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Journal of Rare Earths 2021年第6期39卷 696-702,I0004页

作者： yi sui Xiaoyu Liu Changsheng Liu School of Materials Science and Engineering Northeastern UniversityShenyang 110004China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030China

A novel Fe-Y composite oxide(Fe:Y-6.5) nanocluster was synthesized by self-assembly *** α-Fe_(2)O_(3) and cubic-Y_(2)O_(3) nanocrystalline with diameter around 10 nm are homogeneously assembled to form a cluster architecture which are constituted of Fe6.5Y composite oxide *** oxygen vacancies are introduced with cubic-Y_(2)O_(3),and the oxygen vacancies as Fe^(3+)-V_(0)-Y^(3+) between α-Fe_(2)O_(3) and cubic-Y_(2)O_(3) nanocrystalline are generated by self-assembly *** hysteresis loops recorded by vibrating sample magnetometry at 273 K display a ferromagnetic order,related to the fact that Fe^(3+)-V_(o)-Y^(3+) act as defect centers in the bound magnetic polaron model for Fe-Y composite oxide *** ferromagnetic prope rties are proportional to oxygen vacancy co ntents,and maximum magnetization(M_(m)) value of the nano-cluster reaches 5.14 A·m^(2)/g.

关键词： Room temperature ferromagnetism Fe-Y oxide nano-cluster Self-assembly Oxygen vacancy Rare earths

A survey of weak stability boundaries in the Sun-Mars system

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Research in Astronomy and Astrophysics 2015年第3期15卷 376-392页

作者： Jian Li yi-sui Sun School of Astronomy and Space Science & Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education Nanjing University

We investigate the weak stability boundary （WSB） for a new primary, Mars, in the framework of the planar circular restricted 3-body problem, and also in the pla- nar bicircular restricted 4-body problem by including a perturbation due to Jupiter. For the sake of a simple stability/instability criterion, our computations have been done us- ing the equations of motion in polar coordinates. It is found that the relative size of the weakly stable sets around Mars is much larger than that of the Earth-Moon and the Sun-Jupiter systems, as the mass ratio of the Sun-Mars system is significantly smaller. We propose that this difference could be scaled by the Hill radius. In an enlarged view of the domain close to Mars, the geometry of the WSB has been presented for various parameters and compared to previous works. Our results also show that Jupiter＇s grav- itational force would strongly affect the Martian stable regions and should be taken into account to design a ballistic capture trajectory.

关键词： celestial mechanics

Investigation of cracking mechanism of the first tunnel lining during double-arch tunnel construction

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Underground Space 2024年第1期14卷 1-17页

作者： yi sui Xiaohui Cheng Zuozhou Zhao Weibin Ma Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China School of Civil Engineering Tsinghua UniversityBeijing 100084China

To solve the engineering problem of the first tunnel lining cracking caused by the second tunnel construction of double-arch highway tunnels,a research method combining distributed optical-fibre monitoring,inversion analysis and numerical simulation that can reflect lining cracking was *** fibres were laid on opposite sides of the steel arches inside the first tunnel *** optical-fibre monitoring was conducted continuously during the second tunnel *** on the fibre-optic strain profile,the lining cracking was deduced and warned in *** mechanical behaviour of the steel arch was investigated by the inversion analysis,which took into consideration the integrated impact of axial force and flexural moment.A two-dimensional(2D)load-structure method–based numerical model was established,considering the influence of different load distributions in each construction *** total strain rotating crack constitutive model was applied to reflect the cracking behaviour of concrete lining in the simulation,and the model was calibrated and verified in the *** analysis between the simulated strain distribution and the distributed optical-fibre monitoring results was carried *** deformation mode and crack distribution of the lining were *** cracking mechanism was ***,the second tunnel construction led to the loading at the top of the middle partition wall and the release of rock pressure in the first *** these load changes,the secondary lining of the first tunnel cracked on the inner side of the top of the middle partition wall owing to tension,and compression-bending failure occurred near the right arch ***,the influence of the parameters on the lining force was analysed,and a construction optimisation scheme was proposed.

关键词： Double-arch tunnel Cracking mechanism Distributed optical-fibre sensing Inversion analysis Total strain rotating crack model Loadstructure method

Collaborative force and shape control for large composite fuselage panels assembly

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Chinese Journal of Aeronautics 2023年第7期36卷 213-225页

作者： Zhanghao WANG Dongsheng LI Liheng SHEN yi sui Yunong ZHAI School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315832China COMAC Shanghai Aircraft Manufacturing Co. LtdShanghai 201324China

This study proposed a force and shape collaborative control method that combined method of influence coefficients(MIC)and the elitist nondominated sorting genetic algorithm(NSGA-II)to reduce the shape deviation caused by manufacturing errors,gravity deformation,and fixturing errors and improve the shape accuracy of the assembled large composite fuselage *** study used a multi-point flexible assembly system driven by hexapod parallel *** proposed method simultaneously considers the shape deviation and assembly load of the ***,a multi-point flexible assembly system driven by hexapod parallel robots was introduced,with the relevant variables defined in the control *** addition,the corresponding mathematical model was ***,MIC was used to establish the prediction models between the displacements of actuators and displacements of panel shape control points,deformation loads applied by the *** the modeling,the shape deviation of the panel and the assembly load were used as the optimization objectives,and the displacements of actuators were optimized using ***,a typical composite fuselage panel case study was considered to demonstrate the effectiveness of the proposed method.

关键词： Assembly Collaborative force and shape control Composite panel Hexapod parallel robots Method of influence coefficients

Local scour around bridge abutments under ice covered condition-an experimental study

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International Journal of Sediment Research 2015年第1期30卷 39-47页

作者： Peng WU Faye HIRSHFIELD Jue-yi sui Environmental Engineering Program University of Northern British Columbia

The local scour around bridge abutments has been an active research topic for many *** very few studies have been conducted regarding the impacts of ice cover on the local scour phenomenon around bridge abutments.A series of ice covered flume experiments were conducted in this *** shape factors of different abutment types in the local scour were *** ice cover,the shape factor for semi-circular abutments ranges from 0.66～*** different non-uniform sediments were used with D50s of 0.58 mm,0.50 mm,and0.47 mm *** types of ice cover,namely smooth and rough cover,were created to simulate the impacts of ice cover around the *** scour depth was analyzed under different *** contours of the scour holes were plotted to show the bed morphology and sediment deposition around bridge *** empirical relationship between maximum scour depth,densimetric Froude number and sediment size was developed.

关键词： Bridge abutment Ice cover Local scour Maximum scour depth

Is tenecteplase ready to replace alteplase to treat acute ischaemic stroke? The knowns and unknowns

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Stroke & Vascular Neurology 2022年第1期7卷 1-5页

作者： yi Dong yi sui Xin Cheng David Z Wang Department of Neurology Huashan Hospital Fudan UniversityShanghaiChina Department of Neurology Shenyang Brain HospitalShenyang Medical CollegeShenyangChina Department of Neurology The First People's Hospital of ShenyangShenyangChina Department of Neurology Barrow Neurological InstitutePhoenixArizonaUSA

Tenecteplase(TNKase,TNK-tPA or TNK)is a thrombolytic agent derived from the tissue plasminogen activator(tPA).It is a 527-amino acid glycoprotein developed by replacing three amino acids at the T,N and K positions of the glycoprotein structure of tPA under genetic recombinant *** replacing threonine 103 with asparagine,asparagine 117 with glutamine and a tetra-alanine at amino acids 296–299,TNK is about eightfold more potent in dissolving clot,80-fold higher resistance to plasminogen activator inhibitor-1 and 14-fold enhanced relative fibrin specificity,and with a longer half-life(20 min).1 Hence,TNK is administered as a single intravenous bolus.

关键词： technology replace replacing

Formation of the Kuiper Belt by Long Time-Scale Migration of Jovian Planets

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 588-596页

作者： Jian Li Li-Yong Zhou yi-sui Sun Department of Astronomy Nanjing University Nanjing 210093

The orbital migration of Jovian planets is believed to have played an important role in shaping the Kuiper Belt. We investigate the effects of the long time-scale （2 ×107 yr） migration of Jovian planets on the orbital evolution of massless test particles that are initially located beyond 28 AU. Because of the slowness of the migration, Neptune＇s mean motion resonances capture test particles very efficiently. Taking into account the stochastic behavior during the planetary migration and for proper parameter values, the resulting concentration of objects in the 3：2 resonance is prominent, while very few objects enter the 2：1 resonance, thus matching the observed Kuiper Belt objects very well. We also find that such a long time-scale migration is favorable for exciting the inclinations of the test particles, because it makes the secular resonance possible to operate during the migration. Our analyses show that the us secular resonance excites the eccentricities of some test particles, so decreasing their perihelion distances, leading to close encounters with Neptune, which can then pump the inclinations up to 20°.

关键词： celestial mechanics -- Kuiper Belt -- methods numerical -- solar system formation

Deep-learning-based extraction of the animal migration patterns from weather radar images

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Science China(Information Sciences) 2020年第4期63卷 59-68页

作者： Kai CUI Cheng HU Rui WANG yi sui Huafeng MAO Huayu LI Radar Research Laboratory School of Information and Electronics Beijing Institute of Technology Key Laboratory of Electronic and Information Technology in Satellite Navigation (Beijing Institute of Technology) Ministry of Education

Continental coverage and year-round operation of the weather radar networks provide an unprecedented opportunity for studying large-scale airborne migration. The broad and local-scale airborne information collected by these infrastructures can answer many ecological questions. However, extracting and interpreting the biological information from such massive weather radar data remains an intractable problem. Recently, many big-data problems have been solved using the deep learning technology. In this study, the biological information in the weather radar data is identified using the advanced deep learning method. The proposed method consists of two main parts, i.e., a rendering and casting procedure and an image segmentation procedure based on a convolutional neural network. The biological data are automatically extracted by rendering and mapping, image segmentation, and result masking. By analyzing the typical radar data from single and multiple stations, we partly reveal the intensity and speed of the migration pattern. We present the first feasibility study of the extraction of local and large-scale biological phenomena from the Chinese weather radar network data.

关键词： weather radar deep learning aerial animal migration pattern Chinese weather radar network

Fluvial geomorphology of the Middle Reach of the Huai River

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International Journal of Sediment Research 2014年第1期29卷 24-33页

作者： Bang-yi YU Peng WU Jue-yi sui Xing-ju YANG Jin NI Research Institute of Water Resources Engineering of Anhui Province Environmental Engineering Program University of Northern British Columbia

The Middle Reach of the Huai River（MRHR） flows northeast into the Hongzehu *** entering the Hongzehu Lake,the Huai River has a braided channel which is shallow and wide,and the riverbed has a negative *** on the characteristics of the MRHR,this river reach can be divided into the following sections:a quasi-straight（or mildly curved） section,a bend section,and a braided *** majority of the MRHR is *** this paper,several parameters are used to assess the geomorphology of the *** analyses are performed to establish a relationship between the span length "L" and channel width "B" for different channel *** relationship between the meandering length "S" and bankfull channel width "B" is also *** indicate that the bankfull channel width "B",the bankfull cross sectional area "A" and the average flow depth "H" are mainly dependent on the dominant discharge in the channel.A relationship is derived that describes the dependency of the curvature radius "R" on the dominant discharge "Q",water surface slope "J" and the turning angle;.

关键词： Braided channel Dominant discharge Huai River Channel pattern

Host compatibility interacts with seed dispersal to determine smallscale distribution of a mistletoe in Xishuangbanna,Southwest China

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Journal of Plant Ecology 2016年第1期9卷 77-86页

作者： Yahuang Luo yi sui Jianmin Gan Ling Zhang Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences No.19A Yuquan RoadBeijing 100049China

Aims Mistletoe infection between intra- and interspecific hosts can be restricted by seed dispersal, host–mistletoe compatibility and other factors, yet few studies have linked seed dispersal and seedling establishment together for understanding mistletoe plant distribution and demography together in different anthropogenic disturbance forest types at a local scale. The objectives of this study were to examine how three factors—seed disperser behavior, post-dispersal host compatibility and canopy cover—affect the spatial distribution of a generalist mistletoe Dendrophthoe pentandra (Loranthaceae) in plantation and rainforest within Xishuangbanna, Southwest *** observed mistletoe D. pentandra infection patterns at the scale of individual trees and sixteen 400-m2 forest plots in adjacent plantation and rainforest within Xishuangbanna. To elucidate what determines infection patterns at different scales and in different forest types, we observed the behavior of major avian seed dispersers and carried out a seed inoculation experiment to examine how post-dispersal compatibility and light incidence affect the infection of different *** FindingsDendrophthoe pentandra displayed an aggregated distribution and infected 10 species in our study site, with a significantly higher infection prevalence and intensity in the plantation than in the tropical forest. Different seed dispersers provided contrasting initial mistletoe templates: the specialist frugivore Dicaeum concolor (plain flowerpecker) preferred to fly between mistletoes in infected trees in the plantation and likely intensified existing infections. In contrast, the dietary generalist Pycnonotus jocosus(red-whiskered bulbul) was more likely to visit uninfected trees, thereby establishing new infections. Thus, seed dispersal appears to be an important determinant of the mistletoes distribution, with deposition patterns providing an initial distribution template and determining small-scale pattern

关键词： aggregation frugivory establishment seedling survival host-parasite interaction