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基于航磁资料的中国蛇绿岩带研究

地质学报 2024年第3期98卷 725-757页

作者：熊盛青杨海范振宇刘福香中国自然资源航空物探遥感中心北京100083 自然资源部航空地球物理与遥感地质重点实验室北京100083 自然资源部深地科学与探测技术实验室北京100094 中国地质大学(北京) 北京100083

通过六十多年的积累,我国已经基本完成了中国陆域的航磁覆盖,为区域地质构造研究提供了详实的地球物理资料。航磁异常主要反映了岩石圈中磁性物质的分布情况,尤其是构造-岩浆活动能够产生明显的磁异常,为隐伏岩浆岩的预测研究奠定了基... 详细信息

通过六十多年的积累,我国已经基本完成了中国陆域的航磁覆盖,为区域地质构造研究提供了详实的地球物理资料。航磁异常主要反映了岩石圈中磁性物质的分布情况,尤其是构造-岩浆活动能够产生明显的磁异常,为隐伏岩浆岩的预测研究奠定了基础。镁铁—超镁铁质岩通常具有较强的磁性,可以通过航磁异常进行识别。本文基于全国1:100万航磁数据及其岩性-构造解释结果,阐述了通过航磁异常识别镁铁—超镁铁质岩的标志和圈定方法,分析了推断镁铁—超镁铁质岩与蛇绿岩带的关系。研究表明,蛇绿岩带通常都具有形态规则、宽度窄、异常幅值大的线性或串珠状磁异常特征,主要与蛇绿岩的保存情况密切相关。蛇绿岩带通常是不同板块的拼接带,呈现出区域磁异常边界的特征,代表不同陆块的基底性质的差异。但是,部分蛇绿岩带,如弧后盆地拉张等形成的蛇绿岩,因两侧地块基底性质相似,通常不具有分割区域磁场的特点。基于航磁推断镁铁—超镁铁质岩分布,在全国划分了22个蛇绿岩型镁铁—超镁铁质岩带,并对岩带的特征进行了详细描述。例如,雅鲁藏布江蛇绿岩带呈现出双磁异常带的特征,北带磁异常的规模较大、延伸长,推断深部存在镁铁—超镁铁质岩。南带磁异常规模较小,仅在日喀则地区连续分布,其余为串珠状磁异常,且不具有分割区域磁场的特点。通过磁异常三维反演,构建了雅鲁藏布江蛇绿岩带的深部结构模型。本文旨在通过磁异常的定性和定量分析,为蛇绿岩带(缝合带)的研究提供更多的信息,尤其是隐伏蛇绿岩,以指导铬铁矿找矿。目前航磁测量以中小比例尺为主,对于蛇绿岩带研究及铬铁矿找矿勘查是不足的,精细的分析和深部结构建模需要1:5万或更大比例尺航磁数据。

关键词：航磁异常镁铁—超镁铁质岩蛇绿岩深部结构铬铁矿

催化剂加氢能力对减压渣油中沥青质组成与结构的影响

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化学工业与工程 2024年第3期41卷 1-10页

作者：蔺聪福田磊郭强杨勇冯富祥刘源天津大学化工学院天津300350 中科合成油技术股份有限公司国家能源煤基液体燃料研发中心北京101407 中科合成油内蒙古有限公司内蒙古鄂尔多斯010300

考察了氧化硅担载铁硫催化剂在浆态床反应器中对Merey减压渣油的转化性能。采用元素分析、GPC、XPS、1H-NMR、FT-IR和XRD等手段研究加氢催化剂对Merey减压渣油中沥青质组成与结构转变的影响,并分析加氢催化剂抑制沥青质生焦转化影响机... 详细信息

考察了氧化硅担载铁硫催化剂在浆态床反应器中对Merey减压渣油的转化性能。采用元素分析、GPC、XPS、1H-NMR、FT-IR和XRD等手段研究加氢催化剂对Merey减压渣油中沥青质组成与结构转变的影响,并分析加氢催化剂抑制沥青质生焦转化影响机制。结果表明,随着催化剂加氢能力增强,沥青质组成中w(N)和w(S)不断降低,最容易发生加氢脱硫反应,n(H)/n(C)、平均链长(n)与缩合度参数(HAU/CA)升高,芳香度(fA)、堆叠芳香片层的平均高度(Lc)、芳香片层直径(La)与堆叠芳香片层的平均数量(M)下降。这主要是由于加氢能力强的催化剂可以提供较多氢自由基,使沥青质结构中稠合芳环加氢,以产生较长侧链,长侧链阻碍沥青质形成较大尺寸的纳米聚集体,进而抑制沥青质从油相中析出转化为焦炭。

关键词：沥青质加氢转化浆态床

Novel infrared and visible image fusion method based on independent component analysis

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Frontiers of Computer Science 2014年第2期8卷 243-254页

作者： Yin LU fuxiang WANG Xiaoyan LUO Feng liu National Key Laboratory of CNS/ATM School of Electronics and Information Engineering Beihang University Beijing 100191 China

The goal of infrared （IR） and visible image fu- sion is for the fused image to contain IR object features from the IR image and retain the visual details provided by the visible image. The disadvantage of traditional fusion method based on independent component analysis （ICA） is that the primary feature information that describes the IR objects and the secondary feature information in the IR image are fused into the fused image. Secondary feature information can de- press the visual effect of the fused image. A novel ICA-based IR and visible image fusion scheme is proposed in this paper. ICA is employed to extract features from the infrared image, and then the primary and secondary features are distinguished by the kurtosis information of the ICA base coefficients. The secondary features of the IR image are discarded during fu- sion. The fused image is obtained by fusing primary features into the visible image. Experimental results show that the pro- posed method can provide better perception effect.

关键词： image fusion independent component analysis(ICA) feature extraction kurtosis

Species,engineering and characterizations of defects in TiO2-basedphotocatalyst

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Chinese Chemical Letters 2018年第5期29卷 671-680页

作者： Beibei Dong Taifeng liu Can Li fuxiang Zhang State Key Laboratory of Catalysis 2011-iChEM Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Dalian 116023 China university of Chinese Academy of Sciences Beijing 100049 China National & Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Collaborative Innovation Center of Nano FunctionalMaterials and Applications of Henan Province Henan University Kaifeng 475004 China

Light absorption, charge separation and surface reaction are considered as the main processes ofphotocatalysis on one semiconductor, and all of them are demonstrated to be related to the defect statesof photocatalysts. This paper will choose Ti02 as model photocatalyst to introduce some basic conceptsand strategies related to defects and methods developed to characterize defects in the past ***, such strategies as hydrogenation and metal/nonmetal doping intoTi02 will be introduced toextend utilization of solar spectrum and/or to provide active sites. On the contrary, the unfavorable effectof defects such as acting as recombination centers of photogenerated carriers will also be *** typical methods to characterize the properties of defects are summarized, which contain electronparamagnetic resonance （EPR）, photoluminescence technique （PL）, positron annihilation spectroscopy（PAS）, and so on. We do hope that this review will make a revealing effect on understanding to thefunctions of defects as well as construction of efficient photocatalytic systems in the future.

关键词： Titanium dioxide Defect engineering Photocatalysis Water splitting Environmental purification

Matrix calculation of high-dimensional cross product and its application in automatic recognition of the endmembers of hyperspectral imagary

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Science China(Information Sciences) 2011年第1期54卷 197-203页

作者： GENG XiuRui1,ZHAO YongChao1,liu SuHong2 & WANG fuxiang3 1Key Laboratory of Technology in Geo-spatial Information Processing and Application System, Institute of Electronics,Chinese Academy of Sciences,beijing 100080,China 2State Key Laboratory of Remote Sensing Science,Jointly Sponsored by beijing Normal university and the Institute of Remote Sensing Applications of Chinese Academy of Sciences, School of Geography,beijing Normal university,beijing 100875,China 3School of Electronics and Information Engineering,Beihang university,beijing 100191,China Key Laboratory of Technology in Geo-spatial Information Processing and Application System Institute of Electronics Chinese Academy of Sciences Beijing China State Key Laboratory of Remote Sensing Science Jointly Sponsored by beijing Normal university and the Institute of Remote Sensing Applications of Chinese Academy of Sciences School of Geography Beijing Normal University Beijing China School of Electronics and Information Engineering Beihang University Beijing China

This paper gives the definition of the high-dimensional cross product and its calculation by extending the 3-D cross product definition into the high-dimensional vector *** on the properties of the cross product,the volume variance index(VVI)is proposed to be used in extracting automatically the endmembers of the hypherspectral imagery which eliminates the shortcoming of the traditional method of using simplex only where the extraction results were easily impacted by the abnormal pixels.A case study of endmembers extraction experiment using the VVI method with the AVIRIS data for Cuprite has shown a very good result.

关键词： endmember simplex hyperspectral imagery cross product

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广东省水稻孢囊线虫病调查与鉴定

中国水稻科学 2024年第4期38卷 456-462页

作者：刘福祥甄浩洋彭焕郑刘春彭德良文艳华华南农业大学植物保护学院广东510642 中国农业科学院植物保护研究所植物病虫害生物学国家重点实验室北京100193

【目的】明确广东省水稻上孢囊线虫发生种类、分布。【方法】从广东省的14个市采集了231份水稻根系和根际土壤样品,从水稻根系及根际土壤样品中分离孢囊线虫,采用形态学和分子生物学方法鉴定孢囊线虫种类。【结果】在广东清远、肇庆、... 详细信息

【目的】明确广东省水稻上孢囊线虫发生种类、分布。【方法】从广东省的14个市采集了231份水稻根系和根际土壤样品,从水稻根系及根际土壤样品中分离孢囊线虫,采用形态学和分子生物学方法鉴定孢囊线虫种类。【结果】在广东清远、肇庆、江门等地水稻根系及根际土样中发现孢囊线虫,孢囊检出率分别为40%、23.7%、10%。形态学研究表明,孢囊柠檬形或近圆形,主要为柠檬形,阴门锥双半膜孔,膜孔近圆形,阴门桥窄,下桥中等大小;二龄幼虫唇区半球形,略缢缩;尾圆锥形,尾端尖,透明尾长占尾长的53%~66%。分子生物学研究表明,该线虫28S rDNA D2-D3区序列与NCBI数据库中旱稻孢囊线虫相似度99.73%~100%,rDNA-ITS区序列与NCBI数据库中旱稻孢囊线虫相似度96.72%~99.91%。系统进化树分析表明,该线虫与旱稻孢囊线虫处于同一分支,置信度为100%。使用旱稻孢囊线虫特异性引物he-F/he-R扩增清远、肇庆、江门采集的孢囊线虫rDNA-ITS区均得到281 bp的单一条带,与已报道结果一致。【结论】清远、肇庆、江门采集到的孢囊线虫均为旱稻孢囊线虫。这是首次在广东省发现旱稻孢囊线虫。

关键词：旱稻孢囊线虫水稻发生分布种类鉴定

One dimensional nickel phosphide polymorphic heterostructure as carbon-free functional support loading single-atom iridium for promoted electrocatalytic water oxidation

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Journal of Energy Chemistry 2023年第4期79卷 410-417页

作者： Rashid Mehmood Guifa Long Wenjun Fan Mingrun Li Lifang liu fuxiang Zhang StateKey Laboratory of Catalysis iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyDalian 116023LiaoningChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China GuangxiKey Laboratory of Chemistry and Engineering of Forest Products School of Chemistry and Chemical EngineeringGuangxi Minzu UniversityNanning 530008GuangxiChina

Although conducting materials such as carbon nanotube and carbon fiber paper(CFP)have been extensively employed as support of electrocatalytic active sites,most of them are of poor catalytic functionality by themselves and undesirable stability during strong acid/alkaline environments or oxidation *** we report a novel one-dimensional(1D)nickel phosphide polymorphic heterostructure(denoted as NPPH)to work as one effective carbon-free functional support for loading of single-atom Ir water oxidation ***,the NPPH composed of both Ni12P5and Ni2P phases is not only active for robust alkaline water oxidation but also is of good stability and hydrophilicity for favorable loading of single-atom dispersed *** NPPH supported single-atom Ir electrocatalyst(Ir/NPPH)is found to exhibit remarkably superior water oxidation activity with respect to the NPPH itself or CFP supported single-atom Ir catalyst(Ir/CFP),demonstrating the synergetic promotion effect between NPPH and single-atom Ir ***,the NPPH supported single-atom Ir catalyst can bear alkaline water oxidation for over 120 h at current density of 50 mA cm^(-2).The NPPH developed here is expected as functional support to composite with other water oxidation catalysts,as may be an alternative strategy of developing highly efficient carbon-free electrocatalysts.

关键词： Oxygen evolution reaction Single atom catalyst Nickel phosphide heterostructure One-dimensional

Operation of the CSNS Penning surface H^- ion source

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 245-248页

作者： WU XiaoBing OUYANG HuaFu CHI YunLong he Wei HUANG Tao LI Gang liu YingMan LU YanHua XU TaoGuang ZHANG JunSong ZHANG HuaShun ZHAO fuxiang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Graduate university of Chinese Academy of Sciences Beijing 100049China

The accelerator complex of the China Spallation Neutron Source (CSNS) consists of a H- linear accelerator (linac) and a rapid cycling synchrotron (RCS). The linac contains a Penning surface H- ion source. The designed energy and the beam current of the source are 50 keV and 20 mA respectively, with a normalized root mean square (norm. rms.) emittance of 0.2π mm mrad. The manufactures and tests of the discharge chamber are in great progress. The construction of H- ion source test stand has been completed, and the operation of the source is also in progress. Stable H- ion beams with energy of 50 keV and current up to 50 mA are attained. Emittance measurement for the H- beam is being prepared.

关键词： CSNS Penning H- ion source discharge chamber current emittance

Water-stable Mn-based MOF nanosheet as robust visible-light-responsive photocatalyst in aqueous solution

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Science China Chemistry 2020年第12期63卷 1756-1760页

作者： Yejun Xiao Xiangyang Guo Tongtong Yang Junxue liu Xuan liu Yu Xiao Lifang liu Taifeng liu Sheng Ye Jun Jiang fuxiang Zhang Can Li State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energythe Collaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China hefei National Laboratory for Physical Sciences at the Microscale CAS Center for Excellence in NanoscienceSchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of Molecular Reaction Dynamics the Collaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalin 116023China university of Chinese Academy of Sciences Beijing 100049China National&Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Collaborative Innovation Center of Nano Functional Materials and Applications of Henan ProvinceHenan UniversityKaifeng 475000China

Development of visible-light-responsive metal-organic frameworks(MOFs) for promising solar energy conversion has inspired continuous interest, but it still suffers from poor stability especially in aqueous solution and/or under photoirradiation due to their relatively labile coordination bonds. herein, a new synthesized layered Mn-based MOF(Mn-TBAPy-BK) and its exfoliated twodemensional nanosheets(Mn-TBAPy-NS) are revealed to be highly stable no matter in aqueous solution with wide p H region or under visible light irradiation. As expected, the exfoliated Mn-TBAPy-NS exhibits enhanced surface area, shortened charge transfer distance, and superior charge separation with respect to the bulk one. Moreover, the as-obtained nanosheets can be employed as effective building block for nanocomposite and heterostructure assembly to further promote charge separation as well as solar hydrogen production from aqueous solution under visible light. The finding of water stable MOF nanosheet under visible light demonstrates its promising future for solar energy conversion.

关键词： metal-organic framework nanosheet water stable photocatalyst nanocomposite