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DISTRIBUTION OF WAVE INDUCED EXCESS MOMENTUM FLUXES OVER DEPTH AND APPLICATION TO THREE DIMENSIONAL NUMERICAL MODELING OF WAVE CURRENT INTERACTIONS

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Journal of Hydrodynamics 1999年第4期11卷 68-75页

作者： Zheng Jin hai, Yan Kai, Yan Yi xin college of Harbor, Waterway and Coastal engineering, Hohai University, Nanjing 2.0098, P.R.{2.

Using the linear wave theory, the distributions of the wave induced excess momentum fluxes over depth at the arbitrary wave angle and their asymptotic forms for deep and shallow water are developed. Results indicate that the distribution of the wave induced excess momentum fluxes over depth is non uniform and the contributions of the component below the wave trough to the total momentum fluxes become considerable in shallow water. On the basis of the Navier Stokes equations, the simplified three dimensional mathematical model is established by taking a phase average over a wavelength. It is found that there are the terms of the wave induced excess momentum fluxes varying over depth in the model, which illustrates the situation of wave current interactions and the vertical structure of current velocity are changed because of different wave induced excess momentum fluxes at various vertical location. The finite difference method is employed to solve the simplified model. Performances of the two dimensional vertically integrated equations are evaluated against available numerical and experimental results including the cases of wave set up on a plane beach, longshore current due to an oblique wave, wave induced nearshore circulation in a semi enclosed seas, and wave current interactions. All cases yield satisfactory agreements. The three dimensional mathematical model is applied to the numerical simulation of wave current interactions, and it performs well in predicting the vertical velocity structure and the plane flow field.

关键词： linear wave theory wave induced excess momentum flux distribution over depth numerical simulation wave current interactions vertical velocity structure.

新的燃烧工艺合成BaCe_(0.95)Y_(0.05)O_(3.δ)纳米粉

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中国稀土学报 2004年第6期22卷 795-799页

作者：孟波谭小耀张宝砚柳玉英杨乃涛东北大学理学院辽宁沈阳110004 山东理工大学化工学院山东淄博255049

应用基于pechini法改进的新的燃烧法合成了具有单一组成的BaCe0.95Y0.05O3.δ纳米粉体。用柠檬酸和乙二醇做金属离子螯合剂制得复合前驱物溶胶。在硝酸和氨水存在的条件下燃烧复合前驱物溶胶得到粒度小于100nm,形状均匀具有钙钛矿结构的... 详细信息

应用基于pechini法改进的新的燃烧法合成了具有单一组成的BaCe0.95Y0.05O3.δ纳米粉体。用柠檬酸和乙二醇做金属离子螯合剂制得复合前驱物溶胶。在硝酸和氨水存在的条件下燃烧复合前驱物溶胶得到粒度小于100nm,形状均匀具有钙钛矿结构的BaCe0.95Y0.05O3.δ纳米粉体。通过调节硝酸和氨水的用量可以控制粉体的粒度,柠檬酸和乙二醇的用量影响产物中碳酸盐的含量。

关键词：纳米粉钙钛矿型氧化物 BaCe0.95Y0.05O3.δ 燃烧合成稀土

Quantum nonlocality of generic family of four-qubit entangled pure states

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Chinese Physics B 2015年第7期24卷 83-87页

作者：丁东何英秋闫凤利高亭 college of Physics Science and Information engineering Hebei Normal University Department of Basic Curriculum North China Institute of Science and Technology college of Mathematics and Information Science Hebei Normal University

We directly introduce a Bell-type inequality for four-qubit systems. Using the inequality we investigate quantum nonlocality of a generic family of states ｜Gabcd〉[Phys. Rev. A 65 052.12.2.02.] and several canonical four-qubit entangled states. It has been demonstrated that the inequality is maximally violated by the so called ＂four-qubit the maximally entangled state ｜Gm〉＂ and it is also violated by four-qubit W state and a special family of states ｜Gab00〉. Moreover, a useful entanglement-nonlocality relationship for the family of states ｜Gab00〉is derived. Finally, we present a scheme of preparation of the state ｜Gm〉with linear optics and cross-Kerr nonlinearities.

关键词： quantum nonlocality Bell-type inequality quantum entanglement

Intimal hyperplasia thickness and blood flow in an axis-deviated arterial bypass

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Intimal hyperplasia thickness and blood flow in an axis-devi...

中国畜牧兽医学会2.10年学术年会——第二届中国兽医临床大会

作者： Zaipin Xu~1,Wei Zhao~1,Anqiang Sun~2.Xiaoyan Deng~2.Yubo Fan~2.Qingyu Wang~1, Dingkun Wang~1,Junbo Gao~1,Peng Luo~1,Yao Peng~1,Yuhuan Lv~1,Zhe Ma~1,Ke Wang~3.(1.Department of Veterinary medicine,college of Animal Science,Guizhou University, Guiyang 55002.,{2. 2.Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical engineering, Beihang University,Beijing 100191,{2. 3.The First Affiliation Hospital,Dalian Medical University,Dalian 116011,{2.)

Extensive work has shown that slow recirculation flow zone with low wall shear stress and high oscillatory shear index occurred in a bypassed artery is an important factor for the development of intimal hyperplasia(IH) in the distal *** substantiate our hypothesis that intentionally inducing swirling flow in a bypassed artery can suppress IH development along the floor of the host artery,we constructed an axis-deviated arterial bypass(ADAB) on canine common carotid artery in which swirling flow was created in the host artery and compared it with a conventional arterial bypass(CAB) in terms of IH development along the host artery *** flows in the two bypass models were characterized *** animal experiment showed that intimal thickness was 110.50±9.62.m in the CAB group and 60.3.±3.52.m in the ADAB group, *** blood flow simulation revealed that the flow structure in the host artery of the ADAB model was in the form of swirling flow that was very different from the vortex flow in the conventional model,which characterized with flow stagnation and low wall shear stress along the host artery *** swirling flow created by the axis-deviated bypass eliminated the stagnation flow and enhanced wall shear stress,hence suppressed IH development along the host artery ***,the present study has pointed out a new way to eliminate and/or suppress the slow recirculation flow zones in bypassed arteries.

关键词： Axis-deviated arterial bypass Bypass surgery Intimal hyperplasia Computational fluid dynamics Swirling flow Canine

EXPERIMENT STUDY ON mechanical PERFORMANCE OF HIGH-STRENGTH, LOW-HEAT AND MICRO-EXPANSION CONCRETE-FILLED STEEL TUBE

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EXPERIMENT STUDY ON MECHANICAL PERFORMANCE OF HIGH-STRENGTH,...

The International Symposium on Innovation & Sustainability of Structures in Civil engineering

作者： Shunguo Li and Zhean Lu Institute of civil engineering & architecture wuhan University of Technology wuhan 43.070 {3.

＜正＞The self-stress is one of the important mechanical performances of High-Strength,Low-heat and Micro-expansion Concrete-filled Steel Tube. In this paper, the self-stress trial of the fifteen high-strength, low-heat and micro-expansion concrete-filled steel tube （CFST） is introduced. And the generating and distributing features of pre-stress and its relation to adding quantity of expansive agent were investigated, which provides persuasive dependences for optimal design of high-strength, low-heat and micro-expansion CFST, especially for the design of added quantity of expansive agent.

关键词： High-strength low-heat and micro-expansion CFST expansive agent self-stress.

传染性支气管炎病毒RT-LAMP检测方法的建立

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中国兽医科学 2012年第11期42卷 1163-1167页

作者：范瑾谭磊仇旭升孟春春包世俊胡美容何随彬郭小琴于圣青陈书明丁铲山西农业大学动物科技学院山西太谷030801 中国农业科学院上海兽医研究所上海200241 国家家禽工程技术研究中心上海200331

为建立一种快速、灵敏、特异的检测传染性支气管炎病毒(IBV)的逆转录-环介导等温扩增方法(RT-LAMP),针对IBV毒株保守性N蛋白设计4对LAMP特异性引物,以RNA为模板,在Bst DNA聚合酶作用下恒温反应,对不同型IBV、新城疫病毒、禽流感病毒和... 详细信息

为建立一种快速、灵敏、特异的检测传染性支气管炎病毒(IBV)的逆转录-环介导等温扩增方法(RT-LAMP),针对IBV毒株保守性N蛋白设计4对LAMP特异性引物,以RNA为模板,在Bst DNA聚合酶作用下恒温反应,对不同型IBV、新城疫病毒、禽流感病毒和鸡滑液支原体进行特异性分析,并与普通RT-PCR进行灵敏性比较。结果表明RT-LAMP法在3.min就能够特异性鉴定出不同型别的IBV,且灵敏度是普通RT-PCR的107倍,反应结果可眼观判断。本研究建立的IBV RT-LAMP检测方法具备耗时短、灵敏度高、简单易行等特点,在实验室快速诊断中是一种检测IBV的有效方法。

关键词：传染性支气管炎病毒逆转录-环介导等温扩增检测

An analytical model of piezoelectric vibration energy harvesters

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An analytical model of piezoelectric vibration energy harves...

2.11年全国压电和声波理论及器件应用研讨会

作者： Yun WANG~1 Rong-qiao XU~(2.) 1 School of mechanical engineering,Hangzhou Dianzi University,Hangzhou{2.0018,china 2.Department of Civil engineering,Zhejiang University,Zijingang Campus,Hangzhou {2.0058,china

＜正＞Piezoelectric vibration energy harvesters have been paid much attention since they can scavenge mechanical energy in ambient vibration through the electro-mechanical coupling properties of piezoelectric *** cant... 详细信息

关键词： Energy harvester Piezoelectric Vibration

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三峡大学体育馆室内声学环境研究

三峡大学学报（自然科学版） 2003年第4期25卷 313-315页

作者：李运江徐波李桂媛周小庚三峡大学土木水电学院三峡大学艺术学院三峡大学建筑学2.00102.班

根据不同的使用要求,使房间具有合适的混响时间,是音质设计的重要内容之一.通过对三峡大学室内体育馆空场混响时间的测试及对满场混响时间的推算,给出了定量的音质评价.

关键词：三峡大学体育馆声学环境混响时间音质设计空场满场

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仿鸟扑翼飞行器动力学建模

系统仿真学报 2009年第15期21卷 4811-4814页

作者：魏瑞轩胡明朗郭庆孔韬西安交通大学电子与信息工程学院西安710049 空军工程大学工程学院三系西安710038

针对仿鸟扑翼飞行控制算法设计和验证需要,建立了仿鸟扑翼飞行器的动力学模型和仿真系统。在建立仿鸟扑翼飞行器柔性翼模型的基础上,基于非定常空气动力学原理,用修正的准定常气动力计算模型估算出了翅膀扑动产生的高升力;估算了平尾产... 详细信息

针对仿鸟扑翼飞行控制算法设计和验证需要,建立了仿鸟扑翼飞行器的动力学模型和仿真系统。在建立仿鸟扑翼飞行器柔性翼模型的基础上,基于非定常空气动力学原理,用修正的准定常气动力计算模型估算出了翅膀扑动产生的高升力;估算了平尾产生的控制力矩。在分析惯性力的基础上建立了扑翼飞行器的状态空间方程,进而基于Matlab语言和Simulink环境设计了微型扑翼飞行器仿真系统,并给出了相应的仿真结果。

关键词：扑翼飞行器仿鸟扑翼飞行器动力学模型 Matlab