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Silicone Elastomer with High Elongation at Break Used in Digital Light Processing 3D Printing

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Chinese Journal of Polymer Science 2023年第11期41卷 1786-1795,I0010页

作者： tian-Xin Yu Ya-Yuan Liu fu-Yue tian Nan-Ying Ning Bing Yu Ming tian State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Carbon Fiber and functional Polymers Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029China

3D printing silicone elastomer has demonstrated great potential in diverse areas such as medical devices,flexible electronics and soft *** is of great value to investigate how to improve the mechanical properties,including tensile strength and elongation at break of printed *** this work,a light curing system that can be applied in silicone elastomer 3D printing is explored,which is composed of vinyl terminated polysiloxane as the macromer and thiol containing polysiloxane as the crosslinking agent,and a chain extension reaction is also introduced into this light curing system via the addition of the chain extender dithiol molecules,and a light curing system accompanied with chain extension is designed and realized based on the thiol-ene click reaction *** reinforced with silica fillers,the obtained light curing system can endow the light curing silicone elastomer with better mechanical properties under the condition of a lower viscosity of the precursor,the tensile strength and elongation at break can reach 525.5 k Pa and 601%,*** light curing system provides a feasible method to solve the contradiction between the viscosity of the precursor and the mechanical properties of the light curing elastomer in the digital light processing(DLP)3D printing field.

关键词： Silicone elastomer Thiol-ene click chemistry Light curing 3D-printing Chain extender

Black Hole Entropy with Modified Dispersion Relations

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Communications in Theoretical Physics 2009年第8期52卷 261-263页

作者： WANG fu-Jun gui Yuan-Xing ZHANG Yu School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024 China

There is much interest in resolving the quantum corrections to Bekenstein-Hawking entropy with a large length scale limit. The leading correction term ＆ given by the logarithm of black hole area with a model-dependent coefficient. Recently the research for quantum gravity implies the emergence of a modification of the energy-momentum dispersion relation （MDR）, which plays an important role in the modified black hole thermodynamics. In this paper, we investigate the quantum corrections to Bekenstein-Hawking entropy in four-dimensional Sehwarzschild black hole and Reissner-Nordstrom black hole respectively based on MDR.

关键词： black hole entropy dispersion relation

BUCKLING AND POSTBUCKLING ANALYSIS OF ELASTO-PLASTIC FIBER METAL LAMINATES

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Acta Mechanica Solida Sinica 2014年第1期27卷 73-84页

作者： Rengui Bi Yiming fu Yanping tian Chao Jiang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University College of Mechanical and Vehicle Engineering Hunan University School of Mechanical Engineering Hangzhou Dianzi University

The elasto-plastic buckling and postbuckling of fiber metal laminates （FML） are studied in this research. Considering the geometric nonlinearity of the structure and the elasto- plastic deformation of the metal layers, the incremental Von Karman geometric relation of the FML with initial deflection is established. Moreover, an incremental elasto-plastic constitutive relation adopting the mixed hardening rule is introduced to depict the stress-strain relationship of the metal layers. Subsequently, the incremental nonlinear governing equations of the FML subjected to in-plane compressive loads are derived, and the whole problem is solved by the iterative method according to the finite difference method. In numerical examples, the effects of the initial deflection, the loading state, and the geometric parameters on the elasto-plastic buckling and postbuckling of FML are investigated, respectively.

关键词： fiber metal laminates elasto-plastic buckling postbuckling

Moving target defense:state of the art and characteristics

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1122-1153页

作者： gui-lin CAI Bao-sheng WANG Wei HU tian-zuo WANG College of Computer National University of Defense Technology

Moving target defense(MTD) has emerged as one of the game-changing themes to alter the asymmetric situation between attacks and defenses in cyber-security. Numerous related works involving several facets of MTD have been published. However, comprehensive analyses and research on MTD are still absent. In this paper, we present a survey on MTD technologies to scientifically and systematically introduce, categorize, and summarize the existing research works in this field. First, a new security model is introduced to describe the changes in the traditional defense paradigm and security model caused by the introduction of MTD. A function-and-movement model is provided to give a panoramic overview on different perspectives for understanding the existing MTD research works. Then a systematic interpretation of published literature is presented to describe the state of the art of the three main areas in the MTD field, namely, MTD theory, MTD strategy, and MTD evaluation. Specifically,in the area of MTD strategy, the common characteristics shared by the MTD strategies to improve system security and effectiveness are identified and extrapolated. Thereafter, the methods to implement these characteristics are concluded. Moreover, the MTD strategies are classified into three types according to their specific goals, and the necessary and sufficient conditions of each type to create effective MTD strategies are then summarized, which are typically one or more of the aforementioned characteristics. Finally, we provide a number of observations for the future direction in this field, which can be helpful for subsequent researchers.

关键词： Moving target defense Security model function-and-movement model Characteristics

CSI-based passive intrusion detection bound estimation in indoor NLoS scenario

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fundamental Research 2023年第6期3卷 988-996页

作者： Linqing gui Wenyang Yuan fu Xiao Nanjing University of Posts and Telecommunications College of ComputerJiangsu 210023China

Passive intrusion detection is important for many indoor safety *** utilizing widespread WiFi infrastructures,channel state information(CSI)based intrusion detection methods have attractive advantages such as low cost,non-line-of-sight(NLoS)support,and privacy ***,existing CSI-based methods lack in-depth and intensive analysis of intrusion detection *** the best of our knowledge,this is the first work that precisely characterizes and models CSI-based intrusion detection bound in typical indoor NLoS scenario.A bound is defined as an intruder’s farthest position from the transmitter during intrusion *** derive a model for the bound,we first derived an intrusion-disturbed NLoS channel model by analyzing the influence of human intrusion on the NLoS wireless ***,based on the channel model,we further derived an intrusion detection bound *** on the derived bound model,we proposed a practical system to estimate the real intrusion detection *** experiments were conducted based on practical *** experimental and simulation results verified and demonstrated the effectiveness of the derived bound *** work not only reveals the fundamental performance limit of the basic intrusion detection method in an indoor NLoS scenario,but also provides a valuable reference for bound estimation for other fine-grained wireless sensing applications.

关键词： Intrusion detection Wireless sensing Commodity WiFi Channel state information Non line-of-sight

Real-Time Position and Attitude Estimation for Homing and Docking of an Autonomous Underwater Vehicle Based on Bionic Polarized Optical guidance

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Journal of Ocean University of China 2020年第5期19卷 1042-1050页

作者： CHENG Haoyuan CHU Jinkui ZHANG Ran gui Xinyuan tian Lianbiao The Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116024China

As an important tool for marine exploration, the autonomous underwater vehicle(AUV) must home in and dock at a docking station(DS) to be recharged, repaired, or to exchange information at set intervals. However, the complex and hostile underwater environment makes this process challenging. This study proposes a real-time method based on polarized optical guidance for determining the position and attitude of the AUV relative to its DS. Four polarized artificial underwater landmarks are positioned at the DS, which are recognized by the AUV vision system. Compared with light intensity, the polarization of a light beam is known to be better maintained at greater propagation distances, especially in underwater environments. The proposed method, which is inspired by the ability of marine animals to communicate, calculates the pose parameters in less than 10 ms without any other navigational information. The simulation results reveal that the angle errors are small and the position errors are no more than 0.116 m within 100 m in the coastal ocean. The results of underwater experiments further demonstrate the feasibility of the proposed method, which extends the operating distance of the AUV beyond what is currently possible while maintaining the precision of traditional optical guidance.

关键词： polarization optical guidance AUV underwater docking position and attitude estimation

Data-driven rational design of single-atom materials for hydrogen evolution and sensing

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Nano Research 2024年第4期17卷 3352-3358页

作者： Lei Zhou Pengfei tian Bowei Zhang fu-Zhen Xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China

Herein we proposed a data-driven high-throughput principle to screen high-performance single-atom materials for hydrogen evolution reaction(HER)and hydrogen sensing by combing the theoretical computations and a topology-based multi-scale convolution kernel machine learning *** the rational training by 25 groups of data and prediction of all 168 groups of single-atom materials for HER and sensing,respectively,a high prediction accuracy(>0.931 R^(2) score)was achieved by our *** show that the promising HER catalysts include Pt atoms in C_(4) and Sc atoms in C_(1)N_(3) coordination ***,Y atoms in C_(4) coordination environment and Cd atoms in C_(2)N_(2)-ortho coordination environment were predicted with great potential as hydrogen sensing *** method provides a way to accelerate the discovery of innovative materials by avoiding the time-consuming empirical principles in experiments.

关键词： machine learning single-atom materials sensing hydrogen evolution

Nicotinic Acetylcholine Receptor Gene Family of the Pea Aphid,Acyrthosiphon pisum

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Journal of Integrative Agriculture 2013年第11期12卷 2083-2091页

作者： LIU Yi-peng LIN Ke-jian LIU Yang gui fu-rong WANG gui-rong State Key Laboratory for Biology of Plant Diseases and Insect Pests/Institute of Plant Protection Chinese Academy of Agricultural Sciences College of Plant Protection Yunnan Agricultural University

The nicotinic acetylcholine receptors （nAchRs） are cholinergic receptors that form ligand-gated ion channels by ifve subunits in insect and vertebrate nervous systems. The insect nAChR is the molecular target of a class of insecticides, neonicotinoids. Here, we identiifed and cloned 11 candidate nAChR subunit genes in Acyrthosiphon pisum using genome-based bioinformatics combined modern molecular techniques. Most A. pisum nAChRs including α1, α2, α3, α4, α6, α8, and β1 show highly sequence identities with the counterparts of other insects examined. Expression proifles analysis showed that all subunit genes were expressed in adult head. At least two subunits have alternative splicing that obviously increase A. pisum nicotinic receptor diversity. This study will be invaluable for exploring the molecular mechanisms of neonicotinoid-like insecticides in sucking pests, and for ultimately establishing the screening platform of novel insecticides.

关键词： Acyrthosiphon pisum nicotinic acetylcholine receptor alternative splicing expression profile

Search for gamma-ray line signals around the black hole at the galactic center with DAMPE observation

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Science China(Physics,Mechanics & Astronomy) 2022年第6期65卷 150-158页

作者： tian-Ci Liu Ji-gui Cheng Yun-Feng Liang En-Wei Liang Laboratory for Relativistic Astrophysics Department of PhysicsGuangxi UniversityNanning 530004China

The adiabatic growth of a black hole(BH)may enhance the dark matter(DM)density surrounding it,causing a spike in the DM density *** spike around the supermassive BH at the center of the Milky Way may lead to a dramatic enhancement of the gamma-ray flux of DM annihilation from the galactic center(GC).In this work,we analyze the gamma-ray data of the innermost region(i.e.,the inner 1°)of the GC to search for potential line-like signals from the BH *** line-like signals could be generated in the process of DM particles annihilating into double *** adopt the gamma-ray data from the Dark Matter Particle Explorer(DAMPE).Although the DAMPE has a much smaller effective area than the Fermi-LAT,the gamma-ray line search can benefit from its unprecedented high energy *** significant line-like signals are found in our *** derive upper limits on the cross section of the annihilation based on this *** find that despite the DAMPE’s small effective area for photon detection,we can still place strong constraints on the cross section(≥10^(-27)cm^(3)s^(-1))in the spike scenario due to the very bright model-expected flux from the *** results indicate that either DM does not annihilate primarily through theγγchannel in the mass range we considered or no sharp density spike is present at the GC.

关键词： dark matter γ-ray telescopes black holes galactic center

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