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VIBI Observations of Two Quasars at 1.3cm

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天文研究与技术 1999年第S1期 299-304页

作者： Su Bumei, li yongsheng ( Yunnan Observatory, The {2. academy of sciences, Kunming 650011, china ) ( national astronomical Observatories, The {2. academy of sciences, beijing {12., china ) Braath L.B. ( Center for Imaging Technologies, Halmst

The quasars, 0748+12. and 2.51+158 (3C 454 3),have been observed at 1 3cm by using a global VLBI network. We have obtained the images of the quasars with a resolution higher than 0″ 001. The brightness distribution is revealed in the nuclear region of the quasars. The radio emission FWHM from 0748+12. is 0 61×0 2. mas. 2.51+158 shows a nucleus-jet structure, and the nuclear region is elongated in the direction PA=-130°, The quasar can be fitted with 4 Gaussian components. The most west and east components are separated by 0 8mas (3pc). The integrated flux density in the nuclear region is 6 138Jy. The most east component shows the highest brightness, and its flux is ～4 11Jy (in 67% of the total detected flux), concentrated in the area of 0 16×0 01 mas. This causes the brightness temperature up to 2.6×10 12.K.

关键词： VIBI Observations of Two Quasars at 1.3cm

Observations of Ultraluminous IRAS Galaxies at 2.cm

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天文研究与技术 1999年第S1期 305-308页

作者： li yongsheng, Su Bumei ( Yunnan Observatory, The {2. academy of sciences, Kunming 650011, china ) ( national astronomical Observatories, The {2. academy of sciences, beijing {12., china ) Norris R.P. (Australia Telescope national Facility,

An ultraluminous IRAS galaxy sample has been observed at 2.cm using the Australia Compact Array (AT). The far infrared luminosity in the sample, log L FIR (L ⊙), is>11 8 ( H 0=50 km s -1 Mpc -1 , q 0=0 5 ). (Radio emission is detected from 19 sources among 37 IRAS galaxies. The radio parameters, for example, peak position, radio flux, etc, are obtained. The radio power P 2.cm in the sample is in the range 2. 92.cm (W/Hz) 2. 8. The paper presents the preliminary observational results on the sample at 2.cm.

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The Simulation of GEO Satellite Trajectory

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The Simulation of GEO Satellite Trajectory

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

第三届中国卫星导航学术年会

作者： Zhaorui Wang*, Jie Zhang, Shengming li, Xiaolan Wang national {2. Observatories, chinese academy of sciences, beijing 100012, china

The space segment of modern GNSS usually is a mixed constellation, which consists of MEO, GEO and IGSO satellites. During the development of satellite signal simulation system, the simulation of trajectory of satellite is necessary. For GEO satellite, the orbital motion equation in ECEF coordinates is derived, and the position and velocity of satellite are obtained in terms of Runge-Kutta numerical algorithm to realize the required trajectory simulation. The validity is verified with real BD1 and CAPS satellites measurements.

关键词： GEO Space trajectory Simulation Runge-Kutta

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Rare Metals 2024年第1期43卷 175-185页

作者： Jin-Xiao Zheng Zi-An Zhou Tiao Feng Hui li Cheng-Hua Sun NüWang Yang Tian yong Zhao Shu-Yun Zhou Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of chinese academy of {2. Beijing 100049China Laboratory of Bioinspired Smart Interfacial Science and Technology of the Ministry of Education Beijing Key Laboratory of Bioinspired Energy Materials and DevicesSchool of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China Department of Engineering Physics Tsinghua University and Key Laboratory of Particle and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China e-mail:yangt@***

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and ***, we designed a manganese-doped two-dimensional(2.) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32.mm × 32.mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

关键词： Two-dimensional perovskite Hydrophobic Scintillators Underwater X-ray imaging Underwater nondestructive testing technology

Biogenic volatile organic compounds dominated the near-surface ozone generation in Sichuan Basin,china,during fall and wintertime

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Journal of Environmental sciences 2024年第7期141卷 215-224页

作者： Dasheng Huang Qing li Yan Han Shi-yong Xia Jiawei Zhou Hanxiong Che Keding Lu Fumo Yang Xin Long Yang Chen Research Center for Atmospheric Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China College of Resources and Environment Chongqing SchoolUniversity of the Chinese Academy of Sciences(UCAS Chongqing)Chongqing 400714China College of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing 404199China Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate SchoolLishui RoadNanshan DistrictShenzhen 518055China SKL-ESPC and BIC-ESAT College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China College of Architecture&Environment Sichuan UniversityChengdu 610065China

The complex air pollution driven by both Ozone(O_(3))and fine particulate matter(PM2.5)sig nificantly influences the air quality in the Sichuan Basin(SCB).Understanding the O_(3)for mation during autumn and winter is necessary to understand the atmospheric oxidative ***,continuous in-site field observations were carried out during the late summer,early autumn and winter of 2.2. in a rural area of *** total volatile organic compounds(VOCs)concentration reported by a Proton-Transfer-Reaction Time-of Flight Mass Spectrometry(PTR-ToF-MS)were 13.66±9.75 ppb,5.50±2.64 ppb,and 9.41±5.11 ppb in late summer,early autumn and winter,*** anthropogenic VOCs(AVOCs)and biogenic VOCs(BVOCs)were 8.48±7.92.ppb and 5.18±2.99 ppb in late sum mer,3.31±1.89 ppb and 2.19±0.93 ppb in autumn,and 6.2.±3.99 ppb and 3.2.±1.2.ppb in winter.A zero-dimensional atmospheric box model was employed to investigate the sensitivity of O_(3)-precursors by relative incremental reactivity(RIR).The RIR values of AV OCs,BVOCs,carbon monoxide(CO),and nitrogen oxides(NOx)were 0.31,0.71,0.09,and-0.36 for late summer,0.2.,0.59,0.2.,and-0.38 for early autumn,and 0.30,0.64,0.33 and-0.70 for winter,and the results showed that the O_(3)formation of sampling area was in the VOC-limited region,and O_(3)was most sensitive to BVOCs(with highest RIR values,>0.6)This study can be helpful in understanding O_(3)formation and interpreting the secondary formation of aerosols in the winter.

关键词： VOCs PTR-MS Model Ozone

Design of the CAPS Navigation and Communication Incorporated Terminals

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Design of the CAPS Navigation and Communication Incorporated...

Decametric Response to the Great Impacts

第三届中国卫星导航学术年会

作者： li shengming 1, 2., Hou jinshuang 1 , Wang zhaorui 1 , Fan jiangtao 1, 2.1 national {2. Observatories, chinese academy of sciences, beijing 100012, china 2.Graduate University of chinese academy of sciences, beijing 100049, china

Based on the chinese Area Positioning System （CAPS）, the paper gives a solution of terminal which incorporate satellite positioning and bi-direction message communication functions. With the small beam shaped antenna, the terminal can send back the kinetic carrier position and realize bi-direction communicate without track the satellite. The software and hardware of the terminal and the system signal structure of CAPS are also introduced. Analysis on the carborne experiments positioning and communication data shows that the designed terminal is suitable to the navigation and communication applications of moving vehicles, which support a new approach for the monitor and communication of ships and vehicles.

关键词： chinese Area Positioning System Navigation and Communication Incorporated Terminal Message Communication Signal Structure

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紫金山天文台台刊 1996年第2期15卷 3-9页

作者： Han Jin-lin,Zhang Zi-zhen,Chen Hong-sheng,li Qi-bin{2. astronomical Obseruatory,chinese academy of sciences.beijing 100080,P.R.china

During the impact week,we monitored the decametric responses of collisions of fragments of comet Shoemaker-Levy 1993e (SL-9) on Jupiter,three strong bursts which are undoubtedly related to the impacts of fragments of ... 详细信息

关键词： Jupiter P/comet/SL9.

Cationic ordering transition in oxygen-redox layered oxide cathodes

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Carbon Energy 2024年第1期6卷 197-206页

作者： Xinyan li Ang Gao Qinghua Zhang Hao Yu Pengxiang Ji Dongdong Xiao Xuefeng Wang Dong Su Xiaohui Rong Xiqian Yu Hong li {2.-Sheng Hu lin Gu beijing national Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijingChina College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijingChina beijing national Center for Electron Microscopy and Laboratory of Advanced Materials School of Materials Science and EngineeringTsinghua UniversityBeijingChina beijing Advanced Innovation Center for Materials Genome Engineering Huairou DivisionInstitute of PhysicsChinese Academy of SciencesBeijingChina

Understanding the structural origin of the competition between oxygen 2. and transition-metal 3d orbitals in oxygen-redox(OR)layered oxides is eminently desirable for exploring reversible and high-energy-density li/Na-ion ***,we reveal the correlation between cationic ordering transition and OR degradation in ribbon-ordered P3-Na_(0.6)li_(0.2.Mn_(0.8)O_(2. via in situ structural *** two different voltage windows,the OR capacity can be improved approximately twofold when suppressing the in-plane cationic ordering *** find that the intralayer cationic migration is promoted by electrochemical reduction from Mn^(4+)to Jahn–Teller Mn^(3+)and the concomitant NaO_(6) stacking transformation from triangular prisms to octahedra,resulting in the loss of ribbon ordering and electrochemical ***-principles calculations reveal that Mn^(4+)/Mn^(3+)charge ordering and alignment of the degenerate eg orbital induce lattice-level collective Jahn–Teller distortion,which favors intralayer Mn-ion migration and thereby accelerates OR *** findings unravel the relationship between in-plane cationic ordering and OR reversibility and highlight the importance of superstructure protection for the rational design of reversible OR-active layered oxide cathodes.

关键词： cationic ordering layered oxide cathodes oxygen redox sodium-ion batteries

Generation of mitochondrial replacement monkeys by female pronucleus transfer

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Zoological Research 2024年第2期45卷 292-298页

作者： Chun-Yang li Xing-Chen liu Yu-Zhuo li Yan Wang Yan-Hong Nie Yu-Ting Xu Xiao-Tong Zhang yong Lu Qiang Sun Institute of Neuroscience Center for Excellence in Brain Science and Intelligence TechnologyState Key Laboratory of NeuroscienceChinese Academy of SciencesShanghai 200031China Key Laboratory of Genetic Evolution and Animal Models Chinese Academy of SciencesKunming 650201China University of chinese academy of {2. Beijing 100049China

Mutations in mitochondrial DNA(mtDNA)are maternally inherited and have the potential to cause severe *** replacement therapies,including spindle,polar body,and pronuclear transfers,are promising strategies for preventing the hereditary transmission of mtDNA *** pronuclear transfer has been used to generate mitochondrial replacement mouse models and human embryos,its application in non-human primates has not been previously *** this study,we successfully generated four healthy cynomolgus monkeys(Macaca fascicularis)via female pronuclear *** individuals all survived for more than two years and exhibited minimal mtDNA carryover(3.8%–6.7%),as well as relatively stable mtDNA heteroplasmy dynamics during *** successful establishment of this nonhuman primate model highlights the considerable potential of pronuclear transfer in reducing the risk of inherited mtDNA diseases and provides a valuable preclinical research model for advancing mitochondrial replacement therapies in humans.

关键词： Non-human primates Mitochondrial replacement Female pronuclear transfer