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Seabed deposition and erosion change and influence factors in the Yangshan Deepwater Port over the years

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Acta Oceanologica Sinica 2019年第7期38卷 96-106页

作者： Shuhua Zuo Hualiang Xie Xiaoming Ying Cheng Cui Yuxin Huang Huaiyuan Li Mingxiao Xie National Engineering laboratory for Port Hydraulic Construction Technology Tianjin Research Institute for Water Transport EngineeringTianjin 300456China Key laboratory of Engineering Sediment of Ministry of transport Tianjin Research Institute for Water Transport EngineeringTianjin 300456China South China Sea Institute of Marine Planning and Environmental Research State Oceanic AdministrationGuangzhou 510300China

The seabed scouring and silting are very important to the construction of port and waterway engineering. Seabed deposition and erosion change is complicated due to the influence of sediment supply, human activities and other factors. The Yangshan Deepwater Port is the new deep water harbor, which is an important part of the Shanghai International Shipping Service Center. Its construction has received much attention. At present, the water depth from the 1 st to the 3 rd harbor district is currently suitable under regular dredging and tidal current action. The fourth harbor district will be built in the world’s largest fully-automated deep water wharf. In the study, bathymetry change of the entire sea area of the Yangshan Deepwater Port and the 4 th harbor district(i.e.,phase IV project) waters were analyzed quantitatively using multiyear bathymetric, hydrological and sediment data. The results show that from 1998 to 2010, seabed changes are characterized by large volumes of erosion and sedimentation, which the southern part was deposited and the northern part was eroded in the inner harbor waters, but the seabed of the Kezhushan inlet was eroded. Seabed changes of phase IV project waters generally show a scour tendency in recent few years with the annual scour rate about 0.7 m. Among the many factors, the existence of Kezhushan inlet and its influence of the western water flow play an important positive role in water depth changes under the ebb tide action.

关键词： Yangshan Deepwater Port phase IV project water and sediment environment seabed deposition and erosion change diversion dike

Two-fluid modeling of Geldart A particles in gas-solid micro-fluidized beds

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Particuology 2015年第4期13卷 118-127页

作者： Xiaoxing Liu Chuanqiang Zhu Shujun Geng Meiqin Yao Jinhui Zhan Guangwen Xu State Key laboratory of Multi-phase Complex System Institute of Process Engineering Chinese Academy of Science Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

The fiuidization behavior of Geldart A particles in a gas-solid micro-fluidized bed was investigated by Eulerian-Eulerian numerical simulation. The commonly used Gidaspow drag model was tested first. The simulation showed that the predicted minimum bubbling velocities were significantly lower than the experimental data even when an extremely fine grid size （of approximately one particle diameter） was used. The modified Gibilaro drag model was therefore tested next. The predicted minimum bubbling velocity and bed voidage were in reasonable agreement with the experimental data available in literature. The experimentally observed regime transition phenomena from bubbling to slugging were also reproduced successfully in the simulations. Parametric studies indicated that the solid-wall boundary conditions had a significant impact on the predicted gas and solid flow behavior.

关键词： Micro-fluidized bed Geldart A particle Two-fluid model Boundary condition Drag model

Dust Aerosol Effects on Cirrus and Altocumulus Clouds in Northwest China

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Journal of Meteorological Research 2015年第5期29卷 793-805页

作者：王文彩盛立芳金宏春韩永清 Physical Oceanography laboratory Ocean University of China Key laboratory for Semi-Arid Climate change of the Ministry of Education College of Atmospheric SciencesLanzhou University Shandong Provincial Meteorological Bureau

Dust aerosol effects on the properties of cirrus and altocumulus cloud in Northwest China were studied for the period March-May 2007 by using the satellite data of Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations （CALIPSO）, Aqua, and CloudSat. Dusty clouds were defined as those mixed with dust aerosols or existing in dust aerosol conditions, while pure clouds were those in a dust-free environment. For dusty altocumulus clouds, the mean values of cloud optical depth （OPD）, cloud liquid water path （LWP）, cloud ice water path （IWP）, cloud effective particle radius （Re）, and cloud effective particle diameter （Dr） were 6.40, 40.23 g m-2, 100.70 g m-2, 8.76 μm, and 40.72 μm, respectively. For pure altocumulus clouds, the corresponding mean values were 9.28, 76.70 g m-2, 128.75 g m-2, 14.03 μm, and 48.92 μm, respectively. These results show a significant decrease of OPD, LWP, IWP, Re, and De of approximately 31%, 48%, 22%, 38%, and 17% because of the effects of dust aerosols. Moreover, the effects of dust aerosols on liquid-phase altocumulus clouds were greater than on ice-phase altocumulus clouds. Regarding dusty cirrus clouds, the mean values of OPD, IWP, and De were 5.11, 137.53 g in 2, and 60.44 μm, respectively. In contrast, the mean values were 6.69, 156.17 g m-2, and 66.63 μm, respectively, for pure cirrus clouds, with a 24% decrease in OPD, a 12% decrease in IWP, and a 9% decrease in De. These results indicate that dust aerosols can significantly change cloud properties, leading to a reduction of OPD, LWP, and effective particle size for both altocumulus and cirrus clouds in Northwest China.

关键词： dusty cloud aerosol-cloud interaction altocumulus cloud cirrus cloud

Local proton hopping mechanism in imidazolium-based plastic crystal:an ab initio molecular dynamics study

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Communications in Theoretical Physics 2022年第4期74卷 91-96页

作者： Bohai Zhang Yike Huang Jiangshui Luo Ailin Li Tianying Yan School of Materials Science and Engineering Nankai UniversityTianjin 300350China Lab of Electrolytes and phase change Materials College of Materials Science and EngineeringSichuan UniversityChengdu 610065China College of Science Civil Aviation University of ChinaTianjin 300300China

Protic organic ionic plastic crystals(POIPCs)are promising solid-state proton conductor materials in anhydrous proton exchange membrane fuel cells,due to their mechanical flexibility and high ionic conductivity in the plastic crystal *** typical POIPCs,the ions are orientationally disordered while the centers of mass are ordered(positional order)like the crystal *** local disorder provides more degrees of freedom for the translational and rotational diffusion of ions,thus enhancing proton conduction either via the vehicle mechanism or the Grotthuss *** the local dynamics and the interactions of the cations and anions during the proton transfer process are far from being fully ***,we performed Car–Parrinello molecular dynamics(CPMD)simulation on the imidazolium methanesulfate([ImH][CH_(3)SO_(3)])unit *** artificially creating one proton hole,we found that a proton can hop directly between the *** the anion is not directly involved in proton hopping,the oxygen atom in the sulfonate group interacts with the proton and has a synergetic motion along with the proton hopping *** indicates the structural disorder of imidazolium rings and the aid of an anion can facilitate Grotthuss-type proton hopping in imidazolium-based POIPCs.

关键词： plastic crystal proton transfer grotthuss mechanism negative correlation

Molecular dynamics simulation for surface melting and self-preservation effect of methane hydrate

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Science China Chemistry 2008年第7期51卷 651-660页

作者： DING LiYing GENG ChunYu ZHAO YueHong HE XianFeng WEN Hao Key laboratory of Multi-phase Reaction Institute of Process EngineeringChinese Academy of SciencesBeijing 100080China Graduate University of Chinese Academy of Sciences Beijing 100049China

The surface melting process of structure sI methane hydrate is simulated at T = 240, 260, 280, and 300 K using NVT molecular dynamics method. The simulation results show that a quasi-liquid layer will be formed during the melting process. The density distribution, translation, orientation, and dynamic properties of water molecules in the quasi-liquid layer are calculated as a function of the distance normal to the interface, which indicates the performance of quasi-liquid layer exhibits a continuous change from crystal-like to liquid-like. The quasi-liquid layer plays as a resistance of mass transfer restraining the diffusion of water and methane molecules during the melting process. The resistance of quasi-liquid layer will restrain methane molecules diffuse from hydrate phase to gas phase and slow the melting process, which can be considered as a possible mechanism of self-preservation effect. The performance of quasi-liquid layer is more crystal-like when the temperature is lower than the melt- ing-point of water, which will exhibit an obvious self-preservation. The self-preservation will weaken while the temperature is higher than the melting-point of water because of the liquid-like performance of the quasi-liquid layer.

关键词： gas hydrate surface melting self-preservation effect molecular dynamics

Disorder Induced Dynamic Equilibrium Localization and Random phase Steps of Bose–Einstein Condensates

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Chinese Physics Letters 2011年第10期28卷 5-8页

作者： DUAN Ya-Fan XU Zhen QIAN Jun SUN Jian-Fang JIANG Bo-Nan HONG Tao Key laboratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Center for Macroscopic Quantum phenomena Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201203

We numerically analyze the dynamic behavior of Bose–Einstein condensate(BEC)in a one-dimensional disordered potential before it completely loses spatial quantum *** find that both the disorder statistics and the atom interactions produce remarkable effects on *** also find that the single phase of the initial condensate is broken into many small pieces while the system approaches localization,showing a counter-intuitive step-wise phase but not a thoroughly randomized *** the condensates as a whole show less flow and expansion,the currents between adjacent phase steps retain strong time *** we show explicitly that the localization of a finite size Bose–Einstein condensate is a dynamic equilibrium state.

关键词： Einstein steps intuitive

A NOVEL phase CONTROL TECHNIQUE FOR INJECTION LOCKED OSCILLATORS

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Journal of Electronics(China) 1995年第4期12卷 374-377页

作者： Kwok-Wai Wong Albert K. Y. Lai 曾学刚 Department of Electronic Engineering the Chinese University of Hong Kong Shatin Hong Kong University of Electronic Science and Technology of China Chengdu 610054 A novel technique to obtain injection locked oscillators phase tuning beyond 180°is demonstrated. The idea is to cascade injection locked oscillators together for phase change accumulation. A two stage injection locked oscillators can theoretically provide a maximum of 360?phase change within the locking range. This is particularly useful for phased array antenna applications.

A novel technique to obtain injection locked oscillators phase tuning beyond 180° is demonstrated. The idea is to cascade injection locked oscillators together for phase change accumulation. A two stage injection locked oscillators can theoretically provide a maximum of 360?phase change within the locking range. This is particularly useful for phased array antenna applications.

关键词： phase control Locking Oscillators Antenna array

Direct observation of spreading precursor liquids in a corner

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National Science Review 2023年第7期10卷 196-202页

作者： Weining Miao Shihao Tian Quanzi Yuan Ye Tian Lei Jiang Key laboratory of Bioinspired Smart interfacial Science Technical Institute of Physics and Chemistry Chinese Academy of Sciences School of Future Technology University of Chinese Academy of Sciences State Key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences

Precursor liquid is a nanoscale liquid creeping ahead of the macroscopic edge of spreading liquids,whose behaviors tightly correlate with the three-phase reaction efficiency and patterning ***,the important spatial-temporal characteristic of the precursor liquid still remains obscure because its real-time spreading process has not been directly ***,we report that the spreading ionic liquid precursors in a silicon corner can be directly captured on video using in situ scanning electron *** situ spreading videos show that the precursor liquid spreads linearly over time(ΔL～ΔT) rather than obeying the classic Lucas-Washburn law(l～t1/2) and possesses a characteristic width of ～250-310 *** analyses and molecular dynamics simulations demonstrate that the unique behaviors of precursor liquids originate from the competing effect of van der Waals force and surface *** findings provide avenues for directly observing liquid/solid interfacial phenomena on a microscopic level.

关键词： precursor liquid spreading spatial–temporal characteristic direct observation corner ionic liquids

Metal-organic framework-derived CoP_(2)@N-doped carbon hollow spheres for efficient oxygen evolution reaction

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Journal of Materials Science & Technology 2023年第33期164卷 240-245页

作者： Wei Zhang Jiangshui Luo Xuan Zhang Wei Guo Ning Han Sijie Xie Zhenyu Zhou Zahid Anwer Zhenhong Xue Jan Fransaer Department of Materials Engineering KU LeuvenLeuven 3001Belgium Lab of Electrolytes and phase change Materials College of Materials Science and EngineeringSichuan UniversityChengdu 610065China ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China

*** is considered as a viable alternative to fossil fuels[1,2].Large-scale hydrogen production by electrochemical water splitting is regarded as an important *** consists of two half-reactions:hydrogen evolution reaction(HER)at the cathode and oxygen evolution reaction(OER)at the anode[3].Compared to the HER,the OER has sluggish kinetic and large overpotentials,re-sulting from the complex oxidation pathway[4,5].Although RuO_(2) and IrO_(2) have excellent catalytic OER performance[6],their large-scale deployment is unfeasible due to the scarcity and high cost of these noble metal ***,cheap OER electrocatalysts have been actively investigated[7].

关键词： spheres splitting noble