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Regional Geochemistry and Fluid Flow in the Palaeogene Aquifers of the Gaoyou Subbasin in the Southern Part of North Jiangsu Basin, China

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 946-955页

作者： li mei Shanghai Geotechnical Investigations & Design Institute Co. Ltd

Chemical analysis of groundwater in petroliferous basins can be an effective way to determine the regional hydrogeological regime and to evaluate the preservation conditions of hydrocarbons. This paper presents the hydrochemical distribution of both individual aquifers and different structural units within the Palaeogene strata of the Gaoyou subbasin in the North Jiangsu Basin, east China. The results show that the salinity of the Palaeogene aquifers in the Gaoyou subbasin displays a systematic increase from the central deep depression to the periphery areas, and shows a reverse trend as the burial depth increases. Salinity maps of individual aquifers suggest that formation water in the deep layers at the centre of the study area probably retains original features of fresh lake water. Geofluids near the central deep depression of the Gaoyou subbasin migrate vertically through the Zhenwu and Hanliu faults, while those of the northern slope belt mainly flow laterally through aquifers. Both low and high salinity formation water can be found in the hydrocarbon producing areas. The low salinity zones commonly affected by infiltrated meteoric water are unfavourable conditions for the preservation of trapped hydrocarbons.

关键词： regional hydrogeology hydrochemistry hydrocarbon preservation North Jiangsu Basin

Dynamics of Periodic Waves in Bose-Einstein Condensate with Time-Dependent Atomic Scattering Length

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Communications in Theoretical Physics 2007年第1期47卷 63-68页

作者： li Hua-mei Department of Physics Zhejiang Normal University Jinhua 321004 China

Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method, we successfully obtain periodic wave solutions and solitary wave solutions, including the bright and dark soliton *** results in this paper include some in the literatures [Phys. Rev. Lett. 94 （2005） 050402 and Chin. Phys. Left. 22 （2005） 1855].

关键词： Gross-Pitaevskii equation periodic wave time-dependent atomic scattering length mapping deformation method

ANALYSIS OF ECOLOGICAL FLOW FIELD IN AN ONCEMELANIA-FREE WATER INTAKE DEVICE

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Journal of Hydrodynamics 2005年第3期17卷 301-305页

作者： FUXiao-li liDa-mei DepartmentofRiverEngineering WuhanUniversityWuhan430072China

Oncemelania is the middle-parasitifer of schistosome. Controlling the oncomelania is the important way of preventing the schistosomiasis. The article mainly introduces the measurement of jet flow field’s velocity in pressure conduit by FVM numerical modeling and using high-tech PIV, and analyses the reason why the Oncemelania could sink to the bottom but not escape from the equipment named Oncemelania-free intake devices.

关键词： oncomelania oncemelania-free intake mechanism of oncomelania’s sinking

The spreading fronts in a mutualistic model with delay

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International Journal of Biomathematics 2016年第6期9卷 1-16页

作者： mei li School of Applied Mathematics Nanjing University of Finance and Economics Nanjing 210023 P. R. China Institute of Mathematics Nanjing Normal University Nanjing 210023 P. R. China

This paper is concerned with a system of semilinear parabolic equations with two free boundaries describing the spreading fronts of the invasive species in a mutualistic eco- logical model. The local existence and uniqueness of a classical solution are obtained and the asymptotic behavior of the free boundary problem is studied. Our results indi- cate that two free boundaries tend monotonically to finite or infinite limits at the same time, and the free boundary problem admits a global slow solution with unbounded free boundaries if the intra-specific competitions are strong, while if the intra-specific competitions are weak, there exist the blowup solution and global fast solution.

关键词： Free boundary mutualistic model blowup global fast solution global slowsolution.

Non-linear Radical Additions-Coupling Polymerization of Monovinyl Monomers towards Polymer Networks: Theory, Tunability and Heritable Architecture

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Chinese Journal of Polymer Science 2022年第12期40卷 1623-1630,I0008页

作者： li-mei Ren Cheng-lin li Qi Wang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science&Engineering Zhejiang UniversityHangzhou 310027China Current address:Zhejiang University-University of Edinburgh Institute Zhejiang University School of Medicineand Key Laboratory of Tissue Engineering and Regenerative Medicine of Zhejiang ProvinceZhejiang University School of MedicineHangzhou 310027China

Exploring new polymerization strategy for current available monomers is a big challenge in polymer science. Here we re-investigate radical polymerization of monovinyl monomer(MVM) initiated by uniform branched polyfunctional initiator(PFI), which is termed non-linear radical additions-coupling polymerization(NLRAs CP). In NLRAs CP, both addition and coupling reactions of radical contribute to the construction of the polymer chains, which leads to continuous growth of branch topology. Theoretical analysis of NLRAs CP predicts that the gelation is determined by the functionality of PFI(a), the extent of initiation of the PFI(q) and the termination factor of radical(φ). NLRAs CPs of styrene and methyl methacrylate promoted by Cu(0)/MeTREN or Mn_(2)(CO)_(10)/visible light were conducted. After the cleavage of incorporated PFI fragment or junctions in the network, the network was transformed to linear chains having almost the same structure as segmental chains in the precursor network. This allows the reverse deducing the network structure from its cleaved products. It has been proven that NLRAs CP includes stepwise initiation of PFI, chain-growth of segmental chains and successive endlinking of macroradicals derived from PFI. The three parameters related to the gelation process, a, q and φ, were adjusted via binary PFI, the feed ratio of [Mn_(2)(CO)_(10)]/[PFI] and addition of non-homopolymerizable comonomer respectively. The minimum values of a and q, and the minimum amount of comonomer required for gelation were determined,which can be applied to estimate φ of various macroradicals. NLRAs CP opens a general and facile strategy for synthesis of a variety of polymer networks with heritable architecture by one-pot polymerization of various MVMs.

关键词： Non-linear radical additions-coupling polymerization Monovinyl monomer Polyfunctional initiator Polymer network Theory

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Communications in Theoretical Physics 2009年第2期51卷 279-282页

作者： li Hua-mei Department of Physics Zhejiang Normal University Jinhua 321004 China

This paper analyzes spatial grey self-similar solitary waves propagation and collision in graded-index nonlinear waveguide amplifiers with self-focusing and self-defocusing Kerr nonlinearities. New exact self-similar solutions are found using a novel transformation and their main features are investigated by using direct computer simulations.

关键词： grey self-similar solitary wave inhomogeneous nonlinear media collision

Effect of intermetallic phases on the anodic oxidation and corrosion of 5A06 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 167-174页

作者： Song-mei li Ying-dong li You Zhang Jian-hua liu mei Yu School of Materials Science and Engineering Beihang University

Intermetallic phases were found to influence the anodic oxidation and corrosion behavior of 5A06 aluminum alloy. Scattered in- termetallic particles were examined by scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS） after pretreatment. The anodic film was investigated by transmission electron microscopy （TEM）, and its corrosion resistance was analyzed by electrochemical impedance spectroscopy （EIS） and Tafel polarization in NaC1 solution. The results show that the size of A1-Fe-Mg-Mn particles gradually decreases with the iron content. During anodizing, these intermetallic particles are gradually dissolved, leading to the complex porosity in the anodic film beneath the particles. After anodizing, the residual particles are mainly silicon-containing phases, which are embedded in the an- odic film. Electrochemical measurements indicate that the porous anodic film layer is easily penetrated, and the barrier plays a dominant role in the overall protection. Meanwhile, self-healing behavior is observed during the long immersion time.

关键词： aluminum alloys intermetallic particles anodic oxidation corrosion protective films

Progress and prospects of noncoding RNAs in insects

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Journal of Integrative Agriculture 2019年第4期18卷 729-747页

作者： li mei-zhen XIAO Hua-mei HE Kang li Fei Ministry of Agriculture Key Lab of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences College of Agriculture and Biotechnology Zhejiang University College of life Sciences and Resource Environment Yichun University

With the rapid development of high-throughput sequencing technology and bioinformatics algorithms, great progress has been made in the field of noncoding RNA(ncRNA) in the last decade. RNA molecules have been regarded only as a messenger between DNA and protein for decades, but now they have new roles in the biological process as ncRNAs. A growing number of ncRNAs have been identified in insects from the RNA-Seq data of small RNA libraries or transcriptomes. ncRNAs have varied regulatory functions at the epigenetic, transcriptional, or post-transcriptional levels, and participate in almost all types of biological processes. Here, we review the research progress of four kinds of ncRNAs, including microRNA(miRNA), Piwiinteracting RNA(piRNA), circular RNA(circRNA), and long noncoding RNA(lncRNA) in insects. The discovery, biogenesis mechanisms, and regulatory functions of these ncRNAs are presented here to provide a comprehensive understanding of insect ncRNAs and to promote the application of ncRNAs in insect pest control.

关键词： miRNA piRNA circRNA lncRNA biogenesis prediction regulatory functions

Influence of Rust Layers on the Corrosion Behavior of Ultra-High Strength Steel 300M Subjected to Wet–Dry cyclic Environment with Chloride and Low Humidity

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 139-146页

作者： Qiang Guo Jian-Hua liu mei Yu Song-mei li Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and Engineering Beihang University

The influence of rust layers on the corrosion behavior of ultra-high strength steel 300M subjected to a simulated coastal atmosphere was investigated by corrosion weight loss, surface analysis techniques, and electrochemical methods. The results exhibit the presence of a large proportion of γ-FeOOH and α-FeOOH and a small amount of Fe3O4 in the outer rust layer. During the wet-dry cyclic process, the bonding performance and the density of outer rust layer deteriorate with the thickness of outer rust. The inner rust layer plays a main role on protectiveness, which can be attributed to the formation of an ultra-dense and adherent rust film with major constituent of α-FeOOH and α-Fe2O3 on the steel.

关键词： Ultra-high strength steel Wet-dry Chloride Corrosion Rust