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Journal of Hydrodynamics 2001年第4期13卷 14-23页

作者： wang chao {2. of water Resources and environment, hohai university, nanjing 2.0098, china college of water Resources and {2. Hohai University

water quality is the key problem of the East-Line Project of water Transfer from South to North{2.. In this paper, the principles of a 1D and 2.-integrated mathematical model for describing the dynamics of water in a flow-through river, canals and lakes was worked out. The numerical method and model algorithm were developed. The efficiency of the model was estimated by applying it to studying water dynamics in the Luomahu reservoir and simulating the spreading process of a polluted water mass and the evolution of the concentration. The results of calculations are used to assess water environmental quality and to manage water resource in the Luomahu reservoir and the Jinghang-Canal for the Project of water Transfer from South to North{2..

关键词： mathematical model integral stream function water quality water Transfer from South to North Project

EFFECTS OF SUBMERGED MACROPHYTES ON SEDIMENT SUSPENSION AND NH_4-N RELEASE UNDER HYDRODYNAMIC CONDITIONS

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Journal of Hydrodynamics 2010年第6期22卷 810-815页

作者： wang chao wang Cun wang Ze Key Laboratory of Integrated Regulation and Resource Department on Shallow Lakes Ministry of EducationHohai University Nanjing 210098 China State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering Hohai University Nanjing210098 China college of Mechanics and Materials Hohai University Nanjing 210098 China

Aquatic vegetation affects sediment suspension and nutrient release by changing the flow structure. Experiments on the influence of submerged vegetation on flow structure, sediment suspension, and NH4-N release were carried in a flume with natural submerged vegetation. Turbulence characteristics in the vegetation section were measured using a three-dimensional acoustic Doppler velocimeter. The effects of submerged vegetation on bed shear stress （ τb ）, sediment suspension, and NH4-N release were analyzed. Results show that with vegetation, bed shear stress is reduced by about 2.% - 80%, which, in turn, reduces sediment suspension. The impact of submerged vegetation on sediment suspension and NH4-N release should be considered along with flow intensity. When the flow Reynolds number is relatively small, the submerged vegetation is quite capable of inhibiting sediment suspension and reducing NH4-N release, but when the Reynolds number reaches a certain value, the presence of aquatic plants exacerbates sediment suspension and promotes NH4-N release. Results also reveal that a highly significant positive correlation exists between NH4-N concentration and water turbidity in both vegetated and non-vegetated channels.

关键词： sediment suspension submerged macrophytes turbulence behavior bed shear stress turbidity

THE ALGORITHMS AND APPLICATIONS FOR DETERMINING PERMEABILITY COEFFICIENTS BY PULSE SPECTRUM TECHNIQUE

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Journal of Hydrodynamics 2002年第2期14卷 112-115页

作者： wang Ling-ling college of {2. Conservancy and Hydropower Engineering, hohai university, nanjing 2.0098, china college of water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The determination of inhomogeneous permeability coefficient was studied as a parameter-control inverse problem for parabolic-type equation in this paper. By virtue of PST, the solution of the inverse problem is converted into an iteration procedure of solving a direct problem and solving a Fredholm integral equation of the first kind. Besides, Tikhonov normalization method is introduced to treat the uncertainty caused by the integral equation. Thus an algorithm for determining inhomogeneous permeability coefficient has been formulated and implemented. Numerical results show: (1) The algorithm presented in the paper is suitable to strongly inhomogeneous seepagel; (2. The additional information needed for solution is merely the seepage velocity on partical boundary, so that drill works can be reduced remarkably; (3) The algorithm is applicable to determining inhomogeneous transmission coefficients in groundwater engineering or other engineering.

关键词： inverse problem Pulse Spectrum Technique (PST) permeability coefficient parameter identification

Microstructure and property of laser additive manufactured alloy Ti-6Al-2.-1.5Mo-0.5Zr-0.3Si after aged at different temperatures

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Rare Metals 2024年第5期43卷 2275-2281页

作者： Guo-chao Li Xu Cheng Hua-Ming wang National Engineering Laboratory of Additive Manufacturing for Large Metallic Components and Engineering Research Center of Ministry of Education on Laser Direct Manufacturing for Large Metallic Components School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

The solid solution and aging treatment for conventional manufacturing processes might not be suitable for laser additive manufactured titanium alloys due to the different lamellar *** this study,the influence of aging temperatures(600,700 and 800°C)on microstructure and mechanical properties of titanium alloy Ti-6Al-2.-1.5Mo-0.5Zr-0.3Si was *** results indicate that after solid solution treatment at 970°C followed by water quenching,the alloy mainly consists of coarsening lamellar a phase in martensite α' *** at 600°C will not change the size of primary lamellar α phase but lead to huge amount of secondary a phases(α_(s))generating with very fine *** increasing the aging temperature,the number of α_(s) decreases but with coarsened *** aged at 800°C,the width of the asphase reaches 350 nm,almost 7 times wider than that aged at 600°*** changing size of α_(s) obviously influences the property of the *** fine α_(s) leads to high strength and microhardness but low plasticity,and specimen aged at 700°C with suitable assize has the best comprehensive properties.

关键词： α+βtitanium alloy Laser additive manufacturing Solid solution and aging treatment Microstructure Room temperature tensile property

Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

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Journal of Iron and Steel Research International 2024年第3期31卷 531-551页

作者： Jing-feng wang Lin-zhu wang {2.-yi Chen Xiang wang Fei Zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Zhengzhou Railway Vocational and Technical college Zhengzhou 450000HenanChina Guizhou Provincial university Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue *** earth was usually added to modify the carbides and *** existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was *** precipitation mechanism and nucleation of primary carbides with rare earth were *** position and form of rare earth in steel and their effects on alloying elements segregation were *** addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were *** on the current references,it can be known that adding rare earth facilitated refined and dispersed primary *** size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic ***,the number of primary carbides at grain boundaries would be significantly ***,rare earth had little impact on thermal *** nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary *** earth had been reported to affect the mechanism and process of primary carbide ***,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by ***,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation Dendritic structure

Cascade electrolysis and thermocatalysis: a reliable system for upgrading C1 to C4 hydrocarbons

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Rare Metals 2024年第1期43卷 410-412页

作者： chao-Yue Sun Wen Li Hai-Qing wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China

The carbon cycle is important for maintaining a stable climate and carbon balance on Earth. Renewable-electricitydriven upcycling of carbon dioxide (CO_(2.) into value-added multi-carbon molecules is a potentially sus... 详细信息

关键词： cycling hydrocarbons enable

CHANGES OF PAN EVAPORATION IN THE UPPER REACH OF THE YANGTZE RIVER

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Journal of Hydrodynamics 2011年第4期23卷 503-509页

作者： RONG Yan-shu wang Wen JIANG Hai-yan college of Hydrology and water Resources Hohai University Nanjing 210098 China State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China

The upper reach of the Yangtze River, 4 511 km long from west to east, contains a great amount of water resources of the Yangtze River Basin. This article studies the characteristics of the pan evaporation, the related meteorological variables, and their effects on the pan evaporation, based on the data of the daily pan evaporation （1980-2.08） and other meteorological variables （1961-2.08）. The results show that the linear trend of the pan evaporation has remarkable regional features, i.e., the decrease trend in the southwest and the increase trend in the northeast of the investigated region, and the Yangtze River is approximately the boundary of these trends. The meteorological variables have different effects on the pan evaporation depending on the fact that they are in the category the thermal variables or the dynamic variables. The thermal meteorological variables （i.e., air temperature, diurnal temperature range, and sunshine duration） have positive partial correlations with the pan evaporation, while the dynamic ones （air pressure, rainfall, and relateive humidity） have negative correlations with the pan evaporation. The correlation of the wind speed remains to be investigated.

关键词： linear time trend meteorological variable pan evaporation partial correlation Yangtze River

Research progress on catalysts for organic sulfur hydrolysis: Review of activity and stability

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Chinese Journal of Chemical Engineering 2024年第7期71卷 203-216页

作者： Bingning wang Xianzhe wang Song Yang {2. Yang Huiling Fan Ju Shangguan State Key Laboratory of Clean and Efficient Coal Utilization Taiyuan University of TechnologyTaiyuan 030024China Shanxi Engineering Center of Civil Clean Fuel Taiyuan University of TechnologyTaiyuan 030024China college of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China college of environmental Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

The removal of organic sulfur through catalytic hydrolysis is a significant area of research in the field of *** review provides an overview of recent advancements in catalytic hydrolysis technology of organic sulfur,including the activity,stability,and atmosphere effects of hydrolysis *** emphasis is on strategies for enhancing hydrolysis activity and anti-oxygen poisoning property of *** modification,metal doping and nitrogen doping have been found to improve the activity of *** components modification is the most commonly used method,the formation of oxygen vacancies through metal doping and creation of nitrogen basic sites through nitrogen doping also contribute to the hydrolysis of organic *** strategies for anti-oxygen poisoning are discussed in a systematic *** structural regulation of catalysts is beneficial for the desorption and diffusion of hydrogen sulfide(H_(2.S),thereby effectively inhibiting its *** doping and the addition of electronic promoters such as transition metals can protect active sites and decrease the number of active oxygen *** methods have been proven to enhance the anti-poisoning performance of ***,this article summarizes how different atmospheres affect the activity of hydrolysis *** objective of this review is to pave the way for the development of efficient,stable and widely used catalysts for organic sulfur hydrolysis.

关键词： Organic sulfur Hydrolysis Catalysts Activity Stability

Topology optimization of chiral metamaterials with application to underwater sound insulation

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1119-1138页

作者： chao wang Honggang ZHAO Yang wang Jie ZHONG Dianlong YU Jihong WEN Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha410073China

Chiral metamaterials have been proven to possess many appealing mechanical phenomena,such as negative Poisson's ratio,high-impact resistance,and energy *** work extends the applications of chiral metamaterials to underwater sound *** chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization *** acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss(STL),while proper stiffness guarantees its robust acoustic performance under a hydrostatic *** proof-of-concept demonstrations,two specimens are fabricated and tested in a water-filled impedance *** results show that,on average,over 95%incident sound energy can be isolated by the specimens in a broad frequency range from 1 k Hz to 5 k Hz,while the sound insulation performance keeps stable under a certain hydrostatic *** work may provide new insights for chiral metamaterials into the underwater applications with sound insulation.

关键词： chiral metamaterial topology optimization underwater sound insulation low acoustic impedance sound transmission loss(STL)

EXPERIMENT OF IMPACT OF RIVER HYDRAULIC CHARACTERISTICS ON NUTRIENTS PURIFICATION COEFFICIENT

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Journal of Hydrodynamics 2007年第3期19卷 387-393页

作者： wang Pei-fang wang Xiao-rong wang chao State Key Laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing 210093 China State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Key Laboratory of Intergrated Regulation and Resource Development on Shallow Lakes College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Hydraulic characteristics of a river are the key factors for river water quality improvement and river restoration. A simulated river was exploited to study the interactions between water contaminant purification coefficients and the characteristics of the river, such as the cross-section velocity, water depth, Reynolds number, and Froude number. To enhance the purification capacity of the river, detritus with 5 mm to 10 mm in diameter and contact surface area per volume of 87.6 m^2.m^3 were constructed naturally at the bed and along one side of the bank to form half shape of the river cross-section. During the one-month experiment （including 3 periods） from the third of November to the fourth of December, 2.05, three categories of hydraulic conditions were investigated. Results show that the purification coefficient （K） of Total Nitrogen （TN） is closely coherent with the hydraulic retention time （T）, river length （L）, Reynolds number （Re） and Froude number （Fr）. The relationship of K and T generally agrees with the power law under the three experimental water hydraulic conditions. Based on these results, the optimal Re and Fr ranges can be obtain to serve as a guideline for ecological re-engineering design to improve river water quality and restore river ecosystem.

关键词： Hydraulic characteristics total nitrogen,purification coefficient interaction simulated river