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拼焊板V形自由弯曲精确回弹控制技术研究

机械工程学报 2014年第10期50卷 40-47页

作者：段永川官英平先进锻压成形技术与科学教育部重点实验室(燕山大学) 秦皇岛066004

在平截面和平面弯曲等假设条件下,建立拼焊板V形可适于小曲率自由弯曲回弹的解析预测模型,所建立的回弹预测模型将成形过程分段研究,即区分为贴模阶段和未贴模阶段。分别根据贴模态和未贴模态拼焊板弯矩分布特点,构建两种状态下的曲率... 详细信息

在平截面和平面弯曲等假设条件下,建立拼焊板V形可适于小曲率自由弯曲回弹的解析预测模型,所建立的回弹预测模型将成形过程分段研究,即区分为贴模阶段和未贴模阶段。分别根据贴模态和未贴模态拼焊板弯矩分布特点,构建两种状态下的曲率分布方程。在自由弯曲卸载分析阶段,引入两母板间相互作用的弯矩,同时考虑弹性模量随塑性变形变化的影响,基于单一母板求解拼焊板母板回弹后的弯曲角。基于2D单应矩阵变换法实现拼焊板回弹后端面弯曲角的在线测量。针对板料中材料参数的波动性问题,基于正交表构建最佳行程预测的神经网络模型的训练样本。根据软硬件接口基于LabVIEW软件平台开发可在线学习的拼焊板V形自由弯曲回弹控制系统软件。设定目标回弹后弯曲角分别为140°和100°时,跟踪在线成形试验结果,成形第5周期最大点误差可分别达到1.42%和2.01%。

关键词：拼焊板自由弯曲回弹控制

RESEARCH ON THE CHAOS DYNAMIC MODEL OF RUNOFF

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Journal of Hydrodynamics 2000年第2期12卷 85-91页

作者： Jiang, Chuanwen Quan, Xianzhang Zhang, yongchuan Hou, Zhijian Huazhong Univ of Science and Technology Wuhan China

The identification of chaos in the study of runoff serial was introduced and a dynamic model of runoff with the observed values of runoff serial was proposed. By checking the difference between the original serial and substitute serial, the nature of the runoff serial can be identified. This paper thus provides an effective method for studying the rule of runoff. The study of the chaos features of runoff and the understanding of its nonlinear dynamic model are of great significance to the understanding of the rules of runoff movement and the accurate prediction.

关键词： Chaos theory Dynamics Models Runoff

Nanofiber Composite Reinforced Organohydrogels for Multifunctional and Wearable Electronics

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Nano-Micro Letters 2023年第10期15卷 287-304页

作者： jing Wen yongchuan Wu Yuxin Gao Qin Su Yuntao Liu Haidi Wu Hechuan Zhang Zhanqi Liu Hang Yao Xuewu Huang Longcheng Tang Yongqian Shi Pingan Song Huaiguo Xue Jiefeng Gao School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002People’s Republic of China Testing Center Yangzhou UniversityYangzhou 225002People’s Republic of China Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhou 311121People’s Republic of China College of Environment and Safety Engineering Fuzhou UniversityFuzhou 350116People’s Republic of China Centre for Future Materials University of Southern QueenslandSpringfield Central 4300Australia

Composite organohydrogels have been widely used in wearable ***,it remains a great challenge to develop mechanically robust and multifunctional composite organohydrogels with good dispersion of nanofillers and strong interfacial ***,multifunctional nanofiber composite reinforced organohydrogels(NCROs)are *** NCRO with a sandwich-like structure possesses excellent multi-level interfacial ***,the synergistic strengthening and toughening mechanism at three different length scales endow the NCRO with outstanding mechanical properties with a tensile strength(up to 7.38±0.24 MPa),fracture strain(up to 941±17%),toughness(up to 31.59±1.53 MJ m~(-3))and fracture energy(up to 5.41±0.63 kJ m~(-2)).Moreover,the NCRO can be used for high performance electromagnetic interference shielding and strain sensing due to its high conductivity and excellent environmental tolerance such as anti-freezing ***,owing to the organohydrogel stabilized conductive network,the NCRO exhibits superior long-term sensing stability and durability compared to the nanofiber composite *** work provides new ideas for the design of high-strength,tough,stretchable,anti-freezing and conductive organohydrogels with potential applications in multifunctional and wearable electronics.

关键词： Composite organohydrogel Multi-level interfacial bonding Mechanical properties Strain sensor Electromagnetic interference shielding

Wavy Film Flow Along Periodic Wall Under Monochromatic-Frequency Flowrate Perturbation

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Transactions of Tianjin University 2011年第4期17卷 305-312页

作者：许松林高永川 School of Chemical Engineering and Technology Tianjin University

Surface wave dynamics of falling film on the surface of periodic rectangular wall under monochromatic-frequency flowrate forcing disturbances is studied via numerical simulation. Waveforms formed on the periodic rectangular wall are different from those on the flat plate. At low frequency, the perturbation introduced at the inlet first undergoes a steady flow region and then develops into solitary waves. When the frequency becomes higher, solitary waves disappear. Film deformations in the steady flow region and characteristics of solitary waves are studied as the film travels down. There are circulations at the depression of periodic wall which are dependent on the local film characteristics and geometry of the corrugation. Moreover, the flow rate and geometry of the corrugations can also affect the evolvement of the monochromatic perturbation.

关键词： periodic rectangular wall circulation flow solitary wave disturbance frequency film flow

Self-Navigated 3D Acoustic Tweezers in Complex Media Based on Time Reversal

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Research 2021年第1期2021卷 801-813页

作者： Ye Yang Teng Ma Sinan Li Qi Zhang Jiqing Huang Yifei Liu Jianwei Zhuang yongchuan Li Xuemin Du Lili Niu Yang Xiao Congzhi Wang Feiyan Cai Hairong Zheng Paul C.Lauterbur Research Center for Biomedical Imaging Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong ProvinceShenzhen Key Laboratory of Ultrasound Imaging and TherapyShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Shenzhen College of Advanced Technology University of the Chinese Academy of SciencesBeijing 100049China Verasonics Inc.WA 98034USA

Acoustic tweezers have great application prospects because they allow noncontact and noninvasive manipulation of microparticles in a wide range of ***,the nontransparency and heterogeneity of media in practical applications complicate particle trapping and *** this study,we designed a 1.04 MHz 256-element 2D matrix array for 3D acoustic tweezers to guide and monitor the entire process using real-time 3D ultrasonic images,thereby enabling acoustic manipulation in nontransparent ***,we successfully performed dynamic 3D manipulations on multiple microparticles using multifoci and vortex *** achieved 3D particle manipulation in heterogeneous media(through resin baffle and ex vivo macaque and human skulls)by introducing a method based on the time reversal principle to correct the phase and amplitude distortions of the acoustic *** results suggest cutting-edge applications of acoustic tweezers such as acoustical drug delivery,controlled micromachine transfer,and precise treatment.

关键词： thereby transparency precise

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川东北飞仙关组鲕滩气藏气水界面预测方法

天然气工业 2004年第8期24卷 76-77页

作者：华永川中国石油西南油气田分公司勘探事业部

气水界面的预测为早期评价气藏规模提供了依据。地震及实钻资料表明 ,川东开江—梁平海槽东北侧较大范围内飞仙关组鲕滩储层连片分布 ,以裂缝—孔隙型为主的鲕滩储层内 ,其气水分布应符合物理学中“连通管”原理。文章应用实钻正常超压 ... 详细信息

气水界面的预测为早期评价气藏规模提供了依据。地震及实钻资料表明 ,川东开江—梁平海槽东北侧较大范围内飞仙关组鲕滩储层连片分布 ,以裂缝—孔隙型为主的鲕滩储层内 ,其气水分布应符合物理学中“连通管”原理。文章应用实钻正常超压 (压力系数 1.0～ 1.2 5 )水井资料建立的压力—海拔关系方程 ,并与已获气井的气柱方程联立求解 ,可预测在钻获一口气井情况下的气水界面 ;在钻获一口水井情况下 ,应首先判定是否属“正常超压” ,若是 ,则可用超压等于地层条件下气水柱压力梯度差乘以气藏高度的原理 ,反求气藏高度 ,再配合精度较高的地震构造解释资料 ,就可推算出气水界面的海拔。

关键词：储集层气水界面四川盆地储层储集岩

Analysis of reflection coefficient for coated optical waveguide devices

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Semiconductor Photonics and Technology 1995年第1期1卷 9-19页

作者： WU Feng(Chongqing Optoelectronics Research Institute,yongchuan 632163,CHN)

From an ordinary condition,using a full three-dimensional model theory and an infinite perturbation expansion method,an exact solution of the reflection coefficient for the coated narrow stripe-geometry optical waveguide devices has been *** six components and the vector property of the electromagnetic field have been *** results are suitable for the symmetric and asymmetric waveguides.

关键词： Waveguide Theory Optical Waveguides Reflection Coefficient

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异鼠李素对乳腺癌细胞的作用机制

中国药科大学学报 2013年第6期44卷 563-567页

作者：胡珊邓甬川浙江大学医学院附属第二医院肿瘤外科杭州310009

为探讨异鼠李素对乳腺癌细胞中的作用及其机制,以两种乳腺癌细胞株MCF7和BT549作为模型细胞株,通过加入不同浓度的异鼠李素,采用MTT法检测其对细胞增殖活性的抑制作用。在确定增殖抑制作用的基础上,采用流式细胞术测定异鼠李素对细胞周... 详细信息

为探讨异鼠李素对乳腺癌细胞中的作用及其机制,以两种乳腺癌细胞株MCF7和BT549作为模型细胞株,通过加入不同浓度的异鼠李素,采用MTT法检测其对细胞增殖活性的抑制作用。在确定增殖抑制作用的基础上,采用流式细胞术测定异鼠李素对细胞周期和凋亡的影响,及采用免疫印迹的方法观察异鼠李素对细胞增殖及凋亡信号通路的影响。实验结果显示,异鼠李素可显著抑制乳腺癌细胞株MCF7及BT-549的增殖,其IC50分别为11.72和8.74μmol/L;通过流式细胞术检测,发现异鼠李素可引起细胞G1期的周期阻滞及促进细胞的凋亡,信号通路分析显示异鼠李素可减少细胞增殖通路蛋白AKT和ERK的磷酸化及增殖核抗原Ki67的表达,减少Bcl-2的表达及增加Bax的表达,促进Caspase 3的剪切,从而导致细胞的凋亡。因此,异鼠李素具有显著的抗乳腺癌作用,其作用机制与抑制细胞的增殖通路及促进细胞的凋亡有关。

关键词：异鼠李素乳腺癌增殖凋亡作用机制

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高强钢拼焊板V形模压弯曲回弹数值预测

机械工程学报 2013年第22期49卷 76-83页

作者：段永川官英平吴斌先进锻压成形技术与科学教育部重点实验室(燕山大学) 秦皇岛066004 北京工业大学机械工程与应用电子技术学院北京100022

基于ABAQUS有限元软件的UMAT和VUMAT接口,利用径向回退映射算法开发变模量的各向同性强化、线性随动强化和非线性随动强化的本构模型,耦合Aitken算法提高了非线性随动强化模型的收敛速度。利用耦合变模量的三种强化准则的模型,基于显式... 详细信息

基于ABAQUS有限元软件的UMAT和VUMAT接口,利用径向回退映射算法开发变模量的各向同性强化、线性随动强化和非线性随动强化的本构模型,耦合Aitken算法提高了非线性随动强化模型的收敛速度。利用耦合变模量的三种强化准则的模型,基于显式计算成形隐式计算回弹算法,在不同模压力和不同凸模圆角半径下对高强钢拼焊板V形模具弯曲的回弹进行预测,通过试验验证耦合应力相关变模量的非线性随动强化模型的回弹预测精度较高,最大预测误差为2.2%。应用此模型在不同凸模圆角半径和不同模压力下对高强钢拼焊板V形模具弯曲回弹后模量场和卸载后弯曲角进行预测与分析,拼焊板厚侧母板模量变化区较薄侧母板变化区域大,并在凸模圆角与直边过渡段上方出现反弯区。卸载后弯曲角随凸模圆角半径增大而增大,随着模压力的增大而减小。验证通过施加不同模压力可提高高强钢拼焊板V形模具弯曲工艺柔性的正确性,为进一步研究高强钢拼焊板V形模具弯曲自适应成形奠定基础。

关键词：拼焊板模具弯曲回弹有限元