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Distinguishing the main components of submarine groundwater and estimating the corresponding fluxes based on radium tracing method—taking the Maowei Sea for example

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Acta Oceanologica Sinica 2023年第8期42卷 1-23页

作者： linwei li Jinzhou Du Xilong Wang Yanling Lao State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 201100China Guangxi Key Laboratory of Marine Environmental Change and Disaster in the Beibu Gulf Beibu Gulf UniversityQinzhou 535011China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China College of Resources and Environment Beibu Gulf UniversityQinzhou 535011China

Submarine groundwater discharge(SGD)is an important part in the land-sea interactions,which mainly contains three components:submarine fresh groundwater discharge(SFGD),tidal flat recirculated saline groundwater discharge(tidal flat RSGD)and subtidal recirculated saline groundwater discharge(subtidal RSGD).In order to make a more accurate assessment of the impact of SGD on coastal ecological environment,it is necessary to distinguish the main components of *** this study,the Maowei Sea,located in the northern part of the Beibu Gulf,was selected as the study *** on the radium(Ra)tracing method,we present a new analytical method for distinguishing the three main components of SGD in this area combined with field *** average daily flow along the coastline of the Maowei Sea of tidal flat RSGD was slightly higher than that of SFGD,and both two were on the magnitude of 1×10^(5)m^(3)/*** average daily flow for the subtidal RSGD of the entire subtidal zone of the Maowei Sea reached to the magnitude of 1×10^(6)-1×10^(7)m^(3)/*** long-term variation trend of terrestrial SGD is a valuable information for the study of the influence of terrigenous material on the coastal ecological *** on the results of four sampling periods,it is found that the fluxes of SFGD and tidal flat RSGD in the Maowei Sea had good linear correlation with the net *** an example,January 2015 to August 2022 were selected as the study periods,and the variation trends of SFGD and tidal flat RSGD were calculated by linear function with net precipitation as the independent *** results showed that the flux of tidal flat RSGD was slightly higher than that of SFGD,and the difference between the two is larger in flood season while smaller in dry *** general,in the coastal range of China,the total SGD flux in the Maowei Sea area is at a high level,and the SFGD flux is at a medium level.

关键词： submarine groundwater discharge bottom sediment radium tracing method offshore transport long-term monitoring

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Synthesis, Characterization, DNA-binding Properties and DNA Cleavage of a New Ternary Copper（ll） Complex with Mixed-ligands of Tridentate Schiff Base and 1,10-Phenanth roline

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Chinese Journal of Chemistry 2011年第2期29卷 259-266页

作者： Dong Jianfang li lianzhi li linwei Xu Tao Wang Daqi School of Chemistry and Chemical Engineering Liaocheng University Liaocheng Shandong 252059 China Department of Material Science Shandong Polytechnic Technician College Liaocheng Shandong 252027 China

A new copper（II） complex, [Cu（naph-leu）phen]CH3OH,0.5H20, in which naph-leu is the tridentate Schiff base ligand derived from the condensation of 2-hydroxy-l-naphthaldehyde and L-leucine, phen is phenanthroline, has been synthesized and characterized by elemental analyses, IR spectra and single crystal X-ray diffraction. The DNA-binding properties of this complex have been investigated by absorption spectra, fluorescence spectra and circular dichroism （CD） spectra, as well as viscosity measurement. Results show that this copper（II） complex binds to calf thymus DNA （CT-DNA） in an intercalative mode and its intrinsic binding constant Kb is 4.87 × 10^3 ***^-1. Furthermore, the DNA cleavage activity of this copper（II） complex has also been investigated by submarine gel electrophoresis. Interestingly, it was found that this complex can cleave the supercoiled plasmid pBR322 DNA to both nicked and linear forms.

关键词： copper L-leucine Schiff base crystal structure DNA binding DNA cleavage

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Numerical research on lid-driven cavity flows using a three-dimensional lattice Boltzmann model on non-uniform meshes

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Science China(Technological Sciences) 2013年第9期56卷 2178-2187页

作者： TANG Xuelin SU YanWen WANG FuJun li linwei College of Water Resources and Civil Engineering China Agricultural University

A lattice Boltzmann model combined with curvilinear coordinate is proposed for lid-driven cavity three-dimensional (3D) flows. For particle velocity distribution, the particle collision process is performed in physical domain, and the particle streaming process is carried out in the corresponding computational domain, which is transferred from the physical domain using interpolation method. For the interpolation calculation, a second-order upwind interpolation method is adopted on internal lattice nodes in flow fields while a second-order central interpolation algorithm is employed at neighbor-boundary lattice nodes. Then the above-mentioned model and algorithms are used to numerically simulate the 3D flows in the lid-driven cavity at Reynolds numbers of 100, 400 and 1000 on non-uniform meshes. Various vortices on the x-y, y-z and x-z symmetrical planes are successfully predicted, and their changes in position with the Reynolds number increasing are obtained. The velocity profiles of u component along the vertical centerline and w component along the horizontal centerline are both in good agreement with the data in literature and the calculated results on uniform meshes. Besides, the velocity vector distributions on various cross sections in lid-driven cavity predicted on non-uniform meshes are compared with those simulated on uniform meshes and those in the literature. All the comparisons and validations show that the 3D lattice Boltzmann model and all the numerical algorithms on non-uniform meshes are accurate and reliable to predict effectively flow fields.

关键词： lattice Boltzmann model interpolation algorithms body-fitted meshes lid-driven cavity flows

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Using Mirror Migration of OBS Data to Image the Deepwater Area of South China Sea

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Journal of Earth Science 2018年第3期29卷 662-668页

作者： Siyou Tong Chuanxi Sun linwei li Dazhen Xu Jie Wang Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of Education Ocean University of China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology

Ocean bottom seismograph （OBS） is widely used in investigating deep crustal structure, which is characterized by a large amount of data information and abundant frequency components because of its multi-component acquisition. OBS is seldom used in deepwater oil and gas exploration and basin research due to the high cost. The complicated seismic wave field is caused by the complex seabed topography, basin and oil and gas structure in deepwater area, which increases the difficulty of image processing. In addition to reflection imaging, we utilize the multiple of OBS data to make accurate imaging and have achieved desirable results in a deep sea area in South China Sea in this paper. Firstly, the original P and Z components of OBS data are processed by wave field separation to obtain the upgoing wave filed and downgoing wave filed. Secondly, its image velocity filed is constructed. Finally, downgoing wave data is used to image （called mirror migration）. Compared with conventional migration, the mirror migration can clearly image the seabed and provide better illumination for shallow layer below the seafloor in the case of sparse nodes, which is proved by the migration results of theoretical and real data in this paper.

关键词： deepwater OBS data mirroring migration wave field separation.

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Estimating submarine groundwater discharge at a subtropical river estuary along the Beibu Gulf,China

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Acta Oceanologica Sinica 2021年第9期40卷 13-22页

作者： Xilong Wang Kaijun Su Juan Du linwei li Yanling Lao Guizhen Ning li Bin Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf Beibu Gulf UniversityQinzhou 535011China Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300192China Key Laboratory of Coastal Science and Engineering Beibu Gulf UniversityQinzhou 535011China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China Research Centre for Eco-Environmental Engineering Dongguan University of TechnologyDongguan 523808China Qinzhou Key Laboratory of Land Resources Use and Monitor Beibu Gulf UniversityQinzhou 535011China

In certain regions,submarine groundwater discharge(SGD)into the ocean plays a significant role in coastal material fluxes and their biogeochemical cycle;therefore,the impact of SGD on the ecosystem cannot be *** this study,SGD was estimated using naturally occurring radium isotopes(^(223)Ra and ^(224)Ra)in a subtropical estuary along the Beibu Gulf,*** results showed that the Ra activities of submarine groundwater were approximately 10 times higher than those of surface *** assuming a steady state and using an Ra mass balance model,the SGD flux in May 2018 was estimated to be 5.98×10^(6) m^(3)/d and 3.60×10^(6) m^(3)/d based on 224Ra and 223Ra,*** the same time,the activities of Ra isotopes fluctuated within a tidal cycle;that is,a lower activity was observed at high tide and a higher activity was seen at low *** on these variations,the average tidal pumping fluxes of SGD were 1.15×10^(6) m^(3)/d and 2.44×10^(6) m^(3)/d with 224Ra and 223Ra,*** SGD accounts for 24%-51%of the total ***,tidal pumping is an important driving force of the SGD in the Dafengjiang River(DFJR)***,the SGD of the DFJR Estuary in the coastal zone contributes significantly to the seawater composition of the Beibu Gulf and the material exchange between land and sea.

关键词： radium isotopes submarine groundwater discharge balance model tidal pumping Dafengjiang River Estuary

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Centrifugal model test on a riverine landslide in the Three Gorges Reservoir induced by rainfall and water level fluctuation

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Geoscience Frontiers 2022年第3期13卷 196-209页

作者： Fasheng Miao Yiping Wu Ákos Török linwei li Yang Xue Faculty of Engineering China University of GeosciencesWuhan 430074China Engineering Research Center of Rock-Soil Drilling&Excavation and Protection Ministry of EducationWuhan 430074China Department of Construction Materials and Engineering Geology Budapest University of Technology and EconomicsBudapestHungary College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Frequent soil landslide events are recorded in the Three Gorges Reservoir area,China,making it necessary to investigate the failure mode of such riverside *** centrifugal test is considered to be the most realistic laboratory model,which can reconstruct the required *** this study,the liangshuijing landslide in the Three Gorgers Reservoir area is selected for a scaled centrifugal model experiment,and a water pump system is employed to retain the rainfall *** the techniques of digital photography and pore water pressure transducers,water level fluctuation is controlled,and multi-physical data are thus obtained,including the pore water pressure,earth pressure,surface displacement and deep *** analysis results indicate that:Three stages were set in the test(waterflooding stage,rainfall stage and drainage stage).Seven transverse cracks with wide of 1–5 mm appeared during the model test,of which 3 cracks at the toe landslide were caused by reservoir water fluctuation,and the cracks at the middle and rear part were caused by *** rainfall process,the maximum displacement of landslide model reaches 3 *** the maximum deformation of the model exceeds 12 cm at the drainage *** failure process of the slope model can be divided into four stages:microcracks appearance and propagation stage,thrust-type failure stage,retrogressive failure stage,and holistic failure *** the thrust-type zone caused by rainfall was connected or even overlapped with the retrogressive failure zone caused by the drainage,the landslide would start,which displayed a typical composite failure *** failure mode and deformation mechanism under the coupling actions of water level fluctuation and rainfall are revealed in the model test,which could appropriately guide for the analysis and evaluation of riverside landslides.

关键词： Riverine landslide The Three Gorges Reservoir Centrifugal model test Rainfall Fluctuation of water level

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Identification and control of Sandwich system with backlash 36

Identification and control of Sandwich system with backlash

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第36届中国控制会议

作者： linwei li Xuemei Ren Minlin Wang Yongfeng Lv School of Automation Beijing Institute of Technology

ISBN: (纸本)9781538629185

The identification and control of Sandwich systems are surveyed for the systems which involve backlash nonlinearity. The focus is made on the way of constructing the identification model and the convergence rate of the identification algorithm. Based on a parameterization of backlash, the Sandwich system with backlash is constructed as a regression model in which the backlash parameter and linear subsystems parameters are separated by using the key-term separation principle. In order to improve the convergence rate, a multi-innovation least squares algorithm is applied to identify the parameter of the regression equation by modifying the scalar single innovation as multi-innovation matrix. Finally, a traditional PID controller achieves a reference signal tracking based on the result of the parameter estimation.

关键词： Multi-innovation identification PID Sandwich system Backlash the key-term separation principle

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Contrasting behaviors of^(210)Po,^(210)Pb and^(234)Th in the East China Sea during a severe red tide:Enhanced scavenging and promoted fractionation

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Acta Oceanologica Sinica 2022年第8期41卷 5-21页

作者： Qiangqiang Zhong linwei li Viena Puigcorbé Dekun Huang Tao Yu Jinzhou Du Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China School of Science Centre for Marine Ecosystems ResearchEdith Cowan UniversityJoondalupWestern Australia 6027Australia

^(210)Po,^(210)Pb,and^(234)Th were determined in water columns of the East China Sea(ECS)to investigate their biogeochemical behaviors during a severe red tide ***^(210)^(210)radionuclides were influenced by particle content effect and particle composition based on distribution coefficient(Kd)*** suspended matter(TSM)content and Kd *** of particulate organic carbon and total suspended matter contents(POC/TSM content ratios).The peaks of mass specific activities of^(210)Po,^(210)Pb,and^(234)Th indicated that degraded particles could have an intensified enrichment ability for radionuclides compared with the surficial suspended *** factor of^(210)Po and^(210)Pb(FPo/Pb)(>1)and fractionation factor of^(210)Po and^(234)Th(FPo/Th)(>1)were much higher at algal blooming regions than that at non-blooming stations,indicating that algal blooms promoted the fractionation of^(210)Po against^(210)Pb and^(234)Th,and proving that^(210)Po exhibited a stronger affinity for biogenic particles than^(210)Pb and^(234)Th when POC content increased in the ***/^(210)Po,POC/^(210)Pb and POC/^(234)Th ratios(content/activity ratios)sharply decreased with depth in both algal bloom and non-bloom *** outbreak of algal bloom promoted the complexity of suspended particles and increased the variability of POC/tracer ratios(content/activity ratios)in the different depth of the shallow *** considerations should be taken to the difficulty of the selection of export interface and the suitable tracers when algal blooming occurs.

关键词： algal blooming East China Sea ^(210)Po ^(210)Pb ^(234)Th biogeochemical behavior

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Study of the Sensitive Properties of Marine Gas Hydrate Based on the Prestack Elastic Inversion

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Journal of Ocean University of China 2019年第5期18卷 1086-1092页

作者： TONG Siyou WANG Jialin li linwei ZHANG Haiqi WU Zhiqiang SHAO Yulan Key Laboratory of Submarine Geosciences and Prospecting Techniques MOEOcean University of ChinaQingdao 266100China Function Laboratory of Marine Geo-Resource Evaluation and Exploration Technology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266200China China Geological Survey Development Research Center Beijing 100037China Qingdao Research Institute of Marine Geology China Geological SurveyQingdao 266071China Shanghai Branch of CNOOC Ltd. Shanghai 200000China

Using a bottom simulating reflector(BSR)on a seismic profile to identify marine gas hydrate is a traditional seismic exploration ***,owing to the abundance differences between the gas hydrate and free gas in different regions,the BSR may be unremarkable on the seismic profile and invisible in certain *** the improvement of exploration precision,difficulty arises in meeting the requirements of distinguishing the abundance differences in the gas hydrate based on ***,we studied other sensitive attributes to ascertain the existence of gas hydrate and its abundance variations,eventually improving the success rate of drilling and *** this paper,we analyzed the contradiction between the seismic profile data and drilling sampling data from the Blake *** extracted different attributes and performed multi-parameter constraint analysis based on the prestack elastic wave impedance ***,we compared the analysis results with the drilling sampling ***,we determined five sensitive attributes that can better indicate the existence of gas hydrate and its abundance *** method overcomes the limitations of recognizing the gas hydrate methods based on BSR or single inversion ***,the conclusions can notably improve the identification accuracy of marine gas hydrate and provide excellent reference significance for the recognition of marine gas ***,the different geological features of reservoirs feature different sensitivities to the prestacking attributes when using the prestack elastic inversion in different areas.

关键词： sensitive seismic attribute the bottom simulating reflector marine gas hydrate prestack elastic impedance inversion multi-parameter constraint analysis

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Top-down method to fabricate TiNi_(1+x)Sn half-Heusler alloy with high thermoelectric performance

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Journal of Materials Science & Technology 2021年第28期87卷 39-45页

作者： Xiong Yang Daquan liu Jianbo li Ruonan Min Huijun Kang li linwei Zongning Chen Enyu Guo Tongmin Wang Key Laboratory of Solidification Control and Digital Preparation Technology(liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China School of Physics and Electronic Information Hulunbeier UniversityInner Mongolia 021008China Ningbo Institute of Dalian University of Technology Ningbo 315000China

The top-down method was used to fabricate the TiNi_(1+x)Sn half-Heusler *** knotty problems have been solved using the top-down method,including the generation of impurity phases,the visible discrepancy in the grain size of the TiNi_(2)Sn second phase,and irregular variations in the Seebeck coefficient(S),electrical conductivity(σ),and thermal conductivity(κ)with increasing Ni *** generation of a large number of incoherent interfaces between the half-Heusler(HH)and full-Heusler(FH)phases fabricated by the top-down method drastically improved and retained κ and S,thereby leading to an enhancement in the dimensionless figure of merit(ZT)by~19%for the TiNi_(1.05)Sn sample as compared to the ZT of the samples prepared by the conventional method.

关键词： n-type TiNi_(1+x)Sn Thermoelectric Thermal conductivity Incoherent interfaces Electrical conductivity

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