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Characteristics, formation and evolution of pre-salt dolomite reservoirs in the fifth member of the Ordovician Majiagou formation, mid-east Ordos Basin, NW China

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Petroleum Exploration and Development 2019年第6期46卷 1153-1164页

作者： FU Siyi ZHANG Chenggong CHEN Hongde CHEN Anqing ZHAO Junxing SU Zhongtang YANG Shuai WANG Guo MI Wentian State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China School of Mines Inner Mongolia University of TechnologyHohhot 010051China

The characteristics and formation of the pre-salt dolomite reservoirs in the fifth member of Ordovician Majiagou formation in the mid-east Ordos Basin are investigated through observation of cores and thin sections,and geochemical analysis.(1)The pre-salt dolomites can be divided into dolomicrite,grain dolomite and dolarenite,in which the main reservoir space consists of intercrystalline pores and various dissolved pores.(2)The diagenesis in the study area is complex and mainly includes dolomitization,dissolution,filling,and recrystallization.(3)Multi-stages of dolomitization,including penecontemporaneous capillary concentration dolomitization,seepagereflux dolomitization during penecontemporaneous and shallow burial stage,and burial dolomitization in later stage,are conducive to the preservation of primary pores and development of secondary pores.(4)Multi-stages of dissolution also have strong influence on the development of secondary pores;the secondary transgression and regression cycles during the contemporaneous-penecontemporaneous stage led to exposure and dissolution of soluble minerals and thus the generation of secondary pores.(5)In the burial stage,reservoir pores were further improved due to organic acid dissolution and the dissolution by hydrosulphuric acid from thermochemical sulfate reduction(TSR)and its product H2S.(6)High H2S concentration area in pre-salt reservoirs can thus be considered as targets for future exploration.

关键词： Ordos Basin Ordovician Majiagou formation dolomite evaporites dolomitization dissolution

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formation of choroidal neovascularization under macular fovea after high-power laser irradiation: a case report

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International Journal of Ophthalmology(English edition) 2020年第2期13卷 359-361页

作者： Shan-Shan Li Xiao-Ran Chu Fang Chen Department of Ophthalmology Northern Jiangsu People’s HospitalYangzhou 225001Jiangsu ProvinceChina Dalian Medical University Dalian 116044Liaoning ProvinceChina

Dear Editor,I am Dr.Shan-Shan Li,from Northern Jiangsu People’s Hospital,Yangzhou,China.I write to present the case of formation of choroidal neovascularization(CNV)under the fovea after high-power laser irradiation.Currently,there is an increasing availability and accessibility to laser instruments,but improper use of these tools can lead to macular damage and irreversible visual impairment.

关键词： FFA a case report formation of choroidal neovascularization under macular fovea after high-power laser irradiation

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Neuroligins Differentially Mediate Subtype-Specific Synapse formation in Pyramidal Neurons and Interneurons

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Neuroscience Bulletin 2019年第3期35卷 497-506页

作者： Qiang-Qiang Xia Jing Xu Tai-Lin Liao Jie Yu Lei Shi Jun Xia Jian-Hong Luo Junyu Xu Department of Neurobiology Institute of NeuroscienceNHC and CAMS Key Laboratory of Medical NeurobiologyZhejiang University School of MedicineHangzhou 31005& China JNU-HKUST Joint Laboratory for Neuroscience and Innovative Drug Research. Jinan University Guangzhou 510632China Division of Life Science Division of Biomedical Engineering and State Key Laboratory of Molecular Neuroscience. The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Neuroligins(NLs) are postsynaptic cell-adhesion proteins that play important roles in synapse formation and the excitatory-inhibitory balance. They have been associated with autism in both human genetic and animal model studies, and affect synaptic connections and synaptic plasticity in several brain regions. Yet current research mainly focuses on pyramidal neurons, while the function of NLs in interneurons remains to be understood. To explore the functional difference among NLs in the subtypespecific synapse formation of both pyramidal neurons and interneurons, we performed viral-mediated shRNA knockdown of NLs in cultured rat cortical neurons and examined the synapses in the two major types of neurons. Our results showed that in both types of neurons, NL1 and NL3 were involved in excitatory synapse formation, and NL2 in GABAergic synapse formation. Interestingly, NL1 affectedGABAergic synapse formation more specifically than NL3,and NL2 affected excitatory synapse density preferentially in pyramidal neurons. In summary, our results demonstrated that different NLs play distinct roles in regulating the development and balance of excitatory and inhibitory synapses in pyramidal neurons and interneurons.

关键词： Neuroligin Synapse formation Excitatory/inhibitory balance Interneuron

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Tiller Bud formation Regulators MOC1 and MOC3 Cooperatively Promote Tiller Bud Outgrowth by Activating F0N1 Expression in Rice

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Molecular Plant 2019年第8期12卷 1090-1102页

作者： Gaoneng Shao Zefu Lu Jinsong Xiong Bing Wang Yanhui Jing Xiangbing Meng Guifu Liu Haiyan Ma Yan Liang Fan Chen Yonghong Wang Jiayang Li Hong Yu State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing) Institute of Genetics and Developmental BiologyThe Innovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Rice Biology China National Rice Research InstituteHangzhou 310006China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyThe Innovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China Present address: Department of Genetics University of GeorgiaAthensGA 30605USA Present address: College of Horticulture Nanjing Agricultural UniversityNanjingJiangsu 210095China

Tillering in rice is one of the most important agronomic traits.Rice tiller development can be divided into two main processes: the formation of the axillary bud and its subsequent outgrowth.Several genes critical for bud formation in rice have been identified by genetic studies;however,their molecular functions and relationships are still largely unknown.Here,we report that MONOCULM 1 (MOC1) and MONOCULM 3/ TILLERS ABSENT 1/STERILE AND REDUCED TILLERING 1 (MOC3/TAB1/SRT1),two vital regulators for tiller formation in rice,physically interact to regulate tiller bud outgrowth through upregulating the expression of FLORAL ORGAN NUMBER 1 (FON1),the homolog of CLAVATA1 in rice.We found that M0C3 is able to directly bind the promoter ofFONI and subsequently activate FON1 expression.MOC1 functions as a coactivator of MOC3,whereas it could not directly bind the FON1 promoter,and further activated FON1 expression in the presence of MOC3.Accordingly,FON1 is highly expressed at axillary meristems and shows remarkably decreased expression levels in mod and moc3 mutants.Loss-of-function mutants of FON1 exhibit normal bud formation but defective bud outgrowth and reduced tiller number.Collectively,these results shed light on a joint transcriptional regulatory mechanim by MOC1 and MOC3,and establish a new framework for the control of tiller bud formation and outgrowth.

关键词： rice tiller formation MOC3 M0C1 FON1

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formation and Dielectric Properties of Mn-Doped BSTN Composite Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 1-3页

作者：周宗辉 School of Materials Science and Engineering University of Jinan

The influence of Mn doping on the formation and dielectric properties of 0.7BaO·0.3SrO·（1-y）TiO2·yNb2O5 （BSTN） composite ceramics were investigated. The Mn was doped according to the formula 0.7BaO·0.3SrO·（0.7-z）TiO2·0.3Nb2O5·zMnO2 （BSTNM）. The results show the two phases, perovskite phase BST and the tungsten bronze phase SBN, are coexistence in BSTNM as they are in BSTN composite ceramics. The Mn ions doped in BSTN substitute for Nb5＋ ions in the tungsten bronze phase, and then, the Nb5＋ ions substitute for Ti4＋ ions in the perovskite phase. With the increasing of Mn dopant, the content of the perovskite phase increases while that of the tungsten bronze phase decreases, and the grain size of the perovskite phase decreases. As well as, the phase transition temperature of tungsten bronze phase increases with value z increasing from 0 to about 0.05.

关键词： Mn BSTN Composite ceramics formation Dielectric properties

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An overview of the 2018 second class State Natural Science Award—North China Craton:formation and revolution of the oldest continent in China

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Science Bulletin 2019年第10期64卷 641-643页

作者： Yu-Sheng Wan Dun-Yi Liu Biao Song Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences

The formation, composition and evolution of the oldest continental crust is the logical starting point for discussing the differentiation and development of the crust-mantle system and the tectonic evolution of the Earth. Searching for and identifying the oldest continental crust and investigating the processes and periodicity of crust formation and its subsequent development into cratons is a primary scientific topic of worldwide research [1]. The other important issues related to early Precambrian evolution include identifying tectonic divisions and determining the onset of plate tectonics. However, the rarity of preserved ancient continental crust due to its long-term reworking makes this research extremely challenging. Thus, finding and identifying the oldest rocks and zircons is the beginning of very exciting and important research. The occurrence of >3.8 Ga rocks in northern and eastern Canada, West Greenland and eastern Antarctica are difficult to access and so it is important to identify other occurrences of such rocks.

关键词： The formation oldest continental crust eastern Antarctica

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Modeling turbulent transport effects on kernel formation and ?ame propagation in an ignition process

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Chinese Journal of Aeronautics 2019年第4期32卷 895-905页

作者： Linghan KONG Zhuyin REN Lingyun HOU School of Aerospace Engineering Tsinghua University

Reliable relighting is crucial for advanced low-emission aero-engine combustors. For forced ignition under highly-turbulent conditions, eddies of sizes being smaller than the flame kernel can affect its formation through penetrating and modifying the kernel structure. In this study, a one-dimensional model for small-scale turbulence on kernel formation is developed through the incorporation of turbulence-induced diffusion in governing equations. With given flow conditions,the spatial and time-dependent turbulent diffusivity is modeled using the idea of residual eddy viscosity. One-dimensional spherical flames of premixed pre-vaporized n-dodecane/air mixtures under high-altitude conditions are simulated to investigate the effects of turbulence. It is revealed that the range of the equivalence ratio for successful turbulent ignition is much narrower than that for laminar ignition. The range decreases with an increased turbulent intensity, and this effect is more pronounced for a low spark energy. In addition, turbulent transport has more pronounced effects on rich mixtures. An analysis on energy budget and species profiles shows that turbulence-induced diffusion enhances the heat loss at the very beginning of the kernel formation process that could lead to ignition failure. After the flame kernel is established, turbulent transport broadens the flame front, enhances the heat release rate, and thereafter increases the flame propagation speed.

关键词： Flame kernel Flame propagation High-altitude ignition Kernel formation probability Turbulence-induced diffusion

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formation and obstacle avoidance control for multiagent systems

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控制理论与应用（英文版） 2011年第2期9卷 141-147页

作者： Yan, Jing Guan, Xinping Luo, Xiaoyuan Tan, Fuxiao Institute of Electrical Engineering Yanshan University Qinhuangdao Hebei 066004 China School of Electronic and Electric Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Computer and Information Fuyang Teachers College Fuyang Anhui 236041 China

This paper considers the problems of formation and obstacle avoidance for multiagent systems.The objective is to design a term of agents that can reach a desired formation while avoiding collision with obstacles.To reduce the amount of information interaction between agents and target,we adopt the leader-follower formation strategy.By using the receding horizon control (RHC),an optimal problem is formulated in terms of cost minimization under constraints.Information on obstacles is incorporated online as sensed in a limited sensing range.The communication requirements between agents are that the followers should obtain the previous optimal control trajectory of the leader to each update time.The stability is guaranteed by adding a terminal-state penalty to the cost function and a terminal-state region to optimal problem.Finally,simulation studies are provided to verify the effectiveness of the proposed approach.

关键词： Multiagent systems formation Obstacle avoidance Receding horizon control (RHC)

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formation at low surfactant concentrations and characterization of mesoporous MCM-41

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Science China Chemistry 1997年第3期40卷 278-285页

作者：陈晓银丁国忠陈海鹰李全芝 Department of Chemistry Fudan UniversityShanghai 200433China

At low concentrations of cetyltrimethylammonium bromide,all silica-based mesoporous materials with hexagonal phase have been synthesized via interactions between self-assembled surfactant molecule aggregates and aniomc silicate polymers.The resulting materials are characterized by XRD,FT-IR,solid state 29Si MAS NMR,thermal analysis and N2 adsorption-desorption measurements.After soluble ions are removed,the interactors between surfactant micelles and silicate polymers are reorganized and then form mesostructures 1 he hexagonal framework is sonsistent with amorphous silica gel.The structures of materials depend on the synthesis conditions Hydrothermal process improves the interactions between molecules and increases the degree of framework silicon atom polymerization The.surface area and the mesopore volume of the material prepared at 100℃ increase by 87% and 71 %,respectively,compared with those obtained at room temperature.

关键词： low concentration surfactant cetyltrimethylammonium bromide sodium silicate formation of MCM-41 characterization

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Time-varying formation tracking for uncertain second-order nonlinear multi-agent systems

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 76-87页

作者： Mao-peng RAN Li-hua XIE Jun-cheng LI School of Electrical and Electronic Engineering Nanyang Technological University

Our study is concerned with the time-varying formation tracking problem for second-order multi-agent systems that are subject to unknown nonlinear dynamics and external disturbance, and the states of the followers form a predefined time-varying formation while tracking the state of the leader. The total uncertainty lumps the unknown nonlinear dynamics and the external disturbance, and is regarded as an extended state of the agent. To estimate the total uncertainty, we design an extended state observer(ESO). Then we propose a novel ESO based time-varying formation tracking protocol. It is proved that, under the proposed protocol, the ESO estimation error and the time-varying formation tracking error can be made arbitrarily small. An application to the target enclosing problem for multiple unmanned aerial vehicles(UAVs) verifies the effectiveness and superiority of the proposed approach.

关键词： Multi-agent system Time-varying formation formation tracking Nonlinear dynamics Extended state observer(ESO)

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