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光照与浮游动物耦合作用对浮游植物群落的影响——以小兴凯湖为例

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湿地科学 2024年第2期22卷 227-235页

作者：董向前袁宇翔路永正武海涛侯璐蔡羽曼朱晓艳吉林建筑大学松辽流域水环境教育部重点实验室吉林长春130118 中国科学院湿地生态与环境重点实验室中国科学院东北地理与农业生态研究所吉林长春130102

光照是浮游植物光合作用必需的能源,浮游动物是浮游植物的重要捕食者,二者直接影响浮游植物的生长,然而光照与捕食胁迫耦合作用下浮游植物群落结构的响应特征仍不清楚。2022年8月中旬,采集小兴凯湖原位水样,通过室内培养实验,模拟研究... 详细信息

光照是浮游植物光合作用必需的能源,浮游动物是浮游植物的重要捕食者,二者直接影响浮游植物的生长,然而光照与捕食胁迫耦合作用下浮游植物群落结构的响应特征仍不清楚。2022年8月中旬,采集小兴凯湖原位水样,通过室内培养实验,模拟研究了光照变化和浮游动物捕食胁迫下浮游植物群落组成与生长的响应特征。结果表明,浮游植物丰度与光照强度存在线性关系,而且浮游植物丰度对光照强度变化的响应存在一定的滞后性。浮游动物的存在降低了浮游植物群落的生物多样性,但增加了水华藻类铜绿微囊藻(Microcystis aeruginosa)的竞争优势。本研究结果有助于深入了解湖泊生态系统中浮游植物对环境变化的响应机制,为全面推进兴凯湖水华防治与可持续管理提供科学依据。

关键词：光照浮游动物浮游植物水华

Fabrication of Ni-, Co- and NiCo-coated Graphite Microspheres by Heterogeneous Precipitation

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 397-401页

作者：周建新沈湘黔 School of Materials Science and Engineering Jiangsu University

The precursors with NiCO3.2Ni（OH）2.2H2O, Co2（OH）2CO3, or both NiCO3.2Ni（OH）2.2H2O and Co2（OH）2CO3 coated graphite microspheres were prepared respectively by the aqueous heterogeneous precipitation using nickel sulfate, cobalt nitrate, sodium carbonate, ammonium bicarbonate and graphite microspheres as the main starting materials. Subsequently, Ni-, Co- and NiCo-coated graphite microspheres were successfully obtained by thermal reduction of the as-prepared precursors at 500 ℃ for 2 h, respectively. These metal-coated graphite microspheres were characterized with a smooth, cohesive surface consisting of fine metallic particles. Optimized precipitation processing parameters of the concentration of graphite microspheres （10 g/L）, the rate of adding reactants （3 mL/min） and pH value （8.0） were determined by a trial and error method. The thermal analysis of the precursors was investigated by TG. Powders of the precursors and the resultant metal-（Ni, Co and NiCo alloy） coated graphite microspheres were characterized by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）.

关键词： graphite microsphere metal-coated heterogeneous precipitation lithium ion battery

揭示曝气模式影响营养盐去除及污泥特征的机制

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水处理技术 2023年第2期49卷 66-69,80页

作者：董向前张博山西水利职业技术学院山西运城044004 中北大学仪器与电子学院山西太原030051

设置了不同曝气方式,考察了运行模式(连续和间歇)对低表观气速好氧颗粒污泥(AGS)处理城镇低C/N废水过程中污泥特征及污染物去除规律的影响。研究表明,间歇曝气利于AGS的快速形成及污染物的去除。间歇曝气运行时AGS内污泥浓度混合液悬浮... 详细信息

设置了不同曝气方式,考察了运行模式(连续和间歇)对低表观气速好氧颗粒污泥(AGS)处理城镇低C/N废水过程中污泥特征及污染物去除规律的影响。研究表明,间歇曝气利于AGS的快速形成及污染物的去除。间歇曝气运行时AGS内污泥浓度混合液悬浮固体(MLSS)高达5.1~5.6 g/L,挥发性悬浮固体(VSS)/MLSS为0.72~0.75,粒径为741~758μm,均高于连续曝气组别。此外,间歇曝气提高了AGS内胞外聚合物(EPS)含量提高至57.6 mg/g,其中蛋白质(PN)含量变化不明显而多糖(PS)含量增加显著。EPS含量提高提高了AGS的机械强度。间歇曝气能提高AGS对化学需氧量(COD)、总氮(TN)及总磷(TP)的去除,且稳定时期去除率分别高达94.6%~95.2%、82.5%~85.3%和86.5%~89.5%,均高于连续曝气组别。典型周期研究发现间歇曝气提高了AGS对COD的去除及厌氧期TP的释放,提高了微生物的代谢活性。

关键词：曝气方式颗粒污泥低C/N废水污泥特征污染物去除

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang GUO Wenqing YANG Yuanbo dong dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

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锥盘式颗粒肥撒施机构抛撒性能分析与试验

农业工程学报 2013年第19期29卷 33-40页

作者：董向前宋建农张军奎康小军王继承中国农业大学工学院北京100083

为了提高颗粒肥撒施的均匀性和一致性,该文设计了一种锥盘式撒肥机构,通过对锥盘式撒肥机构工作性能的分析,建立了肥料颗粒的受力方程。通过撒肥试验,研究喂入区大小、甩盘转速、甩肥高度对撒肥区域内肥料分布规律的影响。试验结果表明... 详细信息

为了提高颗粒肥撒施的均匀性和一致性,该文设计了一种锥盘式撒肥机构,通过对锥盘式撒肥机构工作性能的分析,建立了肥料颗粒的受力方程。通过撒肥试验,研究喂入区大小、甩盘转速、甩肥高度对撒肥区域内肥料分布规律的影响。试验结果表明:喂入区大小对肥料颗粒的横向幅宽分布影响较大,对纵向分布影响较小,施肥作业中合理的喂入角为75°;随着甩盘转速的增加,有效施肥区域的横向幅宽和纵向距离均逐渐增大,而且施肥的均匀性和一致性也不断提高,合理转速为600 r/min;施肥高度对施肥幅宽分布和一致性没有显著影响。研究结果可为颗粒肥撒施机的设计提供参考。

关键词：农作物肥料机构旋转锥盘肥料撒施

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Web网络大数据的聚类中心调度技术研究

现代电子技术 2017年第24期40卷 25-27页

作者：肖铮董祥千赵文革成都东软学院四川成都611844

针对传统调度方法一直存在调度精度不准确的问题,提出一种Web网络大数据的聚类中心调度技术的研究方案。针对Web网络大数据重新建立调度模型有效的对数据进行识别,优化聚类中心的K-means算法,解决对大数据调度能力差的问题,提高聚类中... 详细信息

针对传统调度方法一直存在调度精度不准确的问题,提出一种Web网络大数据的聚类中心调度技术的研究方案。针对Web网络大数据重新建立调度模型有效的对数据进行识别,优化聚类中心的K-means算法,解决对大数据调度能力差的问题,提高聚类中心的大数据调度能力,最后使用建立调度模型完成在Web网络大数据环境下的聚类中心数据调度。设计对比仿真试验,通过实验数据可以有效地证明Web网络大数据的聚类中心调度技术的有效性。

关键词： web网络大数据聚类中心调度技术数据识别数据调度

Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 43-53页

作者： dong Ma Qinhui Wang State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by ***,the PG decomposition temperature remains high and the product yield remains *** adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be ***,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic ***,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same *** effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting ***,the reaction mechanism is *** is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition *** example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) *** process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed.

关键词： Phosphogypsum Sulfur dioxide Copper slag Fluidized-bed Reduction Waste treatment

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： Chi Ma Dianbiao dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

Resilient control of flexible hypersonic vehicles against unmatched distributed faults

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Chinese Journal of Aeronautics 2024年第5期37卷 60-70页

作者： dong ZHAO Wenjing REN School of Artificial Intelligence Anhui UniversityHefei 230601China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

This paper studies a robust fault compensation and vibration suppression problem of flexible hypersonic *** controlled plant is represented by a cascade system composed of a nonlinear Ordinary Differential Equation(ODE)and an Euler-Bernoulli Beam Equation(EBBE),in which the vibration dynamics is coupled with the rigid dynamics and suffers from distributed faults.A state differential transformation is introduced to transfer distributed faults to an EBBE boundary and a longitudinal dynamics is refined by utilizing T-S fuzzy IF-THEN rules.A novel T-S fuzzy based fault-tolerant control algorithm is developed and related stability conditions are *** robust exponential stability and well-posedness are proved by using the modified l_(0)-semigroup based Lyapunov direct approach.A simulation study on the longitudinal dynamics of flexible hypersonic vehicles effectively verifies the validity of the developed theoretical results.

关键词： Flexible hypersonic vehicles ODE-EBBE cascade Robust exponential stability Unmatched distributed fault compensation Vibration suppression