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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 360-364页

作者： Yan-ping Zeng Hong-mei Fan Xi-shan Xie School of Materials Science and Engineering University of Science and Technology Beijing

The fatigue cracking behavior of ultra-high strength steels containing rectangular inclusions of small sizes were investigated based on in situ observations by scanning electron microscopy （SEM）. The size and shape of rectangular inclusions affect markedly the initiation site and propagation path of a fatigue crack. Especially, the initiation site of a fatigue crack depends strongly on the angle between the long-axis of a rectangle inclusion and the loading direction, and the length/width ratio of this rectangle inclusion because the residual stress distribution fields vary with these conditions. The results coincide very well with those of finite element analysis.

关键词： high strength steel inclusions fatigue of materials crack initiation crack propagation

Involvements of chloride ion in decolorization of Acid Orange 7 by activated peroxydisulfate or peroxymonosulfate oxidation

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Journal of Environmental Sciences 2011年第11期23卷 1799-1807页

作者： ping Wang Shiying Yang Liang shan Rui Niu Xueting Shao Key Laboratory of Marine Environment and Ecology Ministry of EducationQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

The effects of chloride anion （Cl-）（up to 1.0 mol/L） on the decolorization of a model compound,azo dye Acid Orange 7 （AO7）,by sulfate radical （SO4-） based-peroxydisulfate （PS） or peroxymonosulfate （PMS） oxidation under various activated conditions （UV 254 nm /PS,Thermal （70°C/PS,UV 254 nm /PMS,Co 2＋ /PMS） were *** and NH4 ＋ were used as quenching reagents to determine the contributions of active chlorine species （dichloride radical （Cl2-.） and hypochlorous acid （HClO））.The results indicated that the effects of Cl- on the reaction mechanism were different under various activated *** UV/PS and Thermal/PS,the inhibition tendency became more clear as the Cl- concentration increased,probably due to the reaction between Cl- and SO4-.and the generation of Cl2-.or *** UV/PMS,Cl- did not exhibit inhibition when the concentration was below 0.1 mol/*** Cl- concentration reached to 1.0 mol/L,the decolorization rate of AO7 was,however,accelerated,possibly because PMS directly reacts with Cl- to form *** Co2＋ /PMS,Cl- exhibited a significant inhibiting effect even at low concentration （ 0.01 mol/L）.When Cl- concentration exceeded 0.1 mol/L,the activation of PMS by Co 2＋ was almost completely *** this condition,HClO maybe played a major role in decolorization of *** results implicated that chloride ion is an important factor in SO4-.-based degradation of organic contamination in chloride-containing water.

关键词： chloride anion activated peroxydisulfate oxidation activated peroxymonosulfate oxidation radicals decolorization

Cooperative effect between copper species and oxygen vacancy in Ce_(0.7−x)Zr_(x)Cu_(0.3)O_(2) catalysts for carbon monoxide oxidation

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1524-1536页

作者： shan Wang Xuelian Xu ping Xiao Junjiang Zhu Xinying Liu Institute for the Development of Energy for African Sustainability College of ScienceEngineering and TechnologyUniversity of South AfricaJohannesburg1710South Africa Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan430200China

The effects of Zr doping on the existence of Cu and the catalytic performance of Ce_(0.7−x)Zr_(x)Cu_(0.3)O_(2)for CO oxidation were *** characterization results showed that all samples have a cubic structure,and a small amount of Zr doping facilitates Cu^(2+) ions entering the CeO2 lattice,but excessive Zr doping leads to the formation of surface CuO crystals ***,the number of oxygen vacancies caused by the Cu^(2+) entering the lattice(e.g.,Cu^(2+)-□-Ce^(4+);□:oxygen vacancy),and the amount of reducible copper species caused by CuO crystals,varies with the Zr *** CO oxidation tests indicated that the oxygen vacancy and the reducible copper species were the adsorption and activation sites of O_(2)and CO,respectively,and the cooperative effects between them accounted for the high CO oxidation ***,the samples x=0.1 and 0.3,which possessed the most oxygen vacancy or reducible copper species,showed the best activity for CO oxidation,with full CO conversion obtained at 110℃.The catalyst is also stable and has good resistance to water during the reaction.

关键词： Ce-Zr-Cu-O CO oxidation reducible copper species oxygen vacancy cooperative effect

A junction-by-junction feedback-based strategy with convergence analysis for dynamic traffic assignment

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Science China(Information Sciences) 2016年第1期59卷 30-46页

作者： Tengfei LIU Xuesong lu Zhong-ping JIANG State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Department of Electrical and Computer Engineering University of Connecticut Department of Electrical and Computer Engineering Polytechnic School of Engineering New York University

By considering the traffic assignment problem as a control problem, this paper develops a new realtime route guidance strategy for accurate convergence of the traffic flows to user equilibrium(UE) or system optimum(SO), in the presence of drivers’ response uncertainties. With the new guidance strategy, the drivers make routing decisions based on the route guidance information from junction to junction. Specifically, instead of total travel cost of every route from origin to destination, the travel cost of every alternative link plus the average cost to destination from the next junction corresponding to the alternative link is sent to the drivers at each specific junction. The drivers’ response to the route guidance information is directly modeled by the splitting rates at the junctions, which are simply negatively correlated with the comparison of related cost information and are able to take into account the drivers’ response uncertainties. With the proposed route guidance strategy, in the case of fixed travel demands, the accurate convergence of the traffic flows to a UE is guaranteed in the presence of drivers’ response uncertainties by using La Salle’s invariance principle. When marginal travel cost information, instead of travel cost information, is sent to the drivers, a system optimum can be achieved under a mild condition on the marginal cost function.

关键词： dynamic traffic assignment user equilibrium(UE) system optimum(SO) convergence La Salle’s invariance principle

Hierarchical topic modeling with nested hierarchical Dirichlet process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 858-867页

作者： Yi-qun DING shan-ping LI Zhen ZHANG Bin SHEN School of Computer Science and Technology Zhejiang University Hangzhou 310027 China State Street Hangzhou Hangzhou 310000 China

This paper deals with the statistical modeling of latent topic hierarchies in text corpora. The height of the topic tree is assumed as fixed, while the number of topics on each level as unknown a priori and to be inferred from data. Taking a nonpara-metric Bayesian approach to this problem, we propose a new probabilistic generative model based on the nested hierarchical Dirichlet process (nHDP) and present a Markov chain Monte Carlo sampling algorithm for the inference of the topic tree structure as well as the word distribution of each topic and topic distribution of each document. Our theoretical analysis and experiment results show that this model can produce a more compact hierarchical topic structure and captures more fine-grained topic rela-tionships compared to the hierarchical latent Dirichlet allocation model.

关键词： Topic modeling Natural language processing Chinese restaurant process Hierarchical Dirichlet process Markovchain Monte Carlo Nonparametric Bayesian statistics

DETECTION METHOD OF SPOT WELDING BASED ON MULTI-INFORMATION FUSION AND FRACTAL

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 76-81页

作者： LIU Pengfei shan ping luO Zhen SHEN Junqi QIN Hede luoyang Ship Material Research Institute Luoyang 471039 China School of Material Science and Engineering Tianjin University Tianjin 300072 China School of Xinxiang Etectromechanical Engineering Xinxiang 453000 China

A novel detection method of support vector machine （SVM） based on fractal dimension of signals is presented. And models of SVM are made based on nugget size defects of spot welding. Classification using these trained SVM models is done to signals of spot welding. It is shown from effect of different SVM models that these models with different inputs. In detection of defects, these models with inputs including sound signal have a high percentage of accuracy, the detection accuracy of these models with inputs including voltage signal will reduce. So the SVM models based on fractal dimensions of sound are some optimal nondestructive detection ones. At last a comparison between SVM detection model and ANNS detection model is researched which indicates that SVM is a more effective measure than Artificial neural networks in detection of nugget size defects during spot welding.

关键词： Multi-information fusion Support vector machine Box counting dimension Detection Spot welding

Construction of Orthogonal Arrays without Interaction Columns

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 159-168页

作者： shan-qi PANG Ya-ping WANG Ming-yao AI School of Mathematics and Information Science Henan Engineering Laboratory for Big Data Statistical Analysis and Optimal ControlHenan Normal UniversityXinxiang 453007China KLATASDS-MOE School of StatisticsEast China Normal UniversityShanghai 200062China LMAM School of Mathematical Sciences and Center for Statistical SciencePeking UniversityBeijing 100871China

In this paper a new class of orthogonal arrays(OAs),i.e.,OAs without interaction columns,are proposed which are applicable in factor screening,interaction detection and other *** the tools of difference matrices,we present some general recursive methods for constructing OAs of such *** families of OAs with high percent saturation are *** particular,for any integerλ≥3,such a two-level OA of run 4λcan always be obtained if the corresponding Hadamard matrix exists.

关键词： complex aliasing difference matrix Hadamard matrix Kronecker sum symmetric array

Mechanisms of phosphate removal from aqueous solution by blast furnace slag and steel furnace slag

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 125-132页

作者： Sheng-gao lu Shi-qiang BAI Hong-dan shan College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.

关键词： Phosphate removal Blast furnace slag (BFS) Steel furnace slag (SFS) Adsorption Precipitation

Plantation transformation alternatives determine carbon sequestration capacity – a case study with Pinus massoniana in southern China

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Journal of Mountain Science 2020年第4期17卷 919-930页

作者： RUAN lu-ping lu Yuan-chang MENG Jing-hui Research Center of Forest Management Engineering of National Forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China Institute of Forest Resource and Information Techniques Chinese Academy of ForestryBeijing 100091China

It is widely accepted that global warming, which results from the increase of carbon dioxide(CO2) in the atmosphere, has a negative impact on human beings. Forests are the largest terrestrial ecosystem and play an important role in carbon sequestration. Many studies have documented that a mixed-species forest can sequester more carbon than single species forests, depending on the site conditions. Therefore, uneven-aged mixed-species forest management has been receiving more and more attention. In 2008, an experiment with five silvicultural models for Pinus massoniana(Chinese red pine) plantation, i.e., four transformation treatments(A1-A4) and one control treatment(A5) was conducted in the Experimental Center of Tropical Forestry of Chinese Academy of Forestry in pingxiang City, in southwestern Guangxi Zhuang Autonomous Region, southern China. The four transformation treatments(A1-A4) enriched Castanopsis hystrix, Manglietia glance, Erythrophleum fordii and Quercus griffithii with differed richness and composition after thinning(removed 70% of trees), while no silvicultural treatment was used in the control treatment A5. In this study, we compared the carbon sequestration capacity of these five silvicultural models based on periodic annual increment and growth rate. Our results indicated that all the transformation treatments performed significantly better in carbon sequestration than the control treatment. A significant difference was also observed amongst the transformation treatments. Moreover, the transformation treatment A1 with enrichment species Castanopsis hystrix(350 trees·ha^-1) and Manglietia glance(350 trees·ha^-1) was determined to be the optimal model for maximum carbon sequestration because of its high tree-level growth rate and high economic value of enriched plantings, which could be popularized in other places. Our results further confirmed that management using mixed-species forests is a better approach to combat climate change than using monocult

关键词： Global warming Carbon sequestration Mixed-species forest Silvicultural model Singlespecies(monoculture)forest

Copolymerization of Ethylene with 10-Undecen-1-ol Using Highly Active Vanadium(Ⅲ) Precatalysts Bearing Bis(imino)pyrrolyl Ligands

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Chinese Journal of Polymer Science 2014年第5期32卷 603-608页

作者： Ling-pan lu Jing-shan Mu 李悦生 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences University of the Chinese Academy of Sciences Changchun Branch The school of Materials Science and Chemical Engineering Ningbo University

The copolymerizations of ethylene with 10-undecen-1-ol have been investigated using vanadium precatalysts, bis（imino）pyrrolyl vanadium（Ⅲ） complexes 1-3, 2,5-C4H2N（CH=NR）2VCl2（THF）2 [R = C6H5 （1）, 2,6-iPr2C6H3 （2）, C6F5 （3）], and the iminopyrrolyl and b-diketiminate ones for comparison. The polar monomer was pretreated by diethylaluminium chloride （present also as the cocatalyst） before the copolymerization. The monomer reactivity ratios were evaluated using the Fineman-Ross method. The ligand structure considerably influenced the catalytic activity and tolerance towards the polar monomer, the polar monomer incorporation and the molecular weights of the resultant copolymers. The bis（imino）pyrrolyl vanadium complexes exhibited promising catalytic performance for the copolymerization, and a high catalytic activity up to 3.84 kg/mmolv·h with a high comonomer incorporation of 14.0 mol% was achieved by complex 3 under mild conditions.

关键词： Ziegler-Natta polymerization Copolymerization Functional polyolefin.