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激光熔覆Ni基合金涂层组织性能的研究进展

特种铸造及有色合金 2023年第12期43卷 1613-1620页

作者：王修虎米国发李雷陈晓壮刘卫东张利超河南理工大学材料科学与工程学院上海电机学院材料学院上海仅博激光技术有限公司

镍基合金具有良好的耐高温、抗蠕变性,作为激光熔覆材料被广泛应用于各种高性能复杂结构件的快速修复及表面改性。激光增材制造镍基合金虽具有良好的硬度和耐高温性,但在苛刻的服役条件下同时承受高温和高速摩擦作用,熔覆层表面损耗仍... 详细信息

镍基合金具有良好的耐高温、抗蠕变性,作为激光熔覆材料被广泛应用于各种高性能复杂结构件的快速修复及表面改性。激光增材制造镍基合金虽具有良好的硬度和耐高温性,但在苛刻的服役条件下同时承受高温和高速摩擦作用,熔覆层表面损耗仍然很大,故镍基合金熔覆层的高温耐磨性需要进一步提高与优化。从激光熔覆工艺参数、合金元素含量、增强相、自润滑相及辅助处理对镍基合金激光熔覆层的高温耐磨性能的影响进行综合阐述,分析其所面临的主要难题并提出改进措施。

关键词：激光熔覆镍基合金高温耐磨性

High-resolution remote thermometry based on Bi^(3+)-doped 0D zinc halide hybrids

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Science China Chemistry 2024年第8期67卷 2599-2605页

作者： Cui-mi Shi Shu-Hua Xue Jin-Yun Wang Liang-Jin Xu Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of ChinaFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi^(3+)into the(MePPh_(3))_(2)ZnCl_(4) matrix. Through Bi^(3+)doping,the initially non-luminescent(MePPh_(3))_(2) ZnCl_(4) matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield(PLQY) of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi^(3+)is mainly responsible for the blue emission. Single crystals of Bi^(3+)-doped(MePPh_(3))_(2)ZnCl_(4) show an unusual correlation between photoluminescence(PL) lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K^(-1), representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

关键词： lead-free hybrids Bi^(3+)doping blue emission temperature sensing

Comparative analysis of thermodynamic and mechanical responses between underground hydrogen storage and compressed air energy storage in lined rock caverns

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International Journal of mining Science and Technology 2024年第4期34卷 531-543页

作者： Bowen Hu Liyuan Yu Xianzhen mi Fei Xu Shuchen Li Wei Li Chao Wei Tao Zhang State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Large Structure Health Monitoring and Control Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

Underground hydrogen storage(UHS)and compressed air energy storage(CAES)are two viable largescale energy storage technologies for mitigating the intermittency of wind and solar ***,it is meaningful to compare the properties of hydrogen and air with typical thermodynamic storage *** study employs a multi-physical coupling model to compare the operations of CAES and UHS,integrating gas thermodynamics within caverns,thermal conduction,and mechanical deformation around rock *** thermodynamic responses are validated using additional simulations and the field test *** and pressure variations of air and hydrogen within rock caverns exhibit similarities under both adiabatic and diabatic simulation *** reaches higher temperature and pressure following gas charging stage compared to air,and the ideal gas assumption may lead to overestimation of gas temperature and *** steel lining of CAES,the sealing layer(fibre-reinforced plastic FRP)in UHS is prone to deformation but can effectively mitigates stress in the sealing *** CAES,the first principal stress on the surface of the sealing layer and concrete lining is tensile stress,whereas UHS exhibits compressive stress in the same *** present research can provide references for the selection of energy storage methods.

关键词： Underground hydrogen storage Compressed air energy storage Mechanical response Thermodynamic response Lined rock caverns

JA-mediated MYC2/LOX/AOS feedback loop regulates osmotic stress response in tea plant

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Horticultural Plant Journal 2024年第3期10卷 931-946页

作者： Junyan Zhu Hongrong Chen Lu Liu Xiaobo Xia Xiaomei Yan Xiaozeng mi Shengrui Liu Chaoling Wei State Key Laboratory of Tea Plant Biology and Utilization/Key Laboratory of Tea Biology and Tea Processing of ministry of Agriculture/Anhui Provincial Laboratory of Tea Plant Biology and Utilization Anhui Agricultural UniversityHefeiAnhui 230036China

Osmotic stress caused by low-temperature,drought and salinity was a prevalent abiotic stress in plant that severely inhibited plant development and agricultural yield,particularly in tea *** acid(JA)is an important phytohormone involving in plant ***,underlying molecular mechanisms of JA modulated osmotic stress response remains *** this study,high concentration of mannitol induced JA accumulation and increase of peroxidase activity in tea *** transcriptome mined a JA signaling master,MYC2 transcription factor is shown as a hub regulator that induced by mannitol,expression of which positively correlated with JA biosynthetic genes(LOX and AOS)and peroxidase genes(PER).CsMYC2 was determined as a nuclei-localized transcription activator,furthermore,ProteinDNA interaction analysis indicated that CsMYC2 was positive regulator that activated the transcription of CsLOX7,CsAOS2,CsPER1 and CsPER3via bound with their promoters,*** of CsMYC2 expression resulted in a reduced JA content and peroxidase activity and osmotic stress tolerance of tea *** of CsMYC2 in Arabidopsis improved JA content,peroxidase activity and plants tolerance against mannitol ***,we proposed a positive feedback loop mediated by CsMYC2,CsLOX7 and CsAOS2 which constituted to increase the tolerance of osmotic stress through fine-tuning the accumulation of JA levels and increase of POD activity in tea plant.

关键词： Camellia sinensis Jasmonic acid(JA) MYC2 transcription factor Lipoxygenase(LOX) Osmotic stress Peroxidase(POD) Reactive oxygen species(ROS)

The carbon border adjustment mechanism is inefficient in addressing carbon leakage and results in unfair welfare losses

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Fundamental Research 2024年第3期4卷 660-670页

作者： Xinlu Sun Zhifu mi Lu Cheng D'Maris Coffman Yu Liu The Bartlett School of Sustainable Construction University College LondonLondon WC1E 7HBUnited Kingdom College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The European Commission has proposed a Carbon Border Adjustment Mechanism(CBAM)to reduce carbon leakage and create a level playing field for its domestic products and imported ***,the effectiveness of the proposal remains unclear,especially when it triggers threats of retaliation from trading partners of the European *** apply a Computable General Equilibrium model-Global Trade Analysis Project-to assess the economic and environmental impacts of different CBAM *** we show that the effectiveness of the CBAM to address carbon leakage risks is rather limited,and the CBAM raises concerns over global welfare costs,Correct to Gross Domestic Product(GDP)losses,and violation of equality *** retaliation leads to multiplied welfare losses,which would mostly be borne by poor *** results question the carbon leakage reduction effect of a unilateral trade policy and suggest that climate change mitigation still needs to be performed within the framework of international cooperation.

关键词： Carbon border adjustment mechanism Carbon leakage Climate change mitigation Floorcarbon price Trade retaliation

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四辊破碎机辊子的铸造工艺优化

热加工工艺 2009年第17期38卷 49-52页

作者：米国发王锦永王狂飞河南理工大学材料科学与工程学院河南焦作454003

在生产过程中发现破碎机辊子有缩孔、缩松缺陷,为查明原因,运用View Cast软件对其铸造工艺进行了分析,并对凝固过程进行了模拟。根据模拟结果,对其铸造工艺进行了修改,再次进行凝固模拟,制定出了合适的工艺。结果表明,优化工艺所设置的... 详细信息

在生产过程中发现破碎机辊子有缩孔、缩松缺陷,为查明原因,运用View Cast软件对其铸造工艺进行了分析,并对凝固过程进行了模拟。根据模拟结果,对其铸造工艺进行了修改,再次进行凝固模拟,制定出了合适的工艺。结果表明,优化工艺所设置的冒口、冷铁的尺寸和位置是合理的,有效解决了生产过程中出现的问题。

关键词：辊子 ViewCast 凝固模拟铸造工艺

Catalytic Peculiarity of Electrode/Polyelectrolyte Interfaces toward COReduction

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Wuhan University Journal of Natural Sciences 2024年

作者： mi Zhensheng WANG Gongwei ZHUANG Lin College of Chemistry and Molecular Sciences Hubei Key Lab of Electrochemical Power Sources Wuhan University

A prominent feature of modern electrochemical technologies, such as fuel cells, water electrolysis, and CO2 electrolysis, is to employ polyelectrolytes instead of liquid electrolytes. This shift not only mitigates risks like corrosion and leaks associated with liquid electrolytes, but also facilitates the construction of zero-gap membrane electrode assembly(MEA) devices. In the MEA setups, the anode and cathode are tightly pressed against a micron-thick polyelectrolyte membrane, which can significantly reduce internal resistance and enhance energy conversion efficiency.

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Time trends and disparities of obesity and related national policies and programs in Nepal:a systematic review

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Global Health Journal 2024年第2期8卷 46-57页

作者： Junxiang Wei Peng Nie Liwang Gao Yang mi Youfa Wang Department of Obstetrics Northwest Women's and Children's HospitalXi'anShaanxiChina School of Economics and Finance Xi'an Jiaotong UniversityXi'anShaanxiChina Center for Non-Communicable Disease Management Beijing Children's HospitalCapital Medical UniversityNational Center for Children's HealthBeijingChina Global Health Institute No.21 Hongren BuildingWest China Science and Technology lnnovation Harbour(iHarbour)Xi'anShaanxiChina School of Public Health Xi'an Jiaotong UniversityXi'anShaanxiChina

Objective Overweight and obesity prevalence has increased in low-income *** study systematically reviewed the obesity trend,disparities,and prevention and control efforts in *** We searched PubMed and Google Scholar for articles and reports published between January 1,2004 and December 31,*** information on National policies and programs related to obesity prevention was retrieved from governmental websites and consultation with relevant *** and obesity were defined using the World Health Organization body mass index cut ***-two studies and reports were *** Overall,overweight and obesity rates increased in all groups in Nepal although nationally representative data remained *** combined overweight and obesity(OW/OB)and obesity rates in women aged 15-49 years increased from 8.5%to 22.2%and from 0.9%to 5.1%between 2006 and 2016,***/OB and obesity rates in men were 17.1%and 2.5%based on data from the 2016 Demographic and Health ***/OB rate in under-five children increased from 0.6%to 2.8%between 2006 and *** rates for school-age(5-9 years)boys and girls in 2016 were 2.4%and 2.8%,respectively,and were 1.1%and 1.4%for male and female adolescents aged 10-19 years,***/OB prevalence was much higher among women,residents in urban areas and central provinces,and in higher socioeconomic status *** prevalence of OW/OB and obesity for 2030 in adults aged 15-49 was 44.7%and 8.3%,respectively,while it was 2.2%for OW/OB in preschool *** and direct interventions that specifically focused on obesity prevention and control are *** OW/OB prevalence in Nepal has increased during the past 1.8 decades,disproportionately affecting population *** interventions mostly focused on undernutrition with some indirect implications for obesity *** the future,Nepal needs to develop population-based programs for obesity

关键词： Nutrition transition Overweight Obesity Obesity prevention Systematic review Nepal

Ce及变质工艺对ZL101A合金组织的影响

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热加工工艺 2009年第3期38卷 10-13页

作者：米国发文涛龚海军河南理工大学材料科学与工程学院河南焦作454000

研究了Ce加入量、保温时间、变质温度和冷却速度对ZL101A合金组织的影响。实验结果表明,在金属型铸造条件下,加入质量分数为0.8%左右的Ce时,ZL101A合金具有最佳的变质效果,共晶硅全部变为细小点状,而且保温6h仍有一定的变质效果;适当提... 详细信息

研究了Ce加入量、保温时间、变质温度和冷却速度对ZL101A合金组织的影响。实验结果表明,在金属型铸造条件下,加入质量分数为0.8%左右的Ce时,ZL101A合金具有最佳的变质效果,共晶硅全部变为细小点状,而且保温6h仍有一定的变质效果;适当提高变质温度可以减少稀土Ce的用量,最佳变质温度为760℃;冷却速度对变质影响很大,当冷却速度为0.8℃/s时没有任何变质效果。

关键词： ZL101A合金稀土铈变质