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三峡工程 1

升船机 1

变径毛细管节流器 1

变隙滑阀节流器 1

变隙薄板节流器 1

天线对；第五代移动通信技术（5G）；Sub-6 GHz；极化正交；智能终端；智能手机；零净空；全金属外壳；多输入多输出（MIMO） 1

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节流变量指数 1

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Copper and zinc interaction on water clearance and tissue metal distribution in the freshwater mussel

Tianxiang XIA, Xuehua LIU

《环境科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 236-242 doi: 10.1007/s11783-010-0218-8

摘要： Copper and zinc interaction on clearance from water and distribution in different tissues was investigated for the freshwater mussel, , under laboratory conditions. Clearance rate of Cu or Zn from water was highly dependent on exposure concentration. Interaction effect was most evident at 300 μg·L Cu exposure and depressed the Zn clearance rate significantly ( <0.05). However, the presence of 100 μg·L and 300 μg·L Zn hardly affected the Cu clearance rate. The 300 μg·L Cu presence enhanced Cu accumulation in each tissue most significantly ( <0.01), but caused Zn content to decrease in the gills by 62% ( <0.05), viscera by 49% ( <0.05) and foot by 31% ( <0.05), and increase in the mantle by 97% ( <0.05) and the muscles by 243% ( <0.05) for different Zn exposure treatments. The response of metal accumulation in various tissues of the test mussels indicated that Zn transferred from the gills, viscera and foot to the mantle and muscles might be one of the important characteristics of the Zn regulatory mechanism by leading to a narrow range of Zn concentration in the different tissues.

关键词： interaction     mussel     copper     zinc     clearance     distribution    

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Fluid damping clearance in a control valve of injector

ZHANG Jianming, ZHANG Weigang, YANG Bing, WANG Yawei

《机械工程前沿（英文）》 2007年 第2卷 第4期   页码 439-441 doi: 10.1007/s11465-007-0075-x

摘要： A force model of a control valve of injector is set up, and the changes of the fluid damping clearance are investigated on the basis of the results of the computational fluid dynamics (CFD) and the experiments of control valve of injector. Results indicate that a damping clearance of 0.02–0.03 mm between the poppet and the valve guide is the most sufficient to dampen any excessive control valve poppet bouncing.

关键词： control     computational     bouncing     CFD     excessive control    

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Measurement and analysis of tip clearance unsteady flow spectrum in axial-flow fan rotor

LIU Bo, HOU Weimin, MA Changyou, WANG Yangang, ZHOU Qiang

《能源前沿（英文）》 2008年 第2卷 第4期   页码 448-452 doi: 10.1007/s11708-008-0088-0

摘要： The dynamic pressure measurement device and test technology are described in this study. The tip clearance unsteady flow development from the inlet to the outlet of an axial-flow rotor was revealed by analyzing pressure frequency spectrum acquired from measuring the unsteady pressure field of the tip endwall. The experiment provides test basis for thoroughly understanding the tip clearance unsteady flow and building interaction models of tip clearance flow and main flow.

关键词： development     endwall     unsteady pressure     pressure measurement     experiment    

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节流性能优异的新型液体静压支承节流器

孟心斋,孟昭焱

《中国工程科学》 2005年 第7卷 第3期   页码 49-52

摘要：

传统的液体静压支承节流器存在严重缺陷，性能不佳，不能消除支承间隙随外加载荷增加而剧减的缺点，严重影响其实际应用。新型节流器节流变量指数b≥3，能够保持节流器进油与油囊排油速度接近一致。此外，当有外加载荷作用于支承时，油囊压力会升高，迫使节流变量产生附加增量，从而弥补了因油囊压力升高而减少供油量与油囊增加的排油量。因此，新型节流器能够保证在有外加载荷作用时支承间隙变化很小或近于不变。新型节流器节流性能优良，结构简单，成本低廉，体积较小，具有实用价值。

关键词： 变隙滑阀节流器     变隙薄板节流器     变径毛细管节流器     节流变量指数    

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Parasitic rotation evaluation and avoidance of 3-UPU parallel mechanism

Haibo QU, Yuefa FANG, Sheng GUO

《机械工程前沿（英文）》 2012年 第7卷 第2期   页码 210-218 doi: 10.1007/s11465-012-0317-4

摘要：

Based on the prototype of 3-UPU (universal-prismatic-universal joint) parallel mechanism proposed by Tsai [ ], the parasitic rotation evaluation is performed and calculated the bound of instability of SNU Seoul National University 3-UPU parallel mechanism. Through analysis of the terminal constraint system of the 3-UPU parallel mechanism, the equation about the parasitic rotation and limited clearance is presented. Then the norm of possible parasitic rotation is employed to evaluate the mechanism stability with limited clearance. The higher this number the worst is the pose, the lower it is the best it is. And the contour atlas of parasitic rotation is obtained, which can be used for further analysis and design. With the practice experiment result of SUN 3-UPU parallel mechanism, we find it’s bound of instability, which indicates there will appear the parasitic rotation when the number exceeds the bound. Finally, the method for avoidance of possible parasitic motions is presented by adding redundantly actuated limbs.

关键词： parallel mechanism     3-UPU (universal-prismatic-universal joint)     parasitic motions     limited clearance     redundantly actuated limbs    

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三峡升船机齿条及螺母柱间隙灌浆工艺试验

詹剑霞,李纪虎

《中国工程科学》 2013年 第15卷 第9期   页码 45-49

摘要：

为了选择出合适的灌浆材料和灌浆工艺并模拟升船机齿条、螺母柱间隙灌浆的实际情况，分别进行了灌浆工艺试验与原型灌浆试验。灌浆工艺试验对比了3种国产灌浆材料和德国PAGEL灌浆材料，试验结果表明德国PAGEL灌浆材料物理性能指标和力学性能指标优于国产灌浆材料。在原型灌浆试验中，对灌浆设备选型、搅拌时间、模板密封、灌浆方式、灌浆流速参数控制等方面进行了试验研究，优选出适用于三峡升船机齿条、螺母柱接缝灌浆的材料和合适的灌浆工艺。以上试验效果明显，解决了灌浆密封难度大、易堵管等施工难题。

关键词： 齿条     螺母柱     灌浆     升船机     三峡工程    

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适用于全金属外壳5G多输入多输出智能终端的零净空正交同频天线对 Correspondence

常乐1,贺文宝1,陈小民2,檀笑雪1,陈娟1,康凯3,杨阳4

《信息与电子工程前沿（英文）》 2022年 第23卷 第10期   页码 1562-1567 doi: 10.1631/FITEE.2200119

摘要：

本文首次提出零净空天线对，可适用于全金属外壳第五代移动通信技术（5G）多输入多输出（MIMO）智能终端。该天线对是金属边框上的T形槽结构，可以看作由两个对称的口对口开口槽构成。该结构存在两种工作于半波模式的极化正交特征模：对于同相电流环模式，两个开口槽相位相反，可以通过在缝隙处建立电位差来激励；对于槽模式，两个开口槽相位相同，可由一个对称馈电网络来激励。得益于T形槽位于侧边边框，不需要天线净空，非常适用于现代全面屏智能终端，终端后盖可采用金属材质，适用于全金属外壳终端。本文加工了一个Sub-6 GHz的四天线阵列来验证其可行性。在3.4–3.6 GHz，两对天线对的隔离性均优于16.9 dB，任意两个天线之间的包络相关系数（ECC）均小于0.13，两种模式的总效率范围分别为43.5%–61.9%和40.5%–53.5%。

关键词： 天线对；第五代移动通信技术（5G）；Sub-6 GHz；极化正交；智能终端；智能手机；零净空；全金属外壳；多输入多输出（MIMO）    

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标题 作者 时间 类型 操作

Copper and zinc interaction on water clearance and tissue metal distribution in the freshwater mussel

Tianxiang XIA, Xuehua LIU

期刊论文

Fluid damping clearance in a control valve of injector

ZHANG Jianming, ZHANG Weigang, YANG Bing, WANG Yawei

期刊论文

Measurement and analysis of tip clearance unsteady flow spectrum in axial-flow fan rotor

LIU Bo, HOU Weimin, MA Changyou, WANG Yangang, ZHOU Qiang

期刊论文

节流性能优异的新型液体静压支承节流器

孟心斋,孟昭焱

期刊论文

Parasitic rotation evaluation and avoidance of 3-UPU parallel mechanism

Haibo QU, Yuefa FANG, Sheng GUO

期刊论文

三峡升船机齿条及螺母柱间隙灌浆工艺试验

詹剑霞,李纪虎

期刊论文

适用于全金属外壳5G多输入多输出智能终端的零净空正交同频天线对

常乐1,贺文宝1,陈小民2,檀笑雪1,陈娟1,康凯3,杨阳4

期刊论文