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风浪耦合作用下5MW阶梯立柱式海上风机动态响应研究

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中国电机工程学报 2022年第12期42卷 4477-4486页

作者：黄承庚陈莉张欢陈达河海大学港口海岸与近海工程学院江苏省南京市210098

以NERL 5MW风力机为研究对象,基于阶梯立柱式平台建立整体漂浮式风机,综合运用FAST和AQWA软件,通过叶素动量理论和势流理论并整合有限元方法,实现风浪耦合作用下风机动态响应的求解。数值模拟结果表明:频域分析中,纵荡、垂荡和纵摇的幅... 详细信息

以NERL 5MW风力机为研究对象,基于阶梯立柱式平台建立整体漂浮式风机,综合运用FAST和AQWA软件,通过叶素动量理论和势流理论并整合有限元方法,实现风浪耦合作用下风机动态响应的求解。数值模拟结果表明:频域分析中,纵荡、垂荡和纵摇的幅值响应算子最大值对应波浪频率不超过0.2rad/s;自由衰减分析中,阶梯立柱式海上风机在三自由度上(纵荡、垂荡和纵摇)的固有频率分别为0.0419rad/s、0.2067rad/s和0.1496rad/s,很好地规避了南海典型波浪频率;时域分析中,正常工作时,阶梯立柱式海上风机较好地保持了立柱式海上风机垂荡激励小的特点,且在纵荡和纵摇上的位移也能保持在合理的范围内;系泊缆断裂后,阶梯立柱式海上风机能够实现平稳停机,表现出对南海海域中等水深环境很强的适应性。

关键词：阶梯立柱式平台叶素动量理论势流理论三自由度自由衰减分析频域分析时域分析

Overview of Rubik's Cube and Reflections on Its Application in Mechanism

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 9-20页

作者： da.Xing Zeng Ming Li Juan-Juan Wang Yu-Lei Hou Wen-Juan Lu Zhen Huang School of Mechanical Engineering Yanshan University

Rubik’s Cube is a widely popular mechanical puzzle that has attracted attention around the world because of its unique characteristics. As a classic brain-training toy well known to the public, Rubik’s Cube was used for scientific research and technology development by many scholars. This paper provides a basic understanding of the Rubik’s Cube and shows its mechanical art from the aspects of origin and development, characteristics, research status and especially its mechanical engineering design, as well as making a vision for the application in mechanism. First, the invention and origin of Rubik’s Cube are presented, and then the special characteristics of the cube itself are *** that, the present researches of Rubik’s Cube are reviewed in various disciplines at home and abroad, including the researches of Rubik’s Cube scientific metaphors, reduction algorithms, characteristic applications, and mechanism issues. Finally, the applications and prospects of Rubik’s Cube in the field of mechanism are discussed.

关键词： Rubik's Cube Scientific research Mechanical art Application and prospects

Measuring Zak phase in room-temperature atoms

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Light(Science & Applications) 2022年第10期11卷 2530-2539页

作者： Ruosong Mao Xingqi Xu Jiefei Wang Chenran Xu Gewei Qian Han Cai Shi-Yao Zhu da.Wei Wang Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical Instrumentationand Zhejiang Province Key Laboratory of Quantum Technology and DeviceSchool of PhysicsZhejiang UniversityHangzhou 310027China College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027China Hefei National Laboratory Hefei 230088China CAS Center of Excellence in Topological Quantum Computation 100190 BeijingChina

Cold atoms provide a flexible platform for synthesizing and characterizing topological matter,where geometric phases play a central ***,cold atoms are intrinsically prone to thermal noise,which can overwhelm the topological response and hamper promised *** the other hand,geometric phases also determine the energy spectra of particles subjected to a static force,based on the polarization relation between Wannier-Stark ladders and geometric Zak *** exploiting this relation,we develop a method to extract geometric phases from energy spectra of room-temperature superradiance lattices,which are momentum-space lattices of timed Dicke *** such momentum-space lattices the thermal motion of atoms,instead of being a source of noise,provides effective forces which lead to spectroscopic signatures of the Zak *** measure Zak phases directly from the anti-crossings between Wannier-Stark ladders in the Doppler-broadened absorption spectra of superradiance *** approach paves the way of measuring topological invariants and developing their applications in room-temperature atoms.

关键词： topological momentum invariants

Analysis of Potential Energy Surface for Butanone Isomerization

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Chinese Journal of Chemical Physics 2013年第5期26卷 519-525,I0003页

作者： Xue Yang Bing Yan Hai-feng Xu Rui-han Zhu Mei-xia Zhang da.jun Ding Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China College of Science Jilin Institute of Chemical Technology Jilin 132022 China

为 butanone 异构化的势能表面被密度功能理论计算调查了。六条主要反应小径用内在的反应坐标方法被证实，并且相应异构化产品是 1buten2ol， 2buten2ol， butanal 或 1buten1ol，甲基 1propenyl 醚，甲基 allyl 醚，和乙醇乙烯基醚分... 详细信息

为 butanone 异构化的势能表面被密度功能理论计算调查了。六条主要反应小径用内在的反应坐标方法被证实，并且相应异构化产品是 1buten2ol， 2buten2ol， butanal 或 1buten1ol，甲基 1propenyl 醚，甲基 allyl 醚，和乙醇乙烯基醚分别地。在他们之中，通过丁烯氧化物有三条小径，显示丁烯氧化物是在 butanone 异构化期间的一个重要中间的产品。反应物和它的产品的计算垂直电离精力在与可得到的试验性的价值的一个好协议。从为转变状态的相对精力和 highenergy 障碍的数字的考虑，我们推断反应小径 butanone1buten2ol 2buten2ol 是最有竞争力的。获得的结果为酉同类分子的异构化上的未来研究是增进知识的。

关键词：异构化过程势能面丁酮乙基乙烯基醚内禀反应坐标法丁烯-1 密度泛函理论反应途径

Design,Optimization and Numerical Modelling of A Novel Floating Pendulum Wave Energy Converter with Tide Ada.tation

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China Ocean Engineering 2017年第5期31卷 578-588页

作者： YANG Jing ZHANG da.hai CHEN Ying LIANG Hui TAN Ming LI Wei MA Xian-dong Ocean College Zhejiang University The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Engineering Department Lancaster University

A novel floating pendulum wave energy converter （WEC） with the ability of tide ada.tation is designed and presented in this paper. Aiming to a high efficiency, the buoy＇s hydrodynamic shape is optimized by enumeration and comparison. Furthermore, in order to keep the buoy＇s well-designed leading edge always facing the incoming wave straightly, a novel transmission mechanism is then adopted, which is called the tida. ada.tation mechanism in this paper. Time domain numerical models of a floating pendulum WEC with or without tide ada.tation mechanism are built to compare their performance on various water levels. When comparing these two WECs in terms of their average output based on the linear passive control strategy, the output power of WEC with the tide ada.tation mechanism is much steadier with the change of the water level and always larger than that without the tide ada.tation mechanism.

关键词： wave energy simulation model analysis tide ada.tation

Effect of laser shock peening on combined low- and high-cycle fatigue life of casting and forging turbine blades

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Journal of Iron and Steel Research(International) 2018年第1期25卷 108-119页

作者： Cao Chen Xiao-yong Zhang Xiao-jun Yan Jun Ren da.wei Huang Ming-jing Qi School of Energy and Power Engineering BeihangUniversity Beijing 100191 China Collaborative Innovation Center of Advanced Aero-Engine Beijing 100191 China National Key Laboratory of Science and Technologyon Aero-Engine Aero-Thermodynamics Beijing 100191China Beijing Key Laboratory of Aero-Engine Structureand Strength Beijing 100191 China

Laser shock peening （LSP） is a novel effective surface treatment method to improve the fatigue performance of turbine blades. To study the effect of LSP on combined low- and high-cycle fatigue （CCF） life of turbine blades, the CCF tests were conducted at elevated temperatures on two types of full-scale turbine blades, which were made of K403 by casting and GH4133B by forging. Probabilistic analysis was conducted to find out the effect of LSP on fatigue life of those two kinds of blades. The results indicated that LSP extended the CCF life of both casting blades and forging blades obviously, and the effect of LSP on casting blades was more evident; besides, a threshold vibration stress existed for both casting blades and forging blades, and the CCF life tended to be extended by LSP only when the vibration stress was below the threshold vibra- tion stress. Further study of fractography was also conducted, indicating that due to the presence of compressive residual stress and refined grains induced by LSP, the crack initiation sources in LSP blades were obviously less, and the life of LSP blades was also longer; since the compressive residual stress was released by plastic deformation, LSP had no effect or adverse effect on CCF life of blade when the vibration stress of blade was above the threshold vibration stress.

关键词： Laser shock peening Combined low-and high-cycle fatigue life (CCF) Full-scale turbine blade S-N curve -Threshold vibration stress

基于非稳态和稳态Wells-Riley模型的机械通风控制策略对于疾病空气传播和建筑能耗的影响

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Journal of Central South University 2022年第7期29卷 2415-2430页

作者：沙浩瀚张鑫戚大海 Department of Civil and Building Engineering Universitéde SherbrookeSherbrooke J1K 2R1Canada

通风是一种有效提高室内空气质量和降低疾病通过空气传播的方法。足量的通风可以降低疾病传播风险,但过量的通风会提高建筑能耗。通风策略需要兼顾这两方面。Wells-Riley(WR)模型常用于预测感染风险和控制通风。但很少有研究对比非稳态... 详细信息

通风是一种有效提高室内空气质量和降低疾病通过空气传播的方法。足量的通风可以降低疾病传播风险,但过量的通风会提高建筑能耗。通风策略需要兼顾这两方面。Wells-Riley(WR)模型常用于预测感染风险和控制通风。但很少有研究对比非稳态和稳态WR模型应用在通风策略上的区别。为了填补这一空白,本文探究了基于非稳态和稳态WR模型的通风策略对于防疫和建筑能耗的影响。首先,对常用的非稳态和稳态WR模型进行改进。一些之前被忽略的参数被加入到WR模型中,例如起始病毒浓度。然后,基于非稳态和稳态WR模型,提出并对比了两种通风策略。最后,将一栋位于加拿大的建筑物选作案例进行结果展示。案例显示,当起始病毒浓度较高(0.3 q/m^(3))且室内人员无其他保护措施时,基于稳态WR模型的通风策略会低估所需要的通风量。此时,非稳态WR模型通风策略的能耗可达稳态WR模型通风策略的2.5倍。

关键词：建筑通风 Wells-Riley模型建筑能耗空气传播

Influence of Island Scanning Strategy on Microstructures and Mechanical Properties of Direct Laser-Deposited Ti–6Al–4V Structures

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Acta Metallurgica Sinica(English Letters) 2019年第9期32卷 1173-1180页

作者： Xiao Wang Fei Lv Li-da.Shen Hui-Xin Liang De-Qiao Xie Zong-Jun Tian College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

To investigate the influence of island scanning on the microstructures and mechanical properties of direct laser-deposited Ti–6 Al–4 V structures,two samples are prepared using island scanning and orthogonal successive scanning,*** microstructures,relative density,and mechanical properties of the samples prepared using these two scanning strategies are *** sample exhibits columnarβ-grain morphology and basket-weave microstructure *** grains of the sample prepared using island scanning are significantly finer than that prepared by orthogonal successive scanning due to faster cooling during ***,the relative density of the sample prepared using island scanning was slightly smaller due to the concentration of lack-of-fusion pores at the overlap zone of the *** testing at room temperature indicates that the ultimate tensile strength and yield strength of the sample prepared using island scanning is enhanced due to finer grains,while the ductility of the sample is weakened due to defects.

关键词： Direct laser deposition Ti-6A1W Scanning strategies Microstructure Defects Mechanical property

Role of Triggering Receptor Expressed on Myeloid Cell-1 Expression in Mammalian Target of rapamycin Modulation of CD8＋ T-cell Differentiation during the Immune Response to Invasive Pulmonary Aspergillosis

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Chinese Medical Journal 2017年第10期130卷 1211-1217页

作者： Na Cui Hao Wang Long-Xiang Su Jia-Hui Zhang Yun Long da.Wei Liu Department of Critical Care Medicine Peking Union Medical College Hospital Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100730 China

Background： Triggering receptor expressed on myeloid cell- 1 （TREM- 1） may play a vital role in mammalian target ofrapamycin （mTOR） modulation ofCD8＋ T-cell differentiation through the transcription factors T-box expressed in T-cells and eomesodermin during the immune response to invasive pulmonary aspergillosis （IPA）. This study aimed to investigate whether the roTOR signaling pathway modulates the proliferation and differentiation of CD8＋ T-cells during the immune response to I PA and the role TREM-1 plays in this process. Methods： Cyclophosphamide （CTX） was injected intraperitoneally, and Asl？e;gillus.[mnigams spore suspension was inoculated intranasally to establish the immunosuppressed IPA mouse model. After inoculation, rapamycin （2 mg-kg ·d -1） or interleukin （IL）-12 （5 μg/kg every other da.） was given for 7 da.s. The number of CD8＋ effector memory T-cells （Tern）, expression of interferon （IFN）-y, roTOR, and ribosomal protein $6 kinase （S6K）, and the levels of IL-6, IL- 10, galactomannan （GM）, and soluble TREM- 1 （sTREM-I） were measured. Results： Viable A. fumigatus was cultured from the lung tissue of the inoculated mice. Histological examination indicated greater inflammation, hemorrhage, and lung tissue injury in both IPA and CTX ＋ IPA mice groups. The expression of mTOR and S6K was significantly increased in the CTX ＋ IPA ＋ I L- 12 group compared with the control, I PA （P = 0.01 ; P - 0.001 ）, and CTX ＋ 1PA （P = 0.034; P = 0.032） groups, but significantly decreased in the CTX ＋ IPA ＋ raPA group （P 〈 0.001 ）. Compared with the CTX ＋ IPA group, the proportion of Tern, expression of IFN-y, and the level ofsTREM-I were significantly higher after IL-12 treatment （P = 0.024, P = 0.032, and P = 0.017, respectively）, and the opposite results were observed when the roTOR pathway was blocked by rapamycin （P 〈 0.001）. Compared with the CTX ＋ I PA and CTX ＋ I PA ＋ raPA groups, IL-12 treatment increased IL-6 and downregulated IL- 10 as well as G M, which strengthened

关键词： CD8+ T Effector Memory Cells lmmunosuppression Invasive Pulmonary Aspergillosis Mammalian Target ofrapamycin Triggering Receptor Expressed on Myeloid Cell-1