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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

Effect of Nb^(5+)and Cu^(2+)codoping on thermal properties of Gd_(2)Zr_(2)O_(7)ceramic

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Journal of Rare Earths 2021年第2期39卷 180-185页

作者： Tao Jiang min xie Lili Guan Xuanli Wang Xiwen Song School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China

In this work,Nb^(5+)and Cu^(2+)were selected to partially substitute Zr4+in Gd_(2)Zr_(2)O_(7)for studying the phase structure,microscopic morphology and thermal ***_(2)(Zr_(1-3 x/2)Nb_(x)CU_(x/2))_(2)O_(7)(x=0,0.05,0.1,0.15,0.2,0.25)ceramic materials were synthesized by high-temperature solid-state reaction *** results show that the Gd_(2)(Zr_(1-3 x/2)Nb_(x)Cu_(x)/2)_(2)O_(7)ceramics present cubic pyrochlore structure with clear grain boundaries and dense cell *** the thermal expansion coefficient of Gd_(2)(Zr_(1-3 x/2)Nb_(x)Cu_(x/2))_(2)O_(7)ceramics gradually decreases because of the incorporation of Nb^(5+)and Cu^(2+)into Zr-site in Gd_(2)Zr_(2)O_(7).Meanwhile,its thermal conductivity decreases firstly and then increases with the doping of Nb^(5+)and Cu^(2+),which reaches the lowest value for the composition of Gd_(2)(Zr_(0.85)Nb_(0.1)Cu_(0.05))_(2)O_(7).

关键词： Gd_(2)Zr_(2)O_(7) Co-doping Pyrochlore structure Thermal properties Rare earths

Research of cycloaliphatic epoxy resin and silicone rubber composite insulator interface based on four-electrode system and temperature rise model

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High Voltage 2023年第3期8卷 560-569页

作者： Yunsong Wang Yuhao Liu Hongwei Mei min xie Liming Wang Shenzhen International Graduate School(SIGS) Tsinghua UniversityShenzhenChina Research Institute of Tsinghua Pearl River DeltaGuangzhouChina

Interface degradation between mandrel and sheath can cause a decrease in insulation performance and mechanical strength of composite *** this study,the interface ageing properties of cycloaliphatic epoxy resin and silicone rubber composite insulator were compared.A water diffusion test was adopted to simulate the composite insulator ageing in a hot and humid environment.A four-electrode system was built to detect leakage current at different locations(mandrel,sheath and interface),which is an important basis for evaluating insulator *** ageing degree of insulator could be quantitatively characterised by leakage current *** was found that the infiltrated moisture had a great effect on insulation *** on the water absorption test result,the interface performance of two insulators was mainly influenced by their sheath sealing *** an auxiliary evaluation method,temperature rise during the test was recorded using an infrared *** experiment results showed that interface degradation was the main factor for the insulation performance decrease of silicone rubber composite ***,insulation level reduction of the cycloaliphatic epoxy resin was caused by the wet *** addition,a model for temperature rise of cycloaliphatic epoxy resin insulators was proposed based on good correspondence between sheath material and *** model incorporated multiple processes such as ageing and heating of insulators,and it can predict the early temperature rise well.

关键词： insulator composite interface

Hierarchical CoNi-LDH nanosheet array with hydrogen vacancy for high-performance aqueous battery cathode

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Journal of Energy Chemistry 2022年第6期31卷 9-15,I0001页

作者： Wang Qiao Bowen Jin Wenfu xie mingfei Shao min Wei State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Aqueous rechargeable multiple metal-ion storage battery (ARSB) has a large potential in energy storage devices due to their safe usage, low cost and high rate capability. Nevertheless, the performance of practical ARSB is largely restricted by low capacity and limited cathode materials. Herein, we demonstrate an efficient cathode material based on Co Ni-layered double hydroxide (LDH) nanosheets arrays with abundant hydrogen vacancy induced by electrochemical activation process for high performance of cations storage. Consequently, the electrochemical activated Co Ni-LDH (ECA-Co Ni-LDH) nanosheets arrays exhibit high metal ion (Li^(+), Na^(+), Zn^(2+), Mg^(2+) and Ca^(2+)) storage capacities, which is 9 times and 3 times higher that of unactivated Co Ni-LDH arrays and ECA-Co Ni-LDH without hierarchical structure, ***, the ECA-Co Fe-LDH also shows the possibility for practical applications in actual *** coupling with a Fe_(2)O_(3)/C anode, the assembled aqueous battery delivered a large energy density of 184.4 Wh kg^(-1)at power density of 4 Wh kg^(-1) in high voltage range of 0–2 V. To our best knowledge, such high energy density and large working window of our assembled aqueous battery is exceeded other LDH-based aqueous battery or supercapacitor, and the energy density almost comparable than that of commercial Li-ion batteries. Moreover, almost no measurable capacitance losses can be detected even after 10000 cycles. In addition, this work also provides a strategy to develop a high energy density cathode for multiple metal-ion storage batteries.

关键词： Layered double hydroxides Multiple ions intercalation Hierarchical structure Hydrogen vacancy Aqueous battery

Enhancement in optical absorption of CsI(Na)

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Nuclear Science and Techniques 2022年第3期33卷 53-61页

作者： Wei Cheng Pei-Sheng Liu min-ju Ying Feng-Shou Zhang Key Laboratory of Beam Technology of ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China National Laboratory of Heavy Ion Accelerator of Lanzhou Center of Theoretical Nuclear PhysicsLanzhou 730000China

Discussions pertaining to enhancement in the luminous efficiency of cesium iodide(CsI)detectors doped with sodium(Na)*** this study,the defect structure of one Cs atom replaced by one Na atom is calculated using the ab initio ***,the electronic band structures,densities of states,optical absorption spectra,phonons,and transport properties of CsI in perfect and defective structures are *** absorption spectra of CsI with and without Na impurities are *** is discovered that the impurity levels in the forbidden band are generated from the shell electron distributions of the impurity atoms,not from lattice ***,it is discovered that the optical absorption can be enhanced by doping CsI with Na.

关键词： CsI Na impurity Band structure Phonon Absorption spectrum

The Synthesis and Characterization of High Molecular Weight Poly(phenylene sulfide/ether)

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Chinese Chemical Letters 2006年第10期17卷 1373-1376页

作者： Ai Qun GU Mei ju xie Zi Li YU Institute of Materials Science ＆ Technology Analytical ＆ Testing Center Sichuan University Chengdu 610064

Poly（phenylene sulfide/ether）（PPSE） was synthesized from 4,4＇-dihydroxydiphenyl sulfide and 4,4＇-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR, ^1H NMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed. PPSE had the same reflex indices as poly（p-phenylene sulfide）, an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively. The product was soluble in common organic solvents such as NMP, N, N＇-dimethylformamide, N, N＇-dimethylacetamide and 1,2-dichloroethane.

关键词： Poly(phenylene sulfide/ether) (PPSE) synthesis characterization.

Numerical Simulation of Combustion Characteristics in High Temperature Air Combustion Furnace

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Journal of Iron and Steel Research International 2009年第2期16卷 6-10页

作者： WANG Ai-hua CAI Jiu-ju xie Guo-wei SEPA Key Laboratory on Eco-Industry Northeastern University Shenyang 110004 Liaoning China

The influences of air preheating temperature, oxygen concentration, and fuel inlet temperature on flame properties, and NOx formation and emission in the furnace were studied with numerical simulation. The turbulence behavior was modeled using the standard k-ε model with wall function, and radiation was handled using discrete ordinate radiation model. The PDF （probability density function） /mixture fraction combustion model was used to simulate the propane combustion. Additionally, computations of NOx formation rates and NOx concentration were carried out using a post-processor on the basis of previously calculated velocities, turbulence, temperature, and chemical composition fields. The results showed that high temperature air combustion （HiTAC） is spread over a much larger volume than traditional combustion, flame volume increases with a reduction of oxygen concentration, and this trend is clearer if oxygen concentration in the preheated air is below 10%. The temperature profile becomes more uniform when oxygen concentration in preheated air decreases, especially at low oxygen levels. Increase in fuel inlet tempera- ture lessens the mixing of the fuel and air in primary combustion zone, creates more uniform distribution of reactants inside the flame, decreases the maximum temperature in furnace, and reduces NOx emission greatly.

关键词： high temperature air combustion flame property temperature distribution NOx formation NOx emission

Lattice-Boltzmann simulation of microscale CH_4 flow in porous rock subject to force-induced deformation

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Chinese Science Bulletin 2014年第26期59卷 3292-3303页

作者： Yang ju Jinbo Wang Feng Gao Heping xie State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology State Key Laboratory of Coal Resources and Safe mining China University of Mining and Technology at Beijing School of Mechanics and Civil Engineering China University of Mining and Technology at Beijing College of Hydraulic and Hydroelectric Engineering Sichuan University

Accurate knowledge of the influence of rock deformation on the permeability of fluid flow is of great significance to a variety of engineering applications, such as simultaneous extraction of coal and gas, oil/gas exploitation, CO2 geological sequestration, and underground water conservation. Based on the CT representation of pore structures of sandstones, a LBM(Lattice Boltzmann Method) for simulating CH4 flow in pore spaces at microscale levels and a parallel LBM algorithm for largesize porous models are developed in this paper. The properties of CH4 flow in porous sandstones and the effects of pore structure are investigated using LBM. The simulation is validated by comparing the results with the measured data. In addition, we incorporate LBM and FEM to probe the deformation of microstructures due to applied triaxial forces and its influence on the properties of CH4 flow. It is shown that the proposed method is capable of visually and quantitatively describing the characteristics of microstructure, spatial distribution of flow velocity of CH4,permeability, and the influences of deformation of pore spaces on these quantities as well. It is shown that there is a good consistency between LBM simulation and experimental measurement in terms of the permeability of sandstone with various porosities.

关键词：格子玻尔兹曼方法岩石变形多孔模型微尺度流动甲烷 LBM模拟天然气开采受力

Red-blood-cell-shaped chitosan microparticles prepared by electrospraying

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Particuology 2017年第1期15卷 151-157页

作者： Xiaojie ju Xiaoxue Wang Zhuang Liu Rui xie Wei Wang Liangyin Chu School of Chemical Engineering Sichuan University Chengdu 610065 China State Key Laboratory of Polymer Materials Engineering and Collaborative Innovation Center for Biomaterials Science and Technology Sichuan UniversityChengdu 610065 China

Red-blood-cell-shaped chitosan microparticles with acid-triggered dissolution and auto-fluorescence were successfully fabricated by a simple strategy combining electrospraying with a solvent diffusion process controlled by solvent evaporation. The sizes of the prepared chitosan microparticles were rela- tively uniform. Control of the solvent diffusion process was crucial for the formation of microparticles with concave morphology. A chitosan aqueous solution containing 20vo1% ethanol as the evaporable solvent and 30 vol% dimethyl sulfoxide as the diffusible solvent was optimal for preparation of chitosan microparticles with the desired red-blood-cell-like size and shape. These chitosan microparticles will be highly attractive for many biological and biomedical aoolications.

关键词： Chitosan microparticle Red blood cell Electrospraying Solvent evaporation Solvent diffusion