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Weak Graph Map Homotopy and Its Applications

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Chinese Annals of Mathematics,Series b 2024年第2期45卷 235-252页

作者： Conglei zhang Yanying WANG zhiguo zhang Yan zHAO School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China Department of basic Science Shanxi Agricultural UniversityJinzhang 030801ShanxiChina Center for Topology and Geometry based Technology School of Mathematical SciencesHebei Normal UniversityShijiazhuang 050024China School of Mathematical Sciences Hebei Normal UniversityTaiyuan 030031China School of Mathematics and Computer Science Shanxi Normal UniversityShijiazhuang 050024China School of Mathematics and Science Hebei GEO UniversityShijiazhuang 050031China

The authors introduce a notion of a weak graph map homotopy(they call it M-homotopy),discuss its properties and *** prove that the weak graph map homotopy equivalence between graphs coincides with the graph homotopy equivalence defined by Yau et al in *** difference between them is that the weak graph map homotopy transformation is defined in terms of maps,while the graph homotopy transformation is defined by means of combinatorial *** discuss its advantages over the graph homotopy *** its applications,they investigate the mapping class group of a graph and the 1-order M P-homotopy group of a pointed simple ***,they show that the 1-order M P-homotopy group of a pointed simple graph is invariant up to the weak graph map homotopy equivalence.

关键词： Weak graph map homotopy Trivial vertex Strong deformation retract Mapping class group MP-Homotopy group

Mo_(2)b_(2)O_(2)Mbene for Efficient Electrochemical CO Reduction to C_(2)Chemicals:Computational Exploration

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Energy & Environmental Materials 2024年第6期7卷 342-350页

作者： bikun zhang Jianwen Jiang Department of Chemical and biomolecular Engineering National University of SingaporeSingapore 117576Singapore

Emerging as a new class of two-dimensional materials with atomically thin layers,Mbenes have great potential for many important applications such as energy storage and *** mitigating carbon footprint,there has been increasing interest in CO_(2)/CO conversion on Mbenes,but mostly focused on C_(1)products.C^(2+)chemicals generally possess higher energy densities and wider applications than C_(1)***,C–C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this ***,we explore electrochemical CO reduction reaction to C_(2)chemicals on Mo_(2)b_(2)O_(2)Mbene via density-functional theory ***,the most favorable CO–COH coupling is revealed to be a spontaneous and barrierless process,making Mo_(2)b_(2)O_(2)an efficient catalyst for C–C *** C_(1)and C_(2)chemicals,ethanol is predicted to be the primary ***,by charge and bond analysis,it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate*COH than other C_(1)intermediates,which is responsible for the facile C–C *** an atomic scale,this work provides microscopic insight into C–C coupling process and suggests Mo_(2)b_(2)O_(2)a promising catalyst for electrochemical CO reduction to C_(2)chemicals.

关键词： C_(2)chemicals C-C coupling density-functional theory Mbene Mo2b2O2

Hybrid Dynamic Variables-Dependent Event-Triggered Fuzzy Model Predictive Control

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 723-733页

作者： Xiongbo Wan Chaoling zhang Fan Wei Chuan-Ke zhang Min Wu IEEE the School of Automation China University of Geosciencesthe Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systemsand the Engineering Research Center of Intelligent Technology for Geo-ExplorationMinistry of EducationWuhan 430074China

This article focuses on dynamic event-triggered mechanism(DETM)-based model predictive control(MPC) for T-S fuzzy systems.A hybrid dynamic variables-dependent DETM is carefully devised,which includes a multiplicative dynamic variable and an additive dynamic *** addressed DETM-based fuzzy MPC issue is described as a “min-max” optimization problem(OP).To facilitate the co-design of the MPC controller and the weighting matrix of the DETM,an auxiliary OP is proposed based on a new Lyapunov function and a new robust positive invariant(RPI) set that contain the membership functions and the hybrid dynamic variables.A dynamic event-triggered fuzzy MPC algorithm is developed accordingly,whose recursive feasibility is analysed by employing the RPI *** the designed controller,the involved fuzzy system is ensured to be asymptotically *** examples show that the new DETM and DETM-based MPC algorithm have the advantages of reducing resource consumption while yielding the anticipated performance.

关键词： Dynamic event-triggered mechanism(DETM) hybrid dynamic variables model predictive control(MPC) robust positive invariant(RPI)set T-S fuzzy systems

Encoding and display technologies for combinatorial libraries in drug discovery:The coming of age from biology to therapy

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Acta Pharmaceutica Sinica b 2024年第8期14卷 3362-3384页

作者： Yu Fan Ruibing Feng Xinya zhang zhen-Liang Wang Feng Xiong Shuihua zhang zhang-Feng zhong Hua Yu Qing-Wen zhang zhang zhang Yitao Wang Guodong Li Macao Centre for Research and Development in Chinese Medicine State Key Laboratory of Quality Research in Chinese MedicineInstitute of Chinese Medical SciencesUniversity of MacaoMacao SAR 999078China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao SAR 999078China International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development Ministry of Education(MoE)of People’s Republic of ChinaCollege of PharmacyJinan UniversityGuangzhou 510632China zhuhai UM Science and Technology Research Institute Zhuhai 519031China Department of Pharmacy Guangzhou Red Cross HospitalFaculty of Medical ScienceJinan UniversityGuangzhou 510632China Geriatric Medicine First People’s Hospital of XinXiang and the Fifth Affiliated Hospital of Xinxiang Medical CollegeXinxiang 453100China Shenzhen Innovation Center for Small Molecule Drug Discovery Co. Ltd.Shenzhen 518000China

Drug discovery is a sophisticated process that incorporates scientific innovations and cuttingedge *** to traditional bioactivity-based screening methods,encoding and display technologies for combinatorial libraries have recently advanced from proof-of-principle experiments to promising tools for pharmaceutical hit discovery due to their high screening efficiency,throughput,and resource *** review systematically summarizes the development history,typology,and prospective applications of encoding and displayed technologies,including phage display,ribosomal display,mRNA display,yeast cell display,one-bead one-compound,DNA-encoded,peptide nucleic acidencoded,and new peptide-encoded technologies,and examples of preclinical and clinical *** discuss the progress of novel targeted therapeutic agents,covering a spectrum from small-molecule inhibitors and nonpeptidic macrocycles to linear,monocyclic,and bicyclic peptides,in addition to *** also address the pending challenges and future prospects of drug discovery,including the size of screening libraries,advantages and disadvantages of the technology,clinical translational potential,and market *** review is intended to establish a comprehensive high-throughput drug discovery strategy for scientific researchers and clinical drug developers.

关键词： Drug screening Phage display DNA-encoded chemical libraries Peptide-encoded chemical libraries Clinical drugs

Nuclear charge radius predictions by kernel ridge regression with odd-even effects

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Nuclear Science and Techniques 2024年第2期35卷 94-102页

作者： Lu Tang zhen-Hua zhang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The extended kernel ridge regression(EKRR)method with odd-even effects was adopted to improve the description of the nuclear charge radius using five commonly used nuclear *** are:(i)the isospin-dependent A^(1∕3) formula,(ii)relativistic continuum Hartree-bogoliubov(RCHb)theory,(iii)Hartree-Fock-bogoliubov(HFb)model HFb25,(iv)the Weizsacker-Skyrme(WS)model WS*,and(v)HFb25**** the last two models,the charge radii were calculated using a five-parameter formula with the nuclear shell corrections and deformations obtained from the WS and HFb25 models,*** each model,the resultant root-mean-square deviation for the 1014 nuclei with proton number z≥8 can be significantly reduced to 0.009-0.013 fm after considering the modification with the EKRR *** best among them was the RCHb model,with a root-mean-square deviation of 0.0092 *** extrapolation abilities of the KRR and EKRR methods for the neutron-rich region were examined,and it was found that after considering the odd-even effects,the extrapolation power was improved compared with that of the original KRR *** strong odd-even staggering of nuclear charge radii of Ca and Cu isotopes and the abrupt kinks across the neutron N=126 and 82 shell closures were also calculated and could be reproduced quite well by calculations using the EKRR method.

关键词： Nuclear charge radius Machine learning Kernel ridge regression method

Creep-induced redistribution of alloying elements in Cz1 zirconium alloys

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Journal of Materials Science & Technology 2024年第6期173卷 31-44页

作者： W.T.Lin Q.Y.Lv D.Jiao L.b.zhang J.Tan G.Sha J.Hu China Nuclear Power Technology Research Institute Shenzhen 518026China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor alloying elements is an effective strategy to improve the corrosion and mechanical properties of zirconium alloys for nuclear *** in-reactor service,external environment and stress can affect the distribution of alloying elements,substantially changing the degradation process of zirconium *** date,there is a lack of in-depth understanding of the interaction between creep and microchemistry ***,we conducted systematic transmission electron microscopy(TEM)and atom probe tomography(APT)investigations to address creep-induced redistribution of alloying elements in Cz1(zr-Sn-Nb-Fe-Cr-Cu)zirconium alloy with different initial ***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate annealing temperature,the larger the Gibbsian interfacial excesses of solute elements *** further demonstrate that creep can reduce the excess value of Fe at grain boundaries due to the coarsening of zr-Fe-Cr second phase particles via grain boundary and dislocation pipe *** the same time,the excess value of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor element in the concentration range of 0.05-0.3 wt.%is found to segregate at dislocations to form the Cottrell atmosphere and develop Cu-rich nanoclusters for suppressing dislocation *** new understanding of the segregation and clustering of minor alloying elements provides guidance for developing zirconium alloys with enhanced creep resistance.

关键词： zirconium alloy Thermal creep Grain boundary segregation Dislocation segregation Cu-rich nanoclusters

A sponge-based iron-tannic-acid hydrogel interface evaporator designed for clean water production

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Science China(Technological Sciences) 2024年第5期67卷 1579-1591页

作者： zhang zeKun LI ChengLong TAO HuaYu GE bo zhang YongLe zHAO LiMin LIU JunChang REN GuiNa zhang zhaozhu School of Materials Science and Engineering Liaocheng UniversityLiaocheng252059China School of Environmental and Material Engineering Yantai UniversityYantai264405China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

Due to the rapid advancement of technologies,there has been a significant increase in the discharge of industrial wastewater,and freshwater is becoming a scarce ***,research on solar evaporators is mainly focused on the efficient production of clean water,with less emphasis on the removal of residual pollutants remaining in the original *** this study,problems,including the difficult recovery of catalyst powder and the difficult removal of floating organic matter are solved by co-depositing low-surface-tension zirconia particles and bismuth tungstate onto the floating *** and melamine sponges were combined to solve the problem that traditional hydrogels lack mechanical *** excellent water-repellent effect can be seen from the contact angle between the liquid globule and canvas/felt,which is greater than 155°.The steam generation rate of the assembled evaporation system is 1.78 kg m^(-2)h^(-1),and its purification efficiency for methyl orange and rhodamine b exceeds 99%.This study presents a novel strategy for treating wastewater contaminated with organic dyes,aiming to solve problems including environmental damage,water pollution,and water scarcity.

关键词： oil removal non-wetting interface

Tribological properties and tribomechanism of nickel nanoparticles in-situ synthesized in rapeseed oil

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Friction 2024年第3期12卷 474-489页

作者： Wenya XU Guangbin YANG Shengmao zhang Jun XU Yujuan zhang Tianhua SUN Ningning SONG Laigui YU Pingyu zhang Engineering Research Center for Nanomaterials Henan UniversityKaifeng 475004China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Nickel(Ni)nanoparticles can be enriched on the surface of iron-based frictional pairs,which provides the possibility to get rid of the competitive adsorption between the polar species of vegetable oil and the surface-active nano-additives *** this paper,nickel acetylacetonate was used as a precursor to in-situ synthesize nickel nanoparticles with an average diameter of about 12 nm in rapeseed oil(RO)as the reducing agent,surface modifier,and solvent as *** tribological properties of the as-synthesized Ni nanoparticles were evaluated with a four-ball tribometer,and their tribomechanism was investigated based on the characterizations of the tribofilm on rubbed steel surfaces by the scanning electron microscopy(SEM),transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy(XPS).It was found that the Ni nanoparticles in-situ prepared in the RO with a mass fraction of 0.3%can reduce the wear scar diameter(WSD)of the steel ball by 36%.This is because,on the one hand,the Ni nanoparticles are adsorbed on the rubbed steel surfaces to repair or fill up the micro-pits and grooves *** the other hand,Ni nanoparticles participate in tribochemical reactions with atmospheric O and steel substrate to form the tribochemical reaction film on the rubbed steel surfaces with the assistance of friction-induced heat and applied normal *** addition,an amorphous carbon film is formed on the rubbed surface via the carbonization of base oil under the catalysis of Ni *** adsorbed Ni layer,the tribochemical reaction film,and the carbon layer comprise a composite tribofilm composed of amorphous carbon,polar fatty acid,metallic nickel,iron oxides,and nickel oxides on the rubbed steel surfaces,which contributes to significantly improving the antiwear ability and load-carrying capacity of the RO for the steel-steel sliding pair.

关键词： nickel(Ni)nanoparticles rapeseed oil(RO) in-situ synthesis tribological properties tribomechanism

Construction of Phosphorus-Functionalized Multichannel Carbon Interlayers for Dendrite-Free Metallic zn Anodes

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Energy & Environmental Materials 2024年第5期7卷 99-107页

作者： Liang He Qingyin zhang He Li Shiping Liu Ting Cheng Ruoxuan zhang Yujia Wang Peng zhang zhiqiang Shi Tianjin Key Laboratory of Advanced Fibers and Energy Storage School of Materials Science and Engineering Tiangong University Cangzhou Institute of Tiangong University School of Chemical Engineering and Technology Tiangong University Tianjin Lishen battery Joint-Stock CO. LTD

zn metal anodes are usually subject to grave dendrite growth during platting/stripping, which dramatically curtails the lifespan of aqueous zn-ion batteries and capacitors. To address above problems, in our work, a novel phosphorus-functionalized multichannel carbon interlayer was designed and covered on zn anodes. The results demonstrated that the multichannel structure combined with the three-dimensional meshy skeleton can provide more sufficient space for zn deposition, thereby effectively inhibiting the growth of zinc dendrites. Meanwhile, theoretical calculations also confirmed that the P–C and P=O functional groups from phosphorus-functionalized multichannel carbon interlayer have the decisive influence in reducing the zinc nucleation potential and depositing uniformly zinc. Concretely, the symmetrical battery assembled with phosphorus-functionalized multichannel carbon interlayer-covered zn anodes possessed a long lifetime of 3300 h at2 mA cm-2with 1 mAh cm-2. Furthermore, the full cell with activated carbon cathodes exhibited a high specific capacity of 80.5 mAh g-1and outstanding cycling stability without capacity decay after 15 000 cycles at a high current density of 5 A g-1. The superior electrochemical performance exceeded that of most reported papers. Consequently, our synthesized zincophilic interlayer with the unique structure has superior prospects for application in stabilizing zinc anodes and prolonging the lifespan of batteries.

关键词： aqueous zn-ion supercapacitors multichannel carbon fiber phosphorus functionalized zn dendrite zn metal anode