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Enhancement in Magnetorheological Effect of Magnetorheological Elastomers by Surface Modification of Iron Particles

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Chinese Journal of Chemical Physics 2008年第1期21卷 87-92页

作者： Wan-quan Jiang Jing-jing Yao Xing-long Gong lin Chen Department of Chemistry University of Science and Technology of China Hefei 230026 China CA5 Key Laboratory of Mechanical Behavior and Design of Materials Department of Mechanics andMechanical Engineering University of Science and Technology of China Hefei 230027 China

In order to obtain magnetorheological （MR） elastomers with high magnetorheological effect, a family of anisotropic rubber-based MR elastomers was developed using a new form of chemical modification. Three different kinds of surfactants, i.e. anionic, nonionic and compound surfactants, were employed separately to modify iron particles. The MR effect was evaluated by measuring the dynamic shear modulus of MR elastomer with a magneto-combined dynamic mechanical analyzer. Results show that the relative MR effect can be up to 188% when the iron particles are modified with 15% Span 80. Besides the surface activity of Span 80, however, such high modifying effect is partly due to the plasticizing effect of Span 80. Compared with the single surfactant, the superior surface activity of compound surfactant makes the relative MR effect reach 77% at a low content of 0.4%. Scanning electron microscope observation shows that the modification of compound surfactant results in perfect compatibility between particles and rubber matrix and special self-assembled structure of particles. Such special structure has been proved beneficial to the improvement of the relative MR effect.

关键词： Magnetorheological elastomers Shear modulus Surfactant Microstructure

Layout optimization of steel reinforcement in concrete structure using a truss-continuum model

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Frontiers of Structural and Civil Engineering 2023年第5期17卷 669-685页

作者： Anbang CHEN Xiaoshan lin Zi-long ZHAO Yi Min XIE Centre for Innovative Structures and Materials School of EngineeringRMIT UniversityMelbourne 3001Australia Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100191China

Owing to advancement in advanced manufacturing technology,the reinforcement design of concrete structures has become an important topic in structural *** on bi-directional evolutionary structural optimization(BESO),a new approach is developed in this study to optimize the reinforcement layout in steel-reinforced concrete(SRC)*** approach combines a minimum compliance objective function with a hybrid trusscontinuum ***,a modified bi-directional evolutionary structural optimization(M-BESO)method is proposed to control the level of tensile stress in *** fully utilize the tensile strength of steel and the compressive strength of concrete,the optimization sensitivity of steel in a concrete–steel composite is integrated with the average normal stress of a neighboring *** demonstrate the effectiveness of the proposed procedures,reinforcement layout optimizations of a simply supported beam,a corbel,and a wall with a window are *** steel trajectories of SRC structures can be obtained using both *** area of critical tensile stress in concrete yielded by the M-BESO is more than 40%lower than that yielded by the uniform design and ***,the M-BESO facilitates a fully digital workflow that can be extremely effective for improving the design of steel reinforcements in concrete structures.

关键词： bi-directional evolutionary structural optimization steel-reinforced concrete concrete stress reinforcement method hybrid model

Quantum secure direct communication with entanglement source and single-photon measurement

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Science China(Physics,Mechanics & Astronomy) 2020年第11期63卷 12-19页

作者： Lu Yang JiaWei Wu ZaiSheng lin LiuGuo Yin GuiLu long State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Frontier Science Center for Quantum Information Beijing 100084China School of Information and Technology Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China Beijing Academy of Quantum Information Sciences Beijing 100093China

Quantum secure direct communication(QSDC)transmits information directly over a quantum *** addition to security in transmission,it avoids loopholes of key loss and prevents the eavesdropper from getting *** this article,we propose a QSDC protocol using entangled photon *** protocol differs from existing entanglement-based QSDC protocols because it does not perform Bell-state measurement,and one photon of the entangled pair is measured after the entanglement *** has the advantage of high signal-to-noise ratio due to the heralding function of entanglement pairs,and it also has the relative ease in performing single-photon *** protocol can use a practical entanglement source from spontaneous parametric down-conversion(SPDC);Gottesman-Lo-Lu¨tkenhaus-Preskill theory and the decoy state method give a better estimate of the error *** analysis is completed with Wyner’s wiretap channel theory,and the lower bound of the secrecy capacity is *** simulations were carried out to study the performance of the *** simulations demonstrated that the protocol with a practical SPDC entanglement source performed well and was close to the case with an ideal entanglement source.

关键词： quantum secure direct communication quantum secure communication quantum communication quantum information

Some notes on numerical investigation of three cavitation models through a verification and validation procedure

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Journal of Hydrodynamics 2023年第1期35卷 185-190页

作者： lin-feng Deng Yun long Huai-yu Cheng Bin Ji State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China Wuhan Second Ship Design and Research Institute Wuhan430064China

The present paper investigates the turbulent cavitating flow around the Clark-Y hydrofoil with special emphasis on the influence of cavitation models by verification and validation(V&V)*** solver coupled with the three major cavitation models(i.e.,Zwart-Gerber-Belamri,Schnerr and Sauer and full cavitation model,which are abbreviated to ZGB model,SS model and FC model respectively)is employed in this *** results indicate that the three cavitation models can properly reproduce the cavitation *** model and SS model give better prediction in the overall cavitation *** model exhibits an obvious under-estimation for the sheet cavity,and the predicted volume fraction is closely related to the turbulent *** verification and validation procedure is involved to quantitatively assess the accuracy of these three cavitation *** is indicated that the V&V procedure is suitable for the unsteady cavitating *** errors estimate is robust and conservative within the cavitation region,while gets closer to zero in the no-cavitation *** addition,ZGB model exhibits the highest overall accuracy among the three models,which further verifies its wide applicability.

关键词： Cavitating flow cavitation model verification and validation(V&V) error estimate

Physical Background of the Unified Scaling Law in Spiral Galaxies

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Chinese Physics Letters 2000年第12期17卷 935-936页

作者： ZOU Zhen-long HAN Jin-lin Beijing Astronomical Observatory and Beijing Astrophysical Center National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012

We discussed the physical background of the unified scaling law in spiral galaxies,and qualitatively obtained the power index of the empirical relation among the luminosity L,radius R and the rotation velocity *** also discussed the possible causes for the data dispersion on the plane in three-dimensional space of these parameters.

关键词： parameters galaxies rotation

The HD-Zip transcription factor GhHB12 represses plant height by regulating the auxin signaling in cotton

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Journal of Integrative Agriculture 2023年第7期22卷 2015-2024页

作者： LIU Yan WANG Wei-ping ZHANG lin ZHU long-fu ZHANG Xian-long HE Xin College of Agronomy Hunan Agricultural UniversityChangsha 410128P.R.China National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China

Upland cotton(Gossypium hirsutum L.)is the most important natural textile fiber crop *** height(PH)is a significant component of plant architecture,strongly influencing crop cultivation patterns,overall yield,and economic ***,cotton genes regulating plant height have not been fully ***,an HD-Zip gene(GhHB12)was isolated and characterized in cotton,which regulates the abiotic and biotic stress responses and the growth and development *** this study,we showed that GhHB12 was induced by ***,overexpression of GhHB12 induces the expression of HY5,ATH1,and HAT4,represses the spatial-temporal distribution,polar transport,and signaling of auxin,alters the expression of genes involved in cell wall expansion,and restrains the plant height in *** results suggest a role of GhHB12 in regulating cotton plant height,which could be achieved by affecting the auxin signaling and cell wall expansion.

关键词： cotton GhHB12 plant height auxin cell wall HD-Zip

Variation of hydro-environment during past four decades with underground sponge city planning to control flash floods in Wuhan,China:An overview

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Underground Space 2020年第2期5卷 184-198页

作者： Hui-long Wu Wen-Chieh Cheng Shui-long Shen Meng-Ying lin Arul Arulrajah Department of Civil Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering School of Civil EngineeringXi’an University of Architecture and TechnologyXi’an 710055China Department of Civil and Environmental Engineering College of EngineeringShantou UniversityShantouGuangdong 515063China Department of Civil Engineering School of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Civil and Construction Engineering Swinburne University of TechnologyVictoria 3122Australia

This paper presents a review of the variation in the hydro-environment over the past four decades in Wuhan,China,and discusses its close relationship with flash flood *** flash flood events have inundated underground infrastructures and resulted in significant economic losses and casualties,which are also discussed in relation to various external and internal *** external factors are predominantly owing to heavy rainstorms resulting from extreme climate *** internal factors predominantly include a decrease in wetland areas,changes in topography,and disrepair of drainage systems in urban *** the 1970s,lakes in Wuhan have been significantly reduced in size(by approximately 40%).This reduction in wetland area decreases the water storage capacity in urban areas,and the frequency of large flooding events thus increased from 0.1 event/year to approximately 0.2 event/***,the disrepair of drainage systems in urban areas has reduced their ability to resist flood *** in topography have also intensified the flood volume per unit time,further burdening the drainage *** 2016,Wuhan suffered from several large flooding events that led to some of the most severe economic losses in recorded *** drainage system at the urban center of Wuhan and proposed flood prevention methods are discussed in detail in this *** sponge city(SPC)concept has been attempted in Qingshan District,Wuhan,and its success proved the reliability of the theory.A SPC is believed to reduce the impacts of future flash floods in China and other developed and developing countries.

关键词： Flash flooding Wetland area Drainage system Wuhan Sponge city

Influence of CeO2 loading on structure and catalytic activity for NH3-SCR over TiO2-supported CeO2

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Journal of Rare Earths 2020年第8期38卷 883-890,I0002页

作者： Hongliang Zhang long Ding Hongming long Jiaxin Li Wei Tan Jiawei Ji Jingfang Sun Changjin Tang lin Dong School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243032China Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology) Ministry of EducationMa'anshan 243002China Analysis and Testing Central Facility Anhui University of TechnologyMa'anshan 243002China Jiangsu Key Laboratory of Vehicle Emissions Control School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

A series of supported CeO2/TiO2 catalysts were prepared to explore the influence of CeO2 loading on these catalysts for the selective catalytic reduction of NO3 by NH3(NH3-SCR).The catalysts were investigated in detail by means of XRD,Raman,H2-TPR,NH3-TPD,XPS,in situ DRIFTS,and NH3-SCR *** activity of the catalyst is closely related to the content of *** the loading of CeO2 is near the dispersion capacity(1.16 mmol Ce4+/100 m^2 TiO2),the catalytic activity is *** may be because that the dispersed CeO2 is the active species and the catalyst has appropriate redox property,along with the larger amounts of surface Ce content and surface adsorbed oxygen ***,a possible reaction mechanism via the Langmuir-Hinshelwood(L-H)mechanism is tentatively proposed to further understand the NH3-SCR reaction.

关键词： CeO2 Selective catalytic reduction Redox property Dispersion capacity Structure-activity relationship Rare earths

An efficient and surface-benign purification scheme for colloidal nanocrystals based on quantitative assessment

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Nano Research 2015年第10期8卷 3353-3364页

作者： Yu Yang Jiongzhao Li long lin Xiaogang Peng CenterforChemistryofNovel&High-PerformanceMaterials DepartmentofChemistryZhejiangUniversityHangzhou310027China

General application of ＂greener methods＂ to the synthesis of monodisperse colloidal nanocrystals introduces impurities, including metal carboxylate precursors, non-volatile solvents, free ligands, and non-nanocrystalline side products. These impurities seriously diminish the solution processability and potential applications of colloidal nanocrystals. A protocol was established for evaluating purification schemes. The results revealed that commonly applied purification schemes and their variants do not exhibit a high level of performance and may degrade the ligand surface coverage. A new scheme involving chloroformacetonitrile precipitation quantitatively removed all impurities from colloidal solutions of CdSe and CdS nanocrystals coated with a variety of carboxylate ligands. The new scheme was benign to the surface structure of nanocrystaMigands complexes and resulted in each nanocrystal bearing a close-packed monolayer of carboxylate ligands.

关键词： colloidal nanocrystals purification metal carboxylates ligands chloroform-acetonitrile