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Removal Effect of Precipitation on Atmospheric Particulate Matter (PM_(2.5) ) in Bengbu City

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Meteorological and Environmental Research 2024年第1期15卷 12-15,26页

作者： Lei TIAN Lei SHAN jingyang chen Bengbu Meteorological Bureau Bengbu 233000China

Based on the monitoring data of PM_(2.5) concentration in Bengbu Environmental Monitoring Station and precipitation observation data of Bengbu National Meteorological Observation Station from 2016 to 2019, the influence of precipitation on PM_(2.5) mass concentration in Bengbu City was analyzed. The results show that precipitation had a washing and removal effect on PM_(2.5) in the air, and the removal effect was related to precipitation level, precipitation intensity, precipitation duration and PM_(2.5) concentration. The removal effect of precipitation on PM_(2.5) increased with the increase of precipitation level, and the seasonal difference was obvious. Precipitation intensity was positively correlated with the removal effect of PM_(2.5) , but the average removal rate began to decline when precipitation intensity exceeded 10 mm. With the increase of precipitation intensity, the proportion of positive removal showed an overall upward trend, but there was a low-value area as precipitation intensity was 3-10 mm. Precipitation duration was also positively correlated with the removal effect of PM_(2.5) , and there was a low-value area when precipitation duration was 10-15 h. When PM_(2.5) concentration was low before the precipitation process began, the removal effect was not good, and the average removal rate was negative. As PM_(2.5) concentration was high before the precipitation process started, the removal effect was obvious.

关键词： Precipitation PM_(2.5) Removal efficiency Bengbu

Changing Characteristics of Comfort Index of Human Body in Bengbu City in the Past 40 Years under the Background of Climate Change

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Meteorological and Environmental Research 2024年第2期15卷 40-43页

作者： Lei SHAN Xian ZHANG Lei TIAN Ranran HE jingyang chen Bengbu Meteorological Bureau Bengbu 233000China Anhui University of Finance and Economics Bengbu 233000China

Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB was classified and discussed.The results show that from 1981 to 2020,annual average temperature tended to increase significantly.Annual average wind speed and relative humidity showed a decreasing trend before 2011 but an increasing trend after 2011.The duration of the four seasons in Bengbu City mainly rose in spring,reduced in winter,declined first and then increased in summer,and rose first and then decreased in autumn.As CIHB was at grades 1 and 9(the most uncomfortable),the three factors had different effects on them.For cold weather,the influence of relative humidity and wind speed on CIHB can not be ignored besides temperature.In hot weather,the influence of temperature was dominant,and the change of annual average temperature could well correspond to the change in the number of very hot days.In the context of climate warming,the number of cold days tended to decline generally,but it was larger in the years with fewer very cold days.Under the background of climate warming,there was no obvious change in the number of days of the overall comfort of human body.The number of hot days was closely related to the duration of summer,and the number of days of grade 8 rose significantly in the years with an increase in the duration of summer.

关键词： Climate change Human comfort Comfort index of human body(CIHB)

Parallelogram 3d-4f-5d heterometallic clusters based on trilacunary tungstoantimonates with excellent proton conductivity

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Chinese Chemical Letters 2024年第3期35卷 528-531页

作者： Haiying Wang Han Xu Chaolong chen Yingjie Zhu Yikang Zhang Dongdi Zhang jingyang Niu Henan Key Laboratory of Polyoxometalate Chemistry College of Chemistry and Molecular SciencesHenan UniversityKaifeng 475004China School of Pharmaceutical Science&Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical UniversityKunming 650500China Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surface and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Two 3d-4f-5d heterometallic cluster-containing polyoxometalates,formulated as Na_(22){(SbW_(9)O_(33))_(4)[La_(3)W_(6)MO_(18)(H_(2)O)_(8)(CH_(3)COO)_(4)]_(2)}·nH_(2)O(abbreviated as La_(6)M_(2),M=Co/Mn)were synthesized and structurally characterized.Single-crystal X-ray diffraction analyses reveal that the polyanions of La_(6)Co_(2)and La_(6)Mn_(2)consist of the uncommon 3d-4f-5d clusters{La_(6)W_(12)Co_(2)}and{La_(6)W_(12)Mn_(2)},which are encapsulated by four trilacunary Keggin tungstoantimonates to form the parallelogram-shaped title compounds.Additionally,the polyanions can be extended into a two-dimensional(2D)frame by the linkage of peripheral Na+ions.The inner space of the 2D layer was filled with water molecules and thus an H-bonded network was formed,which is expected to exhibit a fascinating proton conductivity.The study of water-assisted proton conduction demonstrated that La_(6)Co_(2)and La_(6)Mn_(2)were temperature-and humiditydependent proton conductors,respectively,and the proton conductivities could reach 1.3×10^(-2)and 2.3×10^(-2)S/cm at 65℃and 90%RH conditions.

关键词： Polyoxometalate Parallelogram Heterometallic 3d-4f-5d cluster Proton conductivity

An epidermal electrode based triboelectric walking energy harvester for wearable wireless sensing applications

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Science China(Technological Sciences) 2024年第3期67卷 949-957页

作者： CHANG ShiYuan LIU FuHai chen JinKai XIA LianBin ZHOU Hao JIANG jingyang DONG Kang ZHANG chenHao WU Yun chen Jin XUAN Weipeng SUN LingLing JIN Hao DONG ShuRong LUO JiKui Ministry of Education Key Laboratory of RF Circuits and Systems Hangzhou Dianzi UniversityHangzhou 310018China Special Equipment College Hangzhou Vocational&Technical CollegeHangzhou 310018China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 330027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China

Harvesting bio-kinetic energy using a triboelectric nanogenerator(TENG) is one of the promising routes to solve the sustainable energy supply problem for wearable electronics. However, additional materials, complex fabricating processes or specific mechanical structures are needed for existing TENGs to harvest bio-kinetic energy. Besides, they need to be tightly attached to the human body, which may result in detachment and malfunction under tense human motion. Herein, an intrinsic epidermal electrode-based TENG(E-TENG) is proposed to harvest human walking energy. The wearing shoes and ground are used as tribo-materials, and the human epidermis is used as the back electrode of the E-TENG. Compared with the traditional TENGs,the E-TENG does not need any additional tribo-materials and complex mechanical structures. Under optimal conditions, the voltage output of E-TENG can reach 914 V. E-TENG has been used as a self-powered warning sensor and pedometer sensor for demonstration. Furthermore, E-TENG based self-powered wireless sensor system has been developed using a newly designed micro energy electronic switch(MEES). Ambient ultraviolet intensity, temperature and humidity information can be monitored and then transmitted to mobile phone every 3.5 min, demonstrating great potential for widespread wearable applications.

关键词： triboelectric nanogenerator wearable wireless sensing self-powered

Intrinsic electrochemical activity modulation of MOF-derived C/N-NiCoMn-LDH/Ag electrode for low temperature hybrid supercapacitors

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Journal of Materials Science & Technology 2023年第19期150卷 145-158页

作者： Xiaohui Guan jingyang chen Enze Zhu Penggang Yin Liu Yang Xin Guan Guangsheng Wang School of Chemical Engineering Northeast Electric Power UniversityJilin 132012China School of Chemistry Beihang UniversityBeijing 100191China Department of Applied Physics Eindhoven University of Technology5600MB Eindhoventhe Netherlands

Layered double hydroxides(LDHs)are promising electrode candidates for supercapacitors.However,lim-itations like inferior cycling stability and unsatisfactory charge storage capability at low temperatures have exerted negative effects on their applications.Herein,a novel synthetic process has been elaborately designed and provided to have the composition and structure of the C/N-NiCoMn-LDH/Ag(C/N-CNMA)delicately regulated.Both the experimental and theoretical researches unveil that the incorporated manganese species and elemental silver could dramatically modulate the bandgap,crystallinity and surface electron structure of the LDH,leading to the remarkable improvement in its conductivity,exposed active sites and intrinsic electrochemical activity,and thus the OH^(*)and O^(*)adsorption free energy could be remarkably optimized,even at low temperatures.In addition,the low crystallinity C/N-CNMA is of great electrochemical compatibility with both the KOH aqueous electrolyte and the isobutyl alcohol(IPA)modulated organohydrogel electrolyte.By means of adjusting the solvation and hydrogen bonding in the electrolytes,the assembled hybrid supercapacitors deliver excellent energy density,power density and cycling stability in the temperature range of-30 to 25℃.Specifically,the gel electrolyte with IPA as the anti-freezing functional additive displays high flexibility and ionic conductivity at low temperatures.

关键词： Low crystallinity Intrinsic electrochemical activity modulation IPA modulated organohydrogel electrolyte Anti-freezing Low temperature hybrid supercapacitors

How could imperfect device properties influence the performances of spiking neural networks?

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Science China(Information Sciences) 2023年第8期66卷 233-242页

作者： jingyang chen Zhihao WANG Tong WANG Heming HUANG Zheyuan SHAO Zhe WANG Xin GUO State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and EngineeringHuazhong University of Science and Technology

Spiking neural networks(SNNs) provide an efficient way to apply artificial intelligence systems on edge devices. Memristive devices with tunable conductance states can be used to emulate the functions of biological neurons and synapses and to build SNNs. In this work, fully-connected SNNs based on various memristive devices are constructed, and a hardware-compatible spike-timing-dependent plasticity(STDP)learning rule is applied to train the SNNs. Strategies are designed to suppress the overfitting problem and improve the performance of the SNNs in the case of a small training set. However, the properties of memristive devices are never perfect. The effects of imperfect device properties, e.g., asymmetric weight update, insufficient number of conductance states, and low on/off ratio, on the performance of the SNNs are elaborated.

关键词： oxides memristive devices device properties spiking neural networks neuromorphic computing

Natural variation in maize gene ZmSBR1 confers seedling resistance to Fusarium verticillioides

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The Crop Journal 2024年第3期12卷 836-844页

作者： Yunxia Song Peipei Ma jingyang Gao Chaopei Dong Zhao Wang Yifan Luan Jiafa chen Doudou Sun Pei Jing Xuecai Zhang Weibin Song Zijian Zhou Jianyu Wu College of Agronomy Henan Agricultural UniversityZhengzhou 450002HenanChina College of Life Sciences Henan Agricultural UniversityZhengzhou 450002HenanChina Global Maize Program International Maize and Wheat Improvement Center(CIMMYT)Apdo 6-64106600 MexicoDFMexico National Maize Improvement Center Department of Plant Genetics and BreedingChina Agricultural UniversityBeijing 100193China

Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identified 40 and 20 QTNs,associated with seedling blight resistance.These methods identified 49 and 36 genes,respectively.Functional verification of candidate gene ZmSBR1 identified by both methods showed that the resistance of a mutant line to seedling blight decreased by 0.37 grade points after inoculation with F.verticillioides,compared with the WT.The length of the stem rot lesion caused by F.verticillioides increased by 86%in mutant seedlings,and the relative length of the adult plant stalk rot increased by 35%in mutant plants compared to the wild type after inoculation with Fusarium graminearum.Transcriptome analysis showed that expression of defense-related genes after inoculation was down-regulated in the mutant compared to the wild type,synthesis of secondary metabolites associated with resistance was reduced,and the immune response triggered by PAMP decreased,resulting in decreased resistance of mutant maize seedlings.Candidate gene association analysis showed that most maize inbred lines carried the susceptible haplotype.A functional PCR marker was developed.The results demonstrated that ZmSBR1 conferred resistance to multiple Fusarium diseases at the seedling and adult growth stages and had important application value in breeding.

关键词： Seedling blight Stalk rot Multiple disease resistance

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基于分形理论与幂律分布的微观天际线量化分析

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绿色建筑 2024年第1期16卷 69-74页

作者：袁敬洋陈萍华北水利水电大学河南郑州450046

城市天际线又称城市轮廓或全景,是城市景观的重要组成部分,利用分形理论与幂律分布方法可以为城市规划师或建筑师提供重要的理论支持。以郑州市为例,运用分形理论和幂律分布方法,对郑州市微观天际线的分形特征和相关建筑高度幂律分布进... 详细信息

城市天际线又称城市轮廓或全景,是城市景观的重要组成部分,利用分形理论与幂律分布方法可以为城市规划师或建筑师提供重要的理论支持。以郑州市为例,运用分形理论和幂律分布方法,对郑州市微观天际线的分形特征和相关建筑高度幂律分布进行研究。研究结果为深入理解微观天际线的形态特征和分布规律提供了有力的理论支持,在深化对城市天际线复杂性认识的同时,也为城市规划设计提供一定的参考。

关键词：微观天际线分形理论幂律分布城市规划建筑设计

Transition control of a tail-sitter unmanned aerial vehicle with L1 neural network adaptive control

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Chinese Journal of Aeronautics 2023年第7期36卷 460-475页

作者： jingyang ZHONG chen WANG Hang ZHANG School of Construction Machinery Chang’an UniversityXi’an 710061China

The main task of this work is to design a control system for a small tail-sitter Unmanned Aerial Vehicle(UAV)during the transition process.Although reasonable control performance can be obtained through a well-tuned single PID or cascade PID control architecture under nominal conditions,large or fast time-varying disturbances and a wide range of changes in the equilibrium point bring nonlinear characteristics to the transition control during the transition process,which leads to control precision degradation.Meanwhile,the PID controller’s tuning method relies on engineering experiences to a certain extent and the controller parameters need to be retuned under different working conditions,which limits the rapid deployment and preliminary validation.Based on the above issues,a novel control architecture of L1 neural network adaptive control associated with PID control is proposed to improve the compensation ability during the transition process and guarantee the security transition.The L1 neural network adaptive control is revised to solve the multi-input and multi-output problem of the tail-sitter UAV system in this study.Finally,the transition characteristics of the time setting difference between the desired transition speed and the desired transition pitch angle are analyzed.

关键词： L1 adaptive control Neural network Transition control Tail-sitter UAV Transition strategy