and strengthen international exchange and cooperation.
基金financially supported by the National Natural Science Foundation of China(22225902)the National Key Research&Development Program of China(2022YFE0115900)。
文摘In the grand tapestry of the global energy transition,the quest for scalable hydrogen economies emerges as a pivotal thread,weaving together the dual imperatives of decarbonization and industrial pragmatism.Yet,in its present form,hydrogen production remains deeply entwined with carbon emissions.
基金supported by the National Key Research and Development Program of China(2022ZD0117501)the Scientific Research Innovation Capability Support Project for Young Faculty(ZYGXQNJSKYCXNLZCXM-E7)the Tsinghua University Initiative Scientific Research Program and the Carbon Neutrality and Energy System Transformation(CNEST)Program led by Tsinghua University.
文摘Industrial decarbonization is critical for achieving net-zero goals.The carbon dioxide electrochemical reduction reaction(CO_(2)RR)is a promising approach for converting CO_(2)into high-value chemicals,offering the potential for decarbonizing industrial processes toward a sustainable,carbon-neutral future.However,developing CO_(2)RR catalysts with high selectivity and activity remains a challenge due to the complexity of finding such catalysts and the inefficiency of traditional computational or experimental approaches.Here,we present a methodology integrating density functional theory(DFT)calculations,deep learning models,and an active learning strategy to rapidly screen high-performance catalysts.The proposed methodology is then demonstrated on graphene-based single-atom catalysts for selective CO_(2)electroreduction to methanol.First,we conduct systematic binding energy calculations for 3045 single-atom catalysts to identify thermodynamically stable catalysts as the design space.We then use a graph neural network,fine-tuned with a specialized adsorption energy database,to predict the relative activity and selectivity of the candidate catalysts.An autonomous active learning framework is used to facilitate the exploration of designs.After six learning cycles and 2180 adsorption calculations across 15 intermediates,we develop a surrogate model that identifies four novel catalysts on the Pareto front of activity and selectivity.Our work demonstrates the effectiveness of leveraging a domain foundation model with an active learning framework and holds potential to significantly accelerate the discovery of high-performance CO_(2)RR catalysts.
文摘This study presents a comparative analysis of electricity, hydrogen, and biodiesel as energy vectors, with a focus on powering an aluminum smelter in southern Italy. It evaluates these vectors in terms of efficiency, land requirements for carbon-neutral energy production, and capital expenditure, providing insights throughout the entire supply chain (upstream, midstream, and downstream) into their feasibility for industrial applications. The research reveals that biodiesel, despite being carbon neutral, is impractical due to extensive land requirements and lower efficiency if compared to other vectors. Hydrogen, downstream explored in two forms as thermal power generation and fuel cell technology, shows lower efficiency and higher capital expenditure compared to electricity. Additionally, green hydrogen production’s land requirements significantly exceed those of electricity-based systems. Electricity emerges as the most viable option, offering an overall higher efficiency, lower land requirements for its green production, and comparatively lower capital expenditure. The study’s findings highlight the importance of a holistic assessment of energy vectors, considering economic, environmental, and practical aspects along the entire energy supply chain, especially in industrial applications where the balance of these factors is crucial for long-term sustainability and feasibility. This comprehensive analysis provides valuable guidance for similar industrial applications, emphasizing the need for a balanced approach in the selection of energy vectors.
文摘Climate change, mainly caused by the use of non-renewable fuels, has raised global concerns and led to the search for less polluting energy sources, making hydrogen a promising energy alternative with the potential to contribute to changes in the energy mix of various countries through the use of technologies that enable its production and use with low or zero carbon emissions. In this context, Brazil has aroused great interest from other countries in exploring its renewable resources for the production of hydrogen (green hydrogen). In this sense, the use of natural gas pipelines and the use of hydrogen in mixtures with natural gas have become the subject of studies due to their economically viable alternative for the immediate use of this energy vector. However, there are still technical and regulatory challenges regarding the integration of hydrogen into the existing natural gas pipeline network. In this context, the present study aims to address the effects of hydrogen interaction with the structure of natural gas pipeline steel and the regulatory barriers to the use of this network for the transportation of green hydrogen, particularly in the state of Ceará/Brazil. After extensive analysis of literature and regulatory documents, it was concluded that: 1) Ceará/Brazil has strong potential to meet the demand for green hydrogen through the use of solar and wind energy sources;2) there is feasibility for the adaptation or conversion of natural gas infrastructure for the transportation of green hydrogen;3) discussions regarding the regulatory competence of green hydrogen transportation and distribution through the natural gas network in Brazil are still incipient;4) the current regulation of the natural gas industry can serve as a subsidy for the regulation of green hydrogen and natural gas transportation.
文摘Decarbonization is often misunderstood in financial studies.Furthermore,its implications for investment opportunities and growth are even less known.The study investigates the link between energy indicators and Tobin's Quotient(TQ)in listed companies globally,finding that the carbon content of energy presents a negative yet modest effect on financial performance.Furthermore,we investigated the effect carbon prices in compliance markets have on TQ for exempted and non-exempt firms,finding that Energy efficiency measures yield greater effects in the latter group.Conversely,it is also true that carbon prices marginally reduce TQ more in non-exempt firms.This implies that auction-mechanisms create burdens that companies are eager to relinquish by reducing emissions.However,reducing GHG yields positive effects on TQ only as long as it results in energy efficiency improvements.
基金funded by the National Natural Science Foundation of China(No.52036004,52293411)Shanghai International collaborative research program(No.22160711300)supported by“the Fundamental Research Funds for the Central Universities”.
文摘Aligning with ambitious targets and commitments towards carbon neutrality,countries around the world are desperately seeking an energy transition to cope with the stark reality of the climate crisis and the surge in demand for heating and cooling.Increased penetration of renewable power is foreshadowing a shift in global energy dominance,from fossil fuel based heating to renewable power based heating.However,we have to address four underlying challenges in energy transition,including(1)to achieve heat electrification,(2)to utilize decommissioned thermal power plants,(3)to meet the demand for large-scale heat storage,and(4)to puzzle out thefinal“10%”emissions.Given the above challenges,we put forth four heat pump-assisted approaches to break the bottleneck of energy transition and facilitate effective incentive strategies for policymakers.We highlight that the efficiency andflexibility of heat pumps in thermal energy regulation enable them to push forward an immense influence on the future energy transition for the heating/cooling supply that accounts for 50%of the energy consumption for users and the last“10%”carbon emissions.
文摘A crystalline sapphire （Al2O3） boule （Ф10 × 80mm^3） grown by the temperature gradient technique （TGT） is a bit colored due to carbon volatilization from the graphite heater at high temperatures and the absorption of transitional metal inclusions in the raw material. The sapphire becomes colorless and transparent after decolorization and decarbonization in successive annealings in air and hydrogen at high temperatures. The quality, optical transmissivity,and homogeneity of the sapphire are remarkably improved.
文摘In this paper, the properties of S25C-SUS405 steel joints by vacuum diffusion welding are discussed, and the specific deformation, tensile strength and hardness of the joints made of those two kinds of steel are introduced. Through metallographic examination and microanalysis, it can be observed that at the weld interface of the joints there is a decarbonized layer on the S25C steel side and a carburized layer on the SUS405 steel side. This is the main cause giving rise to the heterogeneity of microstructure distribution and the nonuniformity of hardness distribution in weldment. In addition, with the help of electronic probe microanalysis the element distribution, such as carbon and chrome, is reported in this paper.
基金provided by the National Natural Science Foundation of China(No.51274200)Research Fund for the Doctoral Program of Higher Education of China(No.20130095110010)
文摘On the basis of understanding the principle of rotary triboelectrostatic separation, dynamic analysis of charged fly ash particles aimed at determining the key factors and separation experiments to improve decarbonization efficiency had been carried out Variables of electrode plate voltage and corrected wind speed are the key factors which affect the decarbonization efficiency on the separation of fly ash, The results of separation experiments show that:(1) With the plate voltage increasing, the efficiency of decarbonization continuously rises and in its selected range, the optimal voltage level is 45 KV;(2) The corrected wind speed can impact the efficiency of decarbonization significantly: with the speed increasing, the efficiency of decarbonization shows a trend of first decline, then increase and decrease again, and in its selected range, the optimal speed is 2.0 m/s. This study is of significance for the improvement of rotary triboelectrostatic separation performance and its decarbonization separation efficiency.
基金supported by the National Natural Science Foundation of China(Nos.51274200 and 51221462)
文摘The basic principle of fly ash triboelectrification is analysed. The mineral electrical index and test method are introduced. The electric difference of different mineral composition of fly ash is discussed by analysis of chemical and mineral composition of fly ash in Xinwen power plant. The dielectric constant and charge-mass ratio of carbon and ash of fly ash are tested. Combined with the experimental study on rotary triboelectrostatic separation, the charged characteristic of fly ash particles with different size is gained. The results show that the dielectric constant of fly ash with different grain size decreased with the decrease of particle size, which lead to the poor electrical conductivity, Thus it can be seen that par- ticle size plays a leading role in conductivity, The charge of carbon and ash with each size increased with the decreased of particle size; and the charge-mass ratio between carbon and ash with the same size lar- ger with the decrease of size, which indicated that the finer particle size, the more favorable for triboelec- trification separation. In the same conditions, the best decarburization effect is realized when the particle size ranges from 0.038 to 0.074 ram, whose decarbonization rate and efficiency index reached 38.93% and 120.83% respectively.
