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Corrosion behavior of laser-clad coatings fabricated on Ti6Al4V with different contents of TaC addition

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Rare Metals 2020年第4期39卷 436-447页

作者： Lie-feng Hu Jun Li Ying-Hao Lv Yang-feng tao School of Materials Engineering Shanghai University of Engineering ScienceShanghai 201620China

The coatings were produced on Ti6A14V by lasercladding the mixture of Ni-based alloy and different contents of TaC(0 wt%,5 wt%,10 wt%,20 wt%,30 wt%,40 wt%).The microstructure and corrosion behavior of the coatings were investigated in *** coating without TaC is composed of TiNi/Ti2Ni(matrix)and TiC/TiB/TiB2(reinforcement).Moreover,TaC is precipitated again and TiC/TiB/TiB2 solid solutions containing Ta are formed in the *** potential of the coatings(-0.639,-0.636,-0.547,-0.534,-0.471 and-0.348 V)increases,and passive current density(1×10-5.4,1×10-5.6,1×10-6.4,1×10-6.8,1×10-6.7 and 1×10-6.9 A·cm-2)*** passive films are more difficult to break down(breakdown potential of 0.003,0.080,0.204 and 0.605 V).When the content of TaC exceeds 20 wt%,no breakdown phenomenon is *** passive film on the surface of coating without TaC is mainly composed of TiO2,Al2O3,Cr2O3,CrO3,NiO,Ni2O3 and *** the addition of TaC,Ta2O5 is formed in the passive *** content of Ta2O5 presents an increasing trend with the increase in the content of *** addition of TaC has a positive effect on corrosion resistance of the coatings.

关键词： Laser cladding Coating Microstructural evolution Corrosion resistance

Simple Minimum(K_4-e)-coverings of Complete Multipartite Graphs

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Acta Mathematica Sinica,English Series 2019年第5期35卷 632-648页

作者： Yu feng GAO Yan Xun CHANG tao feng Institute of Mathematics Beijing Jiaotong University College of Mathematics Tonghua Normal University

A decomposition of K_(n(g))∪Γ, the complete n-partite equipartite graph over gn vertices union a graph Γ(called the excess) that is a subgraph of K_(n(g)), into edge disjoint copies of a graph G is called a simple minimum group divisible covering of type g^n with G if Γ contains as few edges as possible. We examine all possible excesses for simple minimum group divisible(K_4-e)-*** and sufficient conditions are established for their existence.

关键词： Group divisible covering (K4-e)-covering excess graph

The Effects of Metal Ions and Secondary Ligands on the Formation of Structures Resulted from Flexible Building Blocks

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1462-1467页

作者： LI feng LI tao-Hai CAO Rong State Key Laboratory of Structural Chemistr3 Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fujian Fuzhou 350002 China

Two coordination polymers have been synthesized from cpg/4,4＇-bipy/metal ions reaction system, [Zn（cpg）（4,4＇-bipy）0.5（H2O）]·H2O 1 and [Cd（cpg）（4,4＇-bipy）0.5（H2O）2]·H2O 2. X- ray analyses show that different coordination geometries of zinc and cadmium ions lead to similar ladder structures （tetra-for zinc ion and hexa- for cadmium ion）, in which all the flexible cpg molecules exist as single conformations of anti-form.

关键词： hydrothermal synthesis flexible ligand prediction

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挖掘机回转特性分析与优化

液压气动与密封 2024年第2期44卷 15-20页

作者：王飞冯涛嵇秋池徐州徐工挖掘机械有限公司江苏徐州221001 中国矿业大学机电工程学院江苏徐州221001

针对某型挖掘机市场作业出现回转启动抖动、制动锁不住现象,进行厂内回转试验研究。考虑液压因素所致,故搭建试验平台,采集回转马达压力,陀螺仪采集回转运动过程中的角速度、角加速度以及制动时间、制动角度,振动传感器采集驾驶室悬置... 详细信息

针对某型挖掘机市场作业出现回转启动抖动、制动锁不住现象,进行厂内回转试验研究。考虑液压因素所致,故搭建试验平台,采集回转马达压力,陀螺仪采集回转运动过程中的角速度、角加速度以及制动时间、制动角度,振动传感器采集驾驶室悬置主被动侧加速度信号,评估回转支承抖动对驾驶室悬置隔振性能的影响,进而研究驾驶室噪声。结果表明,试验样机振动噪声性能较好,工作装置单动作、回转性能与高端机型差距不大,铲斗内收单动作时间增加16.0%,斗杆内收时间增加13.3%,动臂提升加回转时间增加14.6%,液压缸行程减小9.6%,铲斗提升高度下降7.9%,装车高度稍低。提出的试验方法可以建立切向力与回转角度关系,解决试验之前拉力计需与铲斗回转方向共线的问题。采用PID控制方法,优化压力波动范围,使得回转过程中稳定性好,抖动现象有所改善。

关键词：回转试验平台试验方法 PID

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馒头挥发性风味物质研究进展

食品科学 2024年第8期45卷 312-320页

作者：付元哲黄雅玲冯涛孙敏姚凌云王化田宋诗清上海应用技术大学香料香精技术与工程学院上海201418

馒头是中国传统主食之一,具有1 700多年的历史。随着人们生活质量的不断提高,馒头种类更加丰富,风味需求也变得越来越重要。愉悦的风味成为人们消费的主要驱动力,这对工业化酵母馒头的风味提出了更高的要求。影响馒头风味形成的因素有很... 详细信息

馒头是中国传统主食之一,具有1 700多年的历史。随着人们生活质量的不断提高,馒头种类更加丰富,风味需求也变得越来越重要。愉悦的风味成为人们消费的主要驱动力,这对工业化酵母馒头的风味提出了更高的要求。影响馒头风味形成的因素有很多,包括发酵剂种类、原料以及加工工艺等。其中不同发酵剂因所含微生物的种类及数量不同,对馒头风味形成有显著的影响。本文针对现阶段影响馒头风味的主要因素进行综述,为馒头风味的理论研究提供一定的参考,为开发适应工业化生产且风味更佳的馒头提供实践指导。

关键词：馒头风味发酵剂微生物菌群发酵原料发酵工艺

Microwave-assisted synthesis of diaryl or aryl-alkyl sulfones without catalyst

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Chinese Chemical Letters 2009年第1期20卷 17-20页

作者： Jiong Zou feng Li feng Gang tao Department of Chemistry Fudan University Shanghai 200433 China

The microwave-assisted coupling reaction of electrondeficient aryl halides with sulfinic acid salts through SNAr-based addition reactions within 5-30 min. No catalysts were required under our conditions.

关键词： Microwave Sulfone SNAr-based addition reaction

Tropical cyclones and multiscale climate variability: The active western North Pacific typhoon season of 2018

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Science China Earth Sciences 2020年第1期63卷 1-11页

作者： Liang WU Hongjie ZHANG tao feng Yulian TANG Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100190China College of Oceanography Hohai UniversityNanjing 210098China

The 2018 typhoon season in the western North Pacific(WNP) was highly active, with 26 named tropical cyclones(TCs) from June to November, which exceeded the climatological mean(22) and was the second busiest season over the past twenty years. More TCs formed in the eastern region of the WNP and the northern region of the South China Sea(SCS). More TCs took the northeast quadrant in the WNP, recurving from northwestward to northward and causing heavy damages in China's Mainland(69.73 billion yuan) in 2018. Multiscale climate variability is conducive to an active season via an enhanced monsoon trough and a weakened subtropical high in the WNP. The large-scale backgrounds in 2018 showed a favorable environment for TCs established by a developing central Pacific(CP) El Ni?o and positive Pacific meridional mode(PMM)episode on interannual timescales. The tropical central Pacific(TCP) SST forcing exhibits primary control on TCs in the WNP and large-scale circulations, which are insensitive to the PMM. During CP El Ni?o years, anomalous convection associated with the TCP warming leads to significantly increased anomalous cyclonic circulation in the WNP because of a Gill-type Rossby wave response. As a result, the weakened subtropical high and enhanced monsoon trough shift eastward and northward, which favor TC genesis and development. Although such increased TC activity in 2018 might be slightly suppressed by interdecadal climate variability, it was mostly attributed to the favorable interannual background. In addition, high-frequency climate signals,such as intraseasonal oscillations(ISOs) and synoptic-scale disturbances(SSDs), interacted with the enhanced monsoon trough and strongly modulated regional TC genesis and development in 2018.

关键词： Tropical cyclone Multiscale climate variability Typhoon season of 2018 Western North Pacific

Global dynamics of deterministic and stochastic epidemic systems with nonmonotone incidence rate

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International Journal of Biomathematics 2018年第8期11卷 107-130页

作者： tao feng Zhipeng Qiu Nanjing University of Science and Technology Nanjing 210094 P. R. China

This paper is devoted to studying the dynamics of a susceptible-infective-latent-infective (SILI) epidemic model that is subject to the combined effects of environmental noise and intervention strategy. We extend the classical SILI epidemic model from a deterministic framework to a stochastic one. For the deterministic case, the global stability analysis of the solution is carried out in terms of the basic reproduction number. For the stochastic case, sufficient conditions for the extinction of diseases are obtained. Then, the existence of stationary distribution and asymptotic behavior of the solution are further studied to illustrate the cycling phenomena of recurrent diseases. Numerical simulations are conducted to verify these analytical results. It is shown that both stochastic noise and intervention strategy contribute to the control of diseases.

关键词： SILI epidemic model stochastic asymptotic stability stationary distribution extinction intervention strategy

基于SD-PLUS耦合模型的陕西省土地利用变化及碳储量多情景预测

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水土保持学报 2024年第3期38卷 195-206,215页

作者：李倩王成军冯涛杜传甲张炳林西安建筑科技大学管理学院西安710055 陕西省矿产地质调查中心西安710068

[目的]为探讨不同土地利用方式对区域生态系统碳储量的影响。[方法]以陕西省为研究对象,利用SD-PLUS耦合模型,采用国际耦合模式比较计划第6阶段(CMIP6)提出的耦合共享社会经济路线和代表性浓度路线(SSP-RCP)情景,对2030年陕西省的土地... 详细信息

[目的]为探讨不同土地利用方式对区域生态系统碳储量的影响。[方法]以陕西省为研究对象,利用SD-PLUS耦合模型,采用国际耦合模式比较计划第6阶段(CMIP6)提出的耦合共享社会经济路线和代表性浓度路线(SSP-RCP)情景,对2030年陕西省的土地利用变化进行预测,然后利用InVEST模型模拟未来不同情景下陕西省碳储量及其空间分布。[结果](1)对构建的SD模型进行历史检验,其误差<5%,PLUS模型模拟的2020年土地利用Kappa指数为0.86,模型精度和可靠性总体符合要求;(2)3种情景下,未来建设用地面积均增加,增长速率从低到高的情景分别为SSP126、SSP245、SSP585;在所有情景下,林地面积均增加,水域面积均保持稳定;草地面积在SSP126情景下有小幅度增加,其他情景下减少;耕地面积3种情景下均减少;(3)3种情景下,陕西省碳储量均减少,关中平原建设用地的扩张占用大量的耕地是造成陕西省碳储量下降的主要原因。[结论]在SSP126情景下,建设用地扩张所占用的生态用地面积最小,碳储量损失最少,该情景同时考虑社会经济发展及生态保护的需要,可为未来陕西省国土资源保护和高质量发展提供参考模式。

关键词：土地利用变化 SD-PLUS耦合模型未来情景预测碳储量 InVEST模型

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