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A dynamic regulation of nitrogen on floret primordia development in wheat

The Crop Journal 2024年第1期12卷 271-280页

作者： Zhen Zhang yujing Li Yuxun Wu Xiaoyu zheng Xiaolei Guo Wan Sun Zhencai Sun Zhimin Wang Yinghua Zhang College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China College of Biological Sciences China Agricultural UniversityBeijing 100193China Engineering Technology Research Center for Agriculture in Low Plain Areas Cangzhou 061800HebeiChina

Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilization is largely unknown.A high temporal-resolution investigation of floret primordia number and morphology,dry matter,and N availability was conducted under three N fertilization levels:0(N0),120(N1)and 240(N2)kg ha^(−1).Interestingly,fertile florets at anthesis stage were determined by those floret primordia with meiotic ability at booting stage:meiotic ability was a threshold that predicted whether a floret primordium became fertile or abortive *** the developmental rate of the 4th floret primordium in the central spikelet was accelerated and then they acquired meiotic ability,the NFFs increased gradually as N application increased,but the increase range decreased under *** were no differences in spike N concentration among treatments,but leaf N concentration was increased in the N1 and N2 ***,dry matter accumulation and N content of the leaf and spike in the N1 and N2 treatments was increased as compared to ***,optimal N fertilization increased leaf N availability and transport of assimilates to spikes,and allowed more floret primordia to acquire meiotic ability and become fertile florets,finally increasing *** was no difference in leaf N concentration between N1 and N2 treatment,whereas soil N concentration at 0–60 cm soil layers was higher in N2 than in N1 treatment,implying that there was still some N fertilization that remained ***,improving the leaf’s ability to further use N fertilizer is vital for greater NFFs.

关键词： Fertile florets Floret primordia Grain number Meiotic ability Morphological development

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Optimization of Identifying Point Pollution Sources for the Convection-Diffusion-Reaction Equations

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Advances in Applied Mathematics and Mechanics 2021年第1期13卷 1-17页

作者： yujing Yuan Dong Liang College of Science Henan University of TechnologyZhengzhouHenan 450001China Department of Mathematics and Statistics York UniversityTorontoOntarioM3J 1P3Canada

In this paper,we consider the optimization problem of identifying the pollution sources of convection-diffusion-reaction equations in a groundwater *** optimization model is subject to a convection-diffusion-reaction equation with pumping point and pollution point *** develop a linked optimization and simulation approach combining with the Differential Evolution(DE)optimization algorithm to identify the pumping and injection rates from the data at the observation *** experiments are taken with injections of constant rates and timedependent variable rates at source *** problem with one pumping point and two pollution source points is also *** results show that the proposed method is *** developed optimized identification approach can be extended to high-dimensional and more complex problems.

关键词： Convection-diffusion-reaction equation optimization of identification pumping point pollution source point DE algorithm

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Protecting endemic seed plants on the Tibetan Plateau under future climate change: migration matters

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Journal of Plant Ecology 2019年第6期12卷 962-971页

作者： yujing Yan Zhiyao Tang Institute of Ecology College of Urban and Environmental SciencesKey Laboratory of Earth Surface Processes of Ministry of EducationPeking UniversityBeijing 100871China Center for Macroecology Evolution and ClimateNatural History Museum of DenmarkUniversity of CopenhagenCopenhagen 2100Denmark

Aims Climate change in the near future may become a major threat to high-altitude endemics by greatly altering their *** aims are to(i)assess the potential impacts of future climate change on the diversity and distribution of seed plants endemic to the Tibetan Plateau and(ii)evaluate the conservation effectiveness of the current National Nature Reserves(NNRs)in protecting the endemic plants in the face of climate *** We projected range shifts of 993 endemic species to the years 2050 and 2070 under two representative concentration pathway scenarios using an ensemble species distribution modeling framework and evaluated range loss,species-richness change and coverage of the current conservation network considering two dispersal *** Findings In a full-dispersal scenario,72–81%of the species would expand their distribution by 2070,but 6–20%of the species would experience>30%range *** species would shift to the *** projected species net richness would increase across the region on *** a no-dispersal scenario,15–59%of the species would lose>30%of their current habitat by *** species loss may occur in the southeastern and the eastern peripheral *** percent of species ranges are covered by the NNRs on average and may increase in the future if species disperse *** found a significant difference of species redistribution patterns between different dispersal scenarios and highlighted the importance of migration in this region.

关键词： biodiversity global change impact assessment nature reserves species conservation species distribution models

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The nature frequency identification of tunnel lining based on the microtremor method

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Underground Space 2016年第2期1卷 108-113页

作者： yujing Jiang Yang Gao Xuezhen Wu Graduate School of Engineering Nagasaki UniversityNagasaki 852-8521Japan Key Laboratory of Structural Health Monitoring and Control Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266510China

Many tunnels all over the world have been in service for several decades,which require effective inspection methods to assess their health ***,as a type of ambient vibration originating from natural or artificial oscillations without specific sources,has attracted more and more attentions in the recent study of the microtremor dynamic properties of concrete *** this study,the microtremors of the tunnel lining were simulated numerically based on the Distinct Element Method(DEM).The Power Spectra Density(PSD)of signals obtained from numerical simulations were calculated and the nature frequencies were identified using the peak-picking *** influences of the rock-concrete joint,the rock type and the concrete type on the nature frequencies were also *** results of a comprehensive numerical analysis show that the nature frequencies lower than 100 Hz can be *** the bonding condition becomes worse,the nature frequencies *** nature frequencies change proportionally with the normal stiffness of the rock-concrete *** the concrete grade decreases,the third mode of frequency also decreases gradually while the variation of the first two modes of frequencies can hardly be ***,the field microtremor measurements of tunnel lining were also carried out to verify the numerical results.

关键词： Tunnel lining Frequency Vibration intensity Microtremor measurement Numerical simulation

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In-situ construction of a Mg-modified interface to guide uniform lithium deposition for stable all-solid-state batteries

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Journal of Energy Chemistry 2021年第4期30卷 272-278页

作者： Tiefeng Liu Jiale zheng Hualiang Hu Ouwei Sheng Zhijin Ju Gongxun Lu yujing Liu Jianwei Nai Yao Wang Wenkui Zhang Xinyong Tao College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014ZhejiangChina

Uniform lithium(Li)deposition in all-solid-state Li metal batteries is greatly influenced by the anode/electrolyte ***,a Mg-modified interface was constructed via the simple in-situ electrochemical reduction of Mg^(2+)from Mg(TFSI)_(2) in polyethylene oxide(PEO)and a Li bis(trifluoromethane)sulfoni mide(Li TFSI)*** confirmed by cryogenic transmission electron microscopy,the anode/electrolyte interface exhibited hybrids consisting of crystalline Mg,Li_(2)O,and Li dots embedded in an amorphous polymer *** crystalline Mg dots guided the uniform Li nucleation and growth,inducing a smoother anode/electrolyte interface compared with the pristine *** 1 wt%Mg(TFSI)_(2) in the PEO-Li TFSI electrolyte,the Mg-modified electrolyte enabled the Li/Li symmetric cells with cycling performance of over 1700 and 1400 h at current densities of 0.1 and 0.2 m A cm^(-2),***,the full LFP/Li cells using the novel Mg-modified electrolyte delivered a cycling lifespan of over 450 cycles with negligible capacity loss.

关键词： Li metal PEO electrolyte Mg-modified interface Li dendrite Cryo-TEM

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Seru Scheduling Problems with Multiple Due-Windows Assignment and Learning Effect

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Journal of Systems Science and Systems Engineering 2022年第4期31卷 480-511页

作者： yujing Jiang Zhe Zhang Xiaoling Song Yong Yin School of Economics and Management Nanjing University of Science and TechnologyNanjing210094P.R.China Graduate School of Business Doshisha UniversityKarasuma-ImadegawaKamigyo-kuKyoto602-8580Japan

This paper deals with seru scheduling problems with multiple due windows assignment and DeJong’s learning *** time intervals are assigned to jobs with multiple due windows and learning effect is introduced to characterize the decrease of processing times with the accumulation of the working *** assume that the set of jobs assigned to each due window is independent,and no inclusion exists between due *** objective is to determine the optimal due window positions and sizes,the set of jobs assigned to each due window,and the optimal schedule in each seru to minimize a multidimensional function,which consists of the earliness and tardiness punishment cost,as well as the due window related starting time and size *** find that when the number of jobs and the due windows assigned to each seru are pre-specified in advance,the problem can be solved in polynomial ***,the impacts of the due-window allocation strategy and learning effect on the total cost are respectively discussed based on numerical examples and special *** results show that if each seru is assigned with the same number of due windows,the total cost can be reduced with the increasing ratio of the due-window number to the to-be-processed job ***,with an increasing learning effect,the total cost will be decreased.

关键词： Scheduling seru production system due windows learning effect

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Preliminary report on methane emissions from the Three Gorges Reservoir in the summer drainage period

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Journal of Environmental Sciences 2011年第12期23卷 2029-2033页

作者： Fei Lu Le Yang Xiaoke Wang Xiaonan Duan yujing Mu Wenzhi Song Feixiang zheng Junfeng Niu Lei Tong Hua zheng Yongjuan Zhou Jiangxiao Qiu Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Graduate University of Chinese Academy of Sciences Beijing 100049 China General Office of Chinese Academy of Sciences Beijing 100864 China Laboratory of Atmospheric Chemistry and Air Pollution Control Techniques Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Recently reported summertime methane （CH4） emissions （6.7 ± 13.3 mg CH4/（m2·hr）） from newly created marshes in the drawdown area of the Three Gorges Reservoir （TGR）, China have triggered broad concern in academic circles and among the public. The CH4 emissions from TGR water surfaces and drawdown areas were monitored from 3rd June to 16th October 2010 with floating and static chambers and gas chromatography. The average CH4 emission flux from permanently flooded areas in Zigui, Wushan and Yunyang Counties was （0.33 ± 0.09） mg CH4/（m2·hr）. In half of these hottest months of the year, the wilderness, cropland and deforested drawdown sites were aerobic and located above water level, and the CH4 emissions were very small, ranging from a sink at 0.12 mg CH4/（m2·hr） to a source at 0.08 mg CH4/（m2·hr） except for one mud-covered site after flood. Mean CH4 emission in flooded drawdown sites was 0.34 mg CH4/（m2·hr）. The emissions from the rice paddy sites in the drawdown area were averaged at （4.86 ± 2.31） mg CH4/（m2·hr）. Excepting the rice-paddy sites, these results show much lower emission levels than previously reported. Our results indicated considerable spatial and temporal variation in CH4 emissions from the TGR. Human activities and occasional events, such as flood, may also affect emission levels. Long-term CH4 measurements and modeling in a large region are necessary to accurately estimate greenhouse gas emissions from the TGR.

关键词： methane the Three Gorges Reservoir drawdown area summer drainage uncertainty flood

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Rh（Ⅰ）-Catalyzed Arylation of α-Diazo Phosphonates with Aryl Boronic Acids： Synthesis of Diarylmethylphosphonates

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Chinese Journal of Chemistry 2017年第5期35卷 621-627页

作者： yujing Zhou Yan Zhang Jianbo Wang Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry Peking University Beijing 100871 China The State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences Shanghai 200032 China

An efficient synthetic method for diarylmethylphosphonates is presented.A series of phosphonate derivatives with diverse functional groups can be accessed via a rhodium catalyzed cross-coupling reaction between a-diazo phosphonates and aryl boronic *** insertion of rhodium carbene intermediates is postulated to be the critical step in this transformation.

关键词： Rh(I)-catalysis metal carbene migratory insertion a-diazo phosphonates aryl boronic acids

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Multi-scale Cyclone Activity in the Changjiang River–Huaihe River Valleys during Spring and Its Relationship with Rainfall Anomalies

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Advances in Atmospheric Sciences 2017年第2期34卷 246-257页

作者： yujing QIN Chuhan LU Liping LI Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of lnformation Science and TechnologyNanjing 210044China

Based on the recognition framework of the outermost closed contours of cyclones, an automated identification algorithm capable of identifying the multi-scale cyclones that occur during spring in the Changjiang River-Huaihe River valleys （CHV） were developed. We studied the characteristics of the multi-scale cyclone activity that affects CHV and its relationship with rainfall during spring since 1979. The results indicated that the automated identification algorithm for cyclones proposed in this paper could intuitively identify multi-scale cyclones that affect CHV. The algorithm allows for effectively describing the shape and coverage area of the closed contours around the periphery of cyclones. We found that, compared to the meso- and sub-synoptic scale cyclone activities, the synoptic-scale cyclone activity showed more intimate correlation with the overall activity intensity of multi-scale CHV cyclones during spring. However, the frequency of occurrence of sub-synoptic scale cyclones was the highest, and their effect on changes in CHV cyclone activity could not be ignored. Based on the area of impact and the depth of the cyclones, the sub-synoptic scale, synoptic scale and comprehensive cyclone intensity indices were further defined, which showed a positive correlation with rainfall in CHV during spring. Additionally, the comprehensive cyclone intensity index was a good indicator of strong rainfall events.

关键词： cyclone activity multi-scale cyclone extreme precipitation CHV area

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Energy efficiency enhancement in heterogeneous networks:a joint resource allocation approach

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The Journal of China Universities of Posts and Telecommunications 2015年第4期22卷 74-80页

作者： Sun yujing Wang Yongbin Li Yi Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications

To support the drastic growth of wireless multimedia services and the requirements of ubiquitous access, numerous wireless infrastructures which consume enormous energy, such as macrocell, small cell, distributed antenna systems and wireless sensor networks, have been deployed. Under the background of environmental protection, improving the energy efficiency（EE） in wireless networks is becoming more and more important. In this paper, an EE enhancement scheme in heterogeneous networks（Het Nets） by using a joint resource allocation approach is proposed. The Het Nets consists of a mix of macrocell and small cells. Firstly, we model this strategic coexistence as a multi-agent system in which decentralized resource management inspired from Reinforcement Learning are devised. Secondly, a Q-learning based joint resource allocation algorithm is designed. Meanwhile, with the consideration of the time-varying channel characteristics, we take the long-term learning reward into account. At last, simulation results show that the proposed decentralized algorithm can approximate to centralized algorithm with low-complexity and obtain high spectral efficiency（SE） in the meantime.

关键词： heterogeneous networks energy efficiency reinforcement learning decentralized resource allocation joint resource allocation appr

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