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An Initial Analysis of a Strongly Lensed QSO Candidate Identified by LAMOST

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Research in Astronomy and astrophysics 2023年第10期23卷 349-356页

作者： Y.H.Chen M.Y.Tang H.Shu H.Tu Institute of astrophysics Chuxiong Normal UniversityChuxiong 675000China School of Physics and Electronical Science Chuxiong Normal UniversityChuxiong 675000China key laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650011China Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming 650091China Physics Department&shanghai key lab for astrophysics Shanghai Normal UniversityShanghai 200234China

From 2011 to 2021,LAMOST has released a total of 76,167 quasar *** try to search for gravitationally lensed QSOs by limiting coordinate differences and redshift differences of these *** name,brightness,spectrum,photometry and other information of each QSO will be visually checked *** attention should be paid to check whether there are groups of galaxies,gravitationally lensed arcs,Einstein crosses,or Einstein rings near the *** careful selection,we select LAMOST J160603.01+290050.8(A)and LAMOST J160602.81+290048.7(B)as a candidate and perform an initial *** A and B are336 apart and they display blue during photometric *** redshift values of components A and B are0.2%different,their Gaia_g values are 1.3%different,and their ugriz values are 1.0%or less *** the spectra covering from 3690 to 9100?,the emission lines of C II,Mg,Hγ,OⅢ,and Hβare present for both components A and B and the ratio of flux(B)to flux(A)from LAMOST is basically a constant,around ***,no galaxies have been found between components A and *** et *** them as binary *** we accidentally find a galaxy group near components A and *** the center of dark matter in the galaxy group is at the center between components A and B,components A and B are probably gravitationally lensed *** estimate that the Einstein mass is 1.46×10^(11)M_⊙and the total mass of the lens is1.34×10^(13)M_⊙.The deflection angle is 197 at positions A and B and the velocity dispersion is 261 km s^(-1).Theoretically,this candidate could be a pair of fold images of a strong lensing system by a galaxy group,and we will investigate the possibility when the redshifts of nearby galaxies are available.

关键词： gravitational lensing:strong (galaxies:)quasars:individual(LAMOST J1606+2900) techniques:imaging spectroscopy

Syntax-guided text generation via graph neural network

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Science China(Information Sciences) 2021年第5期64卷 67-76页

作者： Qipeng GUO Xipeng QIU Xiangyang XUE Zheng ZHANG shanghai key laboratory of Intelligent Information Processing School of Computer ScienceFudan University NYU shanghai and AWS shanghai AI lab

Text generation is a fundamental and important task in natural language processing. Most of the existing models generate text in a sequential manner and have difficulty modeling complex dependency structures. In this paper, we treat the text generation task as a graph generation problem exploiting both syntactic and word-ordering relationships. Leveraging the framework of the graph neural network, we propose the word graph model. During the process, the model builds a sentence incrementally and maintains syntactic integrity via a syntax-driven, top-down, breadth-first generation process. Experimental results on both synthetic and real text generation tasks show the efficacy of our approach.

关键词： text generation deep learning graph neural network dependency parsing

Effect of Ti（lll） Surface Defects on the Process of Photocatalytic Reduction of Hexavalent Chromium

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Chinese Journal of Chemistry 2017年第2期35卷 203-208页

作者： Hongxia Qin Yingying Bian Yaxi Zhang Longfei Liu Zhenfeng Bian Education Ministry key lab of Resource Chemistry and shanghai key laboratory of Rare Earth Functional Materials Shanghai Normal University Shanghai 200234 China

In this paper, the process of photocatalytic reduction of hexavalent chromium was investigated over Ti3＋- modified TiO2 photocatalysts. The Ti3＋ surface defects were repaired by annealing as-prepared sample at different temperatures to control the amount of Ti3＋ sites. The samples were characterized by SEM, XRD, BET, UV-Vis absorption, EPR and XPS. The results showed Ti3＋ defects were successfully doped in TiO2. The surface selective adsorption of hexavalent chromium [Cr2072 （Cr（VI））] and the desorption of trivalent chromium [Cr3＋（Cr（III））] were investigated during the process ofphotocatalytic reduction positive charges due to more Ti3＋ defects on the surface show a Accordingly, the surface positive reduction of Cr（VI）. charges controlled by the Ti3＋ Zeta potential results presented that the increased significant improvement for adsorption of Cr（VI）. defects play important roles in the photocatalytic

关键词： Ti3+ modification titanium dioxide photocatalytic reduction hexavalent chromium surface selective adsorption and desorption

Biomimetic Chiral Pyridoxal and Pyridoxamine Catalysts

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Chinese Journal of Chemistry 2019年第2期37卷 103-112,I0002页

作者： Jianfeng Chen Yong Ethan Liu Xing Gong Limin Shi Baoguo zhao The Education Ministry key lab of Resource Chemistry and shanghai key laboratory of Rare Earth Functional Materials Shanghai Normal UniversityShanghai 200234China

What is the most favorite and original chemistry developed in your research group? Vitamin B6-based biomimetic asymmetric catalysis. How do you get into this specific field? Could you please share some experiences with our readers? Enzymatic transformations are characterized by high efficiency, specific selectivities, and mild conditions, which attracts me to do some chemistry related to biological systems.

关键词： Biomimetic Chiral Pyridoxal Pyridoxamine Catalysts

NUMERICAL SIMULATION OF UNSTEADY TURBULENT FLOW INDUCED BY TWO-DIMENSIONAL ELEVATOR CAR AND COUNTER WEIGHT SYSTEM

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Journal of Hydrodynamics 2007年第6期19卷 720-725页

作者： SHI Li-qun LIU Ying-zheng JIN Si-yu CAO Zhao-min Power Machinery Engineering lab Key Lab of Education Ministry of China School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

A two-dimensional model of unsteady turbulent flow induced by high-speed elevator system was established in the present study. The research was focused on the instantaneous variation of the aerodynamic force on the car structure during traversing motion of the counter weight in the hoistway. A dynamic meshing method was employed to treat the multi-body motion system to avoid poor distortion of meshes. A comprehensive understanding of this significant aspect was obtained by varying the horizontal gap （δ =0.1m, 0.2m, and 0.3m） between the elevator car and the counter weight, and the moving speed （ U 0= 2m/s, 6m/s, and 10m/s） of the elevator system. A pulsed intensification of the aerodynamic force on the elevator car and subsequent appearance of large valley with negative aerodynamic force were clearly observed in the numerical results. In parameters studied （ δ =0.1m, U 0= 2m/s, 6m/s, 10m/s）, the peaked horizontal and vertical forces are respectively 7-11 and 4.3-5.65 times of that when the counter weight is far from the car. These results demonstrated the prominent influence of the traversing counter weight on aerodynamic force on the elevator car, which is of great significance to designers of high-speed elevator system.

关键词： high-speed elevator turbulent flow aerodynamic force Computational Fluid Dynamics (CFD)

Observation on Emitting Dislocation from Grain Boundary by TEM

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Journal of Materials Science & Technology 1998年第1期14卷 75-76页

作者： Junlin YIN (shanghai key lab. of Metal-Founctional Materials, shanghai Iron and Steel Research Institute, shanghai 200940, China) shanghai Iron & Steel Res Inst Shanghai Key Lab Met Founct Mat Shanghai 200940 Peoples R China

The observation on emitting dislocations from grain boundaries by TEM during Cu elongation has been performed. It is shown that there exists the 'ledge' at the grain boundaries in fee pure Cu, which is able to emit di... 详细信息

关键词： Observation on Emitting Dislocation from Grain Boundary by TEM Figure

MODELING OF THE PROCESS OF COMPOSITE ELECTRODEPOSITION

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中国有色金属学会会刊：英文版 1996年第4期6卷 26-30页

作者： Xie Yan Hu Wenbin Luo Shoufu Gu Mingyuan(State key laboratory of MMCS,shanghai Jiao Tong University,shanghai 200030) shanghai JIAO TONG UNIV STATE KEY LAB MMCSSHANGHAI 200030PEOPLES R CHINA

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关键词： composite eletrodeposition mathematical model of codeposition process

Impedance Analysis of Forging Process and Strategy Study on Compliance for Forging Manipulator

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 651-658页

作者： ZHANG Pu YAO Zhenqiang DU Zhengchun State key lab of Mechanical System and Vibration Shanghai Jiao Tong University

In the field of heavy forging, there are numerous researches on deformation rule in forging process by FEM simulation, however, not many scholars take the equipment constraint and the mutual reaction load between the forging manipulator clamp and the forging blank into account, which will impact on safety of manipulator body and quality of forging blank. This paper presents an impedance model to describe the load and formulates compliance strategies correspondingly to reduce the mutual reaction load for forging manipulator. Firstly, an FEM model of forging process is built. Meanwhile, the clamp of forging manipulator is added to the model as movement constraint and interaction part between the manipulator and the forming process. Secondly, a typical forging process is simulated by changing the movement constraint, and then an impedance model is established to describe the relationship between the load and movement constraint. Finally, two kinds of compliance strategies are formulated according to the impedance model, one is called free compliance, and the other is initiative/passive compliance. The simulation results show that compliance strategies reduce the load amounting to 5 000 kN in z direction between the manipulator clamp and the forging blank obviously, which may lead to serious accidents, such as the capsizing of forging manipulator, the fracture of manipulator clamp, and so on. The proposed research simulates the more real forging process, gets the initiative/passive compliance strategy which is more simple and suitable to the real producing and better for forming a forging process planning and control system in the modern production, and improves the quality and efficiency of heavy forging.

关键词： forging impedance compliance manipulator

Towards low emissions and high thermal efficiency of gasoline compression ignition engine under high loads by modulating the fuel reactivity and injection strategy

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Science China(Technological Sciences) 2020年第1期63卷 96-104页

作者： JIANG ChenXu LI ZiLong QIAN Yong LU XingCai key lab for Power Machinery and Engineering of MOE Shanghai Jiao Tong University

Gasoline compression ignition(GCI) is a practicable way to obtain low emissions and high thermal efficiency of gasoline-like fuels in internal combustion engines. In this paper, the research octane number(RON) and injection strategy were coordinated to optimize the GCI engine performance and emissions under high loads. The direct injection and port injection were used to achieve two injection strategies: direct injection(DI) and port injection plus direct injection(PIDI), and the primary reference fuels(PRF) with the RON of 60, 70, 80 and 90 were used. The results show that using lower RON fuels under high loads, DI mode can achieve higher efficiency, while PIDI mode can achieve lower combustion noise at an expense of slightly lower fuel economy. When the DI mode is converted to PIDI mode with a pre-injection ratio of 30%, using PRF70 under 12 bar and the exhaust gas recirculation(EGR) rate of 40%, the gross indicated thermal efficiency and the maximum pressure rise rate are reduced by 1% and by 2 bar/°CA, respectively, while the particle emissions also decrease significantly, thus achieving low emissions and high efficiency. However, under the same load and EGR rate, DI mode produces less regulated and unregulated emissions than PIDI mode. In addition, the effect of fuel RON was obvious, the lower RON fuels exhibit obvious three-stage heat release in PIDI mode, however, PRF90 with higher RON only exhibits two-stage heat release, and the peak value of the firststage heat release rate is also lower than those of other fuels.

关键词： gasoline compression ignition regulated and unregulated emissions injection strategy particle emissions fuel reactivity