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The numerical simulation of the movements and thermal states of atomized metal droplets in the spray forming process

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Baosteel Technical Research 2009年第2期3卷 58-63页

作者： YUAN Feng FAN Junfei REN Sanbing le hairong ZHAO Shunli Advanced Technology Division Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

Numerical simulation was performed in an atomizing chamber to investigate the movements and thermal states of the atomized metal droplets in the spray forming process. The velocity, temperature and solid fractions of metal droplets with different diameters and under different atomizing pressures were investigated. The results indicate that a higher atomizing pressure results in the increased flying velocity of the metal droplets and a decrease in the cone-shaped angle formed by their flight paths. Synchronously, the cooling of the metal droplets is accelerated and the time of the complete solidification process is shortened. Under the same atomization pressure, large metal droplets have a lower flying speed and a lower rate of temperature decrease in the atomizing chamber than small metal droplets. In addition, metal droplets flying along the edge of the atomizing region cool faster than those flying in the core region.

关键词： spray forming atomization pressure atomized metal droplet diameter numerical simulation

Microstructure of the spray formed Vanadis4 cold work die steel and its evolution during hot rolling and heat treatment

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Baosteel Technical Research 2011年第3期5卷 20-27页

作者： SHI Haisheng YAN Fei FAN Junfei le hairong JIN Bingzhong Advanced Technology Division Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Cold-rolling Plant Wuhan Iron and Steel Co. Ltd. Wuhan 430083 China

A high alloyed Vanadis4 （V4） steel was produced by spray forming process in Baosteel, and the microstructure of the as-sprayed steel and its evolution during hot rolling and annealing processes were characterized. It was found that the as-sprayed V4 steel has a homogeneous and fine scale rrficrostructure with uniform dispersion of carbides. The hot rolling temperature is the key factor in controlling the evolution of type, morphology and distribution of carbides, as well as the matrix microstructure of the as-rolled steels. The optimized processing parameters for the as-sprayed V4 steel are rolling at 1050℃ and then annealing at 900℃. The microstructural evolution mechanisms during hot rolling and annealing are determined according to the microstructural analyasis of the material at different stages.

关键词： spray forming Vanadis4 steel microstructure evolution

Microstructure characteristics of spray-formed high vanadium and cobalt high speed steel

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Baosteel Technical Research 2011年第3期5卷 28-32页

作者： ZHOU Candong le hairong FAN JunFei REN Sanbing ZHAO Shunli Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200940China Advanced Technology Division Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

The microstructure of high vanadium and cobalt high speed steel （high-V/Co HSS ） and the morphology of its carbides were analyzed by optical microscope （OM）,scanning electron microscope （SEM） ,electron probe microanalysis （EPMA）, X-ray power diffraction （XRD）, atomic force microscopy （AFM） and single phase erosion （SPE）. The results suggest that the as-sprayed high-V/Co HSS has fine equiaxed grains （about 20 μm in size）, which were homogeneously distributed. The carbides have two classical morphologies- one is fine particles （ about 2 μm in size） distributed along the grain boundaries and the other is needle-like one, distributed on the grain boundaries. There are MC carbides, M2C carbides,M6C carbides and Cr2WC2 carbides in the as-sprayed high-V/Co HSS samples,however,in the as-cast high-V/ Co HSS ,there are MC carbides and CrzWC2 carbides only. The SPE results show that there are two types of MC carbides in the as-sprayed HSS ：the sphere one and the particle-like one. The former is about 2 ixm in size and the latter is less than 1 μm, dispersed inside the grains,quite different from the MC carbides in the as-cast HSS. According to the AFM results, the skeleton-like M6C carbides of the as-sprayed high-V/Co HSS are embedded in the matrix along the grain boundaries. It is found that there are sharp membrane pieces on the carbides. Some small bamboo-shoot-like MC carbides grow from the matrix and are dispersed inside the grain. Those larger MC carbides are spherical particles embedded at the grain boundary junctions.

关键词： high-V/Co HSS microstructure carbides

Impacts of electrochemical disinfection on the viability and structure of the microbiome in secondary effluent water

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 73-83页

作者： Marvin Yeung Lan Tian Yuhong Liu hairong Wang Jinying Xi Environmental Simulation and Pollution Control State Key Joint Laboratory School of EnvironmentTsinghua UniversityBeijing100084China Graduate School at Shenzhen Tsinghua UniversityShenzhen518055China

Electrochemical disinfection(ECD)is a promising disinfection technique for wastewater reclamation;however,the impacts of ECD on the microbiome in secondary effluent wastewater remain *** this study,Propidium monoazide-qPCR(PMA-qPCR)and the plate count method were used to evaluate the inactivation performance,and the PMA-16S rRNA gene sequences of living cells were targeted to study the microbiome.A discrepancy was found between PMA-qPCR and the plate count method in the evaluation of cell count,with increases of 1.5 to 2.2 orders of magnitude in the disinfection rate after 150 s of ***,the cell count recovered and occasionally exceeded original levels within 3 d after *** was suppressed after ECD,but the microbiome after 150 s disinfection retained a higher level of evenness and stability in the community with a median Shannon index(>3.7).Pathogenic bacteria remained high in relative abundance even after 150 s of 25 V disinfection,but the biofilm-forming population was effectively suppressed by *** co-occurrence network revealed a centralized and fragile network as disinfection persisted,demonstrating the destabilizing effects of ECD on the *** pathways for cell membrane synthesis and organic compound degradation were enriched after *** reaction of the microbiome after ECD was similar to other disinfection techniques in terms of community structure.

关键词： Electrochemical disinfection Secondary effluent Microbiome

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： hairong Wang Beijing Zhou Lisi Zhang He Ma School of Computer Science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovielens-1M,Movielens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

Data and Model Driven Task Offloading Strategy in the Dynamic Mobile Edge Computing System

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Journal of Systems Science & Complexity 2024年第1期37卷 351-368页

作者： DONG hairong WU Wei SONG Haifeng LIU Zhen ZHANG Zixuan School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Electronic and Information Engineering BeiHang UniversityBeijing 100191China CRSC Research&Design Institute Group Co. Ltd.Beijing 100070China

Mobile Edge Computing(MEC)provides communication and computational capabilities for the industrial Internet,meeting the demands of latency-sensitive ***,traditional model-driven task offloading strategies face challenges in adapting to situations with unknown network communication status and computational *** limitation becomes notably significant in complex industrial networks of high-speed *** by these considerations,a data and model-driven task offloading problem is proposed in this paper.A redundant communication network is designed to adapt to anomalous channel states when tasks are offloaded to edge *** link switching mechanism is executed by the train according to the attributes of the completed *** task offloading optimization problem is formulated by introducing data-driven prediction of communication states into the traditional ***,the optimal strategy is achieved by employing the informer-based prediction algorithm and the quantum particle swarm optimization method,which effectively tackle real-time optimization problems due to their low time *** simulations illustrate that the data and model-driven task offloading strategy can predict the communication state in advance,thus reducing the cost of the system and improving its robustness.

关键词： Data driven model informer mobile edge computing quantum particle swarm optimization task offloading.

Investigation into microstructure of spray formed V4 cold working mould steel and its roiling and annealing

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Baosteel Technical Research 2008年第1期2卷 60-64页

作者： Shi Haisheng Yan Fei Fan Junfei le hairong fin Binzhong Peng Yong Advanced Technology Div. Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Key Laboratory for High Temperature Materials and Tests of Ministry of Education Shanghai Jiaotong University Shanghai 200030China

The material selected for this work was the spray formed Vanadis4 high alloy cold working mould steel （abbreviated to V4 steel）. Its microstructure, hot rolling process, and annealing treatment have been investigated. Observed from the optical and electron microscopes, the as-sprayed V4 steel had the finer microstructure of uniform and equiaxial grains ,while after hot rolling for densification and spheroidized annealing, the V4 steel obtained an excellent spheroidized structure that is favorable to subsequent quenching and tempering treatment. The spheroidized structure and level of annealed hardness of the V4 steel are almost the same as expensive imported powder metallurgy the V4 steel. It is difficult to produce V4 steel with the conventional ingot metallurgical technique, so the multi-step and high-cost powder metallurgy method is generally used at present. Compared to the powder metallurgy technique, using the spray forming technique to produce the V4 steel has obvious advantages and potential market competitiveness in reducing production costs, simplifying working process, and shortening the production cycle.

关键词： spray forming high alloy cold working mould steel rolling process and spheroidized annealing microstructure and micro-hardness

A study on mathematical simulation of spray forming process

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Baosteel Technical Research 2007年第1期1卷 37-41页

作者： Junfei Fan Yin Zhang Sanbing Ren hairong le Shunli Zhao Youduo He Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Institute of Metallurgical Engineering UIST Baotou Baotou 014010 China

An integrated approach for modeling the entire spray forming process is presented in this paper, and the program for the simulation is developed. The whole spray forming process can be divided into four calculation processes and the basis for the analysis is the classical k -ε turbulence model which was used to simulate the flow field of gas formed in the chamber. In the atomization model the flow field of gas is coupled with formation, velocity and location of droplet. By means of the above mathematical model, the process of spray forming was simulated.

关键词： spray forming droplets movement mathematical simulation

Novel self-assembled porous yolk-shell NiO nanospheres with excellent electrochromic performance for smart windows

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Particuology 2024年第1期84卷 72-80页

作者： Baoshun Wang Ya Huang Siming Zhao Run Li Di Gao hairong Jiang Rufan Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing100084China

With the rapid development of optoelectronics,electrochromic(EC)materials(ECMs)with the advan-tages of low power consumption,easy viewing,high contrast ratio,etc have attached more and more attention from the fields of smart windows,electronic billboards,emerging wearable and portable electronics,and other next-generation *** oxide(NiO)is a promising candidate for high-performance ECMs because of its neutral-colored states and low ***,NiO-based ECMs still face the problem of slow switching speed due to their low electrical conductivity and small lattice ***-organic frameworks(MOFs)are promising candidates to fabricate hollow and porous transition metal oxides(TMOs)with high ion transport efficiency,excellent specific capacitance,and electrochemical *** this work,porous yolk-shell NiO nanospheres(PYS-NiO NSs)were syn-thesized via a solvothermal and subsequent calcination process of Ni-MOF,which exhibited outstanding EC *** the large specific surface areas and hollow porous nanostructures were conducive to ionic transport,PYS-NiO NSs exhibited a fast coloring/bleaching speed(3.6/3.9 s per one coloring/bleaching cycle)and excellent cycling stability(82%of capacity retention after 3000 cycles).These superior EC properties indicated that the PYS-NiO NSs was a promising candidate for high-performance EC *** work provides a new and feasible strategy for the efficient preparation of TMOs ECMs with good EC performance,especially fast switching speed.

关键词： Electrochromic Nickel oxide Metal-organic frameworks Hollow structure Smart windows