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chinese Journal of Structural chemistry 2007年第2期26卷 143-148页

作者： TONG yi-Ping Department of chemistry Hanshan Normal University Chaozhou 521041 China

The title compound has been synthesized and characterized crystallographicaUy. It is a co-crystal consisting of two different neutral zinc（H） complexes with Hbpbm （Hbpbm = 4- bromo-2-（benzimidazol-2-yl）phenol） and Hnpbm （Hnpbm = 2-（1-butylbenzimidazol-2-yl）phenol）. One is a monomeric mixed-ligand complex of [Zn（bpbm）（npbm）] 1 and the other a dimer of [Zn2（npbm）4] 2 with their ratio of 2：1. Thus the overall formula for the title compound is 21.2. Adjacent 1 and 2 are connected to each other by intermolecular hydrogen bonding interactions in the lattice. The crystal data： monoclinic, space group P21/c, a = 15.0141（12）, b = 20.9941（17）, c = 18.4686（15） A, β = 97.445（2）°, V = 5772.4（8） A^3, Mr= 2429.68, Z = 2, Dc = 1.398 g/cm^3,μ = 1.579 -1 mm , F（000） = 2504, R = 0.0637 and wR = 0.1771 for 6464 observed reflections （I 〉 2σ（I））. The geometrical structure for 1 has also been theoretically optimized and compared with the experimental one.

关键词： zinc complex co-crystal structure 4-bromo-2-(1-butylbenzimidazol-2-yl)phenol 2-(1-butylbenzimidazol-2-yl)phenol

Friction and wear behavior and mechanism of low carbon microalloyed steel containing Nb

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china Foundry 2023年第3期20卷 263-270页

作者： Mei-yi Yuan Jia-cheng Zhang yi-tao Yang School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature,and the effect of Nb on the wear behavior of the steel,as welll as the mechanism was *** electron microscopy(SEM) and energy dispersive spectrometry(EDS) were employed to analyze the morphology and composition of the worn surface,and the structure evolution of the plastic deformation *** carbide content and type in the steel were analyzed by the electrolytic extraction device and X-ray diffraction(XRD).The experimental results demonstrate that the addition of 0.2% Nb can refine the grain and generate Nb c to improve the wear resistance of the *** enhancing the load and speed of wear experiment,the wear mechanism of the test steel with 0.2% Nb changes from slight oxidation wear to severe adhesion wear and oxidation *** with the load,the increase in the rotation speed exerts a greater influence on the wear of the test steel.

关键词： Nb content low carbon microalloyed steel friction and wear carbide

Effect of Temperature on the Release of Transparent Exopolymer Particles(TEP)and Aggregation by Marine Diatoms(Thalassiosira weissflogii and Skeletonema marinoi)

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Journal of Ocean University of china 2021年第1期20卷 56-66页

作者： cHEN Jie GUO Kangli Daniel cOThornton WU yi Fourth Institute of Oceanography Ministry of Natural ResourcesBeihai 536007China Department of Oceanography Texas A&M UniversityCollege StationTexas 77843USA

The presence of diatoms is accompanied by the production of a large amount of extracellular polymeric substances,which are mainly composed of *** exopolymer particles(TEP)are a large class of extracellular polymeric substances with high stickiness that promotes the formation of aggregates and marine snow,which affects marine bio-carbon pump *** purpose of this research was to determine how temperature increases affect the allocation of cellular carbohydrates and the formation and aggregation of *** results showed that the responses of two different diatom species(Thalassiosira weissflogii and Skeletonema marinoi)differed according to *** cell density and chlorophyll a concentration of the former were not significantly correlated with temperature,while those of the latter were significantly decreased with increasing *** indicates that the two species of diatom may have different heat tolerance ranges.A temperature increase will promote significant formation of TEP by both types of diatoms,including aggregation of *** as the temperature rises,meaning that the high temperature will produce an aggregate with a larger particle size and thus may increase the sedimentation rate of organic ***,the TEP aggregation of *** did not increase;therefore,its particle size was smaller,and so it may remain on the sea surface at high temperatures for longer *** influences have a profound impact on the biogeochemical cycling of carbon.

关键词： transparent exopolymer particles diatom Thalassiosira weissflogii Skeletonema marinoi aggregation

combinatorial auction algorithm for project portfolio selection and scheduling to maximize the net present value

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Journal of Zhejiang University-Science c(computers and Electronics) 2010年第7期11卷 562-574页

作者： Yong-yi SHOU yi-lun HUANG Department of Management Science & Engineering Zhejiang University Hangzhou 310058 China Department of Instrument Science & Engineering Zhejiang University Hangzhou 310027 China

Scheduling projects at the activity level increases the complexity of decision making of project portfolio selection but also expands the search space to include better project portfolios. An integer programming model is formulated for the project portfolio selection and scheduling problem. An iterative multi-unit combinatorial auction algorithm is proposed to select and schedule project portfolios through a distributed bidding mechanism. Two price update schemes are designed to adopt either a standard or an adaptive Walrasian tatonnement process. computational tests show that the proposed auction algorithm with the adaptive price update scheme selects and schedules project portfolios effectively and maximizes the total net present value. The price profile generated by the algorithm also provides managerial insights for project managers and helps to manage the scarce resources efficiently.

关键词： Project management Portfolio selection combinatorial auction Project scheduling

On Strong Metric Dimension of Graphs and Their complements

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Acta Mathematica Sinica,English Series 2013年第8期29卷 1479-1492页

作者： Eunjeong yi Texas A & M University at Galveston

A vertex x in a graph G strongly resolves a pair of vertices v, w if there exists a shortest x-w path containing v or a shortest x-v path containing w in G. A set of vertices SV（G） is a strong resolving set of G if every pair of distinct vertices of G is strongly resolved by some vertex in S. The strong metric dimension of G, denoted by sdim（G）, is the minimum cardinality over all strong resolving sets of G. For a connected graph G of order n≥2, we characterize G such that sdim（G） equals 1, n-1, or n-2, respectively. We give a Nordhaus–Gaddum-type result for the strong metric dimension of a graph and its complement： for a graph G and its complement G, each of order n≥4 and connected, we show that 2≤sdim（G）＋sdim（G）≤2（ n-2）. It is readily seen that sdim（G）＋sdim（G）=2 if and only if n=4; we show that, when G is a tree or a unicyclic graph, sdim（G）＋sdim（G）=2（n 2） if and only if n=5 and G ～=G ～=c5, the cycle on five vertices. For connected graphs G and G of order n≥5, we show that 3≤sdim（G）＋sdim（G）≤2（n-3） if G is a tree; we also show that 4≤sdim（G）＋sdim（G）≤2（n-3） if G is a unicyclic graph of order n≥6. Furthermore, we characterize graphs G satisfying sdim（G）＋sdim（G）=2（n-3） when G is a tree or a unicyclic graph.

关键词： Strong resolving set strong metric dimension Nordhaus–Gaddum-type tree unicyclic graph

Tumor growth and metastasis can be inhibited by maintaining genomic stability in cancer cells

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Frontiers of Medicine 2015年第1期9卷 57-62页

作者： yi Liang Sun Yat-sen University cancer center State Key Laboratory of Oncology in South china ' Collaborative Innovation Center for CancerMedicine Department of Experimental Research Department of Medical Oncology Sun Yat-sen University Cancer Center Guangzhou 510060 China Department of Hepatobiliary Oncology Affiliated Tumor Hospital Guangzhou Medical University Guangzhou 510095 China Peking Union Medical college Chinese Academy of Medical Sciences Beijing 100730 China

The existence of cancer stem cells, stem-like cancer cells （SLccs）, or tumor-initiating cells is considered as the cause of tumor formation and recurrence, indicating the importance of studying novel therapy that targets SLccs. The origin of SLccs is controversial because of two competing hypotheses： SLccs are either transformed from tissue adult stem cells or dedifferentiated from transformed progenitor cells. Our previous research demonstrates that SLccs are inducible by increasing genomic instability in cancer cells. In this study, to block the emergence of SLccs, aminoethyl isothiourea （AET）, a compound that clears free radicals and is used to protect patients from radioactive exposure, was used as an agent that maintains genomic stability in combination with mitomycin c （MMc）, a commonly used chemotherapeutic drug that damages DNA. Using a rabbit tumor model with VX2 hepatic carcinoma, we found that MMc alone increased lung metastases and disadvantaged survival outcome, but the combination of MMc and AET reversed this effect and even prolonged overall survival. Moreover, in a VX2 xenograft model by immunocompromised mice, MMc alone enriched tumor-initiating cells, but the administration of MMc in combination with AET eliminated tumor cells effectively. Furthermore, MMc alone enhanced genomic instability, but MMc combined with AET attenuated the extent of genomic instability in primary VX2 tumor tissue. Taken together, our data suggest that the genomic protector AET can inhibit the induction of SLccs, and this combination treatment by AET and cytotoxic agents should be considered as a promising strategy for future clinical evaluation.

关键词： rabbit VX2 liver tumor mitomycin c AET stem-like cancer cells genomic instability

Bainite isothermal transformation of Si–Mn–Mo alloy by phase structure factor calculation under different rare earth contents

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Rare Metals 2014年第4期33卷 427-432页

作者： Yan-Liang yi yi-Long Liang Qi-Bing Tan The Key Laboratory for Mechanical Behavior and Microstructure of Materials School of Materials and MetallurgyGuizhou University

The effect of rare earth （RE） on bainite trans- formation mechanism is not yet unified in the academia. Therefore, further studying the effect of RE on bainite transformation mechanism will have important guiding significance for the development of bainite steels. In this paper, using differential dilatometer （DIL805A/D）, heat treatment was performed and c-curve was drawn. The effect of phase structure factor on bainite transformation under two different fractions of RE in Si-Mn-Mo bainite steels was investigated by the empirical electron theory （EET） of solids, molecules, dilatometry, and metallogra- phy. Experimental results show that RE makes Fe-c- RE segregation structural unit of Si-Mn-Mo bainite steels increase, i.e., the values of phase structure factor （na, FDc） increase, and delay bainite transformation due to the drag effect resulting from the segregation of RE ferrite island interphase and the retardation of RE to carbon diffusion in Si-Mn-Mo bainite steels. Beside this, c-curve is shifted to right and down, and microstructures of bainite ferrite and substructures are finer.

关键词： Phase structure factor c-curve Substructure Rare earths

Activated carbon enhanced ozonation of oxalate attributed to HO·oxidation in bulk solution and surface oxidation: Effect of activated carbon dosage and pH

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Journal of Environmental Sciences 2014年第10期26卷 2095-2105页

作者： Linlin Xing Yongbing Xie Daisuke Minakata Hongbin cao Jiadong Xiao yi Zhang John c. crittenden National Engineering Laboratory for Hydrometallurgical cleaner Production Technology Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing Engineering Research center of Process Pollution control University of chinese Academy of Sciences Department of civil and Environmental Engineering Michigan Technological UniversityHoughton MI 49931 United States School of civil and Environmental Engineering Brook Byers Institute for Sustainable Systems Georgia Institute of TechnologyAtlantaGA 30332 United States

Ozonation of oxalate in aqueous phase was performed with a commercial activated carbon（Ac）in this work. The effect of Ac dosage and solution pH on the contribution of hydroxyl radicals（HOU） in bulk solution and oxidation on the Ac surface to the removal of oxalate was studied. We found that the removal of oxalate was reduced by tert-butyl alcohol（tBA） with low dosages of Ac,while it was hardly affected by tBA when the Ac dosage was greater than 0.3 g/L. tBA also inhibited ozone decomposition when the Ac dosage was no more than 0.05 g/L, but it did not work when the Ac dosage was no less than 0.1 g/L. These observations indicate that HOUin bulk solution and oxidation on the Ac surface both contribute to the removal of oxalate. HOU oxidation in bulk solution is significant when the dosage of Ac is low, whereas surface oxidation is dominant when the dosage of Ac is high. The oxalate removal decreased with increasing pH of the solution with an Ac dosage of 0.5 g/L. The degradation of oxalate occurs mainly through surface oxidation in acid and neutral solution, but through HOUoxidation in basic bulk solution. A mechanism involving both HOUoxidation in bulk solution and surface oxidation was proposed for Ac enhanced ozonation of oxalate.

关键词： Activated carbon Oxalate Ozonation Hydroxyl radicals Surface oxidation catalytic ozonation

Visible-light-mediated tungsten-catalyzed c-H amination of unactivated alkanes with nitroarenes

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Science china chemistry 2022年第4期65卷 678-685页

作者： Qing Wang Shengyang Ni Xiaochen Wang yi Wang yi Pan State Key Laboratory of coordination chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Alkylamines are important motifs in pharmaceutical and material *** existing reports of c-H amination are limited to ammonia,diazo and azide nitrogen *** work describes a rapid construction of c-N bonds from accessible nitroarene and alkane feedstock under decatungstate catalysis.A variety of c-H precursors including gaseous,linear,cyclic and benzylic hydrocarbons could adopt this protocol to afford the corresponding alkylamines in high efficiency.

关键词： amination photoredox light alkane nitrobenzene

Target tracking method of Siamese networks based on the broad learning system

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cAAI Transactions on Intelligence Technology 2023年第3期8卷 1043-1057页

作者： Dan Zhang c.L.Philip chen Tieshan Li yi Zuo Nguyen Quang Duy Navigation college Dalian Maritime UniversityDalianChina Innovation and Entrepreneurship Education college Dalian Minzu UniversityDalianChina computer Science and Engineering college South China University of TechnologyGuangzhouChina Department of computer and Information Science Faculty of Science and TechnologyUniversity of MacaoMacaoChina School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina Faculty of Navigation Vietnam Maritime UniversityHaiphongVietnam

Target tracking has a wide range of applications in intelligent transportation,real‐time monitoring,human‐computer interaction and other ***,in the tracking process,the target is prone to deformation,occlusion,loss,scale variation,background clutter,illumination variation,etc.,which bring great challenges to realize accurate and real‐time *** based on Siamese networks promotes the application of deep learning in the field of target tracking,ensuring both accuracy and real‐time ***,due to its offline training,it is difficult to deal with the fast motion,serious occlusion,loss and deformation of the target during ***,it is very helpful to improve the performance of the Siamese networks by learning new features of the target quickly and updating the target position in time *** broad learning system(BLS)has a simple network structure,high learning efficiency,and strong feature learning *** at the problems of Siamese networks and the characteristics of BLS,a target tracking method based on BLS is *** method combines offline training with fast online learning of new features,which not only adopts the powerful feature representation ability of deep learning,but also skillfully uses the BLS for re‐learning and re‐*** broad re‐learning information is used for re‐detection when the target tracking appears serious occlusion and so on,so as to change the selection of the Siamese networks search area,solve the problem that the search range cannot meet the fast motion of the target,and improve the *** results show that the proposed method achieves good results on three challenging datasets and improves the performance of the basic algorithm in difficult scenarios.

关键词： broad learning system siamese network target tracking