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坦克炮采用交流全电控制系统的研究

兵工学报 2006年第3期27卷 549-552页

作者：臧克茂李立宇李匡成装甲兵工程学院北京100072

对应用最新交流调速技术研制出的交流全电炮控系统进行了介绍。该系统的高低向分系统用交流永磁同步电动机(PMSM)及滚珠丝杠螺旋传动代替了由动力油缸等组成的电液伺服系统。方位向分系统也采用了PMSM系统。它的性能有了很大提高;与现... 详细信息

对应用最新交流调速技术研制出的交流全电炮控系统进行了介绍。该系统的高低向分系统用交流永磁同步电动机(PMSM)及滚珠丝杠螺旋传动代替了由动力油缸等组成的电液伺服系统。方位向分系统也采用了PMSM系统。它的性能有了很大提高;与现装备相比,重量减轻40%,体积减小30%,效率提高35%;计算表明滚珠丝杠的使用期限也达到了3 240 h.可见交流全电炮控系统有很好的应用前景。

关键词：自动控制技术交流电动机调速火炮控制系统滚珠丝杠传动挠性陀螺仪

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定向井随钻监测计算

天然气工业 2005年第1期25卷 108-110页

作者：李瑜李爽中国石油西南油气田分公司重庆气矿

钻井中,需要对将要钻达的下部地层深度进行预测,特别是在定向井的钻探过程中显得尤为重要。目前的井斜角、方位能不能满足钻达目标靶区的地质需要,或者地下地质情况(地层厚度、倾向、倾角)发生变化后钻井措施的相应改变,以及需要... 详细信息

钻井中,需要对将要钻达的下部地层深度进行预测,特别是在定向井的钻探过程中显得尤为重要。目前的井斜角、方位能不能满足钻达目标靶区的地质需要,或者地下地质情况(地层厚度、倾向、倾角)发生变化后钻井措施的相应改变,以及需要调整改变的钻井参数怎样确定等,都需要经过严密的计算和分析。文章对钻井轨迹和地质情况进行了分析,从地质层位的小层入手,对构造的走向、倾向、倾角,地层的真厚、铅直厚度,钻井的方位、井斜角、实钻地层厚度等参数进行了分析,在三维空间的基础上,建立了实钻的数学模型,明确了各参数间的关系。推导出的公式适用于包括定向井在内的钻井参数计算,可以在地层钻厚预测、深度对比,钻达目标靶区的水平位移及井斜角、方位角的调整,穿越储层厚度的计算及钻井参数的调整,目标靶区是否在气水界面以内及钻达预想海拔高程的钻井参数调整等多个方面进行运用,这对下步钻井达到地质目的具有重要的指导作用。

关键词：定向钻井数学模型随钻监测方位角井斜角

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao yu-Gui Peng Peng Wu Zong-lin li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Effect of St. John＇s wort extract on depressive disorder in elderly patients with unstable angina

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World Journal of Emergency Medicine 2010年第1期1卷 41-44页

作者： Jian liu Zhao-wci Mcng li-yu li li-sha Fcng Hui Yang Department of Emergency Medicine the Second Hospital Tianjin Medical University Tianjin 300211 China

The elderly patients with coronary heart disease （CHD） are often accompanied with depression. This study aimed to assess the effect of St. John＇s wort extract （SWE） on depressive disorder in elderly patients with unstable angina pectoris. Altogether 170 patients who met the set criteria were enrolled in this prospective study. They were randomly divided into SWE group （44 patients）, Deanxit group （44）, psychotherapy group （42）, and control group （40）. The effectiveness of SWE was evaluated by reduced percentage of Hamilton depression （HAMD） scale and reduced frequency of angina pectoris attack, which were measured before and at 12 weeks after the treatment with SWE. The reduced percentages of HAMD scale were 79.5%, 56.8% and 57.1% in the SWE, Deanxit and psychotherapy groups, respectively. Compared with the control, the three groups had significant differences in the percentages （P〈0.001）. The improvement after the treatment was more significant in the SWE group than in the Deanxit or psychotherapy group （P〈0,05）. The improvement of angina pectoris evaluated by the Canadian Cardiac Society Classification was significantly better in the treatment groups （88.7%, 65.9%, 57.1%） than in the control group, and it was marked in the SWE group （P〈0.001）. Angina pectoris attack, its frequencies, durations and electrocardiographic changes were significantly improved in the treatment groups than in the control group （F=6.05, 4.58, 5.12, P〈0.01）. They are markedly improved in the SWE group （P〈0.05）. SWE can improve depressive symptoms more significantly in elderly patients with unstable angina pectoris than Deanxit or psychotherapy, proving that SWE contributes to better treatment of angina attack as well.

关键词： St. John's wort extract Depression Elderly patients Coronary heart disease Unstable angina pectoris Psychotherapy

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie li Wenbo yu Zhenyu Sun Weichen Zheng liangwei Zhang Yanling Xue Wenning liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

Dip2a regulates stress susceptibility in the basolateral amygdala

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Neural Regeneration Research 2025年第6期20卷 1735-1748页

作者： Jing li Zixuan He Weitai Chai Meng Tian Huali yu Xiaoxiao He Xiaojuan Zhu Key Laboratory of Molecular Epigenetics Ministry of Education Institute of Genetics and CytologyNortheast Normal UniversityChangchunJilin ProvinceChina

Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders.

关键词： 5-hydroxytryptamine acute restraint stress basolateral amygdala CaMKII neurons DIP2A metabolomics neurotransmitters principal component analysis stress susceptibility tryptophan

Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 164-170页

作者： WU Min CAO Kailei XIAO Weirong yu Zetai CAO Jierong DING Qingjun li Jinhui China Railway Construction Corporation Harbour and Channel Engineering Bureau Group Co. LTDZhuhai 519000China Con-struction Headquarters of Zhoushan liuheng Bridge Phase II Project Zhoushan 316000China China Railway Construction Bridge En-gineering Bureau Group Co. LTDTianjin 300000China State Key Laboratory of Silicate Material for Architecture(Wuhan University of Technology) Wuhan 430070China College of Materials Science and Engineering Wuhan Textile UniversityWuhan 430200China

The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 *** results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack *** addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate *** damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC ***,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution.

关键词： concrete external sulfate attack damage evolution situ X-ray computed tomography

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应用亚太地区TWSTFT确定同步卫星位置

电波科学学报 2008年第3期23卷 592-595页

作者：孙宏伟李玉莉西安文理学院数学系陕西西安710065

基于亚洲及太平洋地区的双向卫星时间频率比对(TWSTFT)链路和多通道时间传递调制解调器(MODEM),提出了一种确定地球同步卫星位置的方法,并估算了卫星定位的准确度。该方法原理简单,特别是这种定位建立在TWSTFT系统之上,基本上不需要额... 详细信息

基于亚洲及太平洋地区的双向卫星时间频率比对(TWSTFT)链路和多通道时间传递调制解调器(MODEM),提出了一种确定地球同步卫星位置的方法,并估算了卫星定位的准确度。该方法原理简单,特别是这种定位建立在TWSTFT系统之上,基本上不需要额外的资金投入。

关键词：时间比对 TwSTFT 卫星定位

Inter‑Skeleton Conductive Routes Tuning Multifunctional Conductive Foam for Electromagnetic Interference Shielding,Sensing and Thermal Management

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Nano-Micro Letters 2025年第3期17卷 19-36页

作者： Xufeng li Chunyan Chen Zhenyang li Peng Yi Haihan Zou Gao Deng Ming Fang Junzhe He Xin Sun Ronghai yu Jianglan Shui Caofeng Pan Xiaofang liu School of Materials Science and Engineering Beihang UniversityBeijing 100191People’s Republic of China Institute of Atomic Manufacturing Beihang UniversityBeijing 100191People’s Republic of China Tianmushan Laboratory Xixi Octagon CityYuhang DistrictHangzhou 310023People’s Republic of China Science and Technology On Electromagnetic Scattering Laboratory Beijing Institute of Environmental FeaturesBeijing 100854People’s Republic of China

Conductive polymer foam(CPF)with excellent compressibility and variable resistance has promising applications in electromagnetic interference(EMI)shielding and other integrated functions for wearable ***,its insufficient change amplitude of resistance with compressive strain generally leads to a degradation of shielding performance during ***,an innovative loading strategy of conductive materials on polymer foam is proposed to significantly increase the contact probability and contact area of conductive components under *** inter-skeleton conductive films are constructed by loading alginate-decorated magnetic liquid metal on the polymethacrylate films hanged between the foam skeleton(denoted as AMLM-PM foam).Traditional point contact between conductive skeletons under compression is upgraded to planar contact between conductive ***,the resistance change of AMLM-PM reaches four orders of magnitude under ***,the inter-skeleton conductive films can improve the mechanical strength of foam,prevent the leakage of liquid metal and increase the scattering area of EM ***-PM foam has strain-adaptive EMI shielding performance and shows compression-enhanced shielding effectiveness,solving the problem of traditional CPFs upon *** upgrade of resistance response also enables foam to achieve sensitive pressure sensing over a wide pressure range and compression-regulated Joule heating function.

关键词： Inter-skeleton conductive films Conductive polymer foam liquid metal Electromagnetic interference shielding