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Autopilot Design for a Side-Jet Missile based on MRVSS with an Adaptive Approach Law

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Autopilot Design for a Side-Jet Missile based on MRVSS with ...

第二十九届中国控制会议

作者： hugh h.t.liu University of toronto Institute for Aerospace Studies

the autopilot design of a side jet and aero-fin blending control air-to-air missile is discussed in this paper and a Model Reference Variable Sliding Structure（MRVSS）method is *** side jets are in the discontinuous on-off pulse forms which are different from the conventional continuous side *** control parameters are sought though Genetic Algorithm（GA）.Further,a novel adaptive variable-rate exponential approach law is introduced to approach the sliding surface *** proposed method is verified by simulations on a research side-jet missile model and it’s convenient to be carried out on other multi-actuator applications which is meaningful in actual engineering.

关键词： Side Jet Model Reference Variable Sliding Structure Adaptive Approach Law

Role of grain boundary character on Bi segregation-induced embrittlement in ultrahigh-purity copper

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Journal of Materials Science & technology 2023年第28期159卷 52-61页

作者： Y.X.hua K.X.Song h.t.liu J.W.Wang C.M.Zhang Y.J.Zhou B.Pang J.t.Song J.L.he h.L.Zhao School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China henan Academy of Sciences Zhengzhou 450000China henan Key Laboratory of Advanced Conductor Materials Zhengzhou 450046China Provincial and Ministerial Co-construction of Collaborative Innovation Center of Nonferrous New Materials and Advanced Processing technology Luoyang 471023China Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China College of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Bismuth(Bi),as an impurity element in copper and copper-based alloys,usually has a strong tendency of grain boundary(GB)segregation,which depends on the GB ***,the influence of such a segregation on the properties of ultrahigh-purity copper has been rarely reported and the exact structural arrangements of Bi atoms at different GBs remain largely *** this study,we investigated the influ-ence of trace amounts of Bi(50-300 wt ppm)on the ductility of an ultrahigh-purity copper(99.99999%)in the range of room temperature to 900°*** tensile results show that the addition of Bi seriously damages the ductility of the ultrahigh-purity copper at temperatures of 450-900°C,which is due to the GB segregation of *** this basis,such a segregation behavior at different types of GBs,including high and low angle GBs(hAGBs/LAGBs),and twin boundaries(tBs),via the scanning electron microscope-electron backscattered diffraction(SEM-EBSD)and aberration-corrected scanning transmission electron microscope(AC-StEM)investigations,combined with the first-principles calculations were systematically *** atomistic characterizations demonstrate an anisotropic Bi segregation,where severe enrich-ment of Bi atoms typically occurs at the hAGBs,while the absence of Bi adsorption prevails at LAGBs or *** particular,the segregated Bi at random hAGBs exhibited the directional bilayer adsorption,while the special symmetrical7 hAGB presented a unique Bi-rich cluster *** findings pro-vide a comprehensive experimental and computational understanding on the atomic-scale segregation of impurities in metallic materials.

关键词： Grain boundary character Embrittlement Bi segregation Atomic configuration Ultrahigh-purity copper

tIBEtODUS,A NEW PYCNODONt FISh FROM ChANGtU,

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古生物学报 1954年第1期 100-102页

作者： C.C.YOUNG AND h.t.liu Laboratory of Vertebrate Palaeontology,Academia Sinica.

A complete series of vomerine teeth of pycnodontoidea has been foundfrom the vicinity of Changtu(Sikang).It represents the first record of vertebrateremains in the tibetan *** PycnodontoideaFamily CyrodontidaeGenus tibetodus,new genusDiagnosis as given for the type species tibetodus gyrodoidesSpecies tibetodus gyrodoides,new ***:A vomer with the teeth nearly *** No.C.3340.

关键词： tIBEtODUS,A NEW PYCNODONt FISh FROM ChANGtU FISh

Corrosion behavior of tungsten coated SS316 as bipolar plates for PEMFC

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Corrosion behavior of tungsten coated SS316 as bipolar plate...

第九届全国氢能学术会议

作者： Y.Yang,L.J.Guo,h.t.liu 1 Xi ’an Jiaotong University,China 2 University of Miami,USA

A thin tungsten layer was coated on 316 stainless steels(SS316) by magnetron sputtering *** coated SS316 was investigated in simulated polymer electrolyte membrane fuel cell(PEMFC) environment,a solution with 0.1 M hSO and 2 ppm *** solution was kept at 80℃and was bubbled thoroughly either with hydrogen gas(to simulate PEMFC anode environment) or with pressurized air(to simulate PEMFC cathode environment) prior

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改进后的现场校准地震检波器的相位椭圆法

国外地质勘探技术 1988年第6期 43-46页

作者： h.t.liu L·PESEINICK 何旭

前言动圈式电磁地震检波器已广泛地用于野外生产,如地震勘探(telford,Geldart和Keys,1976),天然地震(Eaton,O′Neill和Murdock,1970)和地震工程研究(Abdel-一Ghaffer和Seott,z98x)。Asten(2977)己经对地震检波器转换函数和校准方法的理论分析进行过总结。在某些情况下,例如当使用地震检波器在拱坝上获得的数据,确定拱坝的振动频率和振动的特征模式时,需

关键词：电磁地震检波器电路图电路原理图椭圆法检波器响应相位角现场校准

A novel technique for evaluation on performance of Ni-Mh secondary batteries

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A novel technique for evaluation on performance of Ni-MH sec...

第九届全国氢能学术会议

作者： X.C.tang,L.X.Li,Z.Luo,X.W.Song,h.t.liu Central South University,China

＜正＞two novel conceptions of"capacity quality"（CQ） and"coefficient of capacity quality"（λ） were defined to evaluate cycling power capabilities of Ni-Mh secondary batteries in consideration of kinetic *** convenient comparison,the coefficient of capacity quality and the efficiency of charge/discharge（η） were in parallel applied to characterize cycling capabilities based on the data of BYD h-3/4AAA800mAh Ni-Mh batteries at 1C and

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Potential of eight plants for phytoextration of heavy metals from pPaddy soil

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Potential of eight plants for phytoextration of heavy metals...

International Symposium on Phytoremediation and Ecosystem health

作者： P.Zhuang h.t.liu W.S.Shu School of Life Sciences and State Key Laboratory for Bio-control Sun Yat-sen(Zhongshan) University Guangzhou 510275 China

＜正＞Phytoremediation of toxic metal-contaminated soil is one of the many current environmental challenges,and selection of hyperaccumulating plants species plays an

关键词： heavy metals phytoextration paddy soil

SYStEMAtIC CALCULAtIONS OF ENERGY LEVELS ANDRADIAtIVE RAtES OF C-LIKE IONS WIth Z=13-36 USING AN COMBINED CONFIGURAtION INtERACtION AND MANY-BODY PERtURBAtION thEORY APPROACh

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SYSTEMATIC CALCULATIONS OF ENERGY LEVELS ANDRADIATIVE RATES ...

第五届全国计算原子与分子物理学术会议

作者： J.Yan K.Wang D.F.Li h.t.liu X.Y.han B.Duan C.Y.Li J.G.Li Institute of Applied Physics and Computational Mathematics

In the present work,we report the energy levels,and electric dipole,magnetic dipole,electric quadrupole and magnetic quadrupole transition properties for 46 levels of the 2s2p,2s2p,2p,2s2p3s,2s2p3p,and 2s2p3d configurations in the C-like ions with 13≤Z≤36,in an effort to provide a complete,self-consistent and accurate *** employ a combined relativistic

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陕西鄜县及邠县中生代鱼粪化石

古生物学报 1953年第3期 157-164页

作者：刘宪亭中国科学院古脊椎动物研究室

关于我国的鱼粪化石,过去很少研究,仅尹赞动与(?)义睿两同志于1934年在贵州桐梓县青杠哨守营房之北白垩纪下部地层中,采到鱼粪类化石一枚,曾由尹教授为文详加记述,同时还记述了一枝来源不明的鱼粪,推测可能产自我国南部古生代地层中。... 详细信息

关于我国的鱼粪化石,过去很少研究,仅尹赞动与(?)义睿两同志于1934年在贵州桐梓县青杠哨守营房之北白垩纪下部地层中,采到鱼粪类化石一枚,曾由尹教授为文详加记述,同时还记述了一枝来源不明的鱼粪,推测可能产自我国南部古生代地层中。此外虽有八先后见到鱼粪化石,但多未加注意。1951年10月李德生和马继祥二同志于陕西鄜县葫芦河黑水寺侏罗纪上部地层中,及邠县水北沟三叠弛延长层地层中,采到若干鱼粪化石。此次所采到的材料,保存较佳,以产出地层时代及标本本身状况来讲,在我国化石史尤其鱼粪化石方面,颇饶意义。作者原加以记述。

关键词：螺旋瓣原大印模化石切面中生代中生界地质年代陕西