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Journal of Iron and Steel Research International 2022年第1期29卷 124-131页

作者： dong-bin Jiang Li-feng Zhang Ya-dong Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Lab of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

The effect of mold electromagnetic stirring(M-EMS)on the solidification structure and solute segregation in the continuous casting bloom of U78CrV steel is *** solute distribution in the macroscale is analyzed using a carbon–sulfur analyzer and that in the microscale is measured with an electron probe *** Image-J software is applied to analyze the number density and area ratio of segregation *** results show that the segregation spots are mainly located in the columnar to equiaxed transition zone and the equiaxed zone,which are enriched with C,Cr,and Mn *** the M-EMS applied,the columnar grain inclines to the upstream *** the current intensity increases,the deflecting angle of columnar grain rises,especially with the current intensity larger than 300 ***,the center segregation shows a declining trend and the area fraction of the equiaxed zone rises ***,it is found that the area ratio and number density of segregation spots increase with the higher current intensity of M-EMS.

关键词： Solidification structure Macrosegregation Mesosegregation Segregation spot Mold electromagnetic stirring

pH Dependent plasmon-driven surface-catalysis reactions of p,p'-dimercaptoazobenzene produced from para-aminothiophenol and 4-nitrobenzenethiol

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Science China Chemistry 2012年第12期55卷 2567-2572页

作者： HUANG YingZhou dong bin Department of Applied Physics Chongqing UniversityChongqing400044China School of Physics and Materials Engineering Dalian Nationalities UniversityDalian116600China

In this paper,we studied the pH dependent plasmon-driven surface-catalysis(PDSC) reactions of p,p'-dimercaptoazobenzene(DMAB) produced from para-aminothiophenol(PATP) and 4-nitrobenzenethiol(4NBT) both theoretically and *** surface enhanced Raman spectrum(SERS) of DMAB produced from PATP and 4NBT on Ag films in solutions with various pH values has been *** simulation and experimental results indicated that the pH dependence of PATP appeared in acidic environment and came from the amino group ***,the ratio of intensity of Raman peak caused by PATP and DMAB indicated that this acidic sensor had higher pH sensitivity when it was excited by photons of higher energy.

关键词： plasmon-driven surface-catalysis pH senor SERS

Electrochemical disinfection using the gas diffusion electrode system

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Journal of Environmental Sciences 2010年第2期22卷 204-210页

作者： Wenying Xu Ping Li bin dong National Engineering Research Center for Urban Pollution Control Tongji University Shanghai 200092 China State Key Laboratory of PoUution Control and Resources Reuse Tongji University Shanghai 200092 China

A study on the electrochemical disinfection with H202 generated at the gas diffusion electrode （GDE） from active carbon/poly- tetrafluoroethylene was performed in a non-membrane cell. The effects of Pt load and the pore-forming agent content in GDE, and operating conditions were investigated. The experimental results showed that nearly all bacterial cultures inoculated in the secondary effluent from wastewater treatment plant could be inactivated within 30 min at a current density of 10 mA/cm^2. The disinfection improved with increasing Pt load. Addition of the pore-forming agent NH4HCO3 improved the disinfection, while a drop in the pH value resulted in a rapid rise of germicidal efficacy and the disinfection time was shortened with increasing oxygen flow rate. Adsorption was proved to be ineffective in destroying bacteria, while germicidal efficacy increased with current density. The acceleration rate was different, it initially increased with current density. Then decreased, and finally reached a maximum at a current density of 6.7 mA/cm^2. The disinfection also improved with decreasing total bacterial count. The germicidal efficacy in the cathode compartment was approximately the same as in the anode compartment, indicating that the contribution of direct oxidation and the indirect treatment of bacterial cultures by hydroxyl radical was similar to the oxidative indirect effect of the generated H2O2.

关键词： gas diffusion electrode cathode oxygen reduction electrochemical disinfection mechanism analysis

Aluminium nanohole arrays enhanced resonance Raman scattering spectra in the near ultraviolet region

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Science China(Physics,Mechanics & Astronomy) 2014年第12期57卷 2209-2213页

作者： WU YanQing dong bin School of Computer Science and Engineering Dalian Nationalities University School of Physics and Materials Engineering Dalian Nationalities University

Aluminium nanohole arrays with fixed diameter were fabricated by focused ion beam and the periodicities were *** nanohole arrays enhanced resonance Raman scattering spectra in the near ultraviolet region were studied ... 详细信息

关键词： aluminium nanohole arrays surface enhanced resonance Raman scattering

Effects of sludge age on anaerobic acidification of waste activated sludge: Volatile fatty acids production and phosphorus release

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Journal of Environmental Sciences 2021年第7期33卷 11-21页

作者： Sisi Chen Xiaohu Dai Dianhai Yang bin dong State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China

Effects of sludge age on volatile fatty acids (VFAs) production and Phosphorus (P) release during anaerobic acidification of waste activated sludge (WAS) were *** batch reactors (SBR) fed with simulating domestic sewage were applied to produce WAS of different sludge ages,and batch tests were used for anaerobic *** maximum dissolved total organic carbon,release of PO_(4)^(3+)-P,and accumulation of acetate (C2),propionate (C3),butyrate (C4),and valerate (C5) decreased by 56.2%,55.8%,52.6%,43.7%,82.4%and 84.8%,respectively,as the sludge age of WAS increased from 5 to 40 *** degradation of protein played a dominating role in decreasing DTOC and VFAs ***,the increase in molecular weight of organics and organic nitrogen content in the supernatant after acidification suggested that the refractory protein in WAS increased as sludge age *** the production of C2,C3,C4,and C5 from WAS decreased as the sludge age increased,the proportions of C2 and C3 in VFAs increased,which might be due to the declined production of C5 from protein and the faded genus *** sludge age of WAS at a relatively low level (<10 days) is more appropriate for anaerobic acidification of WAS as internal carbon sources and P resource.

关键词： Sludge age Waste activated sludge Acidification Volatile fatty acids Microbial community

Internal Polarization Field Induced Hydroxyl Spillover Effect for Industrial Water Splitting Electrolyzers

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Nano-Micro Letters 2024年第2期16卷 438-449页

作者： Jingyi Xie Fuli Wang Yanan Zhou Yiwen dong Yongming Chai bin dong State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580People’s Republic of China

The formation of multiple oxygen intermediates supporting efficient oxygen evolution reaction(OER)are affinitive with hydroxyl ***,ability of the catalyst to capture hydroxyl and maintain the continuous supply at active sits remains a tremendous ***,an affordable Ni2P/FeP2 heterostructure is presented to form the internal polarization field(IPF),arising hydroxyl spillover(HOSo)during *** by IPF,the oriented HOSo from FeP2 to Ni2P can activate the Ni site with a new hydroxyl transmission channel and build the optimized reaction path of oxygen intermediates for lower adsorption energy,boosting the OER activity(242 mV *** at 100 mA cm-2)for least 100 *** interestingly,for the anion exchange membrane water electrolyzer(AEMWE)with low concentration electrolyte,the advantage of HOSo effect is significantly amplified,delivering 1 A cm^(-2)at a low cell voltage of 1.88 V with excellent stability for over 50 h.

关键词： Hydroxyl spillover effect Internal polarization field Heterostructure Oxygen reduction reaction Anion exchange membrane water electrolysis

Learning Invariance Preserving Moment Closure Model for Boltzmann-BGK Equation

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Communications in Mathematics and Statistics 2023年第1期11卷 59-101页

作者： Zhengyi Li bin dong Yanli Wang School of Mathematical Sciences Peking UniversityBeijingPeople’s Republic of China Beijing International Center for Mathematical Research&Center for Machine Learning Research Peking UniversityBeijingPeople’s Republic of China Beijing Computational Science Research Center BeijingPeople’s Republic of China

As one of the main governing equations in kinetic theory,the Boltzmann equation is widely utilized in aerospace,microscopic flow,*** high-resolution simulation is crucial in these related ***,due to the high dimensionality of the Boltzmann equation,high-resolution simulations are often difficult to achieve *** moment method which was first proposed in Grad(Commun Pure Appl Math 2(4):331-407,1949)is among the popular numerical methods to achieve efficient high-resolution *** can derive the governing equations in the moment method by taking moments on both sides of the Boltzmann equation,which effectively reduces the dimensionality of the ***,one of themain challenges is that it leads to an unclosed moment system,and closure is needed to obtain a closedmoment *** is truly an art in designing closures for moment systems and has been a significant research field in kinetic *** than the traditional human designs of closures,the machine learning-based approach has attracted much attention lately in Han et al.(Proc Natl Acad Sci USA 116(44):21983-21991,2019)and Huang et al.(J Non-Equilib Thermodyn 46(4):355-370,2021).In this work,we propose a machine learning-based method to derive a moment closure model for the Boltzmann-BGK *** particular,the closure relation is approximated by a carefully designed deep neural network that possesses desirable physical invariances,i.e.,the Galilean invariance,reflecting invariance,and scaling invariance,inherited from the original Boltzmann-BGK equation and playing an important role in the correct simulation of the Boltzmann *** simulations on the 1D-1D examples including the smooth and discontinuous initial condition problems,Sod shock tube problem,the shock structure problems,and the 1D-3D examples including the smooth and discontinuous problems demonstrate satisfactory numerical performances of the proposed invariance preserving neural closure method

关键词： Boltzmann equation Moment closure Machine learning Neural networks Invariance preserving

Light-powered direction-controlled micropump

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Nano Research 2018年第4期11卷 1810-1821页

作者： Mingtong Li Yajun Su Hui Zhang bin dong Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University Suzhou 215123 China

A micropump induces the flow of its surrounding fluids and is extremely promising in a variety of applications such as chemical sensing or mass transportation. However, it is still challenging to manipulate its pumping direction. In this stud~ we examine a binary micropump based on perovskite and poly[（2-methoxy-5-ethylhexyloxy）-1,4-phenylenevinylene] （MEHPPV）. The micropump is operational under the influence of light. Light exhibits significant versatility in controlling the pumping phenomenon of the micropump. It governs the start and stop and also regulates the velocity and directions. The direction control signifies immense opportunities for the development of micropumps with unprecedented pumping behaviors and functions （such as heartbeat-like pumping, rectification, and amplification）. This makes them potentially useful in various fields. Hence, it is expected that the micropump reported in the current study could act as a key step towards the further development of more sophisticated micropumps for diverse applications.

关键词： micropump light powered density-driven thermal effect direction control

A new process to improve short-chain fatty acids and bio-methane generation from waste activated sludge

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Journal of Environmental Sciences 2016年第5期28卷 159-168页

作者： bin dong Peng Gao dong Zhang Yinguang Chen Lingling Dai Xiaohu Dai State Key Laboratory of Pollution Control and Resources Reuse School of Environmental Science and Engineering Tongji University

As an important intermediate product, short-chain fatty acids（SCFAs） can be generated after hydrolysis and acidification from waste activated sludge, and then can be transformed to methane during anaerobic digestion process. In order to obtain more SCFA and methane,most studies in literatures were centered on enhancing the hydrolysis of sludge anaerobic digestion which was proved as un-efficient. Though the alkaline pretreatment in our previous study increased both the hydrolysis and acidification processes, it had a vast chemical cost which was considered uneconomical. In this paper, a low energy consumption pretreatment method, i.e. enhanced the whole three stages of the anaerobic fermentation processes at the same time, was reported, by which hydrolysis and acidification were both enhanced, and the SCFA and methane generation can be significantly improved with a small quantity of chemical input. Firstly, the effect of different pretreated temperatures and pretreatment time on sludge hydrolyzation was compared. It was found that sludge pretreated at 100°C for 60 min can achieve the maximal hydrolyzation. Further, effects of different initial p Hs on acidification of the thermal pretreated sludge were investigated and the highest SCFA was observed at initial p H 9.0with fermentation time of 6 d, the production of which was 348.63 mg COD/g VSS（6.8 times higher than the blank test） and the acetic acid was dominant acid. Then, the mechanisms for this new pretreatment significantly improving SCFA production were discussed. Finally,the effect of this low energy consumption pretreatment on methane generation was investigated.

关键词： Low energy consumption process Short-chain fatty acids Waste activated sludge Methane generation

A Review on Deep Learning in Medical Image Reconstruction

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Journal of the Operations Research Society of China 2020年第2期8卷 311-340页

作者： Hai-Miao Zhang bin dong Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China

Medical imaging is crucial in modern clinics to provide guidance to the diagnosis and treatment of *** image reconstruction is one of the most fundamental and important components of medical imaging,whose major objective is to acquire high-quality medical images for clinical usage at the minimal cost and risk to the *** models in medical image reconstruction or,more generally,image restoration in computer vision have been playing a prominent *** mathematical models are mostly designed by human knowledge or hypothesis on the image to be reconstructed,and we shall call these models handcrafted ***,handcrafted plus data-driven modeling started to emerge which still mostly relies on human designs,while part of the model is learned from the observed *** recently,as more data and computation resources are made available,deep learning based models(or deep models)pushed the data-driven modeling to the extreme where the models are mostly based on learning with minimal human *** handcrafted and data-driven modeling have their own advantages and *** handcrafted models are well interpretable with solid theoretical supports on the robustness,recoverability,complexity,etc.,whereas they may not be flexible and sophisticated enough to fully leverage large data ***-driven models,especially deep models,on the other hand,are generally much more flexible and effective in extracting useful information from large data sets,while they are currently still in lack of theoretical ***,one of the major research trends in medical imaging is to combine handcrafted modeling with deep modeling so that we can enjoy benefits from both *** major part of this article is to provide a conceptual review of some recent works on deep modeling from the unrolling dynamics *** viewpoint stimulates new designs of neural network architectures with inspirations from optimization algorit

关键词： Medical imaging Deep learning Unrolling dynamics Handcrafted modeling Deep modeling Image reconstruction