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Capped carbon nanotube-based molecular switch

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science Bulletin 2010年第13期55卷 1227-1230页

作者： zhao peng1, WANG PeiJi1, ZHANG Zhong1 & liu desheng2 1 school of science, university of jinan, jinan 250022, china 2 school of Physics, State Key Laboratory of Crystal Materials, Shandong university, jinan 250100, china school of science University of Jinan Jinan China school of Physics State Key Laboratory of Crystal Materials Shandong University Jinan China

Using the Landauer formalism that combines both the non-equilibrium Green's function (NEGF) and first-principles density functional theory (DFT), the electron transport characteristics of one-dimensional molecular switching device based on the capped carbon nanotubes have been investigated. The results show that the transmission can be efficiently tuned within two orders of magnitude just by changing 0.2 nm of the tube-tube separation. Moreover, the electron transport is insensitive to the topology of the facing conformations which can improve the practical stability of the chosen system as a molecular switch.

关键词： carbon nanotube molecular switch non-equilibrium Green function density functional theory

Repetitious-Hot-Pressing Technique in Hot-Pressing Process

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Journal of Materials science & Technology 2003年第5期19卷 486-488页

作者： Shixue SONG, Xing AI, Wei GAO and Jun zhao1)school of Mechanical Engineering, Shandong university, jinan 250061, china2)school of science, jinan university, jinan 250022, china school of Mechanical Engineering Shandong University Jinan 250061 China school of science Jinan University Jinan 250022 China

A new pressing method was proposed for hot-pressing process. Experimental results indicated that the porosity in Al2O3/TiC/ Ni/Mo (hereafter called AI2O3/TiC composite) composite compacts decreases by 6% after adopting this new technique, compared to traditional hot-pressing technique under the same sintering temperature. The flexural strength and Vicker hardness increase from 883 MPa to 980 MPa and from 16 GPa to 21.1 GPa, respectively. A theoretical model was given to analyze the densification mechanism of the composite in the process of repetitious-hot-pressing.

关键词： Hot-pressing sintering Repetitious-hot-pressing sintering Composite

Novel stacking models based on SMOTE for the prediction of rockburst grades at four deep gold mines

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Underground Space 2024年第6期19卷 169-188页

作者： peng Xiao Zida liu Guoyan zhao pengzhi Pan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China school of Resources and Safety Engineering Central South UniversityChangsha 410083China

Rockburst is a frequently encountered hazard during the production of deep gold *** prediction of rockburst is an important measure to prevent rockburst in gold *** study considers seven indicators to evaluate rockburst at four deep gold *** research and rock tests were performed at two gold mines in china to collect these seven indicators and rockburst *** collected database was oversampled by the synthetic minority oversampling technique(SMOTE)to balance the categories of rockburst *** models combining tree-based models and logistic regression(LR)were established by the balanced *** datasets from another two deep gold mines were implemented to verify the applicability of the predictive *** stacking model combining extremely randomized trees and LR based on SMOTE(SMOTE-ERT-LR)was the best model,and it obtained a training accuracy of 100%and an evaluation accuracy of 100%.Moreover,model evaluation suggested that SMOTE can enhance the prediction performance for weak rockburst,thereby improving the overall ***,sensitivity analysis was performed for *** results indicated that the SMOTE-ERT-LR model can achieve satisfactory performance when only depth,maximum tangential stress index,and linear elastic energy index were available.

关键词： Rockburst prediction Gold mine Stacking model SMOTE

Reverse extraction of early-age hydration kinetic equation from observed data of Portland cement

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science china(Technological sciences) 2010年第6期53卷 1540-1553页

作者： WANG Lin1,YANG Bo2,zhao XiuYang1,2,CHEN YueHui2 & CHANG Jun3 1 school of Computer science and Technology,Shandong university,jinan 250101,china 2 Provincial Key Laboratory for Network-based Intelligent Computing,university of jinan,jinan 250022,china 3 school of Material science and Engineering,university of jinan,jinan 250022,china school of Computer science and Technology Shandong University Jinan China Provincial Key Laboratory for Network-based Intelligent Computing University of Jinan Jinan China school of Material science and Engineering University of Jinan Jinan China

The early-age hydration of Portland cement paste has an important impact on the formation of microstructure and development of ***,manual derivation of hydration kinetic equation is very difficult because there are multi-phased,multi-sized and interrelated complex chemical and physical reactions during cement *** this paper,early-age hydration kinetic equation is reversely extracted automatically from the observed time series of hydration degree of Portland cement using evolutionary computation method that combines gene expression programming and particle swarm optimization *** order to reduce the computing time,GPUs are used for acceleration in *** have shown that according to the extracted kinetic equation,simulation curve of early-age hydration is in good accordance with the observed experimental ***,this equation still has a good generalization ability even changing chemical composition,particle size and curing conditions.

关键词： Portland cement hydration kinetic equation reverse extraction gene expression programming particle swarm optimization

Local saliency consistency-based label inference for weakly supervised salient object detection using scribble annotations

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 239-249页

作者： Shuo zhao peng Cui Jing Shen Haibo liu school of Computer science and Technology Harbin University of Science and TechnologyHarbinChina school of Computer science and Technology Harbin Engineering UniversityHarbinChina

Recently,weak supervision has received growing attention in the field of salient object detection due to the convenience of ***,there is a large performance gap between weakly supervised and fully supervised salient object detectors because the scribble annotation can only provide very limited foreground/background ***,an intuitive idea is to infer annotations that cover more complete object and background regions for *** this end,a label inference strategy is proposed based on the assumption that pixels with similar colours and close positions should have consistent ***,k-means clustering algorithm was first performed on both colours and coordinates of original annotations,and then assigned the same labels to points having similar colours with colour cluster centres and near coordinate cluster ***,the same annotations for pixels with similar colours within each kernel neighbourhood was set *** experiments on six benchmarks demonstrate that our method can significantly improve the performance and achieve the state-of-the-art results.

关键词： label inference salient object detection weak supervision

Negative differential resistance in molecular devices: the role of molecule-electrode coupling

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science china(Physics,Mechanics & Astronomy) 2011年第8期Mechanics & Astronomy) .卷 1455-1460页

作者： ZHAI YaXin1, JI GuoMin1, FANG ChangFeng1, CUI Bin1, zhao peng2 & liu desheng1,3, 1 school of Physics, State Key Laboratory of Crystal Materials, Shandong university, jinan 250100, china 2 school of science, university of jinan, jinan 250022, china 3 Department of Physics and Information Engineering, Jining university, Qufu 273100, china school of Physics State Key Laboratory of Crystal Materials Shandong University Jinan China school of science University of Jinan Jinan China Department of Physics and Information Engineering Jining University Qufu China

By applying nonequilibrium Green's function formalism combined with the first-principles density functional theory, we investigate the electronic transport in two molecular junctions constituted by a substituted oligo (phenylene ehtynylene) sand-wiched between two Au electrodes. Our calculations show that the weak molecule-electrode coupling is responsible for the observation of the negative differential resistance (NDR) effect in experiments. When the coupling is weak, the projected density of states (PDOS) of the molecule and the electrodes undergoes a mismatch-match-mismatch procedure, which increases and then decreases the transmission peak intensities, leading to a NDR effect. We also find that the localization/delocalization of the molecular orbitals and the change of charge state of the molecule have no direct relation with the NDR effect, because they change little as the voltage increases.

关键词： negative differential resistance substituted oligo (phenylene ehtynylene) molecular junction density functional theory nonequilibrium Green’s function formalism

Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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Chinese Journal of Polymer science 2024年第7期42卷 984-991,I0009页

作者： Xu-Fei liu Chong-Rui Zhang Hua-Wen peng Qiang zhao Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion ***,the design of adhesives for natural seawater represents challenges less ***,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural *** combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in *** instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural *** design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.

关键词： Coacervate Underwater adhesives Seawater Cation-dipole interaction

Tuning interface mechanism of FeCo alloy embedded N,S-codoped carbon substrate for rechargeable Zn-air battery

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Journal of Energy Chemistry 2024年第6期93卷 400-410,I0010页

作者： Hui Chang Lulu zhao Shan zhao Zong-Lin liu peng-Fei Wang Ying Xie Ting-Feng Yi school of Materials science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004HebeiChina

The interface mechanism between catalyst and carbon substrate has been the focus of *** this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis *** experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon *** FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for *** addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle *** results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.

关键词： FeCo alloy N S co-doped carbon DFT calculation Zn-air batteries Interfacial interaction

Towards Effective Author Name Disambiguation by Hybrid Attention

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Journal of Computer science & Technology 2024年第4期39卷 929-950页

作者： Qian Zhou Wei Chen peng-peng zhao An liu Jia-Jie Xu Jian-Feng Qu Lei zhao school of Computer science and Technology Soochow UniversitySuzhou 215006China

Author name disambiguation(AND)is a central task in academic search,which has received more attention recently accompanied by the increase of authors and academic *** tackle the AND problem,existing studies have proposed various approaches based on different types of information,such as raw document features(e.g.,co-authors,titles,and keywords),the fusion feature(e.g.,a hybrid publication embedding based on multiple raw document features),the local structural information(e.g.,a publication's neighborhood information on a graph),and the global structural information(e.g.,interactive information between a node and others on a graph).However,there has been no work taking all the above-mentioned information into account and taking full advantage of the contributions of each raw document feature for the AND problem so *** fill the gap,we propose a novel framework named EAND(Towards Effective Author Name Disambiguation by Hybrid Attention).Specifically,we design a novel feature extraction model,which consists of three hybrid attention mechanism layers,to extract key information from the global structural information and the local structural information that are generated from six similarity graphs constructed based on different similarity coefficients,raw document features,and the fusion *** hybrid attention mechanism layer contains three key modules:a local structural perception,a global structural perception,and a feature ***,the mean absolute error function in the joint loss function is used to introduce the structural information loss of the vector *** results on two real-world datasets demonstrate that EAND achieves superior performance,outperforming state-of-the-art methods by at least+2.74%in terms of the micro-F1 score and+3.31%in terms of the macro-F1 score.

关键词： author name disambiguation multiple-feature information hybrid attention pruning strategy structural information loss of vector space