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Boundedness of Formation Configuration for Nonlinear Three-body Dynamics

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空间科学学报 2011年第2期31卷 214-222页

作者： LI peng song Yongduan Center for Intelligent Systems and Renewable Energy Beijing Jiaotong University Beijing 100044)

The configuration boundedness of the three-body model dynamics is studied for Sun-Earth formation flying *** three-body formation flying model is built up with considering the lunar gravitational acceleration and solar radiation *** traditional linearized dynamics based method has relatively lower accuracy,a modified nonlinear formation configuration analysis method is proposed in this *** studies are carried out from three aspects,i.e.,natural formation configuration with arbitrary departure time,initialization time and formation configuration boundedness,and specific initialization time for bounded formation *** demonstrate the differences between the two schemes, and indicate that the nonlinear dynamic method reduces the error caused by the model linearization and disturbance approximation,and thus provides higher accuracy for boundedness analysis,which is of value to initial parameters selection for natural three-body formation flying.

关键词： Formation flying Three-body Model Nonlinear dynamics Configuration boundedness

Graphene-anchored sodium single atoms:A highly active and stable catalyst for transesterification reaction

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Nano Research 2024年第6期17卷 4979-4985页

作者： song-song peng Yao Nian Xing-Ru song Xiang-Bin Shao Chen Gu Zhi-Wei Xing Shi-Chao Qi peng Tan You Han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Solid strong base catalysts have received considerable attention in various organic reactions due to their facile separation,neglectable corrosion,and environmental *** great progress has been made in the preparation of solid strong base catalysts,it is still challenging to avoid basic sites aggregation on support and active sites loss in reaction ***,we report a tandem redox strategy to prepare Na single atoms on graphene,producing a new kind of solid strong base catalyst(Na1/G).The base precursor NaNO_(3)was first reduced to Na2O by graphene(400℃)and successively to single atoms Na anchored on the graphene vacancies(800℃).Owing to the atomically dispersed of basicity,the resultant catalyst presents high activity toward the transesterification of methanol and ethylene carbonate to synthesize dimethyl carbonate(turnover frequency(TOF)value:125.7 h^(−1)),which is much better than the conventional counterpart Na2O/G and various reported solid strong bases(TOF:1.0-90.1 h^(−1)).Furthermore,thanks to the basicity anchored on graphene,the Na1/G catalyst shows excellent durability during *** work may provide a new direction for the development of solid strong base catalysts.

关键词： solid strong base catalyst basic sites redox graphene single Na atoms

Chromosomal Location of the Genes Associated with Photosynthesis of Lophopyrum elongatum (Host) A.Lve in Chinese Spring Background

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Agricultural Sciences in China 2006年第8期5卷 579-586页

作者： peng Yuan-ying peng Zheng-song song Hui-xing XU Jia-shao College of Life Science China West Normal University Nanchong 637002 P.R.China College of Life Science Qufu Normal University Qufu 273165 P.R.China College English Department Qufu Normal University Qufu 273165 P.R.China

Researches on the relationship between photosynthesis and wheat yield have equally attracted the attention of both domestic and overseas scholars. No report has existed so far on the study of the effects of exogenous chromosomes on photosynthesis using the substitution series as materials. In this research, Triticum aestivum cv. Chinese Spring-Lophopyrum elongatum （Host） *** disomic substitution series were used as materials and flag leaves as the measuring position. And the CI-310 Portable Photosynthesis System made by CID Co. in USA was used to measure the net rate of photosynthesis of flag leaves in different developing stages and also to correlate photosynthesis with yield. Results showed that, out of the whole developing stages, at the anthesis stage the line of DS2Ee （2A） had the highest photosynthetic rate, therefore it could be used in improving process of the character of kernel number. The flag leaves of DS4Ee （4A, 4B, 4D） lines demonstrated certain high net photosynthetic rate from heading to grain filling stage, so it is valuable in the researh of promoting the yield index like 1 000-grain weight through improvement of the photosynthetic rate at grain filling stage.

关键词： wheat Lophopyrum elongatum substitution photosynthetic rate gene location

Influence of coarse tailings on flocculation settlement

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1065-1074页

作者： Shi Wang Xue-peng song Xiao-jun Wang Qiu-song Chen Jian-chun Qin Yu-xian Ke School of Resources and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China School of Resources and Safety Engineering Central South UniversityChangsha 410083China Department of Personnel Guangxi University of Science and TechnologyLiuzhou 545006China

The composition of tailings particles in mines plays a key role in the flocculation settlement of *** study the influence of coarse particle tailings(CPTs)on the flocculation settlement of tailings slurries(TSs),static flocculent settling tests,scanning electron microscopy observations,and laser particle size analyses were conducted using the tailings obtained from a copper *** results demonstrate that(i)in the accelerated and free settling process,CPTs did not directly settle at the bottom of graduated cylinders;instead,they were netted by the flocculent structures(FSs)and settled together more *** CPTs accelerate the rapid settlement of TSs;the acceleration effect is more obvious when the CPTs content is greater than 50 wt%.(ii)The most appropriate flocculant unit consumption(FUC)is 20 g·t-1,and no substantial increase is observed in the flocculant settling velocity with an increase in the flocculant because the effective FSs did not substantially change and thus did not lead to a notable increase in the settling velocity of the solid–liquid interface(SLI).(iii)In the effective settling space of the thickening facility,free water quickly flowed from the pores of FSs,which is reflected in the period from 0 to 1 min.

关键词： tailings slurry particle size distribution flocculent structures flocculating sedimentation solid–liquid interface

The Cysteine Pairs in CLV2 are Not Necessary for Sensing the CLV3 Peptide in Shoot and Root Meristems

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Journal of Integrative Plant Biology 2010年第9期52卷 774-781页

作者： Xiufen song peng Guo Chen Li Chun-Ming Liu Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Receptor-like proteins （RLPs） are involved in both plant defense and developmental processes. Previous genetic and biochemical studies show that the leucine-rich repeat （LRR） receptor-like protein CLAVATA2 （CLV2） functions together with CLAVATA1 （CLV1） and CORYNE （CRN） in Arabidopsis to limit the stem cell number in shoot apical meristem, while in root it acts with CRN to trigger a premature differentiation of the stem cells after sensing the exogenously applied peptides of CLV3p, CLE19p or CLE40p. It has been proposed that disulfide bonds might be formed through two cysteine pairs in the extracellular LRR domains of CLV1 and CLV2 to stabilize the receptor complex. Here we tested the hypothesis by replacing these cysteines with alanines and showed that depletions of one or both of the cysteine pairs do not hamper the function of CLV2 in SAM maintenance. In vitro peptide assay also showed that removal of the cysteine pairs did not affect the perception of CLV3 peptides in roots. These observations allow us to conclude that the formation of disulfide bonds is not needed for the function of CLV2.

关键词： Proteins Protein products Roots Stems Shoots Cells Rooting Senses Peptides Cysteine

Improving global land cover characterization through data fusion

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Geo-Spatial Information Science 2017年第2期20卷 141-150页

作者： Xiao-peng song Chengquan Huang John R.Townshend Department of Geographical Sciences University of MarylandCollege ParkMDUSA

Global-scale land cover characterization has advanced from a spatial resolution of 1×1°in the mid-1990s to 30×30 m resolution to ***,some mapping challenges exist persistently regardless of the increasing spatial *** fusion has been proved as an effective way of improving land cover *** we applied a machine learning-based data integration approach for improving global-scale forest cover *** approach employed six coarse-resolution(250-1000 m)global land cover maps as input and various regional,higher-resolution land cover data-sets as reference to build regression tree models per *** average error of 10-fold cross validation of the regression tree models varied between 7.70 and 15.68% forest cover and the r2 varied between 0.76 and 0.94,indicating the robustness of the trained *** a result of data fusion,the synthesized global forest cover map was more accurate than any input global *** also showed that other major vegetative land cover types such as cropland,woodland,grassland,and wetland all exhibit similar magnitude of discrepancies as forest among existing land cover *** developed method,because of its type-and scale-invariant feature,can be implemented for other land cover types for improving their global *** ensemble approach can also be internalized for improving data quality when generating a global land cover product,where multiple versions can be produced and subsequently integrated.

关键词： Satellite remote sensing land cover data fusion regression tree global

Synthesis of Ba-doped porous LaFeO_(3) microspheres with perovskite structure for rapid detection of ethanol gas

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Rare Metals 2021年第6期40卷 1651-1661页

作者： Pei Hao Guang-Min Qu peng song Zhong-Xi Yang Qi Wang School of Material Science and Engineering University of JinanJinan 250022China Shandong Academy of Pharmaceutical Sciences Jinan 250101China

In this work,porous La_(1-x)Ba_(x)FeO_(3)(x=0.01,0.02,0.03,0.04 and 0.05) microspheres of the orthorhombic perovskite phase were prepared by an environment-friendly one-step hydrothermal method with a series of characterization of the six sensing *** results show that their grain size is between 21.2 and 23.2 nm,and the grain growth is inhibited with the increase in Ba-doping *** samples are all spherical with a diameter of about 10 μm,and the surface is very *** the gas sensing study of the samples,the results show that the La_(1-x)Ba_(x)FeO_(3) sensor exhibits a fairly high response to the ethanol *** particular,the La_(1-x)Ba_(x)FeO_(3) microspheres with a Ba-doping concentration of 2 mol% showed not only a significant improvement in sensitivity but also a rather rapid response recovery time compared to the undoped samples,demonstrating the superiority as an ethanol sensing *** importantly,the optimum operating temperature of La0.98Ba0.02FeO_(3) is only 200℃,while that of the pure LaFeO_(3) is 260℃.The Ba-doped porous microspheres prepared are a high-performance sensing material capable of rapid and accurate detection of ethanol.

关键词： Perovskite LaFeO_(3)microspheres Ba-doped Ethanol Gas sensors

Influence of Virtual Synchronous Generators on Low Frequency Oscillations

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1029-1038页

作者： Hui Liu Dawei Sun Feng Zhao Yunfeng Tian peng song Xuekun Cheng State Grid Wind-Photovoltaic-Energy Storage Hybrid Power Generation Technology Laboratory and State Grid Jibei Electric Power Research Institute(North China Electric Power Research Insititute Co.Ltd) Beijing 100045China State Grid Xinyuan Zhangjiakou Wind PhotovoltaicStorage and Transmission Pilot Power Station Co.LtdZhangjiakou 075000China

By simulating the operating dynamics of synchronous generators(SGs),the use of virtual synchronous gen-rators(VSGs)can help overcome inverter-based generators'shortcomings of low inertia and minimal damping for gridforming ***'stability are very important for their solar and wind electricity ***,the related research primarily focuses on VSGs and their applications for *** has been little research to explore how VSGs effect low frequency oscillations in power transmission *** paper describes a small-signal model of a VSGSG interconnected system,which is suitable for studying low frequency oscillation damping in a power transmission *** on this model,the effects of VSGs on low frequency oscillations are compared with the effects of SGs to reveal the mechanism of how VSGs infuence damping *** influence of each VSG control loop on oscillations is also analyzed in this ***,the low frequency oscillation risks with different types of VSGs are ***,experiments on a real-time laboratory(RT-LAB)platform are conducted to verify the small-signal analysis results.

关键词： Grid-forming inverters low frequency oscillation participation factor renewable electricity small-signal model virtual synchronous generator(VSG)

High-throughput phenotyping: Breaking through the bottleneck in future crop breeding

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The Crop Journal 2021年第3期9卷 633-645页

作者： peng song Jinglu Wang Xinyu Guo Wanneng Yang Chunjiang Zhao National Key Laboratory of Crop Genetic Improvement National Center of Plant Gene ResearchHuazhongAgricultural UniversityWuhan 430070HubeiChina Beijing KeyLab of Digital Plant Beijing Research Center for Information Technologyin AgricultureBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China

With the rapid development of genetic analysis techniques and crop population size,phenotyping has become the bottleneck restricting crop *** through this bottleneck will require phenomics,defined as the accurate,high-throughput acquisition and analysis of multi-dimensional phenotypes during crop growth at organism-wide levels,ranging from cells to organs,individual plants,plots,and *** we offer an overview of crop phenomics research from technological and platform viewpoints at various scales,including microscopic,ground-based,and aerial phenotyping and phenotypic data *** describe recent applications of high-throughput phenotyping platforms for abiotic/biotic stress and yield ***,we discuss current challenges and offer perspectives on future phenomics research.

关键词： High-throughput phenotyping Crop breeding Crop phenomics Phenotyping platform Data analysis