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Modes of occurrence and pre-concentration of rare earth elements in No.17 coal in Liupanshui coalfield,China

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Journal of Rare Earths 2022年第8期40卷 1323-1332页

作者： Bo yang Chen Cheng yuanxin Li Wei Cheng Jingkun Zang Xiangping Lai Xiaorui Wang College of Mining Guizhou UniversityGuiyang 550025China National&Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas Guiyang 550025China Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources Guiyang 550025China Guizhou Panjiang Clean Coal Co. Ltd.Liupanshui 553000China

Rare earth elements(lanthanide and yttrium,abbreviated as REY) provide important support for national security,energy production,environmental protection and economic growth.In recent years,many studies have shown that the content of REY in some coal or coal by-products is close to or even higher than that in traditional REY ore,which makes coal a potential source of REY.This study took the No.17 coal of Panzhou mining area in Liupanshui coal field as the research object,and the content and occurrence modes of REY in raw coal and 7 density fraction samples were studied.The results show that the content of REY in the raw coal reaches 220.67 μg/g,which is significantly higher than the average REY content in the world coal and Chinese coal as reported in the literature.Gravity separation has a certain pre-enrichment effect on REY and the fraction sample> 1.8 g/cm~3 has the highest REY of 426.27 μg/g(equal to rare earth oxide 0.1%).Study on correlation between REY and ash yields reveals that the organic affinity of the light rare earth is higher than that of the medium rare earth and the heavy rare earth.As shown by X-ray diffraction(XRD) and X-ray flouresence spectroscopy(XRF),the major minerals in coal are kaolinite,quartz and calcite,and the content of REY in coal is significantly related to Al,Si and kaolinite,which implies that REY occur mainly in kaolinite.Laser ablation inductively coupled plasma mass spectroscopy(LA-ICP-MS) was adopted to determine chemical composition of micro-zone in kaolinite in coal and the results show that there is no obvious correlation between REY and the contents of Al and Si.This indicates that the REY occur probably in the form of adsorption.The research results provide a scientific reference for the potential extraction of the associated REY in the coal.

关键词： Coal Rare earth elements Occurrence mode Kaolinite Pre-concentration

A new approach of extracting vegetation points from urban airborne LiDAR data

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Global Geology 2018年第3期21卷 194-202页

作者： CUI Shaochen yang yuanxin yang Guodong ZHANG Xuqing College of Geo-Exploration Science and Technology Jilin University Air Force Academy Institute of Engineering Design

Urban vegetation has been an important indicator for the evaluation of eco-cities,which is of great significance to promote eco-city construction. We study and discuss the commonly used urban vegetation extraction methods. The extraction of vegetation points in this study is completed through mathematical statistics,mean-square error,successive differences and iterative algorithm which are based on the analysis of different spatial morphological characteristics in urban point clouds. Linyi,a city of Shandong Province in China,is selected as the study area to test this method and the result shows that the proposed method has a strong practicality in urban vegetation point cloud extraction. Only 3D coordinate properties of the LiDAR point clouds are used in this method and it does not require additional information,for instance,return intensity,which makes the method more applicable and operable.

关键词：城市建设激光雷达植被数据提取抽取方法数学统计 eco 指示物

Hydrothermal synthesis, structures and properties of metal phosphonates based on m-xylylenediphosphonic acid

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Chinese Science Bulletin 2014年第34期59卷 4720-4727页

作者： Yu yang Wei Xu yuanxin Li Meng Liu Yiheng Zhang Lei Wang Key Laboratory of Eco-chemical Engineering Ministry of Education College of Chemistry and Molecular EngineeringQingdao University of Science and Technology

In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids(H4L), including[M(H2L)(bpy)](M = Mn 1, Co 2), [MH2L)(phen)](M = Co3, Cu 4), and [Cu2(H2L)2(bpy00)2] 5(bpy = 2,20-bipyridine,phen = 1,10-phenanthroline, bpy00= 4,40-dimethyl-2,20-bipyridine). X-ray diffraction indicated that compounds 1 and2 were isomorphic. Complexes 3 and 4 were shown to crystallize in different space groups but had similar crystallographic units. In the complexes, H4 L was seen to partially deprotonate to afford H2L2-. The H2L2-ligands in 1–4functioned as tetradentate ligands with each phosphonate group adopting bidentate coordination mode with two M centers to generate a 2D layer. In addition, the H2L2-anions in5 functioned as tridentate ligands with one phosphonate group adopting the bidentate mode and another phosphonate group adopti ng the monodentate mode, thus linking three Cu atoms to provide a 1D chain. The IR and thermal stabilities of these compounds were subsequently examined.

关键词：水热合成结构表征膦酸盐金属特性联吡啶 H2L 双齿配位

海绵城市建设对住房价格影响的定量分析——以四川省遂宁市为例

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清华大学学报（自然科学版） 2021年第6期61卷 573-581页

作者：沈阳徐苑昕吴璟清华大学建设管理系恒隆房地产研究中心北京100084

海绵城市是中国近年来城市建设与更新中被大力倡导的新概念,能够提高生态建设水平、缓解城市洪涝灾害问题和促进水的循环利用。海绵城市建设带来了人居环境的提升,提高了人们对住宅的支付意愿。该文以四川省遂宁市为例,定量分析了海绵... 详细信息

海绵城市是中国近年来城市建设与更新中被大力倡导的新概念,能够提高生态建设水平、缓解城市洪涝灾害问题和促进水的循环利用。海绵城市建设带来了人居环境的提升,提高了人们对住宅的支付意愿。该文以四川省遂宁市为例,定量分析了海绵城市建设对住房市场价格的影响。分析结果显示:建设海绵设施会使小区房价上涨年均385.2元/m^(2)(即5.48%);溢价出现的时点与遂宁市雨季出现时间一致;遂宁市通过建设海绵城市在房地产市场溢价方面带来的总经济效益为39.85亿元,考虑各方面贡献后整体效益为63.02亿元,超过了建设成本。

关键词：海绵城市成本效益分析住房溢价

Cascade adsorptive separation of light hydrocarbons by commercial zeolites

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Journal of Energy Chemistry 2022年第9期31卷 299-305,I0009页

作者： Shanshan Liu Yinlin Chen Bin Yue yuanxin Nie Yuchao Chai Guangjun Wu Jiangnan Li Xue Han Sarah JDay Stephen PThompson Naijia Guan Sihai yang Landong Li School of Materials Science and Engineering Nankai UniversityTianjin 300350China Department of Chemistry The University of ManchesterManchester M139PLUnited Kingdom Diamond Light Source Harwell Science CampusOxfordshire OX110DEUnited Kingdom Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Adsorptive separation of light hydrocarbons by porous solids provides an energy-efficient alternative to state-of-the-art cryogenic distillation.However,an optimal balance between the cost,performance and stability of the sorbent material is yet to be achieved for industrial applications.Here,we report the efficient separation of C2 and C3 hydrocarbons by a faujasite zeolite(Na-X,Si/Al=1.23).A tandem configuration of two fixed-beds packed with Na-X affords complete dynamic separation of the ternary mixture of C_(2)H_(2)/C_(2)H_(4)/C_(2)H_(6)(1/49.5/49.5;v/v/v)under ambient conditions.Pressure-swing desorption on the latter fixed-bed gives ethylene(>99.50%,1.80 mmol g^(-1))and ethane(>99.99%,1.41 mmol g^(-1)).In situ synchrotron X-ray powder diffraction revealed the binding sites for C_(2)H_(2)and C_(2)H_(4)in Na-X.This study highlights the potential application of commercial zeolites for challenging industrial separations.

关键词： Zeolites C2 hydrocarbons Ethylene Adsorptive separation

基于改进ESO的四旋翼姿态自抗扰控制器设计

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系统工程与电子技术 2022年第12期44卷 3792-3799页

作者：杨文奇卢建华姜旭王元鑫海军航空大学航空基础学院山东烟台264000 海军航空大学青岛校区山东青岛266000

针对四旋翼无人机姿态自抗扰控制(active disturbance rejection control,ADRC)系统在姿态角测量反馈信号受传感器噪声污染时,基于传统非线性非光滑fal函数的扩张状态观测器(extended state observer,ESO)观测精度不足的问题,构建了一... 详细信息

针对四旋翼无人机姿态自抗扰控制(active disturbance rejection control,ADRC)系统在姿态角测量反馈信号受传感器噪声污染时,基于传统非线性非光滑fal函数的扩张状态观测器(extended state observer,ESO)观测精度不足的问题,构建了一种新型非线性光滑galn函数以重新设计ESO,并利用Matlab/Simulink仿真软件进行性能验证。仿真结果表明:与传统fal函数相比,本文构建的galn函数为光滑且具有更好的收敛性,更能体现“大误差小增益”的工程思想;基于galn函数设计的改进型ESO具有更强的误差跟随能力;采用改进型ESO设计的四旋翼姿态ADRC系统具有更好的跟踪能力和抗干扰能力。

关键词：四旋翼无人机扩张状态观测器自抗扰控制 galn函数

Connecting past and present:single-cell lineage tracing

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Protein & Cell 2022年第11期13卷 790-807页

作者： Cheng Chen yuanxin Liao Guangdun Peng Center for Cell Lineage and Development CAS Key Laboratory of Regenerative BiologyGuangdong Provincial Key Laboratory of Stem Cell and Regenerative MedicineGIBH-HKU Guangdong-Hong Kong Stem Cell and Regenerative Medicine Research CentreGuangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhou 510530China Center for Cell Lineage and Atlas Bioland Laboratory(Guangzhou Regenerative Medicine and Health Guangdong Laboratory)Guangzhou 510005China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Central to the core principle of cell theory,depicting cells'history,state and fate is a fundamental goal in modern biology.By leveraging clonal analysis and sin-gle-cell RNA-seq technologies,single-cell lineage trac-ing provides new opportunities to interrogate both cell states and lineage histories.During the past few years,many strategies to achieve lineage tracing at single-cell resolution have been developed,and three of them(in-tegration barcodes,polylox barcodes,and CRISPR barcodes)are noteworthy as they are amenable in experimentally tractable systems.Although the above strategies have been demonstrated in animal develop-ment and stem cell research,much care and effort are still required to implement these methods.Here we review the development of single-cell lineage tracing,major characteristics of the cell barcoding strategies,applications,as well as technical considerations and limitations,providing a guide to choose or improve the single-cell barcoding lineage tracing.

关键词： single-cell lineage tracing integration barcodes polylox barcodes CRISPR barcodes

Aromatic Carbon Coated Tin Composites as Anode Materials for Lithium Ion Batteries

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Wuhan University Journal of Natural Sciences 2013年第3期18卷 191-194页

作者： AI Changchun HU Yi LIU yang SUN Jutang TIAN Qifeng WU yuanxin Hubei Research and Design Institute of Chemical Industry Wuhan Institute of Technology School of Chemical Engineering and Pharmacy Wuhan Institute of Technology College of Chemistry and Molecular Science Wuhan University

Aromatic carbon coated tin composites（A/Sn） have been prepared by thermal decomposition of the stannous 1,8-naphthalenedicarboxylate precursors,which is a reformative preparation method.Sugar carbon coated tin composites（S/Sn） also are prepared as a contrast with the A/Sn composites.The morphology and composition of the products were characterized by Scanning Electricity Microscopy（SEM） and X-Ray Diffraction（XRD）.Their electrochemical performance as anode materials for lithium ion batteries were investigated;the results indicated that these materials exhibited good performance,and the cycle stability of A/Sn composites is especially superior to the S/Sn composites due to its special carbon resource.

关键词： aromatic carbon coated tin composites thermal decomposition anode materials lithium-ion batteries

A Unifiedspatio-temporal Descrption Model of Environment for Intelligent Vehicles

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A Unifiedspatio-temporal Descrption Model of Environment for...