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Spore-pollen-climate factor transfer function and paleoenvironment reconstruction in Dajiuhu,Shennongjia,Central china

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Chinese Science Bulletin 2008年第S1期53卷 42-49页

作者： zhu cheng chen Xing zhang GuangSheng MA ChunMei zhu Qing LI ZhongXuan XU WeiFeng School of Geographic and Oceanographic sciences Nanjing UniversityNanjing 210093China Department of Atmospheric sciences Nanjing UniversityNanjing 210093China

The identified results of 121 surface sediment spore-pollen samples in Shennongjia and meteorological data base of 30 years(January,1971―December,2000)of 7 meteorological stations around Dajiuhu, Shennongjia are used in this *** 55 species of common spore-pollen with the method of space fitting and stepwise regression we construct the pollen climate factor transfer function of annual mean tem- perature:T=7.64.-2.33097X Abies -0.10873X Betula -0.17352X Compositae -0.13176X Cruciferae +0.13356XEuphorbiaceae -0.83069X Campanulaceae +1.964.4.Pyrrosia+0.384.1XPteris+2.7774.XSelaginella+*** had reconstructed annual mean temperature series by use of the sporo-pollen samples concentra-tion percentage in peat section with 297 cm thickness in Dajiuhu since 15.753 *** temperature series reflect well the character of climatic change since the late glacial,which indicates extreme cold climate event of the Oldest Dryas,the Older Dryas,the Younger Dryas and the 8.2 kaBP,the same to the climate fluctuations of Bolling Warm Period and Allerod Warm Period,and the character of temperature change fluctuating frequently at the transition age from the late glacial to the *** reconstructed temperature also indicate Holocene Optimum,late Holocene warm-dry climate,and the character of climatic change in Dajiuhu in the last 1 *** conclusion is that the sporo-pollen samples have important climatic significance to surface sediment and the section of Dajiuhu,Shennongjia and important reference value to studying climatic change during the last glaciation by the temperature transfer function and reconstructed temperature series.

关键词： Dajiuhu Shennongjia Central china spore-pollen climate factor transfer function

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Surveillance on the Immune Effectiveness of Quadrivalent and Trivalent Split Influenza Vaccines—Shenzhen City and Changzhou City,china,2018–2019

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china CDC weekly 2020年第21期2卷 370-375页

作者： Liumei Shu Jie zhang Xiang Huo Cong chen Shisong Fang kexin Zong Yuanyuan Guo Yingze Zhao Jun zhang Changjun Bao Junjie Xia Fengcai {4. Dayan Wang Guizhen Wu George F.Gao William J.Liu NHC Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Jiangsu Provincial Center for Disease Control and Prevention NanjingChina Changzhou Center for Disease Control and Prevention ChangzhouChina Division of Microbiology Test Shenzhen Centre for Disease Control and PreventionShenzhenChina School of Laboratory Medicine and Life sciences Wenzhou Medical UniversityWenzhouChina School of Pharmaceutical sciences Nanjing Tech UniversityNanjingChina CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijingChina.

Summary What is already known about this topic?Vaccinations are the most effective way to prevent influenza virus infections and severe *** vaccine effectiveness can vary by *** is added by this report?This report monitors the antibody level among the population over time after administration of the quadrivalent or trivalent split influenza *** are the implications for public health practice?Real-time monitoring of serum antibody changes after vaccination provides important data for the development of reasonable and effective strategies for influenza prevention and control.

关键词： ent prevention valent

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Study on preparation and properties of CeO_2/epoxy resin composite coating on sintered NdFeB magnet

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Journal of Rare earths 2018年第5期36卷 544-551页

作者： Pengjie zhang minggang zhu Wei Li Guangqing Xu Xiulian Huang Xiaofei Yi Jingwu chen Yucheng Wu School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Central 1ran and Steel Research institute Beijing 100081 China State Key Laboratory of Rare earth Permanent Magnet Materials (earth-Panda Advance Magnetic Material Co. Ltd.) Hefei 231500 China School of Mechanical Engineering Hefei University of Technology Hefei 230009 China

The CeO2/epoxy resin composite coating was deposited on NdFeB substrate by cathode electrophoresis method for enhancing the anticorrosion and anti-wear performances. The morphologies and structures were characterized by a scanning electron microscope and an X-ray diffractometer. The micro hardness of the composite coating was evaluated by a microhardness tester. The corrosive behaviors of the coatings were studied by potentiodynamic polarization curve, electrochemical impedance spectroscopy and neutral salt spray tests. The concentration of CeO2 nanoparticles（NPs） in the electrophoresis bath was optimized according to the coating structures and anticorrosion performances. The results show that CeO2 NPs can enhance the microhardness of the composite coatings. Moreover, the nanoparticles disperse uniformly in the matrix when the concentration is lower than 30 g/L. The microhardness of CeO2/epoxy resin（30 g/L） composite coating is about 63% higher than that of the blank epoxy resin coating. And the NSS time of the CeO2/epoxy resin（30 g/L） composite coated sample can reach 124. ***, the composite coatings possess no deteriorate influence on the magnetic properties of NdFeB substrates. The anticorrosion mechanisms of the composite coatings on the NdFeB substrate are deeply discussed.

关键词： Sintered NdFeB Epoxy resin CeO2 nanoparticle Corrosion resistance Rare earths

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Distribution,cycling and impact of water in the earth's interior

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National Science Review 2017年第6期4卷 879-891页

作者： Huaiwei Ni Yong-Fei Zheng zhu Mao Qin Wang Ren-Xu chen Li zhang CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China School of earth sciences and Engineering Nanjing University

The earth’s deep interior is a hidden water reservoir on a par with the hydrosphere that is crucial for keeping the earth as a habitable planet. In particular, nominally anhydrous minerals(NAMs) in the silicate earth host a significant amount of water by accommodating H point defects in their crystal lattices. Water distribution in the silicate earth is highly heterogeneous, and the mantle transition zone may contain more water than the upper and lower mantles. Plate subduction transports surface water to various depths, with a series of hydrous minerals and NAMs serving as water carriers. Dehydration of the subducting slab produces liquid phases such as aqueous solutions and hydrous melts as a metasomatic agent of the *** melting of the metasomatic mantle domains sparks off arc volcanism, which, along with the volcanism at mid-ocean ridges and hotspots, returns water to the surface and completes the deep water cycle. There appears to have been a steady balance between hydration and dehydration of the mantle at least since the Phanerozoic. earth’s water probably originates from a primordial portion that survived the Moon-forming giant impact, with later delivery by asteroids and comets. Water could play a critical role in initiating plate tectonics. In the modern earth, the storage and cycling of water profoundly modulates a variety of properties and processes of the earth’s interior, with impacts on surface environments. Notable examples include the hydrolytic weakening effect on mantle convection and plate motion, influences on phase transitions(on the solidus of mantle peridotite in particular) and dehydration embrittlement triggering intermediate-to deep-focus earthquakes. Water can reduce seismic velocity and enhance electrical conductivity, providing remote sensing methods for water distribution in the earth’s *** unresolved issues around the deep water cycle require an integrated approach and concerted efforts from multiple disciplines.

关键词： water earth’s interior mantle subduction partial melting

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Preliminary results of strong ground motion simulation for the Lushan earthquake of 20 April 2013,china

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earthquake Science 2013年第3期26卷 191-197页

作者： Gengshang zhu Zhenguo zhang Jian Wen Wei zhang Xiaofei chen School of earth and Space sciences University of Science and Technology of China Laboratory of Seismology and Physics of earth’s Interior University of Science and Technology of China

The earthquake occurred in Lushan County on 20 April, 2013 caused heavy casualty and economic loss. In order to understand how the seismic energy propagates during this earthquake and how it causes the seismic haz- ard, we simulated the strong ground motions from a rep- resentative kinematic source model by zhang et al. （Chin J Geophys 56（4.：14.8-14.1, 2013） for this earthquake. To include the topographic effects, we used the curved grids finite difference method by zhang and chen （Geophys J Int 167（1）：337-353, 2006）, zhang et al. （Geophys J Int 190（1）：358-378, 2012） to implement the simulations. Our results indicated that the majority of seismic energy con- centrated in the epicentral area and the vicinal Sichuan Basin, causing the XI and VII degree intensity. Due to the strong topographic effects of the mountain, the seismic intensity in the border area across the northeastern of Boxing County to the Lushan County also reached IX degree. Moreover, the strong influence of topography caused the amplifications of ground shaking at the moun- tain ridge, which is easy to cause landslides. These results are quite similar to those observed in the Wenchuan earthquake of 2008 occurred also in a strong topographic mountain area.

关键词： Lushan earthquake Strong groundmotion Topographic effects Seismic intensity

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Viable but nonculturable bacteria and their resuscitation:implications for cultivating uncultured marine microorganisms

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Marine Life Science & Technology 2021年第2期3卷 189-203页

作者： Xiao-Hua zhang Waqar Ahmad Xiao-Yu zhu Jixiang chen Brian Austin College of Marine Life sciences and Institute of Evolution&Marine Biodiversity Ocean University of ChinaQingdao266003China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China School of Petrochemical Engineering Lanzhou University of TechnologyLanzhou730050China Frontiers Science Center for Deep Ocean Multispheres and earth System Ocean University of ChinaQingdao266100China Institute of Aquaculture University of StirlingStirlingFK94LAScotlandUK

Culturing has been the cornerstone of microbiology since Robert Koch first successfully cultured bacteria in the late nineteenth century. However, even today, the majority of microorganisms in the marine environment remain uncultivated. There are various explanations for the inability to culture bacteria in the laboratory, including lack of essential nutrients, osmotic support or incubation conditions, low growth rate, development of micro-colonies, and the presence of senescent or viable but nonculturable (VBNC) cells. In the marine environment, many bacteria have been associated with dormancy, as typified by the VBNC state. VBNC refers to a state where bacteria are metabolically active, but are no longer culturable on routine growth media. It is apparently a unique survival strategy that has been adopted by many microorganisms in response to harsh environmental conditions and the bacterial cells in the VBNC state may regain culturability under favorable conditions. The resuscitation of VBNC cells may well be an important way to cultivate the otherwise uncultured microorganisms in marine environments. Many resuscitation stimuli that promote the restoration of culturability have so far been identified;these include sodium pyruvate, quorum sensing autoinducers, resuscitation-promoting factors Rpfs and YeaZ, and catalase. In this review, we focus on the issues associated with bacterial culturability, the diversity of bacteria entering the VBNC state, mechanisms of induction into the VBNC state, resuscitation factors of VBNC cells and implications of VBNC resuscitation stimuli for cultivating these otherwise uncultured microorganisms. Bringing important microorganisms into culture is still important in the era of high-throughput sequencing as their ecological functions in the marine environment can often only be known through isolation and cultivation.

关键词： VBNC Cultivating the uncultured Resuscitation Marine microorganisms

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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 {4. chengyue {4. 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

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珠三坳陷珠江组一段沉积体系演化过程及其控制因素

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地质科技通报 2024年第2期43卷 111-122页

作者：吴太霏王华刘恩涛陈林张璐陈思谢卫东谷志宇张启扬中国地质大学(武汉)资源学院武汉430074 中国地质大学(武汉)海洋学院武汉430074 中海石油(中国)有限公司湛江分公司广东湛江524057

珠江组一段沉积时期是珠三坳陷沉积体系演变的重要时期,由早期的大范围三角洲沉积体系演化为晚期的浅海陆架沉积体系,对其演化过程及控制因素展开研究,不仅有利于揭示海侵过程中沉积体系演化过程,而且对浅海陆架有利沉积相带预测具有指... 详细信息

珠江组一段沉积时期是珠三坳陷沉积体系演变的重要时期,由早期的大范围三角洲沉积体系演化为晚期的浅海陆架沉积体系,对其演化过程及控制因素展开研究,不仅有利于揭示海侵过程中沉积体系演化过程,而且对浅海陆架有利沉积相带预测具有指导意义。综合利用岩心、测井以及高分辨率三维地震资料,建立了珠三坳陷珠江组一段四级层序地层格架,通过地质-地球物理结合方法查明了珠江组一段沉积体系的时空演化特征,并讨论了沉积演化的主控因素。研究表明:珠三坳陷珠江组一段可划分为PS1、PS2、PS3、PS4.4.四级层序。PS3和PS4.期主要发育三角洲前缘沉积,具有水下分流河道、分流间湾、河口坝和远砂坝等沉积微相组合;PS1和PS2时期以浅海陆架沉积体系大规模发育为特征,在研究区西部发育潮流砂脊,东部发育滨外砂坝。珠三坳陷沉积体系的平面展布以及垂向演化受相对海平面变化、物源供给强度、构造沉降与古地貌等综合控制。水下分流河道、潮流砂脊与滨外砂坝等微相砂岩占比高且物性好,为油气储集的有利沉积相带。

关键词：沉积体系控制因素珠江组一段珠三坳陷珠江口盆地浅海陆架层序地层

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Electric-field-controlled magnetism due to field-induced transition of Pna2_(1)/R3c in Bi_(1-x)Gd_(x)FeO_(3) ceramics

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Journal of Materiomics 2021年第5期7卷 967-975页

作者： Jing chen Nan Su Xiao Li zhu Xiao Qiang Liu Jin-Xing zhang Xiang ming chen Laboratory of Dielectric Materials School of Materials Science and EngineeringZhejiang UniversityNo.38 Zheda RoadHangzhou310027China Department of Physics Beijing Normal UniversityNo.19 Xinjiekouwai StBeijing100875China

BiFeO_(3) has been recognized as one of the most important room-temperature single-phase multiferroic materials,but it still suffers from several drawbacks especially the weak magnetoelectric *** the present work,the electric-field-controlled magnetism is achieved in Bi_(1-x)Gd_(x)FeO_(3) system,which involves a field-induced transition of Pna2_(1)/R3c at the morphotropic phase boundary region,and the magnetic state is switched between cycloidal state and canted antiferromagnetic *** electric-field-controlled magnetism becomes reversible with the help of annealing,which is confirmed by magnetic hysteresis loops and the quantitative ratio of the involved phases for the as-sintered,as-poled and as-annealed *** with the systems of Bi_(1-x)Nd_(x)FeO_(3) and Bi_(1-x)Sm_(x)FeO_(3),it is easier to tune the symmetry from R3c to Pna21 with lower rare earth-content,and the field-induced transition is more apparent and subsequently leads to more significant electric-field-controlled magnetism in a wider composition range.

关键词： Bi_(1-x)Gd_(x)FeO_(3) Morphotropic phase boundary Magnetic properties Electric-field-controlled magnetism

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Decorating rare-earth fluoride upconversion nanoparticles on AuNRs@Ag core-shell structure for NIR light-mediated photothermal therapy and bioimaging

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Journal of Rare earths 2022年第2期40卷 193-200,I0001页

作者： Jingzhi Dou Bei chen Guixia Liu Xiangting Dong Wensheng Yu Jinxian Wang Yunxiao zhang zhanguo Li Jiang zhu Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Artificial Micro-and Nano-Structures of ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072China Tianjin Jinhang Technical Physics Institute Tianjin 300070China School of Optoelectronic Engineering Changchun University of Science and TechnologyChangchun 130022China School of Foreign Languages Changchun University of Science and TechnologyChangchun 130022China

Photothermal therapy(PTT)has presented its inherent application value in cancer ***,single-functional photothermal materials cannot meet the precise diagnosis and treatment of cance *** re,it is important to design a nanocomposite that has both high therapeutic efficiency and multimodal imaging *** our work,a new nanostructure of gold nanorods(AuNRs)with silver shells decorated by BaGdF5:Yb^(3+),Er^(3+)nanoparticle was synthesized by a simple *** biostability of AuNRs is increased by coating with silver shells,and the AuNR@Ag nanoparticles can be used as excellent surface enhanced Raman scattering(SERS)***,the modification of BaGdF5:Yb^(3+),Er^(3+)nanoparticles provides the possibility of real-time optical imaging of the tumor *** the irradiation of NIR laser,the AuNR@Ag/BaGdF5:Yb^(3+),Er^(3+)nanocomposites(NCs)have strong upconversion emission and excellent photothermal conversion ***,the NCs show low cytotoxicity and good biocompatibility in MTT cytotoxicity ***,the NCs are also exceptional contrast agents for CT *** in vitro photothermal therapy test,NCs show excellent killing efficiency on tumor ***,the multifaceted research of AuNR@Ag/BaGdF5:Yb^(3+),Er^(3+)multifunctional nanomaterials provides a break for high-efficiency tumor photothermal therapy and multimodal imaging.

关键词： Multifunctional nanocomposites Photothermal therapy Multimodal imaging Rare earths

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