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Numerical Study of Collision and Penetration Behavior Between Particles and Screen Plate

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Journal of China University of Mining and Technology 2006年第2期16卷 137-140,146页

作者： jiao Hong-guang ZHAO Yue-min WANG Quan-qiang School of Material Science and Engineering Henan Polytechnic University Jiaozuo Henan 454003 China School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

For a screening process, the collision and penetration phenomena between particles and screen plate is standard behavior and with collision the mechanical energy of the vibrating screen can be transmitted to the feed. In order to recognize further the collision process and the law of penetrating motion, with the spring-dashpot-slider contact model of the distinct element method （DEM）, a mathematical model which can describe the collision process has been established and a program for simulating the motion of a single particle on the screen plate developed by VC＋＋. NET. To evaluate the handling capacity of the screen that deals with difficult screening material, an instantaneous penetrating coefficient is defined. The moving period of the screen plate is divided into four stages. By analyzing the state of contact collision at each stage, it is pointed out that the collision ranging from 3π/2 to 2π period is the most favorable aperture for penetration of particles, while the collision ranging from π/2 to n period is the most unfavorable. The numerical simulation result further indicates that increasing the amplitude of the screen plate has a much greater effect on the augmentation of instantaneous penetration coefficient than increasing the vibration frequency.

关键词： screening numerical simulation particle motion collision

Using Leading Indicators to Improve Project Performance Measurement

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Journal of Systems Science and Systems Engineering 2019年第5期28卷 529-554页

作者： Li Zheng Claude Baron Philippe Esteban rui Xue qiang Zhang Shanlin Yang LAAS-CNRS Université de Toulouse Toulouse France School of Management Hefei University of Technology HefeiChina

Project performance measurement offers a wide range of methods to help project managers monitor ***,several critical issues remain in project performance measurement,such as an unbalanced use of indicators due to a lack of prediction-based (leading) indicators with regard to outcome-based (lagging) *** its part,systems engineering measurement,although a more recent discipline,offers a wide variety of indicators,including a set of leading *** our objective is to increase project performance and success rates,this involves improving project performance measurement on which project management decisions are *** purpose,the proposal put forward in this paper is to extend the number and type of indicators used in project performance measurement by adapting the leading indicators defined in systems engineering *** methodology involves first mapping the systems engineering indicators with the project management activities,resulting in identification of a set of potentially useful indicators for measuring the different activities,then tailoring a selection of these indicators with project-specific data to define a set of the most relevant indicators for a given *** methodology is illustrated by means of a case study in a manufacturing company.

关键词： Project performance measurement systems engineering measurement leading indicators lagging indicators

Recent advances in energy chemistry of precious-metal-free catalysts for oxygen electrocatalysis

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Chinese Chemical Letters 2018年第12期29卷 1757-1767页

作者： Bin Wang Xiaoyang Cui Jiaqi Huang rui Cao qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi'an 710119China CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

The oxygen evolution reaction(OER) and oxygen reduction reaction(ORR) are coupled with various sustainable energy systems and are significant for the future energy scenario. Both of them suffer from sluggish kinetics, which calls for cost-effective and high-performance electrocatalysts to promote. The oxygen electrolysis of OER and ORR is heterogeneous reaction, which involves reactant and electron transfer, and a serial of complicate surface reactions. Both intrinsic catalyst activity and extrinsic physicochemical characters play a vital role in overall electrocatalytic reactivity. Herein. recent advances in rational design and effective construction of precious-metal-free materials are reviewed for OER and ORR, respectively, in the respects of electronic structure regulation, nanostructure tailor, and freestanding electrode fabrication. The reaction mechanism of OER and ORR are also updated. This review provides emerging energy chemistry concepts and materials chemistry strategies of electrocatalysts for OER and ORR, which is also enlightening for other energy conversion devices with targeted optimization.

关键词： Oxygen electrocatalysis Oxygen reduction reaction Oxygen evolution reaction Metal-air batteries Nanostructured electrocatalysts

Doped low-density parity-check codes

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Digital Communications and Networks 2024年第1期10卷 217-226页

作者： Yong Li rui Liu Xianlong jiao Youqiang Hu Zhen Luo Francis C.M.Lau College of Computer Science Chongqing UniversityChongqing400044China School of Automation Chongqing UniversityChongqing400044China College of Electronic and Information Engineering Southwest UniversityChongqing400715China Future Wireless Networks and IoT Focusing Area Department of Electronic and Information EngineeringHong Kong Polytechnic UniversityHong KongChina

In this paper,we propose a doping approach to lower the error floor of Low-Density Parity-Check(LDPC)*** doping component is a short block code in which the information bits are selected from the coded bits of the dominant trapping sets of the LDPC ***,an algorithm for selecting the information bits of the short code is proposed,and a specific two-stage decoding algorithm is *** results demonstrate that the proposed doped LDPC code achieves up to 2.0 dB gain compared with the original LDPC code at a frame error rate of 10^(-6)Furthermore,the proposed design can lower the error floor of original LDPC Codes.

关键词： LDPC codes Doped LDPC codes Tanner graph Quadratic residue codes Trapping sets

General and Phosphine-Free Cobalt-Catalyzed Hydrogenation of Esters to Alcohols

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Chinese Journal of Chemistry 2019年第11期37卷 1125-1130页

作者： Zhihui Shao rui Zhong Raffaella Ferraccioli Yibiao Li qiang Liu Center of Basic Molecular Science(CBMS) Department of ChemistryTsinghua UniversityBeijing 100084China CNR Istituto di Scienze e Tecnologie Molecolari(ISTM)Via C.Golgi 1920133 MilanItaly School of Biotechnology and Health Sciences Wuyi UniversityJiang menGuangdong 529090China

Background and Originality Content Reduction of esters to alcohols is a fundamental transformation in organic chemistry,and is important for the production of a wide range of bulk and fine *** with traditional approaches using stoichiometric amounts of metal hydride reagents,catalytic hydrogenation represents an environmentally benign and atom economic alternative.

关键词： Hydrogenation hydrogenation alcohols

Change in Carbon Dioxide (CO_2) Emissions From Energy Use in China's Iron and Steel Industry

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Journal of Iron and Steel Research International 2011年第6期18卷 31-36页

作者： SUN Wen-qiang CAI Jiu-ju MAO Hu-jun GUAN Duo jiao State Environmental Protection Key Laboratory of Eco Industry Institute of Thermal and Environmental Engineering Northeastern University Shenyang 110819 Liaoning China Department of Energy and Power Engineering Shenyang Institute of Engineering Shenyang 110136 Liaoning China

As the largest energy consuming manufacturing sector and one of the most important sources of carhon dioxide （CO2） emissions, the China＇s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index （LMD1） technique is used to decompose total change in CO2 emissions into four factors： emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emis- sions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.

关键词： CO2 emissions energy use LMDI technique steel production energy consumption

Genetics and Molecular Mapping of Stripe Rust Resistance Gene YrShan515 in Chinese Wheat Cultivar Shan 515

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Agricultural Sciences in China 2011年第4期10卷 553-559页

作者： ZHANG Shu-ying XU Zhong-qing WANG rui LI qiang YAO qiang JING Jin-xue Shaanxi Key Laboratory of Molecular Biology for Agriculture~College of Plant Protection Northwest A＆F University Yangling 712100 P.R.China Qinghai Academy of Agriculture and Forestry Qinghai 810000 P.R. China

Stripe rust is one of the most important wheat diseases worldwide. To identify new resistance genes is significant in wheat breeding. In this study, stripe rust resistance of a Chinese cultivar Shan 515 was tested with Chinese predominant races of P. striiformis f. sp. tritici in the seedling stage, and genetic analysis and simple sequence repeats （SSR） technique were used to identify the inheritance model of seedling stripe rust resistance in cultivar Shan 515 and to mark the sites of resistance gene（s） on chromosome. The genetic analysis indicated that the resistance of Shan 515 against Su11-4 was conferred by a single dominant gene, which was temporarily designated as YrShan515. Using bulked segregant analysis （BSA） and SSR markers, 12 SSR markers （Xwmc335, Xwmc696, Xwmc476, Xbarc267, Xgwm333, Xwmc653, Xwmc396, Xgwm213, Xgwm112, Xgwm274, Xcfd22, Xgwm131, and Xwmc517） located on wheat chromosome 7BL were linked to YrShan515 with genetic distance ranging from 3 to 24 cM. Based on the previously published genetic map and Chinese Spring nulli-tetrasomic analysis, YrShan515 was located on wheat chromosome 7BL. Polymorphism of wheat cultivars collected from Huanghuai wheat grown regions were screened with two markers, Xwmc653 and Xbarc267, and all of these wheat cultivars tested did not present the polymorphic bands as Shan 515 did. Therefore, it suggested that YrShan515 might be a allele of the available yellow rust resistance gene. The mapping of the new resistance gene in Shan 515 is useful for wheat breeding and diversification of resistance genes against stripe rust in commercial wheat cultivars in China.

关键词： wheat cultivar Puccinia striiformis f. sp. Tritici resistance genes molecular mapping

Synthesis of Highly Branched Poly(ε-caprolactone) by Self-condensing Atom Transfer Radical Polymerization of Macroinimers

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Chinese Chemical Letters 2006年第3期17卷 373-376页

作者： rui Xue LIU Yan SHI Zhi Feng FU Shu Ke jiao Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing 100029

Branched poly（ε-capmlactone） was synthesized by self-condensing atom transfer radical polymerization of macroinimer, α-acryloyoxy-ω-2-bromopropionyloxy poly（ε-caprolactone）, which was prepared by enzyme-catalyzed ring-opening polymerization of ε-caprolactone with 2-hydroxylethyl acrylate as initiator and esterification of the ω-hydroxyl group of the obtained poly（ε-caprolactone） by 2-bromopropionyl bromide.

关键词： Self-condensing vinyl polymerization atom transfer radical polymerization branched polymers poly(ε-caprolactone).

Atom Probe Tomography Study of Fe Segregation at Phase Interface in Zr–2.5Nb Alloy

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Acta Metallurgica Sinica(English Letters) 2019年第10期32卷 1281-1286页

作者： Xue Liang qiang Li jiao Huang Mei-Yi Yao Hui Li Qing-Dong Liu Institute of Materials Shanghai University Shanghai 200072 China Laboratory for Microstructures Shanghai University Shanghai 200444 China School of Materials Science and Engineering Inner Mongolia University of Technology Hohhot 010051. China School of Nuclear Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

β-Nb is a typical second phase in Zr-Nb-based alloys used as fuel claddings in water-cooled nuclear reactors. The segregation of alloying element Fe may affect the corrosion resistance of Zr-Nb-based alloys. In this work, the Fe segregation at the interface between β-Nb phase and a-Zr matrix in Zr-2.5Nb alloy was studied using atom probe tomography and focused ion beam. The results suggested that the Fe concentration was much lower than Nb concentration in a-Zr matrix, while Fe selectively segregated at the β-Nb/a-Zr phase interface, leading to a Fe concentration peak at some interfaces. The peak Fe concentration varied from 0.4 to 1.2 at.% and appeared at the position where Zr concentration was approximately equal to Nb concentration. The selective segregation of Fe should be affected by the heat treatment and structure defects induced by cold rolling.

关键词： Zr-Nb alloy β-Nb phase Phase interface Segregation Atom probe tomography