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chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 563-572页

作者： A-li luo and {2.-heng zhao National astronomical observatories, chinese academy of sciences, beijing 100012 National astronomical observatories Chinese Academy of Sciences Beijing 100012

The Large Sky-Area Multi-Object Spectroscopic Telescope (LAMOST) under construction by the National astronomical observatories will yield up to four thousand multi-fiber spectra of stars and galaxies per field. The present series of papers describes the automated data-reduction pipe{2.ne currently being designed in order to cope with the anticipated flood of spectrographic data. In this pre{2.minary paper, we present an automated method for estimating the continuum level, the positions of strong {2.nes and the 4000 A break in galaxy spectra. In order to obtain detailed information on the continuum, we use a wavelet filter bank. After continuum fitting, our software searches for a 4000 A break and distinguishes between emission-{2.ne galaxies (ELGs) and non-ELGs according to whether the break is small or large. It then searches for strong {2.nes and measures the intensities of emission {2.nes and the equivalent widths of absorption {2.nes. For non-ELGs, the absorption {2.nes are identified automatically yielding redshift measurements.

关键词： methods: data analysis - techniques: spectroscopic - galaxies: emission lines - galaxies: absorption lines

The Coudé Echelle Spectrograph for the Xinglong 2.16m Telescope

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chinese Journal of Astronomy and Astrophysics 2001年第6期1卷 555-562页

作者： Gang zhao and Hong-Bin li National {2. observatories, chinese academy of sciences, beijing 100012 National astronomical observatories Chinese Academy of Sciences Beijing 100012

A brief description of the NAO coude echelle spectrograph mounted on the 2.16 m telescope at Xinglong station is given. This echelle spectrograph is located at the coudé focus with a prism cross disperser. The echelle image covers the spectral region from 330 to 1100 nm displayed in 80 spectral orders in one exposure through two light beams. With a slit height of 2.m, spectral orders are separated by 15 to 2. pixels in blue region and by 7 to 19 pixels in red region. Alternatively, two additional resolution modes corresponding to different focal length cameras with resolving power R 16000, 170 000 in the blue beam and R = 13000, 170 000 in the red beam could be provided by this spectrograph. The bias, dark, wavelength calibration, flat field and science exposure are described in details. The limiting magnitude for 1 hour exposure with an S/N ratio of 100 scales to V = 9.5 in the red path and to V = 7.2.in the blue path.

关键词： instrumentation: spectrographs methods: observational - techniques: spectroscopic

A network flow algorithm to position tiles for LAMOST

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Research in Astronomy and Astrophysics 2009年第11期9卷 1277-1284页

作者： Guang-Wei li and Gang zhao National {2. observatories, chinese academy of sciences, beijing 100012, China National astronomical observatories Chinese Academy of Sciences Beijing 100012 China

We introduce the network flow algorithm used by the Sloan Digital Sky Survey （SDSS） into the sky survey of the Large sky Area Multi-Object fiber Spectroscopic Telescope （LAMOST） to position tiles. Because fibers in LAMOST＇s focal plane are distributed uniformly, we cannot use SDSS＇ method directly. To solve this problem, firstly we divide the sky into many small blocks, and we also assume that all the targets that are in the same block have the same position, which is the center of the block. Secondly, we give a value to limit the number of the targets that the LAMOST focal plane can collect in one square degree so that it cannot collect too many targets in one small block. Thirdly, because the network flow algorithm used in this paper is a bipartite network, we do not use the general solution algorithm that was used by SDSS. Instead, we give our new faster solution method for this special network. Compared with the Convergent Mean Shift Algorithm, the network flow algorithm can decrease observation times with improved mean imaging quality. This algorithm also has a very fast running speed. It can distribute millions of targets in a few minutes using a common personal computer.

关键词： methods data analysis -- methods statistical

Potential industrial applications of photo/electrocatalysis: Recent progress and future challenges

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Green Energy & Environment 2024年第5期9卷 859-876页

作者： Jinhao li Jing Ren Shaoquan li Guangchao li Molly Meng-Jung li Rengui li Young Soo Kang Xiaoxin Zou yong luo Bin liu Yufei zhao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou324000China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China Department of Applied Physics The Hong Kong Polytechnic UniversityHong Kong999077China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyZhongshan Road 457Dalian116023China Environmental and Climate Technology Track of Korea Institute of Energy Korea Institute of Energy TechnologyNaju-siJeollanam do58217Republic of Korea State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun130012China

Nowadays,the rapid development of the social economy inevitably leads to global energy and environmental *** this reason,more and more scholars focus on the development of photocatalysis and/or electrocatalysis technology for the advantage in the sustainable production of high-value-added products,and the high efﬁciency in pollutants *** there is plenty of outstanding research has been put forward continuously,most of them focuses on catalysis performance and reaction mechanisms in laboratory *** industrial application of photo/electrocatalytic processes is still a challenge that needs to be overcome by social *** this regard,this review comprehensively summarized several explorations in theﬁeld of photo/electrocatalytic reduction towards potential industrial applications in recent *** attention is paid to the successful attempts and the current status of photo/electrocatalytic water splitting,carbon dioxide conversion,resource utilization from waste,etc.,by using advanced *** key problems and challenges of photo/electrocatalysis in future industrial practice are also discussed,and the possible development directions are also pointed out from the industry view.

关键词： Photocatalysis Electrocatalysis Industrial applications H2.economy

A review of ultrafast laser micro/nano fabrication:Material processing,surface/interface controlling,and devices fabrication

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Nano Research 2024年第7期17卷 6212-6230页

作者： heng Guo Jiawang Xie Guangzhi He Dezhi Zhu Ming Qiao Jianfeng Yan Jiachen Yu Jiaqun li Yuzhi {2. Ma luo Haoze Han State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable processing precision,diverse processing capabilities,and broad material *** processing abilities and applications of the ultrafast laser still need more *** the field of material processing,controlling the atomic scale structure in nanomaterials is *** effects exist in ultrafast laser surface/interface processing,making it difficult to modulate the nanostructure and properties of the surface/interface as *** the ultrafast laser fabrication of micro functional devices,the processing ability needs to be ***,we review the research progress of ultrafast laser micro/nano fabrication in the areas of material processing,surface/interface controlling,and micro functional devices *** useful ultrafast laser processing methods and applications in these areas are *** various processing effects and abilities,the ultrafast laser processing technology has demonstrated application values in multiple fields from science to industry.

关键词： ultrafast laser micro/nano fabrication material processing surface/interface controlling devices fabrication

Heterostructure VO2.VS2.tailored by one-step hydrothermal synthesis for stable and highly efficient Zn-ion storage

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Materials Futures 2024年第4期3卷 171-180页

作者： Enyan zhao Kesheng Gao Xuan {2. lin li Jinkui zhao Hongliang li College of Materials Science and Engineering Qingdao UniversityQingdao 266071People’s Republic of China Songshan Lake Materials Laboratory Dongguan 523808People’s Republic of China beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190People’s Republic of China School of Physical sciences Great Bay UniversityDongguan 523808People’s Republic of China

The increasing demand for advanced energy storage solutions has driven extensive research into Zn-ion batteries due to their safety,cost-effectiveness,and environmental *** study presents a synthesis and evaluation of VO2.VS2.hollow nanospheres as a novel cathode material for Zn-ion *** VO2.VS2.composite,synthesized via a one-step hydrothermal method,demonstrates a significant improvement in electrochemical *** material exhibits a reversible capacity of 468 mAh g-1 at 0.1 A g-1 and maintains a high capacity of 2.7 mAh g-1 at 1.0 A g-1 over 1000 cycles with a retention rate of 85%.Electrochemical analyses reveal enhanced charge transfer and Zn-ion storage,attributed to the synergistic effect and built-in electric field of the VO2.and VS2.***,the composite shows superior electrochemical kinetics,facilitating rapid ion transport and charge ***-situ Raman analysis confirms the reversible Zn-ion storage mechanism,further validating the composite’s structural stability during *** functional theory calculations further support these findings,indicating the composite’s potential for high-rate capability and long-term cycling *** research highlights the promise of VO2.VS2.hollow nanospheres in advancing the performance of aqueous Zn-ion batteries.

关键词： Zn-ion batteries vanadium-based cathode hollow nanospheres heterostructure pseudocapacitive

Spectroscopic study of globular clusters in the halo of M31 with the Xinglong 2.16 m telescope

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Research in Astronomy and Astrophysics 2011年第11期11卷 1298-1310页

作者： Zhou Fan1,2.Ya-Fang Huang1,2.Jin-Zeng li1,2.Xu Zhou1,2.Jun Ma1,2.Hong Wu1,2.Tian-Meng Zhang1,2.and yong-{2. zhao1,2.1 National astronomical observatories,chinese academy of sciences,beijing 100012,China 2.Key Laboratory of Optical Astronomy,National astronomical observatories,chinese academy of sciences,beijing 100012,China National astronomical observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

We present spectroscopic observations for 11 confirmed globular clusters(GCs) of M31 with the OMR spectrograph on the 2.16 m telescope at the Xinglong site of National astronomical observatories,{2. academy of *** of our sample clusters are located in the halo of M31 and the most remote one is out to a projected radius of 78.75 kpc from the galactic *** all our sample clusters,we measured the lick absorption-line indices and radial *** is noted that most GCs in our sample are distinct from the HI rotation curve of galaxy M31,especially for B514,MCGC5,H12.and B517,suggesting that most of our sample clusters do not have a kinematic association with the star-forming young disk of the *** separately fitted the absorption line indices from the updated stellar population model of Thomas et *** two different tracks of Cassisi and Padova,by applying the χ2.minimization *** fitting results show that all our sample clusters are older than 10 Gyr,and metal-poor(2.38 ≤ [Fe/H] ≤ 0.91 dex).After merging the spectroscopic metallicity of our work with the previously published ones,we extended the cluster sample out to a projected radius of 117 kpc from the galaxy's *** found the metallicity gradient exists for all the confirmed clusters with a slope of 0.02. ± 0.001 dex kpc ***,the slope turns out to be 0.018 ± 0.001 dex kpc 1 for all the halo clusters,which is much *** we only consider the outer halo clusters with rp > 2. kpc,the slope becomes 0.010 ± 0.002.dex kpc 1 and if one cluster G001 is excluded from the outer halo sample,the slope is 0.004 ± 0.002.dex kpc ***,we conclude that the metallicity gradient for M31's outer halo clusters is not significant,which agrees well with previous findings.

关键词： galaxies individual(M31) — galaxies star clusters — globular clusters general — star clusters general

Efficient and stable hybrid perovskite-organic light-emitting diodes with external quantum efficiency exceeding 40 per cent

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light(Science & Applications) 2024年第7期13卷 1364-1371页

作者： lingmei Kong Yun luo Qianqian Wu Xiangtian Xiao Yuanzhi Wang Guo Chen Jianhua Zhang Kai Wang Wallace CHChoy {2.-Biao zhao Hongbo li Takayuki Chiba Junji Kido Xu{2. Yang Key Laboratory of Advanced Display and System Applications of Ministry of Education Shanghai UniversityShanghai 200072China. Institute of Nanoscience and Applications Department of Electrical and Electronic EngineeringSouthern University of Science and TechnologyShenzhen 518055China. Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina. Department of Physics and Lakeside AR/VR Laboratory International Joint Research Center for Optoelectronic and Engineering ResearchYunnan UniversityKunming 650091China. Experimental Center of Advanced Materials School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China. Graduate School of Organic Materials Science Frontier Center for Organic MaterialsYamagata University4-3-16 JonanYonezawa 992–8510Japan

light-emitting diodes(LEDs)based on perovskite semiconductor materials with tunable emission wavelength in visible light range as well as narrow linewidth are potential competitors among current light-emitting display technologies,but still suffer from severe instability driven by electric ***,we develop a stable,efficient and highcolor purity hybrid LED with a tandem structure by combining the perovskite LED and the commercial organic LED technologies to accelerate the practical application of *** LED and organic LED with close photoluminescence peak are selected to maximize photon emission without photon reabsorption and to achieve the narrowed emission *** designing an efficient interconnecting layer with p-type interface doping that provides good opto-electric coupling and reduces Joule heating,the resulting green emitting hybrid LED shows a narrow linewidth of around 30 nm,a peak luminance of over 176,000 cd m^(−2.,a maximum external quantum efficiency of over 40%,and an operational half-lifetime of over 42.000 h.

关键词： diodes narrow quantum

Source apportionment and suitability evaluation of seasonal VOCs contaminants in the soil around a typical refining-chemical integration park in China

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Journal of Environmental sciences 2024年第3期137卷 651-663页

作者： Xu zhao Jing Meng Qianqian li Guijin Su Qifan Zhang Bin Shi lingwen Dai yong Yu Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of chinese academy of sciences Beijing 100049China State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring China National Environmental Monitoring CenterBeijing 100012China

Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing ***,in the process,seasonal effect on contamination pathways and accumulation of soil VOCs is often ***,Yanshan Refining-Chemical Integration Park,including a carpet,refining,synthetic rubber,and two synthetic resin zones,was selected for *** variations resulted in a gradual decrease of 31 VOCs in soil from winter to summer.A method of dry deposition resistance model coupling partitioning coefficient model was created,revealing that dry deposition by gas phase was the primary pathway for VOCs to enter soil in winter and spring,with 100 times higher fux than by particle *** profiles for five zones were built by gas sampling with distinct substance indicators screened,which were used for positive matrix factorization factors *** of the five zones were 14.9%,2..8%,13.6%,2..1%,and 2..6%in winter and 33.4%,12.5%,10.7%,2..9%,and 18.5%in spring,*** variation in the soil sorption capacity of VOCs causes inter-seasonal differences in *** better correlation between dry deposition capacity and soil storage of VOCs made root mean square and mean absolute errors decrease averagely by 8.8%and 5.5%in winter compared to *** study provides new perspectives and methods for the source apportionment of soil VOCs contamination in industrial sites.

关键词： Dry deposition resistance model Positive matrix factorization model Partitioning coefficient model Contamination pathway Source profile

Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 2. MeV on the Back-n at CSNS

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Nuclear Science and Techniques 2024年第2期35卷 85-93页

作者： Jie-Ming Xue Song Feng yong-Hao Chen Han Yi Min Xiao Pin-Jing Cheng Xin-Xiang {2. Rong {2.u Yi-Wei Yang Zi-Jie Han Da-Jun zhao Hao-Qiang Wang Bao-Qian {2. Ji-Rong zhao Lei-Xun Tang Wen luo Bo Zheng School of Nuclear Science and Technology University of South ChinaHengyang 421001China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-2. MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron *** energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission *** on-beam background was determined using Co,In,Ag,and Cd *** excitation function of ^(nat)Pb(n,tot)reaction below 2. MeV was calculated using the TALYS-1.96 nuclear-reaction modeling *** present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2.and BROND-3.1),and the theoretical calculation *** agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding *** measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy *** provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead.

关键词： Neutron-induced total cross section Natural lead Time-of-flight TALYS-1.96 CSNS Back-n white neutron beamline