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The Electromagnetic Compatibility between FAST and Public Mobile Communication Stations and its Cognitive Using Frequency Strategy

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Research in Astronomy and Astrophysics 2022年第12期22卷 183-197页

作者： jian Wang Yi-Bo zhao Ya-fei Shi Cheng Yang Yu-Long Hao jian-Min Sun School of Microelectronics Tianjin UniversityTianjin 300072China Qingdao Institute for Ocean Technology Tianjin UniversityQingdao 266200China Guizhou Radio Monitoring Station Guiyang 550005China

To master the electromagnetic environment characteristics around the Five-hundred-meter Aperture Spherical radio Telescope(FAST)and ensure a better ecological environment in the radio-quiet zone of FAST,we analyzed the radiation characteristics of the public communication stations around *** comparing the FAST received signal power from the communication stations and the interference protection threshold of the radio astronomy applications,we found that the total proportion of the communication stations exceeding the radio astronomy protection threshold is 69.01%.Furthermore,to fully protect the regular operation of FAST,we proposed four interference avoidance and frequency coordination strategies based on the cognitive ***:(1)increasing the operating frequency of the communication station;(2)adjusting the direction of the transmitter antennas;(3)reducing the height of the transmitter antennas;(4)decreasing the transmitting power of the communication *** a result,the impact on FAST can effectively be reduced,and the FAST's received power from the communication stations will be lower than the radio astronomy protection threshold by using the above mentioned four *** the analysis of the experiment,the prediction is consistent with the overall trend of the measurement,and using frequency strategies can significantly reduce the signal power at the receiving ***,we construct a quality evaluation system for frequency coordination and analyze the satisfaction of the four strategies under the four *** results show that adjusting the direction of the transmitter antennas has better satisfaction,and the maximum satisfaction is *** above research results can be further expanded to potentially improve the electromagnetic ecological environment around FAST and support the regular operation of FAST.

关键词： methods:analytical methods:statistical telescopes

Conceptual design and safety characteristics of a new multi-mission high flux research reactor

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Nuclear Science and Techniques 2023年第3期34卷 9-24页

作者： Wei Xu jian Li Heng Xie Zhi-Hong Liu Jing zhao fei Xie Lei Shi School of Nuclear Science and Engineering Beijing Key Laboratory of Passive Safety Technology for Nuclear EnergyNorth China Electric Power UniversityBeijing 102206China Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China

Research reactors with neutron fluxes higher than 10^(14) n cm^(−2) s^(−1) are widely used in nuclear fuel and material irradiation,neutron-based scientific research,and medical and industrial isotope *** high flux research reactors are not only important scientific research facilities for the development of nuclear energy but also represent the national comprehensive technical *** has several high flux research reactors that do not satisfy the requirements of nuclear energy development.A high flux research reactor has the following features:a compact core arrangement,high power density,plate-type fuel elements,a short refueling cycle,and high coolant velocity in the *** characteristics make it difficult to simultaneously realize high neutron flux and optimal safety margin.A new multi-mission high flux research reactor was designed by the Institute of Nuclear and New Energy Technology at Tsinghua University in China;the reactor can simul-taneously realize an average neutron flux higher than 2.0×10^(15) n cm^(−2) s^(−1) and fulfill the current safety *** high flux research reactor features advanced design concepts and has sufficient safety margins according to the preliminary safety *** on the analysis of the station blackout accident,loss of coolant accident,and reactivity accident of a single-control drum rotating out accidently,the maximum temperature of the cladding surface,minimum departure from nucleate boiling ratio,and temperature difference to the onset of nucleate boiling temperature satisfy the design limits.

关键词： High flux research reactor Neutron flux Safety analysis Maximum temperature of cladding surface Departure from nucleate boiling ratio

Using highly concentrated chloride solutions to leach valuable metals from cathode-active materials in spent lithium-ion batteries

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Rare Metals 2021年第7期40卷 1971-1978页

作者： Ai-fei Yi zhao-Wu Zhu Ya-Hui Liu jian Zhang Hui Su Tao Qi National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 101407China

This study focused on the extraction of valuable metals from the cathode-active materials in spent lithiumion batteries using a high-concentration chloride *** effects of the concentrations of ammonium chloride(NH4 Cl),hydrochloric acid(HCl),and reductants such as hydrogen peroxide(H_(2)O_(2))and urea(CO(NH_(2))_(2))on metal extraction and chlorine production were studied *** leaching mechanism was analyzed,and a leaching model was *** was found that the addition of solid NH4 Cl to an HCl solution significantly improved the metal extraction capability of the latter and reduced the formation of chlorine gas by 96.0%compared to that only using *** activation energies for leaching Li,Ni,Co,and Mn were determined to be 30.4,38.5,30.6,and 38.2 kJ·mol^(-1),*** study demonstrates an environmentally friendly method for recycling metal resources from cathode-active materials and furthers understanding of how NH4 Cl inhibits chlorine production when leaching with mixed solutions of HCl and NH4 Cl.

关键词： Lithium-ion batteries Hydrochloric acid Ammonium chloride Chlorine gas

Comparative Analysis of Eubacterial DNA Polymerase III Alpha Subunits

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Genomics, Proteomics & Bioinformatics 2006年第4期4卷 203-211页

作者： Xiao-Qian zhao jian-fei Hu and Jun Yu Beijing Institute of Genomics Chinese Academy of SciencesBeijing 101300China Graduate School ofChinese Academy of Sciences Beijing 100049China College of Life Sciences Peking UniversityBeijing100871China James D.Watson Institute of Genome Sciences Zhejiang UniversityHangzhou 310008China.

DNA polymerase Ⅲ is one of the five eubacterial DNA polymerases that is responsible for the replication of DNA duplex. Among the ten subunits of the DNA polymerase Ⅲ core enzyme, the alpha subunit catalyzes the reaction for polymerizing both DNA strands. In this study, we extracted genomic sequences of the alpha subunit from 159 sequenced eubacterial genomes, and carried out sequence- based phylogenetic and structural analyses. We found that all eubacterial genomes have one or more alpha subunits, which form either homodimers or heterodimers. Phylogenetic and domain structural analyses as well as copy number variations of the alpha subunit in each bacterium indicate the classification of alpha subunit into four basic groups: polC, dnaE1, dnaE2, and dnaE3. This classification is of essence in genome composition analysis. We also consolidated the naming convention to avoid further confusion in gene annotations.

关键词： DNA polymerase III alpha subunit dnaE polC

Statistical analysis of ocular monochromatic aberrations in Chinese population for adaptive optics ophthalmoscope design

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Journal of Innovative Optical Health Sciences 2017年第1期10卷 84-93页

作者： Junlei Zha fei Xiao jian Kang Haoxin zhao Yun Dai Yudong Zhang The Laboratory on A daptive Optics Institute of Optics and Electronics Chinese A cademy of Sciences Chengdu 610209 P.R.China The Key Laboratory on Adaptive Optics Chinese Academy of Sciences Chengdu 610209 P.R.China University of Chinese Academy of Sciences Beijing 100049 P.R.China

It is necessary to know the distribution of the Chinese eye's aberrations in clinical environment to guide high-resolution retinal imaging system design for large Chinese population *** collected the monochromatic wave aberration of 332 healthy eyes and 344 diseased eyes in Chinese population across a 6.0-mm *** aberration statistics of Chinese eyes including healthy eyes and diseased eyes were analyzed,and some differences of aberrations between the Chinese and European race were *** this basis,the requirement for adaptive optics(AO)correction of the Chinese eye's monochromatic aberrations was *** result showed that a stroke of 20μm and ability to correct aberrations up to the 8th Zernike order were needed for reflective wavefront correctors to achieve near difraction-limited imaging in both groups for a reference wavelength of 550 nm and a pupil diameter of *** verify the:analysis mentioned above,an A0 floodillumination system was established,and high-resolution retinal imaging in vivo was achieved for Chinese eye including both healthy and diseased eyes.

关键词： Ocular aberrations adaptive optics retinal imaging.

A new heuristic for task scheduling in heterogeneous computing environment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第12期9卷 1715-1723页

作者： Ehsan Ullah MUNIR jian-zhong LI Sheng-fei SHI zhao-nian ZOU Qaisar RASOOL School of Computer Science and Technology Harbin Institute of TechnologyHarbin 150001China Department of Computer Science COMSATS Institute of Information TechnologyWah Cantt 47040Pakistan

Heterogeneous computing (HC) environment utilizes diverse resources with different computational capabilities to solve computing-intensive applications having diverse computational requirements and constraints. The task assignment problem in HC environment can be formally defined as for a given set of tasks and machines, assigning tasks to machines to achieve the minimum makespan. In this paper we propose a new task scheduling heuristic, high standard deviation first (HSTDF), which considers the standard deviation of the expected execution time of a task as a selection criterion. Standard deviation of the ex- pected execution time of a task represents the amount of variation in task execution time on different machines. Our conclusion is that tasks having high standard deviation must be assigned first for scheduling. A large number of experiments were carried out to check the effectiveness of the proposed heuristic in different scenarios, and the comparison with the existing heuristics (Max-min, Sufferage, Segmented Min-average, Segmented Min-min, and Segmented Max-min) clearly reveals that the proposed heuristic outperforms all existing heuristics in terms of average makespan.

关键词： Heterogeneous computing Task scheduling Greedy heuristics High standard deviation first (HSTDF) heuristic

Colorimetric detection of D-amino acids based on anti-aggregation of gold nanoparticles

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Chinese Chemical Letters 2014年第7期25卷 995-1000页

作者： Long-fei Yuan Yu-jian He Hong zhao Ying Zhou Pei Gu College of Chemistry and Chemical Engineering University of Chinese Academy of Sciences State Key Laboratory of Natural and Biomimetic Drugs Peking University

A new method has been proposed to realize the visual detection of D-amino acids （DAAs） via the antiaggregation of 4-mercaptobenzoic acid modified gold nanoparticles （AuNPs） in the presence of D-amino acid oxidase （DAAO）. The negatively charged AuNPs were prepared using sodium citrate as a reducer and stabilizer. The presence of 4-mercaptobenzoic acid （4-MBA） and Cu2＋ induces the aggregation of AuNPs, resulting in a color change from ruby red to royal purple. However, DAAO could oxidize DAAs to generate H2O2. In the presence of H2O2, the mercapto （-SH） group in 4-mercaptobenzoic acid can be oxidized to form a disulfide （-S-S-） bond. Based on these facts, the pre-incubation of DAAs and 4-mercaptobenzoic acid with DAAO would significantly reduce the concentration of free 4-mercaptobenzoic acid molecules, thus the aggregation of AuNPs was interrupted since due to the lack of inducer. As the concentration of DAAs increases, the color of the AuNPs solution would progress from royal purple to ruby red. Consequently, DAAs could be monitored by the colorimetric response of AuNPs using a UV-vis spectrophotometer or even naked eyes. This DAAO mediated visual detection method could determine D- alanine （D-Ala） as a representative DAA with concentrations ranging from 1.5 × 10^-7mol L 1 to 3.0 × 10^-5 mol L^-1, and the detection limit was as low as 7.5 × 10^-8 mol L^-1. The proposed method is convenient, low-cost and free of complex equipment, making it feasible to analyze the concentration of D-AIa in real samples of β-amyloid peptide （Aβ1-42）.

关键词： Gold nanoparticles D-Amino acids D-Amino acid oxidase Anti-aggreagtion Colorimetric detection

Role Dynamic Allocation of Human-Robot Cooperation Based on Reinforcement Learning in an Installation of Curtain Wall

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Computer Modeling in Engineering & Sciences 2024年第1期138卷 473-487页

作者： Zhiguang Liu Shilin Wang jian zhao jianhong Hao fei Yu School of Control and Mechanical Engineering Tianjin Chengjian UniversityTianjin300384China Comprehensive Business Department CATARC(Tianjin)Automotive Engineering Research Institute Co.Ltd.300339China School of Mechanical Engineering Hebei University of TechnologyTianjin300130China

A real-time adaptive roles allocation method based on reinforcement learning is proposed to improve humanrobot cooperation performance for a curtain wall installation *** method breaks the traditional idea that the robot is regarded as the follower or only adjusts the leader and the follower in *** this paper,a self-learning method is proposed which can dynamically adapt and continuously adjust the initiative weight of the robot according to the change of the ***,the physical human-robot cooperation model,including the role factor is ***,a reinforcement learningmodel that can adjust the role factor in real time is established,and a reward and actionmodel is *** role factor can be adjusted continuously according to the comprehensive performance of the human-robot interaction force and the robot’s Jerk during the repeated ***,the roles adjustment rule established above continuously improves the comprehensive *** of the dynamic roles allocation and the effect of the performance weighting coefficient on the result have been *** results show that the proposed method can realize the role adaptation and achieve the dual optimization goal of reducing the sum of the cooperator force and the robot’s Jerk.

关键词： Human-robot cooperation roles allocation reinforcement learning

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU jian-Qiang MA zhao-Peng CHENG Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions