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Applied Mathematics and Mechanics(English Edition) 2021年第7期42卷 981-998页

作者： Shaowu YANG Yuxin HAO Wei ZHANG Li YANG lingtao liu College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

In this study,the first-order shear deformation theory(FSDT)is used to establish a nonlinear dynamic model for a conical shell truncated by a functionally graded graphene platelet-reinforced composite(FG-GPLRC).The vibration analyses of the FG-GPLRC truncated conical shell are *** the graphene platelets(GPLs)of the FG-GPLRC truncated conical shell with three different distribution patterns,the modified Halpin-Tsai model is used to calculate the effective Young’s ***’s principle,the FSDT,and the von-Karman type nonlinear geometric relationships are used to derive a system of partial differential governing equations of the FG-GPLRC truncated conical *** Galerkin method is used to obtain the ordinary differential equations of the truncated conical ***,the analytical nonlinear frequencies of the FG-GPLRC truncated conical shell are solved by the harmonic balance *** effects of the weight fraction and distribution pattern of the GPLs,the ratio of the length to the radius as well as the ratio of the radius to the thickness of the FG-GPLRC truncated conical shell on the nonlinear natural frequency characteristics are *** study culminates in the discovery of the periodic motion and chaotic motion of the FG-GPLRC truncated conical shell.

关键词： nonlinear free vibration harmonic balance method functionally graded graphene platelet-reinforced composite(FG-GPLRC) truncated conical shell chaos

Simulation study on dynamics of cylindrical gear meshing with the evolution meshing stiffness

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仪器仪表学报 2016年第S1期37卷 146-151页

作者： Ma Chao liu lingtao Wang Shaohong Xu Xiaoli Peng Yumin Beijing Information Science and Technology University

Simulation study on the cylindrical gear meshing with the evolution gear meshing stiffness is being done for better understanding the dynamic characteristics of the *** consideration of damping,bearing clearance and gear backlash nonlinearity,the dynamic model is set up and computed in *** analysis about the relationship between the kinematic responses and the meshing stiffness are carried *** the results showed that as the gear mesh stiffness is changed from small to large,the performance of the system is changed from the harmonic stable periodic motion to with one times,two times,four times,ending chaos of the stability of the *** research results would have theoretical guidance value for the fault diagnosis in engineering.

关键词： cylindrical gear meshing stiffness bifurcation

Enhancing photo-generated carriers transfer of K-C_(3)N_(4)/UiO-66-NH_(2) with Er doping for efficient photocatalytic oxidation of furfural to furoic acid

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燃料化学学报（中英文） 2024年第11期52卷 1617-1628页

作者： WANG Haocun liu lingtao BIAN Junjie LI Chunhu Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China

Biomass-derived platform molecules,such as furfural,are abundant and renewable feedstock for valuable chemical *** is critical to synthesize highly efficient photocatalysts for selective oxidation under visible *** Er@K-C_(3)N_(4)/UiO-66-NH_(2) catalyst was synthesized using a straight-forward hydrothermal technique,and exhibited exceptional efficiency in the photocatalytic oxidation of furfural to furoic *** catalyst was thoroughly characterized,confirming the effective adjustment of the band gap energy of Er@K-C_(3)N_(4)/UiO-66-NH_(2).Upon the optimized reaction conditions,the conversion rate of furfural reached 89.3%,with a corresponding yield of furoic acid at 79.8%.The primary reactive oxygen species was identified as·O_(2)^(-) from ESR spectra and scavenger *** incorporation of Er and K into the catalyst enhanced the photogenerated carriers transfer rate,hence increasing the separating efficiency of photogenerated electron-hole *** study expands the potential applications of rare earth element doped g-C_(3)N_(4) in the photocatalytic selective oxidation of furfurans.

关键词： furfural furoic acid selective catalytic oxidation MOFs carbon nitride

Refining geoid and vertical gradient of gravity anomaly

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Geodesy and Geodynamics 2011年第4期2卷 1-9页

作者： Zhang Chijun Bian Shaofeng Yi Zhourun liu lingtao Fang Jian Institute of Geodesy and Geophysics Chinese Academy Science Wuhan 430077 China Naval Engineering University Wuhan 430033 China

We have derived and tested several relations between geoid （N） and quasi-geoid （~） with model validation. The elevation correction consists of the first-term （Bouguer anomaly） and second-term （vertical gradient of gravity anomaly）. The vertical gradient was obtained from direct measurement and terrain calcula- tion. The test results demonstrated that the precision of geoid can reach centimeter-level in mountains less than 5000 meters high.

关键词： refine geoid quasi-geoid gravity anomaly vertical gradient

考虑横向拉伸影响的FGM夹层板动不稳定性分析

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应用力学学报 2021年第2期38卷 638-648页

作者：王美祥郝育新刘令涛北京信息科技大学机电工程学院北京100192

以受多种形式面内载荷作用下的功能梯度夹层矩形板为研究对象,夹层板的功能梯度层组分材料沿厚度方向按幂律分布,考虑组分材料物性参数的温度相关性。研究中所用的位移场在Reddy高阶剪切变形理论基础上考虑了横向拉伸的影响。利用能量... 详细信息

以受多种形式面内载荷作用下的功能梯度夹层矩形板为研究对象,夹层板的功能梯度层组分材料沿厚度方向按幂律分布,考虑组分材料物性参数的温度相关性。研究中所用的位移场在Reddy高阶剪切变形理论基础上考虑了横向拉伸的影响。利用能量原理和Galerkin法得到四边简支功能梯度材料夹层矩形板的动力学模型。运用Bolotin法求得了系统的动不稳定区域。对比结果表明考虑横向拉伸影响时与文献中的对比更接近,并详细研究了几何物理参数、环境温度以及不同分布形式的面内外载荷对系统动不稳定区域的影响,结果表明:随着金属体积分数指数、长宽比、静态载荷参数、载荷比的增加,系统参数激励动不稳定区域的宽度增加;随着温差、长厚比、面内载荷分布系数的增加,系统参数激励动不稳定区域的宽度减小。

关键词：功能梯度材料夹层板横向拉伸不同载荷分布形式动不稳定性

股深动脉穿动脉穿支皮瓣在口腔颌面-头颈部缺损重建的应用进展

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中华耳鼻咽喉头颈外科杂志 2021年第11期56卷 1224-1228页

作者：刘凌涛王军邹海啸南昌大学第二附属医院口腔颌面外科 330006

各种原因引起的口腔颌面-头颈部缺损,常影响患者的语言、进食、吞咽等功能,并可能造成容貌损害,这会严重影响他们的生存质量甚至存活率。随着显微外科技术的发展,穿支皮瓣移植成为重建外科领域非常重要的技术手段之一。股深动脉穿动脉... 详细信息

各种原因引起的口腔颌面-头颈部缺损,常影响患者的语言、进食、吞咽等功能,并可能造成容貌损害,这会严重影响他们的生存质量甚至存活率。随着显微外科技术的发展,穿支皮瓣移植成为重建外科领域非常重要的技术手段之一。股深动脉穿动脉穿支皮瓣具有可观的穿支血管、充足的皮瓣面积、美观性能好且供区并发症少等优点,使其在口腔颌面-头颈部缺损重建的报道日益增多。

关键词：显微外科技术口腔颌面穿支皮瓣股深动脉穿动脉生存质量皮瓣面积穿支血管

工程教育专业认证背景下《工程制图》课程教学改革研究

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图学学报 2018年第4期39卷 786-790页

作者：杨莉郝育新刘令涛北京信息科技大学机电工程学院北京100192

工程教育专业认证是教育部为切实提升高等教育教学质量,推进工程教育国际互认和工程师资格国际互认的重要举措。工程教育专业认证的核心理念是"以学生为中心",提出以"能力培养"为导向的新的教育思想。针对"工程制图"课程目前存在的问题... 详细信息

工程教育专业认证是教育部为切实提升高等教育教学质量,推进工程教育国际互认和工程师资格国际互认的重要举措。工程教育专业认证的核心理念是"以学生为中心",提出以"能力培养"为导向的新的教育思想。针对"工程制图"课程目前存在的问题,且基于专业认证的要求,从课程体系、教学内容、教学方法和考核方式等方面进行了一些改革,探讨如何建立符合专业认证标准的教学模式,促进《工程制图》课程教学质量的持续改进和提升。

关键词：工程专业认证工程制图教学改革