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Simulation of 3D parachute fluid–structure interaction based on nonlinear finite element method and preconditioning finite volume method

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Chinese Journal of Aeronautics 2014年第6期27卷 1373-1383页

作者： fan yuxin Xia Jian College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

A fluid–structure interaction method combining a nonlinear finite element algorithm with a preconditioning finite volume method is proposed in this paper to simulate parachute transient dynamics. This method uses a three-dimensional membrane–cable fabric model to represent a parachute system at a highly folded configuration. The large shape change during parachute inflation is computed by the nonlinear Newton–Raphson iteration and the linear system equation is solved by the generalized minimal residual（GMRES） method. A membrane wrinkling algorithm is also utilized to evaluate the special uniaxial tension state of membrane elements on the parachute canopy. In order to avoid large time expenses during structural nonlinear iteration, the implicit Hilber–Hughes–Taylor（HHT） time integration method is employed. For the fluid dynamic simulations, the Roe and HLLC（Harten–Lax–van Leer contact） scheme has been modified and extended to compute flow problems at all speeds. The lower–upper symmetric Gauss–Seidel（LUSGS） approximate factorization is applied to accelerate the numerical convergence speed. Finally,the test model of a highly folded C-9 parachute is simulated at a prescribed speed and the results show similar characteristics compared with experimental results and previous literature.

关键词： Flow fields analysis Fluid–structure interaction Nonlinear structural dynam-ics Numerical analysis Parachute inflation

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生物基导电水凝胶及其在柔性电子器件的应用

复合材料学报 2025年第1期42卷 104-118页

作者：董昊范雨薪张旭韦会鸽徐一飞曾威天津科技大学化工与材料学院天津科技大学生物源纤维制造技术国家重点实验室天津市贰拾壹站检测技术有限公司

生物基导电水凝胶是将生物质材料和导电介质引入水凝胶中制备而成的导电材料，因其具有良好的生物相容性和亲肤性等优势，被广泛应用在柔性电子器件领域。本综述按照生物基体类别，分别介绍蛋白质基、多糖基、核酸基3类常见的生物基导... 详细信息

生物基导电水凝胶是将生物质材料和导电介质引入水凝胶中制备而成的导电材料，因其具有良好的生物相容性和亲肤性等优势，被广泛应用在柔性电子器件领域。本综述按照生物基体类别，分别介绍蛋白质基、多糖基、核酸基3类常见的生物基导电水凝胶，分析了不同生物基材料的导电机制以及各自特有的功能，并介绍了生物基导电水凝胶在柔性传感器、柔性电化学储能器件、摩擦纳米发电机、仿生柔性电子设备等柔性电子器件中的应用，最后对生物基导电水凝胶的发展趋势进行了总结与展望。

关键词：生物基材料导电水凝胶柔性传感器柔性电化学储能器件摩擦纳米发电机仿生柔性电子设备

Numerical Simulation of ATPS Parachute Transient Dynamics Using Fluid-Structure Interaction Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第5期34卷 535-542页

作者： fan yuxin Xia Jian College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

In order to simulate and analyze the dynamic characteristics of the parachute from advanced tactical parachute system(ATPS),a nonlinear finite element algorithm and a preconditioning finite volume method are employed and developed to construct three dimensional parachute fluid-structure interaction(FSI)*** fabric material is represented by membrane-cable elements,and geometrical nonlinear algorithm is employed with wrinkling technique embedded to simulate the large deformations of parachute structure by applying the NewtonRaphson iteration *** the other hand,the time-dependent flow surrounding parachute canopy is simulated using preconditioned lower-upper symmetric Gauss-Seidel(LU-SGS)*** pseudo solid dynamic mesh algorithm is employed to update the flow-field mesh based on the complex and arbitrary motion of parachute *** to the large amount of computation during the FSI simulation,massage passing interface(MPI)parallel computation technique is used for all those three modules to improve the performance of the FSI *** FSI method is tested to simulate one kind of ATPS parachutes to predict the parachute configuration and anticipate the parachute descent *** comparison of results between the proposed method and those in literatures demonstrates the method to be a useful tool for parachute designers.

关键词： parachute dynamics fluid-structure interaction nonlinear structure dynamics time dependent flow parallel computation technique

基于风热耦合的地下空间自然通风理论计算模型及应用

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暖通空调 2025年第2期55卷 72-79,50页

作者：苏晗辰高乃平樊昱昕同济大学上海上海城投污水处理有限公司泰和污水处理厂上海

构建了一个包含捕风塔、地下空间和太阳能烟囱3个区域的自然通风系统通风流量理论预测模型,该模型阐明了室外环境参数(风速、太阳辐照度等)、建筑结构参数与系统诱导流量之间的关系。通过模型分析推导得到了临界弗劳德数,可用于判定系... 详细信息

构建了一个包含捕风塔、地下空间和太阳能烟囱3个区域的自然通风系统通风流量理论预测模型,该模型阐明了室外环境参数(风速、太阳辐照度等)、建筑结构参数与系统诱导流量之间的关系。通过模型分析推导得到了临界弗劳德数,可用于判定系统的通风模式(热压主导、热压和风压共同作用、风压主导)。利用理论模型对一个配置有捕风塔和太阳能烟囱的地下空间所构成的自然通风系统进行了通风性能评估。该模型为地下建筑自然通风设计提供了一种快速评估方法。

关键词：地下空间自然通风捕风塔太阳能烟囱热压风压临界弗劳德数理论模型

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Formation of present desert landscape surrounding Jilantai Salt Lake in northern China based on OSL dating

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Frontiers of Earth Science 2015年第3期9卷 497-508页

作者： yuxin fan Xiaolong CHEN Wenhao LIU Fu ZHANG fan ZHANG School of Earth Sciences and Key Laboratory of Mineral Resources in Western China of Gansu Province Lanzhou University Lanzhou 730000 China MOE Key Laboratory of Western China's Environmental Systems Collaborative Innovation Center for Arid Environments and Climate Change Lanzhou University Lanzhou 730000 China

The Jilantai Salt Lake （JSL）, a lake of importance due to its salt production in China since the early Qing dynasty, is surrounded by sand dunes. Exploration of the development of these sand dunes will be helpful for identifying the forces underlying the desert landscape and for identifying a solution to protect the salt resources. Through field investigation, we found sand dunes overlying either lacustrine and bog deposits on the lake bed at a lower altitude or littoral sediments on the higher lakeshores. Optically Stimulated Luminescence （OSL） dating results indicate that sands started to accumulate around the JSL as early as the early Holocene （around 11 ka）, while the rapid development of sand dunes occurred within the latest 0.1 ka. By comparison with climatic documents and human activities in adjacent regions, the initiation of sand accumulation around the JSL as early as the early Holocene is considered to be the result of low effective moisture in the Jilantai area. However, the rapid development of the sand dunes in the vast area surrounding the JSL was likely initiated by the intensified human activities which occurred within the latest 0.1 ka under warm and dry climatic conditions.

关键词： aeolian sand accumulation Jilantai Salt Lake,OSL dating

Sedimentary documents and Optically Stimulated Luminescence (OSL) dating for formation of the present landform of the northern Ulan Buh Desert,northern China

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Science China Earth Sciences 2010年第11期53卷 1675-1682页

作者： fan yuxin Chen FaHu fan TianLai Zhao Hui Yang LiPing Lanzhou Univ MOE Key Lab Western Chinas Environm Syst Lanzhou 730000 Peoples R China Lanzhou Univ Coll Earth & Environm Sci Lanzhou 730000 Peoples R China Chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China

GPR reflecting sections and core profiles revealed that sand dunes of the northern Ulan Buh Desert are overlying shallow lacustrine or palustrine sediments. Optical dating results of sediments from three core profiles indicate that the area of the northern Ulan Buh Desert was still covered by the shallow lake or marsh during 8.4-6.4 ka, and eolian sand started to accumulate since around 2 ka. Such a result supports the idea that the present desert landform of the northern Ulan Buh Desert started to form since 2 ka, which was likely a response to the desertification caused by ruin of the Han Dynasty and the large-scale abandonment of farming of the Han nationality. Our research results are consistent with the previous archaeological studies, and support the idea that the Ulan Buh Desert is composed of two parts with different histories, i.e., the old southern Ulan Buh Desert and the young northern Ulan Buh Desert.

关键词： Ulan Buh Desert landform formation OSL dating

Sedimentary and OSL dating evidence for the development of the present Hobq desert landscape, northern China

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Science China Earth Sciences 2013年第12期56卷 2037-2044页

作者： fan yuxin CHEN XiaoLong fan TianLai JIN Ming LIU JianBao CHEN FaHu Key Laboratory of Western China's Environmental Systems (MOE) Lanzhou University School of Earth Sciences & Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University

The sedimentary sequence and landscape of the Hobq desert was observed through twelve profiles along five N-S sections extending through the entire *** sands were found to overlie the alluvial,diluvial,and lacustrine sediments in this *** stimulated luminescence(OSL)dating results were obtained from post-IR OSL signals of quartz fractions of sand samples at the bottom of sand dunes and hills by using the Double-SAR *** OSL ages reveal that the latest sand accumulation began around 19 ka in the northwestern part and 9 ka in the eastern part of the Hobq *** 7 ka,the sand accumulation was strengthened and extended southward and northward 2 ka to develop the present desert *** study suggests that the aeolian sand accumulation around 19,9 and 7 ka resulted from the weakening of the Asian summer monsoon over this ***,the rapid development of the present Hobq desert landscape since 2 ka was likely triggered by human activities in this desert.

关键词： Hobq Desert OSL dating Last Glacial Maximum Holocene environmental and climatic change

Virus-induced gene silencing(VIGS)in Chinese narcissus and its use in functional analysis of NtMYB3

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Horticultural Plant Journal 2021年第6期7卷 565-572页

作者： Ping Zhou Jiayu Peng Minjie Zeng Lixuan Wu yuxin fan Lihui Zeng College of Horticulture Fujian Agriculture and Forestry UniversityFuzhou 35002China College of Horticulture Nanjing Agriculture UniversityNanjing 210095China

Virus-induced gene silencing(VIGS)is a natural defense mechanism of plants,which can cause sequence-specific degradation of viral RNA and is often used for studying the functional *** present,the VIGS system mediated by Tobacco rattle virus(TRV)has been successfully established in many plant ***,the VIGS system in Chinese narcissus had not been reported *** this paper,the first use of the TRV-VIGS system in Chinese narcissus is described in *** injecting pTRV2-GFP into narcissus leaves,we confirmed that TRV could infect narcissus and move in narcissus *** the inoculation of pTRV2-Nt PDS by two methods,phenomena such as photo-bleaching appeared in narcissus leaves and qRT-PCR results proved that PDS gene of narcissus was successfully ***,pTRV2-NtMYB3 was inoculated into basal plates of narcissus to study the function of NtMYB3;the results showed that NtMYB3 is an inhibitor of flavonoids biosynthesis,which can increase the content of proanthocyanidins in basal plates of narcissus by repressing the expression level of *** results indicate that the TRV-VIGS system has been successfully established in Chinese narcissus and successfully applied to the functional study of NtMYB3.

关键词： Chinese narcissus VIGS Tobacco rattle virus(TRV) NtPDS NtMYB3

Synergy of in-situ heterogeneous interphases tailored lithium deposition

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Nano Research 2023年第6期16卷 8304-8312页

作者： Yinuo Li Anjun Hu Xingdong Gan Miao He Jun Zhu Wei Chen Yin Hu Tianyu Lei Fei Li Yaoyao Li yuxin fan fan Wang Mingjie Zhou An Wen Baihai Li School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China

The implementation of a robust artificial solid electrolyte interphase(ASEI)to replace the unstable natural SEI can regulate lithium deposition behaviors and avoid the safety hazards caused by dendrites permeation in lithium metal *** of devoted efforts in tailoring components of ASEI,the intrinsic mechanism of interfacial synergy within the heterogeneous interphases has not been well elucidated ***,we show that the lithium plating/striping behaviors can be substantially enhanced(over 900 h with an overpotential of less than 20 mV at 1 mA·cm^(−2)in Li|Li symmetric cells and 146 cycles in anode-free cells)by regulating the heterogeneous *** favorable ASEI composed of LiF and Li_(3)N components can be in-situ generated during cycling by large-scale fabricated fluorinated boron nitride ***,the synergy of each heterogeneous component within ASEI was explored theoretically and ***_(3)N has high adsorption energy and low ion diffusion barrier,which facilitates the transport of lithium ions and avoids its local accumulation to evolve into *** the substrate and LiF are interfacially stable with high electron tunneling barriers,preventing the electrolyte decomposition and parasitic ***,the high stiffness of the boron nitride also ensures lithium dendrites are suppressed once they grow,providing a stable environment for long-term cycling of lithium metal batteries.

关键词： in-situ heterogeneous solid electrolyte interphase(SEI) lithium deposition dendrite-free first-principles calculations