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Magnetoelectric Properties of Piezoelectric—Piezomagnetic Composites with Elliptical Nanofibers

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Acta Mechanica Solida Sinica 2020年第3期33卷 368-380页

作者： Ru Tian Jinxi liu xianglin liu Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China Hebei Key Laboratory of Mechanics of Intelligent Materials and Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Based on the surface/interface theory,the effective magnetoelectric(ME)properties of piezoelectric(PE)-piezomagnetic(PM)composites with elliptical nanofibers are investigated *** the complex function theory,conformal mapping and the Mori-Tanaka mean-field method,the solutions of magneto-electro-elastic(MEE)fields are obtained,which satisfy both the interface and the single-valued *** closed-form expression of the ME coefficient of the composites shows that the effect of ME coefficient is related to the interface parameters,elliptical aspect ratio,material properties of both fiber and matrix and the fiber volume *** calculation shows that by properly selecting some of these parameters,the effective ME coefficient could be substantially enhanced.

关键词： Surface/interface effect Effective magnetoelectric coefficient Elliptical nanofiber Piezoelectric Piezomagnetic

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意图驱动数据链网络策略协商模型与算法

系统工程与电子技术 2024年第6期46卷 2128-2137页

作者：刘祥林杨春刚李富强欧阳颖宋延博西安电子科技大学通信工程学院陕西西安710071 中国电子科技集团公司数据链技术重点实验室陕西西安710068

针对意图驱动数据链网络中多条意图策略冲突问题,提出一种基于优先级的意图协商算法,实现网络资源受限条件下意图策略最优配置。所提算法综合考虑时间、带宽两个维度的资源,通过回收已配置低优先级意图资源间接增多可用的网络资源,提高... 详细信息

针对意图驱动数据链网络中多条意图策略冲突问题,提出一种基于优先级的意图协商算法,实现网络资源受限条件下意图策略最优配置。所提算法综合考虑时间、带宽两个维度的资源,通过回收已配置低优先级意图资源间接增多可用的网络资源,提高待配置高优先级意图业务质量。同时,利用最优化求解得到待配置高优先级意图、被回收低优先级意图的最佳资源分配方式,避免意图因资源不足强行降级而导致服务质量急剧下降的问题。实验结果表明,所提算法提高了数据链网络资源规划能力,相较于已有的协商算法,在意图服务质量上有6.0%和5.5%的提升。

关键词：意图驱动网络资源分配意图协商网络架构数据链网络

Effects of zinc on χ-Fe_(5)C_(2) for carbon dioxide hydrogenation to olefins:Insights from experimental and density function theory calculations

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Chinese Journal of Chemical Engineering 2023年第2期54卷 206-214页

作者： xianglin liu Minjie Xu Chenxi Cao Zixu Yang Jing Xu State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Maoming Branch R&D Institute SINOPECMaoming 525000China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Production of light olefins from CO_(2), the primary greenhouse gases, is of great importance to mitigate the adverse effects of CO_(2) emission on environment and to supply the value-added products from nonpetroleum resource. However, development of robust catalyst with controllable selectivity and stability remains a challenge. Herein, we report that Zn-promoted Fe catalyst can boost the stable and selective production of light olefins from CO_(2). Specifically, the Zn-promoted Fe exhibits a highly stable activity and olefin selectivity over 200 h time-on-stream compared to the unpromoted Fe catalyst, primarily owing to the preservation of active χ-Fe_(5)C_(2) phase. Structural characterizations of the spent catalysts suggest that Zn substantially regulates the content of iron carbide on the surface and suppresses the reoxidation of bulk iron carbide during the reaction. DFT calculations confirm that adsorption of surface carbon atoms and graphene-like carbonaceous species are not thermochemically favored on Zn-promoted Fe catalyst. Carbon deposition by CAC coupling reactions of two surface carbon atoms and dehydrogenation of CH intermediate are also inhibited. Furthermore, the effects of Zn on antioxidation of iron carbide were also investigated. Zn favored the hydrogenation of surface adsorbed oxygen atoms to H_(2)O and the desorption of H_(2)O, which reduces the possibility of surface carbide being oxidized by the chemisorbed oxygen.

关键词： Reaction engineering χ-Fe_(5)C_(2) Zn promoter Carbon dioxide Hydrogenation Density function theory

Quality assessment of onboard GPS receiver and its combination with DORIS and SLR for Haiyang 2A precise orbit determination

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Science China Earth Sciences 2015年第1期58卷 138-150页

作者： GUO Jing ZHAO QiLe GUO Xiang liu xianglin liu JingNan ZHOU Quan GNSS Research Center Wuhan University School of Geodesy and Geomatics Wuhan University Fugro Intersite B.V. Leidschendam 2263HWNetherlands Collaborative Innovation Center of Earth and Space Science Wuhan University Test and Assessment Research Center China Satellite Navigation Office

The GPS,DORIS,and SLR instruments are installed on Haiyang 2A(HY2A)altimetry satellite for Precise Orbit Determination(POD).Among these instruments,the codeless GPS receiver is the state-of-art Chinese indigenous onboard receiver,and it is the first one successfully used for Low Earth Orbit(LEO)***,the contribution assesses the performance of the receiver through an analysis of data integrity,numbers of all tracked and valid measurements as well as multipath *** receiver generally shows good performance and quality despite a few *** example,L2 observations are often missing in low elevations,particularly during the ascent of GPS satellites,and the multipath errors of P1 show a slightly abnormal ***,the PCO(Phase Center Offset)and PCV(Phase Center Variation)of the antenna of the GPS receiver are determined in this contribution.A significant leap for Z-component of PCO up to-1.2 cm has been found on 10 October ***,the obtained PCO and PCV maps are used for GPS only POD *** post-fit residuals of ionosphere-free phase combinations reduce almost 50%,and the radial orbit differences with respect to CNES(Centre National d’Etudes Spatiales)Precise Orbit Ephemeris(POEs)improve about 13.9%.The orbits are validated using the SLR data,and the RMS of SLR Observed minus Computed(O-C)residuals reduces from 17.5 to 15.9 *** improvements are with respect to the orbits determined without PCO and ***,six types of solutions are determined for HY2A satellite using different combinations of GPS,DORIS,and SLR *** of SLR O-C residuals and cross-comparison of orbits obtained in the contribution and the CNES POEs indicate that the radial accuracy of these orbits is at the 1.0 cm level for HY2A orbit solutions,which is much better than the scientific requirements of this *** is noticed that the GPS observations dominate the achievable accuracy of POD,and the combination of multiple types of observation

关键词： Haiyang 2A GPS receiver multipath precise orbit determination phase center offset phase center variations DORIS SLR

Transfer of a eubacteria-type cell division site-determining factor CrMinD gene to the nucleus from the chloroplast genome in Chlamydomonas reinhardtii

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Chinese Science Bulletin 2007年第18期52卷 2514-2521页

作者： liu WeiZhong HU Yong ZHANG RunJie ZHOU WeiWei ZHU JiaYing liu xianglin HE YiKun College of Life Science Capital Normal University Beijing 100037 China College of Life Science Shanxi Normal University Linfen 041004 China College of Life Science Shanxi Normal University Linfen 041004 China

MinD is a ubiquitous ATPase that plays a crucial role in selection of the division site in eubacteria, chloroplasts, and probably Archaea. In four green algae, Mesostigma viride, Nephroselmis olivacea, Chlorella vulgaris and Prototheca wickerhamii, MinD homologues are encoded in the plastid genome. However, in Arabidopsis, MinD is a nucleus-encoded, chloroplast-targeted protein involved in chloro- plast division, which suggests that MinD has been transferred to the nucleus in higher land plants. Yet the lateral gene transfer (LGT) of MinD from plastid to nucleus during plastid evolution remains poorly understood. Here, we identified a nucleus-encoded MinD homologue from unicellular green alga Chlamydomonas reinhardtii, a basal species in the green plant lineage. Overexpression of CrMinD in wild type E. coli inhibited cell division and resulted in the filamentous cell formation, clearly demon- strated the conservation of the MinD protein during the evolution of photosynthetic eukaryotes. The transient expression of CrMinD-egfp confirmed the role of CrMinD protein in the regulation of plastid division. Searching all the published plastid genomic sequences of land plants, no MinD homologues were found, which suggests that the transfer of MinD from plastid to nucleus might have occurred be- fore the evolution of land plants.

关键词：衣藻叶绿体 CrMinD基因基因转移植物进化

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基于HAND的流域洪水淹没快速分析技术

水文 2024年第2期44卷 57-65页

作者：王述强吕凯刘祥林师鹏飞肖家清郝晓博信江饶河水文水资源监测中心江西上饶334000 水灾害防御全国重点实验室河海大学江苏南京210098 长江保护与绿色发展研究院江苏南京210098 河海大学水文水资源学院江苏南京210098 北京金水信息技术发展有限公司北京100000 福建省水利水电勘测设计研究院有限公司福建福州350001

快速分析计算流域洪水淹没,对于防洪具有重要作用,而基于水动力学模型的经典淹没算法在时效性方面存在不足,制约防洪“四预”功能实现和数字孪生流域建设。针对此,本文建立了基于HAND(Height Above Nearest Drainage)的形态淹没模型,用... 详细信息

快速分析计算流域洪水淹没,对于防洪具有重要作用,而基于水动力学模型的经典淹没算法在时效性方面存在不足,制约防洪“四预”功能实现和数字孪生流域建设。针对此,本文建立了基于HAND(Height Above Nearest Drainage)的形态淹没模型,用于快速分析流域洪水淹没情况,在乐安河流域上游进行了应用验证。结果表明,模型可在5秒内完成洪水淹没计算,对四场历史洪水和三场设计洪水淹没范围的总体模拟精度平均为0.95,达到水动力学模型的模拟精度;对淹没水深的模拟存在较大误差,平均误差为0.79 m。基于HAND的形态淹没模型可快速绘制全流域洪水淹没范围图,大幅提升影响预报和防洪预演的时效性水平。

关键词： HAND 形态淹没模型洪水淹没分析 HEC-RAS模型

Water storage variations of the Yangtze,Yellow,and Zhujiang river basins derived from the DEOS Mass Transport (DMT-1) model

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Science China Earth Sciences 2011年第5期54卷 667-677页

作者： ZHAO QiLe liu xianglin Pavel DITMAR Christian SIEMES Elena REVTOVA Hassan HASHEMI-FARAHANI Roland KLEES Delft Institute of Earth Observation and Space Systems (DEOS) Faculty of Aerospace Engineering Delft University of Technology Kluverweg 1 2629 HS Delft the Netherlands GNSS Research Center Wuhan University Wuhan 430079 China

In general, China is short of water resources and some regions even experience a shortage of daily water supply. This could threaten the stability and economic development of the nation. A study on the water storage variations is especially important for the water management and storage prediction in three largest river basins of China, namely, Yangtze, Yellow, and Zhujiang, where the most dense population and leading economic regions are located. The satellite gravity mission GRACE （Gravity Recovery and Climate Experiment） provides an opportunity to macroseopically identify water （or mass） variations in the Earth＇s system with a spatial resolution of 300-400 km and a temporal resolution of about one month. We use the first release of the DEOS （Delft Institute of Earth Observation and Space Systems） Mass Transport （DMT-1） model based on GRACE data to analyze water storage changes in the three river basins. The DMT-1 model consists of monthly solutions, which are computed using an innovative methodology. The methodology includes, in particular, the application of a statistically optimal Wiener-type filter based on full varianee-covariance matrices of noise and signal. This results in particularly sharp mass variation maps. Taking one monthly solution as an example, we compare the results derived from the DMT-1 model with ones produced with the standard post-processing scheme based on a combination of the de-striping and Gaussian filtering. The comparison shows that the DMT-1 model outperforms the other models and is suitable for the analysis of the mass changes in river basins. A subset of the DMT-1 solutions in the interval between February 2003 and May 2008 is used to estimate the secular trends and seasonal variations for the three river basins. The estimated trends show that the water storage of the Yellow River basin does not have significant changes, while the Zhujiang and Yangtze river basins have a large and statistically significant water storage increase. T

关键词： GRACE DMT-1 water storage variation equivalent water layer thickness Yangtze-Yeilow-Zhujiang river basins secular and seasonal variation

Toxic effects of three perfluorinated or polyfluorinated compounds(PFCs)on two strains of freshwater algae:Implications for ecological risk assessments

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Journal of Environmental Sciences 2023年第9期131卷 48-58页

作者： Liangliang Zhang Xiaowei Zheng xianglin liu Jue Li Yanyao Li Zeming Wang Nan Zheng Xiangrong Wang Zhengqiu Fan Department of Environmental Science and Engineering Fudan UniversityShanghai 200433China Laboratory of Industrial Water and Ecotechnology Department of Green Chemistry and TechnologyGhent UniversityKortrijk 8500Belgium Jinan Environmental Research Academy Jinan 250102China

Perfluorinated or polyfluorinated compounds(PFCs)continue entering to the environmental as individuals or mixtures,but their toxicological information remains largely ***,we investigated the toxic effects and ecological risks of Perfluorooctane sulfonic acid(PFOS)and its substitutes on prokaryotes(Chlorella vulgaris)and eukaryotes(Microcystis aeruginosa).Based on the calculated EC50 values,the results showed that PFOS was significantly more toxic to both algae than its alternatives including Perfluorobutane sulfonic acid(PFBS)and 6:2 Fluoromodulated sulfonates(6:2 FTS),and the PFOS-PFBS mixture was more toxic to both algae than the other two PFC *** action mode of binary PFC mixtures on Chlorella vulgaris was mainly shown as antagonistic and on Microcystis aeruginosa as synergistic,by using Combination index(CI)model coupled with Monte Carlo *** mean risk quotient(RQ)value of three individual PFCs and their mixtures were all below the threshold of 10^(−1),but the risk of those binary mixtures were higher than that of PFCs individually because of their synergistic *** findings contribute to enhance the understanding of the toxicological information and ecological risks of emerging PFCs and provide a scientific basis for their pollution control.

关键词： Toxicity Combination index model Monte Carlo simulation Action mode Algae

Promotional effects of Sb on Pd-based catalysts for the direct synthesis of hydrogen peroxide at ambient pressure

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Chinese Journal of Catalysis 2018年第4期39卷 673-681页

作者： Doudou Ding Xingyan Xu Pengfei Tian xianglin liu Jing Xu Yi‐Fan Han State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Research Center of Heterogeneous Catalysis and Engineering Science School of Chemical Engineering and EnergyZhengzhou UniversityZhengzhou 450001HenanChina

TiO2‐supported Pd‐Sb bimetallic catalysts were prepared and evaluated for the direct synthesis of H2O2 at ambient *** addition of Sb to Pd significantly enhanced catalytic performance,and a Pd50Sb catalyst showed the greatest selectivity of up to 73%.Sb promoted the dispersion of Pd on TiO2,as evidenced by transmission electron microscopy and X‐ray diffraction.X‐ray photoelectron spectroscopy indicated that the oxidation of Pd was suppressed by *** addition,Sb2O3 layers were formed and partially wrapped the surfaces of Pd catalysts,thus suppressing the activation of H2 and subsequent hydrogenation of *** situ diffuse reflection infrared Fourier transform spectroscopy for CO adsorption suggested that Sb homogenously located on the surface of Pd‐Sb catalysts and isolated contiguous Pd sites,resulting in the rise of the ratio of Pd monomer sites that are favorable for H2O2 *** a result,the Sb modified Pd surfaces significantly enhanced the non‐dissociative activation of O2 and H2O2 selectivity.

关键词： Bimetallic catalyst Hydrogen peroxide Palladium Antimony Direct synthesis