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A survey of composite robot for aviation intelligent manufacturing application

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High Technology Letters 2024年第1期30卷 85-98页

作者：陶永 xue jiao WEI Hongxing LIU Haitao GAO He wang Tianmiao School of Mechanical Engineering&Automation Beihang UniversityBeijing 100191P.R.China Research Institute of Aero Engine Beihang UniversityBeijing 100191P.R.China

With the rapid development of the aviation industry,the development of intelligent manufacturing equipment represented by composite robots has been paid close attention by the aviation *** on the analysis of the background and main structure function of composite robots,this paper focuses on the analysis of key technologies such as composite robot hardware design,visual sensing and planning system,integrated control of‘hands,feet,and eyes',multi-robot collaborative operation,and *** typical applications of composite robots in aviation intelligent manufacturing such as automatic drilling and connection of aircraft,aircraft surface spraying and finishing,parts handling,aircraft measurement,and inspection are *** development trends such as standardization of composite robots,integration of‘5G+cloud computing+AI',and fusion of intelligent sensors are proposed.

关键词： aviation manufacturing composite robot key technology development trend safety

Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation

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食品科学 2025年第1期46卷 131-141页

作者： SUN Yupeng CHEN Ying SHANG Qingwen GUO Yanyin ZHANG Yuxiao wang Yunqiao xue Qingyue College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255049China Zichuan District Agricultural and Rural Affairs Service Center Zibo 255049China

To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before *** appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of *** results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli ***,during the growth stage,total sugar accumulation was higher in the 5-ARG *** addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest *** conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of ***,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments.

关键词： arginine broccoli preharvest spraying nutrient accumulation storage quality postharvest senescence

从二元社会结构视角看地方农业产业转型升级——以陕西省猕猴桃产业为例

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三峡大学学报（人文社会科学版） 2025年第1期47卷 47-56页

作者：张继焦薛晓宏中国社会科学院大学社会与民族学院北京102488 中国社会科学院民族学与人类学研究所北京100081 中国社会科学院大学马克思主义学院北京102488

近年来,乡村产业振兴备受重视,许多地方都在致力于推动当地特色农业产业转型与升级,希望从区域走向全国乃至世界。但是现实中却发现很多地区特色农业产业的转型与升级面临着许多制约因素,那如何才能推动区域特色农业产业实现转型与升级... 详细信息

近年来,乡村产业振兴备受重视,许多地方都在致力于推动当地特色农业产业转型与升级,希望从区域走向全国乃至世界。但是现实中却发现很多地区特色农业产业的转型与升级面临着许多制约因素,那如何才能推动区域特色农业产业实现转型与升级,将区域特色农业产业推向全国呢?从二元社会结构视角,采用“伞式社会”和“蜂窝式社会”这一对概念,对陕西省猕猴桃产业发展历程进行阶段上的划分,详细分析了不同阶段官方“伞式社会”和民间“蜂窝式社会”力量的作用。通过不同阶段两种力量结构和功能的动态演变过程的分析,可以看到在每一阶段,找到官方“伞式社会”和民间“蜂窝式社会”二者发挥作用的结合点非常重要,双方都是可以发挥强大作用的主体,但是任何一方的单打独斗都无法在如今完成本区域农业产业的转型和升级,只有二者“高程度、高默契”的协同才能完成一个区域农业产业从传统向现代的转变,实现产业的转型与升级,从而实现从“区域到全国性”的跨越。

关键词：二元社会结构 “伞式社会” “蜂窝式社会” 陕西省猕猴桃产业

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基于北方寒地冻土的螺旋式挖坑机设计与试验

农机化研究 2025年第1期47卷 157-164,172页

作者：尹大庆王雪苏林峰东北农业大学工程学院哈尔滨150030

针对目前市场上缺少适宜冻土环境作业挖坑机械的问题,以适用于北方寒地的螺旋式挖坑机为研究对象,通过测量哈尔滨的冻土参数并与硬质土壤进行对比,获得工作对象土壤参数。结合移栽白桦树苗所需穴坑尺寸,对挖坑机工作部件进行参数设计。... 详细信息

针对目前市场上缺少适宜冻土环境作业挖坑机械的问题,以适用于北方寒地的螺旋式挖坑机为研究对象,通过测量哈尔滨的冻土参数并与硬质土壤进行对比,获得工作对象土壤参数。结合移栽白桦树苗所需穴坑尺寸,对挖坑机工作部件进行参数设计。根据运动学分析确定了升运土壤的临界转速,对挖坑机的工作参数进行分析,并得到了装置所需的功率。为便于开展试验验证,运用相似理论对试验装置和作业穴坑进行了等比例缩放,试验用钻头长度为400 mm,叶片长度为200 mm,钻尖半径为100 mm,转速大于155 r/min,动力源额定功率为4 kW。试验结果表明:当刀片组合方式为平刀-锯齿刀时,可以获得最短的挖坑时间。研究结果可为北方寒地秋冬季节冻土条件下,树苗移栽时螺旋式挖坑机的设计提供参考。

关键词：挖坑机螺旋式冻土钻头

Valuating service loss of snow cover in Irtysh River Basin

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Advances in Climate Change Research 2019年第2期10卷 109-114页

作者： YANG Yang WU xue-jiao LIU Shi-Wei XIAO Cun-De wang Xiaoming State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Etivironment and Resources Chinese Academ y o f Sciences Lanzhou 730000 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Earth Surface Processes and Resources Ecology Beijing Normal University Beijing 100875 China

Snow cover provides essential resources and services for human well-being and socioeconomic development in arid areas. With the change in snow cover resulting from climate change that causes concerns about its consequences, there is a pressing need to analyze and understand its impact on the benefits that people has been enjoying from snow cover. These can be derived from the variation in economic value of snow services, that are demanded to meet socioeconomic activities. Based on the average decline mass of snow cover from 1979 to 2016 in Irtysh River Basin, we use the approach by applying economic evaluation to estimate the annual value loss of snow services. Considering the decreasing trend of snow cover mass at rates of 10.2 Mt per year (p < 0.05) or 0.3% per year, the annual service loss in Irtysh River Basin is currently worth up to CN 196 million. Within it, the service loss of climate regulation contributes the most, or about CN 84.7 million. The loss of freshwater service contributes only about 19%, implying that there would be a significant underestimation of service loss if only water supply would be considered. This may cause biased decision-making when we are facing the challenges of declining services as a result of climate change, impacting on the balancing of socioeconomic development and environment conservation for the sustainability over a long term.

关键词： Cryosphere science Climate change Snow cover Cryosphere service Service value Irtysh river basin

Rational design of vitamin C/defective carbon van der Waals heterostructure for enhanced activity,durability and storage stability toward oxygen reduction reaction

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Journal of Energy Chemistry 2024年第1期88卷 103-111,I0003页

作者： Ruiqi Cheng Kaiqi Li Huanxin Li Tianshuo Zhao Yibo wang Qingyue xue jiao Zhang Chaopeng Fu Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Christopher Ingold Laboratory Department of ChemistryUniversity College LondonLondon WC1H 0AJUK Department of Chemistry Physical&Theoretical Chemistry LaboratoryUniversity of OxfordSouth Parks RoadOxford OX13QZUK

Metal-free defective carbon materials with abundant active sites have been widely studied as low-cost and efficient oxygen reduction reaction(ORR)electrocatalysts in metal-air ***,the active sites in defective carbon are easily subjected to serious oxidation or hydroxylation during ORR or storage,leading to rapid degradation of ***,we design a van der Waals heterostructure comprised of vitamin C(VC)and defective carbon(DC)to not only boost the activity but also enhance the durability and storage stability of the DC-VC *** formation of VC van der Waals between DC and VC is demonstrated to be an effective strategy to protect the defect active sites from oxidation and hydroxylation degradation,thus significantly enhancing the electrochemical durability and storage anti-aging ***,the DC-VC van der Waals can reduce the reaction energy barrier to facilitate the *** findings are also confirmed by operando Fourier transform infrared spectroscopy and density functional theory *** is necessary to mention that the preparation of this DC-VC electrocatalyst can be scaled up,and the ORR performance of the largely produced electrocatalyst is demonstrated to be very ***,the DC-VC-based aluminum-air batteries display very competitive power density with good performance maintenance.

关键词： Van der Waals heterostructure Oxygen reduction reaction Stability Scalable production Aluminum-air battery

Mechanism Studies on the Degradation of Hexachlorocyclopentadiene in the Atmosphere

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Chinese Journal of Structural Chemistry 2020年第11期39卷 1925-1932页

作者： YANG jiao-xue LV Guo-Chun wang Yan wang Ze-Hua SUN Xiao-Min LI Zhi-Qiang Environment Research Institute Shandong UniversityQingdao 266237China Center for Optics Research and Engineering(CORE) Shandong UniversityQingdao 266237China

Hexachlorocyclopentadiene(HCCP) is one of the chlorinated and highly reactive pollutants, which can be released into the atmosphere and undergo chemical transformations. In this paper, the initiated reaction mechanisms of HCCP with typical atmospheric oxidants(·NO3, ·HO2, ·OH, and O3) were theoretically investigated. The results mean that all initiated reactions are exothermic, and the energy barriers do not exceed 16 kcal×mol-1. The rate constants of HCCP reaction triggered by ·NO3, ·HO2, ·OH, and O3 are 2.49 × 10-12, 2.44 × 10-22, 2.46 × 10-13 and 1.33 × 10-20 cm3×molecule-1×s-1 at 298 K, respectively. It can be concluded that the reaction of ·NO3 and ·OH with HCCP more likely occurs according to the rate constants. Then the subsequent reactions of the ·NO3/·OH-initiated intermediates with O2 and NO were calculated, resulting in that the cyclopentadiene is ruptured completely. And the results show that the Criegee intermediates created in the ozonization reactions of HCCP can react with O2, NO2 and SO2. This study gives more insight into the chemical transformation mechanisms of HCCP in the atmosphere.

关键词： hexachlorocyclopentadiene theoretical calculations mechanism rate constant

A pseudoclassical theory for the wavepacket dynamics of the kicked rotor model

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 34-43页

作者： Zhixing Zou jiao wang Department of Physics and Key Laboratory of Low Dimensional Condensed Matter Physics(Department of Education of Fujian Province) Xiamen UniversityXiamen 361005China Lanzhou Center for Theoretical Physics Lanzhou UniversityLanzhou 730000China

In this study, we propose a generalized pseudoclassical theory for the kicked rotor model in an attempt to discern the footprints of the classical dynamics in the deep quantum regime. Compared with the previous pseudoclassical theory that applies only in the neighborhoods of the lowest two quantum resonances, the proposed theory is applicable in the neighborhoods of all quantum resonances in principle by considering the quantum effect of the free rotation at a quantum resonance. In particular, it is confirmed by simulations that the quantum wavepacket dynamics can be successfully forecasted based on the generalized pseudoclassical dynamics, offering an intriguing example where it is feasible to bridge the dynamics in the deep quantum regime to the classical dynamics. The application of the generalized pseudoclassical theory to the PT-symmetric kicked rotor is also discussed.

关键词： quantum-classical correspondence kicked rotor model pseudoclassical theory wavepacket dynamics

Superballistic wavepacket spreading in double kicked rotor

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Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 9-15页

作者： Ping Fang jiao wang Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen University

We investigate possible ways in which a quantum wavepacket spreads. We show that in a general class of double kicked rotor system, a wavepacket may undergo superballistic spreading; i.e., its variance increases as the cubic of time. The conditions for the observed superballistic spreading and two related characteristic time scales are studied. Our results suggest that the symmetry of the studied model and whether it is a Kolmogorov-Arnold-Moser system are crucial to its wavepacket spreading behavior. Our study also sheds new light on the exponential wavepacket spreading phenomenon previously observed in the double kicked rotor system.

关键词： quantum chaos quantum transport matter waves semiclassical methods