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Synergistic Effects of Chiral Morphology and Reconfiguration in Cattail Leaves

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Journal of Bionic Engineering 2015年第4期12卷 634-642页

作者： Zilong Zhao Weixi Huang bingwei li Kexing Chen Kuifu Chen Hongping Zhao Xiqiao Feng AML Department of Engineering Mechanics Tsinghua University Beijing 100084 China Center for Nano and Micro Mechanics Tsinghua University Beijing 100084 China College of Sciences China Agricultural University Beo'ing 100083 China

Cattail, a type of herbaceous emergent aquatic macrophyte, has upright-standing leaves with a large slenderness ratio and a ehiral morphology. With the aim of understanding the effect of chiral morphology on their mechanical behavior, we investi- gated, both experimentally and theoretically, the twisting chiral morphologies and wind-adaptive reconfigurations of cattail leaves. Their multiscale structures were observed by using optical microscope and scanning electron microscopy. Their me- chanical properties were measured by uniaxial tension and three-point bending tests. By modeling a chiral leaf as a pre-twisted cantilever-free beam, fluid dynamics simulations were performed to elucidate the synergistic effects of the leaf＇s chiral mor- phology and reconfiguration in wind. It was observed that the leaves have evolved multiscale structures and superior mechanical properties, both of which feature functionally gradient variations in the height direction, to improve their ability to resist lodging failure by reducing the maximal stress. The synergistic effect ofchiral morphology and reconfiguration can greatly improve the survivability of cattail plants in wind.

关键词： cattail chiral morphology reconfiguration fluid-structure interaction lodging resistance

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen CHEN Wei CAO bingwei liU Xinhui li Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (CHP) gasification porous media combustion power generation

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中美票据权利人类型划分规则差异化研究

学术交流 2015年第2期 75-80页

作者：李兵巍黑龙江大学法学院哈尔滨150080

1996年1月1日开始施行的《中华人民共和国票据法》自颁布之日起就因存在诸多弊端饱受票据法学界的批判。在众多的修改意见中,如何修改并完善票据权利人制度少人问津,这与该制度在整个票据法体系中的重要法律地位并不相适应。在票据权利... 详细信息

1996年1月1日开始施行的《中华人民共和国票据法》自颁布之日起就因存在诸多弊端饱受票据法学界的批判。在众多的修改意见中,如何修改并完善票据权利人制度少人问津,这与该制度在整个票据法体系中的重要法律地位并不相适应。在票据权利人制度体系中,票据权利人类型划分规则是其不可或缺的一项重要组成部分。相比较而言,中美票据法在票据权利人类型划分规则方面存在体系构建、具体范畴等方面的区别,这同两国票据立法发展进程、立法技术和票据权利类型规则的差异有密切联系。中国要建立与国际接轨的、能有效推动社会经济全面发展的、先进的票据法律制度就应当改变传统法律观念,摆脱陈旧的法律思维的束缚,向英美票据法的典范——美国的票据法律制度学习;要完善票据权利人类型划分规则就要先行修改现今的票据权利类型规则。在此基础上,应当明确票据权利人包括三个类型:完全票据权利人、占有票据但是不享有票据内容权利的人和丧失票据的占有但是根据票据法享有票据权利的人。

关键词：中美票据票据权利人丧失票据的占有

Microvascular protective role of pericytes in melatonin-treated spinal cord injury in the C57BL/6 mice

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Chinese Medical Journal 2014年第15期127卷 2808-2813页

作者： Jing Yingli Wu Qingbin Yuan Xiaochen li bingwei liu Mingming Zhang Xiaoyan liu Shuying li Hongwei Xiu Ruijuan Institute of Microcirculation Key Laboratory of MicrocirculationMinistry of Health Chinese Academy of Medical Sciences &Peking Union Medical College Beijing 100005 China

Background Pericytes,located on microvessels,help to maintain vascular stability and blood-brain barrier *** influence of pericytes on microvessels after spinal cord injury （SCI） is less ***,the aim of this study was to investigate whether pericytes took a protective effect on microvessels in melatonin-treated *** C57BL/6 mice were randomly divided into three groups：sham group,SCI group,and melatonin group （n=27per group）.Functional recovery was evaluated using the Basso Mouse *** neurons were observed using hematoxylin and eosin *** coverage was analyzed using *** of blood-spinal cord barrier （BSCB） was assessed by administration of Evan＇s *** levels of occludin,aquaporin-4 （AQP4）,angiopoietin-1 （Ang1）,intercellular cell adhesion molecule-1 （ICAM-1）,Bcl-2,and Bax were determined using Western *** the pathological conditions of SCI,melatonin-treated primary pericytes were subjected to oxygenglucose deprivation/reperfusion （OGD/R）.Secretion of Ang1 was analyzed using an enzyme-linked immunosorbent assay,and the expression of ICAM-1 was detected by *** Melatonin treatment improved locomotor functional outcome and rescued motor *** coverage was significantly reduced after SCI; melatonin treatment alleviated the loss of pericyte coverage and rescued perfused microvessels 7 days after *** permeability of BSCB and loss of occludin were attenuated,and edema formation and upregulation of AQP4 were inhibited,after melatonin *** expression of Ang1 and Bcl-2 was improved,while the expression of ICAM-1 and Bax was inhibited,in melatonin-treated SCl ***,the secretion of Ang1 was increased and the expression of ICAM-1 was inhibited in melatonin-treated pericytes after OGD/*** Melatonin ameliorated the loss of blood vessels and disruption of BSCB to exert a protective effect on SCI,which might be mediate

关键词： pericyte spinal cord injury microvessel blood-spinal cord barrier angiopoietin-1 melatonin

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防渗墙钻孔压水试验渗流参数研究

岩石力学与工程学报 2016年第2期35卷 396-402页

作者：李炳蔚吴吉春南京大学地球科学与工程学院江苏南京210039 安徽水利水电职业技术学院安徽合肥230000

钻孔压水试验所得到透水率及渗透系数仅限于半无限域岩体,若条形域防渗墙钻孔压水试验仍沿用半无限域公式计算其渗流参数显然不合适。针对防渗墙几何形状和钻孔压水试验原理,在基于稳定流承压完整井的渗流场条件下,采用复变函数方法将... 详细信息

钻孔压水试验所得到透水率及渗透系数仅限于半无限域岩体,若条形域防渗墙钻孔压水试验仍沿用半无限域公式计算其渗流参数显然不合适。针对防渗墙几何形状和钻孔压水试验原理,在基于稳定流承压完整井的渗流场条件下,采用复变函数方法将条形域中井流问题变换到半无限域中,再代入直线补给边界稳定流承压完整井流公式求解,从而导出条形域防渗墙上钻孔压水试验渗流参数求解表达式。提出对条形域与半无限域流量比Q'/Q和渗透系数比k'/k进行分析,讨论防渗墙与钻孔几何尺寸L/r_0,r_0对其影响;当取L/r_0Q,q'>q,而渗透系数k'100时按提出的计算方法与芯样室内渗透试验结果基本一致。该研究方法还可将钻孔压水试验推广到其他形状有限域渗流参数求解中。

关键词：渗流力学钻孔压水试验防渗墙条形域复变函数

端接接头激光-MAG复合焊熔滴过渡与气孔特征分析

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中国激光 2019年第3期46卷 72-79页

作者：雷正龙黎炳蔚周恒何旺哈尔滨工业大学先进焊接与连接国家重点实验室黑龙江哈尔滨150001

通过端接接头的激光-MAG复合焊接实验,研究了焊接方式、光丝间距、能量输入等对熔滴过渡行为及气孔缺陷特征的影响规律。研究结果表明:激光-MAG复合焊接比单激光焊更适用于端接接头的焊接,可以改善焊缝的成形,抑制气孔缺陷;激光引导方... 详细信息

通过端接接头的激光-MAG复合焊接实验,研究了焊接方式、光丝间距、能量输入等对熔滴过渡行为及气孔缺陷特征的影响规律。研究结果表明:激光-MAG复合焊接比单激光焊更适用于端接接头的焊接,可以改善焊缝的成形,抑制气孔缺陷;激光引导方式优于电弧引导方式,得到的焊缝内的气孔缺陷较少;适当增加光丝间距有利于焊接过程的稳定性;电弧能量输入主要影响焊缝形态,而激光能量增加则会阻碍熔滴过渡,并使焊缝底部产生气孔缺陷。

关键词：激光技术激光-电弧复合焊熔滴过渡气孔缺陷

Saponifying P507-kerosine organic phase by rare earth hydroxide for lowering acid-base consumption and waste water emission

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Saponifying P507-kerosine organic phase by rare earth hydrox...

基于声振传递的飞行器噪声振动环境预示方法研究

中国稀土学会2020学术年会暨江西(赣州)稀土资源绿色开发与高效利用大会

作者： li Hongyang li Yanyang Wang Kang Zhou Huajiao li bingwei liu Yanzhu Zhou Xuezhen li Jing li Dongping li Yongxiu Institue of Rare Earths Nanchang University Zibo Baogang lingzhi Rare Earth High technology Co.Ltd

Rare earth hydroxide(REHO) obtained from the alkali conversion of rare earth phosphate and fluorocarbon minerals(REPFM) was used to saponify P507-kerosine organic phase for the counter current extraction separation of rare earths. Therefore, the dependence of the loaded concentration of rare earth in organic phase(LCREOP) and the acidity of raffinate(pHR) on the initial concentration of rare earth in aqueous phase(ICREAP), the phase ratio of organic phase to aqueous phase(R=O/A) and the stage number(SN) of counter current extraction were studied in this paper. The results showed that LCREOP increased with the decrease of R, the increase of ICREAP or SN. Accordingly, the outlet LCREOP can be easily controlled by adjusting R, ICREAP and SN, and qualified organic phases with LCREOP ranging from 0.16 to 0.24 mol/l can be obtained. Therefore, a new process consisting of a countercurrent saponification unit(CSU) for producing required P507-kerosine organic phase and a acidic raffinate recycling unit(ARRU) for dissolving REHO and obtaining required aqueous phase was developed. This process is expected to be applied in the green and low cost separation of such resources for reducing the acid-base consumption and waste water emission via the circulating utilization of acidic raffinate.

关键词： Rare earth extraction separation saponification low consumption environment friendly

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振动与冲击 2024年第1期43卷 290-296页

作者：李炳蔚朱红民刘时秀陈刚中国运载火箭技术研究院北京100076 北京强度环境研究所北京100076 北京航天长征飞行器研究所北京100076

针对高速飞行器飞行条件下的噪声、振动环境恶劣、复杂、难预示的问题,提出了基于声振传递的飞行器飞行条件下的噪声、振动环境预示方法。采用数值仿真、脉动压力风洞试验或工程分析等方法,获取飞行器在典型工况下的舱外脉动压力场;通... 详细信息

针对高速飞行器飞行条件下的噪声、振动环境恶劣、复杂、难预示的问题,提出了基于声振传递的飞行器飞行条件下的噪声、振动环境预示方法。采用数值仿真、脉动压力风洞试验或工程分析等方法,获取飞行器在典型工况下的舱外脉动压力场;通过噪声试验或声振耦合仿真分析的方法,得到飞行器声振传递特性;根据获得的舱外脉动压力和声振能量传递特性,结合具体飞行参数得到实际飞行条件下的飞行器声振预示环境。采用该方法对某飞行器开展了振动环境预示研究,经地面及飞行试验验证振动环境量级预示精度可达1.6 dB。提出的基于声振传递的飞行声振环境预示方法可以广泛应用在导弹、火箭等飞行器的精细化环境设计中,对于提高飞行器总体性能、环境适应性和飞行可靠性具有重要的工程意义。

关键词：声振传递飞行器声振环境环境预示飞行环境脉动压力

基于阻尼辨识的双层厚壁结构声振环境预示研究

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振动与冲击 2017年第21期36卷 225-231页

作者：赵长见李炳蔚张志勇牛智玲刘博航天科学与工程学院国防科技大学长沙410073 中国运载火箭技术研究院北京100076

高超声速飞行器主要舱段一般为双层厚壁结构,以满足防热和载荷需求。为了精确预示高超声速飞行器舱段结构的声振响应,开展了基于阻尼辨识的双层厚壁结构声振环境预示研究,提出了一种基于声振试验的阻尼损耗因子辨识方法,给出了基于阻尼... 详细信息

高超声速飞行器主要舱段一般为双层厚壁结构,以满足防热和载荷需求。为了精确预示高超声速飞行器舱段结构的声振响应,开展了基于阻尼辨识的双层厚壁结构声振环境预示研究,提出了一种基于声振试验的阻尼损耗因子辨识方法,给出了基于阻尼辨识数据库的声振环境预示流程。以某超高声速飞行器双层厚壁舱段为研究对象,对结构声振耦合环境进行了统计能量分析,开展了声振试验和基于试验的阻尼辨识,得到了与试验结果吻合较好的声振环境预示结果。提出的双层厚壁结构阻尼辨识方法和声振环境预示方法对于飞行器结构动力学环境精确预示具有重要意义,可以广泛应用于航天、航空、船舶和汽车等领域。

关键词：阻尼辨识双层厚壁结构声振环境环境预示