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Chinese Medical Journal 2024年第10期137卷 1228-1230页

作者： Jing Wang Jian Wang Sizhe Gao Gang Liu Qian Wang Shujie Yan Boyi Zhou Yuan Yuan guodong Gao Bingyang Ji Department of Cardiopulmonary Bypass Fuwai hospitalNational Center for Cardiovascular DiseaseChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100037China

To the Editor:Veno-arterial extracorporeal membrane oxygenation(VA-ECMO)has been used as a bridge in patients with advanced heart failure(AdHF)while waiting for heart transplantation(HTx).Many studies reported by developed countries have confirmed the advantages of VA-ECMO in terms of bridge to left ventricular assist device(LVAD)or HTx,with stabilizing the condition and improving the possibility of further treatment of patients.[1-3]Recent data from the Extracorporeal Life Support Organization(ELSO)[4]indicated that ECMO used as a bridge has increased by 20.5%over a ***,to date,there are few studies on the bridge experience of VA-ECMO in the mainland of China.

关键词： patients arterial ventricular

Prediction of application scope of vertical fracture strike based on scattered wave fracture orientation function

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Global Geology 2015年第1期18卷 49-53页

作者： TANG Yufei LIU Yuwei LIU Xiwu yang guodong College of Geo-Exploration Science and Technology Jilin University Research Institute of Petroleum Exploration and Development Sinopec

Fracture system plays a very important role in the enrichment and accumulation of oil and gas in the reservoirs. Based on scattering wave information,Fracture Orientation Function( FOF) was built,which can be used to predict the fracture orientations. However,this method has only been verified by physical experiments without studies on the application scope. In this study,based on the linear sliding theory,FOF of the scattering wave was applied to the numerical simulation and the application scope was further studied according to fracture flexibility tensor. According to the fractures filled with gas and liquid,numerical simulation was conducted on the models with various fracture flexibilities. Numerical simulation results were used to inverse fracture orientation with the aid of the FOF of the scattering wave. The results show that it is workable to predict the vertical fracture orientation with the FOF of the scattering wave. Application of this method is more effective when the fractures are filled with gas than liquid. Moreover,the application scope can be predicted by the fracture flexibility.

关键词：裂缝方位散射波应用预测骨折垂直数值模拟断裂系统

The dynamic surface evolution of halide perovskites induced by external energy stimulation

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National Science Review 2024年第4期11卷 185-194页

作者： Feiyu Cheng Pengdong Wang Chenzhe Xu Qingliang Liao Suicai Zhang Haochun Sun Wenqiang Fan guodong Liu Zhiyun Li Yaping Kong Li Wang Fangsen Li Zhuo Kang Yue Zhang Academy for Advanced Interdisciplinary Science and Technology State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing Key Laboratory for Advanced Energy Materials and Technologies Key Laboratory of Advanced Materials and Devices for Post-Moore ChipsMinistry of EducationBeijing Advanced Innovation Center for Materials Genome Engineering School of Materials Science and EngineeringUniversity of Science and Technology Beijing Vacuum Interconnected Nanotech Workstation(Nano-X) Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of Sciences Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences

Tracking the dynamic surface evolution of metal halide perovskite is crucial for understanding the corresponding fundamental principles of photoelectric properties and intrinsic instability. However, due to the volatility elements and soft lattice nature of perovskites, several important dynamic behaviors remain unclear. Here, an ultra-high vacuum（UHV） interconnection system integrated by surface-sensitive probing techniques has been developed to investigate the freshly cleaved surface of CH3NH3PbBr3in situ under given energy stimulation. On this basis, the detailed three-step chemical decomposition pathway of perovskites has been clarified. Meanwhile, the evolution of crystal structure from cubic phase to tetragonal phase on the perovskite surface has been revealed under energy stimulation. Accompanied by chemical composition and crystal structure evolution, electronic structure changes including energy level position,hole effective mass, and Rashba splitting have also been accurately determined. These findings provide a clear perspective on the physical origin of optoelectronic properties and the decomposition mechanism of perovskites.

关键词： metal halide perovskite external energy stimulation surface dynamic evolution surface electronic structure ultra-high vacuum interconnection system

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机器人轨迹纠偏控制方法研究

机器人 2017年第3期39卷 292-297页

作者：景奉水杨超杨国栋谭民中国科学院自动化研究所复杂系统管理与控制国家重点实验室北京100190 中国科学院大学北京100049

为减小机器人在执行轨迹跟踪任务过程中末端产生的位姿误差,在建立机器人轨迹纠偏系统模型的基础上,提出了一种积分型纠偏控制器实现方案.该方案直接在机器人的关节空间上对误差进行补偿.基于前述模型和一系列假设,首先从数学上证明了比... 详细信息

为减小机器人在执行轨迹跟踪任务过程中末端产生的位姿误差,在建立机器人轨迹纠偏系统模型的基础上,提出了一种积分型纠偏控制器实现方案.该方案直接在机器人的关节空间上对误差进行补偿.基于前述模型和一系列假设,首先从数学上证明了比例-积分纠偏控制器能够使纠偏误差以负指数收敛,进而说明积分型纠偏控制器的有效性.实验结果表明:通过设置合适的参数,在初始轨迹最大偏差为8 mm的情况下,纠偏控制后偏差均方根值小于0.07 mm,最大值小于0.4 mm.

关键词：轨迹跟踪轨迹纠偏纠偏控制运动规划机器人

内水压力对输水盾构隧洞复合衬砌结构影响研究

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现代隧道技术 2023年第4期60卷 33-42页

作者：孟庆辉封坤杨国栋何骁杨兆黄青富高崇西南交通大学交通隧道工程教育部重点实验室成都610031 云南省滇中引水工程有限公司昆明650000 中国电建集团昆明勘测设计研究院有限公司昆明650041 中铁十九局集团轨道交通工程有限公司北京101300

针对内水压力对盾构隧洞复合衬砌结构力学特性的影响,结合滇中引水工程龙泉倒虹吸隧洞,对复合衬砌壳-弹簧模型进行改进,对内水压作用下双层衬砌结构力学行为进行分析。结果表明,管片结构弯矩受内水压力影响较小,而管片轴力及纵向接头抗... 详细信息

针对内水压力对盾构隧洞复合衬砌结构力学特性的影响,结合滇中引水工程龙泉倒虹吸隧洞,对复合衬砌壳-弹簧模型进行改进,对内水压作用下双层衬砌结构力学行为进行分析。结果表明,管片结构弯矩受内水压力影响较小,而管片轴力及纵向接头抗弯刚度随内水压力增加而减小;二次衬砌轴力及弯矩受内水压力影响较大;内水压力对弯矩较大处接头抗弯刚度有较大影响,接头抗弯刚度最大减小47.97%;外部水土荷载作用下管片变形呈现竖向收敛、水平扩张趋势,充水后衬砌结构整体向下位移,竖向进一步收敛;内水压力作用下,管片与二次衬砌间以径向受压作用为主,当管片纵向接头受正弯矩作用时,压应力显著增加,受负弯矩作用时,径向相互作用力为零,层间存在分离趋势。

关键词：输水盾构隧洞双层衬砌内水压力接头刚度受力特征

后交叉韧带单束重建术股骨隧道角度与内侧副韧带损伤的相关性分析

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中国修复重建外科杂志 2022年第12期36卷 1492-1499页

作者：郭珈张东芳杨国栋曲迪张静戚超青岛大学青岛医学院山东青岛266073 青岛大学附属医院运动医学科山东青岛266103

目的探讨后交叉韧带重建术(posterior cruciate ligament reconstruction,PCLR)中,股骨隧道在股骨内侧髁的开口是否会造成内侧副韧带(medial collateral ligament,MCL)医源性损伤,并估计股骨隧道放置的安全角度。方法使用13具甲醛浸泡... 详细信息

目的探讨后交叉韧带重建术(posterior cruciate ligament reconstruction,PCLR)中,股骨隧道在股骨内侧髁的开口是否会造成内侧副韧带(medial collateral ligament,MCL)医源性损伤,并估计股骨隧道放置的安全角度。方法使用13具甲醛浸泡人体膝关节标本,捐赠者男8例,女5例;年龄49~71岁,平均61岁。仔细解剖每个膝关节标本股骨内侧区,明确MCL在股骨内侧走行与附着的区域,并沿此区域前缘作1条标记线,通过这条标记线将股骨内侧髁分割为MCL覆盖区和无MCL分布的相对安全区域。然后将膝关节标本的后交叉韧带(posterior cruciate ligament,PCL)切断以暴露PCL股骨附着区,在120°屈曲角度固定的膝关节标本上,模拟PCL单束重建术中股骨隧道制备,采用由内向外技术从膝关节内部的PCL股骨足迹处向股骨内侧方向进行股骨隧道钻孔,并通过轴面和冠状面两平面角度组合的方式实现不同方向股骨隧道的创建。选取15种角度组合[0°/30°、0°/45°、0°/60°、15°/30°、15°/45°、15°/60°、30°/30°、30°/45°、30°/60°、45°/30°、45°/45°、45°/60°、60°/30°、60°/45°和60°/60°(轴面/冠状面)],验证股骨隧道放置角度是否为损伤MCL的危险因素,并通过检验各角度组合产生的股骨隧道开口点与MCL前缘标记线的最短距离是否存在差异来估计股骨隧道放置的安全角度。结果在PCLR中创建股骨隧道时,存在MCL被股骨隧道出口损伤的风险,发生率为0~100%,当轴平面钻孔角度为0°和15°时,MCL损伤发生率高达69.23%~100%。并且股骨隧道放置角度不同,其MCL损伤发生率差异有统计学意义(χ^(2)=148.195,P<0.001)。通过组间比较发现,以45°/45°、45°/60°、60°/30°、60°/45°和60°/60°(轴面/冠状面)这5个角度组合创建的股骨隧道,其隧道出口点与标记线最短距离与0°/45°、0°/60°、15°/45°、15°/60°和30°/30°(轴面/冠状面)比较差异有统计学意义(P<0.05);进一步比较最短距离的中位数发现,这5个角度组合的股骨隧道出口点更远离标记线及其后方的MCL。结论在PCLR中股骨隧道的创建会造成MCL医源性损伤,且损伤风险受隧道角度影响,推荐以45°/45°、45°/60°、60°/30°、60°/45°和60°/60°(轴面/冠状面)角度组合创建股骨隧道,以降低MCL的医源性损伤风险。

关键词：后交叉韧带重建术股骨隧道内侧副韧带医源性损伤

构筑开放锡位点实现酸性增强的二甲醚羰基化丝光沸石催化剂设计

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Engineering 2024年第4期35卷 104-114页

作者： Ying Li Man Yu guodong Qi Yunduo Liu Jing Lv Shouying Huang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China National Center for Magnetic Resonance in Wuhan&State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics&Key Laboratory of Magnetic Resonance in Biological Systems Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China Inner Mongolia Key Laboratory of Industrial Catalysis College of Chemical EngineeringInner Mongolia University of TechnologyHohhot 010051China

Due to their tunable acidity,shape selectivity,and excellent stability,zeolites are of great importance as solid acid materials in industrial *** the properties of the acid sites in zeolites allows for the rational design and fabrication of catalysts for target *** ether(DME)carbonylation,a critical chain-growth reaction for C1 resource utilization,is selectively catalyzed by the Brønsted acid sites within the eight-membered rings(8-MRs)of mordenite(MOR).It is anticipated that strengthening the Brønsted acidity—particularly in 8-MRs—will improve the catalytic performance of *** this work,density functional theory(DFT)calculations are first employed and the results used to design a modified MOR with stannum(Sn)and to predict the corresponding changes in *** by the theoretical studies,a series of Sn-modified MOR are synthesized via a defect-engineering and subsequent heteroatom-substitution *** partial desilication,isolated tetrahedral Sn species in an open configuration are successfully synthesized for the first time,within which tetrahedrally coordinated Al sites are *** acidic characterization is used to confirm that the acidity of the Brønsted acid sites is enhanced by the introduction of the Sn species;as a result,the sample exhibits excellent activity in DME carbonylation *** and DFT studies reveal that this strengthened acidity facilitates the adsorption of DME and reduces the activation barriers of DME dissociation and acetyl formation,accounting for the improved *** work demonstrates mechanistic insights into the promoting effects of strong acidity on DME carbonylation and offers a promising strategy to precisely control the acidic strength of zeolites.

关键词： Zeolite Sn modification Carbonylation Brønsted acid catalysis Acidic strength

基于格拉姆角场和PSO-CNN的滚动轴承故障诊断方法

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兵器装备工程学报 2024年第4期45卷 301-308页

作者：张国栋尹强羊柳南京理工大学机械工程学院南京210094

针对卷积神经网络的结构对滚动轴承故障诊断精度有较大影响的问题,提出一种基于格拉姆角场和粒子群优化卷积神经网络结构的故障诊断方法。采用格拉姆角场对一维轴承振动数据重构,保留原始数据信息的同时包含了时间相关性;采用粒子群优... 详细信息

针对卷积神经网络的结构对滚动轴承故障诊断精度有较大影响的问题,提出一种基于格拉姆角场和粒子群优化卷积神经网络结构的故障诊断方法。采用格拉姆角场对一维轴承振动数据重构,保留原始数据信息的同时包含了时间相关性;采用粒子群优化算法对编码后的卷积神经网络结构迭代寻优。利用西储大学的轴承数据集进行试验验证,试验结果表明,该方法可自适应生成网络结构,平均诊断精度为99%,相对于其他主流卷积神经网络结构可以获得更好的故障诊断精度。

关键词：格拉姆角场粒子群优化算法卷积神经网络滚动轴承故障诊断

欧盟行政决策权分配的“名实分离”:模式、成因与影响

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欧洲研究 2018年第4期36卷 48-65,156页

作者：杨国栋西南政法大学行政法学院

一体化的深入推动着"欧盟政府"的架构日渐成形,但欧盟层面行政决策权的行使机构仍然是一个需要明确的问题。《里斯本条约》对欧盟委员会"行使行政管理职能"和欧洲理事会"确定政治方向"的规定非但没有给出答案,反而使其更为扑朔迷离。事... 详细信息

一体化的深入推动着"欧盟政府"的架构日渐成形,但欧盟层面行政决策权的行使机构仍然是一个需要明确的问题。《里斯本条约》对欧盟委员会"行使行政管理职能"和欧洲理事会"确定政治方向"的规定非但没有给出答案,反而使其更为扑朔迷离。事实上,在欧盟层面的机构运作中已形成了欧委会和欧洲理事会以共享政策动议权为基础的行政决策模式:欧洲理事会行使着欧盟的行政决策权力,欧委会则逐渐演变为欧洲理事会的秘书处和执行机构。由于欧盟内部民主合法性和政治权威主要来自成员国,这种不同于条约文本规定的行政决策模式具有一定意义上的合理性,但其结果是行政权在欧盟和成员国两个层面都得到实质性扩大,对行政权的民主控制和监督也被弱化。此外,该模式更进一步产生了欧委会的角色异化和小成员国被边缘化却无法得到制度救济的问题,从而对欧洲一体化的深化形成障碍。从根本上而言,这种名实之间的紧张关系是成员国对一体化的承诺与对一体化深度的接受度之间形成张力的结果。

关键词：欧盟行政决策权动议权理性选择名实分离

汶川地震序列动态跟踪分析及对甘肃震情的判定

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地学前缘 2008年第6期15卷 251-259页

作者：杨国栋甘肃省地震局甘肃兰州730000

在对四川省汶川县地震序列的动态跟踪与对甘肃省震情的动态判定过程中,笔者成功地把握了甘肃震情、一定程度上把握了汶川地震序列的动态发展变化并对5月18日发生在四川省江油市的6.0级地震作出了成功预测。此次成功的地震预测实践为甘... 详细信息

在对四川省汶川县地震序列的动态跟踪与对甘肃省震情的动态判定过程中,笔者成功地把握了甘肃震情、一定程度上把握了汶川地震序列的动态发展变化并对5月18日发生在四川省江油市的6.0级地震作出了成功预测。此次成功的地震预测实践为甘肃省的抗震救灾工作提供了正确的科学依据,为减轻地震灾害和稳定被地震扰乱的社会秩序发挥了重要作用,同时也在中国地震预报的历史上写下了新的篇章。从中笔者更加深刻地感悟到,地震预报虽然是一个十分复杂、尚未被攻克的世界性难题,但对于一个特定的地区,如果预报思路和方法得当,要实现一次乃至数次成功的预报是可能的。这对地球科学家们如何认识地震预报问题有一定的意义。

关键词：龙门山断裂带汶川地震序列动态跟踪甘肃震情动态判定