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HIGHLY DISPERSED MULTI-WALLED CARBON NANOTUBES IN WATER/ETHANOL AND ITS APPLICATION FOR PVA COMPOSITE

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 389-396页

作者： X.Y.Tao j.M.xu F.Liu G.L.xu InstituteofMaterialsPhysicsandMicrostructures DepartmentofMaterialsScienceandEngmeeringZhejiangUniversityHangzhou310027China CollegeofElectronicInformation HangzhouDianziUniversityHangzhou310018China

Two carboxylation processes were carried out to modify multi-walled carbon nanot ube bundles (m-MWNTs). The results showed that both of the m-MWNTs could be high ly dispersed in water with the concentration up to 25 and 15mg/mL in ethanol wit hout obvious deposition or conglomeration over 6 months. FTIR, Raman, TGA and TE M characterizations of the m- MWNTs showed that hydroxyl and carboxyl groups hav e been attached with MWNTs, and that the nanotube structure was only damaged a l ittle after modification treatments in mixed acids over 24h. Above prepared nano tube suspensions in water were successfully used as a filler of thermoplastic PV A composite to enhance its electrical conductivity. The results showed that the addition of m-MWNTs greatly improved the conductivity and the threshold of mass fraction was about 5wt%. The results also proved that purification process was n ot needed because of high purity of the raw MWNTs prepared in our group.

关键词： carbon nanotube polyvinylalcohol composite conductivity

Revisiting the trail pheromone components of the red imported fire ant, Solenopsis invicta Buren

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Insect Science 2023年第1期30卷 161-172页

作者： Tian xu Nuo Zhang Meng xu Gaetan Glauser Ted C.j.Turlings Li Chen State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina School of Life Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaodingHebei ProvinceChina College of Forestry Nanjing Forestry UniversityNanjingChina School of Agriculture Yangtze UniversityJingzhouChina Neuchatel Platform of Analytical Chemistry University of NeuchatelNeuchatelSwitzerland Laboratory of Fundamental and Applied Research in Chemical Ecology University of NeuchatelSwitzerland

Ants use species-specific trail pheromones to coordinate their sophisticated foraging *** the past decades,many trail pheromone components with various structures have been identified in ants,including the red imported fire ant,Solenopsis invicta,a notorious invasive species *** compounds,Z,E-(ZEF)and E,E-α-farnesene(EEF),Z,E-(ZEHF)and E,E-α-homofarnesene(EEHF),have been reported as components of *** trail ***,another study reported an analog ofα-farnesene,Z,Z,Z-allofarnesene,as a key trail pheromone *** contrasting results caused some uncertainty about the trail pheromone composition in *** this study,we synthesized ZEF and EEF,ZEHF and EEHF,and reanalyzed the chemicals in the Dufour gland extract and in the trail pheromone fraction of *** worker body *** reported isomers of farnesene and homofarnesene were detected and showed trail-following activity,with ZEF as the major compound,while no allofarnesene was found,neither in the Dufour gland extract nor in the whole-body *** results confirm ZEF and EEF,ZEHF and EEHF as trail pheromone components of ***.

关键词： allofarnesene Dufour gland α-farnesene α-homofarnesene synthesis trail-following

Statistical moment-based structural damage detection method in time domain

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 13-23页

作者： j.Zhang Y.L.xu j.Li Y.Xia j.C.Li Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Department of Building Engineering Tongji University Faculty of Engineering University of Technology Sydney

A novel structural damage detection method with a new damage index,i.e.,the statistical moment-based damage detection（SMBDD） method in the frequency domain,has been recently *** aim of this study is to extend the SMBDD method in the frequency domain to the time domain for building structures subjected to non-Gaussian and non-stationary *** applicability and effectiveness of the SMBDD method in the time domainis verified both numerically and *** buildings with various damage scenarios are first numerically investigated in the time domain taking into account the effect of measurement *** applicability of the proposed method in the time domain to building structures subjected to non-Gaussian and non-stationary excitations is then experimentally investigated through a series of shaking table tests,in which two three-story shear building models with four damage scenarios *** identified damage locations and severities are then compared with the preset *** comparative results are found to be satisfactory,and the SMBDD method is shown to be feasible and effective for building structures subjected to non-Gaussian and non-stationary excitations.

关键词： damage detection statistical moment time domain non-Gaussian non-stationary experimental investigation

Frozen Landweber Iteration for Nonlinear Ill-Posed Problems

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 329-336页

作者： j.xu B.Han L.Li Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100080China Department of Mathematics Harbin Institute of TechnologyHarbin 150001China

In this paper we propose a modification of the Landweber iteration termed frozen Landweber iteration for nonlinear ill-posed problems. A convergence analysis for this iteration is presented. The numerical performance of this frozen Landweber iteration for a nonlinear Hammerstein integral equation is compared with that of the Landweber iteration. We obtain a shorter running time of the frozen Landweber iteration based on the same convergence accuracy.

关键词： Ill-posed problem regularization Landweber iteration

破局与重构:基于数智赋能的大学校园书店构建策略研究

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大学图书情报学刊 2025年第1期43卷 58-65页

作者：和旭蚌埠医科大学图书馆 233030

数据驱动和智慧化环境下,用户的需求被不断释放,数智赋能已成为各行各业转型升级的关键驱动力,校园书店的建设发展亦被数智赋予更高的智慧、更强的动能。文章通过分析图书馆参与构建校园实体书店建设过程中的成效与不足,探讨基于数智赋... 详细信息

数据驱动和智慧化环境下,用户的需求被不断释放,数智赋能已成为各行各业转型升级的关键驱动力,校园书店的建设发展亦被数智赋予更高的智慧、更强的动能。文章通过分析图书馆参与构建校园实体书店建设过程中的成效与不足,探讨基于数智赋能的大学校园书店的构建路径、价值以及优化策略,以期为校园书店创新重构提供参考与借鉴。

关键词：数智化图书馆校园书店服务创新数智赋能

Probabilistic description of extreme oscillations and reliability analysis in rolling motion under stochastic excitation

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Science China(Technological Sciences) 2023年第9期66卷 2586-2596页

作者： ZHAO Dan LI YongGe xu Yong LIU Qi KURTHS jürgen School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710072China MOE Key Laboratory for Complexity Science in Aerospace Northwestern Polytechnical UniversityXi’an 710072China Potsdam Institute for Climate Impact Research Potsdam 14412Germany Department of Physics Humboldt University BerlinBerlin 12489Germany

Large-amplitude rolling motions, also regarded as extreme oscillations, are a great threat to marine navigation, which may lead to capsizing in ship motion. Therefore, it is important to quantify extreme oscillations, assess reliability of ship systems, and establish a suitable indicator to characterize extreme oscillations in ship systems. In this work, extreme events are investigated in a ship model considering a complex ocean environment, described by a single-degree-of-freedom nonlinear system with stochastic harmonic excitation and colored Gaussian noise. The stationary probability density function(PDF) of the system is derived through a probabilistic decomposition-synthesis method. Based on this, we infer the classical damage rate of the system. Furthermore, a new indicator, independent of the PDF, is proposed to quantify the damage related only to the fourth-order moment of the system and the threshold for extreme events. It is more universal and easier to determine as compared with the classical damage rate. A large damping ratio, a large noise intensity, or a short correlation time can reduce the damage rate and the value of the *** findings provide new insights and theoretical guidance to avoid extreme oscillations and assess the reliability of practical ship movements.

关键词： rolling motion colored noise extreme oscillations reliability probabilistic decomposition-synthesis method

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植被混凝土不同磷石膏掺量对狗牙根根系特性及抗拔力学性能的影响

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三峡大学学报（自然科学版） 2025年第1期47卷 65-72页

作者：杨嘉槊吴彬康柔嘉许亚坤许文年三峡大学土木与建筑学院湖北宜昌443002 水泥基生态修复技术湖北省工程研究中心(三峡大学) 湖北宜昌443002 三峡大学水利与环境学院湖北宜昌443002 三峡大学生物与制药学院湖北宜昌443002

为研究植被混凝土磷石膏含量对基材理化性质、植物根系性征及整株抗拔力的影响,进行了不同磷石膏掺量(0%、3%、4.5%、6%、9%)以及不同生长期(90、120、150d)条件下,基材相关理化指标的测定、狗牙根根系监测和原位整株拉拔试验.结果表明... 详细信息

为研究植被混凝土磷石膏含量对基材理化性质、植物根系性征及整株抗拔力的影响,进行了不同磷石膏掺量(0%、3%、4.5%、6%、9%)以及不同生长期(90、120、150d)条件下,基材相关理化指标的测定、狗牙根根系监测和原位整株拉拔试验.结果表明:磷石膏对基材容重、pH值和土壤磷含量具有显著影响;狗牙根根系网状结构显著增强了抗拔力,整株抗拔力随根系性状的改善而增大,3%掺量下抗拔力120d时高出0%掺量30.25%;适量磷石膏掺入显著促进了根系生长,3%掺量下根系总根长、根体积和根系生物量增加显著,此种情况下狗牙根根系固土效果最好.

关键词：植被混凝土磷石膏根系形态抗拔力

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智能汽车横纵向控制研究综述

汽车文摘 2025年第1期 1-7页

作者：徐伟瑞重庆交通大学机电与车辆工程学院重庆400074

智能汽车作为汽车产业和全球智能化的关键一环,在整个智能化系统中扮演着至关重要的角色。为了探索智能汽车实现自动驾驶的关键技术,研究车辆的横向和纵向控制方法,利用车辆的运动学、动力学模型及轮胎模型,分析智能车辆的横向控制和纵... 详细信息

智能汽车作为汽车产业和全球智能化的关键一环,在整个智能化系统中扮演着至关重要的角色。为了探索智能汽车实现自动驾驶的关键技术,研究车辆的横向和纵向控制方法,利用车辆的运动学、动力学模型及轮胎模型,分析智能车辆的横向控制和纵向控制,采取解耦策略简化控制难度,确保车辆按照预定路径安全行驶。为确保车辆在运动时的稳定性,加强对车辆纵向控制的研究,以优化汽车速度管理。研究了车辆的耦合控制,以克服车辆耦合效应带来的问题,优化横向和纵向控制的精确度。总结了各种相关控制算法的优缺点,并提出了智能车辆横向和纵向控制的未来发展方向,包括:深化横向控制算法研究以提升安全性;优化纵向控制以确保运动稳定性;提升耦合控制精度以增强整体控制效果。

关键词：智能汽车车辆模型横纵向控制控制算法

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大跨度钢桁梁拱桥柔性拱整体提升施工关键技术

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国防交通工程与技术 2025年第1期23卷 86-91页

作者：许君辉渝万铁路有限责任公司重庆400037

清水坪乌江大桥主跨为240 m的下承式钢桁梁柔性拱桥,拱肋结构跨度大、自重大、施工复杂。主拱肋采用“两端原位拼装+中间段先卧拼后整体提升”的施工方案,整体提升过程中设置水平索以控制主拱肋受力和变形,根据施工阶段的实际受力需求... 详细信息

清水坪乌江大桥主跨为240 m的下承式钢桁梁柔性拱桥,拱肋结构跨度大、自重大、施工复杂。主拱肋采用“两端原位拼装+中间段先卧拼后整体提升”的施工方案,整体提升过程中设置水平索以控制主拱肋受力和变形,根据施工阶段的实际受力需求采取多工况提吊及水平张拉方法;具体介绍了拼装支架的布置和提升支架的结构。使用有限元分析软件进行模拟分析,保证了整体受力的安全性和抗风稳定性。施工中采用计算机控制液压同步提升技术,高效、经济、顺利的完成主拱肋架设工作。

关键词：钢桁梁-拱柔性拱主拱肋整体提升拼装支架有限元分析抗倾覆