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Characteristics and influencing factors of greenhouse gas emissions from reservoirs in the Yellow River Basin:A Meta-analysis

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Science China Earth Sciences 2024年第7期67卷 2210-2225页

作者： Shurui HUANG Peijia ZHANG wenxiu zheng Jiajia ZHANG Yang LI Yuanjian WANG Enhui JIANG Shaoda LIU Xinghui XIA State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 00875China Yellow River Institute of Hydraulic Research Yellow River Conservancy CommissionZhengzhou 450003China

Reservoir construction and operation profoundly alter the hydrological,hydrodynamic,and carbon and nitrogen cycling processes of ***,current research still lacks a systematic understanding of the characteristics of greenhouse gas(GHG)emissions from reservoirs in arid/semi-arid *** study integrates existing monitoring data to discuss the characteristics of GHG emissions from reservoirs in the Yellow River Basin and illustrate the controlling factors and underlying mechanism of these *** results indicate that while CO_(2) emission flux from reservoirs is lower than that from river channels,the emission fluxes of CH_(4) and N_(2)O are 1.9 times and 10 times those from rivers,respectively,indicating that the emission of GHG with stronger radiative effect is significantly enhanced in *** to the reservoirs in humid climates(e.g.,the Three Gorges Reservoir),reservoirs in the Yellow River Basin exhibit relatively lower emissions of CO_(2) and CH_4 due to lower organic matter concentrations,but significantly higher N_(2)O emissions due to higher nitrogen *** Carlo simulations for 237 reservoirs in the Yellow River Basin showed that total emission of the three GHGs is 3.05 Tg CO_(2)-eq yr^(-1),accounting for 0.39% of the total emission from global reservoirs and lower than the area percentage of the basin(0.53%).This study has important implications on revealing the GHG emission characteristics and control mechanisms of reservoirs in arid/semi-arid regions.

关键词： Yellow River Basin Reservoir Greenhouse gas Emission flux Water quality

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Optimization and experimental analysis of sweet potato ship-shaped transplanting trajectory using particle swarm algorithm

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INTERNATIONAL JOURNAL OF AGRICULTURAL AND BIOLOGICAL ENGINEERING 2024年第3期17卷 100-107页

作者： Liu, zhengduo Hua, Lin Lyu, Zhaoqin Hu, Jiaji zheng, wenxiu West Anhui Univ Coll Mech & Vehicle Engn Luan 237000 Anhui Peoples R China West Anhui Univ Tradit Chinese Med Inst Anhui Dabie Mt Luan 237012 Anhui Peoples R China Shandong Agr Univ Coll Mech & Elect Engn Tai An 271018 Shandong Peoples R China Anhui zhengyang Machinery Technol Co Ltd Luan 237012 Anhui Peoples R China

The mechanization of ship-shaped transplanting is currently an urgent problem that should be solved. The movement trajectory of the transplanting mechanism is the key technology to perform ship-shaped transplanting. In this study, a shipshaped transplanting trajectory was built and a mathematical model of a four-link transplanting mechanism was developed based on the requirements of the sweet potato transplanting agronomic technology. The particle swarm optimization algorithm was used, with the length of the four-bar mechanism and the installation angle of the fixed bar serving as the variables to optimize. The objective was to minimize the deviation of the ship-shaped transplanting trajectory, yielding an iterative optimization solution. The MATLAB simulation results showed that the penalty factors of different proportions in the adaptive particle swarm optimization algorithm affected the transplanting trajectory. The optimal penalty factor parameters are alpha=0.6, beta=0.4. They ensure that the transplanting trajectory fulfills the agronomic requirements, and limit the deviation in the return trajectory of the mechanism. The sizes of the optimized four-bar mechanism were 110, 312, 245, 160, 360, and, 160 mm. The determined installation angle was 100 degrees. The results of the field experiments demonstrated that the optimized four-bar transplanting mechanism can better fulfill the agronomic technical requirements of sweet potato ship-shaped transplanting. For a transplanting speed of 0.2 m/s, the average qualified rates of insertion depth, insertion length, and tail height were equal to 94.00%, 93.83%, and 91.67%. The results obtained in this study provide a theoretical basis and technical support for studying and developing sweet potato ship-shaped transplanting machinery.

关键词： sweet potato oblique insertion method mechanical arm particle swarm DESIGN SEPARATION SYSTEM DEVICE

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油-水-固三相接触线移动的温度影响机制

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中国科学：物理学、力学、天文学 2024年第2期54卷 62-71页

作者：郑文秀温伯尧白博峰空军工程大学防空反导学院西安710051 西安交通大学动力工程多相流国家重点实验室西安710049

温度会显著影响三相接触线的移动,从分子尺度获得接触线微观运动规律及温度影响机理,对深入研究纳米空间内的油水流动具有重要意义.本文构建了正癸烷-水-二氧化硅三相接触线的分子动力学模型,从接触线运动机制、分子取代频率及分子跳跃... 详细信息

温度会显著影响三相接触线的移动,从分子尺度获得接触线微观运动规律及温度影响机理,对深入研究纳米空间内的油水流动具有重要意义.本文构建了正癸烷-水-二氧化硅三相接触线的分子动力学模型,从接触线运动机制、分子取代频率及分子跳跃平均距离等角度,研究了不同三相润湿性时温度对三相接触线移动的影响.结果表明,油-水-固接触线在不同润湿性下呈现“翻转式”“塞状式”和“剪切式”几种机制,导致接触线运动速度呈现逐渐上升至平稳、逐渐下降至平稳和趋于0几种不同的规律,温度升高并未改变上述运动机制及规律.温度升高会引起分子能量增大、吸附密度降低,从而使分子在吸附位点之间的取代频率升高,且“塞状式”机制下分子取代频率的增加幅度明显大于“翻转式”,即在中等润湿性壁面时温度升高对三相接触线移动的促进作用大于亲水壁面.温度变化对分子跳跃平均距离的影响不大,温度升高导致分子取代频率的升高是加速接触线运动的主要原因.

关键词：三相接触线温度分子动力学

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一款冬暖夏凉电动自行车新能源智能型防护装置

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现代信息科技 2024年第3期8卷 182-185,190页

作者：蔡凤帅李丽欣郑文秀左凤华川山东华宇工学院山东德州253034

制作了一款冬暖夏凉电动自行车新能源智能型防护装置,其具有通过光伏发电装置储能、遮风挡阳、保护手部安全等特点。该装置充分利用电动自行车的车筐发电装置将太阳能转化为电能,利用温度传感器、热释电传感器、光照强度传感器和超声波... 详细信息

制作了一款冬暖夏凉电动自行车新能源智能型防护装置,其具有通过光伏发电装置储能、遮风挡阳、保护手部安全等特点。该装置充分利用电动自行车的车筐发电装置将太阳能转化为电能,利用温度传感器、热释电传感器、光照强度传感器和超声波传感器实现对温度、光照强度、头盔佩戴等数据的采集,通过STM32单片机进行相应的自动化控制,既解决了能源与环保问题,又提高了骑行者的安全性和舒适感。

关键词：新能源智能型防护装置光伏发电 STM32单片机能源与环保

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Design of obstacle avoidance controller for agricultural tractor based on ROS

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International Journal of Agricultural and Biological Engineering 2019年第6期12卷 58-65页

作者： zhengduo Liu Zhaoqin Lü wenxiu zheng Wanzhi Zhang Xiangxun Cheng College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018China Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment Tai’an 271018China

The obstacle avoidance controller is a key autonomous component which involves the control of tractor system dynamics,such as the yaw lateral dynamics,the longitudinal dynamics,and nonlinear constraints including the speed and steering angles limits during the path-tracking *** achieve the obstacle avoidance ability of control accuracy,an independent path re-planning controller is proposed based on ROS(Robot Operating System)nonlinear model prediction in this *** the design process,the obstacle avoidance function and an objective function are *** on these functions,the obstacle avoidance maneuvering performance is transformed into a nonlinear quadratic optimization problem with vehicle dynamic ***,the tractor dynamics maneuvering performance can be effectively adjusted through the proposed objective *** validate the proposed algorithm,a ROS based tractor dynamics model and the SLAM(Simultaneous Localization and Mapping)are established for numerical simulations under different *** maximum obstacle avoidance deviation in the simulation is 0.242 m at 10 m/s,and 0.416 m at 30 m/*** front-wheel rotation angle and lateral velocity are within the constraint range during the whole tracking *** numerical results show that the designed controller can achieve the tractor obstacle avoidance ability with good accuracy under different conditions.

关键词： ROS obstacle avoidance nonlinear model prediction agricultural tractor

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Trajectory tracking control of agricultural vehicles based on disturbance test

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International Journal of Agricultural and Biological Engineering 2020年第2期13卷 138-145页

作者： zhengduo Liu wenxiu zheng Neng Wang Zhaoqin Lyu Wanzhi Zhang College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTaian 271018ShandongChina Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment Taian 271018ShandongChina College of Physics and Electronic Science Hunan University of Science and TechnologyXiangtan 411201HunanChina

To improve the trajectory tracking robust stability of agricultural vehicles,a path tracking control method combined with the characteristics of agricultural vehicles and nonlinear model predictive control was *** the proposed method,the path tracking problem can be divided into two problems with speed and steering angle constraints:the trajectory planning problem,and the trajectory tracking optimization ***,the nonlinear kinematics model of the agricultural vehicle was discretized,then the derived model was inferred and regarded as the prediction function plant for the designed ***,the objective function characterizing the tracking performance was put forward based on system variables and control ***,the objective function optimization problem,based on the proposed prediction equation plant,can be regarded as the nonlinear constrained optimization ***’s more,to enhance the robust stability of the system,a real-time feedback and rolling adjustment strategy was adopted to achieve optimal *** validate the theoretical analysis before,the Matlab simulation was performed to investigate the path tracking *** simulation results show that the controller can realize effective trajectory tracking and possesses good robust ***,the corresponding experiments were *** the test vehicle tracked the reference track with a speed of 3 m/s,the maximum lateral deviation was 13.36 cm,and the maximum longitudinal deviation was 34.61 *** the added horizontal deviation disturbance Yr was less than 1.5 m,the controller could adjust the vehicle quickly to make the test car return to the reference track and continue to ***,to better highlight the controller proposed in this paper,a comparison experiment with a linear model predictive controller was *** to the conventional linear model predictive controller,the horizontal off-track distance reduced by 36.8%and

关键词： path tracking nonlinearity controller robustness

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Tremella polysaccharide mitigates high fat diet-induced anxiety-like behavior through the microbiota-gut-brain axis

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Food Science and Human Wellness 2024年

作者： Haicui Wu Shuyu Chen wenxiu Zhang Yuqing Lu Jiayi zheng Jinhui Chang Jiachi Chiou Research Institute for Future Food The Hong Kong Polytechnic University Shenzhen Key Lab for Food Biological Safety Control The Hong Kong Polytechnic University Shenzhen Research Institute Bo InnoHealth Biotechnology Company Limited Hong Kong Science Park Department of Food Science and Nutrition The Hong Kong Polytechnic University Department of Neurology The Second Affiliated Hospital of Guangzhou University of Chinese Medicine

High-fat diet (HFD) consumption induces gut microbiota dysbiosis and neuropsychiatric disorders， including anxiety. Previous research found that Tremella polysaccharide (TP) exhibited neuroprotective effects in vitro and in vivo. This study aimed to investigate the beneficial effects of TP on HFD-induced anxiety-like behaviors and elucidate the underlying mechanisms from the point view of the microbiota-gut-brain axis. Two groups of HFD-induced obese mice were orally gavaged with low dose (TPL， 40 mg/kg) and high dose (TPH， 400 mg/kg) of TP. A 12-week administration of TPH could significantly improve anxiety-like behaviors in HFD mice. In the hippocampus， microglia activation， the expression of blood-brain barrier (BBB) markers， and the levels of two neurotransmitters (serotonin and norepinephrine) were countered by TPH in mice consuming HFD. Furthermore， TPH improved the intestinal permeability and immune response of the enterocytes in HFD-fed mice. The gut microbiota dysbiosis induced by HFD was also rebalanced by TP treatments， especially in Proteobacteria and its lower taxa. The correlational analysis also suggested that shifts of some microbial genera were closely associated with body weight and the parameters of behavioral tests. Interestingly， fecal microbiota transplantation (FMT) results indicated that fecal microbiota from TPH-treated obese mice could prevent HFD-induced anxiety-like behaviors， suppressing microglia activation and intestinal permeability. In conclusion， the present study indicated that TP intake is a promising dietary intervention strategy to prevent HFD-induced anxiety via the microbiota-gut-brain axis.

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Fe-La二元氢氧化物对水中As(Ⅴ)和As(Ⅲ)的吸附行为与机制

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环境科学学报 2023年第4期43卷 276-288页

作者：潘燕芳张琳郭晨郑文秀樊帅兵刘颜红王玉龙河南大学地理与环境学院开封475004 河南大学河南省土壤重金属污染控制与修复工程研究中心开封475004 河南大学软件学院开封475004

采用共沉淀法制备了铁-镧二元氢氧化物(Fe-La)吸附剂,通过吸附动力学、pH的影响和吸附等温线等吸附批实验研究了其对水溶液中砷的去除行为,并通过扫描电子显微镜-X射线能谱分析(SEM-EDS)、傅里叶红外光谱分析(FTIR)、X射线衍射分析(XRD... 详细信息

采用共沉淀法制备了铁-镧二元氢氧化物(Fe-La)吸附剂,通过吸附动力学、pH的影响和吸附等温线等吸附批实验研究了其对水溶液中砷的去除行为,并通过扫描电子显微镜-X射线能谱分析(SEM-EDS)、傅里叶红外光谱分析(FTIR)、X射线衍射分析(XRD)等方法对铁-镧二元氢氧化物进行了表征,研究其对砷的去除机制.吸附批实验表明,Fe-La二元氢氧化物对As(Ⅴ)具有较强的去除能力,而对As(Ⅲ)的去除能力较弱.吸附动力学实验表明,Fe-La二元氢氧化物对As(Ⅴ)和As(Ⅲ)在前2 h内吸附速率较快,其去除过程均符合伪二级动力学模型.溶液的pH值会显著影响Fa-La二元氢氧化物对As(Ⅴ)和As(Ⅲ)的去除效率,其中,对As(Ⅴ)的吸附量在pH=3.0~4.0时升高,在pH=5.0~11.0时随pH升高而降低;对As(Ⅲ)的吸附量在pH=3.0~6.0时升高,在pH=6.0~10.0范围内保持不变,在pH=10.0~11.0时吸附量减少.Langmuir吸附等温线拟合结果表明,pH=4.0时Fe-La二元氢氧化物对As(Ⅴ)的最大吸附量为303.03 mg·g^(-1),pH=7.0时对As(Ⅲ)的最大吸附量为24.69 mg·g^(-1).共存阴离子对Fe-La二元氢氧化物去除As(Ⅴ)和As(Ⅲ)的影响大小顺序分别为SO_(4)^(2-)

关键词： Fe-La二元氢氧化物吸附 As(Ⅴ) As(Ⅲ) 砷酸镧共存阴离子

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聚合物表面活性剂在水泥基材料气泡调控中的应用现状

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高分子材料科学与工程 2024年第4期40卷 166-174页

作者：周红郑淑珍乔文秀徐守芳李因文马登学马建峰临沂大学化学化工学院山东临沂276000 临沂大学材料科学与工程学院功能高分子实验室山东临沂276000

水泥基材料中的气泡调控一直以来都是学科难题,通过多因素提高水泥基材料中气泡的稳定性和可控性,对提高水泥基材料的流变性能和耐久性能具有十分重要的意义。在众多影响因素中,气泡调控型聚合物表面活性剂在水泥基材料气泡调控中起到... 详细信息

水泥基材料中的气泡调控一直以来都是学科难题,通过多因素提高水泥基材料中气泡的稳定性和可控性,对提高水泥基材料的流变性能和耐久性能具有十分重要的意义。在众多影响因素中,气泡调控型聚合物表面活性剂在水泥基材料气泡调控中起到十分关键的作用。文中首先对新拌混凝土中气泡的形成和破灭过程进行了简单介绍,综述了影响气泡稳定性的主要因素,如引气型外加剂、减水剂及纳米颗粒等对气泡稳定性的影响,同时介绍了近年来引气型外加剂的合成研究进展。最后,讨论了水泥基材料中气泡对混凝土性能的重要意义。

关键词：聚合物表面活性剂气泡稳定性水泥基材料流变性耐久性

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基于FPGA的SM4算法高效实现方案

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通信学报 2024年第5期45卷 140-150页

作者：张宏科袁浩楠丁文秀闫峥李斌梁栋西安电子科技大学网络与信息安全学院陕西西安710126 中国电子科技集团公司第五十四研究所河北石家庄050299 西安电子科技大学空天地一体化综合业务网全国重点实验室陕西西安710071 西安电子科技大学杭州研究院浙江杭州311200

针对SM4算法的FPGA实现方案存在数据处理速度不够高和逻辑资源占用过高的问题,提出了基于现场可编程门阵列(FPGA)的高性能、低资源消耗的SM4算法实现方案。所提方案采用循环密钥扩展与32级流水线加解密相结合的架构,循环密钥扩展的方式... 详细信息

针对SM4算法的FPGA实现方案存在数据处理速度不够高和逻辑资源占用过高的问题,提出了基于现场可编程门阵列(FPGA)的高性能、低资源消耗的SM4算法实现方案。所提方案采用循环密钥扩展与32级流水线加解密相结合的架构,循环密钥扩展的方式降低了逻辑资源消耗,32级流水线加解密的方式提高了数据吞吐率。同时,所提方案采用代数式S盒并通过合并线性运算以及在不可约多项式的合并矩阵中筛选最优矩阵运算的方式进一步减少S盒变换的运算量,从而达到降低逻辑资源占用与提高工程数据吞吐率的目的。测试结果显示,该方案比现有最佳方案在数据吞吐率上提升了43%,且资源占用率降低了10%。

关键词： SM4算法 FPGA实现流水线架构代数式S盒

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