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Nano Materials Science 2022年第2期4卷 169-177页

作者： Tianqi Liang Jie Liu zhaoyang wei Dean Shi Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsHubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan430062PR China

In this study,CuO nanoparticles are pre-modified with styrene-maleic anhydride copolymers(SMAs)of different molecular weights and MAH *** the pre-modified CuO nanoparticles(CuO-SMAs)are added to the PA6/SEBS(Styrene Ethylene Butylene Styrene copolymer)(40/60 wt/wt)polymer blends with a co-continuous *** SMA3(MAH=8 wt%,M_(n)=250000 g/mol)is used to modify CuO nanoparticles,and the grafting degree of SMA3 on the surface of CuO reaches 2.74 wt%,90.71%of the added mCuO-SMA3 nanoparticles can be located at the interface of PA6 and SEBS.A porous PA6 membrane with CuO nanoparticles located at the pore walls can be obtained after the SEBS phase is etched with *** catalytic reaction velocity constant(k)for the reduction of p-nitrophenol in NaBH_(4)solutions with the PA6/mCuO-SMA3 porous membrane can reach 1.0040 min^(-1).This work provides a feasible and straightforward method for the preparation of porous polymer membranes with functional nanoparticles located at the wall of the pores.

关键词： Co-continuous CuO nanoparticles Selective distribution Porous PA6 membrane Catalytic performance

土壤含水量对探地雷达探测植物根系构型精度的影响

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干旱区研究 2024年第3期41卷 456-466页

作者：王勃张建军赖宗锐赵炯昌胡亚伟杨周李阳卫朝阳北京林业大学水土保持学院北京100083 山西吉县森林生态系统国家野外科学观测研究站山西吉县042200

根系是评价植被生态服务功能的关键基础要素,但快速、精确、无损确定根系的测量技术和方法是目前生态系统评估中的瓶颈。探地雷达是一种高效无损的地球物理学技术,可以在无损状态下获取土壤中的根系信息。但是探地雷达检测和识别根系的... 详细信息

根系是评价植被生态服务功能的关键基础要素,但快速、精确、无损确定根系的测量技术和方法是目前生态系统评估中的瓶颈。探地雷达是一种高效无损的地球物理学技术,可以在无损状态下获取土壤中的根系信息。但是探地雷达检测和识别根系的精度受土壤含水量、根系含水量、根径大小、根系埋藏深度等诸多因素影响,导致其在野外根系探测中适用性受限,为了探究土壤含水量对探地雷达探测根系精度的影响,本研究采用野外预埋根系的控制实验,根据探地雷达波速、振幅和根点反射系数的变化,分析了不同土壤含水量条件下根点识别率及根点距离均方根误差。结果表明:(1)根系探测中,探地雷达波速和振幅是判断土壤含水量变化的重要参数;(2)随着土壤含水量的增大,探地雷达波速减小,雷达振幅趋于平缓;(3)不同土层深度上随着根系直径的增大,探地雷达波速增大,雷达振幅趋于激烈;(4)根点识别率与土壤含水量成负相关(P<0.05),土壤含水量为15%~25%时探地雷达对活根的识别效果最佳。本研究表明探地雷达可以作为植物根系生物量无损和快速测定、评估的方法,但在利用探地雷达测定土壤中根系时,应在土壤含水量相对较低的时间段进行。

关键词：探地雷达根系土壤含水量无损探测晋西黄土区

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Construction of all-organic low dielectric polyimide hybrids via synergistic effect between covalent organic framework and cross-linking structure

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Nano Materials Science 2023年第4期5卷 429-438页

作者： Wanjing Zhao zhaoyang wei Chonghao Lu Yizhang Tong Jingshu Huang Xianwu Cao Dean Shi Robert KYLi wei Wu Key Laboratory of Polymer Processing Engineering of Ministry of Education Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry of Education Key Laboratory for the Green Preparation and Application of Functional MaterialsHubei Key Laboratory of Polymer MaterialsFaculty of Materials Science and EngineeringHubei UniversityWuhan430062China Department of Materials Science and Engineering City University of Hong KongTat Chee AvenueKowloonHong Kong Special Administrative Region of China Jihua Laboratory Foshan528200China

Polyimide(PI)is a promising electronic packaging material,but it remains challenging to obtain an all-organic PI hybrid film with decreased dielectric constant and loss without modifying the ***,a series of allorganic PI hybrid films were successfully prepared by introducing the covalent organic framework(COF),which could induce the formation of the cross-linking structure in the PI *** to the synergistic effects of the COF fillers and the cross-linking structure,the PI/COF hybrid film containing 2 wt%COF exhibited the lowest dielectric constant of 2.72 and the lowest dielectric loss(tanδ)of 0.0077 at 1 *** is attributed to the intrinsic low dielectric constant of COF and a large number of mesopores within the ***,the cross-linking network of PI prevents the molecular chains from stacking and improves the fraction of free volume(FFV).The molecular dynamics simulation results are well consistent with the dielectric properties ***,the PI/COF hybrid film with 5 wt%COF showed a significant enhancement in breakdown strength,which increased to 412.8 kV/mm as compared with pure *** addition,the PI/COF hybrid film achieve to reduce the dielectric constant and thermal expansion coefficient(CTE).It also exhibited excellent thermal,hydrophobicity,and mechanical *** all-organic PI/COF hybrid films have great commercial potential as next-generation electronic packaging materials.

关键词： Polyimide Covalent organic framework All-organic Cross-linking structure Dielectric property Hybrid film

Investigation of FRP and SFRC Technologies for Efficient Tunnel Reinforcement Using the Cohesive Zone Model

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Structural Durability & Health Monitoring 2024年第2期18卷 161-179页

作者： Gang Niu zhaoyang Jin wei Zhang Yiqun Huang China Communications Construction Investment Development Co. Ltd.Fuzhou350000China Rail Transit Branch of China Communications Construction Co. Ltd.Beijing101317China School of Civil Engineering Fujian University of TechnologyFuzhou350118China

Amid urbanization and the continuous expansion of transportation networks,the necessity for tunnel construction and maintenance has become *** this need requires the investigation of efficient,economical,and robust tunnel reinforcement *** paper explores fiber reinforced polymer(FRP)and steel fiber reinforced concrete(SFRC)technologies,which have emerged as viable solutions for enhancing tunnel *** is celebrated for its lightweight and high-strength attributes,effectively augmenting load-bearing capacity and seismic resistance,while SFRC’s notable crack resistance and longevity potentially enhance the performance of tunnel ***,current research predominantly focuses on experimental analysis,lacking comprehensive theoretical *** bridge this gap,the cohesive zone model(CZM),which utilizes cohesive elements to characterize the potential fracture surfaces of concrete/SFRC,the rebar-concrete interface,and the FRP-concrete interface,was employed.A modeling approach was subsequently proposed to construct a tunnel segment model reinforced with either SFRC or ***,the corresponding mixed-mode constitutive models,considering interfacial friction,were integrated into the proposed *** validation and numerical simulations corroborated the accuracy of the proposed ***,this study examined the reinforcement design of tunnel *** a numerical evaluation,the effectiveness of innovative reinforcement schemes,such as substituting concrete with SFRC and externally bonding FRP sheets,was assessed utilizing a case study from the Fuzhou Metro Shield Tunnel Construction Project.

关键词： Tunnel segment FRP SFRC cohesive zone model constitutive model fracture process

Assessment of the Influence of Tunnel Settlement on Operational Performance of Subway Vehicles

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Structural Durability & Health Monitoring 2024年第1期18卷 55-71页

作者： Gang Niu Guangwei Zhang zhaoyang Jin wei Zhang Xiang Liu China Communications Construction Rail Transit Subsidiary Beijing100000China China Communications Construction Strait Construction Investment Development Co. Ltd.Fuzhou350000China School of Civil Engineering Fujian University of TechnologyFuzhou350118China

In the realm of subway shield tunnel operations,the impact of tunnel settlement on the operational performance of subway vehicles is a crucial *** study introduces an advanced analytical model to investigate rail geometric deformations caused by settlement within a vehicle-track-tunnel coupled *** model integrates the geometric deformations of the track,attributed to settlement,as track irregularities.A novel“cyclic model”algorithm was employed to enhance computational efficiency without compromising on precision,a claim that was rigorously *** model’s capability extends to analyzing the time-history responses of vehicles traversing settlement-affected *** research primarily focuses on how settlement wavelength,amplitude,and vehicle speed influence operational *** findings indicate that an increase in settlement wavelength can improve vehicle performance,whereas a rise in amplitude can degrade *** study also establishes settlement thresholds,based on vehicle operation comfort and *** insights are pivotal for maintaining and enhancing the safety and efficiency of subway systems,providing a valuable framework for urban infrastructure management and long-term maintenance strategies in metropolitan transit systems.

关键词： Settlement running performance subway tunnel dynamic analysis track irregularity threshold

Eu-MOF-Based Fluorescent Ratiometric Sensor by Detecting 3,4,5-Trihydroxybenzoic for Fingerprint Visualization on Porous Objects

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Photonic Sensors 2024年第1期14卷 85-98页

作者： Muwen LIANG Yabin ZHAO Yaping LUO Bin DU wei HU Bing LIU Xihui MU zhaoyang TONG Department of Investigation People's Public Security University of ChinaBejing 100038China State Key Laboratory of NBC Protection for Civilian Beijing 102205China

Latent fingerprints(LFPs)at the crime scene are served as important clues to locate the trajectory of criminal behavior and portray the characteristics of the ***,visualizing LFPs is of considerable *** this work,the europium metal-organic framework(Eu-MOF)sensor was successfully constructed for sensitive detection of gallic acid(3,4,5-trihydroxybenzoic acid,GA)and visualization of the sweat *** boric-acid-modified Eu-MOF was prepared by using the simple one-pot solvothermal method using Eu as the metal i ion center and 3,5-dicarboxybenzeneboronic acid(BBDC)as the organic *** sensor showed desirable photoluminescent performance through the chelating of BBDC with Eu3+.The sensor exhibited the satisfactory linear relationship to GA in the range of 1 nM to 20 nM with a low detection limit of 0.34 nM under the optimized *** prepared sensor with ideal selectivity to GA was successfully applied for visualizing LFPs on porous substrates with the high contrast and superior *** the good performance of the sensor,all fingerprint images obtained from 1200 samples presented clear friction ridges and met the identification ***,the sensor had less impact on the subsequent deoxyribonucleic acid(DNA)detection,displaying a promising perspective for applications in extracting physical evidence of site investigation.

关键词： Europium metal-organic framework(Eu-MOF) photoluminescence 3,4,5-trihydroxybenzoic latent fingerprints(LFPs)development

Role of adhesion molecules in cancer and targeted therapy

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Science China(Life Sciences) 2024年第5期67卷 940-957页

作者： Chunmei Fan Fang Xiong Shanshan Zhang Zhaojian Gong Qianjin Liao Guiyuan Li Can Guo wei Xiong He Huang zhaoyang Zeng NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of MedicineCentral South UniversityChangsha 410000China Department of Histology and Embryology Xiangya School of MedicineCentral South UniversityChangsha410013China Department of Stomatology Xiangya HospitalCentral South UniversityChangsha 410078China Department of Oral and Maxillofacial Surgery The Second Xiangya HospitalCentral South UniversityChangsha 410011China Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education Cancer Research InstituteCentral South UniversityChangsha 410078China

Adhesion molecules mediate cell-to-cell and cell-to-extracellular matrix interactions and transmit mechanical and chemical signals among *** mechanisms deregulate adhesion molecules in cancer,enabling tumor cells to proliferate without restraint,invade through tissue boundaries,escape from immune surveillance,and survive in the tumor *** studies have revealed that adhesion molecules also drive angiogenesis,reshape metabolism,and are involved in stem cell *** this review,we summarize the functions and mechanisms of adhesion molecules in cancer and the tumor microenvironment,as well as the therapeutic strategies targeting adhesion *** studies have implications for furthering our understanding of adhesion molecules in cancer and providing a paradigm for exploring novel therapeutic approaches.

关键词： adhesion molecules tumor microenvironment invasion and metastasis reshaping metabolism angiogenesis immune evasion tumor stemness therapeutic strategy

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Theoretical analysis of frequency modulation-to-amplitude modulation on the final optics and target of the SG Ⅱ-Up laser facility

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High Power Laser Science and Engineering 2024年第1期12卷 84-98页

作者： Yujia Zhang wei Fan Jiangfeng Wang Xiaochao Wang Xinghua Lu Dajie Huang Shouying Xu Yanli Zhang Mingying Sun zhaoyang Jiao Shenlei Zhou Xiuqing Jiang Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

Frequency modulation(FM)-to-amplitude modulation(AM) conversion is an important factor that affects the time±power curve of inertial confinement fusion(ICF) high-power laser facilities. This conversion can impact uniform compression and increase the risk of damage to optics. However, the dispersive grating used in the smoothing by spectral dispersion technology will introduce a temporal delay and can spatially smooth the target. The combined effect of the dispersive grating and the focusing lens is equivalent to a Gaussian low-pass filter, which is equivalent to 8 GHz bandwidth and can reduce the intensity modulation on the target to below 5% with 0.3 nm @ 3 GHz + 20 GHz spectrum phase modulation. The results play an important role in the testing and evaluating of the FM-to-AM on the final optics and the target, which is beneficial for comprehensively evaluating the load capacity of the facility and isentropic compression experiment for ICF.

关键词： dispersion grating frequency modulation-to-amplitude modulation conversion high-power laser facility inertial confinement fusion phase modulation

基于四自由度整体控制模型的径向磁悬浮轴承预测控制

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轴承 2023年第7期 9-13页

作者：许强卫朝阳华北水利水电大学电气工程学院郑州450045

四自由度径向磁悬浮轴承系统控制复杂,且通常采取从单自由度出发设计控制器。提出了一种基于径向四自由度整体控制模型预测控制方法,由磁悬浮轴承的动力学方程得到四自由度径向轴承线性化模型,利用Simulink进行仿真并与PID控制效果进行... 详细信息

四自由度径向磁悬浮轴承系统控制复杂,且通常采取从单自由度出发设计控制器。提出了一种基于径向四自由度整体控制模型预测控制方法,由磁悬浮轴承的动力学方程得到四自由度径向轴承线性化模型,利用Simulink进行仿真并与PID控制效果进行比较。结果表明,模型预测控制的控制器设计简单,无需解耦,无论转子高速或者低速运行,均可控制系统平稳进入稳定状态,没有振荡和超调问题,比PID解耦下的控制效果更加接近实际系统。

关键词：滑动轴承磁力轴承径向轴承振动解耦自动控制位移

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基于多信息融合的自适应局部线性嵌入算法

电子测量技术 2023年第24期46卷 112-118页

作者：刘庆强魏朝阳东北石油大学电气信息工程学院大庆163318

局部线性嵌入算法LLE的降维性能与挖掘的流形结构密切相关,但LLE挖掘的流形结构单一,并且对邻域参数选取敏感,无法提取全面的流形局部结构,限制了LLE的降维性能。为此,本文提出基于多信息融合的自适应局部线性嵌入算法MIF-ALLE。MIF-ALL... 详细信息

局部线性嵌入算法LLE的降维性能与挖掘的流形结构密切相关,但LLE挖掘的流形结构单一,并且对邻域参数选取敏感,无法提取全面的流形局部结构,限制了LLE的降维性能。为此,本文提出基于多信息融合的自适应局部线性嵌入算法MIF-ALLE。MIF-ALLE首先利用切空间近似判据自适应选择邻域参数,获取更准确的局部邻域;然后,将局部邻域中蕴含的切空间角度信息与局部线性信息相融合,挖掘更全面的流形局部结构,降低局部低维嵌入的偏差;最后,在公开轴承数据集以及实验室提取的轴承数据集上进行实验验证。实验结果表明:MIF-ALLE可以挖掘更全面的流形结构,提取更显著的特征,轴承故障诊断准确率最高可达100%。

关键词：局部线性嵌入算法流形结构自适应邻域轴承故障诊断