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(Mg_(0.95)Ca_(0.05))TiO_3晶体的激光加热基座法生长及其性质测定

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功能材料 2003年第2期34卷 158-159页

作者：蒋毅坚 r.guo A.S.Bhalla 北京工业大学国家产学研激光技术中心北京100022 宾夕法尼亚州立大学材料研究实验室

采用激光加热基座法(LHPG)生长出了共晶系(Mg0.95Ca0.05)TiO3晶体。通过粉末X射线衍射分析了所生长晶体的晶相,采用扫描电镜和显微拉曼光谱技术研究了所生长晶体的微观结构。(Mg0.95Ca0.05)TiO3晶体由CaTiO3和Mg-TiO3两种晶体复合而成... 详细信息

采用激光加热基座法(LHPG)生长出了共晶系(Mg0.95Ca0.05)TiO3晶体。通过粉末X射线衍射分析了所生长晶体的晶相,采用扫描电镜和显微拉曼光谱技术研究了所生长晶体的微观结构。(Mg0.95Ca0.05)TiO3晶体由CaTiO3和Mg-TiO3两种晶体复合而成。介电测量结果表明:(Mg0.95Ca0.05)TiO3晶体沿生长方向具有较大的介电常数和较小的共振频率温度系数。

关键词：激光加热基座法共晶介电性质晶体生长粉末X射线衍射微波介电材料

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PSKNN铁电单晶及其激光法生长

中国激光 2000年第9期27卷 842-846页

作者：蒋毅坚 r.guo A.S.Bhalla 北京工业大学国家产学研激光技术中心北京100022 宾夕法尼亚州立大学材料研究实验室

采用改进的激光加热基座法 (LHPG)生长出了位于准同形相界附近的含有 Pb元素的钨青铜结构的铁电晶体 (1- x) Pb2 KNb5O15- x Sr2 Na Nb5O15(PSKNN)。通过调节激光功率和陶瓷源棒中 Pb O的含量 ,有效地控制和补偿了晶体生长过程中 Pb O... 详细信息

采用改进的激光加热基座法 (LHPG)生长出了位于准同形相界附近的含有 Pb元素的钨青铜结构的铁电晶体 (1- x) Pb2 KNb5O15- x Sr2 Na Nb5O15(PSKNN)。通过调节激光功率和陶瓷源棒中 Pb O的含量 ,有效地控制和补偿了晶体生长过程中 Pb O的挥发。通过选择适当的籽晶 ,可以得到沿 [0 0 1],[10 0 ]和 [110 ]方向生长的 PSKNN晶体。研究了所生长晶体的铁电、介电和压电性质 ,并对其准同形相界进行了初步的讨论。

关键词： PSKNN 铁电单晶激光加热基座生长

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Ta_2O_5单晶的激光法生长

应用激光 2002年第2期22卷 244-246页

作者：蒋毅坚 r.guo A.S.Bhalla 北京工业大学国家产学研激光技术中心 Materials research Laboratory The Pennsylvania State UniversityPA 16802USA

采用激光加热基座生长法(LHPG)生长出Ta_2O_5单晶,测量了所生长晶体的介电系数和介电损耗随晶格方向的关系。Ta_2O_5晶体表现出很强的介电各向异性,并且其介电系数的平均值比 Ta_2O_5陶瓷的大许多。Ta_2O_5单晶的成功生长证明了LHPG技... 详细信息

采用激光加热基座生长法(LHPG)生长出Ta_2O_5单晶,测量了所生长晶体的介电系数和介电损耗随晶格方向的关系。Ta_2O_5晶体表现出很强的介电各向异性,并且其介电系数的平均值比 Ta_2O_5陶瓷的大许多。Ta_2O_5单晶的成功生长证明了LHPG技术在生长高熔点晶体方面所具有的独特能力,同时也表明它作为一种特殊的激光材料加工技术在材料科学与工程中将发挥重要作用。

关键词：激光加热基座生长法 Ta205单晶介电性质介电损耗晶格方向 LHPG技术激光材料加工技术介电材料五氧化二钽

Molecular Basis of KAT2A Selecting Acyl-CoA Cofactors for Histone Modifications

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research 2023年第2期2023卷 577-581页

作者： Sha Li Nan Li Jie He runxin Zhou Zhimin Lu Yizhi Jane Tao Yusong r.guo Yugang Wang Department of Biochemistry and Molecular Biology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China Department of Neurosurgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Zhejiang University School of Medicine HangzhouZhejiang 310029China Department of Bioscience Rice UniversityHoustonTX 77005USA Cell Architecture research Center Huazhong University of Science and TechnologyWuhanHubei 430030China

Emerging discoveries about undocumented acyltransferase activities of known histone acetyltransferases(HATs)advance our understandings in the regulation of histone ***,the molecular basis of HATs selecting acyl coenzyme A(acyl-CoA)substrates for histone modification is less *** here report that lysine acetyltransferase 2A(KAT2A)as an illustrative instance of HATs can selectively utilize acetyl-CoA,propionyl-CoA,butyryl-CoA,and succinyl-CoA to directly deposit 18 histone acylation hallmarks in *** analyzing the co-crystal structures of the catalytic domain of KAT2A in complex with acetyl-CoA,propionyl-CoA,butyryl-CoA,malonyl-CoA,succinyl-CoA,and glutaryl-CoA,we conclude that the alternative substrate-binding pocket of KAT2A and the length and electrostatic features of the acyl chain cooperatively determine the selection of the acyl-CoA substrates by *** study reveals the molecular basis underlying the pluripotency of HATs that selectively install acylation hallmarks in nucleosomes,which might serve as instrumental mechanism to precisely regulate histone acylation profiles in cells.

关键词： utilize selecting electrostatic

三维高分辨黑血晚期钆增强成像改善心房瘢痕评估

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国际医学放射学杂志 2023年第4期 484-485页

作者： D.Y.Si Y.F.Wu J J.Xiao X.H.Qin r.guo B.W.Liu 秦桂姣

摘要射频消融(rFA)是一种广泛应用于房颤的治疗方法，可降低心律失常的风险。心房瘢痕的详细可视化和量化有可能改善术前决策和术后预后。传统的亮血晚期钆增强

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Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN Jie guo ruiLong guo HengYu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Applied Physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

Physicochemical principles of hydrogen metallurgy in blast furnace

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Journal of Iron and Steel research International 2024年第1期31卷 46-63页

作者： Han-jie guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China

Based on the stoichiometric method and the free energy minimization method,an ideal model for the reduction of iron oxides by carbon and hydrogen under blast furnace conditions was established,and the reduction efficiency and theoretical energy consumption of the all-carbon blast furnace and the hydrogen-rich blast furnace were *** results show that after the reduction reaction is completed at the bottom of the blast furnace,the gas produced by reduction at 1600℃still has a certain excessive reduction capacity,which is due to the hydrogen brought in by the hydrogen-rich blast as well as the excess carbon monoxide generated by the reaction of the coke and the oxygen brought in by the *** the process of the gas with excessive reduction capacity rising from the bottom of the blast furnace and gas reduction process,the excessive reduction capacity of the gas gradually decreases with the increase in the dydrogen content in the *** the all-carbon blast furnace,the excess gas reduction capacity is the strongest,and the total energy consumption per ton of iron reduction is the *** shows that,for the current operation mode of the blast furnace,adding hydrogen in the blast furnace cannot reduce the consumption of carbon required for reduction per ton of iron,but rather increases the consumption of carbon.

关键词： Hydrogen metallurgy Excess gas reduction capacity Theoretical energy consumption Hydrogen-rich blast furnace Thermodynamic model Gibbs minimum free energy method

Control Strategies for Digital Twin Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 170-180页

作者： guo-Ping Liu IEEE the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

With the continuous breakthrough in information technology and its integration into practical applications, industrial digital twins are expected to accelerate their development in the near future. This paper studies various control strategies for digital twin systems from the viewpoint of practical *** make full use of advantages of digital twins for control systems, an architecture of digital twin control systems, adaptive model tracking scheme, performance prediction scheme, performance retention scheme, and fault tolerant control scheme are proposed. Those schemes are detailed to deal with different issues on model tracking, performance prediction, performance retention, and fault tolerant control of digital twin systems. Also, the stability of digital twin control systems is analysed. The proposed schemes for digital twin control systems are illustrated by examples.

关键词： Digital twin control systems fault tolerant control model tracking performance prediction performance retention

Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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China Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG guo-xing XIA Xin-lu guo Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis