Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulc...Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.展开更多
Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol...Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol/L)activated tricalcium phosphate(TO-0.1)provided the most efficient stabilization of Cd and Zn.After 30 d treatment,leaching concentrations of Cd and Zn in soil were decreased from 3.17 and 16.60 mg/L to 0.078 and 0.32 mg/L,respectively.The acid-soluble fractions of Cd and Zn were transformed into reducible,oxidizable,and residual fractions.Notably,As mobility in TO-0.1 treated soils did not increase.In addition,acid rain leaching and 150 d of natural aging revealed that the slow-release phosphate material provided long-term stability for the stabilization of Cd and Zn.This study verifies the potential application of slow-release phosphate materials for the remediation of heavy metal contaminated soil at smelting sites.展开更多
Using phosphorus(P)fertilizers has historically increased agricultural productivity,yet the highly dissipative nature of phosphate rock and the low effciency due to soil fxation and runoff raise sustainability concern...Using phosphorus(P)fertilizers has historically increased agricultural productivity,yet the highly dissipative nature of phosphate rock and the low effciency due to soil fxation and runoff raise sustainability concerns.Algae fertilizers have emerged as a promising eco-friendly alternative.However,the potential of algae fertilizers for providing sustained P availability and their impacts on plant growth,soil microbes,and nutrient cycling remains to be explored.In this study,we developed a polyphosphate-enriched algae fertilizer(PEA)and conducted comparative experiments with chemical P fertilizers(CP)through soil and solution cultures,as well as crop growth trials.Soil cultivation experiments showed that PEA released twice as much labile P as initially available in the soil,and it functioned as a slow-release P source.In contrast,soils treated with CP initially exhibited high levels of labile P,which was gradually converted to stable forms,but it dropped to 30%of the labile P level in PEA after three months.Further tests revealed that the slow release of P from PEA was linked to increased microbial activity,and the microbial biomass P(MBP)content was about eight times higher than in soils treated with CP after three months,resulting in a 75%decline in the microbial biomass carbon(MBC)to MBP ratio.Microbial diversity analysis showed that algae fertilizers could recruit more benefcial microbes than CP,like phosphorus-solubilizing bacteria,plant growth-promoting bacteria,and stress-resistant bacteria.Crop pot experiments,along with amplicon and metagenomic analysis of tomato root-associated microbes,revealed that algae fertilizers including PEA promoted plant growth comparable to CP,and enhanced soil P cycling and overall nutrient dynamics.These data showed that algae fertilizers,especially PEA,can stabilize soil P fertility and stimulate plant growth through their slow P release and the recruitment of benefcial microbes.Our study highlights the potential of PEA to foster sustainable agriculture by mitigating the P scarcity and soil P loss associated with chemical fertilizers and improving plant growth and soil health.展开更多
AI Agent技术凭借环境感知、自主决策与协同执行能力,为财务共享服务中心的智能化升级提供了新型技术方案。财务共享中心作为集约化财务管理载体,在业务规模扩张与数据量激增的背景下,面临着风险识别滞后与资金结算效率不足等挑战,AI Ag...AI Agent技术凭借环境感知、自主决策与协同执行能力,为财务共享服务中心的智能化升级提供了新型技术方案。财务共享中心作为集约化财务管理载体,在业务规模扩张与数据量激增的背景下,面临着风险识别滞后与资金结算效率不足等挑战,AI Agent通过构建智能识别预警系统、动态评估管控体系、自动化应急处置机制及全程追踪管理框架,实现了交易异常、信用风险、资金异常与合规风险的精准防控。展开更多
Artificial intelligence(AI)is reshaping financial systems and services,as intelligent AI agents increasingly form the foundation of autonomous,goal-driven systems capable of reasoning,learning,and action.This review s...Artificial intelligence(AI)is reshaping financial systems and services,as intelligent AI agents increasingly form the foundation of autonomous,goal-driven systems capable of reasoning,learning,and action.This review synthesizes recent research and developments in the application of AI agents across core financial domains.Specifically,it covers the deployment of agent-based AI in algorithmic trading,fraud detection,credit risk assessment,roboadvisory,and regulatory compliance(RegTech).The review focuses on advanced agent-based methodologies,including reinforcement learning,multi-agent systems,and autonomous decision-making frameworks,particularly those leveraging large language models(LLMs),contrasting these with traditional AI or purely statistical models.Our primary goals are to consolidate current knowledge,identify significant trends and architectural approaches,review the practical efficiency and impact of current applications,and delineate key challenges and promising future research directions.The increasing sophistication of AI agents offers unprecedented opportunities for innovation in finance,yet presents complex technical,ethical,and regulatory challenges that demand careful consideration and proactive strategies.This review aims to provide a comprehensive understanding of this rapidly evolving landscape,highlighting the role of agent-based AI in the ongoing transformation of the financial industry,and is intended to serve financial institutions,regulators,investors,analysts,researchers,and other key stakeholders in the financial ecosystem.展开更多
The chemical structure of polyamide 6(PA6)dictates that only 50%of hydrogen bonds participate in crystallization during the crystallization process,resulting in the properties of its products being significantly depen...The chemical structure of polyamide 6(PA6)dictates that only 50%of hydrogen bonds participate in crystallization during the crystallization process,resulting in the properties of its products being significantly dependent on the molding process.Therefore,the design and development of nucleating agents suitable for PA6 holds great practical significance for high-performance PA6 materials.Amide-based nucleating agents can effectively improve the crystallization rate by increasing intermolecular hydrogen bond density.Further introduction of hydroxyl groups can enhance the hydrogen bonding interactions between the nucleating agent and PA6.In this study,a hydroxyl-containing amidebased nucleating agent,BHT,was designed and synthesized using a tyramine-based biomass as the raw material.These results demonstrated that BHT exhibited good structural compatibility with PA6.After adding 1 wt%BHT,the crystallization temperature of PA6 increased from 170.9℃to 193.3℃,the crystallinity increased 16.6%,the heat distortion temperature and Vicat softening temperature rose to 89.5 and 187.8℃,respectively,the haze decreased to 46%,achieving the synergistic optimization of mechanical,thermal,and optical properties.The in situ time-resolved FTIR results indicated that the addition of BHT increased the enthalpy of hydrogen bond formation during the nucleation stage,facilitated the segmental conformation adjustment of PA6,and enhanced the molar concentration of trans-conformations,ultimately leading to an improvement in the crystallization rate.展开更多
The crystallization and aggregation characteristics of the active layer components in organic solar cells(OSCs)are one of the core factors determining photovoltaic performance,influencing the entire process from light...The crystallization and aggregation characteristics of the active layer components in organic solar cells(OSCs)are one of the core factors determining photovoltaic performance,influencing the entire process from light absorption to charge separation,transport,and ultimately charge collection.Dynamic changes in crystallization and aggregation states can also disrupt the microstructure of the active layer,thus shortening the lifetime of the cell.In this study,a morphology modulation strategy is proposed to regulate the crystallization kinetics of non-fullerene acceptors by employing the polymer molecule PYIT as a nucleating agent.An appropriate amount of PYIT was first completely dissolved with the non-fullerene acceptor Y6 and left to stand for 24 h,followed by the fabrication of layer-by-layer processed OSCs.Experiments demonstrated that high crystallinity of PYIT allows it to act as a crystallization nucleus,promoting the crystallization,orientation consistency,and ordered stacking of the acceptor.These nanoscale structural optimizations facilitate efficient charge transport,enhance exciton dissociation efficiency,and suppress unfavorable energetic disorder.Consequently,not only was the power conversion efficiency(PCE)of D18-Cl/Y6-based layer-by-layer processed OSC increased from 18.08%to 19.13%,but the atmospheric stability and long-term lifetime of the OSCs were also significantly improved.Notably,this strategy is also applicable to indoor OSCs,and the PYIT-optimized device can achieve a PCE of 27.0%under 1000 lux light-emitting diode(LED,3200K)irradiation,which is superior to that of the control device(24.2%).This work develops a crystal engineering strategy that is able to simultaneously optimize the microscopic morphology and charge dynamics properties in OSCs,thereby achieving simultaneous improvement in efficiency and stability.展开更多
With the rise of AI-assisted education,many instructors and engineers seek to deliver high-quality programming courses online.However,crafting effective programming lectures remains a challenge,particularly for instru...With the rise of AI-assisted education,many instructors and engineers seek to deliver high-quality programming courses online.However,crafting effective programming lectures remains a challenge,particularly for instructors lacking pedagogical training or multilingual fluency.We present CourseAgent,a prompt-driven framework that leverages large language models(LLMs)to automatically generate Python tutorials,structured lecture scripts,and accompanying audio narrations.CourseAgent accepts raw code as input and transforms it into segmented,well-commented code blocks,adapting content to different difficulty levels and languages via prompt customization.Our system supports multilingual instruction(e.g.,Chinese,English),fine-grained control of pedagogical depth,and auto-generation of lecture videos.We evaluate the output generated by CourseAgent using real student feedback and feedback from in-service teachers,alongside automated assessments from LLMs.These evaluations demonstrate that the materials produced by CourseAgent are coherent,pedagogically sound,and comparable in quality to those created by experienced instructors.CourseAgent lowers the barrier to quality programming education and shows promise for scalable,personalized,and language-adaptive content generation.展开更多
Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may po...Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management.展开更多
Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl m...Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl methylphosphonate(DIMP),a commonly used CWA surrogate,is widely studied to enhance our understanding of CWA behavior.The prevailing thermal decomposition model for DIMP,developed approximately 25 years ago,is based on data collected in nitrogen atmospheres at temperatures ranging from 700 K to 800 K.Despite its limitations,this model continues to serve as a foundation for research across various thermal and reactive environments,including combustion studies.Our recent experiments have extended the scope of decomposition analysis by examining DIMP in both nitrogen and zero air across a lower temperature range of 175℃ to 250℃.Infrared spectroscopy results under nitrogen align well with the established model;however,we observed that catalytic effects,stemming from decomposition byproducts and interactions with stainless steel surfaces,alter the reaction kinetics.In zero air environments,we observed a novel infrared absorption band.Spectral fitting suggests this band may represent a combination of propanal and acetone,while GCMS analysis points to vinyl formate and acetone as possible constituents.Although the precise identity of these new products remains unresolved,our findings clearly indicate that the existing decomposition model cannot be reliably extended to lower temperatures or non-nitrogen environments without further revisions.展开更多
基金supported by the National Natural Science Foundation of China(No.32071980)the Key Projects of Shaanxi Agricultural Collaborative Innovation and Extension Alliance(No.LMZD202201)+1 种基金the Key R&D Project in Shaanxi Province(No.2021LLRH-07)Shaanxi Natural Scientific Basic Research Program project(No.2022JQ-157).
文摘Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.
基金supported by the Natural Science Foundation of Hunan Province,China(No.2024JJ1012)the Postgraduate Innovative Project of Central South University,China(No.2023ZZTS0459)the National Key Research and Development Program of China(No.2019YFC1803605)。
文摘Slow-release phosphate materials were prepared by activating insoluble phosphate with organic acid to stabilize high concentrations of Cd and Zn in contaminated smelter soil.The results showed that oxalic acid(0.1 mol/L)activated tricalcium phosphate(TO-0.1)provided the most efficient stabilization of Cd and Zn.After 30 d treatment,leaching concentrations of Cd and Zn in soil were decreased from 3.17 and 16.60 mg/L to 0.078 and 0.32 mg/L,respectively.The acid-soluble fractions of Cd and Zn were transformed into reducible,oxidizable,and residual fractions.Notably,As mobility in TO-0.1 treated soils did not increase.In addition,acid rain leaching and 150 d of natural aging revealed that the slow-release phosphate material provided long-term stability for the stabilization of Cd and Zn.This study verifies the potential application of slow-release phosphate materials for the remediation of heavy metal contaminated soil at smelting sites.
基金supported by the National Key Research and Development Program of China(2021YFF1000404)the National Natural Science Foundation of China(32472823 and 32102478)+1 种基金the Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-CSAL-202301)the China Postdoctoral Science Foundation(2021M693447,2021M693449 and 2022T150707)。
文摘Using phosphorus(P)fertilizers has historically increased agricultural productivity,yet the highly dissipative nature of phosphate rock and the low effciency due to soil fxation and runoff raise sustainability concerns.Algae fertilizers have emerged as a promising eco-friendly alternative.However,the potential of algae fertilizers for providing sustained P availability and their impacts on plant growth,soil microbes,and nutrient cycling remains to be explored.In this study,we developed a polyphosphate-enriched algae fertilizer(PEA)and conducted comparative experiments with chemical P fertilizers(CP)through soil and solution cultures,as well as crop growth trials.Soil cultivation experiments showed that PEA released twice as much labile P as initially available in the soil,and it functioned as a slow-release P source.In contrast,soils treated with CP initially exhibited high levels of labile P,which was gradually converted to stable forms,but it dropped to 30%of the labile P level in PEA after three months.Further tests revealed that the slow release of P from PEA was linked to increased microbial activity,and the microbial biomass P(MBP)content was about eight times higher than in soils treated with CP after three months,resulting in a 75%decline in the microbial biomass carbon(MBC)to MBP ratio.Microbial diversity analysis showed that algae fertilizers could recruit more benefcial microbes than CP,like phosphorus-solubilizing bacteria,plant growth-promoting bacteria,and stress-resistant bacteria.Crop pot experiments,along with amplicon and metagenomic analysis of tomato root-associated microbes,revealed that algae fertilizers including PEA promoted plant growth comparable to CP,and enhanced soil P cycling and overall nutrient dynamics.These data showed that algae fertilizers,especially PEA,can stabilize soil P fertility and stimulate plant growth through their slow P release and the recruitment of benefcial microbes.Our study highlights the potential of PEA to foster sustainable agriculture by mitigating the P scarcity and soil P loss associated with chemical fertilizers and improving plant growth and soil health.
基金supported by the Ministry of Education and Science of the Republic of North Macedonia through the project“Utilizing AI and National Large Language Models to Advance Macedonian Language Capabilties”。
文摘Artificial intelligence(AI)is reshaping financial systems and services,as intelligent AI agents increasingly form the foundation of autonomous,goal-driven systems capable of reasoning,learning,and action.This review synthesizes recent research and developments in the application of AI agents across core financial domains.Specifically,it covers the deployment of agent-based AI in algorithmic trading,fraud detection,credit risk assessment,roboadvisory,and regulatory compliance(RegTech).The review focuses on advanced agent-based methodologies,including reinforcement learning,multi-agent systems,and autonomous decision-making frameworks,particularly those leveraging large language models(LLMs),contrasting these with traditional AI or purely statistical models.Our primary goals are to consolidate current knowledge,identify significant trends and architectural approaches,review the practical efficiency and impact of current applications,and delineate key challenges and promising future research directions.The increasing sophistication of AI agents offers unprecedented opportunities for innovation in finance,yet presents complex technical,ethical,and regulatory challenges that demand careful consideration and proactive strategies.This review aims to provide a comprehensive understanding of this rapidly evolving landscape,highlighting the role of agent-based AI in the ongoing transformation of the financial industry,and is intended to serve financial institutions,regulators,investors,analysts,researchers,and other key stakeholders in the financial ecosystem.
文摘The chemical structure of polyamide 6(PA6)dictates that only 50%of hydrogen bonds participate in crystallization during the crystallization process,resulting in the properties of its products being significantly dependent on the molding process.Therefore,the design and development of nucleating agents suitable for PA6 holds great practical significance for high-performance PA6 materials.Amide-based nucleating agents can effectively improve the crystallization rate by increasing intermolecular hydrogen bond density.Further introduction of hydroxyl groups can enhance the hydrogen bonding interactions between the nucleating agent and PA6.In this study,a hydroxyl-containing amidebased nucleating agent,BHT,was designed and synthesized using a tyramine-based biomass as the raw material.These results demonstrated that BHT exhibited good structural compatibility with PA6.After adding 1 wt%BHT,the crystallization temperature of PA6 increased from 170.9℃to 193.3℃,the crystallinity increased 16.6%,the heat distortion temperature and Vicat softening temperature rose to 89.5 and 187.8℃,respectively,the haze decreased to 46%,achieving the synergistic optimization of mechanical,thermal,and optical properties.The in situ time-resolved FTIR results indicated that the addition of BHT increased the enthalpy of hydrogen bond formation during the nucleation stage,facilitated the segmental conformation adjustment of PA6,and enhanced the molar concentration of trans-conformations,ultimately leading to an improvement in the crystallization rate.
基金supported by the National Natural Science Foundation of China (NSFC grant no. 62474028, 52130304, and62222503)the Natural Science Foundation of Sichuan Province(2025ZNSFSC0037, 2025ZNSFSC1460, and 2024NSFSC1447)+1 种基金the National Key R and D Program of China (2023YFB2604101)sponsored by the Sichuan Province Key Laboratory of Display Science and Technology
文摘The crystallization and aggregation characteristics of the active layer components in organic solar cells(OSCs)are one of the core factors determining photovoltaic performance,influencing the entire process from light absorption to charge separation,transport,and ultimately charge collection.Dynamic changes in crystallization and aggregation states can also disrupt the microstructure of the active layer,thus shortening the lifetime of the cell.In this study,a morphology modulation strategy is proposed to regulate the crystallization kinetics of non-fullerene acceptors by employing the polymer molecule PYIT as a nucleating agent.An appropriate amount of PYIT was first completely dissolved with the non-fullerene acceptor Y6 and left to stand for 24 h,followed by the fabrication of layer-by-layer processed OSCs.Experiments demonstrated that high crystallinity of PYIT allows it to act as a crystallization nucleus,promoting the crystallization,orientation consistency,and ordered stacking of the acceptor.These nanoscale structural optimizations facilitate efficient charge transport,enhance exciton dissociation efficiency,and suppress unfavorable energetic disorder.Consequently,not only was the power conversion efficiency(PCE)of D18-Cl/Y6-based layer-by-layer processed OSC increased from 18.08%to 19.13%,but the atmospheric stability and long-term lifetime of the OSCs were also significantly improved.Notably,this strategy is also applicable to indoor OSCs,and the PYIT-optimized device can achieve a PCE of 27.0%under 1000 lux light-emitting diode(LED,3200K)irradiation,which is superior to that of the control device(24.2%).This work develops a crystal engineering strategy that is able to simultaneously optimize the microscopic morphology and charge dynamics properties in OSCs,thereby achieving simultaneous improvement in efficiency and stability.
基金supported by the Zhejiang Province Leading Geese Plan(Grant No.2025C02025)the Guangdong Province Primary and Secondary School Teachers’Digital Literacy Enhancement Project 2025(Grant No.GDSZSYKT2025244).
文摘With the rise of AI-assisted education,many instructors and engineers seek to deliver high-quality programming courses online.However,crafting effective programming lectures remains a challenge,particularly for instructors lacking pedagogical training or multilingual fluency.We present CourseAgent,a prompt-driven framework that leverages large language models(LLMs)to automatically generate Python tutorials,structured lecture scripts,and accompanying audio narrations.CourseAgent accepts raw code as input and transforms it into segmented,well-commented code blocks,adapting content to different difficulty levels and languages via prompt customization.Our system supports multilingual instruction(e.g.,Chinese,English),fine-grained control of pedagogical depth,and auto-generation of lecture videos.We evaluate the output generated by CourseAgent using real student feedback and feedback from in-service teachers,alongside automated assessments from LLMs.These evaluations demonstrate that the materials produced by CourseAgent are coherent,pedagogically sound,and comparable in quality to those created by experienced instructors.CourseAgent lowers the barrier to quality programming education and shows promise for scalable,personalized,and language-adaptive content generation.
基金supported by the National Natural Science Foundation of China(No.22176200)the Industrial Innovation Entrepreneurial Team Project of Ordos 2021.
文摘Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management.
基金sponsored by the Department of Defense,Defense Threat Reduction Agency under the Materials Science in Extreme Environments University Research Alliance,HDTRA1-20-2-0001。
文摘Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl methylphosphonate(DIMP),a commonly used CWA surrogate,is widely studied to enhance our understanding of CWA behavior.The prevailing thermal decomposition model for DIMP,developed approximately 25 years ago,is based on data collected in nitrogen atmospheres at temperatures ranging from 700 K to 800 K.Despite its limitations,this model continues to serve as a foundation for research across various thermal and reactive environments,including combustion studies.Our recent experiments have extended the scope of decomposition analysis by examining DIMP in both nitrogen and zero air across a lower temperature range of 175℃ to 250℃.Infrared spectroscopy results under nitrogen align well with the established model;however,we observed that catalytic effects,stemming from decomposition byproducts and interactions with stainless steel surfaces,alter the reaction kinetics.In zero air environments,we observed a novel infrared absorption band.Spectral fitting suggests this band may represent a combination of propanal and acetone,while GCMS analysis points to vinyl formate and acetone as possible constituents.Although the precise identity of these new products remains unresolved,our findings clearly indicate that the existing decomposition model cannot be reliably extended to lower temperatures or non-nitrogen environments without further revisions.
