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Oral health in China-trends and challenges

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International Journal of Oral Science 2011年第1期3卷 7-12页

作者： De-yu Hu xiao Hong xue Li State Key Laboratory of Oral Diseases Sichuan University Chengdu 610041 China

For a long time, oral disease is one of the major problems of the public health for its high prevalence and incidence throughout the world, which is especially true for low-income populations. Since China＇s economic reform in 1978, great changes have taken place in China. These changes have significant impact on and have been reflected in oral disease trends in China. This paper provides an overview and assessment of the oral health status in China. It focuses on changes in the nation＇s demographic profile, in the marketplace, the oral disease status and trends. The paper also suggests some possible measures and strategies for bettering oral health in future China.

关键词： national epidemiology survey oral health public health oral health system

A high-efficiency separation process of Fe and Zn from zinc-bearing dust by direct reduction

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Journal of Iron and Steel Research International 2022年第10期29卷 1559-1572页

作者： Ding-zheng Wang De-qing Zhu Jian Pan Zheng-qi Guo Hong-yu Tian yu-xiao xue School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina

It is urgent to dispose of zinc-bearing dust from steel plants,and direct reduction process is an effective method to remove hazardous metals and recycle iron from the *** reduction behavior of carbon-containing pellets which were made from three kinds of zinc-bearing dust was *** the pellets were reduced at 1200℃ for 50 min,the reduced pellets with cold compressive strength of 1164 N pellet−1 and Zn content<0.1 wt.%could be directly used as burden for improving the blast furnace operation without further *** results of isothermal kinetic study showed that the iron oxide reduction rate was controlled by the chemical *** strengthening mechanism of reduced pellets and iron oxide reduction mechanism was investigated by thermodynamic calculation besides X-ray diffraction,scanning electron microscopy combined with energy dispersive spectrometry,and optical microscopy *** was found that higher temperatures are required for the reduction of spinel phase(zinc ferrite)and olivine phase(hedenbergite).The generation and growth of metallic iron bridges could significantly increase the compressive strength of reduced *** iron oxide reduction in the carbon-containing pellets followed the uniform internal reduction model and possessed a high apparent reaction rate,which can improve energy utilization rate and production efficiency.

关键词： Zinc-bearing dust Reduction mechanism Kinetics High efficiency Direct reduction

Significant influence of self-possessed moisture of limonitic nickel laterite on sintering performance and its action mechanism

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Journal of Iron and Steel Research International 2022年第9期29卷 1368-1380页

作者： yu-xiao xue De-qing Zhu Jian Pan Zheng-qi Guo Hong-yu Tian Gen Li Qing-zhou Huang Liao-ting Pan xue-zhong Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Guangxi Beibu Gulf New Material Co. Ltd.Beihai 536000GuangxiChina

In consideration of the abundant moisture of limonitic nickel laterite mined,it is essential to determine whether the selfpossessed moisture of limonitic nickel laterite after pre-dried is appropriate for ***,based on the characterization of limonitic nickel laterite,the influence of its self-possessed moisture on sintering performance was expounded by sinter pot tests and the relevant mechanism was revealed by the systematical analyses of the granulation properties of sinter mixture,thermodynamic conditions during sintering and mineralogy of product *** results indicate that the selfpossessed moisture of limonitic nickel laterite indeed has significant infuence on its sintering *** the optimum self-possessed moisture of 21 mass%,sinter indices are relatively better with tumble index,productivity and solid fuel rate of 48.87%,1.04 t m^(-2) h^(-1)and 136.52 kg t^(-1),respectively,due to the superior granulation properties of sinter mixture and thermodynamic conditions during sintering,relatively large amount of silico-ferrite of calcium and alumina and tighter sinter ***,sintering performance of limonitic nickel laterite is still much poorer than that of ordinary iron *** is feasible to strengthen limonitic nickel laterite sintering by inhibiting the over-fast sintering speed and improving the thermodynamic conditions during sintering.

关键词： Limonitic nickel laterite Self-possessed moisture Sintering performance Action mechanism:Stainless steel

Difference of sintering performance of different types of limonitic nickel laterite

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Journal of Iron and Steel Research International 2023年第1期30卷 21-30页

作者： yu-xiao xue Jian Pan De-qing Zhu Xin Wang Bo-hua Li Wei Liu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

To achieve the more extensive utilization of limonitic nickel laterite,the difference of sintering performance of different types of limonitic nickel laterite including high-gangue and low-gangue nickel ores was investigated by sinter pot tests and relevant mechanism analyses such as thermodynamic analysis and the chemistry and mineralogy of product *** the type of limonitic nickel laterite transformed from high-gangue to low-gangue nickel ore,tumble index and productivity are improved from 45.87%and 0.97 t m^(-2) h^(-1) to 50.16%and 1.05 t m^(-2) h^(-1),respectively,and solid fuel rate is reduced from 140.52 to 131.13 kg/t,indicating that the low-gangue nickel ore possesses relatively better sintering *** is mainly due to the fact that the much lower contents of MgO and Al2O3 improve the formation ability and fluidity of liquid phase,which eventually contributes to the formation of relatively tighter sinter microstructure with the lower sinter porosity,more silico-ferrite of calcium and alumina amount and better bonding of hercynite by liquid *** addition,the metallurgical performance and nickel content of product sinter would not be reduced as different types of limonitic nickel laterite are blended for *** this basis,it is entirely feasible to more widely utilize limonitic nickel laterite and simultaneously obtain much better-quality Ni-containing product sinter via effective sintering strengthening technologies.

关键词： Limonitic nickel laterite Sintering Stainless steel High-melting component Extensive utilization

Achieving efficient utilization of limonitic nickel laterite and CO_(2) emission reduction through multi-force field sintering process

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Journal of Iron and Steel Research International 2022年第11期29卷 1734-1747页

作者： yu-xiao xue De-qing Zhu Zheng-qi Guo Jian Pan Yi-ge Wang Qing-zhou Huang Liao-ting Pan xue-zhong Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Guangxi Beibu Gulf New Materials Co. Ltd.Beihai 536000GuangxiChina

Strengthening limonitic nickel laterite sintering and reducing CO_(2) emission were performed by the application of multiforce fields including external thermodynamic and pressure *** pot tests of limonitic nickel laterite were carried out,and the relevant industrial production was *** chemistry and mineralogy of product sinter and the thermodynamic and kinetic conditions during sintering were analyzed to reveal the relevant *** results indicate that sintering performance of limonitic nickel laterite in the new sintering process with multi-force fields is significantly improved with tumble index and productivity increased by 24.11%and 18.56%,respectively,and solid fuel rate reduced by 23.21%,compared with those in traditional sintering *** this case,greenhouse and pollutant gas emissions are greatly reduced,and metallurgical performances of product sinter are *** industrial production has been successfully conducted,indicating a bright application *** analysis shows that the great improvement of thermodynamic and kinetic conditions during sintering and the densification of loose sinter can be achieved via the application of multi-force *** microstructure is transformed from large thin-wall pores to small thin-wall pores or medium thick-wall pores with the dramatic reduction of sinter porosity and more formation of silico-ferrite of calcium and alumina(SFCA).Meanwhile,the homogenization of mineral compositions is achieved,and much denser interlocking texture between hercynite and SFCA is *** application of multi-force fields contributes to the substantial improvement of sintering performance of limonitic nickel laterite and CO_(2) emission reduction.

关键词： Limonitic nickel laterite Multi-force field Sintering performance CO_(2)emission reduction Efficient utilization

Computational Experiments for Complex Social Systems:Integrated Design of Experiment System

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1175-1189页

作者： xiao xue Xiangning yu Deyu Zhou xiao Wang Chongke Bi Shufang Wang Fei-yue Wang College of Intelligence and Computing Tianjin UniversityTianjin 300350China School of Software Shandong UniversityJinan 250101China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China Institute of Automation Chinese Academy of Sciences Beijing 100190China

Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social *** mechanical analysis and social simulations alone are powerless for analyzing complex social *** this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain ***,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and *** a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key *** paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment ***,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework.

关键词： artificial system operations

Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick

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Journal of Iron and Steel Research International 2024年第6期31卷 1344-1354页

作者： Peng-bo Liu Shu-sen Cheng yu-qing xue xiao-man Cheng Zhao Liu University of Science and Technology Beijing Beijing 100083China Ministry of Ironmaking Shangdong Taishan Steel Group Co.Ltd.Taian 271000ShandongChina

The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the *** brick and ramming material in the hearth of a 1780 m3 blast furnace after shutdown were sampled and *** was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn_(2)SiO_(4),whereas the substances in the cracks of the carbon brick below the taphole were *** reaction of Zn with CO,SiO_(2),and Fes generates ZnO,Zn_(2)SiO_(4),and ZnS,resulting in volume expansion,which is an important reason for the cracking of carbon ***,several obvious Zn vapor flow channels were found in the ramming material,through which Zn vapor could enter the carbon brick,causing damage to the carbon *** the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material,reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.

关键词： Zn Blast furnace Carbon brick Ramming material Crack

Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1022-1038页

作者： xiao xue Deyu Zhou Xiangning yu Gang Wang Juanjuan Li Xia Xie Lizhen Cui Fei-yue Wang the School of Computer Software College of Intelligence and ComputingTianjin UniversityTianjin 300350China the School of Software and the Joint SDUNTU Centre for Artificial Intelligence Research(C-FAIR) Shandong UniversityJinan 250101China the Information School Xi’an University of Financial and EconomicsXi’an 710100China the State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Hainan University Haikou 570228China the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 1001901China

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system *** address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating ***,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

关键词： Agent-based modeling computational experiments cyber-physical-social systems(CPSS) generative deduction generative experiments meta model

p-d Orbital Hybridization Engineered Single-Atom Catalyst for Electrocatalytic Ammonia Synthesis

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Energy & Environmental Materials 2024年第2期7卷 119-125页

作者： Jingkun yu xue Yong Siyu Lu Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China Department of Chemistry University of SheffieldSheffieldS37HFUK

The rational design of metal single-atom catalysts(SACs)for electrochemical nitrogen reduction reaction(NRR)is ***-dimensional metal-organic frameworks(2DMOFs)is a unique class of promising *** to now,the roles of individual metals,coordination atoms,and their synergy effect on the electroanalytic performance remain ***,in this work,a series of 2DMOFs with different metals and coordinating atoms are systematically investigated as electrocatalysts for ammonia synthesis using density functional theory *** a specific metal,a proper metal-intermediate atoms p-d orbital hybridization interaction strength is found to be a key indicator for their NRR catalytic *** hybridization interaction strength can be quantitatively described with the p-/d-band center energy difference(Δd-p),which is found to be a sufficient descriptor for both the p-d hybridization strength and the NRR *** maximum free energy change(ΔG_(max))andΔd-p have a volcanic relationship with OsC_(4)(Se)_(4)located at the apex of the volcanic curve,showing the best NRR *** asymmetrical coordination environment could regulate the band structure subtly in terms of band overlap and *** work may shed new light on the application of orbital engineering in electrocatalytic NRR activity and especially promotes the rational design for SACs.

关键词： first-principle calculations Nitrogen reduction p-d orbital hybridization single-atom catalysts