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Mapping Sea Level Rise Behavior in an Estuarine Delta System：A Case Study along the Shanghai Coast

Engineering 2018年第1期4卷 156-163页

作者： H.Q. cheng j.Y. chen z.j. chen R.L. Ruan G.Q. Xu G. zeng j.R. zhu z.j. Dai X.Y. chen S.H. Gu X.L. zhang H.M. Wang State Key Laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 China Shanghai Water Planning Design and Research Institute Shanghai 200232 China Shanghai Water Authority Shanghai 200050 China School of Urban and Regional Science East China Normal University Shanghai 200062 China School of Ecological and Environmental Sciences East China Normal University Shanghai 200062 China Shanghai Hydrological Station Shanghai 200232 China Shanghai Municipal Bureau of Urban Planning and Land Resources Shanghai 200003 China Shanghai Institute of Geological Survey Shanghai 200072 China

Sea level rise （SLR） is a major projected threat of climate change that is expected to affect developing coastal cities located in estuarine delta regions, Shanghai is one such city, being located in the Yangtze River Delta （YRD）, It is difficult, however, for decision-makers to implement adaptation due to the uncer- tain causes, magnitudes, and timings of SLR behaviors, This paper attempts to map the causes and mag- nitudes of SLR behaviors on a decadal scale, We analyze the tidal level records from 11 tidal gauge stations and the corresponding bathymetry measurements around these stations since 1921, We identify three new SLR behaviors along the Shanghai coast due to anthropogenic geomorphologic changes （AGCs）, besides the well-known eustatic sea level rise （ESLR）, tectonic subsidence （TS）, and urban land subsidence （ULS）, The first new behavior is regional sea level rise （RSLR）, which occurs as a result of land reclamation and deep waterway regulation, The second is regional sea level fall （RSLF）, which occurs because the channel bed is eroded due to sediment supply decline in the river catchment, The last SLR behavior is local tidal datum rise （LTDR）. Thus, we project that the magnitude of SLR for the Shanghai coast ranges from 10 cm to 16 cm from 2011 to 2030, Clarifying SLR behaviors is important to aid local decision- makers in planning structural and non-structural measures to combat escalating flood damage costs in an estuarine delta system; this field is full of future challenges,

关键词： Sea level rise behavior Anthropogenic geomorphologic change Local tidal datum Flood management Adaptation

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A NOVEL METHOD FOR EVALUATING PLANE STRESS DYNAMIC FRACTURE TOUGHNESS OF 0Cr18Ni10Ti STAINLESS STEEL WELDED jOINTS

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Acta Metallurgica Sinica(English Letters) 2008年第4期21卷 303-312页

作者： z.j. Xu Y.L. Li School of Aeronautics Northwestern Polytechnical University Xi＇an 710072 China

A novel method was proposed for the evaluation of Mode I dynamic fracture toughness （DFT） under plane stress and small scale yielding conditions for welded joints of stainless steel （SS）, 0Cr18Ni10Ti. In a hybrid experimental-numerical approach, the experiments were carried out on the Hopkinson pressure bar apparatus, and three dimensional （3D） transient numerical simulations were performed by a finite element （FE） computer program. Macroscopical plastic deformation was observed at the loading and supporting points, on the specimens, after the test, which could cause a large error if omitted in the numerical simulation. Therefore, elustic-viscoplustic analysis was performed on the specimen by adopting the johnson-Cook （j-C） model to describe the rate-dependent plastic flow behavior of the material. The material heterogeneity in the mismatched welded joints, induced by the difference in the base metal （BM） and the weld metal （WM） in yield stress, has also been taken into consideration by using the j-C models separately. Good accordance was obtained between the experimental and the computational results by the present approach. The relationship between plane stress DFT and loading rate was also obtained on the order of 108 MPa.m^1/2.s^-1.

关键词： 0Cr18Ni10Ti Welded joint High strain rate Dynamic fracture Plane stress

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REAL-TIME FLOOD FORECASTING MODELING OF 1D UNSTEADY CHANNEL FLOW AND KALMAN FILTER

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journal of Hydrodynamics 2001年第1期13卷 64-69页

作者： Li, z.j. Weng, M.H. Coll. of Water Res. and Environ. Hohai Univ. Nanjing 210024 China

The model of 1D unsteady channel flow combined with the Kalman filter for real-time channel flood forecasting was attempted. The suitable upstream and downstream boundary conditions were suggested. The system equation was given by the linearization of the finite difference equations of the mass conservation and momentum equations as well as the boundary conditions. In the Kalman filter updating model, because the number of measurement variable is less than that of state-space variables, the measurement error covariance matrix could be estimated in real time through the innovation sequence, and the system error covariance matrix needs to be estimated preliminarily. A real example of flood forecasting in the Huaihe River was given to explain how the method works. The results show that the model is reasonable and effective.

关键词： Channel flow Computer simulation Kalman filtering Unsteady flow

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An SBFEM-Based Model for Hydraulic Fracturing in Quasi-Brittle Materials

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Acta Mechanica Solida Sinica 2018年第4期31卷 416-432页

作者： F. Yao z.j. Yang Y.j. Hu College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China School of Civil Engineering Shaoxing University Shaoxing 312000 China

A numerical model based on the scaled boundary finite element method is devel- oped to simulate the hydraulic fracturing in concrete-like quasi-brittle materials using cohesive interface elements. The shadow domain method developed previously （Yang and Deeks in Eng Fract Mech 143（4）：333 354, 2007） is extended to consider crack-width-dependent hydraulic pres- sure and cohesive traction, so that the stress intensity factors caused by both crack-face forces are semi-analytically calculated separately in the same way. The crack propagation is determined by the criterion of KI ≥ 0, and the propagation direction by the linear elastic fracture mechanics criteria. Two examples of concrete structures are modeled, and the results are in good agreement with the experimental data and others numerical results.

关键词： Scaled boundary finite element method Hydraulic fracture Cohesive crackmodel Crack propagation

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INVESTIGATION OF LASER BEAM WELDING PROCESS OF Az61 MAGNESIUM-BASED ALLOY

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Acta Metallurgica Sinica(English Letters) 2006年第4期19卷 287-294页

作者： H.Y. Wang z.j. Li Industrial Center Shenzhen Polytechnic Shenzhen 518055 China

Laser welling process of Az61 magnesium alloys is investigated using a special CO2 laser experimental system. The effect of processing parameters including laser power, welling speed, and protection gas flow at the top and bottom is researched. The results show that an ideal well bead can be formed by choosing the processing parameters properly. An optimized parameter range is obtained by a large number of experiments. Among them, laser power and welling speed are the two main parameters that determine the well width and dimensions. The protect gas flow rate has a slight effect on the well width, but it directly effects the surface color of the well. The test results for typical welds indicate that the microhardness and tensile strength of the well zone are better than that of the base metal A fine-grained well region has been observed and no obvious heat-affected zone is found. The well zone mainly consists of small α-Mg phase, （α ＋ Al12Mg17）, and other eutectic phases. The small grains and the eutectic phases in the joint are believed to play an important role in the increase of the strength of wells for Az61 magnesium alloys.

关键词： magnesium alloy laser beam welding laser power welling speed

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Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator

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journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 240-245页

作者： chen jinyou HU Wei School of Automotive Engineering Hunan Financial&Industrial Vocational-technical CollegeHengyang 421002China College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China

To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is *** of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole *** functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of *** experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and *** the voltage reaches 0.8 V,the bending speed of the actuator tends to be ***,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper.

关键词： conductive polymer polypyrrole mechanical characteristics actuators sensing characteristics

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Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong chen Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（zed, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

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Late Paleozoic–Early Mesozoic tectonic evolution of the zongwulong Shan-Qinghai Nanshan tectonic belt in the northern Qaidam continent， northern Tibet

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journal of Earth Science 2025年

作者： Yonghui zhao chen Wu jie Li Peter j.Haproff Lin Ding State Key Laboratory of Tibetan Plateau Earth System and Resources Environment (TPESRE)， Institute of Tibetan Plateau Research， Chinese Academy of Sciences University of Chinese Academy of Sciences Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development， Chongqing University of Science and Technology Department of Earth and Ocean Sciences， University of North Carolina Wilmington

The zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Tibet Plateau experienced a protracted tectonic history， including the openings and closures of the Proto- and Paleo-Tethyan Oceans. Although the tectonic belt has been extensively studied， details regarding the tectonic processes involved in its development remain controversial. To better constrain the tectonic processes of this tectonic belt， we conducted detailed field geological mapping， zircon U-Pb geochronology， and whole-rock geochemical and Sr-Nd isotopic analyses. Our results show that intrusive rocks in the tectonic belt crystallized in ca. 292–233 Ma， perhaps in an arc/subduction setting. Geochemical and Sr-Nd isotopic data suggest that early Permian–late Triassic ultramafic-intermediate intrusions were sourced from the enriched mantle， whereas intermediate-acidic rocks were sourced from mixed crust-mantle. We present the tectonic model that involves: (1) Early Devonian–early Permian intracontinental extension occurred in the northern margin of the Qaidam continent (ca. 416 Ma–292 Ma); (2) Early Permian–late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism (ca. 292 Ma–233 Ma); and (3) subsequent late Triassic intracontinental extension (ca. 233 Ma–215 Ma). Our results suggest that the late Paleozoic–early Mesozoic development of the zongwulong Shan-Qinghai Nanshan was related to the opening， subduction， and slab retreat of the Paleo-Tethyan Ocean， which has key implications for the tectonic evolution of the northern Tibetan Plateau.

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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

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International journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： chen chen Hongyu Xue Qilin Hu Mengfan Wang Pan Shang ziyan Liu Tao Peng Deyang zhang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

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Effect of scanning strategy on grain structure and crystallographic texture of Inconel 718 processed by selective laser melting

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journal of Materials Science & Technology 2018年第10期34卷 1799-1804页

作者： H.Y. Wan z.j. zhou C.P. Li G.F. chen G.P. zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials & Manufacturing Qualification Group Corporate Technology Siemens Ltd. Beijing 100102 China

Two types of scanning strategies were adopted to study the effect of scanning strategy on grain structure and crystallographic texture of selective laser melted （SLM） Inconel 718. The results show that bidirec-tional scanning without and with a 90°-rotation for every layer produced the bimodal grain structure and the directional columnar grain structure, respectively. Controlling the heat flux direction between the successive layers via scanning strategy enabled the formation of such different grain structures. Fur-thermore, when the 90°-rotation was applied, the competitive grain growth mechanism became more pronounced and the strong cube texture developed.

关键词： Selective laser melting Additive manufacturing Scanning strategy Texture Grain structure

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