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Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River

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Journal of Ocean University of China 2024年第2期23卷 455-466页

作者： LIU Xiao JIANG Xueyan LIU Qian SUI Juanjuan zou Li Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Earth Sciences University of BristolBristolBS81RJUK North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao 266033China Key Laboratory of Ecological Prewarning Protection and Restoration of Bohai SeaMinistry of Natural ResourcesQingdao 266033China Key Laboratory of Marine Environment and Ecology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water ***-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water *** dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human ***,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during *** addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM *** the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS *** resuspension inhibits microbial activities and reduces the production of autochthonous ***,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment.

关键词： chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties

Simulation of the L-valve in the circulating fluidized bed with a coarse-grained discrete particle method

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Particuology 2024年第7期90卷 266-280页

作者： Ruixiang Tang Zheng zou Ji Xu Junwu Wang Qingshan Zhu Hongzhong Li State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesP.O.Box 353Beijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing100190China

Stable and controllable solid flow is essential in circulating fluidized bed (CFB) systems. The L-valve is a typical non-mechanical valve that can provide flexible solid feeding. The investigation of the solid circulation rate and the hydrodynamic characteristics of the L-valve is crucial to its design and operation. The gas-solid flow in the L-valve of a full-loop CFB is studied with the coarse-grained discrete particle method (EMMS-DPM). Good agreements on the solid circulation rate and the pressure drop through the L-valve are achieved between the simulated and experimental data. The solid circulation rate increases linearly with the aeration velocity until the stable particle circulation of the CFB is destroyed. The flow patterns in the horizontal section of L-valve are gas-solid slug flow above the stationary solid layer and the moving solid layer, respectively. The effects of L-valve geometric parameters on the solid flow characteristics are also investigated. The results indicate that reducing the diameter and length of the horizontal section of L-valve can improve the solid transport efficiency, especially at low aeration velocity. Besides, the solid conveying capacity and flow stability are improved when the sharp bend of L-valve is modified to be a gradual bend.

关键词： L-valve Circulating fluidized bed Full loop Discrete particle method Gas-solid flow

基于安全边界保护法的非线性系统自适应安全跟踪控制

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控制与决策 2024年第9期39卷 3023-3032页

作者：李小华邹嵩楠辽宁科技大学电子与信息工程学院辽宁鞍山114051

为解决因实际输出约束突变而与期望轨迹发生冲突所引起的系统跟踪的安全性问题,针对一类具有未知控制方向、未建模动态及时滞的不确定非线性系统,提出一种自适应安全跟踪控制策略.基于一种新的预设有限时间性能函数(prescribed finite-t... 详细信息

为解决因实际输出约束突变而与期望轨迹发生冲突所引起的系统跟踪的安全性问题,针对一类具有未知控制方向、未建模动态及时滞的不确定非线性系统,提出一种自适应安全跟踪控制策略.基于一种新的预设有限时间性能函数(prescribed finite-time performance function, PFTPF)提出一种安全边界保护方法 (secure boundary protection method, SBPM). SBPM可以自动构建两条自适应调整的安全边界,确保系统同时满足安全边界约束和PFTPF规定的控制性能.在该方法中提出一种双向滤波平滑机制(bidirectional filtering smoothing mechanism,BFSM),能够显著抑制控制输入的大幅抖动.

关键词：非线性系统安全边界保护法双向滤波平滑机制输出约束安全跟踪控制

A novel high-Cr CoNi-based superalloy with superior high-temperature microstructural stability, oxidation resistance and mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1373-1381页

作者： Xiaorui Zhang Min zou Song Lu Longfei Li Xiaoli Zhuang Qiang Feng Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced MetalsUniversity of Science and Technology BeijingBeijing 100083China

A novel multicomponent high-Cr CoNi-based superalloy with superior comprehensive performance was prepared,and the evaluation of its high-temperature microstructural stability,oxidation resistance,and mechanical properties was conducted mainly using its cast polycrystalline *** results disclosed that the morphology of theγ′phase remained stable,and the coarsening rate was slow during the long-term aging at 900–1000℃.The activation energy forγ′precipitate coarsening of alloy 9CoNi-Cr was(402±51)kJ/mol,which is higher compared with those of CMSX-4 and some other Ni-based and Co-based ***,there was no indica-tion of the formation of topologically close-packed phases during this *** these factors demonstrated the superior microstructural stability of the *** mass gain of alloy 9CoNi-Cr was 0.6 mg/cm^(2) after oxidation at 1000℃ for 100 h,and the oxidation resistance was comparable to advanced Ni-based superalloys CMSX-4,which can be attributed to the formation of a continuous Al_(2)O_(3) protective ***,the compressive yield strength of this cast polycrystalline alloy at high temperatures is clearly higher than that of the conventional Ni-based cast superalloy and the compressive minimum creep rate at 950℃ is comparable to that of the conventional Ni-based cast superalloy,demonstrating the alloy’s good mechanical properties at high *** is partially because high Cr is bene-ficial in improving theγandγ′phase strengths of alloy 9CoNi-Cr.

关键词： CoNi-based superalloys microstructure coarsening oxidation mechanical properties

Research on virtual coupling technology in rail transit train collision protection

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Transportation Safety and Environment 2024年第1期6卷 40-46页

作者： Gaosong Li Jinbai zou Weijie Ma Meng Lan School of Railway Transportation Shanghai Institute of TechnologyShanghai 201418China Shanghai Metro First Operation Co. LtdShanghai 201418China

In the research on the new generation of intelligent rail transit system,the prevention of train collision accidents is still a *** coupling technology controls the running speed and interval distance of two or more trains cooperatively through Trainto-Train(T2T)direct communication *** aim is to form a coordinated logical system and jointly complete the train control and *** this paper,a virtual coupling train formation control method based on the model predictive control(MPC)framework is *** the establishment of the virtual coupling system,the construction of an MPC model and decoupling method,how to integrate virtual coupling technology into the rail transit train collision protection is *** safety and reliability of the system are calculated through fault tree and the method of constructing reliability *** research shows that if virtual coupling technology is used for train collision protection,the overall safety and reliability of the train control system is improved.

关键词： virtual coupling model predictive control collision protection

Effect of Down-regulation of MMP-2 by Quercetin on the Migration and Invasion of Uterine Fibroids Cells through the cAMP Signaling Pathway

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Chinese Journal of Biomedical Engineering 2024年第2期33卷 54-61页

作者： LIN Shu-ping zou Xiao-fen Longyan First Affiliated Hospital of Fujian Medical University

Objective: To investigate the effect of down-regulation of matrix metalloproteinase-2(MMP-2) by down-regulating the cyclic adenosine monophosphate(cAMP) signaling pathway on the migration and invasion of uterine fibroids ***: A total of 65 female SD rats were randomly divided into five groups after being adaptively fed for 7 d. Except for the blank group, the remaining four groups of rats were injected with 0.05 mg/(100 g·d) estradiol benzoate and 0.5 mg/(100g·d) progesterone into the muscle to establish a uterine fibroids rat model. After successful modeling, the blank group and model group were given 200 mg/(kg·d) physiological saline by gavage,the low-dose group was given 100 mg/(kg·d) mifepristone by gavage, the medium-dose group was given 200 mg/(kg·d) mifepristone by gavage, and the high-dose group was given 300 mg/(kg·d) mifepristone by gavage. After continuous gavage treatment for 21 d,serum and uterine tissues were collected from rats to observe and compare the expression levels of MMP-2 mRNA, TIMP-2 mRNA, estradiol(E2), cAMP signaling pathway related proteins, and the migration and invasive ability of uterine fibroids cells in the five groups of rats. Results: The expression levels of MMP-2 mRNA and E2in the high-dose group were lower than those in the low-dose group and the medium-dose group, and the expression level of TIMP-2 mRNA was higher than that in the low-dose group and the medium-dose group(P<0.05). The number of cell migration in a single visual field of rats in the high-dose group was lower than that in the low-dose group and the medium-dose group(P<0.05). The number of cell invasion in a single visual field of rats in the high-dose group was lower than that in the low-dose group and the medium-dose group(P<0.05). The mRNA expression levels of cAMP, PDE and PK in the high-dose group were higher than those in the low-dose group, and the mRNA expression levels of AC in the high-dose group were lower than those in the low-dose group(P<0.

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Two-stage Scheduling for Island CPHH IES Considering Plateau Climate

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1775-1786页

作者： Yuchen Pu Qi Li Yibin Qiu Xueli zou Weirong Chen School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China

In this paper,an island integrated energy system(IES)combining power,heat and hydrogen(CPHH)is built,and optimal power-heat-hydrogen scheduling is studied under actual plateau meteorological *** the comprehensive demands of residents,an IES including renewable energy sources(RESs),fuel cell,electrolyzer,electric boiler,thermal energy storage device and new energy vehicles is established and *** the first stage of operation,according to the prediction of RESs and demands,day-ahead optimization is carried out which aims to minimize operation cost,while electric vehicles(EVs)are considered as special demand response(DR)*** the second stage of operation,ultra-short-term prediction is implemented to provide prediction data for model predictive control(MPC),realizing real-time *** as a CPHH system,the fuel cell and electrolyzer collaborate to meet various needs of the plateau residential area with high *** addition,the method and IES structure proposed in this paper is compared with other options.

关键词： CPHH feul cell hydrogen island IES scheduling

Novel photoresponsive dinuclear nickel catalysts for ethylene(co)polymerization

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Science China Chemistry 2024年

作者： Chenlong nan Tong Pang Jiaxing Zhao Lijia Fan Chen zou Xin-Qi Hao Mao-Ping Song Jun-Fang Gong Changle Chen Hui Jiang College of Chemistry Pingyuan Laboratory Zhengzhou University CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China

Compared with the conventional strategies of electronic and/or steric perturbation, catalytic olefin polymerization modulated by light irradiation or metal-metal cooperativity effect is a fascinating challenge that attracts considerable attention in the academic community. In this context, we design a strategy that could employ both effects to influence the polymerization process. Some dinuclear salicylaldimine and α-imino-ketone nickel complexes bearing a stiff-stilbene bridge were prepared, which could transfer between(E)-isomers and(Z)-isomers under ultraviolet irradiation. This isomerization can tune the electronic, steric and metal-metal cooperativity effects of the nickel catalysts. In this way, the catalytic activity, as well as polymer microstructures including molecular weight and branching density can be modulated in ethylene polymerization and copolymerization *** strategy is generally applicable to other olefin polymerization catalytic systems and other types of transition metal mediated catalysis.

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Perpendicular-Cutdepth:Perpendicular Direction Depth Cutting Data Augmentation Method

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Computers, Materials & Continua 2024年第4期79卷 927-941页

作者： Le zou Linsong Hu Yifan Wang Zhize Wu Xiaofeng Wang Anhui Provincial Engineering Laboratory of Big Data Technology Application forUrban Infrastructure School ofArtificial Intelligence and Big DataHefei UniversityHefei230601China Institute of Applied Optimization School of Artificial Intelligence and Big DataHefei UniversityHefei230601China

Depth estimation is an important task in computer *** data at scale for monocular depth estimation is challenging,as this task requires simultaneously capturing RGB images and depth ***,data augmentation is crucial for this *** data augmentationmethods often employ pixel-wise transformations,whichmay inadvertently disrupt edge *** this paper,we propose a data augmentationmethod formonocular depth estimation,which we refer to as the Perpendicular-Cutdepth *** method involves cutting realworld depth maps along perpendicular directions and pasting them onto input images,thereby diversifying the data without compromising edge *** validate the effectiveness of the algorithm,we compared it with existing convolutional neural network(CNN)against the current mainstream data augmentation ***,to verify the algorithm’s applicability to Transformer networks,we designed an encoder-decoder network structure based on Transformer to assess the generalization of our proposed *** results demonstrate that,in the field of monocular depth estimation,our proposed method,Perpendicular-Cutdepth,outperforms traditional data *** the indoor dataset NYU,our method increases accuracy from0.900 to 0.907 and reduces the error rate from0.357 to *** the outdoor dataset KITTI,our method improves accuracy from 0.9638 to 0.9642 and decreases the error rate from 0.060 to 0.0598.

关键词： Perpendicular depth estimation data augmentation