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Big Earth Data 2022年第1期6卷 77-89页

作者： Jinhu Bian Ainong Li Xi Nan Guangbin Lei Zhengjian Zhang Research Center for Digital Mountain and Remote Sensing Application Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengduChina

Mountains are undergoing widespread changes caused by human activities and climate change.Given the importance of mountains,the protection and sustainable development of mountain ecosys-tems have been listed as the goals of the United Nations 2030 Sustainable Development Agenda.As one of the indicators,the Mountain Green Cover Index(MGCI)datasets can provide consis-tent and comparable status of green vegetation in mountainous areas,which can support the mapping of heterogeneous mountain ecosystem health and monitoring changes over time.The produc-tion of explicitly high-spatial-resolution MGCI datasets is therefore urgently needed to support the protection measures at subnational and multitemporal scales.In this paper,the MGCI datasets with 500-meter spatial resolutions,covering the economic corridors of the Belt and Road Initiative(BRI),were developed for 2010 to 2019 based on all available Landsat-8 data and the Google Earth Engine cloud computing platform.The validation of green vegeta-tion cover with the ground-truth samples indicated that the data-sets can achieve an overall accuracy of 94.06%,with well-detailed spatial and temporal variations.The archived datasets include the MGCI of each BRI economic corridor,matched to a geospatial layer denoting the economic corridor boundaries.The essential informa-tion of the datasets and their limitations,along with the production flow,were described in this paper.

关键词： Sustainable development goals(SDGs) mountain green cover index(MGCI) dataset Belt and Road Landsat

A review of land use/land cover change mapping in the China-Central Asia-West Asia economic corridor countries

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Big Earth Data 2021年第2期5卷 237-257页

作者： Amin Naboureh Jinhu Bian Guangbin Lei Ainong Li Research Center for Digital Mountain and Remote Sensing Application Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengduChina University of Chinese Academy of Sciences BeijingChina

Large-scale projects,such as the construction of railways and highways,usually cause an extensive Land Use Land Cover Change(LULCC).The China-Central Asia-West Asia Economic Corridor(CCAWAEC),one key large-scale project of the Belt and Road Initiative(BRI),covers a region that is home to more than 1.6 billion people.Although numerous studies have been conducted on strategies and the economic potential of the Economic Corridor,reviewing LULCC mapping studies in this area has not been studied.This study provides a comprehensive review of the recent research progress and discusses the challenges in LULCC monitoring and driving factors identifying in the study area.The review will be helpful for the decision-making of sustainable development and construction in the Economic Corridor.To this end,350 peer-reviewed journal and conference papers,as well as book chapters were analyzed based on 17 attributes,such as main driving factors of LULCC,data collection methods,classification algorithms,and accuracy assessment methods.It was observed that:(1)rapid urbanization,industrialization,population growth,and climate change have been recognized as major causes of LULCC in the study area;(2)LULCC has,directly and indirectly,caused several environmental issues,such as biodiversity loss,air pollution,water pollution,desertification,and land degradation;(3)there is a lack of well-annotated national land use data in the region;(4)there is a lack of reliable training and reference datasets to accurately study the long-term LULCC in most parts of the study area;and(5)several technical issues still require more attention from the scientific community.Finally,several recommendations were proposed to address the identified issues.

关键词： Land use change land cover change China-Central Asia-West Asia Economic Corridor accuracy assessment reference data classification algorithm

Solid-state preparation of mesoporous Ce-Mn-Co ternary mixed oxide nanoparticles for catalytic degradation of methylene blue

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Journal of Rare Earths 2021年第7期39卷 826-834,I0003页

作者： Qingwen Wang Wenyong Deng Xinchen Lin Xigen Huang Ling Wei lei Gong Changxiang Liu guangbin Liu Qian Liu Key Laboratory of Chemical Utilization of Plant Resources of Nanchang College of ScienceJiangxi Agricultural UniversityNanchang 330045China

Mesoporous Ce-Mn-Co ternary metal oxide was fabricated via an efficient oxalate-precursor-based soft reactive grinding route and used to activate H_(2)O_(2) for advanced oxidation of methylene blue in water.In addition,Mn-Co binary oxide and pure Co_(3)O_(4) and Mn_(3)O_(4) were also synthesized as reference catalysts.These catalysts were characterized by X-ray diffraction,N_(2) adsorption-desorption,H_(2)-temperature programmed reduction,transmission electron microscopy,scanning electron microscopy and X-ray photoelectron spectroscopy.The results demonstrate that part of the Ce and Mn can be incorporated into the lattice of Co_(3)O_(4) and cause severe lattice distortion of the unit cell.Compared with the single or binary system,Ce-Mn-Co ternary metal oxide exhibits the best activity in methylene blue removal and nearly 100% decomposition rate and 84% COD removal rate can be achieved in 12 h,and with degradation rate of 93.5% after three rounds.These results are primarily attributed to the synergistic effect of Ce,Mn and Co,which can promote the formation of more lattice defects,higher specific surface area and smaller particle size.Quenching tests show that hydroxyl radicals(·OH) play more dominant role than superoxide radicals(·O_(2)^(-)).Kinetic studies were studied and the activation energies of all the catalysts were calculated.

关键词： Ce-Mn-Co mixed Oxide Methylene blue Advanced oxidation processes Soft reactive grinding Rare earths

Study on the mechanism of rapid formation ofu ultra-thick tribofilm by CeO_(2)nano additive and ZDDP

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Friction 2023年第1期11卷 48-63页

作者： Xue lei Yujuan ZHANG Shengmao ZHANG guangbin YANG Chunli ZHANG Pingyu ZHANG National&Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004China

CeO_(2)nanoparticles are potential anti-wear additives because of their outstanding anti-wear and load-bearing capacity.However,the shear-sintering tribo-film formation mechanism of oxide nanoparticles limits the tribo-film formation rate and thickness greatly.In this study,by compounding with zinc dioctyl dithiophosphate(ZDDP),ultra-fine CeO_(2)nanoparticles modified with oleylamine(OM)can quickly form 2μm ultra-thick tribo-film,which is 10-15 times thicker than that of ZDDP and CeO_(2),respectively.The ultra-thick tribo-film presents a nanocomposite structure with amorphous phosphate as binder and nano-CeO_(2)as filling phase,which leads to the highest loading capacity of composite additives.The results of adsorption experiments tested by dissipative quartz crystal microbalance(QCM-D)showed that the Ps value of additive has nothing to do with its equilibrium adsorption mass,but is directly proportional to its adsorption rate in 10 s.The compound additive of CeO_(2)and ZDDP presented the co-deposition mode of ZDDP monolayer rigid adsorption and CeO_(2)viscoelastic adsorption on the metal surface,which showed the highest adsorption rate in 10 s.It is found that the tribo-film must have high film forming rate and wear resistance at the same time in order to achieve super thickness.Cerium phosphate was formed from ZDDP and CeO,through tribochemistry reaction,which promotes the formation of an ultra-thick tribo-film with nanocomposite structure,which not only maintains the low friction characteristics of CeO,but also realizes high Pg and high load-carrying capacity.

关键词： CeO_(2)nanoadditives adsorption nanocomposite ultra-thick tribofilm zinc dioctyl dithiophosphate(7DDP)

Exploring the High-efficiency Clash Detection between Architecture and Structure 3rd

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Exploring the High-efficiency Clash Detection between Archit...

四川省汉源地区苏雄组火山岩地球化学特征及其对铀成矿作用的启示

2011 International Conference on Information Management and Engineering(ICIME 2011)

作者： Wang guangbin lei Wei Duan Xuru School of Economics and Management Tongji University

ISBN: (纸本)9781612842387

Building Information Modeling (BIM) has recently attained widespread attention in the AEC/FM (Architectural, Engineering and Construction/Facilities Management) industry. However, the adoption of BIM is under expectation. Clash detection is critical for adopting BIM, because it is the main part to use for calculating for ROI (return of investment). At the same time, efficiency problem arises in the course of the practical application of clash detection: While existing commercial clash detection software can provides an army of clashes, yet it still need handwork to distinguish design errors from modeling errors. To improve this low-efficiency process, This research provide a revised work process utilizing space naming and coding based on Product Breakdown Structure(PBS), then introduces a case of Shanghai West Railway Station in P.R.China to text this revised process.

关键词： Adoption of information technology in organizations, Object-oriented enterprise modeling, Building Information Model, model checking clash detection, return on investment, Product Breakdown Structure, information technology

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矿物岩石 2023年第3期43卷 48-59页

作者：阚磊徐争启田建民吴广彬成都理工大学地球科学学院四川成都610059 地球勘探与信息技术教育部重点实验室四川成都610059 地学核技术四川省重点实验室四川成都610059

为了解扬子陆块西缘铀成矿与苏雄组火山岩年代学特征、构造环境之间的关系,初步建立铀富集机理,对扬子陆块西缘的铀富集与成矿提供新的理论依据,本次研究在结合前人研究的基础上,对汉源地区苏雄组火山岩的元素地球化学特征、锆石U-Pb测... 详细信息

为了解扬子陆块西缘铀成矿与苏雄组火山岩年代学特征、构造环境之间的关系,初步建立铀富集机理,对扬子陆块西缘的铀富集与成矿提供新的理论依据,本次研究在结合前人研究的基础上,对汉源地区苏雄组火山岩的元素地球化学特征、锆石U-Pb测年及Lu-Hf同位素进行分析,苏雄组酸性火山岩富硅(SiO_(2)=66.27%~77.02%)、富钾(K_(2)O=2.72%~7.29%)、富铝(Al_(2)O_(3)=11.65%~18.84%),属钙碱性-碱性系列岩石;A/NK为1.43~3.12,A/CNK为1.36~3.01,属强过铝质。岩石相对富集Rb, Th, U,La, Ce,而相对亏损Ba, Nb, Ta, Ti,具有较高的稀土总量(ΣREE=196.83×10^(-6)~2 062.21×10^(-6)),相对富集轻稀土,亏损重稀土,轻重稀土分异明显((La/Yb)N比值为4.10~13.63),具有明显的Eu负异常(δEu=0.27~1.60)。样品具有相对高的10 000 Ga/Al值,锆石饱和温度908~1 003℃,指示其具有A2型花岗岩的地球化学特征。定年结果显示苏雄组酸性火山岩形成于新元古代中期为809.0±6.6 Ma, εHf(t)值为0.5~3.3,平均1.82,TDM1=1 266~1 337 Ma,平均1 303 Ma,为中元古代。苏雄组火山岩来源为中元古代的新增生中基性下地壳部分熔融并有幔源组分加入,形成于俯冲大背景下的弧后伸展环境,表明了扬子陆块西缘俯冲环境的阶段性和复杂性,洋壳的俯冲后退造成富Na软流圈的上涌为铀的富集提供了萃取剂和热点,表明了840~780 Ma弧后发展至弧前的扬子陆块西缘具有一定的铀成矿潜力。

关键词：苏雄组火山岩构造环境汉源地区铀富集与成矿弧后伸展环境

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低维Bi_2Te_3基热电材料的研究进展

材料导报 2009年第21期23卷 34-37页

作者：郭磊姬广斌南京航空航天大学材料科学与技术学院南京210016 南京大学物理系南京210093

Bi2Te3及其固溶体合金是目前室温附近发展最为成熟、性能最好的一类热电材料,在热电制冷及温差发电方面具有广阔的应用前景。如何最大限度地提高材料的热电优值是当今热电材料研究的主要问题。传统块体Bi2Te3基热电材料的最高ZT值只能达... 详细信息

Bi2Te3及其固溶体合金是目前室温附近发展最为成熟、性能最好的一类热电材料,在热电制冷及温差发电方面具有广阔的应用前景。如何最大限度地提高材料的热电优值是当今热电材料研究的主要问题。传统块体Bi2Te3基热电材料的最高ZT值只能达到1.0左右,而低维化、纳米化的Bi2Te3基热电材料可使电子和声子的传输得到合理调控,从而大幅提升材料的热电性能。综述了二维纳米薄膜、一维纳米线(管、棒)和准零维纳米颗粒等低维Bi2Te3基热电材料的最新研究进展,并结合目前的研究状况展望了今后的研究重点及发展方向。

关键词： Bi2Te3 低维化热电性能

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假性动脉瘤破裂死亡患者临床及影像特征

中国医学影像学杂志 2024年第5期32卷 499-503,509页

作者：安攀井勇李飞崔光彬雷学斌空军军医大学第二附属医院放射科陕西西安710038

目的探讨假性动脉瘤破裂死亡病例的临床特点和影像学特征,加强认知,提高预防策略和早期诊治意识。资料与方法回顾性分析2016年1月—2021年12月空军军医大学第二附属医院6例假性动脉瘤破裂死亡患者的临床、CT及MRI资料。结果假性动脉瘤CT... 详细信息

目的探讨假性动脉瘤破裂死亡病例的临床特点和影像学特征,加强认知,提高预防策略和早期诊治意识。资料与方法回顾性分析2016年1月—2021年12月空军军医大学第二附属医院6例假性动脉瘤破裂死亡患者的临床、CT及MRI资料。结果假性动脉瘤CT及MRI表现为突出载瘤动脉的类圆形或不规则形瘤体,并可见破口与载瘤动脉相通,瘤体内可有血栓形成,邻近载瘤动脉可有受压移位、管腔变细或增粗等表现。影像学检查提示6例假性动脉瘤位置、形态、大小、破口大小、与载瘤动脉的关系以及与周围组织结构的关系显示清晰,诊断明确。2例均因误吞枣核、内镜下取出后主动脉弓部假性动脉瘤形成,病1例外伤、1例介入术后导致假性动脉瘤形成,1例病因不明,1例因颅内非特异性感染侵蚀邻近血管壁导致左侧颈内动脉海绵窦段假性动脉瘤形成。6例病例死亡前均有突发呕血或鼻出血症状,提示假性动脉瘤破裂。结论假性动脉瘤破裂死亡率高,CT及MRI可客观显示其影像学特征,具有一定的临床价值。

关键词：动脉瘤,假性主动脉体层摄影术,X线计算机磁共振成像

青藏高原东南缘气象要素Anusplin和Cokriging空间插值对比分析

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高原气象 2016年第4期35卷 875-886页

作者：谭剑波李爱农雷光斌中国科学院成都山地灾害与环境研究所成都610041 中国科学院大学北京100049

选取地形起伏度巨大的青藏高原东南缘为研究区,利用该研究区96个气象站点,结合高程数据,分别采用Cokriging和Anusplin空间插值方法,获取2010年250 m分辨率的年均温度和年累计降水插值曲面。并采用交叉验证方法对比Anusplin与Cokriging... 详细信息

选取地形起伏度巨大的青藏高原东南缘为研究区,利用该研究区96个气象站点,结合高程数据,分别采用Cokriging和Anusplin空间插值方法,获取2010年250 m分辨率的年均温度和年累计降水插值曲面。并采用交叉验证方法对比Anusplin与Cokriging插值精度,分析了误差的空间分布特征,重点对比两种插值曲面差异较大的区域精度优劣,评价两种方法在复杂地区的适用性。结果表明,Anusplin在复杂地表的插值表现优于Cokriging,其中Anusplin气温插值的均方差仅为0.82℃,而Cokriging的均方差为1.45℃;两者的降水插值精度基本一致,但Anusplin在气象要素空间异质性大的区域优于Cokriging。因此,与Cokriging相比,Anusplin更适合青藏高原东南缘复杂地表气象要素空间插值。

关键词：青藏高原东南缘空间插值年均温年累计降水 Anusplin Cokriging

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GPS伪随机序列的构成与应用分析

光通信研究 2010年第6期 64-67页

作者：雷雄俊刘光斌第二炮兵工程学院陕西西安710025

文章分析了全球定位系统(GPS)信号中3个频段上民用伪随机码的基本特征,包括码的生成结构、调制方式、数据构成和信号能量;结合L1上粗捕获(C/A)码的特征,讨论了GPS现代化信号(L2和L5)上民用伪随机码的改进,重点分析了数据通道和无数据通... 详细信息

文章分析了全球定位系统(GPS)信号中3个频段上民用伪随机码的基本特征,包括码的生成结构、调制方式、数据构成和信号能量;结合L1上粗捕获(C/A)码的特征,讨论了GPS现代化信号(L2和L5)上民用伪随机码的改进,重点分析了数据通道和无数据通道的优势和区别以及L5上Neumann-Hoffman(NH)码的作用,定性分析了新型的伪随机码的组成和调制方式对GPS信号捕获和抗干扰性能的影响。

关键词：伪随机序列全球定位系统无数据通道 NH码