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Atmospheric and Oceanic Science Letters 2023年第5期16卷 68-74页

作者： Dubin Huan qing yan Ting Wei Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Meteorological Disaste//Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing Unversity of Information Science and TechnologyNanjing China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing China Undversty of Chinse Acadenry of Scdences Beljing Chuna

研究过去暖期西北太平洋热带气旋的变化有助于理解未来气候变暖情景下热带气旋的可能变化.本研究基于PMIP4多模式输出结果,分析了末次间冰期西北太平洋热带气旋大尺度生成因子的变化及相关机制.结果表明,末次间冰期西北太平洋风暴季潜... 详细信息

研究过去暖期西北太平洋热带气旋的变化有助于理解未来气候变暖情景下热带气旋的可能变化.本研究基于PMIP4多模式输出结果,分析了末次间冰期西北太平洋热带气旋大尺度生成因子的变化及相关机制.结果表明,末次间冰期西北太平洋风暴季潜在强度降低,湿熵亏损升高,绝对涡度减弱,中部垂直风切变增强,西南部减弱.进一步,基于生成潜势指数,指出末次间冰期西北太平洋生成潜势降低,这表明环境条件不利于热带气旋生成。

关键词：热带气旋末次间冰期 PMIP4

Template-directed synthesis of pyridazine-containing tetracationic cyclophane for construction of[2]rotaxane

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Chinese Chemical Letters 2017年第5期28卷 1013-1017页

作者： Qiu-Sheng Fang Ling Chen qing-yan Liu Department College of Chemistry and Chemical Engineering Key Laboratory of Functional Small Organic MoleculesMinistry of EducationInstitution Jiangxi Normal UniversityNanchang 330022China

Benefiting from its bent molecular structure,3,6-pyridazinyl contained tetracationic cyclophane（1） is synthesized by template-directed method with high isolated yield up to 92%.This template-directed strategy is fur... 详细信息

关键词： Tetracationic cyclophane Template effect Inclusion complex π-Stacking Rotaxane

Simulation for MSS-2 low-perigee elliptical orbit satellites:an example of lithospheric magnetic field modelling

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Earth and Planetary Physics 2023年第1期7卷 151-160页

作者： Yi Jiang Nils Olsen JiaMing Ou qing yan State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyTaipa 999078MacaoChina Division of Geomagnetism DTU SpaceNational Space InstituteTechnical University of DenmarkDiplomvej 3712800 Kgs.LyngbyDenmark

A future constellation of at least four geomagnetic satellites(designated Macao Scientific Satellite-1(MSS-1)and Macao Scientific Satellite-2(MSS-2))was recently proposed,to continue high-quality geomagnetic observations in the post-Swarm period,focusing especially on collecting data that will provide a global,three-dimensional survey of the geomagnetic *** this paper,we present a simulation of two years of orbits(2020.01.01-2022.01.01)of two satellites(tentatively denoted as MSS-2)that are constellated in elliptical(200×5,300 km)low-perigee *** comparing error variances of Gauss coefficients,we investigate the sensitivity of lithospheric magnetic field modelling to data collected from various satellite orbits,including a near circular reference orbit of 300×350km,and elliptical orbit of 180×5,300 km,220×5,300 km,200×3,000 km and 200×1,500 *** find that in two years the two MSS-2 satellites can collect 35,000 observations at altitude below 250 km,data that will be useful in advancing the quality of lithospheric magnetic field modelling;this number of observations reflects the fact that only 4.5%of the flight time of these satellites will be below250 km(just 6.4%of their flight time below 300 km).By combining observations from the MSS-2 satellites’elliptical orbits of 200×5,300km with observations from a circular reference orbit,the variance of the geomagnetic model can be reduced by a factor of 285 at spherical harmonic degree n=200 and by a factor of 1,300 at n=*** planned lower perigee of their orbits allows the new satellites to collect data at unprecedentedly lower altitudes,thus dramatically improving the spatial resolution of satellite-derived lithospheric field models,(up to 80%at n=150).In addition,lowering the apogee increases the time interval during which the satellites fly at near-Earth altitudes,thus improving the model predictions at all spherical harmonic degrees(around 52%-62%at n=150).The upper limit of the expected improvement to t

关键词： elliptical orbit satellite orbit simulation lithosphere field modelling spherical harmonics

Research progress on the NLRP3 inflammasome and its role in the central nervous system

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Neuroscience Bulletin 2013年第6期29卷 779-787页

作者： Shen-Bin Liu Wen-Li Mi yan-qing Wang Department of Integrative Medicine and Neurobiology Institute of Acupuncture ResearchState Key Laboratory of Medical NeurobiologyInstitutes of Brain ScienceShanghai Medical CollegeFudan University

The NLRP3 inflammasome,which consists of the NLRP3（nucleotide-binding oligomerization domain（Nod）–like receptor 3） scaffold,the ASC（apoptosis-associated speck-like protein containing a CARD） adaptor and procaspase-1,is assembled after the cytoplasmic LRRs（leucine-rich repeats） of NLRP3 sense pathogens or danger *** NLRP3 inflammasome controls the activation of the proteolytic enzyme ***-1 in turn regulates the maturation of the proinflammasome cytokines IL-1β and IL-18,which leads to an inflammatory *** inflammasome plays an important role in the development of Alzheimer’s disease and bacterial meningitis,and the NLRP3 inflammasome may become a new target for the prevention and treatment of central nervous system diseases.

关键词： NLRP3 inflammasome central nervous system

Crystal Structure and Luminescence of a Cd(Ⅱ) Compound Based on the 3,3’,5,5’-Tetrafluorobiphenyl-4,4’-dicarboxylate and Adenine Ligands

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Chinese Journal of Structural Chemistry 2020年第11期39卷 2041-2045页

作者： LIN Zhao-Ting WANG Yu-Ling LIU qing-yan College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

A one-dimensional(1 D) coordination polymer, [Cd2(TFBPDC)2(ad)2(CH3 OH)2]n(1), based on the 3,3’,5,5’-tetrafluorobiphenyl-4,4’-dicarboxylate(TFBPDC2-) and adenine(ad) ligands, was synthesized. Compound 1 crystallizes in the triclinic system, space group P1 with a = 9.7067(3), b = 9.9501(3), c = 11.6903(4) ?, α = 93.036(3), β = 107.793(3), γ = 107.107(3)°, V = 1014.77(6) ?3, Z = 2, C40H26F8N10O10Cd2, Mr = 1183.51, Dc = 1.937 g/cm3, μ = 1.160 mm-1, F(000) = 584, the final R = 0.0284 and wR = 0.0635 for 3791 observed reflections with Ⅰ> 2s(I). In 1, a pair of adenine(ad) ligands bridge two octahedrally coordinated Cd(Ⅱ) atoms to form a dinuclear [Cd2(ad)2] unit, which is linked by TFBPDC2- to generate a 1 D double chain. The neighboring chains are connected by N-H×××O hydrogen bonds to give a two-dimensional(2 D) layer, which is further linked by the O-H×××N hydrogen bonds to give a three-dimensional(3 D) supramolecular framework. IR spectrum, thermogravimetric analysis, and powder X-ray diffraction of 1 were provided. Compound 1 shows luminescent emission.

关键词： cadmium coordination polymer 3 3’ 5 5’-tetrafluorobiphenyl-4 4’-dicarboxylate adenine luminescence crystal structure

Sharp Estimates of p-Adic Hardy and Hardy-Littlewood-Pólya Operators

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Acta Mathematica Sinica,English Series 2013年第1期29卷 137-150页

作者： Zun Wei FU qing yan WU Shan Zhen LU Department of Mathematics Linyi University School of Mathematical Sciences Beijing Normal University

In this paper we get the sharp estimates of the p-adic Hardy and Hard^Littlewood-Pdlya operators on L^q （｜x｜apdx）. Also, we prove that the commutators generated by the p-adic Hardy operators （Hardy-Littlewood-Pdl... 详细信息

关键词： p-Adic Hardy operator p-Adic Hardy-Littlewood-P61ya operator central BMO function,Herz space

Solid FeS lubricant: a possible alternative to MoS2 for Cu–Fe-based friction materials

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International Journal of Minerals,Metallurgy and Materials 2017年第11期24卷 1278-1283页

作者： Tao Peng qing-zhi yan Xiao-lu Zhang Xiao-jiao Shi Laboratory of Special Ceramics and Powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

Molybdenum disulfide(MoS_2) is one of the most commonly used solid lubricants for Cu–Fe-based friction materials. Nevertheless, MoS_2 reacts with metal matrices to produce metal sulfides(e.g., FeS) and Mo during sintering, and the lubricity of the composite may be related to the generation of FeS. Herein, the use of FeS as an alternative to MoS_2 for producing Cu–Fe-based friction materials was investigated. According to the reaction principle of thermodynamics, two composites—one with MoS_2(Fe–Cu–MoS_2 sample) and the other with FeS(FeS–Cu_2S–Cu–Fe–Mo sample), were prepared and their friction behaviors and mechanical properties were compared. The results showed that MoS_2 reacted with the Cu–Fe matrix to produce FeS, metallic ternary sulfides, and Mo when sintered at 1050°C. The MoS_2–Cu–Fe and FeS–Cu_2S–Cu–Fe–Mo samples thereby exhibited similar characteristics with respect to phase composition, density, hardness, and tribological behaviors. Micrographs of the worn surfaces revealed that the stable friction regime for both composites stemmed from the iron sulfides friction layers rather than from the molybdenum sulfides layers.

关键词： friction materials solid lubricants iron sulfides molybdenum sulfides

Bacterial diversity in soils around a lead and zinc mine

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Journal of Environmental Sciences 2007年第1期19卷 74-79页

作者： HU qing QI Hong-yan ZENG Jing-hai ZHANG Hong-xun Department of Environmental Biotechnology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Five samples of soil collected from a lead and zinc mine were used to assess the effect of combined contamination of heavy metals on soil bacterial communities using a polyphasic approach including characterization of isolates by culture method, community level catabolic profiling in BIOLOG GN microplates, and genetic community fingerprinting by denaturing gradient gel electrophoresis of 16S rDNA fragments amplified by PCR from community DNA （PCR-DGGE）. The structure of the bacterial community was affected to a certain extent by heavy metals. The PCR-DGGE analysis of 16S rRNA genes showed that there were significant differences in the structure of the microbial community among the soil samples, which were related to the contamination levels. The number of bacteria and the number of denaturing gradient gel electrophoresis （DGGE） bands in the soils increased with increasing distance from the lead and zinc mine tailing, whereas the concentration of lead （Pb） and cadmium （Cd） was decreased. Heavily polluted soils could be characterized by a community that differs from those of lightly polluted soils in richness and structure of dominating bacterial populations. The clustering analysis of the DGGE profiles showed that the bacteria in all the five samples of soil belonged to three clusters. The data from the BIOLOG analysis also showed the same result. This study showed that heavy metal contamination decreased both the biomass and diversity of the bacterial community in soil.

关键词： BIOLOG system DGGE heavy metal microbial diversity soils

Mg-doped CaCO_(3)nanoarchitectures assembled by(441)high-index facets for efficient trace removal of Pb(Ⅱ)

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Rare Metals 2023年第2期42卷 525-535页

作者： Yu yan Yu-Bo Cui qing-yan Wang Zhong-Xuan Che Tong Liu An-Ran Li Wei Zhou School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing100191China

Removal of trace heavy metal ions puts high demands on designing adsorbents with favorable ***-plane engineering can provide controllable adsorption energy between surficial planes and ***,we have creatively synthesized Mg-doped CaCO_(3)nanoarchitectures assembled by layered sheets(Mg-CaCO_(3)LSs)with high-index facets of(441)through a facile wet chemical *** tests reveal that the layer-bylayer assembled sample exhibits a maximum Pb(II)adsorption capacity of 1961.9 mg·g^(-1),agreeing with the monolayer-adsorption Langmuir *** an initial Pb(II)ion concentration of 20 mg·L^(-1),the adsorption can achieve a high removal rate near 99.0%within 1 min,and the adsorption kinetics follows a chemisorption pseudo-second-order ***,the Mg-CaCO_(3)LSs show much-improved adsorption properties towards low-concentration Pb(II)ions,which could reduce the concentration from 1 mg·L^(-1)to~2.9μg·L^(-1)in 3 h(within 30 min decrease to less than 10μg·L^(-1),meeting drinking water standard from WHO).For comparison,the commercial CaCO_(3)and collected CaCO_(3)scale show much lower adsorption values with Pb(Ⅱ)ion residual concentration of~935.0 and~944.9μg·L^(-1)in 3 h,*** diffraction(XRD),energy dispersive spectroscopy(EDS),and inductively coupled plasma(ICP)characterizations on the Mg-CaCO_(3)LSs before and after adsorbing Pb(Ⅱ)confirm that the high removal performance could be ascribed to fast metal ion exchange and excellent physical adsorption contributed by high-index *** density functional theory(DFT)calculations also confirm that the much-enhanced adsorption kinetics benefits from the optimal adsorption of the(441)*** work will provide a feasible route to design highefficient low-cost adsorbents through crystal-plane engineering.

关键词： High-index plane Calcium carbonate High adsorption energy Trace Pb(Ⅱ)removal

Automatic identification and feature recognition of the metro-led underground space in China based on point of interest data

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Underground Space 2023年第2期9卷 186-199页

作者： Yun-Hao Dong Fang-Le Peng yang Du yan-qing Men Research Center for Underground Space and Department of Geotechnical Engineering Tongji UniversityShanghai 200092China Jinan Rail Transit Group Co. LTD.JinanShandong 250101China

Metro-led underground space(MUS)plays a crucial role in modern underground space *** studies have shown its great potential for high-quality urban ***,limited evidence about MUS was available on a national scale,resulting in incomplete and unsystematic knowledge of MUS *** interaction relationship between MUS and the surrounding built environment also remains *** fill the research gap,an automatic method for MUS identification and development features extraction was proposed based on point of interest *** applied the method to identify the MUS in 28 Chinese cities and estimated the development status of MUS in China for the first *** nationwide statistics of MUS and correlation analysis of development features were *** show that complex MUS(CMUS)share is significantly lower than that of simple ***,CMUS development in China is primarily dominated by public transport and does not have a solid functional link to its *** comparative analysis of MUS development in four primary urban agglomerations was also conducted,and their development char-acteristics were *** study aims to expand the planning toolkit and construct the MUS database,which sheds light on the data-driven planning for MUS.

关键词： Development features Metro-led underground space Point of interest