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Self-nucleation Effect of Crystallization with Various Nucleating Agents

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Chinese Journal of Polymer Science 2023年第12期41卷 1912-1920,I0009页

作者： Dai Zhang rui-jun zhao Gui-Qiu Ma Zhe Ma Tianjin Key Laboratory of Composite and Functional Materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

In this work,the self-nucleation effect on crystallization was studied for polypropylene with various nucleating *** talc was employed to accelerate crystallization of monoclinic α-crystallites,while N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide TMB-5 was used to accelerate the crystallization kinetics and also induce formation of trigonal β-*** induce self-nucleation effect,the occurrence criterion was assessed by the transition temperatures from various domains and the available temperature *** importantly,the resulting influences of self-nucleation effect were quantified by the change of crystallization kinetics and the potential polymorphism *** was found that the α-nucleating agents of talc broadened the temperature window for inducing Domain Ⅱ by elevating the transition temperature from Domain Ⅰ to Domain Ⅱ.Although β-nucleating agent(β-NA)of N,N′-dicyclohexyl-2,6-naphthalenedicarboxamide TMB-5 elevated cooling crystallization temperature obviously,the temperature window for Domain Ⅱ was *** should be emphasized that in presence of β-NA TMB-5,the self-nucleation effect enhances the crystallization of α-crystallite,which show the competition with β-NA *** last,the ternary PP/talc/TMB-5 blend was prepared with the same amounts of α-NA talc and β-NA TMB-5 and it exhibits a similar self-nucleation effect of crystallization,indicating the dominant role of β-NA TMB-5.

关键词： Crystallization Kinetic Polymorphism

Memory Effect of Crystallization in 1-Butene/α-olefin Copolymers

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Chinese Journal of Polymer Science 2022年第6期40卷 576-583页

作者： Chun-Jing Qv Wei Li rui-jun zhao Zhe Ma Tianjin Key Laboratory of Composite and Functional Materials and School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

The macromolecular architecture is the crucial factor in determining the arrangement of the ordering structures,which,because of the multiscale feature,may exhibit distinct melting behaviors and induce the so-called memory effect to affect the following *** present,the correlation between the occurrence of memory effect and the intrinsic molecular structure is still far from the comprehensive *** this work,four kinds of 1-butene/α-olefin random copolymers were designed and synthesized using the(pyridyl-amino)hafnium catalyst to introduce the different *** branch length was precisely controlled by the specific α-olefin comonomers,which include 1-hexene,1-decene,1-tetradecene,and 1-octadecene,while the branch density was tuned by the *** expected,the incorporation of α-olefin co-units to poly(1-butene)backbone decreases the non-isothermal crystallization kinetics and the degree of *** interestingly,the resulting linear branch can induce the occurrence of memory effect and the threshold concentration of co-units(i.e.,branch density)decreases with increasing the branch *** on the results of these 1-butene/α-olefin copolymers with designable branches,a direct correlation with the occurrence of memory effect and the fraction of amorphous region was established,which quantitatively indicates the degree of local segregation of the crystallized poly(1-butene)sequences by theα-olefin co-units.

关键词： Memory effect 1-Butene/α-olefin copolymer Linear branch Crystallinity

Non-fragile hybrid guaranteed cost control for a class of uncertain switched linear systems

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控制理论与应用（英文版） 2006年第1期4卷 32-37页

作者： rui WANG jun zhao School of Information Science and Engineering Northeastern University Shenyang Liaoning 110004 China

This paper focuses on the problem of non-fragile hybrid guaranteed cost control for a class of uncertain switched linear systems. The controller gain to be designed is assumed to have additive gain variations. Based on multiple-Lyapunov function technique, the design of non-fragile hybrid guaranteed cost controllers is derived to make the corresponding closed-loop system asymptotically stable for all admissible uncertainties. Furthermore, a convex optimization approach with LMIs constraints is introduced to select the optimal non-fragile guaranteed cost controllers. Finally, a simulation example illustrates the effectiveness of the proposed approach.

关键词： Switched systems Guaranteed cost control Non-fragile control Multiple-Lyapunov function

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连柱钢框架体系子结构的抗震性能有限元分析

工程抗震与加固改造 2017年第4期39卷 65-73页

作者：芮俊雄赵宝成苏州科技大学江苏省结构工程重点实验室江苏苏州215011

连柱钢框架体系是一种双重抗侧力无支撑框架结构。为了研究连柱钢框架体系的抗震性能,本文设计了3组共12个子结构试件,利用有限元软件ABAQUS建立非线性有限元模型,分析子结构在循环荷载作用下的破坏模式、滞回性能、刚度退化和能量耗散... 详细信息

连柱钢框架体系是一种双重抗侧力无支撑框架结构。为了研究连柱钢框架体系的抗震性能,本文设计了3组共12个子结构试件,利用有限元软件ABAQUS建立非线性有限元模型,分析子结构在循环荷载作用下的破坏模式、滞回性能、刚度退化和能量耗散系数等参数。研究结果表明:连柱钢框架体系具有良好的屈服时序和耗能能力,塑性变形主要集中在框架梁端部和耗能连梁上;耗能连梁的长度、结构的跨度对结构的水平承载能力、刚度的影响较小;结构的层高对结构的刚度、水平承载能力的影响比较显著。在层间位移角达到1/25rad之前,连柱部分起主要耗能作用,有效地保护了承重构件。

关键词：连柱钢框架耗能连梁子结构能量耗散系数

LiDAR-Visual SLAM with Integrated Semantic and Texture Information for Enhanced Ecological Monitoring Vehicle Localization

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Computers, Materials & Continua 2025年第1期82卷 1401-1416页

作者： Yiqing Lu Liutao zhao Qiankun zhao Foreign Environmental Cooperation Center Ministry of Ecology and Environment of PRCBeijing100035China Beijing Computing Center Co. Ltd.Beijing Academy of Science and TechnologyBeijing100083China Beijing Guyu Interactive Artificial Intelligence Application Co. Ltd.Beijing100024China

Ecological monitoring vehicles are equipped with a range of sensors and monitoring devices designed to gather data on ecological and environmental *** vehicles are crucial in various fields,including environmental science research,ecological and environmental monitoring projects,disaster response,and emergency management.A key method employed in these vehicles for achieving high-precision positioning is LiDAR(lightlaser detection and ranging)-Visual Simultaneous Localization and Mapping(SLAM).However,maintaining highprecision localization in complex scenarios,such as degraded environments or when dynamic objects are present,remains a significant *** address this issue,we integrate both semantic and texture information from LiDAR and cameras to enhance the robustness and efficiency of data ***,semantic information simplifies the modeling of scene elements,reducing the reliance on dense point clouds,which can be less ***,visual texture information complements LiDAR-Visual localization by providing additional contextual *** incorporating semantic and texture details frompaired images and point clouds,we significantly improve the quality of data association,thereby increasing the success rate of *** approach not only enhances the operational capabilities of ecological monitoring vehicles in complex environments but also contributes to improving the overall efficiency and effectiveness of ecological monitoring and environmental protection efforts.

关键词： LiDAR-Visual simultaneous localization and mapping integrated semantic texture information

Leader-follower: Human-centered intention-guided controller for novel SuperLimb with application to load-carrying scenarios

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Science China Technological Sciences 2025年第1期 325-338页

作者： Qinghua ZHANG Xianglong LI Hongwei JING Kerui SUN Yuancheng LI Sikai zhao Lele LI Haotian JU Ziqi WANG rui WU Tianjiao ZHENG Jie zhao Yanhe ZHU The State Key Laboratory of Robotics and System Harbin Institute of Technology The Learning Algorithms and Systems Laboratory School of Engineeringécole Polytechnique Fédérale de Lausanne

Supernumerary robotic arms(SuperLimb) are a new type of wearable robot that works closely with humans as a third hand to augment human operation capability. Accurate conveyance of wearers' intentions, allocation of roles, and humancentered interaction considerations are the key points in the process of human–SuperLimb collaboration. This paper proposes a human-centered intention-guided leader–follower controller that relies on the dynamic modeling of SuperLimb with application to load-carrying scenarios. The proposed leader–follower controller takes the human as the leader and the SuperLimb as the follower, achieving effective information communication, autonomous coordination, and good force compliance between SuperLimb, humans, and the environment under human safety assurance. First, the human–SuperLimb dynamic system is modeled to achieve force interaction with the environment and wearer. Second, to achieve the precise intention extraction of humans, pose data from five visual odometry sensors are fused to capture the human state, the generalized position, the velocity of hands, and the surface electromyography signals from two myoelectric bracelets sensors are processed to recognize the natural hand gestures during load-carrying scenarios by a designed Swin transformer network. Then, based on the real-time distance detection between human and mechanical limbs, the security assurance and force-compliant interaction of the human–SuperLimb system are realized. Finally, the human hand muscle intention recognition, human–robot safety strategy verification,and comparative load-carrying experiments with and without the proposed method are conducted on the SuperLimb *** showed that the task parameters are well estimated to produce more reasonable planning trajectories, and SuperLimb could well understand the wearer's intentions to switch different SuperLimb actions. The proposed sensor-based human–robot communication framework motivates future studies of o

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Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： zhao-jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-Cheng Li De-Cheng Cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

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基于随机森林模型的城市空气质量评价

计算机工程与设计 2017年第11期38卷 3151-3156页

作者：杨瑞君赵楠凡耀峰侯梅芳上海应用技术大学计算机科学与信息工程学院上海201418 上海应用技术大学生态技术与工程学院上海201418

为使城市环境空气质量评价方法具有更高的准确性和鲁棒性,提出将随机森林模型引入城市环境空气质量评价中的方法。通过对随机森林模型进行训练,建立起空气质量评价因子与空气质量等级之间的内在映射关系。基于随机森林模型的评价方法,... 详细信息

为使城市环境空气质量评价方法具有更高的准确性和鲁棒性,提出将随机森林模型引入城市环境空气质量评价中的方法。通过对随机森林模型进行训练,建立起空气质量评价因子与空气质量等级之间的内在映射关系。基于随机森林模型的评价方法,对上海市空气质量数据进行评价实验,实验结果表明,评价预测平均准确性稳定在99.06%,当树数目为16个时,效果最好,准确性可达99.69%。实例验证了该方法的可行性。

关键词：随机森林模型空气质量评价分类泛化误差空气质量指数

Reverse modulation of defect density of Ce-MOF-808 by solventassisted ligand exchange for dicyclopentadiene hydrogenation

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Science China Chemistry 2025年

作者： Danfeng zhao Fajie Hu Rushuo Li Xinmeng Xu zhaokun Wang Zuoshuai Xi jun Tong Xiubing Huang Ge Wang Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing

Defect engineering is a pivotal strategy for tailoring the electronic structure and physicochemical properties of catalysts, yet the straightforward manipulation of defect density in porous materials presents a current challenge. In this work, we achieved precise control over the coordination unsaturated site（CUS） content and pore architecture of Ce-MOF-808 by employing 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p Kadisparities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we preserved the spn topology of Ce-MOF within an aqueous system, while realizing partial substitution of the auxiliary ligands and saturation of the CUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in Ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic performance of dicyclopentadiene（DCPD） hydrogenation reaction, in which Ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an optimal ligand defect density and micro-mesoporous structure, enabling almost complete conversion of DCPD at 100 ℃ and 2 MPa. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis pair（FLP） active sites, guiding the application of novel porous intrinsic FLP materials in hydrogenation catalysis.

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