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なにガ,おんだガ,なんとガ
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作者 石工 《东北亚外语研究》 1999年第1期41-43,共3页
关键词 词的用法 发面力 截止期限 “是什么” 总觉得 代词 词形式 全一样 达到目的 简体
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向高起点、高标准、高效率目标迈进
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作者 龚叶 《中国远洋航务》 1999年第10期45-45,共1页
中远工业公司是中国远洋运输(集团)总公司的真属企业,1993年12月18日下工成立,经过5年多的市场洗礼,如今的中远工业公司拥有3家全资企业,20家合资企业,总资产达110多亿元人民币。 中远工业公司在对中远工业企业衽统一管理的同时,积极开... 中远工业公司是中国远洋运输(集团)总公司的真属企业,1993年12月18日下工成立,经过5年多的市场洗礼,如今的中远工业公司拥有3家全资企业,20家合资企业,总资产达110多亿元人民币。 中远工业公司在对中远工业企业衽统一管理的同时,积极开拓新项目,走出了一条航运工业与非航运工业并进,以船舶工业为龙头,集造修船舶、集装箱、化工涂料、能源电力、钢结构工程、工程设备及贸易、高新技术产业为一体的多元化发展道路。从名列“修船产值、人均利税、坞修周期、修船吨位”四个全国第一的大型船舶修理工业基地,到拥有全国近一半的海运集装箱生产能力、享誉海内外的集装箱制造企业。中远工业已形成了一系列实力强劲的规模工业体系。中远工业企业在“九五”期间将全部通过ISO9000认证,一批刚筹建的新项目已经陆续建成投产,在技术引进、市场拓展、人才培育、内部管理发面力争体现高起点、高标准、高效率、为企业发展奠定坚实基础。 展开更多
关键词 中远 高起点 高效率 修船基地 发面力 万吨级 空港设备 钢结构制造 海运集装箱 工业企业
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Analysis of Earthquake-Triggered Failure Mechanisms of Slopes and Sliding Surfaces 被引量:11
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作者 WANG Jian YAO Lingkan Arshad Hussain 《Journal of Mountain Science》 SCIE CSCD 2010年第3期282-290,共9页
Earthquake-induced landslides along the Dujiangyan-Yingxiu highway after the Ms 8.0 Wenchuan earthquake in 2008 were investigated. It was found that: (1) slopes were shattered and damaged during the earthquake a... Earthquake-induced landslides along the Dujiangyan-Yingxiu highway after the Ms 8.0 Wenchuan earthquake in 2008 were investigated. It was found that: (1) slopes were shattered and damaged during the earthquake and open tension cracks formed on the tops of the slopes; (2) the upper parts of slopes collapsed and slid, while the lower parts remained basically intact, indicating that the upper parts of slopes would be damaged more heavily than the lower parts during an earthquake. Large-scale shaking table model tests were conducted to study failure behavior of slopes under the Wenchuan seismic wave, which reproduced the process of deformation and failure of slopes. Tension cracks emerged at the top and upper part of model, while the bottom of the model remained intact, consistent with field investigations. Depth of the tension crack at the top of model is 32 cm, i.e., 3.2 m compared to the prototype natural slope with a height of 14 m when the length scale ratio (proto/model) is lo. Acceleration at the top of the slope was almost twice as large as that at the toe when the measured accelerations on shaking table are 4.85 m/s2 and 6.49 m/s2, which means that seismic force at the top of the slope is twice the magnitude of that at the toe. By use of the dynamic-strength-reduction method, numerical simulation was conducted to explore the process and mechanism of formation of the sliding surface, with other quantified information. The earthquake-induced failure surfaces commonly consist of tension cracks and shear zones. Within 5 mfrom the top of the slope, the dynamic sliding surface will be about 1 m shallower than the pseudo-static sliding surface in a horizontal direction when the peak ground acceleration (PGA) is 1 m/s2; the dynamic sliding surface will be about 2 m deeper than the pseudo-static sliding surface in a horizontal direction when the PGA is lo m/sL and the depths of the dynamic sliding surface and the pseudo-static sliding surface will be almost the same when the PGA is 2 m/s2. Based on these findings, it is suggested that the key point of anti-seismic design, as well as for mitigation of post-earthquake, secondary mountain hazards, is to prevent tension cracks from forming in the upper part of the slope. Therefore, the depth of tension cracks in slope surfaces is the key to reinforcement of slopes. The depth of the sliding surface from the pseudo-static method can be a reference for slope reinforcement mitigation. 展开更多
关键词 Subgrade engineering slope failuremechanism shaking table model test: seismicsliding surface Wenchuan earthquake
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Influence of interface morphology on dynamic behavior and energy dissipation of bi-material discs 被引量:1
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作者 Zi-long ZHOU Jian-you LU +1 位作者 Xin CAI Yi-chao RUI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2339-2352,共14页
To investigate the dynamic behavior and energy dissipation of the rock−concrete interface,dynamic splitting tests on bi-material discs were conducted by using the split Hopkinson pressure bar.The test results reveal t... To investigate the dynamic behavior and energy dissipation of the rock−concrete interface,dynamic splitting tests on bi-material discs were conducted by using the split Hopkinson pressure bar.The test results reveal that with the change of the interface inclination angles(θ),the influence of interface groove width on the bearing capacity of specimens also varies.Whenθincreases from 0°to 30°,the bearing capacity of the specimen increases first and then decreases with the rise of the interface groove width;the optimal groove width on the rock surface in this range of interface inclination angles is 5 mm.Whenθincreases from 45°to 90°,the bearing capacity of the specimen has no obvious change.Moreover,whenθincreases from 0°to 45°,the dissipated energy of the specimens rises obviously at first and then tends to be stable as the width of the interface groove increases. 展开更多
关键词 rock−concrete interface Brazilian disc splitting fracture development interface mechanical properties dynamic behavior energy dissipation
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A Surface Femtosecond Two-Photon Photoemission Spectrometer for Excited Electron Dynamics and Time-Dependent Photochemical Kinetics
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作者 任洋峰 周传耀 +7 位作者 马志博 肖春雷 毛新春 戴东旭 Jerry LaRueb Russell Cooper Alec M. Wodtke 杨学明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第3期255-261,I0001,共8页
A surface femtosecond two-photon photoemission (2PPE) spectrometer devoted to the study of ultrafast excited electron dynamics and photochemical kinetics on metal and metal oxide surfaces has been constructed. Low e... A surface femtosecond two-photon photoemission (2PPE) spectrometer devoted to the study of ultrafast excited electron dynamics and photochemical kinetics on metal and metal oxide surfaces has been constructed. Low energy photoelectrons are measured using a hemispherical electron energy analyzer with an imaging detector that allows us to detect the energy and the angular distributions of the photoelectrons simultaneously. A Mach-Zehnder interferom- eter was built for the time-resolved 2PPE (TR-2PPE) measurement to study ultrafast surface excited electron dynamics, which was demonstrated on the Cu(111) surface. A scheme for measuring time-dependent 2PPE (TD-2PPE) spectra has also been developed for studies of surface photochemistry. This technique has been applied to a preliminary study on the photochemical kinetics on ethanol/TiO2(110). We have also shown that the ultrafast dynamics of photoinduced surface excited resonances can be investigated in a reliable way by combining the TR-2PPE and TD-2PPE techniques. 展开更多
关键词 Femtosecond two-photon photoemission spectropy TIME-RESOLVED Ultrafast excited electron dynamics Surface photochemical kinetics
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The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi 被引量:6
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作者 张晓冬 付勇 +1 位作者 李志义 赵宗昌 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期896-903,共8页
The idea that the collapse proceeds from the outer boundary of the cavity cloud towards its center for the ultrasonic cavitation proposed by Hasson and Morch in 1980s is further developed for calculating the collapse ... The idea that the collapse proceeds from the outer boundary of the cavity cloud towards its center for the ultrasonic cavitation proposed by Hasson and Morch in 1980s is further developed for calculating the collapse pressure and boundaries of cavity cloud at the collapse stage of bubbles for hydraulic cavitation flow in Venturi in present research. The numerical simulation is carried out based on Gilmore's eouations of bubble dynamics, which take account of the compressibility of fluid besides the viscosity and interfacial tension. The collapse of the cavity cloud is considered to proceed layer by layer from the outer cloud towards its inner part. The simulation results indicate that thepredicted boundaries of the cavity cloudat the collapse stage agree.well with the exPerimental ones.It is also found that the maximum collapse pressure of the cavity cloud is several times as high as the collapse pressure of outside boundary, and it is located at a point in the axis, where the cavity cloud disappears completely. This means that a cavity cloud has higher collapse pressure or strength than that of a single bubble due to the interactions of the bubbles. The effects of operation and structural parameters on the collapse pressure are also analyzed in detail. 展开更多
关键词 cavity cloud collapsing layer by layer laydrodynamic cavitation collapse pressure bubble dynamics
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Strong ground movement induced by mining activities and its effect on power transmission structures 被引量:3
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作者 DAI Kao-shan CHEN Shen-en 《Mining Science and Technology》 EI CAS 2009年第5期563-568,共6页
Surface mining activities may introduce damages to nearby infrastructure. Concerns are put forward by the power company about structural integrity of electric power transmission structures in areas where coal mining a... Surface mining activities may introduce damages to nearby infrastructure. Concerns are put forward by the power company about structural integrity of electric power transmission structures in areas where coal mining activities cause strong ground vibrations. Common practice in the power industry is to limit ground motion by specifying maximum Peak Particle Velocity. So far, there is a lack of industry-wide recognized guidelines on how ground vibration limits should be set for the transmission structures. In order to develop a defense strategy to protect power transmission lines against strong ground motions in mining areas, a systematic research work was conducted to establish strong ground vibration characteristics and to study impacts of ground excitations on transmission pole structures. Ground movements were recorded using geophones and wireless tri-axial sensing units. The process of generating ground motion response spectra via analyzing actual ground motion measurements is described in the paper. These spectra developed based on peak particle velocities were used as a basis for spectral analysis performed using validated Finite Element models to obtain structural displacements, reactions and stress states of the transmission pole structures in the mining sites. A quantitative ground motion limit was established by comparing structural responses with the corresponding design requirements. 展开更多
关键词 transmission structure ground motion structural response
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A decision hyper plane heuristic based artificial immune network classification algorithm 被引量:4
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作者 DENG Ze-lin TAN Guan-zheng +1 位作者 HE Pei YE Ji-xiang 《Journal of Central South University》 SCIE EI CAS 2013年第7期1852-1860,共9页
Most of the developed immune based classifiers generate antibodies randomly, which has negative effect on the classification performance. In order to guide the antibody generation effectively, a decision hyper plane h... Most of the developed immune based classifiers generate antibodies randomly, which has negative effect on the classification performance. In order to guide the antibody generation effectively, a decision hyper plane heuristic based artificial immune network classification algorithm (DHPA1NC) is proposed. DHPAINC taboos the inner regions of the class domain, thus, the antibody generation is limited near the class domain boundary. Then, the antibodies are evaluated by their recognition abilities, and the antibodies of low recognition abilities are removed to avoid over-fitting. Finally, the high quality antibodies tend to be stable in the immune network. The algorithm was applied to two simulated datasets classification, and the results show that the decision hyper planes determined by the antibodies fit the class domain boundaries well. Moreover, the algorithm was applied to UCI datasets classification and emotional speech recognition, and the results show that the algorithm has good performance, which means that DHPAINC is a promising classifier. 展开更多
关键词 artificial immune network decision hyper plane recognition ability CLASSIFICATION
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Effect of flank angle and friction coefficient on contact stress of turbine rotor 被引量:1
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作者 WU Xiao-zan TAO Qing-bin +1 位作者 CHEN An-ping XU Hui 《Journal of Central South University》 SCIE EI CAS 2013年第7期1792-1796,共5页
In order to simulate the stress of turbine rotor in aeroengine, based on the ANSYS, the simplification model of the turbine rotor was built up. By applying the simplification model, the contact stress of turbine rotor... In order to simulate the stress of turbine rotor in aeroengine, based on the ANSYS, the simplification model of the turbine rotor was built up. By applying the simplification model, the contact stress of turbine rotor was computed. The maximum contact stress appears at the chamfer below the flank, which agrees with experiment result. At the same time, the contact stress changing with the flank angle and friction coefficient was calculated, The results show that the contact stress in the flank increases slowly with the increase of flank angle; with the friction coefficient increasing, the contact stress in flank length decreases; the contact stress will not change when the friction coefficient is over 0.25. 展开更多
关键词 AEROENGINE contact stress ANSYS optimization design
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Effects of Pressure on Bubble Size and Separation of BSA by a Semi-batch Foaming Process
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作者 申秋华 王晓杰 《Agricultural Science & Technology》 CAS 2013年第10期1503-1506,1512,共5页
Experiments were conducted to obtain the values of the Sauter bubble size, enrichment and recovery of bovine serum albumin (BSA) in a semi-batch col- umn fitted with a stainless steel sparger at elevated pressure. T... Experiments were conducted to obtain the values of the Sauter bubble size, enrichment and recovery of bovine serum albumin (BSA) in a semi-batch col- umn fitted with a stainless steel sparger at elevated pressure. The effects of Sur- face tension, surfactant concentration, foam/solution height ratio and air flow rate on the separation performance were investigated, and the results showed that good en- richments and recoveries can be achieved for bovine serum albumin operated at el- evated pressures. Especially the size of bubbles generated by the stainless steel sparger was smaller at higher pressures which is favorable to the foam separation process. Furthermore, the separation mechanism of bovine serum albumin operated at elevated pressure was also discussed. 展开更多
关键词 Foam separation PRESSURE Bubble size Enrichment and recovery ratio
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Energy dissipation through wind-generated breaking waves 被引量:1
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作者 张书文 曹瑞雪 谢玲玲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第5期822-825,共4页
Wave breaking is an important process that controls turbulence properties and fluxes of heat and mass in the upper oceanic layer.A model is described for energy dissipation per unit area at the ocean surface attribute... Wave breaking is an important process that controls turbulence properties and fluxes of heat and mass in the upper oceanic layer.A model is described for energy dissipation per unit area at the ocean surface attributed to wind-generated breaking waves,in terms of ratio of energy dissipation to energy input,windgenerated wave spectrum,and wave growth rate.Also advanced is a vertical distribution model of turbulent kinetic energy,based on an exponential distribution method.The result shows that energy dissipation rate depends heavily on wind speed and sea state.Our results agree well with predictions of previous works. 展开更多
关键词 near-surface dynamics energy dissipation wave breaking
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Effects of Hydroxyl Groups in Organic Ammonium Counterions on the Properties of Fluorinated Surfactants
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作者 Zhang Tiantian Zhou Hongyu +2 位作者 Wu Bowan Xiao Jinxin Xing Hang 《China Detergent & Cosmetics》 2017年第4期57-65,共9页
The surface tension, foaming and viscosity for C7F15COO^-N^+H(C2H4OH)χ(C2Hs)3-x and C8F17SO3- N^+H(C2H4OH)χ(C2H5)3-χ (x = 0, 1, 2, 3) were measured to systematically study the effects of hydroxyl groups... The surface tension, foaming and viscosity for C7F15COO^-N^+H(C2H4OH)χ(C2Hs)3-x and C8F17SO3- N^+H(C2H4OH)χ(C2H5)3-χ (x = 0, 1, 2, 3) were measured to systematically study the effects of hydroxyl groups in organic ammonium counterions on the properties of perfluorooctanoates and perfluorooctanesulfonates. The results showed that the critical micelle concentration (cmc) and the surface tension at cmc (γcmc) were both increased with the increase of number of hydroxyl groups (χ) in the two series. The perfluorooctanesulfonate had smaller cmc but higher γ=cmc than perfluorooctanoate with the same counterion. The minimum molecular area of surface adsorption (Amin) of C8F17zSO3^-N^+H(C2H4OH)χ(C2H5)3-χ were 0.64, 0.57, 0.63 and 0.72 nm^2 while the Amin values of C7F15COO^-N^+H(C2H4OH)χ(C2H5)3-χ were 0.61, 0.62, 0.61 and 0.71 nm^2 when χ = 0, 1, 2 and 3, respectively. For the investigated systems of surfactants, the results of foam expansion ratio agreed with those of surface activity, while the 25% drainage time were consistent with the results of viscosity. 展开更多
关键词 COUNTER-ION organic ammonium ion fluorocarbon surfactant foam surface activity MICELLIZATION
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A Virtual Work Approach to Modeling the Nonlinear Behavior of Steel Frames
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作者 Barry T.Rosson 《Journal of Civil Engineering and Architecture》 2018年第5期323-334,共12页
The stiffness reduction is studied in detail of compact W-Shapes (wide-flange steel shapes) that results from yielding of the cross-section due to uniaxial bending and axial compression. Three-dimensional m-p-τ su... The stiffness reduction is studied in detail of compact W-Shapes (wide-flange steel shapes) that results from yielding of the cross-section due to uniaxial bending and axial compression. Three-dimensional m-p-τ surface plots developed from detailed fiber element models of a W8x31 are used to develop a generalized material model for direct implementation in the virtual work method. A portal steel frame is used to illustrate the virtual work method with the nonlinear material model in a first-order, inelastic analysis implementation and in a second-order, inelastic analysis condition. The nonlinear modeling capabilities of MASTAN2 are used to verify the accuracy of the virtual work results and are found to be in very close agreement. 展开更多
关键词 Nonlinear analysis steel beam-columns stiffness reduction material model virtual work.
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A Guide to the Influence of Ground Reaction on Ship Stability
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作者 Ahmed Helmy Abouelfadl Essam Eldin Youssef Abdelraouf 《Journal of Shipping and Ocean Engineering》 2017年第6期262-273,共12页
Grounded ship faces up exceptionally different stability forces unlike in her normal operating condition. This critical situation must be corrected as soon as can minimize hull stress, the risk of pollution and stabil... Grounded ship faces up exceptionally different stability forces unlike in her normal operating condition. This critical situation must be corrected as soon as can minimize hull stress, the risk of pollution and stability failure. Re-floating the ship need full understanding of the impact of ground reaction (R) on the ship buoyancy and stability. Re-floating the ship has different phases and there are several immediate actions that should be taken by ship's crew; one of these phases is re-calculation of ship stability conditions. In this paper, a guide to understanding the effect of the ground reaction (R), determines the amount of ground pressure and its location. With consideration of the seabed form whether symmetric of asymmetric. Calculating the magnitude of the ground reaction (R) using different applicable methods, explaining the effect of using weight to re-float the ship by her own means, focusing on GM calculation after grounding. 展开更多
关键词 Ship grounding ground reaction (R) ground pressure (P) neutral loading point and ship re-floating.
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Aerodynamic Performances of Wind Turbine Airfoils Using a Panel Method
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作者 M.M. Oueslati A.W. Dahmouni +3 位作者 M. Ben Salah F. Askri C. Kerkeni S. Ben Nasrallah 《Journal of Environmental Science and Engineering》 2011年第9期1175-1182,共8页
One of the key features of Laplace's Equation is the property that allows the equation governing the flow field to be converted from a 3D problem throughout the field to a 2D problem for finding the potential on the ... One of the key features of Laplace's Equation is the property that allows the equation governing the flow field to be converted from a 3D problem throughout the field to a 2D problem for finding the potential on the surface. The solution is then found using this property by distributing "singularities" of unknown strength over discretized portions of the surface: panels. Hence the flow field solution is found by representing the surface by a number of panels, and solving a linear set of algebraic equations to determine the unknown strengths of the singularities. In this paper a Hess-Smith Panel Method is then used to examine the aerodynamics of NACA 4412 and NACA 23015 wind turbine airfoils. The lift coefficient and the pressure distribution are predicted and compared with experimental result for low Reynolds number. Results show a good agreement with experimental data. 展开更多
关键词 Panel method wind turbine airfoils incompressible potential flow pressure distribution
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Evaporating behaviors of water droplet on superhydrophobic surface 被引量:2
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作者 HAO PengFei LV CunJing HE Feng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2463-2468,共6页
We investigated the dynamic evaporating behaviors of water droplet on superhydrophobic surfaces with micropillars.Our experimental data showed that receding contact angles of the water droplet increased with the decre... We investigated the dynamic evaporating behaviors of water droplet on superhydrophobic surfaces with micropillars.Our experimental data showed that receding contact angles of the water droplet increased with the decreasing of the scale of the micropillars during evaporation,even though the solid area fractions of the microstructured substrates remained constant.We also experimentally found that the critical contact diameters of the transition between the Cassie-Baxter and Wenzel states are affected not only by the geometrical parameters of the microstructures,but also by the initial volume of the water droplet.The measured critical pressure is consistent with the theoretical model,which validated the pressure-induced impalement mechanism for the wetting state transition. 展开更多
关键词 DROPLET EVAPORATION SUPERHYDROPHOBIC
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Vibration and flutter of wind turbine blade modeled as anisotropic thin-walled closed-section beam 被引量:4
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作者 LIU TingRui REN YongSheng 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第3期715-722,共8页
Based on a variational asymptotic analytical model, vibration and aeroelastic stability of rotor blades modeled as anisotropic thin-walled closed-section beams are systematically addressed. The analysis is applied to ... Based on a variational asymptotic analytical model, vibration and aeroelastic stability of rotor blades modeled as anisotropic thin-walled closed-section beams are systematically addressed. The analysis is applied to a laminated composite construction of the circumferentially asymmetric stiffness (CAS) that produces bending-twist coupling. The vibration characteristics of composite beam are determined by the Extended Galerkin Method. The unsteady aerodynamic loads and centrifugal force are integrated with the classical aerodynamic model to deal with aeroelastic stability analysis. The influence of some related factors, ply angle, rotating velocity, and wind speed, is investigated. The paper gives methods of eigenvalue analysis and aeroelastic response, and gives the approaches to restrain classical flutter. 展开更多
关键词 Extended Galerkin Method bending-twist coupling circumferentially asymmetric stiffness thin-walled closed-section beam FLUTTER
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Investigation of the influence of ultrasonic stirring on mass transfer in the through-mask electrochemical micromachining process 被引量:5
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作者 WANG QuanDai CAI XingXing +3 位作者 WANG Li LI PengYang XIAO JiMing LI Yan 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第2期250-256,共7页
Surface texturing is a widely accepted approach for friction reduction between mechanical components. Through-mask electrochemical mieromachining is a simple and reliable process for metal surface texturing in which m... Surface texturing is a widely accepted approach for friction reduction between mechanical components. Through-mask electrochemical mieromachining is a simple and reliable process for metal surface texturing in which mass transport conditions have profound influence on final machined quality. An ultrasonic stirrer is usually adopted for mass transfer enhancement. However, understanding of the effects of ultrasonic stirring on mass transfer is limited, and is far from sufficient for developing guidelines for its practical application. In this work, the influences of ultrasonic stirring parameters on mass transfer have been investigated numerically and experimentally. With the numerical method, periodic pressure change in the electrolyte over time has been obtained, showing that ultrasonic stirring results in drastic transient pressure change in electrolyte fluid fields. Parameters related to ultrasonic frequency, vibration amplitude, and the depth of anode surface immersed in the electrolyte solution influence pressure amplitude. Validation experiments have been conducted and etched surface profile and morphology characterized, which show that the experimental observations are in agreement with numerical predictions. With the optimized mass transfer, well-defined micro-pits array of 30 gm and a smooth etched surface on tin-bronze substrate in large scale have been demonstrated. 展开更多
关键词 surface texture through-mask electrochemical micromachining mass transfer ultrasonic stirring numerical simulation
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Estimation of tropical cyclone parameters and wind fields from SAR images 被引量:6
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作者 ZHOU Xuan YANG XiaoFeng +4 位作者 LI ZiWei YU Yang BI HaiBo MA Sheng LI XiaoFeng 《Science China Earth Sciences》 SCIE EI CAS 2013年第11期1977-1987,共11页
The traditional method of Synthetic Aperture Radar(SAR)wind field retrieval is based on an empirical relation between the near surface winds and the normalized radar backscatter cross section to estimate wind speeds,w... The traditional method of Synthetic Aperture Radar(SAR)wind field retrieval is based on an empirical relation between the near surface winds and the normalized radar backscatter cross section to estimate wind speeds,where this relation is called the geophysical model function(GMF).However,the accuracy rapidly decreases due to the impact of rainfall on the measurement of SAR and the saturation of backscattered intensity under the condition of tropical cyclone.Because of no available instrument synchronously monitoring rain rate on the satellite platform of SAR,we have to derive the precipitation of the SAR observation time from non-simultaneous passive microwave observations of rain in combination with geostationary IR images,and then use the model of rain correction to remove the impact of rain on SAR wind field measurements.For the saturation of radar backscatter cross section in high wind speed conditions,we develop an approach to estimate tropical cyclone parameters and wind fields based on the improved Holland model and the SAR image features of tropical cyclone.To retrieve the low-to-moderate wind speed,the wind direction of tropical cyclone is estimated from the SAR image using wavelet analysis.And then the maximum wind speed and the central pressure of tropical cyclone are calculated by a least square minimization of the difference between the improved Holland model and the low-to-moderate wind speed retrieved from SAR.In addition,wind fields are estimated from the improved Holland model using the above-mentioned parameters of tropical cyclone as input.To evaluate the accuracy of our approach,the SAR images of typhoon Aere,typhoon Khanun,and hurricane Ophelia are used to estimate tropical cyclone parameters and wind fields,which are compared with the best track data and reanalyzed wind fields of the Joint Typhoon Warning Center(JTWC)and the Hurricane Research Division(HRD).The results indicate that the tropical cyclone center,maximum wind speed,and central pressure are generally consistent with the best track data,and wind fields agree well with reanalyzed data from HRD. 展开更多
关键词 rain correction tropical cyclone parameters wind fields ESTIMATE SAR
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Nanoplasmonic colloidal suspensions for the enhance-ment of the luminescent emission from single-walled carbon nanotubes 被引量:3
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作者 Mareen Glaeske Antonio Setaro 《Nano Research》 SCIE EI CAS CSCD 2013年第8期593-601,共9页
Aiming to enhance the luminescence yield of carbon nanotubes, we introduce a new class of hybrid nanoplasmonic colloidal systems (π-hybrids). Nanotubes dispersed in gold nanorod colloidal suspensions yield hybrid s... Aiming to enhance the luminescence yield of carbon nanotubes, we introduce a new class of hybrid nanoplasmonic colloidal systems (π-hybrids). Nanotubes dispersed in gold nanorod colloidal suspensions yield hybrid structures exhibiting enhanced luminescence up to a factor of 20. The novelty of the proposed enhancement mechanism relies on including metal proximity effects in addition to its localized surface plasmons. This simple, robust and flexible technique enhances the luminescence of nanotubes with chiralities whose enhancement has never reported before, for example the (8,4) tube. 展开更多
关键词 carbon nanotubes luminescence enhancement gold nanorods nanoplasmonic colloids hybrid structures
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