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Journal of Materials Science & Technology 2014年第5期30卷 517-522页

作者： Yuxi Wu wanglin Zhang Jia Guo Jieshan Hou Xiuyan Li renzhong Huang Xiufang Ma Qianfeng Zhang Institute of Molecular Engineering and Applied Chemistry Anhui University of Technology Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences College of Physics Science and Technology Shenyang Normal University

The influence of lattice misfit on the occupation behavior and the ductility effect of Zr in Ni-Ni3Al alloys were explored. It is found in energy analysis that the preferable site of Zr between Ni sublattice and Al sublattice will change under different lattice misfit, however, the Zr prefers to segregate Ni phase rather than Ni3Al phase in all lattice misfit range, which makes it impossible for Zr to go into Ni3Al phase to occupy Al sublattice in Ni-Ni3Al system. Bond order （BO） analysis shows that the localized ductility effect of Zr differs in different region, and the comparison between Zr-free and Zr-doped BO analysis successfully explain the mechanism of the embrittlement of Ni-Ni3Al alloys and the ductility effect of Zr.

关键词： Zirconium Lattice misfit Occupation behavior Ductility Embrittlement

Study of automobile exhaust particles by spectromicroscopy

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Nuclear Science and Techniques 2010年第5期21卷 261-265页

作者： YANG Chuanjun GUO Zhi ZHANG Xiangzhi wang Yong XU Zhijian ZHANG Lijuan TAI renzhong BAO Liangman LI Xiaolin ZHANG Guilin LI Yan Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

In this paper,automobile exhaust particles of Gol and Santana 3000 were studied by *** STXM results show that the single particulate is sized at 500 nm,with the mass distribution reducing towards the *** N 1s NEXAFS spectra of automobile exhaust particles have similar structure with those of nitrates,which can be deduced as the main chemical species of nitrogen in automobile exhaust *** are minor amounts of ammoniums and organic nitrogen compounds in automobile exhaust particles.A single Gol automobile exhaust particle was stack scanned in the energy range of 396-416 *** principal component analysis and cluster analysis,it can be deduced that there are main three chemical species of *** particle surface consists of mainly nitrates,the inside consists of mainly ammonium and organic nitrogen compounds,and the middle layer is an intergradation consisting of mainly nitrates and organic nitrogen compounds.

关键词：汽车废气有机氮化合物桑塔纳3000 汽车尾气粒子化学物质单颗粒主成分分析

Great enhancement of image details with high fidelity in a scintillator imager using an optical coding method

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Photonics Research 2020年第7期8卷 1079-1085页

作者： Huijuan Xia Yanqing Wu Lei Zhang Yuanhe Sun Zhongyang wang renzhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

High-resolution lens-coupled indirect X-ray scintillator imagers are required by many imaging ***,the severe weakening of image details prevents its further performance *** our research,this image degradation is attributed to the broadband loss of the high-spatial-frequency information caused by the high refractive index.A technique known as high-spatial-frequency spectrum enhanced reconstruction is thus proposed to retrieve this information.A two-dimensional high-density array is covered on the scintillator’s exit surface and operates as an encoder based on which high-frequency information can be shifted to the low-frequency region to improve the signal-to-noise *** experimental results show that the middle-high-frequency signal intensities can be increased by an order of magnitude or more,up to^50 ***,the image details can be effectively enhanced to break through the performance bottleneck of such widely used X-ray imagers for synchrotron radiation facilities or tabletop X-ray tubes.

关键词： image details high

Plasmonic Luneburg lens and plasmonic nano-coupler

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Chinese Optics Letters 2020年第9期18卷 59-63页

作者： Lei Zhang Lin wang Yanqing Wu renzhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

In a single nanoscale device, surface plasmon polaritons(SPPs) have potential to match the different length scales associated with photonics and electronics. In this Letter, we propose an accurate design of a plasmonic metasurface Luneburg lens(PMLL) accommodating SPPs. The simulations indicate that the full width at half-maximum is 0.42 μm, and the focus efficiency is 78%. The characters of a PMLL have robustness to manufacturing errors. The PMLL is applied in a 10 μm long compact coupler model, which couples the SPPs to the 40 nm wide output waveguide. The couple efficiency is higher than that of a conventional taper coupler in a broad bandwidth. The design is compatible with standard lithography technology.

关键词： Luneburg nano-coupler plasmonics

Dynamic evolution of oxide scale on the surfaces of feed stock particles from cracking and segmenting to peel-off while cold spraying copper powder having a high oxygen content

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Journal of Materials Science & Technology 2021年第8期67卷 105-115页

作者： Xiao-Tao Luo Yi Ge Yingchun Xie Yingkang Wei renzhong Huang Ninshu Ma Chidambaram Seshadri Ramachandran Chang-Jiu Li State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China The Key Lab of Guangdong for Modem Surface Engineering Technology Guangdong Institute of New MaterialsGuangzhou510651China Joining and Welding Research Institute Osaka UniversityOsaka567-0047fapan Department of Materials Science and Engineering The State University of New York at Stony BrookNew York117942275USA

The oxide scale present on the feedstock particles is critical for inter-particle bond formation in the cold spray(CS)coating process,therefore,oxide scale break-up is a prerequisite for clean metallic contact which greatly improves the quality of inter-particle bonding within the deposited *** general,a spray powder which contains a thicker oxide scale on its surface(i.e.,powders having high oxygen content)requires a higher critical particle velocity for coating formation,which also lowers the deposition efficiency(DE)making the whole process a challenging *** this work,it is reported for the first time that an artificially oxidized copper(Cu)powder containing a high oxygen content of 0.81 wt.%with a thick surface oxide scale of 0.71μm.,can help achieve an astonishing increment in DE.A transition of surficial oxide scale evolution starting with crack initiations followed by segmenting to peeling-off was observed during the high velocity particle impact of the particles,which helps in achieving an astounding increment in ***-particle deposit observations revealed that the thick oxide scale peels off from most of the sprayed powder surfaces during the high-velocity impact,which leaves a clean metallic surface on the deposited *** makes the successive particles to bond easily and thus leads to a higher ***,owning to the peeling-off of the oxide scale from the feedstock particles,very few discontinuous oxide scale segments are retained at inter-particle boundaries ensuring a high electrical conductivity within the resulting *** of the oxide scale threshold thickness for peeling-off during the high velocity particle impact was also investigated.

关键词： Cold spray Deposition efficiency Oxide scale fragmentation Inter-particle bonding Electrical conductivity

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新型酚醛树脂软模板法制备微孔碳

河北科技师范学院学报 2019年第1期33卷 67-72页

作者：孙明功杜晶晶韩丽娜郭海勃李鹏旺李博文张馨方王仁忠薄鹏冲王利江方明张志伟河北科技师范学院化学工程学院河北秦皇岛066600

针对微孔碳的制作工艺复杂、成本较高的缺点,采用新型酚醛树脂软模板法试验制备了微孔碳,该方法工艺简单、成本较低,通过改变酚醛树脂的原料配比和搅拌方式来考察上述因素对微孔碳的形貌和孔径的影响。结果表明,当m(苯酚)∶m(甲醛溶液)... 详细信息

针对微孔碳的制作工艺复杂、成本较高的缺点,采用新型酚醛树脂软模板法试验制备了微孔碳,该方法工艺简单、成本较低,通过改变酚醛树脂的原料配比和搅拌方式来考察上述因素对微孔碳的形貌和孔径的影响。结果表明,当m(苯酚)∶m(甲醛溶液)∶m(H_2O)∶m(Na_2CO_3)为1∶6∶80∶0.010和m(葡萄糖酸)∶m(ZnCl_2)∶m(HCl)∶m(H_2O)为1∶2∶6∶20时,制备的微孔碳球直径在2～5μm,比表面积达670 m^2·g^(-1),平均孔径在0.37 nm。

关键词：球形微孔碳模板法酚醛树脂

Oxidative C—H alkynylation of 3,6-dihydro-2H-pyrans

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Chinese Chemical Letters 2019年第7期30卷 1432-1434页

作者： Ran Zhao Guidong Feng Xiaodong Xin Honghao Guan Jing Hua renzhong Wan Wei Li Lei Liu Department of Pharmaceutical Analysis School of Pharmacy Shandong University of Traditional Chinese Medicine Ji'nan 250355 China College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal University Guilin 541004 China

Current synthesis of α-substituted 3,6-dihydro-2H-pyrans dominantly relies on functional group transformation. Herein, a direct and practical oxidative C -H alkynylation and alkenylation of 3,6-dihydro-2H-pyran skeletons with a range of potassium trifluoroborates is developed. The metal-free process is well tolerated with a wide variety of 3,6-dihydro-2H-pyrans, rapidly providing a library of 2,4-disubstituted 3,6-dihydro-2H-pyrans with diverse patterns of α-functionalities for further diversification and bioactive small molecule identification.

关键词： 3,6-Dihydro-2H-pyrans C-H Functionalization Alkynylation Oxidation Organoborane

Epidemiological Characteristics of Rifampicin-Resistant Tuberculosis in Students——China,2015-2019

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China CDC weekly 2021年第26期3卷 549-552页

作者： Wei Su Yunzhou Ruan Tao Li Xin Du Jiawen Jiang Yuying He renzhong Li National Center for Tuberculosis Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Guizhou Provincial Center for Disease Control and Prevention GuiyangGuizhouChina

Summary What is already known about this topic?The number of students with tuberculosis(TB)has been increasing since ***,the prevalence of rifampicin-resistant tuberculosis(RR-TB)among student population is *** is added by the report?The number of students with RR-TB has significantly increased from 2015 to 2019,especially in the western region of *** majority of patients were college *** with RR-TB were mainly new patients.

关键词： has since among tuberculosis

中医药治疗过敏性鼻炎的CiteSpace知识图谱分析

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西部中医药 2024年第12期37卷 91-96页

作者：杨祺王玉明孟伟韩秀丽王仁忠山东中医药大学附属医院山东济南250011

目的:分析近20年来中医药治疗过敏性鼻炎的主要研究内容、研究趋势、作者及机构合作现状。方法:在中国知网(CNKI)核心期刊内检索2000—2020年中医药治疗过敏性鼻炎的相关文献,利用CiteSpace进行作者、机构合作共现分析及关键词共现、聚... 详细信息

目的:分析近20年来中医药治疗过敏性鼻炎的主要研究内容、研究趋势、作者及机构合作现状。方法:在中国知网(CNKI)核心期刊内检索2000—2020年中医药治疗过敏性鼻炎的相关文献,利用CiteSpace进行作者、机构合作共现分析及关键词共现、聚类、突现分析。结果:共纳入文献529篇,平均每年核心发文量在35篇左右;发表核心文献的作者有557名,分别形成以严道南、闫占峰、刘大新为核心的合作团队,机构合作密度为0.0029;关键词共现得出中医药治疗过敏性鼻炎的主要研究内容包括过敏性鼻炎、变应性鼻炎、慢性鼻炎、哮喘、玉屏风散、免疫球蛋白E、针刺、名医经验、随机对照试验等;关键词聚类得出17个聚类;突现分析得到15个关键词,当前的研究热点以过敏性鼻炎-哮喘综合征、名医经验、作用机制、临床疗效为主。结论:随着对中医药治疗过敏性鼻炎的深入,治疗方法逐渐丰富完善,但各地区之间还需加强信息交流与合作,为该领域提供新的思路与方向。

关键词：过敏性鼻炎中医药治疗知识图谱 CiteSpace

The fractal or scaling perspective on progressively generated intra-urban clusters from street junctions

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International Journal of Digital Earth 2023年第1期16卷 1944-1961页

作者： Biao He renzhong Guo Minmin Li Ying Jing Zhigang Zhao Wei Zhu Chen Zhang Chengyue Zhang Ding Ma Research Institute for Smart Cities School of Architecture and Urban PlanningShenzhen University&MNR Technology Innovation Center of Territorial&Spatial Big Data&MNR Key Laboratory of Urban Land Resources Monitoring and Simulation&Guangdong-Hong Kong-Macao Joint Laboratory for Smart CitiesShenzhenPeople’s Republic of China Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) ShenzhenPeople’s Republic of China Ningbo Institute of Technology School of EconomicsZhejiang UniversityNingboPeople’s Republic of China School of Resource and Environmental Sciences Wuhan UniversityWuhanPeople’s Republic of China

The underlying complexity of urban space can be manifested by its fractal forms and scaling *** paper examines these characteristics at the intra-urban scale through the lens of clustered street junctions(including road ends)in two Chinese metropolitan areas:Beijing and *** derived the cluster sets with Euclidean distance thresholds starting at 100 meters(m)and ending at 1000 m,and outlined each cluster using a concave-hull method to maintain their original irregular *** each delimited cluster,we examined four urban attributes:gross domestic product,number of street nodes,polygon area,and *** analysis revealed that power law distribution applied to almost every cluster set in terms of the four attributes,but varied from one attribute to another or from city to city,represented primarily byfluctuated power law exponents and ht-index values whose profiles along with the cluster growth can effectively characterize the urban ***,we computed the spectrum of intra-urban scaling exponents with cluster size increments,contributing new insights into the allometric relationships between urban configuration and function.

关键词： Spatial clustering urban structure urban function power law intra-urban scaling law