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Nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun Chen Jian gang wang Hui Zhao Guoliang Zhang Zengxi Li Chunshan Li State Key Laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of Ni single-atom coordinated with N and S(Ni-NSC)through the pyrolysis of organic Ni-based precursors at600℃.The existence and fine structure of Ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared Ni-NSC catalyst exhibited higher activity and stability than theNi/NSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of Ni single-atom and weak adsorption energy of intermediates on these Ni sites.

关键词： methyl acrylate mild hydrogenation Ni single-atom coordination environment adsorption energy

一种ICEEMDAN-CNN-SVR滑坡位移组合预测模型

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三峡大学学报（自然科学版） 2025年第1期47卷 37-43页

作者：石化波王刚曾怀恩中煤湖北地质勘察基础工程有限公司武汉430070 中铁建城建交通发展有限公司江苏苏州215000 湖北长江三峡滑坡国家野外科学观测研究站湖北宜昌443002 三峡大学土木与建筑学院湖北宜昌443002

滑坡位移预测是滑坡早期预警系统的重要组成部分,针对位移分解程度与特征选取深入程度不够导致滑坡位移预测精度不高的问题,提出一种ICEEMDAN-CNN-SVR滑坡位移组合预测模型:为了解决位移分解程度不够的问题,该模型首先运用ICEEMDAN分解... 详细信息

滑坡位移预测是滑坡早期预警系统的重要组成部分,针对位移分解程度与特征选取深入程度不够导致滑坡位移预测精度不高的问题,提出一种ICEEMDAN-CNN-SVR滑坡位移组合预测模型:为了解决位移分解程度不够的问题,该模型首先运用ICEEMDAN分解模型对滑坡位移曲线进行分解,将平滑性较好且具有递增趋势的IMF曲线作为趋势项位移,将其他具有波动趋势的IMF曲线总和重构为周期项位移;为了解决特征选取深入程度不够的问题,针对不同位移特性进行了特征变量选取,通过二维平铺与CNN特征提取得到特征变量更深层次的信息,将提取到的特征信息输入SVR预测模型中实现对趋势项位移与周期项位移的精准预测.以典型堆积层滑坡———八字门滑坡为例,选取ZG110与ZG111监测点2007年1月—2012年9月典型变形阶段水平位移数据进行研究,结果表明:ZG110与ZG111监测点预测评价指标R2,ERMSE,EMAE分别为0.9951、0.9989、5.7489、2.7532,4.5091、1.8529,预测效果良好;将模型预测结果与EEMDCNN-SVR预测模型及CNN-SVR预测模型结果作对比,相较其他预测模型,新模型的预测精度有所提升.

关键词：八字门滑坡 ICEEMDAN分解特征提取 CNN-SVR模型对比分析

SYMMETRIC VORTICAL STRUCTURE AND ITS TOPOLOGICAL STABILITY

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Journal of Hydrodynamics 2005年第5期17卷 552-557页

作者： wang gang LIANG Xin-gang gang Ming-li Department of Engineering Mechanics Tsinghua University Beijing 100084 China Exploration and Development Research Institute PetroChina Daqing Oilfield Company Ltd. Daqing 163712 China

Using time dependent compressible laminar Navier-Stokes equations with a finite volume method incorporating a third-order-accurate discretization scheme, the flow structures around a slender at certain incidences are numerical simulated and typical crossflow patterns are presented. At incidence 10°, these vortical configurations are different at dissimilar axial locations though they are symmetric. At 35°, the symmetric vortical structures still maintain over the slender, yet their interaction at afterbody is intense than that at the forehody since the two vortices have fully developed downstream. The unstable topological structure of trajectory of saddle-to-saddle points and multiple limit cycle are further discussed in topological stability theory. These structures easily produce bifurcation with perturbation. The results support the view of hydrodynamic instability of vortices flow field.

关键词： symmetric vortices slender body flow pattern topological stability flow mechanism

Analysis of the tetraquark and hexaquark molecular states with the QCD sum rules

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Communications in Theoretical Physics 2021年第6期73卷 80-93页

作者： Zhi-gang wang Department of Physics North China Electric Power UniversityBaoding 071003China

In this article,we construct the color-singlet-color-singlet type currents and the color-singlet-colorsinglet-color-singlet type currents to study the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*,D*D*D*hexaquark molecular states with the QCD sum rules in *** calculations,we choose the pertinent energy scales of the QCD spectral densities with the energy scale formula■for the tetraquark and hexaquark molecular states respectively in a consistent *** obtain stable QCD sum rules for the scalar D*■*,D*D*tetraquark molecular states and the vector D*D*■*hexaquark molecular state,but cannot obtain stable QCD sum rules for the vector D*D*D*hexaquark molecular *** connected(nonfactorizable)Feynman diagrams at the tree level(or the lowest order)and their induced diagrams via substituting the quark lines make positive contributions for the scalar D*D*tetraquark molecular state,but make negative or destructive contributions for the vector D*D*D*hexaquark molecular *** is of no use or meaningless to distinguish the factorizable and nonfactorizable properties of the Feynman diagrams in the color space in the operator product expansion so as to interpret them in terms of the hadronic observables,we can only obtain information about the short-distance and long-distance contributions.

关键词： tetraquark molecular states hexaquark molecular states QCD sum rules

Synthesis of amphiphilic fluorinated Janus particles with applications in stabilizing surfactant-free foams

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Particuology 2018年第6期16卷 112-117页

作者： gang wang Keliang wang Ying wang Ministry of Education Key Laboratory of Enhanced Oil Recovery Technology Northeast Petroleum UniversityDaqing 163318China State Key Laboratory oflnorganic Synthesis &Preparative Chemistry Jilin UniversityChangchun 130012China

We report the preparation of amphiphilic Janus particles covered with fluorinated chains as well as the self-assembly and foam stabilization property of these particles over a limited range of *** structure and properties of these particles were characterized using scanning electron microscopy,Fourier transform infrared spectroscopy,fluorescence microscopy,pendant drop tensiometer,and *** a particle concentration of 0.6wt%,the adsorption of the Janus particles at the interface was saturated and an equilibrium surface tension of approximately 35mN/m was obtained. No further decreases in surface tension were observed with additional increases in the particle *** a concentration of 0.4wt%,the Gibbs stability criterion was achieved and the foam volume was almost constant throughout the observation ***,the liquid fraction of the foam exhibited a static equilibrium at each concentration assessed,demonstrating that drainage was arrested *** results confirm that the use of amphiphilic Janus particles is an efficient approach to stabilizing foams.

关键词： Janus particle Fluorinated grafting agent Amphiphilic particle Self-assembly Dynamic surface tension Foam stability

Index Geographic Gossip Algorithm for Information Dissemination over Regular Graphs

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Chinese Journal of Electronics 2019年第2期28卷 386-391页

作者： wang gang LIN Zun wang Fuxiang School of Electrical and Information Engineering Beihang University China Mobile Communications Group Co.Ltd

An Index geographic gossip(IGG)algorithm is proposed. Relay nodes participate in information exchange and updating. The cumulative number of times these nodes participate is characterized by an index number, which can be used to accelerate information updating. The convergence property of the IGG algorithm is theoretically analyzed in ring and grid network topologies. The IGG algorithm improves the standard gossip algorithm by a gain of O(n) in both convergence time and communication cost. Compared to the geographic gossip algorithm, the IGG algorithm has a gain on the order of O(n) and O(n1/2) in the average hop count for information exchange and communication cost, respectively. Finally, the proposed IGG algorithm is compared with various baselines through simulations,and it is shown that significant performance gain can be achieved.

关键词： Information dissemination Gossip algorithm Node mobility Geography

Exergy Analysis of Photo-Thermal Interaction Process between Solar Radiation Energy and Solar Receiver

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Journal of Thermal Science 2021年第5期30卷 1541-1547页

作者： wang gang wang Cheng CHEN Zeshao School of Energy and Power Engineering Northeast Electric Power UniversityJilin132012China School of Engineering Science University of Science and Technology of ChinaHefei230027China

A unified theory of non-equilibrium radiation thermodynamics is always in search as it is meaningful for solar energy *** exergy analysis of photo-thermal interaction process between the solar radiation energy and solar receiver is conducted in this *** non-equilibrium radiation thermodynamic system is *** thermodynamic process of photo-thermal interaction between the solar radiation and solar receiver is ***,exergy and entropy equations for the photo-thermal process are *** for calculating the optimum receiving temperatures of the solar receiver under both non-concentration and solar concentration conditions are presented.A simple solar receiver is chosen as the calculation example to launch the exergy analysis under non-concentration ***,the effect analysis of solar concentration on the thermodynamic performance of the solar receiver for solar thermal utilization is carried *** analysis results demonstrate that both the output exergy flux and efficiency of the solar receiver can be improved by increasing the solar concentration ratio during the solar thermal utilization *** formulas and results provided in this paper may be used as a theoretical reference for the further studies of non-equilibrium radiation thermodynamic theory and solar thermal utilization.

关键词： non-equilibrium radiation thermodynamics solar energy exergy analysis optimum receiving temperature solar thermal utilization

Exploring electronic-level principles how size reduction enhances nanomaterial surface reactivity through experimental probing and mathematical modeling

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Nano Research 2022年第4期15卷 3812-3817页

作者： Guolei Xiang Yang-gang wang State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Department of Chemistry Southern University of Science and TechnologyShenzhen 518000China

Size reduction can generally enhance the surface reactivity of inorganic *** origin of this nano-effect has been ascribed to ultrasmall size,large specific surface area,or abundant defects,but the most intrinsic electronic-level principles are still not fully understood *** combining experimental explorations and mathematical modeling,herein we propose an electronic-level model to reveal the physicochemical nature of size-dependent nanomaterial surface ***,we reveal that competitive redistribution of surface atomic orbitals from extended energy band states into localized surface chemical bonds is the critical electronic process of surface chemical interactions,using H_(2)O_(2)-TiO_(2)chemisorption as a model ***,we define a concept,orbital potential(G),to describe the electronic feature determining the tendency of orbital redistribution,and deduce a mathematical model to reveal how size modulates surface *** expose the dual roles of size reduction in enhancing nanomaterial surface reactivity-inversely correlating to orbital potential and amplifying the effects of other structural factors on surface reactivity.

关键词： surface reactivity size effect electronic mechanism chemisorption strength surface coordination bond

Enterprise resource planning implementation decision & optimization models

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Journal of Systems Engineering and Electronics 2008年第3期19卷 513-521页

作者： wang Shaojun wang gang Lü Min Gao Guoan Advanced Manufacturing Technology Center Harbin Inst. of Technology Harbin 150001 P. R. China

To study the uncertain optimization problems on implementation schedule, time-cost trade-off and quality in enterprise resource planning （ERP） implementation, combined with program evaluation and review technique （PERT）, some optimization models are proposed, which include the implementation schedule model, the timecost trade-off model, the quality model, and the implementation time-cost-quality synthetic optimization model. A PERT-embedded genetic algorithm （GA） based on stochastic simulation technique is introduced to the optimization models solution. Finally, an example is presented to show that the models and algorithm are reasonable and effective, which can offer a reliable quantitative decision method for ERP implementation.

关键词： optimization model ERP chance-constrained programming PERT genetic algorithm time cost,quality.

Particle contact angle at the oil-water interface: Effect of surface silanization

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Particuology 2019年第3期17卷 218-224页

作者： Keliang wang gang wang Chunjing Lu Key Laboratory of Enhanced Oil Recovery of Ministry Education Northeast Petroleum University Daqing 163000 China

A novel and efficient method was developed to vary the particle contact angle (θ) at the wax-water interface by tailoring the degree of Υ-aminopropyltriethoxysilane (APTES) grafting onto silica *** three-phase θ determines the degree of particle penetration into the respective *** the APTES grafting density of the silica particles resulted in a three-phase θ increase from 22° to 70°.Furthermore,increasing APTES grafting density results in silica particles packing more closely and orderly on the surface of the wax colloidosomes.A series of fluorinated Janus particles were prepared by the subsequent surface chemical modification of the modified silica particles adsorbed on the wax *** particles with tailored APTES grafting densities can be utilized to tune the Janus balance during the synthesis of Janus particles based on Pickering emulsion methods.

关键词： Janus particles Surface modification Aminopropyltriethoxysilane Pickering emulsions Contact angle