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Amino-functionalized magnetic bacterial cellulose/activated carbon composite for Pb^2＋ and methyl orange sorption from aqueous solution

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Journal of Materials Science & Technology 2018年第5期34卷 855-863页

作者： Xiaogui Huang Xiaozhang zhan Cuilian Wen feng Xu Lijin Luo College of Materials Science and Engineering Fuzhou University Fuzhou 350116 China Key Laboratory of eco-Materials Advanced Technology (fuzhou University) Fujian Province University Fuzhou 350116 China fujian Provincial Key Laboratory of Screening for Novel Microbial Products Fujian Institute of Microbiology Fuzhou 350007 China

A new nanostructured amino-functionalized magnetic bacterial cellulose/activated carbon（BC/AC）composite bioadsorbent（AMBCAC）was prepared for removal of Pb^2＋ and methyl orange（MO）from aqueous *** results demonstrated that the equilibrium adsorption capacity（qe）for Pb^2＋ obviously increases by 2.14 times after introduction of amino groups,the optimum p H for Pb^2＋and MO adsorption was 5.0 and 3.0,respectively,and the qeof AMBCAC was 161.78 mg g^-1 for Pb^2＋ and 83.26 mg g^-1 for MO under the optimal conditions in this *** kinetics and adsorption isotherm data of the sorption process were well fitted by pseudo-second-order kinetic model and Langmuir isotherm *** thermodynamic results（the Gibbs free energy change G〈0,the enthalpy change H〉0,the entropy change S〉0）implied that the adsorption process of Pb^2＋ and MO was feasible,endothermic and spontaneous in *** results support that the AMBCAC composite developed in this work can provide a cheap and efficient way for easy removal of both Pb^2＋ and MO as a promising adsorbent candidate for wastewater treatment.

关键词： Bacterial cellulose Activated carbon Pb^2+ Methyl orange Adsorption

An Efficient CSI Feedback Scheme for Dual-Polarized MIMO Systems Using Layered Multi-Paths Information

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China Communications 2017年第5期14卷 91-104页

作者： feng Zheng Yijian Chen Qian zhan Jie zhang Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and TelecommunicationsBeijing 100876BeijingChina ZTE Corporation Shenzhen 518055China Beijing University of Posts and Telecommunications Beijing 100876China Department of Electronic and Electrical Engineering The University of SheffieldWestern BankShelffield S102TNUK

Massive MIMO is one of tile enabling technologies tbr beyond 4G and 5G systems due to its ability to provide beamforming gain and reduce interference Dual-polarized antenna is widely adopted to accommodate a large number of antenna elements in limited space. However, current CSI（channel state information） feedback schemes developed in LTE for conventional MIMO systems are not efficient enough for massive MIMO systems since the overhead increases almost linearly with the number of antenna. Moreover, the codebook for massive MIMO will be huge and difficult to design with the LTE methodology. This paper proposes a novel CSI feedback scheme named layered Multi-paths Information based CSI Feedback （LMPIF）, which can achieve higher spectrum efficiency for dual-polarized antenna system with low feedback overhead. The MIMO channel is decomposed into long term components （multipath directions and amplitudes） and short term components （multipath phases）. The relationship between the two components and the optimal precoder is derived in closed form. To reduce the overhead, different granularities in feedback time have been applied for the long term components and short term components Link and system level simulation results prove that LMPIF can improve performance considerably with low CSI feedback overhead.

关键词： communication and information system: efficient CSI feedback: channel characteristie analysis dual-polarized: massive MIMO: layered Multi-Paths information codeword model

Effect of Cr on Characteristic of Rust Layer Formed on Low Alloy Steel in Flow-accelerated Corrosion Environment

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Journal of Iron and Steel Research International 2016年第6期23卷 602-607页

作者： feng CHAI Shan JIANG Cai-fu YANG Department of Engineering Steels Central Iron and Steel Research Insititute

The flow-accelerated corrosion experiments were carried out to research the effect of Cr on the rust layers formed on the carbon steel and Cr-containing steel,as well as the structure of rust layer of the two experimental *** influence of Cr on the flow-accelerated corrosion resistance and the corrosion morphology of inner rust layer formed on the Cr-containing steel were studied by the methods of polarization curves,scanning electron microscope,transmission electron microscope,and X-ray photoelectron *** distribution of Cr and its form of existence in the inner rust layer were *** results show that corroded mass loss of Cr-containing steel is lower than that of carbon steel and its inner rust layer is *** exists in the form of Fe2CrO4 and is enriched in the inner rust *** concentration could make the inner rust layer exhibit the tendency of *** phenomenon is related to fine *** inner rust layer becomes more compact because of the formation of fine Fe2CrO4,and the protectiveness of inner rust layer could be improved remarkably.

关键词： accelerated photoelectron amorphous remarkably steels finer enriched cathodic hence attributed

Synthesis of ultrathin semicircle-shaped copper nanowires in ethanol solution for low haze flexible transparent conductors

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Nano Research 2018年第7期11卷 3899-3910页

作者： Ye zhan~ Jiangna Guo Dan Xu Yi Sun feng Yan Jiangsu Key Laboratory of Advanced functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 China

Copper nanowires （CuNWs） are becoming an indispensable item for next- generation transparent optical devices due to their excellent conductivity and transparency. In this work, ultrathin semicircle-shaped copper nanowires （SCuNWs） with a diameter of - 15 nm and a length of - 30 μm （aspect ratio of -2,000） were synthesized in ethanol solution. The mechanism and factors that affect the morphology and dispersity of the SCuNWs were investigated. The prepared SCuNWs were coated on polyethylene terephthalate （PET） or polyd- imethylsiloxane （PDMS） substrate to fabricate flexible transparent conductors （FTCs）. The fabricated FTCs exhibited excellent optoelectrical performance and low haze. In addition, the fabricated FTCs showed high mechanical stability during stretching and bending, indicating their great potential in flexible optical devices.

关键词： copper nanowires semicircle-shaped ultrathin low haze flexible transparent conductors

Formability enhancement in hot spinning of titanium alloy thin-walled tube via prediction and control of ductile fracture

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Chinese Journal of Aeronautics 2022年第2期35卷 320-331页

作者： Pengfei GAO Chao YU Mingwang fu Lu XING Mei zhan Jing GUO State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of High-Performance Precision Forming Technology and EquipmentSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HornKowloonHong Kong 999077China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

The damage and fracture in hot spinning of titanium alloy is a very complex process under the combined effects of microstructure evolution and stress *** this study,their dependences on processing parameters were investigated by an integrated FE model considering microstructure and damage evolution,and revealing the effects of microstructure and stress states on damage *** results show that the inner surface of workpiece with the largest voids volume fraction is the place with the greatest potential of *** is mainly attributed to the superposition effects of positive stress triaxiality and the smallest dynamic recrystallization(DRX)fraction andβphase fraction at the inner *** damage degree is decreased gradually with the increase of initial spinning temperature and roller fillet ***,it is first decreased and then increased with the increases of spinning pass and roller feed rate,which can be explained based on the variations ofβphase fraction,DRX fraction,stress state and tensile plastic strain with processing *** addition,the dominant influencing mechanisms were identified and ***,the thickness reduction without defect in the hot spinning of TA15 alloy tube is greatly increased by proposing an optimal processing scheme.

关键词： Control of ductile fracture Dynamic recrystallization Forming limit Hot spinning Titanium alloy tube

Oxidation Kinetics,Structural Changes and Element Migration during Oxidation Process of Vanadium-titanium Magnetite Ore

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Journal of Iron and Steel Research International 2016年第11期23卷 1160-1167页

作者： feng PAN Qing-shan ZHU zhan DU Hao-yan SUN State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences Beijing 100039China

The oxidation kinetics, structural changes, and elements migration during the oxidation process of the va- nadium-titanium magnetite （VTM） ore were analyzed. Kinetics analysis indicated that the oxidation process was con- trolled by diffusion control and could be divided into interface diffusion and lattice diffusion with apparent activation energy of 99.69 kJ/mol and 144.08 kJ/mol in the range of 800--1000℃, respectively. The surface structure changed with the oxidization temperature as follows： dense surface→nano sized sheets→submicron particles→molten particles. The compact structure changed into porous one because of the elements migration and enrichment. Both Fe and Ti elements migrated in the opposite direction during the oxidation process. The V etement in the raw ore stably existed in the form of V^5＋ state, some vanadium migrated and occupied the tetrahedral sites of the hematite during the oxidation process.

关键词： vanadium-titanium magnetite ore oxidation kinetics structural change element migration

Research on Catalytic Properties of Palladium Catalyst Prepared by Biological Reduction Method

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China Petroleum Processing & Petrochemical Technology 2013年第2期15卷 24-30页

作者： zhang feng fu Jiquan School of Materials Science and Engineering Beijing Institute of Fashion Technology

This paper relates to highly dispersed supported Pd/MWCNTs and Fd/a-Al2O3 catalysts prepared by biological reduction method. The physico-chemical properties and the difference in catalytic activity of Pd catalysts prepared by bio- logical reduction method and chemical method, respectively, were investigated using XRD, TEM and specific surface char- acterization methods. The catalytic properties of catalysts were studied through activity evaluation means. The test results showed that the catalysts prepared by biological method were characteristic of small Pd nanoparticle size, good dispersion and low agglomeration, while possessing a high activity and stability in styrene hydrogenation reaction in comparison with catalysts prelgared via the chemical method.

关键词： Pd/MWCNTs Pd/a- Al2O3 biological reduction ginkgo leaf Pd nanoparticles

Two Special Solutions of the Non-ideal Magnetohydrodynamics

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Chinese Physics Letters 2000年第5期17卷 382-384页

作者： feng Xue-Shang LIU Yong WEI feng-Si YE zhan-Yin Laboratory of Numerical Study for Heliospheric Physics Center for Space Sciences and Applied ResearchChinese Academy of SciencesBeijing 100080

A special transformation is found to solve the Magnetohydrodynamic equations,by which two classes of exactanalytic time-dependent solutions of magnetic annihilation for incompressible magnetic fluid have been *** solutions derived here possesses scaling property with time t as the scale *** find that the currentcan perform the soliton-like behaviour in the case of asymmetric *** relevant evolution characteristics inthe process of magnetic annihilation are also revealed.

关键词： annihilation soliton behaviour

A hybrid multidimensional Riemann solver to couple self-similar method with MULTV method for complex flows

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Chinese Journal of Aeronautics 2021年第7期34卷 29-38页

作者： feng QU Di SUN Junjie fu Junqiang BAI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

Since proposed,the self-similarity variables based genuinely multidimensional Riemann solver is attracting more attentions due to its high resolution in multidimensional complex ***,it needs numerous logical operations in supersonic cases,which limit the method’s applicability in engineering problems *** order to overcome this defect,a hybrid multidimensional Riemann solver,called HMTHS(Hybrid of MulTv and multidimensional HLL scheme based on Self-similar structures),is *** simulates the strongly interacting zone by adopting the MHLLES(Multidimensional Harten-Lax-van Leer-Eifeldt scheme based on Self-similar structures)scheme at subsonic speeds,which is with a high resolution by considering the second moment in the similarity ***,it adopts the MULTV(Multidimensional Toro and Vasquez)scheme,which is with a high resolution in capturing discontinuities,to simulate the flux at supersonic *** numerical experiments,including both one-dimensional cases and twodimensional cases,are ***-dimensional moving contact discontinuity case and sod shock tube case suggest that HMTHS can accurately capture one-dimensional expansion waves,shock waves,and linear contact ***-dimensional cases,such as the double Mach reflection case,the supersonic shock/boundary layer interaction case,the hypersonic flow over the cylinder case,and the hypersonic viscous flow over the double-ellipsoid case,indicate that the HMTHS scheme is with a high resolution in simulating multidimensional complex ***,it is promising to be widely applied in both scholar and engineering areas.

关键词： Complex flows Computational fluid dynamics Multidimensional Riemann solver Self-similar