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激光功率对3/4H SUS301和SUS316异种不锈钢激光点焊成形特征及组织性能的影响

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焊管 2024年第5期47卷 33-39页

作者：董智龙彭丽雯侯军才张秋美张会陕西理工大学材料科学与工程学院陕西汉中723001

采用准连续激光器对测力传感器的3/4H SUS301弹性体和SUS316支撑体进行异种不锈钢激光焊接,探讨了激光功率对点焊接头成形特征和力学性能的影响。研究表明,采用准连续激光模式,在脉冲时间为2 ms、激光功率为180 W至270 W范围内,弹性体... 详细信息

采用准连续激光器对测力传感器的3/4H SUS301弹性体和SUS316支撑体进行异种不锈钢激光焊接,探讨了激光功率对点焊接头成形特征和力学性能的影响。研究表明,采用准连续激光模式,在脉冲时间为2 ms、激光功率为180 W至270 W范围内,弹性体焊后的角变形量随着激光功率的增大而增大,激光功率为270 W时弹性体焊后的角变形远低于传感器容许的变形量。当激光功率为210W时,在焊接界面处产生气孔缺陷,焊接功率增大至270 W时,在匙孔底部形成严重的气孔缺陷。焊缝内部以胞状晶方式生长,从熔合区两侧向焊缝中心生长为粗大的柱状晶,焊缝中心为等轴状的树枝晶,随着激光功率的增大,等轴晶区域的宽度减小。焊缝区承受较高的焊接热量使得焊缝区内形变组织发生不完全再结晶,致使形变诱发马氏体相变被抑制,α'马氏体含量降低。点焊接头的剪切力随着激光功率先增大后减小,当激光功率为250 W时,接头的剪切力达到最大值0.49 kN,远高于行业要求。

关键词：激光焊接点焊晶粒形态气孔缺陷显微组织

Chlorfenapyr poisoning:mechanisms,clinical presentations,and treatment strategies

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World Journal of Emergency Medicine 2024年第3期15卷 214-219页

作者： Ji Cheng Yulu Chen Weidong Wang Xueqi Zhu Zhenluo Jiang peng Liu liwen Du Emergency Department Ningbo No.2 HospitalNingbo 315010China

BACKGROUND:Chlorfenapyr is used to kill insects that are resistant to organophosphorus insecticides.Chlorfenapyr poisoning has a high mortality rate and is difficult to treat.This article aims to review the mechanisms,clinical presentations,and treatment strategies for chlorfenapyr poisoning.DATA RESOURCES:We conducted a review of the literature using PubMed,Web of Science,and SpringerLink from their beginnings to the end of October 2023.The inclusion criteria were systematic reviews,clinical guidelines,retrospective studies,and case reports on chlorfenapyr poisoning that focused on its mechanisms,clinical presentations,and treatment strategies.The references in the included studies were also examined to identify additional sources.RESULTS:We included 57 studies in this review.Chlorfenapyr can be degraded into tralopyril,which is more toxic and reduces energy production by inhibiting the conversion of adenosine diphosphate to adenosine triphosphate.High fever and altered mental status are characteristic clinical presentations of chlorfenapyr poisoning.Once it occurs,respiratory failure occurs immediately,ultimately leading to cardiac arrest and death.Chlorfenapyr poisoning is diflcult to treat,and there is no specific antidote.CONCLUSION:Chlorfenapyr is a new pyrrole pesticide.Although it has been identified as a moderately toxic pesticide by the World Health Organization(WHO),the mortality rate of poisoned patients is extremely high.There is no specific antidote for chlorfenapyr poisoning.Therefore,based on the literature review,future efforts to explore rapid and effective detoxification methods,reconstitute intracellular oxidative phosphorylation couplings,identify early biomarkers of chlorfenapyr poisoning,and block the conversion of chlorfenapyr to tralopyril may be helpful for emergency physicians in the diagnosis and treatment of this disease.

关键词： Chlorfenapyr poisoning Mechanism Clinical presentation Treatment

An improved estimation of distribution algorithm for multi-compartment electric vehicle routing problem

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Journal of Systems Engineering and Electronics 2021年第2期32卷 365-379页

作者： SHEN Yindong peng liwen LI Jingpeng Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China Division of Computing Science and Mathematics University of StirlingStirling FK94LAUK

The multi-compartment electric vehicle routing problem(EVRP)with soft time window and multiple charging types(MCEVRP-STW&MCT)is studied,in which electric multi-compartment vehicles that are environmentally friendly but need to be recharged in course of transport process,are employed.A mathematical model for this optimization problem is established with the objective of minimizing the function composed of vehicle cost,distribution cost,time window penalty cost and charging service cost.To solve the problem,an estimation of the distribution algorithm based on Lévy flight(EDA-LF)is proposed to perform a local search at each iteration to prevent the algorithm from falling into local optimum.Experimental results demonstrate that the EDA-LF algorithm can find better solutions and has stronger robustness than the basic EDA algorithm.In addition,when comparing with existing algorithms,the result shows that the EDA-LF can often get better solutions in a relatively short time when solving medium and large-scale instances.Further experiments show that using electric multi-compartment vehicles to deliver incompatible products can produce better results than using traditional fuel vehicles.

关键词： multi-compartment vehicle routing problem electric vehicle routing problem(EVRP) soft time window multiple charging type estimation of distribution algorithm(EDA) Lévy flight

Risk assessment of agricultural green water security in Northeast China under climate change

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Science China Earth Sciences 2024年第7期67卷 2178-2194页

作者： Jingxuan SUN Guangxin ZHANG Yanfeng WU liwen CHEN peng QI Boting HU Yijun XU Northeast Institute of Geography and Agroecology.Chinese Academy of Sciences Changchun 130102China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Renewable Natural Resources Louisiana State University Agricultural Center227 Highland RoadBaton RougeLA 70803USA

Northeast China is an important base for grain production,dominated by rain-fed agriculture that relies on green water.However,in the context of global climate change,rising regional temperatures,changing precipitation patterns,and increasing drought frequency pose threats and challenges to agricultural green water security.This study provides a detailed assessment of the spatiotemporal characteristics and development trends of green water security risks in the Northeast region under the base period(2001-2020)and the future(2031-2090)climate change scenarios(SSP245 and SSP585)using the green water scarcity(GWS)index based on raster-scale crop spatial distribution data,Delta downscaling bias-corrected ERA5 data,and CMIP6 multimodal data.During the base period,the green water risk-free zone for dry crops is mainly distributed in the center and east of the Northeast region(72.4% of the total area),the low-risk zone is primarily located in the center(14.0%),and the medium-risk(8.3%)and high-risk(5.3%)zones are mostly in the west.Under SSP245 and SSP585 future climate change scenarios,the green water security risk shows an overall expansion from the west to the center and east,with the low-risk zone increasing to 21.6% and 23.8%,the medium-risk zone increasing to 16.0% and 17.9%,and the high-risk zone increasing to 6.9% and 6.8%,respectively.Considering dry crops with GWS greater than 0.1 as in need of irrigation,the irrigated area increases from 27.6%(base period)to 44.5%(SSP245)and 48.6%(SSP585),with corresponding increases in irrigation water requirement(IWR)of 4.64 and 5.92 billion m~3,respectively,which further exacerbates conflicts between supply and demand of agricultural water resources.In response to agricultural green water security risks,coping strategies such as evapotranspiration(ET)-based water resource management for dry crops and deficit irrigation are proposed.The results of this study can provide scientific basis and decision support for the development of Northeast irrigated agriculture and the cons

关键词： Climate change Food security Green water security risk Irrigation water requirement Green water scarcity

A thermodynamic view on the in-situ carbon dioxide reduction by biomass-derived hydrogen during calcium carbonate decomposition

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Chinese Journal of Chemical Engineering 2024年第4期68卷 231-240页

作者： peng Jiang Hao Zhang Guanhan Zhao Lin Li Tuo Ji liwen Mu Xiaohua Lu Jiahua Zhu State Key Laboratory of Materials-oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

In the carbonate industry,deep decarbonization strategies are necessary to effectively remediate CO_(2).These strategies mainly include both sustainable energy supplies and the conversion of CO_(2)in downstream processes.This study developed a coupled process of biomass chemical looping H2 production and reductive calcination of CaCO_(3).Firstly,a mass and energy balance of the coupled process was established in Aspen Plus.Following this,process optimization and energy integration were implemented to provide optimized operation conditions.Lastly,a life cycle assessment was carried out to assess the carbon footprint of the coupled process.Results reveal that the decomposition temperature of CaCO_(3)in an H_(2)atmosphere can be reduced to 780℃(generally around 900℃),and the conversion of CO_(2)from CaCO_(3)decomposition reached 81.33%with an H2:CO ratio of 2.49 in gaseous products.By optimizing systemic energy through heat integration,an energy efficiency of 86.30%was achieved.Additionally,the carbon footprint analysis revealed that the process with energy integration had a low global warming potential(GWP)of-2.624 kg·kg^(-1)(CO_(2)/CaO).Conclusively,this work performed a systematic analysis of introducing biomass-derived H_(2)into CaCO_(3)calcination and demonstrated the positive role of reductive calcination using green H_(2)in mitigating CO_(2)emissions within the carbonate industry.

关键词： Biomass CaCO_(3)reductive calcination Chemical looping Hydrogen production Carbon footprint Thermodynamics process

Towards carbon neutrality of calcium carbide-based acetylene production with sustainable biomass resources

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Green Energy & Environment 2024年第6期9卷 1068-1078页

作者： peng Jiang Guanhan Zhao Hao Zhang Tuo Ji liwen Mu Xiaohua Lu Jiahua Zhu State Key Laboratory of Materials-oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from coal.Here,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium looping.For comparison,a coal-to-acetylene process was also established by using coal as feedstock.The carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically analyzed.Moreover,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) furnace.Even though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA process.With sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA process.This work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier.

关键词： Biomass pyrolysis CO_(2)mitigation Calcium carbide Acetylene Calcium loop

1,12-cyclic apelin-12 ameliorates Ang II and Apelin-13-induced cardiac hypertrophy by reducing mitochondrial oxidative damage

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Chinese Medical Journal 2024年第6期137卷 749-751页

作者： Xueqian Ouyang Wei Chen Guolong peng Huimei Liu Sisi Fan Qin Li liwen Wang Linxi Chen Lanfang Li The Institute of Pharmacy and Pharmacology Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug ResearchUniversity of South ChinaHengyangHunan 421001China

To the Editor:Pathological cardiac hypertrophy is commonly stimulated by stress or induced by cardiovascular diseases,such as hypertension and myocardial infarction.A sustained pathological hypertrophic response can lead to declines in diastolic and systolic functions and eventually develop heart failure.Angiotensin II(Ang II)can mediate cardiac hypertrophy through the angiotensin II type 1 receptor(AT1R).^([1])

关键词： hypertrophy cardiac Ang

储能接入电气化铁路的拓扑及控制策略研究综述

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高电压技术 2023年第10期49卷 4069-4083页

作者：闵永智成柯袁佳歆王果曲锴彭莉雯兰州交通大学自动化与电气工程学院兰州730070 武汉大学电气与自动化学院武汉430072

随着“双碳”目标的提出和我国铁路里程的高速增长,节能增效已成为铁路未来的发展趋势。作为提升系统韧性与降低系统能耗的关键手段,储能大规模接入电气化铁路势在必行。为此,针对电气化铁路储能系统开展了系统性的研究工作,旨在为电气... 详细信息

随着“双碳”目标的提出和我国铁路里程的高速增长,节能增效已成为铁路未来的发展趋势。作为提升系统韧性与降低系统能耗的关键手段,储能大规模接入电气化铁路势在必行。为此,针对电气化铁路储能系统开展了系统性的研究工作,旨在为电气化铁路储能系统大规模工程应用提供一定的参考。首先,分析了电气化铁路储能系统选型原则,在实际应用过程中需结合牵引负荷功率特性、安装位置等多方面因素进行综合选型。其次,对不同供电方式下电气化铁路储能系统接入方案进行对比分析,为满足铁路系统大功率需求,储能系统的接入方案设计应满足更加高效、可靠、模块化、智能化的特点。然后,对基于储能的电气化铁路供电系统电能质量问题治理方案及控制策略进行了分析,储能系统的接入可有效改善电气化铁路供电系统电能质量。最后,总结了轨道交通储能技术示范项目的建设成果并对电气化铁路储能系统未来研究的关键问题进行展望。

关键词：电气化铁路储能系统储能接入位置储能接入拓扑电能质量综合补偿储能系统控制策略

罗伊氏乳杆菌抑制肠上皮细胞炎症反应和凋亡的作用及机制

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食品科学 2024年第6期45卷 113-119页

作者：陈鹏钟瑜娜于轹文胡瑾谢梅英广东生态工程职业学院广东广州510520

目的:探讨罗伊氏乳杆菌对肠上皮细胞炎症反应和凋亡的作用及相关机制。方法:通过免疫荧光和酶联免疫吸附检测罗伊氏乳杆菌对肠上皮细胞炎症反应和凋亡的影响;采用生物信息学分析、定量聚合酶链式反应和双荧光素酶报告基因等实验筛选罗... 详细信息

目的:探讨罗伊氏乳杆菌对肠上皮细胞炎症反应和凋亡的作用及相关机制。方法:通过免疫荧光和酶联免疫吸附检测罗伊氏乳杆菌对肠上皮细胞炎症反应和凋亡的影响;采用生物信息学分析、定量聚合酶链式反应和双荧光素酶报告基因等实验筛选罗伊氏乳杆菌发挥作用的下游微小核糖核酸(microRNA,miRNA);通过双荧光素酶报告基因和Western blot等实验筛选miR-196a下游靶基因及其功能。结果:罗伊氏乳杆菌能够抑制脂多糖引起的肠上皮细胞炎症反应和凋亡,进一步分析发现罗伊氏乳杆菌通过上调肠上皮细胞miR-196a抑制细胞炎症和凋亡,miR-196a通过靶向抑制程序性细胞死亡因子4(programmed cell death 4,PDCD4)基因表达发挥对肠上皮细胞的保护作用。结论:罗伊氏乳杆菌通过miR-196a靶向抑制PDCD4基因表达,减缓肠上皮细胞炎症反应和凋亡。

关键词：罗伊氏乳杆菌肠道健康微小核糖核酸炎症凋亡