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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

基于纳秒LIBS的氢气/空气火焰混合分数测量研究

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光谱学与光谱分析 2025年第1期45卷 24-29页

作者：刘子晗刘艳韩磊单沅鲁政高强李帅瑶李博天津大学内燃机燃烧学国家重点实验室天津300072 中国科学院工程热物理研究所北京100190

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与... 详细信息

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与氧化剂混合程度的重要参数,直接影响燃烧的开始、自持以及燃烧化学反应的活跃程度。因此,对燃烧过程中的局部当量比实时在线监测,对于改善燃烧效率、控制燃烧过程具有重要意义。目前,可以实时测量氢气/空气火焰当量比的方法相对较少,激光光谱技术作为一种非侵入式的测量方法,不仅具有实时在线测量的能力,还具有快速、原位、远程分析、多元素同时在线监测等特点,在燃烧测量领域具有重要的应用潜力。采用纳秒激光诱导击穿光谱技术对氢气和空气燃烧场的燃空当量比进行测量研究。氢气和空气在管内混合后,由射流口喷出形成射流燃烧火焰场。激光通过透镜聚焦到射流燃烧场中击穿并产生等离子体,其等离子体的发射光谱由光谱仪采集,实验发现光谱中H 656 nm和O 777 nm具有很强的发射强度,且光谱强度随着当量比的变化,呈现规律性变化趋势。因此,采用H 656 nm和O 777 nm的光谱分别标示氢气和空气,并将其比值作为燃空当量比的测量参量。实验在氢气空气混合均匀的低速流场中测量了不同当量比下H 656 nm与O 777 nm的光谱强度比值,并与当量比建立标定曲线,实验发现该标定曲线对燃烧场和非燃烧场同样适用。基于标定曲线,我们研究了存在外界掺混情况下,射流燃烧场的局部燃空当量比情况。在当量比1.0,流场速度为20 m·s^(-1)的射流燃烧场中,测量了射流中心位置不同高度的燃空当量比变化情况,并在相同工况下进行了数值模拟。模拟结果与实验测量吻合较好,验证了纳秒激光诱导击穿光谱技术测量氢气/空气混合气的燃空当量比的可行性。该方法可为氢气燃烧基础研究及数值模拟提供技术支持。

关键词：激光诱导击穿光谱氢能当量比模拟

Contrast-enhanced ultrasound manifestations of synchronous combined hepatocellular-cholangiocarcinoma and hepatocellular carcinoma:A case report

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World Journal of Clinical Cases 2022年第11期10卷 3615-3623页

作者： Ling Gao Jia-Yan Huang zi-Jian lu Qiang lu Department of Ultrasound West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Ultrasound Chengdu BOE hospitalChengdu 610219Sichuan ProvinceChina Department of Pathology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Synchronous combined hepatocellular-cholangiocarcinoma(CHC)and hepatocellular carcinoma(HCC)is very rare,with few literature reports and poor clinical outcomes associated with the *** resection is the main treatment,which makes the preoperative diagnosis very ***,due to imaging manifestations overlapping with HCC,diagnosis of this type of synchronous cancer is challenging and it tends to be misdiagnosed as multiple ***,we report the contrast-enhanced ultrasound(CEUS)manifestations of a case of synchronous CHC and HCC,aiming at adding to the understanding of this *** displayed exquisite vascularity and tissue perfusion in real time with good spatial and temporal resolution and more accurately reflect tumor washin and washout times than contrast-enhanced computed tomography(CT)in this *** SUMMARY The patient was a 69-year-old female with a 20-year history of chronic hepatitis *** to months of epigastric pain and anorexia,she reffered to our hospital for *** days before hospitalization,abdominal magnetic resonance imaging performed at another hospital detected a space-occupying lesion in the *** her hospitalization,laboratory tests showed elevated alpha-fetoprotein and carbohydrate antigen 19-9 *** suspicious liver lesions located in S4 and S6,respectively,were identified in a cirrhotic background by abdominal contrast-enhanced CT(CECT).Furthermore,the lesion in S4 and S6 were detected by CEUS and assigned to CEUS LI-RADS 5 and M categories,*** patient underwent tumor radical ***-operative pathology confirmed the S4 and S6 lesions to be HCC and CHC,respectively.A newly-found suspicious liver nodule with potential malignancy was detected in liver S1 by both CEUS and CECT 7 mo after *** The CEUS characteristics of CHC and HCC are *** features in combination with clinical information could help in effective diagnosis,clinical decisio

关键词： Contrast-enhanced ultrasound Synchronous dual primary malignancies of liver Combined hepatocellular and cholangiocarcinoma Hepatocellular carcinoma Case report

Finite Size Effect in Path Integral Monte Carlo Simulations of ~4He Systems

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Communications in Theoretical Physics 2008年第10期50卷 987-989页

作者： ZHAO xing-Wen CHENG Xin-lu Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

Path integral Monte Carlo （PIMC） simulations are a powerful computational method to study interacting quantum systems at finite temperatures. In this work, PIMC has been applied to study the finite size effect of the simulated systems of ^4He. We determine the energy as a function of temperature at saturated-vapor-pressure （SVP） conditions in the temperature range of T ∈ [1.0 K,4.0 K], and the equation of state （EOS） in the grmmd state For systems consisted of 32, 64 and 128 ^4He atoms, respectively, We find that the energy at SVP is influenced significantly by the size of the simulated system in the temperature range of T ∈ [2.1 K, 3.0 K] and the larger the system is, the better results are obtained in comparison with the experimental values; while the EOS appeared to be unrelated to it.

关键词： path integral Monte Carlo simulation finite size effect helium equation of state

High sensitive and ultrafast UV photodetector based on ZrO_2 single crystals

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Science China(Physics,Mechanics & Astronomy) 2011年第8期54卷 1416-1419页

作者： xing Jie GUO ErJia lu HuiBin School of Materials Sciences and Technology China University of Geosciences Beijing 100083 China National Laboratory of Mineral Materials China University of Geosciences Beijing 100083 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

The fast-response ultraviolet (UV) photoelectric effect in ZrO2 single crystals with interdigitated electrodes has been investigated experimentally at room temperature. The photovoltage of ZrO2 single crystals exhibits a linear dependence on applied bias and light power density. The photocurrent responsivity to the UV light with a wavelength of 253.65 nm is 9.8 mA/W. For the photovoltaic pulse, a rise time of 501 ps and a full width at half maximum of 1.5 ns have been obtained, when the ZrO2 single crystal is illuminated by a 266 nm pulsed laser. These results indicate that the ZrO2 single crystal is a promising candidate for UV photodetectors.

关键词： photoelectric effect ultraviolet photodetector ZrO2 single crystals

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang Bing Zhang Lanfang Li Xiaomei Tang Jinyu Zeng Yige Song Chao Xu Kai Zhao Guoqiang Liu Youming lu Xinyan Li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Machine Learning towards Screening Solid-state Lithium Ion Conductors

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Chinese Journal of Structural Chemistry 2020年第1期39卷 8-10,1页

作者： lu Yang CHEN Xiang ZHAO Chen-zi ZHANG Qiang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Machine learning is an emerging method to discover new materials with specific *** unsupervised machine learning research is highlighted to discover new potential lithium ionic conductors by screening and clustering l... 详细信息

关键词： unsupervised machine learning first principles calculation solid state lithium ion conductors anion frameworks high ionic conductivities

Fabrication of corrosion inhibiting microcapsules functional coating and their high-efficiency corrosion resistance

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Rare Metals 2024年第2期43卷 842-848页

作者： Hao-Ran Yun lu lu Xue-Long Hao xing-Xiang Zhang School of Material Science and Engineering Tiangong UniversityTianjin300387China National Center of Analysis and Testing for Nonferrous Metals and Electronic Materials General Research Institute for Nonferrous MetalsBeijing100088China Guobiao(Beijing)Testing&Certification Co. Ltd.Beijing101407China

Benzotriazole(BTA)was loaded into calcium carbonate microsphere shell by self-assembly method and a new type of high-efficiency corrosion inhibiting microcapsules(CIMs)were fabricated,which were added and dispersed into epoxy resin coating to obtain a new corrosion resistance functional *** corrosion inhibition effect of benzotriazole on aluminum alloy matrix was verified by polarization curve *** effectiveness of the CIMs and their loading capacity on inhibitor were evaluated by scanning electron microscope,laser confocal Raman spectroscopy together with thermogravimetric analysis.

关键词： corrosion coating resistance

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四边手性蜂窝动态压溃行为的数值模拟

爆炸与冲击 2014年第2期34卷 181-187页

作者：卢子兴李康北京航空航天大学固体力学研究所北京100191

建立了四边手性蜂窝的有限元模型,采用数值模拟方法研究了四边手性蜂窝在不同冲击速度下的变形模式和能量吸收等动力学响应特性,并同普通六边形蜂窝的冲击行为进行了对比。计算得到了这2种蜂窝的变形模式图、动力响应曲线和能量吸收曲... 详细信息

建立了四边手性蜂窝的有限元模型,采用数值模拟方法研究了四边手性蜂窝在不同冲击速度下的变形模式和能量吸收等动力学响应特性,并同普通六边形蜂窝的冲击行为进行了对比。计算得到了这2种蜂窝的变形模式图、动力响应曲线和能量吸收曲线。模拟结果表明:低速冲击下,四边形手性蜂窝的变形模式为"Z"字形;高速冲击下,四边手性蜂窝的变形模式与普通蜂窝的"I"字形模式类似;在适中速度的冲击下,四边手性蜂窝表现出兼具高速冲击和低速冲击特征的一种过渡态变形模式;随着冲击速度的提高,局部变形带由固定端向冲击端移动,并且能量吸收能力也随之提高;在中、低速度的冲击下,能够观察到拉胀材料压缩时特有的"缩颈"现象。

关键词：固体力学动态压溃 ANSYS LS-DYNA 手性蜂窝变形机制能量吸收拉胀

Spatial Patterns and Drivers of Chinese Lizard Richness among Multiple Scales

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Asian Herpetological Research 2022年第2期13卷 117-124页

作者： Tao LIANG lu ZHOU Wenya DAI zi ZHANG Lei SHI College of Life Sciences Xinjiang Agricultural UniversityUrumqi 830052XinjiangChina College of Life Sciences Hainan Normal UniversityHaikou 571158HainanChina College of Forestry Nanjing Forestry UniversityNanjing 230037JiangsuChina

Species richness is one of the focuses of the preponderance of ecological *** and altitudinal gradients of species richness are two wellknown macroecological *** studies on the macroecology of species richness and its determinants are mainly focused on a single scale,although a few include multiple *** multiple scales,we can better understand the diversity gradients and the potential ***,we gathered the maps of distribution for 212 species of Chinese lizards from published studies,and to describe the overall Chinese lizard richness *** studied the relationships between the latitudinal and altitudinal patterns of species richness among Chinese lizards at the assemblage *** further tested the relationship between lizard richness and environmental factors among multiple studied scales(large scale:1.5°×1.5°,medium scale:1°×1°,and small scale:0.5°×0.5°).Regions with higher species richness occurs in in south China,and we found negative latitudinal richness *** found a low-altitude plateau pattern between species richness and altitude,and lizard richness decreased with altitude above 2500 *** richness was positively correlated with temperature and net primary productivity,but negatively correlated with actual evapotranspiration,temperature,and precipitation seasonality at all three ***,lizard species richness was positively correlated with heterogeneity only at the 1°*** on the results across multiple scales,we confirmed that the species richness patterns of Chinese lizards were driven by multiple factors,which consistent with the predictions of the ambient energy,seasonality,and productivity ***,the relationship between lizard richness and heterogeneity differed among studied scales owing to the different levels of altitude heterogeneity within grids at different scales.

关键词： altitudinal assemblage diversity environmental factors latitudinal reptile