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Journal of Magnesium and Alloys 2024年第1期12卷 225-236页

作者： Shuo wang Daokui Xu Dongliang wang Zhiqiang Zhang Baojie wang Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Engineering Research Center of Advanced Materials Preparing Technology Ministry of EducationNortheastern UniversityShenyang110819China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Binzhou Institute of Technology BinzhouShandong Province256606China Shandong Key Laboratory of Advanced Aluminium Materials and Technology BinzhouShandong Province256606China

Through exploring the stress corrosion cracking(SCC)behaviors of the as-cast Mg-8%Li and Mg-8%Li-6%Zn-1.2%Y alloys in a 0.1 M NaCl solution,it revealed that the SCC susceptibility index(I_(SCC))of the Mg-8%Li alloy was 47%,whilst the I_(SCC)of the Mg-8%Li-6%Zn-1.2%Y alloy was 68%.Surface,cross-sectional and fractography observations indicated that for the Mg-8%Li alloy,theα-Mg/β-Li interfaces acted as the preferential crack initiation sites and propagation paths during the SCC *** regard to the Mg-8%Li-6%Zn-1.2%Y alloy,the crack initiation sites included the I-phase and the interfaces of I-phase/β-Li andα-Mg/β-Li,and the preferential propagation paths were the I-phase/β-Li andα-Mg/β-Li ***,the SCC of the two alloys was concerned with hydrogen embrittlement(HE)mechanism.

关键词： Magnesium-lithium alloy Stress corrosion cracking I-phase Fracture analysis

Physical mechanism of the rapid increase in intense and long-lived extreme heatwaves in the Northern Hemisphere since 1980

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Science China Earth Sciences 2024年第7期67卷 2103-2121页

作者： Yuqing wang Wen ZHOU Chunzai wang Key Laboratory of Polar Atmosphere-ocean-ice System for Weather and Climate of the MOE Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric SciencesFudan UniversityShanghai 200438China Key Laboratory for Polar Science of the MNR Polar Research Institute of ChinaShanghai 201209China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Global Ocean and Climate Research Center South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Since 1980,both the intensity and duration of summer heatwaves in the middle and high latitudes of the Northern Hemisphere have significantly increased,leading this region to become a critical area for a significant increase in the frequency of intense and long-lived extreme *** found that stronger and more persistent high-pressure systems and lower soil moisture before the events were the main drivers of intense and long-lived extreme heatwaves in western Europe and the middle and high latitudes of North ***,in eastern Europe and Siberia,lower cloud cover before events is also a main driver of this type of extreme heatwave,in addition to the above *** factors are coupled with each other and can change heatwave intensity and duration by influencing surface radiation processes during *** the self-organizing map classification method,we found that 6 weather patterns with increased frequency,intensity,and duration were the main dynamic reasons leading to the increase in intense and long-lived extreme heatwaves after *** addition,the decrease in summer average soil moisture in most areas of the mid-high latitudes of the Northern Hemisphere and the decrease in average cloud cover in eastern Europe and Siberia are found to be the main thermodynamic reasons leading to the increase in these extreme heatwaves.

关键词： High intensity Long duration Extreme heatwaves High pressure system Soil moisture Cloud cover

Effect of Operation Parameters on the Thermal Characteristics in a Planar Solid Oxide Fuel Cell

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Journal of Thermal Science 2024年第5期33卷 1974-1989页

作者： wang Mingyuan wang Ke wang Yongqing CHEN Jiangshuai AN Bo TU Shantung School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Process Heat Transfer and Energy Saving of Henan Province Zhengzhou UniversityZhengzhou 450002China School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Pressure Systems and Safety(MOE) East China University of Science&TechnologyShanghai 200237China

Effective operation strategies in the solid oxide fuel cell(SOFC)can adjust the spatial distribution of temperature gradient favoring the long-term *** investigate the effects of different operating conditions on the thermal behavior inside SOFC,a three-dimensional model is developed in this *** model is verified by comparing it with the experimental *** heat generation rate and its variation under different operating conditions are *** combined effects of operating voltage and gas temperature are considered to be the key factor influencing the temperature *** to the original case,the temperature of SOFC decreases by 21.4 K when the fuel velocity reaches 5 m/*** the maximum temperature gradient increases by21.2%.Meanwhile,higher fuel velocities can eliminate about 32%of the area with higher temperature *** when the oxidant velocity reaches 7.5 m/s,the peak temperature gradient effectively decreases by 16.59%.Simultaneous adjustment of the oxidant and fuel velocities can effectively reduce the peak temperature gradient and increase the safety *** effects of operation conditions on the temperature gradient of the cell are clarified in this study,which can be a reference for further research on the reliability of SOFCs.

关键词： SOFC heat generation temperature gradient distribution heat source thermal behavior

Pushing the boundaries: an interview with Dae-Hyun Kim on terahertz devices

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National Science Review 2024年第3期11卷 42-45页

作者： Defu wang the Center for Carbon-based Electronics School of Electronics Peking University

Ⅲ–Ⅴ compound semiconductors, such as InGaAs/InAlAs, exhibit exceptional carrier transport properties, establishing them as fundamental elements in terahertz(THz) applications crucial for the development of 6G netwo...

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广东三水盆地火山岩:地球化学特征及成因——兼论火山岩性质的时空演化和南海形成的深部过程

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大地构造与成矿学 2006年第1期30卷 72-81页

作者：肖龙周海民董月霞曾广策王方正中国科学院边缘海地质重点实验室广东广州510640 中国石油冀东油田分公司河北唐山063004 中国石油冀东油田勘探开发研究院河北唐山063004 中国地质大学地球科学学院湖北武汉430074

位于中国东南部的三水盆地、珠江口盆地、雷琼半岛和北部湾地区广泛分布新生代火山岩。火山岩的形成时间具有从内陆向沿海变新的特点,早第三纪三水和珠江口盆地火山岩具有由玄武岩与粗面岩-流纹岩构成的双峰式特点。其中玄武岩和粗面岩... 详细信息

位于中国东南部的三水盆地、珠江口盆地、雷琼半岛和北部湾地区广泛分布新生代火山岩。火山岩的形成时间具有从内陆向沿海变新的特点,早第三纪三水和珠江口盆地火山岩具有由玄武岩与粗面岩-流纹岩构成的双峰式特点。其中玄武岩和粗面岩的微量元素和稀土元素的配分形式相似,富集大离子亲石元素并且有相似的εNd(T)同位素组成(2.34～6.4),说明它们来自相同的地幔源区,为同源岩浆演化的产物。玄武岩和粗面岩经历了不同的结晶分异过程,其中玄武岩在较深部岩浆房中经历橄榄石和单斜辉石为主的分离结晶作用,而粗面岩则是在浅部岩浆房中由玄武岩浆分异形成的过渡性岩浆再经过强烈的钾长石和斜长石、以及磷灰石的结晶分异形成的。晚第三纪珠江口盆地和北部湾火山岩、雷琼半岛第四纪火山岩则由碱性和拉斑玄武岩构成。这些火山岩的形成时间和地球化学和同位素特征表明它们经历了连续的软流圈地幔上涌和部分熔融过程,受控于自晚中生代以来的地幔柱构造。南海的形成是地幔柱活动引起的地幔上涌和大陆裂解作用的结果。

关键词：火山岩地球化学地幔柱三水盆地珠江口盆地南海

Evolution of artificial ion channels

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National Science Review 2024年第1期11卷 72-73页

作者： Yugang wang School of Physics Peking University

Protein ion channels on a cell membrane generate action potentials for cellular signal transduction, and regulate biological activities during life. Since the discovery of the asymmetric ion transport phenomenon in quartz nanopipettes by Bard and colleagues [1], synthetic nanofluidic materials and devices have attracted a lot of research interests from the scientific community,

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特发性右心室流出道室性心律失常射频消融治疗即刻成功率的影响因素分析

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中华心血管病杂志 2018年第6期46卷 464-469页

作者：陈刚李晓飞樊晓寒张奎俊王方正姚焰中国医学科学院北京协和医学院国家心血管病中心阜外医院心律失常中心 100037

目的探讨特发性右心室流出道室性心律失常射频消融治疗即刻成功率的影响因素。方法回顾性纳入阜外医院2009年2月至2013年1月经临床及电生理检查明确诊断为特发性右心室流出道室性心律失常并接受射频消融治疗的患者468例。通过病案室查... 详细信息

目的探讨特发性右心室流出道室性心律失常射频消融治疗即刻成功率的影响因素。方法回顾性纳入阜外医院2009年2月至2013年1月经临床及电生理检查明确诊断为特发性右心室流出道室性心律失常并接受射频消融治疗的患者468例。通过病案室查询纸质或电子病历收集入选者基线临床资料，包括年龄、性别、吸烟史、饮酒史、血压、心率、入院前口服抗心律失常药物史、术前心电图、超声心动图、实验室检查结果以及临床合并症等。依据解剖和电生理特点将心律失常起源部位分为间隔部、前壁、后壁、游离壁、外膜和右心室流出道-主动脉根部。采用单因素和多因素logistic回归分析消融治疗即刻成功率的影响因素。结果研究最终纳入患者468例，年龄（40.4±13.3）岁。射频消融治疗的即刻成功率为89.3%（418/468），根据是否成功将患者分为消融成功组（n=418）和消融失败组（n=50）。消融成功组患者中女性和室性心律失常起源部位为间隔部的比例高于消融失败组（χ2值分别为6.35和6.99，P值分为别为0.01和0.005），而起源部位为心外膜的比例则低于消融失败组（χ2=25.53，P〈0.001），其他起源部位两组间差异无统计学意义（P均〉0.05）。多因素logistic回归分析显示，性别不是射频消融治疗即刻成功率的独立影响因素（OR=1.76，95%CI0.93-3.33，P=0.08），而室性心律失常起源部位则是射频消融治疗即刻成功率的独立影响因素，右心室流出道-主动脉根部和心外膜起源的患者消融即刻不成功的比率分别为间隔部的2.82和9.26倍（OR=2.82,95%CI1.05-7.57，和OR=9.26，95%CI3.60-23.86）。结论特发性右心室流出道室性心律失常患者总体射频消融治疗即刻成功率较高，但心外膜和右心室流出道-主动脉根部起源者成功率较低，心律失常起源部位是射频消融治疗即刻成功率的独立影响因素。

关键词：导管消融术室性心律失常

Stereoselective recognition of morphine enantiomers by μ-opioid receptor

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National Science Review 2024年第3期11卷 183-191页

作者： Yibo wang Van A.Ngo Xiaohui wang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of Sciences Advanced Computing for Life Sciences and Engineering Group Science Engagement Section National Center for Computational Sciences Oak Ridge National Lab School of Applied Chemistry and Engineering University of Science and Technology of China Beijing National Laboratory for Molecular Sciences

Stereospecific recognition of chiral molecules plays a crucial role in biological systems. The μ-opioid receptor（MOR） exhibits binding affinity towards（-）-morphine, a well-established gold standard in pain management, while it shows minimal binding affinity for the（+）-morphine enantiomer, resulting in a lack of analgesic activity. Understanding how MOR stereoselectively recognizes morphine enantiomers has remained a puzzle in neuroscience and pharmacology for over half-a-century due to the lack of direct observation techniques. To unravel this mystery, we constructed the binding and unbinding processes of morphine enantiomers with MOR via molecular dynamics simulations to investigate the thermodynamics and kinetics governing MOR's stereoselective recognition of morphine enantiomers. Our findings reveal that the binding of（-）-morphine stabilizes MOR in its activated state, exhibiting a deep energy well and a prolonged residence time. In contrast,（+）-morphine fails to sustain the activation state of ***, the results suggest that specific residues, namely D1142.50and D1473.32, are deprotonated in the active state of MOR bound to（-）-morphine. This work highlights that the selectivity in molecular recognition goes beyond binding affinities, extending into the realm of residence time.

关键词： stereoselective recognition thermodynamics and kinetics residence time morphine enantiomers μ-opioid receptor

Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 131-140页

作者： Zhongyang wang Youqing wang Zdzisław Kowalczuk the College of Information Science and Technology Beijing University of Chemical TechnologyBeijing 100029China IEEE the Department of Robotics and Decision Systems Faculty of ElectronicsTelecommunications and InformaticsGdańsk University of TechnologyGdansk 80-233Poland

In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection.

关键词： Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)

Steel-refractory reactions in lanthanum-,cerium-,and ytrium-added steels

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Journal of Iron and Steel Research International 2024年第6期31卷 1473-1485页

作者： Jian Kang Hong-po wang Yu wang College of Materials Science and Engineering Chongqing UniversityChongqing 400044China The State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

A systematic experimental study was conducted on the similarities and differences in the reactions between commonly used rare earth elements(REEs)and frequently used refractories in the steelmaking *** results indicate that the reaction behaviors of La,Ce,and Y with MgO,Al_(2)O_(3),and MgO·Al_(2)O_(3) crucibles differed *** consumption rates of La,Ce,and Y in the molten steel were in descending order of La>Ce>Y for smelting with all three kinds of *** the REEs reacted with the crucible,the contents of Mg and Al showed a trend of first increasing and then *** laboratory-scale smelting conditions,the reactions related to REEs were dominated by steel-crucible reactions,and the contact area between the unit mass of molten steel and refractory materials mainly determined the consumption rates of ***-and Ce-crucible reactions generated loose and porous reaction interfaces;however,Y-crucible reactions generated a dense Y_(2)O_(3) layer,dramatically suppressing the consumption rate of *** calculation indicated that the reactions between rare earth and different refractory materials were first-order *** crucible materials significantly affected the product type and morphology of the steel-crucible reaction interfaces,thereby influencing the consumption rate of *** reactions between REEs and refractories must be seriously considered,especially for small-scale smelting.

关键词： Rare earth Inclusion Refractory Thermodynamics Dynamics