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Physical clogging experiment of sand gravel infiltration with Yellow River water in the Yufuhe River channel of Jinan, China

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Frontiers of Earth Science 2020年第2期14卷 306-314页

作者： qingyang zheng Weiping WANG Shuai LIU Shisong QU School of Water Conservancy and Environment University of JinanJinan 250000China

To make sense of physical clogging during Yellow River water spreading in the strong leakage zone of the Yufuhe River,a laboratory sand column experiment was undertaken and the heterogeneous sand gravel with a uniformity coefficient of 25.2 from the Yufuhe River was used as an infiltration *** either the condition of raw sand or washed sand,physical clogging tests were conducted with constant hydraulic heads of 10 cm and 30 cm and inflow suspension concentrations of 200 mg/L,500 mg/L,and 1000 mg/*** fine particles in the suspension and in the raw sand were considered exogenous and endogenous particles,*** clogging was observed in the porous medium when the inflow concentrations of the exogenous particles were high,and increased hydraulic head led to serious *** result indicated that the Yufuhe River has a strong recharge capability with respect to *** analysis of particle content shows that endogenous fine particles(diameter 1–10 mm and 50–74 mm)had less mobility and generally accumulated in the sand column,whereas particles with diameter 10–50 mm had greater mobility in the sand *** the distribution of exogenous fine particles size after movement is relatively uniform in the sand *** observations indicated that the filtration effect of the aquifers have greatly improved the water quality of recharge water in the strong leakage zone of the Yufuhe River,and test data of turbidity also verified the results of the sand column experiments.

关键词： physical clogging sand column experiment exogenous particles endogenous particles

Dynamics response analysis of airborne external storage system with clearance between missile-frame

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Chinese Journal of Aeronautics 2020年第12期33卷 3278-3287页

作者： Yongfeng YANG qingyang zheng Jianjun WANG Zhongfu MA Xiangqiu LIU Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Key Laboratory of Vibration and Control of Aero-Propulsion System Ministry of Education Northeastern UniversityShenyang 110819China China Airborne Missile Academy Luoyang 471099China

Considering the aircraft and its external components are subjected to complex and variable aerodynamic loads during the working process,the missile-frame clearance system of the airborne external missile is *** random vibration characteristics of the airborne external components are analyzed by finite element *** finite element model is optimized with reference to the test results,and the effects of different clearance on the dynamic response of the missile-frame system are *** result shows that the frequency response curves of the same position and the resonant peak frequencies are consistent under different *** acceleration response at both ends of the missile is large and the amplitude near the center of mass is *** results can be used to predict reasonable missile-frame clearance and make guidance to the structural design and reliability analysis of the missile-frame system.

关键词： Airborne Dynamic response Finite element method(FEM) Missile-frame Random vibration

Flexible sensors with zero Poisson's ratio

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National Science Review 2024年第5期11卷 153-169页

作者： Xin Huang Tianzhao Bu qingyang zheng Shaoyu Liu Yangyang Li Han Fang Yuqi Qiu Bin Xie Zhouping Yin Hao Wu Department of Mechanical Engineering Flexible Electronics Research Center State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and Technology Department of Electronic Science and Technology School of Integrated CircuitsHuazhong University of Science and Technology

Flexible sensors have been developed for the perception of various stimuli. However, complex deformation,usually resulting from forces or strains from multi-axes, can be challenging to measure due to the lack of independent perception of multiaxial stimuli. Herein, flexible sensors based on the metamaterial membrane with zero Poisson's ratio(ZPR) are proposed to achieve independent detection of biaxial stimuli. By deliberately designing the geometric dimensions and arrangement parameters of elements, the Poisson's ratio of an elastomer membrane can be modulated from negative to positive, and the ZPR membrane can maintain a constant transverse dimension under longitudinal stimuli. Due to the accurate monitoring of grasping force by ZPR sensors that are insensitive to curvatures of contact surfaces, rigid robotic manipulators can be guided to safely grasp deformable objects. Meanwhile, the ZPR sensor can also precisely distinguish different states of manipulators. When ZPR sensors are attached to a thermal-actuation soft robot, they can accurately detect the moving distance and direction. This work presents a new strategy for independent biaxial stimuli perception through the design of mechanical metamaterials, and may inspire the future development of advanced flexible sensors for healthcare, human–machine interfaces and robotic tactile sensing.

关键词： zero Poisson's ratio metamaterials independent perception of multiaxial stimuli flexible sensor

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IEEE 1394总线技术与应用

现代电子技术 2002年第3期25卷 33-36页

作者：郑青阳许化龙第二炮兵工程学院西安710025

IEEE1394是一种高带宽、灵活方便的串行总线 ,已广泛应用于数码影像设备。介绍了其发展背景和主要技术规范 ,详细分析了其技术特点和应用范围。

关键词： IEEE 1394 总线技术串行总线数据传输

具有不停电换表功能的单相电能表接插件的研制

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农村电气化 2019年第4期 73-75页

作者：刘洪儒郑庆阳阮召安国网平阳县供电有限责任公司浙江平阳325401

随着人们对美好生活向往的不断提高,对供电可靠性的要求也逐步提高。目前单相电能表换表数量巨大,电能表更换造成了用户的长时间停电,同时造成了大量未换表用户停电,严重影响供电服务质量,成为用户不满意的风险点之一。本文介绍了单相... 详细信息

随着人们对美好生活向往的不断提高,对供电可靠性的要求也逐步提高。目前单相电能表换表数量巨大,电能表更换造成了用户的长时间停电,同时造成了大量未换表用户停电,严重影响供电服务质量,成为用户不满意的风险点之一。本文介绍了单相电能表接插件实现不停电换表及短路电量计量的原理,提出了接插件、短路构件等部件的技术要求,解决了换表引起的用户末端停电问题,提高了供电可靠性。

关键词：接插件不停电换表短路电量计量

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浅谈正确使用冷却液与发动机冷却系统的影响

汽车实用技术 2018年第21期44卷 281-282页

作者：翁旭委郑清扬杨晓冬缙云县永武缙机动车检测有限公司浙江丽水321400

文章主要介绍锡柴CA6DL2-35E3博世电控高压共轨柴油发动机载货汽车。由于冷却系统加水造成发动机高温,缸套早期穴蚀漏水现象,通过更换维修加注锡柴R牌冷却液后该车恢复良好的工作工况,延长了发动机的使用寿命,给用户创造了更多的实用性... 详细信息

文章主要介绍锡柴CA6DL2-35E3博世电控高压共轨柴油发动机载货汽车。由于冷却系统加水造成发动机高温,缸套早期穴蚀漏水现象,通过更换维修加注锡柴R牌冷却液后该车恢复良好的工作工况,延长了发动机的使用寿命,给用户创造了更多的实用性和经济性。

关键词：发动机高温腐蚀冷却系统冷却液

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短柄乌头中二萜生物碱类成分及心脏毒性研究

中国现代应用药学 2024年第18期41卷 2572-2579页

作者：陶培刘丛改红花拉巴次仁陈佳佳郑清洋泽翁拥忠王毓杰成都中医药大学成都611137 重庆市永川区中医院重庆402160 林芝市藏医院西藏林芝860000 林芝市工布江达县江达乡卫生院西藏林芝860000

目的研究短柄乌头块根中二萜生物碱的结构及心脏毒性。方法采用硅胶柱色谱及波谱法分离鉴定化合物的结构;采用大鼠模型比较不同化合物的心脏毒性。结果从短柄乌头中分离得到12个二萜生物碱,分别鉴定为secokaraconitine(1)、oxonitine... 详细信息

目的研究短柄乌头块根中二萜生物碱的结构及心脏毒性。方法采用硅胶柱色谱及波谱法分离鉴定化合物的结构;采用大鼠模型比较不同化合物的心脏毒性。结果从短柄乌头中分离得到12个二萜生物碱,分别鉴定为secokaraconitine(1)、oxonitine(2)、查斯曼宁(3)、草乌甲素(4)、尼奥林(5)、去氧乌头碱(6)、乌头碱(7)、印乌碱(8)、滇乌碱(9)、塔拉萨敏(10)、苯甲酰乌头原碱(11)、乌头原碱(12)。通过整体动物心脏毒性试验证实:1-OH、3-OH、8-COCH_(3)、14-苯甲酰基能够增强乌头烷类化合物的心脏毒性,6-OCH_(3)、N-CHO、N=C能够降低该类化合物的心脏毒性。结论通过整体动物试验明确了不同取代基对乌头烷类化合物心脏毒性的影响。

关键词：乌头属短柄乌头二萜生物碱心脏毒性 secokaraconitine oxonitine

热带香蕉园地土壤呼吸变化特征及其与环境因子的关系

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海南师范大学学报（自然科学版） 2019年第1期32卷 99-107页

作者：郑庆扬赵从举陈丽艳王城城海南师范大学地理与环境科学学院海南海口571158

香蕉园是海南重要的农田生态系统类型。为了探明香蕉园地土壤呼吸的变化特征及其与环境因子之间的关系,2016年11月—2017年10月运用LI-8100A土壤呼吸测量系统对海南澄迈香蕉园地行间与株间的土壤呼吸进行系统监测分析。结果表明:香蕉园... 详细信息

香蕉园是海南重要的农田生态系统类型。为了探明香蕉园地土壤呼吸的变化特征及其与环境因子之间的关系,2016年11月—2017年10月运用LI-8100A土壤呼吸测量系统对海南澄迈香蕉园地行间与株间的土壤呼吸进行系统监测分析。结果表明:香蕉园地行间、株间土壤CO_2通量日变化均呈现出昼高夜低的特点,但株间土壤CO_2通量日最大值出现时间较行间要晚1.5 h左右,株间土壤CO_2通量高于行间,二者之间存在显著差异(p 0.05);月尺度土壤温度对行间土壤CO_2通量变化有显著影响(p <0.05),香蕉植株生长对株间土壤CO_2通量变化影响显著(p <0.01),而其他因子的影响均未达到显著水平。研究结果丰富了热带农田土壤CO_2通量研究资料,为热带农田土壤碳源–汇的准确评估提供了数据支持。

关键词：土壤呼吸株间与行间环境因子香蕉园地

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电工膜用高纯聚丙烯树脂的现状

河南化工 2021年第5期38卷 18-21页

作者：徐辉张丕生陈豹郑庆阳中国石化中原石油化工有限责任公司河南濮阳457000

综述了电工膜用高纯聚丙烯树脂的主要性能特点,以及近年来国内各企业的生产现状。分析了目前电工膜用聚丙烯树脂的性能研究及存在问题。介绍了开发生产该产品的重要性,争取早日实现该材料的国产化替代,对产业自主的发展具有重大意义。

关键词：电工膜高纯聚丙烯国产化