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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

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

晋西黄土区油松人工林密度和立地对细根特征的影响

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北京林业大学学报 2024年第10期46卷 22-32页

作者：卫朝阳张建军赖宗锐胡亚伟赵炯昌唐鹏王思淇北京林业大学水土保持学院山西吉县森林生态系统国家野外科学观测研究站北京林业大学水土保持国家林业局重点实验室北京林业大学林业生态工程教育部工程研究中心

[目的]探究不同林分密度、坡度和坡向条件下油松人工林细根（≤2 mm）生物量和细根形态的垂直分布规律,为晋西黄土区植被管理和生态建设评价提供依据。[方法]以油松人工林为研究对象,选择不同林分密度M1（ 5 000株/hm2）,不同坡度（≤2... 详细信息

[目的]探究不同林分密度、坡度和坡向条件下油松人工林细根（≤2 mm）生物量和细根形态的垂直分布规律,为晋西黄土区植被管理和生态建设评价提供依据。[方法]以油松人工林为研究对象,选择不同林分密度M1（ 5 000株/hm2）,不同坡度（≤20°、20°～30°、30°～40°）和坡向（阴坡和阳坡）的样地,采用根钻法分层获取0～100 cm土层中的细根,对细根生物量密度、根长密度、组织密度、比根长和比表面积的垂直分布特征及其影响因素进行研究。[结果]（1）0～100 cm土层的细根生物量密度随林分密度增大呈单峰变化趋势（M4密度条件下达到最大值606.19 g/m3）,不同坡度和坡向条件下细根生物量密度及其垂直分布没有明显变化趋势。细根生物量密度随土层深度增加呈显著递减趋势（P<0.05）,主要集中在0～20 cm土层中,占比38%以上。（2）随着林分密度增加,0～100 cm土层的细根根长密度呈单峰变化趋势（M4密度下达到最高值3 639.73 m/m2）,比根长和比表面积呈先减小后增加的趋势（在M4密度下达到最低值:比根长601 cm/g,比表面积101.09 cm2/g）。坡度和坡向对细根形态及其垂直分布的影响均不显著。垂直方向上,各林分密度0～40 cm土层的细根根长密度占比均在60%以上。在0～20 cm土层,比根长和比表面积随林分密度的增加先减少后增加（P<0.05）。（3）相关性分析显示,林分密度和土层深度对细根生物量密度和细根形态有显著影响。细根生物量密度和根长密度与林分密度、土壤全碳、全氮以及有机碳显著正相关,与土壤深度和C:N显著负相关。比根长、比表面积与林分密度和土壤有机碳显著负相关,与土壤深度显著正相关（P<0.05）。[结论]林分密度是油松人工林细根特征的关键调控因子,可通过林分管理措施来调整人工林林分密度以及细根生存策略,以此提高油松人工林应对环境胁迫的适应性,为半干旱区人工林可持续经营提供理论支持。

关键词：油松人工林细根生物量细根形态特征垂直分布影响因素

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

Detwinning and Anneal-Hardening Behaviors of Pre-Twinned AZ31 Alloys under Cryogenic Loading

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1551-1563页

作者： Lingyu Zhao wei Zhu Chao Zhang Yunchang Xin Changjian Yan Yao Cheng zhaoyang Jin School of Mechanical Engineering Yangzhou UniversityYangzhou225127China Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing210009China Institute of Corrosion Science and Technology Guangzhou510070GuangdongChina Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of TechnologyNanjing211167China

Detwinning behavior of a pre-twinned magnesium alloy AZ31 at cryogenic temperature was investigated,also with a focus on the annealing hardening behavior of samples with different fractions of ***-compression along the transverse direction with strains of 1.7%,3.0%,and 6.0% was applied to generated[1012]*** behavior,microstructure,and texture evolution during subsequent tension were *** results show that low temperature did not change the fact that detwinning still pre-dominated in the pre-twinned samples under reverse ***,a relatively harder migration of twin boundaries was found at cryogenic *** annealing hardening of 27-40 MPa was observed in the pre-twinned samples,and such a hardening effect shows a close relation with the fraction of pre-twins or the level of *** annealing hardening effect disappeared if the matrix was consumed by twins along with the increased pre-compression *** corresponding reasons for the annealing hardening behavior were discussed.

关键词： Mg alloys Detwinning Annealing hardening Cryogenic temperature Mechanical property

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

Improved Flexible Triboelectric Nanogenerator Based on Tile-Nanostructure for Wireless Human Health Monitor

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Energy & Environmental Materials 2024年第4期7卷 386-395页

作者： Huamin Chen Shujun Guo Shaochun Zhang Yu Xiao wei Yang zhaoyang Sun Xu Cai Run Fang Huining Wang Yun Xu Jun Wang Zhou Li Fujian Key Laboratory of Functional Marine Sensing Materials Minjiang University Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Institute of Semiconductors Chinese Academy of Sciences Beijing Key Laboratory of Inorganic Stretchable and Flexible Information Technology Faculty of Science and Engineering The University of Nottingham Ningbo China

Triboelectric nanogenerators (TENCs) have emerged as promising candidates for integrating with flexible electronics as self-powered systems owing to their intrinsic flexibility,biocompatibility,and *** this study,an improved flexible TENC with a tile-nanostructured MXene/polymethyl methacrylate (PMMA) composite electrode (MP-TENC) is proposed for use in wireless human health monitor.

关键词： flexible electrode MXene tile nanostructure triboelectric nanogenerator wireless monitor

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

移动新闻客户端大型体育赛事传播困境与发展策略研究

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沈阳体育学院学报 2015年第5期34卷 80-86页

作者：李芳魏朝阳沈阳体育学院体育人文学院辽宁沈阳110102 沈阳体育学院研究生部辽宁沈阳110102

运用文献资料法、专家访谈法和内容分析法,以4大门户网站移动新闻客户端2014年巴西世界杯和2015年足球亚洲杯报道为主要研究内容。通过传播现状的调查分析,得出移动新闻客户端大型体育赛事传播困境为传播主体层面——生产方式变革导致... 详细信息

运用文献资料法、专家访谈法和内容分析法,以4大门户网站移动新闻客户端2014年巴西世界杯和2015年足球亚洲杯报道为主要研究内容。通过传播现状的调查分析,得出移动新闻客户端大型体育赛事传播困境为传播主体层面——生产方式变革导致信息把关缺失;传播内容层面——意义迷误碎片切割消解体育本质;传播形式层面——社交媒体崛起引发赛事版权危机;传播受众层面——个性定制导致用户观赛视域狭窄;传播生态层面——场景依赖茧房社交弱化族群效应。并针对以上问题从建构多角色新媒体赛事监管体系、依托赛事整合资源渲染体育魅力、版权分销与自制短视频并轨行进、改变出版逻辑拓宽用户观赛视野和场景革命规避族群隐性麻醉效果等5个维度提出发展策略。

关键词：移动新闻客户端大型体育赛事传播困境发展策略