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Chinese Journal of Mechanical Engineering 2018年第6期31卷 55-67页

作者： shi-yu wang Chanannipat Meesap School of Mechanical Engineering Tianjin University 300072 Tianjin China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin University 300072 Tianjin China

Time?variant excitations in planetary gear trains can cause excessive noise and vibration and even damage the system on a permanent basis. This paper focuses on the elastic vibrations of a helical planetary ring gear subjected to mesh and planet?pass excitations. Motivated by the structure, excitation and deformation symmetries, this paper proposes dual?frequency superposition and modulation methods to capture the mesh and sideband vibrations. The transi?tion between ring gear tooth and planet is introduced to address the excitations and vibrations. The phasing e ect of ring gear tooth and planet on various deformations is formulated. The inherent connections between the two types of vibrations are identified. The vibrations share identical exciting rules and the wavenumber and modulating signal order both equal the linear combination of tooth and planet counts. The results cover in?plane bending and extensional, out?of?plane bending and torsional deformations. Main findings are verified by numerical calculation and comparisons with the open literature. The analytical expressions can be used to determine whether the sideband is caused by component fault or only by elastic vibration. The methods can be extended to other power?transmission systems because little restriction is imposed during the analysis.

关键词： Helical planetary ring gear Typical vibration modes Planet phasing Sideband

Response Sensitivity to Design Parameters of RV Reducer

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 115-127页

作者： yu-Hu Yang Chuan Chen shi-yu wang School of Mechanical Engineering Tianjin University

Dynamic characteristic significantly a ects performance of RV reducer. The current researches mainly pay attention to free vibration properties of RV reducer. In order to satisfy the increasing demand on high performance,response sensi?tivity is analytically studied on the basis of cyclic symmetry structure. Based on the structure characteristics,a dynamic model is developed by taking into account the influence of bearing sti ness,crankshaft bending sti ness and mesh sti ness within planetary and cycloidal stages. For the model,governing equation of motion is derived and solved by Fourier series method. The solution revealed that forced vibrations at primary frequency are well defined structural. There exist three typical forced vibration modes: rotational,translational and planetary component modes. Response sensitivity to basic design parameters is obtained as closed?form expressions by di erential method. With the typical vibration modes,response sensitivity is simplified and classified into three types. Calculation of sensitivity implies that vibrations of the output wheel are sensitive to eccentricity. As eccentricity increases,sensitivity of translation decreases first and then increases,but sensitivity of rotation always increases. The proposed method for analyzing response sensi?tivity provides some principles for selecting parameters for RV reducer from the point of view of forced vibration.

关键词： RV reducer Mesh phasing Vibration modes Sensitivity

Towards full predictions of temperature dynamics in McNary Dam forebay using OpenFOAM

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Water Science and Engineering 2013年第3期6卷 317-330页

作者： yu-shi wang Marcela POLITANO Ryan LAUGHERY IIHR-Hydroscience and Engineering The University of Iowa Iowa City U.S. Army Corps of Engineers Walla Walla District Walla Walla

Hydroelectric facilities impact water temperature; low velocities in a reservoir increase residence time and enhance heat exchange in surface layers. In this study, an unsteady three-dimensional model was developed to predict the temperatm＇e dynamics in the McNary Dam forebay. The model is based on the open-source code OpenFOAM. RANS equations with the Boussinesq approximation were used to solve the flow field. A： realizable k-ε model that accounts for the production of wind turbulence was developed. Solar radiation and convective heat transfer at the free surface were included. The result of the model was compared with the field data collected on August 18, 2004. Changes in diurnal stratification were adequately predicted by the model. Observed vertical and lateral temperature distributions were accurately captured. Results indicate that the model can be used as a numerical tool to assess structural and operational alternatives to reduce the forebay temperature.

关键词： three-dimensional numerical simulation," water temperature," reservoir," thermal dynamics OpenFOAM McNary Dam forebay

Resistance of the flow over rough surfaces

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Journal of Hydrodynamics 2021年第3期33卷 593-601页

作者： yu Han shi-yu wang Jian Chen Shuqing Yang Liu-chao Qiu Nadeesha Dharmasir College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China College of Engineering China Agricultural UniversityBeijing100083China School of Civil Mining and Environmental EngineeringUniversity of WollongongWollongongAustralia

The mechanism of the flow resistance in open channels and pipelines is of vital importance for various critical issues related to the water *** Nikurade’s method of calculating the friction factor is not applicable in some *** is necessary to consider the influence of the vortex volume surrounding the vegetation and to study the hydrodynamic characteristics of the vegetated *** paper analyzes the variation of the vortices created by the surface roughness of different types and different sizes and proposes new definitions of the hydraulic radius and the equivalent roughness *** consideration of the skin friction and the form drag,on the basis of the force balance equation,a novel calculation method is used for the friction factor,and this method is verified by experimental *** hydrodynamic mechanism of the flow resistance revealed in this study may serve as a theoretical basis for hydraulic engineers to calculate the friction factor.

关键词： Hydraulic radius skin friction form drag friction factor separation zone dead fluid volume

Solid oxide membrane-assisted electrolytic reduction of Cr_(2)O_(3) in molten CaCl_(2)

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International Journal of Minerals,Metallurgy and Materials 2020年第12期27卷 1626-1634页

作者： Bo wang Chao-yi Chen Jun-qi Li Lin-zhu wang yuan-pei Lan shi-yu wang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Metallurgical Engineering and Process Energy Saving Guiyang 550025China

Solid oxide membrane-assisted electrolytic reduction of solid Cr_(2)O_(3) to Cr in molten CaCl_(2) was performed using a sintered porous Cr_(2)O_(3) cathode paired with an yttria-stabilized zirconia(YSZ)tube anode containing carbon-saturated liquid copper *** of the reduction mechanism,ion migration behavior,and effects of cathode pellet porosity and particle size on the electrolysis products and reduction rate revealed that the cathode microstructure and electrolytic conditions were key factors influencing the electrolysis *** results were obtained when the cathode was characterized by high porosity and a small particle size because this combination of features contributed to ion *** electrochemical activation was observed when cathode pellets prepared by 4 MPa molding followed by 2 h of sintering at 1150℃ were *** electrode reduction process(Cr^(3+)→Cr^(2+)→Cr)was promoted by high electrode voltages,and Cr metal was efficiently *** proposed method appears to be well suited for electrolytic Cr production because it does not require expensive pre-electrolysis techniques or generate harmful by-products.

关键词： solid oxide membrane yttria-stabilized zirconia electrometallurgy chromium molten salt

Synthesis and characterization of conjugated polymer containing azobenzene and oxadiazole units

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Chinese Chemical Letters 2009年第2期20卷 235-237页

作者： yue Zhang shi Jun yu Lu wang Cong Li College of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 China

A novel conjugated polymer containing azobenzene and oxadiazole units was synthesized through multi-step synthesis. The structures and properties of monomer and polymer were characterized and evaluated with IR, ^1H NMR, UV, TGA and GPC, respectively. Polymer with long side chain of alkoxy shows good solubility, thermal stability and photoisomerization property.

关键词： Oxadiazole Conjugated polymer Synthesis Characterization

Identification of natural compounds targeting Annexin A2 with an anti-cancer effect

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Protein & Cell 2018年第6期9卷 568-579页

作者： yu-shi wang He Li Yang Li Hongyan Zhu Ying-Hua Jin Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education College of Life Science Jilin University Changchun 130012 China

Annexin A2, a multifunctional tumor associated protein, promotes nuclear factor-kappa B （NF-κB） activation by interacting with NF-κB p50 subunit and facilitating its nuclear translocation. Here we demonstrated that two ginsenosides Rg5 （G-Rg5） and Rkl （G-Rkl）, with similar structure, directly bound to Annexin A2 by molecular docking and cellular thermal shift assay. Both Rg5 and Rkl inhibited the interaction between Annexin A2 and NF-κB p50 subunit, their translocation to nuclear and NF-κB activation. Inhibition of NF-κB by these two gin- senosides decreased the expression of inhibitor of apoptosis proteins （lAPs）, leading to caspase activation and apoptosis. Over expression of K302A Annexin A2, a mutant version of Annexin A2, which fails to interact with G-Rg5 and G-Rkl, effectively reduced the NF-κB inhibitory effect and apoptosis induced by G-Rg5 and G-Rkl. In addition, the knockdown of Annexin A2 largely enhanced NF-κB activation and apoptosis induced by the two molecules, indicating that the effects of G-Rg5 and G-Rkl on NF-κB were mainly mediated by Annexin A2. Taken together, this study for the first time demon- strated that G-Rg5 and G-Rkl inhibit tumor cell growth by targeting Annexin A2 and NF-κB pathway, and G-Rg5 and G-Rkl might be promising natural compounds for targeted cancer therapy.

关键词： Annexin A2 G-Rg5 G-Rkl HCC NF-κB

Inherent relationship between process parameters,crystallization and mechanical properties of continuous carbon fiber reinforced PEEK composites

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Defence Technology（防务技术） 2023年第6期24卷 269-284页

作者： Xiao-long Ma Li-hua Wen shi-yu wang Jin-you Xiao Wen-hao Li Xiao Hou School of Astronautics Northwestern Polytechnical UniversityXi'an710072China China Aerospace Science and Technology Corporation Beijing100048China

High-performance thermoplastic composites have been developed as significant structural materials for cutting-edge equipment in the aerospace and defence ***,the internal mechanism of processing parameters on mechanical properties in the manufacturing process of thermoplastic composite structures is still a serious *** purpose of this study is to investigate the process/crystallization/property relationships for continuous carbon fiber(CF)reinforced polyether-ether-ketone(PEEK)*** composite laminates are fabricated according to orthogonal experiments via the thermoforming *** mechanical performance is investigated in terms of crystallization properties and fracture morphology *** results show that the mechanical performance and crystallization properties of thermoplastic composites are significantly affected by the coupling of processing *** increased molding temperature,pressure,and holding time improve the degree of fiber/matrix infiltration and affect the crystallinity and crystalline morphology of the matrix,which further influences the mechanical properties of the *** is reflected in the test results that crystallinity has an approximately linear effect on mode-I interlaminar fracture toughness and transverse flexural *** well as the higher molding temperature can destroy the pre-existent crystals to improve the toughness of the matrix,and the well-defined crystalline structures can be observed when fabricated at higher temperatures and longer periods of holding time.

关键词： Polymer matrix composites Thermoplastic Processing parameters Mechanical properties Crystallization

Synthesis of mono-substituted derivatives of 6-aminoquinoline

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Chinese Chemical Letters 2011年第3期22卷 253-255页

作者： Tian Lan Xian Xia yuan Jiang Hong yu Chao Jia yu shi wang Hui Juan Zhang Zi Feng Ma Wei Dong Ye School of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 China School of Pharmacy Shanghai Jiaotong University Shanghai 200240 China Xinchang Pharmaceutical Factory Zhejiang Pharmaceutics Co. Ltd. Xinchang 312500 China

Several 6-aminoquinoline derivatives,which could be used in drug design,have been *** reaction conditions were comparatively studied,and the p-chloroaniline was used as optimum oxidant in Skraup-Doebner-Von Miller ***... 详细信息

关键词： 6-Aminoquinoline 6-Nitroquinoline Skraup reaction Oxidant

Sedimentary environment controls on the accumulation of organic matter in the Upper Ordovician Wufeng–Lower Silurian Longmaxi mudstones in the Southeastern Sichuan Basin of China

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Petroleum Science 2019年第1期16卷 44-57页

作者： Lei Yang Bo Ran yu-yue Han Shu-Gen Liu yue-Hao Ye Christopher Xiao Wei Sun Di Yang Guo-Dong Xia shi-yu wang School of Earth Sciences and Resources China University of Geosciences State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology University of Houston Research Institute of Yanchang Petroleum (Group) Co.Ltd

The Upper Ordovician–Lower Silurian mudstones(including the Wufeng, Guanyinqiao and Longmaxi Formations) in the Sichuan Basin are some of the most important shale gas plays in China. In order to enhance our understanding of the process of formation of organic carbon up to 10%, optical, microscopy and geochemical methods have been used to investigate the petrographic and geochemical characteristics of the formation. Firstly, three mudstone lithofacies were identified based on a wide variety of mudstone laminations. These are:(a) indistinctly laminated mudstone;(b) parallellaminated mudstone; and(c) nonparallel-laminated mudstone. Then, combining with the evidence from depocenter migration, Th/U ratios and total organic carbon, the abundant organo-minerallic fabrics suggest that organic carbon was preferentially deposited and preserved in anoxic, low energy and stagnant water conditions during deposition of the Wufeng and Longmaxi Formations. On the contrary, the Guanyinqiao Formation with poor organic carbon was deposited in oxic and high-energy water conditions.

关键词： Guanyinqiao Formation Sichuan Basin Mudstone Laminated mudstone Water condition