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New Matrix Loop Algebra and Its Application

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Communications in Theoretical Physics 2008年第8期50卷 321-325页

作者： DONG huan-He xu Yue-Cai College of Information Science and Engineering Shandong University of Science and Technology Qingdao 266510 China College of Continuing Education Shangdong University of Science and Technology Taian 271000 China

A new matrix Lie algebra and its corresponding Loop algebra are constructed firstly,as its application,the multi-component TC equation hierarchy is obtained,then by use of trace identity the Hamiltonian structure of the above system is ***,the integrable couplings of the obtained system is worked out by the expanding matrix Loop algebra.

关键词： matrix loop algebra Liouville integrable system Hamiltonian structure integrable couplings

Recent Advances of Single-atom Catalysts for Electro-catalysis

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Chemical Research in Chinese Universities 2022年第5期38卷 1146-1150页

作者： xu Guangyuan LIU Qin YAN huan Department of Chemical Physics University of Science and Technology of ChinaHefei 230026P.R.China

Single-atom catalysis is the“hot spot”in the field of catalysis due to the special geometries,electronic states,and their unique catalytic ***-atom catalysts(SACs),isolated metal atoms dispersed on the support,show the highest atom efficiency,cutting down the potential cost in the industrial ***,this“homo-hetero”catalyst could be a promising candidate for the next-generation *** applications for the SACs are widely reported,like gas-solid reactions,organic reactions,and *** this mini-review,we will focus on the recent work of SACs on electro-catalysis,including hydrogen evolution reaction(HER),oxygen reduction reaction(ORR),oxygen evolution reaction(OER),CO_(2) reduction reaction(CO_(2) RR),and nitrogen reduction reaction(NRR).

关键词： Sing-atom catalyst Hydrogen evolution reaction Oxygen reduction reaction Oxygen evolution reaction CO_(2)reduction reaction Nitrogen reduction reaction

Stereochemistry of Acetone Condensation on Solid Base Catalysts

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Chemical Research in Chinese Universities 1994年第1期10卷 25-30页

作者： Wang, Yu-huan Wang, guo-jia

ＳｔｅｒｅｏｃｈｅｍｉｓｔｒｙｏｆＡｃｅｔｏｎｅＣｏｎｄｅｎｓａｔｉｏｎｏｎＳｏｌｉｄＢａｓｅＣａｔａｌｙｓｔｓＷＡＮＧＹｕ－ｈｕａｎ；ａｎｄＷＡＮＧＧｕｏ－ｊｉａ（ＤｅｐａｒｌｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，Ｊｉｌ... 详细信息

ＳｔｅｒｅｏｃｈｅｍｉｓｔｒｙｏｆＡｃｅｔｏｎｅＣｏｎｄｅｎｓａｔｉｏｎｏｎＳｏｌｉｄＢａｓｅＣａｔａｌｙｓｔｓＷＡＮＧＹｕ－ｈｕａｎ；ａｎｄＷＡＮＧＧｕｏ－ｊｉａ（ＤｅｐａｒｌｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＪｉｌｉｎＵｎｉｖｅｒｓｉｔｙ．Ｃｈａｎ...

关键词： Isophorone Phorone Stereochemistry Condensation

Spanning tree-based algorithm for hydraulic simulation of large-scale water supply networks

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Water Science and Engineering 2010年第1期3卷 23-35页

作者： huan-feng DUAN guo-ping YU Department of Civil and Environmental Engineering Hong Kong University of Science and Technology Hong Kong P.. R. China College of Environmental Science and Engineering Tongji University Shanghai 200092 P. R. China

With the purpose of making calculation more efficient in practical hydraulic simulations, an improved algorithm was proposed and was applied in the practical water distribution field. This methodology was developed by expanding the traditional loop-equation theory through utilization of the advantages of the graph theory in efficiency. The utilization of the spanning tree technique from graph theory makes the proposed algorithm efficient in calculation and simple to use for computer coding. The algorithms for topological generation and practical implementations are presented in detail in this paper. Through the application to a practical urban system, the consumption of the CPU time and computation memory were decreased while the accuracy was greatly enhanced compared with the present existing methods.

关键词： large-scale networks, hydraulic simulation graph theory fundamental loop spanning tree efficiency

Experimental investigation on enhanced damage to fuel tanks by reactive projectiles impact

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Defence Technology（防务技术） 2021年第2期17卷 599-608页

作者： Hai-fu Wang Jian-wen Xie Chao Ge huan-guo guo Yuan-feng Zheng State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Enhanced damage to the full-filled fuel tank,impacted by the cold pressed and sintered PTFE/Al/W reactive material projectile(RMP)with a density of 7.8 g/cm3,is investigated experimentally and *** fuel tank is a rectangular structure,welded by six pieces of 2024 aluminum plate with a thickness of 6 mm,and filled with RP-3 aviation *** results show that the kerosene is ignited by the RMP impact at a velocity above 1062 m/s,and a novel interior ignition phenomenon which is closely related to the rupture effect of the fuel tank is ***,the traditional steel projectile with the same mass and dimension requires a velocity up to 1649 m/s to ignite the *** on the experimental results,the radial pressure field is considered to be the main reason for the shear failure of *** mechanism considerations,the chemical energy released by the RMP enhances the hydrodynamic ram(HRAM)effect and provides additional ignition sources inside the fuel tank,thereby enhancing both rupture and ignition ***,to further understand the enhanced ignition effect of RMP,the reactive debris temperature inside the kerosene is analyzed *** initiated reactive debris with high temperature provides effective interior ignition sources to ignite the kerosene,resulting in the enhanced ignition of the kerosene.

关键词： Reactive material projectile Fuel tank Enhanced damage effect Enhanced ignition mechanism Impact behavior

Learning from group supervision: the impact of supervision deficiency on multi-label learning

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Science China(Information Sciences) 2021年第3期64卷 5-17页

作者： Miao xu Lan-Zhe guo School of Information Technology and Electrical Engineering The University of Queensland RIKEN Center for Advanced Intelligence Project National Key Laboratory for Novel Software Technology Nanjing University

Multi-label learning studies the problem where one instance is associated with multiple *** supervised multi-label learning has attracted considerable research attention because of the annotation difficulty. Majority of the studies on weakly supervised multi-label learning assume that one group of weak annotations is available for each instance; however, none of these studies considers multiple groups of weak annotations that can be easily acquired through crowdsourcing. Recent studies on crowdsourced multilabel learning observed that the current query strategies do not agree well with human habits and that data cannot be collected as expected. Therefore, this study aims to design a new query strategy in accordance with human behavior patterns to obtain multiple groups of weak annotations. Further, a learning algorithm is proposed based on neural networks for such type of data. In addition, this study qualitatively and empirically analyzes factors in the proposed query strategy that may impact further learning and provides insights to obtain better query strategy with respect to future crowdsourcing in case of multi-label data.

关键词： multi-label learning weakly supervised leaning weakly supervised multi-label learning query strategy group supervision

UNIFIED WAY FOR DEALING WITH THREE-DIMENSIONAL PROBLEMS OF SOLID ELASTICITY

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Applied Mathematics and Mechanics(English Edition) 2001年第12期22卷 1357-1367页

作者： xu Qiang(许强) SUN huan-chun(孙焕纯) Department of Building Engineering Tongji University Shanghai 200092 P R China Department of Engineering Mechanics Dalian University of TechnologyDalian 116023 P R China

Unified way for dealing with the problems of three dimensional solid, each type of plates and shells etc. was presented with the virtual boundary element least, squares method(VBEM). It proceeded from the differential equations of three-dimensional theory of elasticity and employs the Kelvin solution and the least squares method, It is advantageous to the establishment of the models of a software for general application to calculate each type of three-dimensional problems of elasticity. Owing to directly employing the Kelvin solution and not citing any hypothesis, the numerical results of the method should be better than any others. The merits of the method are highlighted in comparison with the direct formulation of boundary element method (BEM). It is shown that coefficient matrix is symmetric and the treatment of singular integration is rendered unnecessary in the presented method. The examples prove the efficiency and calculating precision of the method.

关键词： virtual boundary element least squares method unified way of elasticity

Effect of Fluorination on the Photovoltaic Properties of Medium Bandgap Polymers for Polymer Solar Cells

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Chinese Journal of Chemistry 2018年第6期36卷 502-506页

作者： huan guo Wanbin Li Chunmei Chang Xia guo Maojie Zhang Laboratory of Advanced Optoelectronic Materials College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou Jiangsu 215123 China

Fluorination of conjugated polymers is one of the effective strategies to tune the molecular energy levels and morphology for high efficient polymer solar cells （PSCs）. Herein, two novel donor-acceptor conjugated polymers, PffBT and PBT, based on bis（3,5-bis（hexyloxy）phenyl）benzo[1,2- b：4,5-b＇]dithiophene and benzo[c][1,2,5]thiadiazole （BT） with or without fluorination, respectively, were synthesized, and their photovoltaic properties were compared. The polymer PffBT based on fluorinated BT showed lower frontier energy levels, improved polymer ordering, and a well-developed fibril structure in the blend with PC71BM. As a result, the PSCs based on PffBT/PC71BM exhibit a superior power conversion efficiency （PCE） of 8.6% versus 4.4% for PBT-based devices, due to a high space charge limit current （SCLC） hole mobility, mixed orientation of polymer crystals in the active layer, and low bimolecular recombination.

关键词： benzo[c][1 2 5]thiadiazole conjugated polymers fluorination polymer solar cells power conversion efficiency

Power-Law Behavior in Signal Scattering Process in Vertical Granular Chain with Light Impurities

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Communications in Theoretical Physics 2001年第12期36卷 699-704页

作者： xu Ai-guo Department of Physics and Center for Strongly Correlated Materials Research Seoul National University Seoul 151-742.Korea

We investigate the scattering process of impulse in vertical granular chain with light impurities. When the perturbation is weak, the quantities describing the reflection rate exhibit power-law behavior with the impurity depth. The exponent is nearly independent of vi. When the perturbation is very strong, the vertical chain shows similar behavior to that of the horizontal chain, so the exponent is nearly zero. Our numerical investigation begins from the weak perturbation region and extends to the nonlinear region and found a peak of the exponent. The difficulty in extending the numerical investigation to a stronger perturbation region is *** numbers: 45.70.-n, 43.25.+y, 46.40.

关键词： granular chain, scattering process, power-law behavior, reflection rate