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Numerical research for contaminant release from un-suspended bottom sediment under different hydrodynamic conditions

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Journal of Hydrodynamics 2013年第4期25卷 620-627页

作者：程鹏达朱红伟樊靖郁费敏锐王道增 School of mechatronical engineering and automation Shanghai University Shanghai Institute of Applied Mathematics and Mechanics Shanghai University

Contaminant release from bottom sediments in rivers is one of the＂ main problems to study the environmental hydrodyna- mics. Contaminant will release into the overlying water column under different hydrodynamic conditions through pore-water in sedi- ment, the release mechanism can be roughly divided into convection diffusion, molecular diffusion and adsorption/desorption. In this article, phosphorus was as a typical contaminant with sorption. Through theoretical analysis of the contaminant release, according to different particle-sized and hydraulic conditions, the mathematics model of contaminant release can be established by the coupled Navier-Stokes equation, Darcy equation, solute transport equation and adsorption/desorption equation. Then that model was verified by flume experiment. Numerical studies show that, under different velocity, the instantaneous concentration of convection diffusion is about 6 times to 50 times larger than that of molecular diffusion during initial stages. The concentration of molecular diffusion is about 1 times to 4 times larger than to that of convection diffusion during late stages. Through analysis, the diffusive boundary layer near the interface can be obtained. In addition, the release will increase with particle size decreasing, and the release will be influe- nced much more by the size change when the particle size is relatively big under different velocity.

关键词： sediment contaminant instantaneous release coupling adsorption/desorption

Plasmonic tandem heterojunctions enable high-efficiency charge transfer for broad spectrum photocatalytic hydrogen production

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Journal of Energy Chemistry 2025年第1期100卷 710-720页

作者： Wenxuan Chen Xiu-Qing Qiao Guo Hui Bojing Sun Dongfang Hou Meidi Wang Xueqian Wu Tao Wu Dong-Sheng Li college of Materials and Chemical engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials China Three Gorges University Hubei Three Gorges Laboratory college of Chemistry and Materials Science and Guangdong Provincial Key Laboratory of Supramolecular Coordination Chemistry Jinan University

Rational engineering of semiconductor photocatalysts for efficient hydrogen production is of great significance but still challenging,primarily due to the limitations in charge transfer ***,a fascinating plasmonic tandem heterojunction with the hc-CdS/Mo2C@C heterostructure is aimfully prepared for effectively promoting the charge separation kinetics of the CdS photocatalyst via the synergistic strategy of phase junction,Schottky junction,and photothermal *** difference in atomic configuration between cubic-CdS （c-CdS） and hexagonal-CdS （h-CdS） leads to effective charge separation through a typical Ⅱ charge transfer mechanism,and plasmonic Schottky junction further extracts the electrons in the hc-CdS phase junction to realize gradient charge ***,the photothermal effect of Mo2C@C helps to expand the light absorption,accelerate charge transfer kinetics,and reduce the hydrogen evolution energy *** carbon layer provides a fast channel for charge transfer and protects the photocatalyst from *** a result,the optimized hc-CMC photocatalyst exhibits a significantly high photocatalytic H2production activity of 28.63 mmol/g/h and apparent quantum efficiency of 61.8%,surpassing most of the reported *** study provides a feasible strategy to enhance the charge transfer kinetics and photocatalytic activity of CdS by constructing plasmonic tandem heterogeneous junctions.

关键词： Heterojunctions LSPR Photocatalyst Phase junction Schottky junction Photothermal effect

Biomass materials for zinc-based sustainable and green energy storage devices:Strategy and mechanism

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Nano Research 2025年第1期18卷 294-314页

作者： Xiaotong Yang Xiaoxin Nie Chenke Tang Yiyang Xiao Qiongguang Li Du Yuan Meng Yao college of Materials Science and engineering Changsha University of Science and TechnologyChangsha 410004China college of Materials Science and engineering Sichuan UniversityChengdu 610065China Anhui Province International Research Center on Advanced Building Materials School of Materials and Chemical EngineeringAnhui Jianzhu UniversityHefei 230601China

As next-generation rechargeable alternatives,zincbased energy storage devices(ZESs)are being intensely explored due to their merits of abundant resource,low cost,safety and environmental ***,ZESs face a succession of critical challenges on pursuing advancing performance,including the stability and kinetics of cathode,stability and transport of zinc electrolyte,reversibility and deep utilization of metallic Zn ***,possessing unique molecular structures with abundant functionals groups,motivates the interdisciplinary field emerging from biomass and aqueous rechargeable *** its high compatibility with ZES design,we here summarize the application of biomass materials in ZESs from the aspects of cathode,electrolyte,membrane/separator and Zn anode,with their corresponding operational mechanisms and attractive functionalities from polymeric ***,the outlooks and perspectives are provided,regarding current challenges and future *** anticipate our minireview paves way on exploring the roles of biomass in aqueous rechargeable batteries.

关键词： zinc biomass materials skeleton/host coating solid-electrolyte interphase(SEI)

High‑Entropy Electrode Materials:Synthesis,Properties and Outlook

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Nano-Micro Letters 2025年第1期17卷 472-506页

作者： Dongxiao Li Chang Liu Shusheng Tao Jieming Cai Biao Zhong Jie Li Wentao Deng Hongshuai Hou Guoqiang Zou Xiaobo Ji college of Chemistry and Chemical engineering Central South UniversityChangsha 410083People’s Republic of China School of Chemistry and Chemical engineering Hunan Institute of EngineeringXiangtan 411104People’s Republic of China

High-entropy materials represent a new category of high-performance materials,first proposed in 2004 and extensively investigated by researchers over the past two *** definition of high-entropy materials has continuously *** the last ten years,the discovery of an increasing number of high-entropy materials has led to significant advancements in their utilization in energy storage,electrocatalysis,and related domains,accompanied by a rise in techniques for fabricating high-entropy electrode ***,the research emphasis has shifted from solely improving the performance of high-entropy materials toward exploring their reaction mechanisms and adopting cleaner preparation ***,the current definition of high-entropy materials remains relatively vague,and the preparation method of high-entropy materials is based on the preparation method of single metal/low-or medium-entropy *** should be noted that not all methods applicable to single metal/low-or medium-entropy materials can be directly applied to high-entropy *** this review,the definition and development of high-entropy materials are briefly ***,the classification of high-entropy electrode materials is presented,followed by a discussion of their applications in energy storage and catalysis from the perspective of synthesis ***,an evaluation of the advantages and disadvantages of various synthesis methods in the production process of different high-entropy materials is provided,along with a proposal for potential future development directions for high-entropy materials.

关键词： High-entropy Energy storage Electrode materials

Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin Luo Hang Li Shan Guo Zhuang Tong Xiaotao Zhou Xu Li Zhaohui Hou Shuquan Liang Guozhao Fang college of Mechanical engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University college of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

Effects of carbon content on the microstructure and tensile properties of a low-density steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang Mingyu Fan Shuyong Jiang Zhongwu Zhang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Metal Material for Marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

Carbon can change the phase components of low-density steels and influence the mechanical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** microstructural changes and mechanical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(C-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while Mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)C carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening mechanisms work hardening behavior

Dynamic behaviors of graphene platelets-reinforced metal foam piezoelectric beams with velocity feedback control

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 63-80页

作者： Jie CHEN Xinyue ZHANG Mingyang FAN School of Mathematics Statistics and Mechanics Beijing University of Technology college of Mechanical & Energy engineering Beijing University of Technology

Graphene platelets(GPLs)-reinforced metal foam structures enhance the mechanical properties while maintaining the lightweight characteristics of metal foams. Further bonding piezoelectric actuator and sensor layers on the surfaces of GPLs-reinforced metal foam beams enables active vibration control, greatly expanding their applications in the aerospace industry. For the first time, this paper investigates the vibration characteristics and active vibration control of GPLs-reinforced metal foam beams with surfacebonded piezoelectric layers. The constant velocity feedback scheme is used to design the closed-loop controller including piezoelectric actuators and sensors. The effects of the GPLs on the linear and nonlinear free vibrations of the beams are numerically *** Newmark-β method combined with Newton's iteration technique is used to calculate the nonlinear responses of the beams under different load forms including harmonic loads,impact loads, and moving loads. Additionally, special attention is given to the vibration reduction performance of the velocity feedback control on the responses of the beam.

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Parametric adaptive time-frequency representation based on time-sheared Gabor atoms

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Journal of Systems engineering and Electronics 2007年第1期18卷 1-7页

作者： Ma Shiwei Zhu Xiaojin Chen Guanghua Wang Jian Cao Jialin School of mechatronical engineering & automation Shanghai Key Lab of Power Station Automation Technology Shanghai Univ. Shanghai 200072 E R. China

A localized parametric time-sheared Gabor atom is derived by convolving a linear frequency modulated factor, modulating in frequency and translating in time to a dilated Gaussian function, which is the generalization of Gabor atom and is more delicate for matching most of the signals encountered in practice, especially for those having frequency dispersion characteristics. The time-frequency distribution of this atom concentrates in its time center and frequency center along energy curve, with the curve being oblique to a certain extent along the time axis. A novel parametric adaptive time-frequency distribution based on a set of the derived atoms is then proposed using a adaptive signal subspace decomposition method in frequency domain, which is non-negative time-frequency energy distribution and free of cross-term interference for multicomponent signals. The results of numerical simulation manifest the effectiveness of the approach in time-frequency representation and signal de-noising processing.

关键词： Time-frequency analysis Gabor atom Time-shear Adaptive signal decomposition Time-frequency distribution.

Synthesis and antitumor activities of rare earth substituted phosphotungstates containing 5-fluorouracil

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Journal of Rare Earths 2012年第5期30卷 467-472页

作者：冯长根甘强刘霞何洪优 School of mechatronical engineering Beijing Institute of Technology college of Science China Agricultural University

Two novel rare earth substituted phosphotungstates containing 5-fluorouracil,K 9（C 4 H 4 FN 2 O 2） 2 Nd（PW 11 O 39） 2 ·25H 2 O（FNdPW） and K 9（C 4 H 4 FN 2 O 2） 2 Ce（PW 11 O 39） 2 ·23H 2 O（FCePW）,were synthesized and characterized by elementary analysis,FT-IR spectra,X-ray powder diffraction and 1 H *** thermal analysis showed that FNdPW decomposed at 210 and 493 oC,and FCePW decomposed at 223 and 471 oC,both of which had good thermal *** tests were performed to study the antitumor activities against HeLa cells and HepG-2 cells of FNdPW,FCePW,5-fluorouracil,C 4 H 4 FN 2 O 2 H 2 PW 12 O 40 ·8H 2 O and K 11 Ln（PW 11 O 39） 2 ·xH 2 O（Ln=Nd,Ce）,and their cytotoxicities against HEK 293 *** results showed that FNdPW and FCePW possessed higher antitumor activities and lower cytotoxicities than those of 5-fluorouracil and C 4 H 4 FN 2 O 2 H 2 PW 12 O 40 ·8H 2 O,of which FNdPW exhibited the highest antitumor activates against HeLa cells（EC 50 =3.41×10-6 mol/L） and HepG-2 cells（EC 50 =6.24×10-6 mol/L）.Thus the introduction of rare earth elements and 5-fluorouracil could significantly enhance antitumor effect of polyoxometalates.

关键词： phosphotungstates 5-fluorouracil rare earth HeLa HepG-2 antitumor cytotoxicity