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Effect of Microdomain Structure on the Mechanical Behavior of Binary Blends

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Chinese Journal of Polymer Science 2015年第7期33卷 964-975页

作者： Bin Su yong-sheng zhao 陈枫傅强 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

The relationship between microphase structure and mechanical response of the binary blends consisting of polystyrene-block-polyisoprene-block-polystyrene copolymer and low molecular weight polystyrene has been investigated. Low molecular weight polystyrene was chosen to obtain uniformly solubilized nano-blends without macrophase separation. The specimens were solution-cast by adding different amounts of homo-polystyrene to acquire different microphase structures. Small angle X-ray scattering（SAXS）, transmission electron microscopy（TEM） and atom force microscopy（AFM） have been used to study the microdomain and grain structure. It is observed that the structural changes in d-spacing and grain size on account of different amounts of polystyrene alter the mechanical behavior in both monotonic tensile and cyclic tests. The elastic and the Mullins effects are strongly sensitive to the changes in d-spacing and grain sizes. Moreover, the sample with bi-continuous structure shows the largest tensile strength and Mullins effect. In addition, the Mooneye-Rivlin phenomenological model was used to evaluate and explore the relationship between the polymer topological networks and the rubber elasticity of these styrenic nano-blends.

关键词： Microphase Grain size d-Spacing Bi-continuous structure Elastic response

The effect of metal ions with different valences on the retardation of soil–bentonite barrier materials and its mechanism

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Chinese Chemical Letters 2013年第12期24卷 1075-1079页

作者： Shu-Qing Lv yong-sheng zhao Key Laboratory of Groundwater Resources and Environment Ministry of Education Jilin University

In this paper, with K＋, Ca2＋ and Fe3＋ as the objects of study, retardation of soil-bentonite （SB） barrier materials for metal ions with different valences is investigated, and the adsorption mechanism, migration patterns and permeation behavior are explored so as to provide a theoretical basis for their application. The results show that the adsorption process for metal ions with different valences by SB barrier materials is fast, and the higher the valence, the greater the adsorption capacity. The fitting of the adsorption process conforms to pseudo-second-order adsorption kinetics and Langmuir-Freundlich adsorption equation, which explains that chemical adsorption is the dominating state and that the SB surface has certain heterogeneity. The permeability coefficient of K＋, Ca2＋ and Fe3＋ in SB each has a maximum and the higher the valence, the sooner the maximum appears. Also the higher the valence, the more obvious the effect on SB retardation performance; and the sooner the ion breaks through the barrier wall completely, that is, the wall＇s retardation performance for higher valent ions may decline.

关键词： Metal ions Soil-bentonite Barrier materials Retardation Mechanism

Analysis and Optimization of a Spatial Parallel Mechanism for a New 5-DOF Hybrid Serial-Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 60-68页

作者： Dong-sheng Zhang Yun-Dou Xu Jian-Tao Yao yong-sheng zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University

Hybrid manipulators have potentially application in machining industries and attract extensive attention from many researchers on the basis of high sti ness and high dexterity. Therefore,in order to expand the application prospects of hybrid manipulator,a novel 5?degree?of?freedom(DOF) hybrid serial?parallel manipulator(HSPM) is proposed. Firstly,the design plan of this manipulator is introduced. Secondly,the analysis of this manipulator is carried out in detail,including kinematics analysis,statics analysis,and workspace analysis. Especially,an amplitude equivalent method of disposing the over?constrained force/couple to the non?overconstrained force/couple is used in the statics analysis. Then,three performance indices are used to optimize the PM. Two of them have been widely used,and the third one is a new index which considers the characteristics of the actuated force. Based on the performance indices,the performance atlas is drawn and the optimal design of the PM is investigated. In order to satisfy the anticipant kinetic characteristics of the PM,the verification of the optimized physical dimension is done and the workspace based on the optimized physical dimension is carried out. This paper will lay good theoretical foundations for application of this novel HSPM and also can be applied to other hybrid manipulators.

关键词： Parallel mechanism Performance indices Optimal design Performance atlas

Smart responsive organic microlasers with multiple emission states for high-security optical encryption

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National Science Review 2021年第2期8卷 95-101页

作者： Zhenhua Gao Kang Wang yongli Yan Jiannian Yao yong sheng zhao Key Laboratory of photochemistry Institute of ChemistryChinese Academy of Sciences School of Materials Science & Engineering Qilu University of Technology(Shandong Academy of Sciences) University of Chinese Academy of Sciences

Modern high-security cryptography and optical communication call for covert bit sequences with high coding capacity and efficient authentication. Stimuli-responsive lasing emissions with easily distinguishable readout are promising in the coding field as a novel cryptographic primitive, while the application is frequently restricted by the limited number of emission states. Here, we report a strategy of achieving multiple competitive lasing signals in responsive organic microspheres where a donor–acceptor pair was introduced. The competitive lasing from the donor and acceptor was reversibly switched by modulating the competition between the radiative rate of the donor and the rate of energy transfer, and the generated multiple lasing signals enabled a quaternary coding for recognizable cryptographic implementation. Data encryption and extraction were demonstrated using a 4 × 4 microlaser array, showing vast prospects in avoiding the disclosure of security information. The results offer a comprehensive understanding of excited-state dynamics in organic composite materials, which may play a major role in high-security optical recording and information encryption.

关键词： organic laser nanophotonics excited-state process responsiveness optical encryption

Design and motion analysis of reconfigurable wheel-legged mobile robot

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Defence Technology（防务技术） 2022年第6期18卷 1023-1040页

作者： Shuo Zhang Jian-tao Yao Ying-bin Wang Zi-sheng Liu Yun-dou Xu yong-sheng zhao School of Mechanical Engineering Yanshan UniversityHebeiChina

An adaptive wheel-legged shape reconfigurable mobile robot,based on a scissor-like mechanism,is proposed for an obstacle detecting and surmounting robot,moving on complex *** robot can dynamically adjust its own shape,according to the environment,realizing a transformation of wheel shape into leg shape and vice *** wheel-legged mechanism has one degree of freedom,which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a ***,the force analysis of the conversion process of the wheel-legged mechanism is carried out,while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is *** results showed that the shape conversion can be better realized by increasing the friction factor of the trigger ***,the kinematics analysis of the robot,including climbing the obstacles,stairs and gully,is carried *** motion of the spokes tip is obtained,in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged *** parameters of the wheel-legged structure are optimized,to obtain better stability and obstacle climbing ***,a dynamic simulation model is established by ADAMS,to verify the obstacle climbing performance and gait rationality of the robot,in addition to a prototype *** results showed that the surmountable obstacle height of the robot is about3.05 times the spoke *** robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism,making it more suitable for field reconnaissance and exploration missions.

关键词： Mobile robots Scissor mechanism Kinematics ADAMS simulation Obstacle surmounting

Metal-organic framework microlasers

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Science Bulletin 2017年第1期62卷 3-4页

作者： Yuan Liu Haiyun Dong Fengqin Hu yong sheng zhao College of Chemistry Beijing Normal University Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences

The discovery and continued development of the lasers have led to a revolution in both fundamental researches and optoelectronic ***,micro/nanolasers that can generate intense coherent light signals at(sub)wavelength scale have become a research focus due to their potential applications in a variety of fields ranging from chemical and biological sensing to integrated optoelectronic circuitry[1,2].Organic materials are a kind of excel-

关键词：纳米激光器金属有机骨架光电集成电路有机材料微型激光器 Excel 基础研究持续发展

Methods for Force Analysis of Overconstrained Parallel Mechanisms： A Review

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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1460-1472页

作者： Wen-Lan Liu Yun-Dou Xu Jian-Tao Yao yong-sheng zhao Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao 066004 China Key Laboratory of Advanced Forging and StampingTechnology and Science of Ministry of National Education Yanshan University Qinhuangdao 066004 China

The force analysis of overconstrained PMs is relatively complex and difficult, for which the methods have always been a research hotspot. However, few liter- atures analyze the characteristics and application scopes of the various methods, which is not convenient for researchers and engineers to master and adopt them prop- erly. A review of the methods for force analysis of both passive and active overconstrained PMs is presented. The existing force analysis methods for these two kinds of overconstrained PMs are classified according to their main ideas. Each category is briefly demonstrated and evaluated from such aspects as the calculation amount, the compre- hensiveness of considering limbs＇ deformation, and the existence of explicit expressions of the solutions, which provides an important reference for researchers and engi- neers to quickly find a suitable method. The similarities and differences between the statically indeterminate prob- lem of passive overconstrained PMs and that of active overconstrained PMs are discussed, and a universal method for these two kinds of overconstrained PMs is pointed out. The existing deficiencies and development directions of the force analysis methods for overconstrained systems are indicated based on the overview.

关键词： Redundantly actuated PM ~ Passiveoverconstrained PM ~ Statically indeterminate problemForce analysis ~ Weighted generalized inverse

Organic composite materials:Understanding and manipulating excited states toward higher light-emitting performance

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Aggregate 2021年第4期2卷 31-42页

作者： Haiyun Dong Chunhuan Zhang Jiannian Yao yong sheng zhao Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijingChina School of Chemical Sciences University of Chinese Academy of SciencesBeijingChina

Organic composite materials have been attracting extensive research interest for light-emitting applications.A wide variety of luminescent organic composite materials have been synthesized,which are of great significance for both the investigation of basic photophysics and the realization of high-performance photonic ***-oriented syntheses of luminescent organic composite materials rely on the understanding and manipulating of molecular excited *** this review,we focus on the discussion about the structure design and dynamics modulation of the electronic excited states in the organic composite *** excited-state structures and dynamics involve singlet/triplet levels,vibronic transition,charge transfer,and energy transfer,and so on,while the light-emitting behaviors include fluorescence,phosphorescence,persistent luminescence,electroluminescence,and *** aim to give insight into the relationship between light-emitting properties and excited states of organic composite materials,which is beneficial for reaching higher tiers of design and applications of luminescent organic composite materials.

关键词： excited states molecular optoelectronics organic composite materials organic lasers organic lightemitting materials

3D-printed optical-electronic integrated devices

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Science China Chemistry 2019年第10期62卷 1398-1404页

作者： Yingying Liu Xianqing Lin Cong Wei Chuang Zhang Jiannian Yao yong sheng zhao Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The monolithic incorporation of electrical and optical components is critically important for achieving high-speed on-chip signal processing, but yet hard to satisfy the explosive growth in the demands on bandwidth and information density. Three-dimensional(3D) circuits, which are desirable for their improved performance in data handling, are ideal candidates to simultaneously promise high-capacity computing with improved speed and energy efficiency. In such highly integrated circuits, however, the selective electrical modulation of light signals is still difficult to achieve owing to the lack of controllable integration of microscale optical functional devices and modulation units. In this work, we demonstrate an electrically modulated microlaser module on a 3D-integrated microsystem composed of a dye-doped polymeric microcavity and an underneath microscale electrical heating circuit. The lasing mode was modulated based on electrical heating-assisted thermo-optic response of the polymeric matrices, which were further fabricated into coupled microdisks, yielding wavelength-tunable single-mode microlasers with selective electrical modulation. On this basis, a prototype of electrically controlled microlaser module with reduced signal crosstalk was achieved. The results will provide a useful enlightenment for the rational design of novel tunable optical devices with more complicated functionalities under far-field regulation, paving the way for the on-chip optoelectronic integration.

关键词： optical-electronic integration 3D printing photoelectric modulation organic laser