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北部湾北部海域夏季浮游细菌空间分布特征及其影响因素

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上海海洋大学学报 2022年第2期31卷 433-444页

作者：何伟东孙鹏飞张秋丰上海海洋大学海洋生态与环境学院上海201306 自然资源部第四海洋研究所广西北海536000

于2020年7月至8月在北部湾北部海域设立50个站位对浮游细菌和环境因子进行调查,探讨浮游细菌空间分布以及对环境因子的响应。研究结果显示:表层浮游细菌丰度变化范围为0.33×10^(5)~91.47×10^(5)cells/mL,平均值为12.61×10^(5)cells/... 详细信息

于2020年7月至8月在北部湾北部海域设立50个站位对浮游细菌和环境因子进行调查,探讨浮游细菌空间分布以及对环境因子的响应。研究结果显示:表层浮游细菌丰度变化范围为0.33×10^(5)~91.47×10^(5)cells/mL,平均值为12.61×10^(5)cells/mL;中层浮游细菌丰度变化范围为0.22×10^(5)~7.48×10^(5) cells/mL,平均值为2.15×10^(5)cells/mL;底层浮游细菌丰度的变化范围为1.76×10^(5)~71.33×10^(5) cells/mL,平均值为17.74×10^(5)cells/mL。浮游细菌丰度在水平方向上呈近岸沿海向远岸深海区域逐渐降低的趋势;垂直方向上浮游细菌丰度与深度相关性不显著(P>0.05),近岸海域浮游细菌丰度在垂直方向上没有明显的趋势,但远岸海域表层和中层丰度接近,底层丰度大于表层和中层的丰度。Pearson相关性分析显示:表层丰度与盐度、pH呈显著负相关(P<0.05),与硝酸盐、亚硝酸盐、硅酸盐呈极显著正相关(P<0.01);中层丰度与温度、磷酸盐呈极显著正相关(P<0.01),与硝酸盐呈显著正相关(P<0.05);底层与铵盐呈显著负相关(P<0.05),这表明浮游细菌的空间分布受到温度、盐度、pH、营养盐等多个环境因子的共同影响。

关键词：浮游细菌丰度分布特征环境因子

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A NEW MEASURING FLEXIBILITY METHODOLOGY——REAL OPTION APPROACH

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A NEW MEASURING FLEXIBILITY METHODOLOGY——REAL OPTION APPRO...

2005年中国机械工程学会年会

作者： he Dezhong, MENG weidong (Graduate school, Chongqing University, Chongqing, 400044 College of Economy and Business Administration, Chongqing University, Chongqing, 400044)

＜正＞Flexibility in manufacturing has become a key strategic aspect of company. Manufacturing flexibility gives the management an ability to change or even reverse the decision made in earlier periods and provides some degree of freedom to take advantage of outcomes better than expected and an ability to reduce losses. These factors including volatility of market demand, number of products , correlation between products as well as capacity constraints all affect the value of flexibility in manufacturing .There are still problems to evaluate and measure flexibility in an appropriate way. The theory of real options, which takes flexibility into account in valuation process, has shown to be an accessible way in measuring flexibility. To have a real option means to have opportunities but no obligations, thereby flexibility can be interpreted as different types of options. After reviewing some of literature on real option theory applied on valuation of manufacturing flexibility, this paper focus on the flexibility related manufacturing on application of real options and interprets different types of flexibility. Based on the comparison with financial options, real options in the flexible manufacturing systems are identified and different types of model of valuing flexibility are proposed.

关键词： real option manufacturing flexibility value

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链式自动化弹仓的设计与仿真

国外电子测量技术 2021年第1期40卷 49-52页

作者：王润鑫陈桦何伟栋西安工业大学兵器科学与技术学院西安710021 西安工业大学机电工程学院西安710021

为降低链式弹仓在运转过程中的冲击载荷,减少多边形效应的影响,使传动更平稳,特采用大齿数链轮和小节距链条的方案来进行弹仓设计,基于Creo对弹架、链轮、箱体、轨道等部件进行三维建模,建立了弹仓的总体结构模型。运用拉格朗日第二类... 详细信息

为降低链式弹仓在运转过程中的冲击载荷,减少多边形效应的影响,使传动更平稳,特采用大齿数链轮和小节距链条的方案来进行弹仓设计,基于Creo对弹架、链轮、箱体、轨道等部件进行三维建模,建立了弹仓的总体结构模型。运用拉格朗日第二类方程建立了弹仓的动力学微分方程,并且结合多体动力学仿真软件RecurDyn对其进行运动学仿真,得到了链式弹仓在启动阶段紧边部件和松边部件的动力学响应。通过对两者的各项运动响应的分析,证明该弹仓传动较为平稳,能够满足设计要求。

关键词：链式弹仓多边形效应 RecurDyn仿真

三齿轮联动双曲柄四环板式针摆行星传动的动力学研究

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制造技术与机床 2011年第10期 152-156页

作者：鲍君华何卫东大连交通大学机械工程学院辽宁大连116028

在Pro/E软件系统下建立完整的三齿轮联动双曲柄四环板式针摆行星减速器虚拟装配实体模型,并基于ADAMS软件环境,对模型进行虚拟样机试验验证;建立了准确的动力学分析模型;完成了几种工况条件下虚拟样机的仿真计算;并结合样机工作性能与... 详细信息

在Pro/E软件系统下建立完整的三齿轮联动双曲柄四环板式针摆行星减速器虚拟装配实体模型,并基于ADAMS软件环境,对模型进行虚拟样机试验验证;建立了准确的动力学分析模型;完成了几种工况条件下虚拟样机的仿真计算;并结合样机工作性能与动力学测试,完成虚拟模型的实验室验证。

关键词：虚拟样机环板式针摆行星传动动力学试验验证

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温州城市总体规划实施评估方法与经验借鉴

规划师 2014年第S3期30卷 281-285页

作者：潘宁宁贺卫东温州市城市规划设计研究院规划设计二所

开展城市总体规划实施评估已成为学界和业界的共识,国内外学者在实施评估方法、体系建立及机制等方面做了许多积极的探索。但在实践中,由于城市的差异,尤其是市场经济发达地区的城市,很难直接应用一般的城市总体规划实施评估体系和方法... 详细信息

开展城市总体规划实施评估已成为学界和业界的共识,国内外学者在实施评估方法、体系建立及机制等方面做了许多积极的探索。但在实践中,由于城市的差异,尤其是市场经济发达地区的城市,很难直接应用一般的城市总体规划实施评估体系和方法。研究结合温州开展的总体规划评估实践,探究市场经济发达地区城市总体规划实施评估的有效途径和方法。

关键词：市场经济总体规划实施评估评估方法温州

Reconstructing forest and grassland cover changes in China over the past millennium

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Science China Earth Sciences 2025年第1期68卷 94-110页

作者： Fanneng he Fan YANG Yafei WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Research Institute of Yellow River Civilization and Sustainable Development Henan University University of Chinese Academy of Sciences

Historical forest and grassland cover changes not only are critical indicators for quantifying ecological and environmental change processes but also serve as fundamental data for long-term climate change simulations and terrestrial ecosystem carbon emission assessments. However, because of limitations in historical data, quantitative estimations and spatially gridded reconstructions of these changes remain challenging, necessitating further methodological exploration. This study focused on China's present-day land area over the past millennium, objectively capturing the characteristics and drivers of forest and grassland cover changes. On this basis, using the forest transition theory and the space-for-time substitution method, we depicted the historical deforestation process as an inverted “S” curve and developed a model to reconstruct historical forest area changes based on the functional relationship between the forest area and population size dynamics. Subsequently, a gridded forest allocation model was established on the basis of deforestation tendencies. For the grassland cover, we implemented regionspecific methods, such as the cropland area deduction method and the habitat constraint method, to quantitatively reconstruct historical changes. Consequently, we obtained provincial forest and grassland area changes over the past millennium and mapped 10-km-resolution gridded data of forest and grassland cover. The results indicated the following.(1) The methods developed using population data as a proxy objectively reproduced the spatiotemporal evolution of forest and grassland cover in China over the past millennium. These feasible methods offer a novel pathway for the quantitative reconstruction of historical forest and grassland cover changes.(2) The data indicated that China's forest area generally decreased over the past millennium, characterized by a “decrease-then-increase” pattern. The forest area experienced three distinct phases: a slow decline(AD 1000

关键词： Land use and land cover change Forest Grassland Quantitative reconstruction Gridded reconstruction China historical period

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AC-600厂房布置

核动力工程 1989年第5期10卷 45-48页

作者：徐长荣和卫东西南反应堆工程研究设计院

本文对 AC-600核电站反应堆厂房和核辅助厂房布置作了简要说明和讨论。

关键词：压水堆核电站厂房总体布置

铸牢中华民族共同体意识下广西抢花炮习俗的发展路径——以靖西市龙邦镇为例

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中华优秀传统文化研究

中华优秀传统文化研究 2023年第1期 77-91页

作者：何卫东广西民族大学体育与健康科学学院

铸牢中华民族共同体意识、引领民俗文化活动,在地方文化建设中发挥着重要的作用。靖西市龙邦镇“关圣祭祀节”和壮族抢花炮赛事项目历史悠久,特色鲜明,文化内涵丰富,吸引了当地各族民众的积极参与。“忠义”精神贯穿该活动及赛事项目始... 详细信息

铸牢中华民族共同体意识、引领民俗文化活动,在地方文化建设中发挥着重要的作用。靖西市龙邦镇“关圣祭祀节”和壮族抢花炮赛事项目历史悠久,特色鲜明,文化内涵丰富,吸引了当地各族民众的积极参与。“忠义”精神贯穿该活动及赛事项目始终,此赛事活动蕴涵诸多美好寓意,民族认同感强,是同根生文化的归属点和铸牢中华民族共同体意识的具体体现,是地方政治、经济和文化的发展缩影。

关键词：习近平文化思想铸牢中华民族共同体意识抢花炮靖西龙邦镇边疆地区民俗体育文化发展路径

Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di Zhang Pengfei Lv Wei Qin Xin he Yuanhua he Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability