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Effects of droplet size and spray volume parameters on droplet deposition of wheat herbicide application by using UAV

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International Journal of Agricultural and Biological Engineering 2021年第1期14卷 74-81页

作者： Changfeng Shan Guobin wang Haihong wang Yingjie Xie Huizheng wang shilong wang Shengde Chen Yubin Lan College of Agricultural Engineering and Food Science Shandong University of TechnologyShandong Provincial Engineering Technology Research Center for Agricultural Aviation Intelligent EquipmentZibo 255022ShandongChina Corteva Agroscience Technology(Shanghai)Co. LtdShanghai 201203China Zibo Agricultural and Rural Service Center Zibo 255022ShandongChina National Center for International Collaboration Research on Precision Agricultural Aviation Pesticides Spraying Technology(NPAAC) Ministry of Science and TechnologyCollege of Electronics EngineeringSouth China Agricultural UniversityGuangzhou 510642China Department of Biological and Agricultural Engineering Texas A&M UniversityCollege StationTX 77845USA

With the characteristic of flexible and precise,unmanned aerial vehicles(UAVs)for low volume applications are increasing substantially and quickly around the ***,little attention has been paid to the study of wheat herbicides with UAV,especially the research on the spray volume and droplet size of the herbicide sprayed by *** objectives of this study were to compare the droplet deposition from a typical commercial UAV under four different spray volumes of 7.5 L/hm2,15.0 L/hm2,22.5 L/hm2,and 30.0 L/hm2 and three different volume median diameter(VMD)of 150μm,200μm,and 300μm during winter wheat weeding *** software was used to analyze droplet deposition parameters including the percentage of spray coverage and the number of droplets in various sampling *** test results showed that the droplet deposition waseffected by each factor *** the spray volume was 7.5 L/hm2,the effect of VMD on the percentage of spray coverage was not ***,these variation rules were changed to smaller droplets with greater coverage when the spray volume higher than 15.0 L/*** all treatments,the number of droplets increased with decreasing VMD or increasing spray *** maximum percentage of spray coverage and the number of droplets that were achieved under the VMD of 150μm and the spray volume of 30.0 L/hm2 were 12.8%and 40.0 droplets/cm2,*** variation coefficients of the percentage of spray coverage and the number of droplets were 29.0%-73.3%and 20.2%-54.1%,*** most uniform deposition was achieved under the spray volume of 15.0 L/hm2and the VMD of 150μ*** results revealed the effect of droplet size and spray volume parameters on droplet deposition,which was useful for guiding farmers on how to use UAVs for weeding in winter wheat fields.

关键词： unmanned aerial vehicle spray volume droplet size droplet deposition

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Time-resolution enhanced multi-path OTD measurement using an adaptive filter based incoherent OFDR

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Chinese Optics Letters 2024年第1期22卷 153-158页

作者：王立晗任凌云王祥传潘时龙 National Key Laboratory of Microwave Photonics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

High accuracy and time resolution optical transfer delay(OTD)measurement is highly desired in many multi-path applications,such as optical true-time-delay-based array systems and distributed optical ***,the time resolution is usually limited by the frequency range of the probe signal in frequency-multiplexed OTD measurement ***,we proposed a time-resolution enhanced OTD measurement method based on incoherent optical frequency domain reflectometry(I-OFDR),where an adaptive filter is designed to suppress the spectral leakage from other paths to break the resolution limitation.A weighted least square(WLS)cost function is first established,and then an iteration approach is used to minimize the cost ***,the appropriate filter parameter is obtained according to the convergence *** a proof-of-concept experiment,the time-domain response of two optical links with a length difference of 900 ps is successfully estimated by applying a probe signal with a bandwidth of 400 *** time resolution is improved by 2.78times compared to the theoretical resolution limit of the inverse discrete Fourier transform(iDFT)*** addition,the OTD measurement error is below±0.8 *** proposed algorithm provides a novel way to improve the measurement resolution without applying a probe signal with a large bandwidth,avoiding measurement errors induced by the dispersion effect.

关键词： optical transfer delay measurement time resolution enhancement incoherent OFDR adaptive filtering

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Effects of high-energy-pulse-electron beam radiation on biomacromolecules

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Science China Chemistry 2008年第1期51卷 86-91页

作者： ZHU Hong XU JingZao LI ShiQiang SUN XiaoYu YAO SiDe wang shilong School of Life Science and Technology TongJi UniversityShanghai 200092China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

To study the molecular mechanism of high mutation frequency induced by high-energy-pulse-electron (HEPE) beam radiation, the effects of HEPE radiation on yeast cells, plasma membrane, plasmid DNA, and protein activity were investigated by means of cell counting, gel electrophoresis, AO/EB double fluorescent staining, etc. The results showed that the viability of yeast cells declined statistically with increase of absorbed doses. The half lethal dose (LD50) was 134 Gy. HEPE beam radiation had little influence on the function of plasma membrane and protein, while it could induce much DNA damage of single strand breaks (SSB) and double strand breaks (DSB) that were required for gene mutation. The G-value for DSB formation of HEPE beam radiation in aqueous solution was 5.7 times higher than that caused by 60Co gamma rays. HEPE can be a new effective method for induced mutation breeding and deserves further research in the future.

关键词： high-energy-pulse-electron beam biomacromolecule radiation damage

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Stochastic processes shape the functional and phylogenetic structure of bird assemblages at the mine area in southwest China

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Current Zoology 2024年第2期70卷 204-213页

作者： shilong Liu Tianlong Zhou Xiaocai Tan Wambura M.Mtemi Aiwu Jiang Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNo.100 East University RoadXixiangtang DistrictNanning 530004China

Understanding the mechanisms of community assembly is a key question in *** pollution may result in significant changes in bird community structure and diversity,with implications for ecosystem processes and ***,the relative importance of these pro-cesses in shaping the bird community at the polluted area is still not ***,we explored bird species richness,functional,and phylogenetic diversity,and the assembly processes of community at the mine region of southwest *** results showed that the 3 dimensions of diversity at the mine area were lower than that at the reference *** the community assembly,the result was O

关键词： clustering community assembly functional diversity mine area phylogenetic diversity stochastic process.

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Thermosphere joint observations by TM-1 constellations and Swarm-B during the April 2023 geomagnetic storm

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Earth and Planetary Physics 2024年第2期8卷 307-316页

作者： YongPing Li YueQiang Sun XianGuo Zhang JiangZhao Ai XiaoLiang Zheng Jia Li YuJie wang BiBo Guo Feng Yan shilong Wei XinChun Tang YuanYuan Cao National Space Science Center Chinese Academy of SciencesBeijing 100190China Beijing Key Laboratory of Space Environment Exploration Beijing 100190China Key Laboratory of Science and Technology on Space Environment Situational Awareness Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Shenzhen Aerospace Dongfanghong Satellite LtdShenzhen 518057China

The response of thermosphere density to geomagnetic storms is a complicated physical ***-satellite joint observations at the same altitude but different local times(LTs)are important for understanding this process;however,until now such studies have hardly been *** this report,we analyze in detail the thermosphere mass density response at 510 km during the April 23−24,2023 geomagnetic storm using data derived from the TM-1(TianMu-1)satellite constellation and Swarm-B *** observations show that there were significant LT differences in the hemispheric asymmetry of the thermosphere mass density during the geomagnetic *** observed by satellite TM02 at nearly 11.3 and 23.3 LTs were larger in the northern hemisphere than in the *** TM04 dayside density observations appear to be almost symmetrical with respect to the equator,though southern hemisphere densities on the nightside were ***-B data exhibit near-symmetry between the *** addition,the mass density ratio results show that TM04 nightside observations,TM02 data,and Swarm-B data all clearly show stronger effects in the southern hemisphere,except for TM04 on the dayside,which suggest hemispheric *** South-North density enhancement differences in TM02 and TM04 on dayside can reach 130%,and Swarm-B data even achieve 180%*** the observations of all three satellites,large-scale traveling atmospheric disturbances(TADs)first appear at high latitudes and propagate to low latitudes,thereby disturbing the atmosphere above the equator and even into the opposite ***00 model simulations were also performed on this geomagnetic *** are absent in the NRLMSISE00 *** satellite data suggest that NRLMSISE00 significantly underestimates the magnitude of the density response of the thermosphere during geomagnetic storms,especially at high latitudes in both ***,use of the density simulation of NRLM

关键词： TM-1 constellation Swarm-B joint observations geomagnetic storm Local Times

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Development of a supercritical and an ultra-supercritical circulating fluidized bed boiler

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Frontiers in Energy 2019年第1期13卷 114-119页

作者： Junfu LYU Hairui YANG Wen LING Li NIE Guangxi YUE Ruixin LI Ying CHEN shilong wang Tsinghua University Beijing 100084China Shenhua Group.Beijing 100031 China Dongfang Boiler Works Group Zigong 643001China

The supercritical circulating fluidized bed(CFB)boiler,which combines the advantages of CFB combustion with low cost emission control and supercritical steam cycle with high efficiency of coal energy,is believed to be the future of CFB combustion *** is also of greatest importance for low rank coal utilization in *** from the supercritical pulverized coal boiler that has been developed more than 50 years,the supercritical CFB boiler is still a new one which requires further *** any precedentor engineering reference,Chinese researchers have con ducted fundamental research,development,design of the supercritical CFB boilers *** design theory and key technology for supercritical CFB boiler were *** components and novel structures were *** first 600 MWe supercritical CFB boiler and its auxiliaries were successfully developed and demonstrated in Baima Power Plant,Shenhua Group as well as the simulator,control technology,installation technology,commissioning technology,system integration and operation *** with the 460 MWe supercritical CFB in Poland,developed in the same period and the only other supercritical one of commercial running in the word beside Baima,the 600 MWe one in Baima has a better ***,supercritical CFB boilers of 350 MWe have been developed and widely commercialized in *** this paper,the updated progress of 660 MWe ultra-supercritical CFB boilers under development is introduced.

关键词： supercritical circulating fluidized bed boiler development demonstration

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一种实际多约束环境下的云制造服务组合动态自适应重构方法

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机械工程学报 2023年第14期59卷 339-351页

作者：王彦凯王时龙杨波王四宝重庆大学机械传动国家重点实验室重庆400044 清华大学软件学院北京100084

以往云制造服务组合(Cloud manufacturing service composition,CMSC)优化是在制造服务少异常或约束的条件下进行的,这使得现有模型及方法无法适用于多种实际约束下的云制造服务组合优化,更无法在其执行过程出现服务异常时,对CMSC原执... 详细信息

以往云制造服务组合(Cloud manufacturing service composition,CMSC)优化是在制造服务少异常或约束的条件下进行的,这使得现有模型及方法无法适用于多种实际约束下的云制造服务组合优化,更无法在其执行过程出现服务异常时,对CMSC原执行路径进行自适应重构调整。为此,考虑云制造服务组合执行过程中不可忽视的原始CMSC执行路径强制时间约束、制造服务占用时间约束和制造服务强耦合约束,以CMSC的加工质量、成本、服务质量为优化目标,提出一种制造云服务出现异常时实际约束下的服务组合自适应重构调整模型(Cloud manufacturing service composition adaptive reconfiguration,CMSCAR)。为求解该模型,在详细分析所求问题的本质特征的基础上,集成多种优化策略,提出一种基于哈里斯鹰优化算法的服务组合动态重构算法(Service composition dynamic reconfiguration harris hawks optimization,SCDRHHO)。数值算例和应用案例表明,相比粒子群算法(Particle swarm optimization,PSO)、灰狼优化算法(Grey wolf optimizer,GWO)和蝠鲼觅食优化算法(Manta ray foraging optimization,MRFO)等对比算法,所提出的SCDRHHO能够在制造云服务异常出现时在多约束下对正在执行的服务组合进行高效地自适应重构调整,提高了云制造服务组合执行的鲁棒性。

关键词：云制造服务组合服务异常实际约束自适应重构哈里斯鹰优化算法

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Antitumor activity and pharmacokinetics of podophyllotoxin incorporated into solid lipid nanoparticles

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Science China Chemistry 2009年第8期52卷 1253-1257页

作者： XUE Meng ZHU RongRong QIN LiLi LI FaJie LIU ZhiXue SUN XiaoYu wang shilong School of Life Science and Technology Tongji UniversityShanghai 200092China

To evaluate the antitumor activity and pharmacokinetics of podophyllotoxin(PPT) incorporated into solid lipid nanoparticles(SLN),Kunming mice inoculated with flesh tumor were used as animal *** mice received a single daily intraperitoneal injection of PPT in 20% ethanol(5 mg/kg) and PPT-SLN(5 mg/kg in PPT) for 3 *** tumor volumes,body weight and clinical observations were recorded *** mice were sacrificed for 24 h after the last administration,and the tumor inhibition rate was calculated with the tumor *** the pharmacokinetics research,the mice were treated with intraperitoneal injection of PPT(10 mg/kg) and PPT-SLN(10 mg/kg in PPT).Blood samples were collected at different time to determine the PPT concentration in plasma by *** drug level-time curve was made and pharmacokinetic parameters were *** a result of drug administration,the tumor volume and weight of the mice injected with PPT-SLN were significantly restrained compared with mice treated with PPT or negative *** tumor inhibition rate of 58.13% showed a significant antitumor activity of *** the same time,the increased weight gain of the mice injected with PPT-SLN suggested a reduced toxicity of PPT in *** study displayed a higher blood concentration,a prolonged circulation time,and an increased bioavailability of PPT-SLN compared with those of *** results demonstrated that PPT-SLN could optimize pharmacokinetics,enhance antitumor activity and attenuate toxicity,so it has a promising prospect for the application in anti-tumor treatment.

关键词： podophyllotoxin solid lipid nanoparticles tumor

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Effects of biofertilizer and water-saving irrigation interactions on the leaf photosynthesis and plant growth of tomatoes

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 177-185页

作者： Danyan Chen Yuchun Ai Peizhe Li Yue Dong Hailing Li Changyi wang Xiaorui Jiang shilong Li Yan Shen Aijun Dai Yuanyuan Feng College of Horticulture Jinling Institute of TechnologyNanjing 210038China Co-Innovation Center for Sustainable Forestry in Southern China College of Forestry and GrasslandCollege of Soil and Water ConservationNanjing Forestry UniversityNanjing 210037China Institute of Agricultural Resources and Environment Jiangsu Academy of Agricultural SciencesNanjing 210014China Agriculture Exchange and Cooperation Center of Shandong Province Jinan 250100China Murdoch Applied Innovation Nanotechnology Research Group College of ScienceHealthEngineering and EducationMurdoch UniversityPerthWA 5150Australia

Irrigation and fertilizer interaction is an efficient cultivation management strategy for facility ***,the effects of irrigation and fertilizer management on tomato growth and its physiological factors remain *** this study,two irrigation patterns(W1,conventional irrigation;W2,water-saving irrigation)and four fertilizer application patterns(CF,chemical fertilizer;BOF,biological organic fertilizer;NPK,nutrient compound fertilizer;BOF+NPK)were selected to observe the effects of their interaction on cherry tomato plant growth,leaf photosynthesis and fruit quality through pot *** results showed that W2 treatments promoted plant height growth compared to W1 under the same fertilizer ***,irrigation and fertilizer management had significant effects on net photosynthetic rate,intercellular oxidation concentration,stomatal conductance and transpiration rate at the first sequence flowering and fruiting *** maximum tomato plant height(99.0 cm)was achieved under the irrigation and fertilizer pattern of BOF and W2,along with the highest fruit yield of 1.98 kg/plant,which was approximately 31.1%higher than the minimum yield under the combined CF and W2 *** W2 treatments,the application of either NPK or BOF increased the soluble sugar content of *** structural equation models showed that the soil alkali hydrolyzed nitrogen could directly significantly affect the yield and soluble *** findings suggest that optimization of irrigation-fertilizer interactions positively regulates tomato growth,providing an efficient model for tomato irrigation and fertilizer management and a reference for sustainable development of facility agriculture.

关键词： irrigation-fertilization interaction cherry tomato plant height leaf photosynthesis fruit yield and quality

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基于齿面位姿-几何误差模型的大规格滚齿机关键误差识别

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中国机械工程 2023年第5期34卷 533-542页

作者：李猛王时龙马驰夏长久重庆大学机械传动国家重点实验室重庆400044

为研究影响大规格滚齿机加工精度的关键几何误差,提出了一种基于齿面位姿-几何误差模型结合Sobol法的机床关键几何误差识别方法。首先,基于齐次坐标变换理论,建立了刀具位姿-几何误差模型,通过求解滚齿双参数包络方程,获得了加工齿面接... 详细信息

为研究影响大规格滚齿机加工精度的关键几何误差,提出了一种基于齿面位姿-几何误差模型结合Sobol法的机床关键几何误差识别方法。首先,基于齐次坐标变换理论,建立了刀具位姿-几何误差模型,通过求解滚齿双参数包络方程,获得了加工齿面接触迹点坐标值,建立了机床齿面位姿-几何误差模型;然后,考虑几何误差的随机性和互耦性,利用Sobol法对该模型进行敏感性分析,计算了几何误差的敏感度系数以识别出关键几何误差;最后,进行了关键几何误差虚拟仿真修正和对比验证。研究结果表明,所提方法能有效识别大规格滚齿机的关键误差项。

关键词：大规格滚齿机齿面位姿-几何误差 Sobol法敏感性分析

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