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Chinese Chemical Letters 2013年第2期24卷 149-152页

作者： Yu-Rong Gao ling-ling Chu wei Guo Ting-Li ma Dalian Research and Design Institute of Chemical Industry State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of Technology

Received 7 September 2012 Received in revised form 27 November 2012 Accepted 11 December 2012 Available online 4 February 2013

关键词： DyesSolar cellsBenzodithiophenePower conversion efficiency

magnetoresistive behavior and magnetization reversal of NiFe/Cu/CoFe/IrMn spin valve GMRs in nanoscale

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International Journal of Minerals,Metallurgy and materials 2013年第7期20卷 700-704页

作者： Cong Yin Ze Jia wei-chao ma Tian-ling Ren Institute of Microelectronics & Tsinghua National Laboratory for Information Science and Technology Tsinghua University

The magnetoresistance behavior and the magnetization reversal mode of NiFe/Cu/CoFe/IrMn spin valve giant magnetoresistance （SV-GMR） in nanoscale were investigated experimentally and theoretically by nanosized magnetic simulation methods. Based on the Landau-Lifshitz-Gilbert equation, a model with a special gridding was proposed to calculate the giant magnetoresistance ratio （MR） and investigate the magnetization reversal mode. The relationship between MR and the external magnetic field was obtained and analyzed. Studies into the variation of the magnetization distribution reveal that the magnetization reversal mode, that is, the jump variation mode for NiFe/Cu/CoFe/IrMn, depends greatly on the antiferromagnetic coupling behavior between the pinned layer and the antiferromagnetic layer. It is also found that the switching field is almost linear with the exchange coefficient.

关键词： giant magnetoresistance (GMR) spin valves nanoscale magnetization reversal

Effect of W addition on hot deformation and precipitation behaviors of 19Cr2Mo ferritic stainless steel

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Journal of Iron and Steel Research International 2019年第5期26卷 425-434页

作者： Hou-long Liu Ming-yu ma ling-ling Liu Liang-liang wei Li-qing Chen State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 Liaoning China

The hot deformation behavior of 19Cr2Mo and 19Cr2Mo1W ferritic stainless steels was studied by using uniaxial hot compression tests on a thermomechanical simulator. The hot deformation was carried out at temperature ranging from 800 to 1150℃ and strain rates from 0.01 to 10 s^-1. Microstructure change and precipitation behavior during hot deformation were investigated by optical microscopy, electron probe microanalysis and transmission electron microscopy. The effects of temperature and strain rate on deformation behavior were obtained by a classical equation in Zener-Hollomon parameter. Since W addition to 19Cr2Mo1W steel could refine the size of the precipitates to enhance the precipitation strengthening and also had the effect of solution strengthening, the dynamic recrystallization, dynamic recovery and grain growth of 19Cr2Mo1W ferritic stainless steel were inhibited to a certain extent. The precipitate size of 19Cr2Mo1W steel was finer than that of 19Cr2Mo steel under the same deformation condition, which is due to the fact that the atomic diffusion is suppressed by W addition. W addition increased the amount of Laves phase in 19Cr2Mo1W steel, and thus Laves phase in 19Cr2Mo1W steel could be formed at higher temperature than that in 19Cr2Mo steel.

关键词： Ferritic stainless steel Tungsten Hot deformation behavior Microstructure evolution Precipitation Laves phase

matrine inhibits mycelia growth of Botryosphaeria dothidea by affecting membrane permeability

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Journal of Forestry Research 2019年第3期30卷 1105-1113页

作者： Jialiang Pan Xin Hao Hanwen Yao Kangkang Ge ling ma wei ma College of Forestry Northeast Forestry University Harbin 150040People’s Republic of China General Station of Forest and Grassland Pest management National Forestry and Grassland Administration Shenyang 110034People’s Republic of China College of Pharmacy Heilongjiang University of Chinese MedicineHarbin 150040People’s Republic of China

matrine is a promising botanical antifungal;however, the mechanism underlying the antifungal activity is yet limited. We studied the antifungal activity of matrine and the underlying mechanism in Botryosphaeria dothidea as a model strain. matrine strongly inhibited mycelial growth of B. dothidea in a dose-dependent manner. matrine-treated B. dothidea showed morphological and ultrastructural alterations, including shriveled hyphae, plasmolysis, and leakage of cytoplasm related to cell membrane deterioration. In addition, matrine caused significantly high conductivity and absorbance (260 nm) in extracellular matrices and low lipid contents in B. dothidea, indicating increased membrane permeability. Lipid peroxidation showed that matrine resulted in increased malondialdehyde content while enhancing the generation of reactive oxygen species and the activities of superoxide dismutase, catalase, and peroxidase. These results showed that matrine inhibited the mycelial growth of B. dothidea by enhancing cell membrane permeability via membrane lipid peroxidation.

关键词： matrine Antifungal activity Botryosphaeria dothidea Membrane permeability Lipid peroxidation

Influence of grain refinement on the corrosion behavior of metallic materials:A review

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International Journal of Minerals,Metallurgy and materials 2021年第7期28卷 1112-1126页

作者： Pan-jun Wang ling-wei ma Xue-qun Cheng Xiao-gang Li Institute of Advanced materials and Technology University of Science and Technology BeijingBeijing 100083China National materials Corrosion and Protection Scientific Data Center University of Science and Technology BeijingBeijing 100083China

Grain refinement can strengthen the mechanical properties of materials according to the classical Hall-Petch relationship but does not always result in better corrosion *** the past few decades,various techniques have been dedicated to refining grain,along with relevant studies on corrosion behavior,including general corrosion,pitting corrosion,and stress corrosion ***,the funda-mental consensus on how grain size influences corrosion behavior has not been *** paper reviews existing literature on the beneficial and detrimental effects of grain refinement on corrosion ***,the effects of microstructural changes(i.e.,grain boundary,dislo-cation,texture,residual stress,impurities,and second phase)resulting from grain refinement on corrosion behavior are *** grain re-finement not only has an impact on the corrosion performance,but also results in microstructural changes that have a non-negligible effect on corrosion behavior or even outweigh that of grain *** size is not the only factor affecting the corrosion behavior of metallic ma-terials;thus,the overall influence of microstructures on corrosion behavior should be understood.

关键词： corrosion behavior grain refinement microstructure high-temperature oxidation

Simulative technology for auxiliary fuel tank separation in a wind tunnel

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Chinese Journal of Aeronautics 2016年第3期29卷 608-616页

作者： ma Xin Liu wei Chen ling Li Xiao Jia Zhenyuan Shang Zhiliang Key Laboratory for Precision and Non-traditional machining Technology of the Ministry of Education Dalian University of Technology

In this paper, we propose a simulative experimental system in wind tunnel conditions lbr the separation of auxiliary fuel tanks from an aircraft. The experimental system consists of a simulative release mechanism, a scaled model and a pose measuring system. A new release mechanism was designed to ensure stability of the separation. Scaled models of the auxiliary fuel tank were designed and their moment of inertia was adjusted by installing counterweights inside the model. Pose param- eters of the scaled model were measured and calculated by a binocular vision system. Additionally, in order to achieve high brightness and high signal-to-noise ratio of the images in the dark enclosed wind tunnel, a new high-speed image acquisition method based on miniature self-emitting units was pre- sented. Accuracy of the pose measurement system and repeatability of the separation mechanism were verified in the laboratory. Results show that the position precision of the pose measurement system can reach 0.1 mm, the precision of the pitch and yaw angles is less than 0.1° and that of the roll angle can be up to 0.3°. Besides, repeatability errors of models＂ velocity and angular velocity controlled by the release mechanism remain small, satisfying the measurement requirements. Finally, experiments for the separation of auxiliary fuel tanks were conducted in the laboratory.

关键词： Aircraft auxiliary equipmentBinocular vision Position and attitude mea-surement Release mechanism Simulation experiment

Preparation of TiO2 Nanocrystals/Graphene Composite and Its Photocatalytic Performance

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Chinese Journal of Chemical Physics 2014年第3期27卷 321-326页

作者： ling-juan Deng Yuan-zi Gu wei-xia Xu Zhan-ying ma School of Chemistry & Chemical Engineering Xianyang Normal University Xianyang 712000 China

TiO2 nanocrystals/graphene （TiO2/GR） composite are prepared by combining flocculation and hydrothermal reduction technology using graphite oxide and TiO2 colloid as precursors. The obtained materials are examined by scanning electron microscopy, transition electron microscopy, X-ray diffraction, N2 adsorption desorption, and ultraviolet-visible diffuse spectroscopy. The results suggest that the presence of TiO2 nanocrystals with diameter of about 15 nm prevents GR nanosheets from agglomeration. Owing to the uniform distribution of TiO2 nanocrystals on the GR nanosheets, TiO2/GR composite exhibits stronger light absorption in the visible region, higher adsorption capacity to methylene blue and higher efficiency of charge separation and transportation compared with pure TiO2. Moreover, the TiO2/GR composite with a GR content of 30% shows higher photocatalytic removal efficiency of MB from water than that of pure TiO2 and commercial P25 under both UV and sunlight irradiation.

关键词： TiO2 nanocrystals/graphene composite Photocatalyst Chemical adsorptivity Extended light absorption Efficient charge separation

Microcellular foamed polyamide 6/carbon nanotube composites withsuperior electromagnetic wave absorption

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Journal of materials Science & Technology 2022年第22期117卷 215-224页

作者： Menglong Xu Linfeng wei Li ma Jiawei Lu Tao Liu ling Zhang ling Zhao Chul B.Park State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Mechanical and Industrial Engineering University of Toronto5 King’s College RoadTorontoOntario M5S 3G8Canada Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Electromagnetic (EM) wave pollution causing damage to precision equipment and threatening thehealth of living organisms has attracted considerable attention. Herein, promising microcellular foamedpolyamide 6 (PA6)/carbon nanotube (CNT) composites for highly efficient EM wave absorption were successfully fabricated using supercritical CO_(2) foaming. Nanocomposites foams with a void fraction rangingfrom 38.7% to 85.1% were achieved, providing a platform to assess the correlation of the electrical conductivity, the dielectric permittivity and the EM wave absorption properties with porosity. Notably, theFoam-257.5C sample with a void fraction of 38.7% exhibited outstanding EM wave absorption characteristics at a thickness of only 1.59 mm and an ultra-low reflection loss value of -55.3 dB (99.9997% wave absorption). Most importantly, the effective absorption bandwidth (EAB) of the Foam-257.5C sample couldcover the entire Ku band (12.4–18 GHz) by slightly adjusting the thickness from 1.20 to 1.60 mm. Thesuperior EM wave absorption performance of the Foam-257.5C sample was attributed to multiple reflections and scattering at the solid-gas interfaces, favorable impedance matching due to the existence ofa large polymer-air interface area, conductive loss near the interfaces and interfacial polarization. Thus,this study offers an eco-friendly, simple and versatile methodology to develop high-efficiency, flexiblepolymer-based EM wave absorbents.

关键词： Polymer nanocomposites Supercritical CO_(2)foaming Void fraction Dielectric properties Electromagnetic wave absorption

Structural Design of a Tall Building with Underpinning Structure in Guangzhou

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 93-101页

作者： Yu-Hong ling Hong-wei ma Shao-Feng Li Architectural Design and Research Institute South China University of Technology School of Civil Engineering and Transportation South China University of Technology

This paper introduces the structural design optimization of a tall building with reinforced concrete frame-core shear walls in Guangzhou *** decrease the construction cost,wide flat beam with 400 mm ×650 mm rectangular cross-section are adopted for main *** measures are used to decrease noncoincident centers of mass and *** subway tunnels cross the building underground,inclined columns,the second and third floor underground together function as the underpinning *** from traditional transform beam,the proposed underpinning structures show good performance without using large dimensional bending *** attentions should be paid to the beams connecting with the inclined column in the underpinning structures,and these beams show large tensile or compressive *** observations after completion construction indicate that the building as well as the proposed design measures work well.

关键词： tall building subway tunnel structural design underpinning structure

Indirect somatic embryogenesis and regeneration of Fraxinus mandshurica plants via callus tissue

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Journal of Forestry Research 2021年第4期32卷 1613-1625页

作者： Yang Liu Cheng wei Hao Wang Xiao ma Hailong Shen ling Yang State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China State Forestry and Grassland Administration Engineering Technology Research Center of Native Tree Species Harbin 150040People’s Republic of China

Somatic embryogenesis of Fraxinus mandshurica has the problems of low somatic embryo(SE) yield,unsynchronized SE development,and a high percentage of deformed *** aimed to improve *** SE production by synchronizing SE development,improving SE quality,and inducing root formation to obtain complete regenerated *** of immature zygotic embryos of *** were induced to form callus and then *** SE induction percentage from explants differed among 32 mother trees,and the one with the highest SE induction percentage(29.8%) was used for further *** highest callus induction percentage was94.2% on 1/2-strength Murashige and Skoog medium(MS1/2)supplemented with 0.15 mg·L^(-1) naphthalene acetic *** highest callus proliferation coefficient(240.5) was obtained on McCown's Woody Plant Medium containing 0.1 mg·L^(-1)6-benzyl adenine and 0.15 mg·L^(-1) 2,4-dichlorophenoxyacetic *** highest number of SEs(1020.5 g~(-1) fresh weight) was obtained on MS1/2 medium supplemented with1 mg·L^(-1) *** highest number of cotyledon embryos(397/g fresh weight) was obtained by incubating materials on medium containing 1 mg·L^(-1) abscisic acid and then applying a drying *** cotyledon embryos were milky white,uniformly sized(average length 4.7 mm),and 80% of them were *** SE rooting percentage on 1/2 MS medium containing 0.01 mg·L^(-1) NAA was 37.5%.Overall,the germination percentage of SEs was 26.4%,and complete regenerated plants were obtained after transplanting and *** results provide more possibilities for the preservation and breeding of ***.

关键词： Fraxinus mandshurica Somatic embryogenesis Callus induction Cell differentiation Plant regeneration