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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 391-402页

作者： Wen-chao Dong Ming-Yue Wen Hui-Yong Pang shan-Ping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Wuyang Iron and Steel Co.Ltd. Pingdingshan 462500China

The effects of tempering temperatures on the microstructure and mechanical properties of the simulated coarse-grain heataffected zone(CGHAZ) and inter-critical heat-affected zone(ICHAZ) were investigated for a high-strength-high-toughness combination marine engineering *** results demonstrate that the microstructure of the simulated CGHAZ and ICHAZ after tempering is characterized by tempering sorbites and coarse grain in the simulated *** tempering temperature increases,the tensile strength of the simulated CGHAZ and ICHAZ decreases and the Charpy absorbed energy of the simulated ICHAZ at-50℃increases remarkably,but the impact toughness of the simulated CGHAZ is not *** tempering at 550℃,the coarse flake carbides,which distribute at the prior austenite grain and martensite lath boundaries,deteriorate the impact toughness of the simulated *** the increase in tempering temperature,the morphology and the size of the carbides gradually change from coarse flake to fine granular,which is beneficial to the improvement of impact ***,the coarse-grain size of the simulated CGHAZ and the M23 C6-type carbide precipitated along the grain boundaries weakens the enhancing effect of carbides on impact toughness.

关键词： High-strength-high-toughness combination steel Post-weld heat treatment Heat-affected zones(HAZs) Carbides Impact toughness

Remote,selective,and in situ manipulation of liquid droplets on a femtosecond laser-structured superhydrophobic shape-memory polymer by near-infrared light

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Science China Chemistry 2021年第5期64卷 861-872页

作者： Xue Bai Jiale Yong chao shan Yao Fang Xun Hou Feng Chen State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China

Droplet manipulation plays a significant role in the fields of biomedical detection,microfluidics,and chemical ***,it still remains a great challenge to simultaneously achieve remote,selective,and in situ droplet manipulation on the same ***,Fe_(3)O_(4)nanoparticles were doped in a shape-memory polymer(SMP)to prepare a photothermal-responsive Fe_(3)O_(4)-SMP composite which showed remarkable near-infrared(NIR)light-triggered shape-memory *** micropillar array was constructed on such Fe_(3)O_(4)-SMP composite through femtosecond laser microfabrication and fluoroalkylsilane *** surface wettability of the as-prepared surface can transform from a low-adhesive sliding state to a high-adhesive pinning state as the micropillars are deformed by ***,the deformed micropillars can stand up and restore to their original morphology under remote NIR light irradiation,resulting in the reversible and repeatable recovery of the ultralow-adhesive *** such light-triggered wettability switching,the droplets pinning on the sample surface can be remotely,selectively,and in situ ***,the superhydrophobic Fe_(3)O_(4)-SMP surface is successfully applied in lossless liquid transfer,selective droplet release,and droplet-based *** as-fabricated superhydrophobic surfaces with NIR light-controlled reversible wettability will hold great promise in the fields of liquid manipulation,lab-on-a-chip,and microfluidics.

关键词： droplet manipulation superhydrophobicity shape-memory polymer femtosecond laser light responsive

Visual inference of flow flux via free surface PDE model and image sequence assimilation

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IET Cyber-Systems and Robotics 2019年第1期1卷 20-27页

作者： shan Guo chao Xu Ka Fai Cedric Yiu School of Mathematical Sciences Zhejiang UniversityHangzhouPeople's Republic of China Department of Applied Mathematics Hong Kong Polytechnic UniversityHong KongPeople's Republic of China Institute of Cyber-Systems and Control Zhejiang UniversityHangzhouPeople's Republic of China

The free-surface flows,such as flows in rivers,lakes,and tides,play an important role in hydraulic engineering and environmental ***,due to their complex and changeable characters,the precise evolution procedure is quite difficult to *** this study,the authors propose a novel framework to reconstruct the free-surface flow modelled by the shallow water equations by assimilating the images *** particular,the ensemble Kalman filter framework is employed to implement the assimilation *** efficiency of the proposed strategy has been verified through numerical simulations in which the accurate flow field in different situations could be obtained within limited assimilation steps.

关键词： process. flow steps

Cathodic behavior of molten CaCl_2-CaO and CaCl_2-NaCl-CaO

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 791-794页

作者： Shu-lan Wang Wei Wang Shi-chao Li shan-hui Cao Department of Chemistry Northeastem University Shenyang 110004 China

The cathodic behavior of molten CaCl2, CaCl2-CaO and equimolar CaCl2-NaCl-CaO was studied by cyclic voltammograms and constant potential polarization at temperatures of 1123 to 1173 K on molybdenum and titanium electrodes. The diffusion coefficient of Ca2＋（CaO） in molten CaCl2-CaO was calculated from the linear relationship between the square root of scan rate and the peak current density. The deposition potentials and the potential temperature coefficient of CaO in molten CaCl2-0.5mol%CaO and CaCl2-NaCl-0.5mol%CaO were also obtained from their cyclic voltammograms. The result shows that CaO is more easily reduced than CaCl2. The addition of NaCl in molten CaCl2-CaO induces the underpotential electrodeposition of CaO.

关键词： molten salts calcium oxide cyclic voltammetry polarization

Fiber Bending Flexibility Evaluation by Worm-like Chain Model

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Chinese Journal of Polymer Science 2022年第5期40卷 526-531页

作者： chao Jin Hui Yu Chun-Fang Wu Hai-Bo Zhao shan-shan Jin Yu-Liang Yang Hong-Dong Zhang Institute for Preservation and Conservation of Chinese Ancient Books Fudan UniversityShanghai 200433China Statekey laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

A new method for characterizing fiber bending flexibility was developed by worm-like chain model proposed by Kratky-Porod,[1]which was first introduced to the pulp and paper field in this *** the three types of pulps,the experimental results were compared with the KP chain model,and the resulting determination coefficients were all above 0.95,which proved that the model was feasible to be applied to these three *** relation between fiber bending rigidity and that of cellulosic chains inside was discussed to deduce the fiber bending *** flexibility of an individual fiber can be approximated as the contribution of that of all the cellulose chains *** this method,the fiber flexibility values were determined to be in the range of 0.6×10^(11)-3.5×10^(11)N^(-1)·m^(-2),which was comparable to that of the conventional methods recorded in the literature.

关键词： Worm-like chain Fiber persistence length Fiber bending flexibility

A New Signature Scheme with Shared Verification

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The Journal of China Universities of Posts and Telecommunications 2006年第2期13卷 66-69页

作者： JIA Xiao-yun LUO Shou-shan YUAN chao-wei School of Continuing Education Beijing University of Posts and Telecommunications Beijing 100876 P.R. China School of Software Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China National Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 P.R. China

With expanding user demands, digital signature techniques are also being expanded greatly, from single signature and single verification techniques to techniques supporting multi-users. This paper presents a new digital signature scheme with shared verification based on the fiat-shamir signature scheme. This scheme is suitable not only for digital signatures of one public key, but also for situations where multiple public keys are required. In addition, the scheme can resist all kinds of collusion, making it more practicable and safer. Additionally it is more efficient than other schemes.

关键词： digital signature shared verification verifiable secret sharing

Eclogite-melt/peridotite reaction: Experimental constrains on the destruction mechanism of the North China Craton

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Science China Earth Sciences 2010年第6期53卷 797-809页

作者： WANG chao JIN ZhenMin GAO shan ZHANG JunFeng ZHENG Shu State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China

To study the mechanism of melt-peridotite reaction pertinent to the destruction of the North China Craton (NCC) lithosphere, a series of experiments were performed at a pressure of 2.0 GPa and temperatures from 1250 to 1400°C using Bixiling eclogite and Damaping peridotite as starting materials. The experimental results show that the reaction between eclogite melt and peridotite causes dissolution of olivine and orthopyroxene and precipitation of clinopyroxene in the melt. The experimental run products, characterized by a lherzolite/pyroxenite/garnet-pyroxenite sequence, are consistent with the mantle xenoliths in the Neogene Hannuoba basalt of the NCC found by Liu et al. (2005). It suggests that the mafic lower continental crust was probably recycled into the mantle during the Mesozoic Era. In the experiments conducted at 1300 and 1350°C, the resulting melts have a high Mg# andesite signature, indicating that the melt-peridotite reaction may have played a major role in the generation of high Mg# andesite. Our experimental results support the hypothesis that melts derived from foundered eclogite in the asthenosphere will consume the lithospheric peridotites. Therefore, melt-peridotite reaction is an important mechanism for the destruction/thinning of the lithosphere.

关键词： eclogite peridotite melt/peridotite reaction high Mg# andesite delamination destruction of lithosphere

Synthesis of polyurea from 1,6-hexanediamine with CO_2 through a two-step polymerization

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Green Energy & Environment 2017年第4期2卷 370-376页

作者： shan Jiang Ruhui Shi Haiyang Cheng chao Zhang Fengyu Zhao School of Chemical Engineering Changchun University of Technology State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied Chemistry Chinese Academy of Sciences

Activation and transformation of CO_2 is one of the important issues in the field of green and sustainable chemistry. Herein, CO_2 as a carbonoxygen resource was converted to CO_2-polyurea with 1,6-hexanediamine through a two-step polymerization. The reaction parameters such as temperature, pressure and reaction time were examined; and several kinds of catalysts were screened in the absence and presence of NMP solvent. The formed oligomer and the final polyurea were characterized by FT-IR, VT-DRIFTS, NMR, XRD, AFM and their thermal properties were examined by TGA and DSC. It was confirmed that the final polyurea has a high thermal stability; the melting temperature is 269℃ and the decomposition temperature is above 300℃. It is a brittle polymer with a tensile strength of 18.35 MPa at break length of 1.64%. The polyurea has a stronger solvent resistance due to the ordered hydrogen bond in structure. The average molecular weight should be enhanced in the postpolymerization as the appearance, hydrogen bond intensity, crystallinity, melting point and the thermal stability changed largely compared to the oligomer. The present work provides a new kind of polyurea, it is expected to have a wide application in the field of polymer materials.

关键词： CO2 Polyurea Two-step polymerization Catalysis

Partial organic fertilizer substitution promotes soil multifunctionality by increasing microbial community diversity and complexity

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Pedosphere 2023年第3期33卷 407-420页

作者： Quan TANG Yongqiu XIA chaopu ti Jun shan Wei ZHOU Chenglin LI Xing YAN Xiaoyuan YAN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese academy of Sciences Beijing 100049(China) College of Environmental Science and Engineering Yangzhou UniversityYangzhou 225127(China)

Partial substitution of synthetic nitrogen(N)with organic fertilizers(PSOF)is of great significance in improving soil ecosystem functions in systems that have deteriorated due to the excessive application of chemical N ***,existing studies typically focus on individual soil functions,neglecting the fact that multiple functions occur *** remains unclear how PSOF influences multiple soil functions and whether these impacts are related to soil microbial ***,we examined the impacts of partial substitutions(25%–50%)of chemical N fertilizer with organic form(pig manure or municipal sludge)in a vegetable field on soil multifunctionality,by measuring a range of soil functions involving primary production(vegetable yield and quality),nutrient cycling(soil enzyme activities,ammonia volatilization,N leaching,and N runoff),and climate regulation(soil organic carbon sequestration and nitrous oxide emission).We observed that PSOF improved soil multifunctionality,with a 50%substitution of chemical N fertilizer with pig manure being the best management practice;the result was strongly related to the diversities and network complexities of bacteria and *** forest analysis further revealed that soil multifunctionality was best explained by the bacterial-fungal network complexity,followed by available phosphorus level and bacterial *** PSOF also shifted the composition of bacterial and fungal communities,with increased relative abundances of dominant bacteria phyla,such as Bacteroidetes,Gemmatimonadetes,and Myxococcota,and fungal phyla,such as Basidiomycota and *** observed increases in soil multifunctionality were consistent with significant increases in the relative abundances of keystone taxa such as Blastocladiomycota,Chaetomiaceae,and ***,these findings indicate that PSOF can enhance interactions within and among microbial communities and that such practices have the potential to impro

关键词： bacterial and fungal diversity biogeochemical cycling climate regulation enzyme activity microbial network primary production soil function

The Banded Spherulites of iPP Induced by Pressure Vibration Injection Molding

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Chinese Journal of Polymer Science 2015年第11期33卷 1625-1632页

作者： Ren-xi La Qi-xiong Zhou chao Xia Da-shan Mi 张杰 State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University

Isotactic polypropylene（i PP） samples obtained by pressure vibration injection molding（PVIM） and conventional injection molding（CIM） were studied by polarized-light microscopy（PLM）, respectively. It was found that the alternating bright and dark banded spherulites were generated in the transitional region of PVIM parts. It is the first time that the banded spherulites of isotactic polypropylene were observed in polymer processing. What＇s more, the banded spherulites were proved to be constituted of α-form crystal by hot stage polarized-light microscopy（HT-PLM） and wide angle X-ray diffraction（WAXD）. Morphology of the banded spherulites was also studied by scaning electronical microscopy（SEM）.

关键词： α-Form iPP Banded spherulites Vibration injection molding Oscillatory pressure