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Artificial molecular machines:Design and observation 被引量:4
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作者 Shu Zhang Yi An +1 位作者 Xu-man Chen Quan Li 《Smart Molecules》 2023年第3期1-21,共21页
Natural molecular machines have inspired the development of artificial molecular machines,which have the potential to revolutionize several areas of technology.Artificial molecular machines commonly employ molecular s... Natural molecular machines have inspired the development of artificial molecular machines,which have the potential to revolutionize several areas of technology.Artificial molecular machines commonly employ molecular switches,molecular motors,and molecular shuttles as fundamental building blocks.The observation of artificial molecular machines constructed by these building blocks can be highly challenging due to their small sizes and intricate behaviors.The use of modern instrumentation and advanced observational techniques plays a crucial role in the observation and characterization of molecular machines.Furthermore,a well-designed molecular structure is also a critical factor in making molecular ma-chines more observable.This review summarizes the common methods from diverse perspectives used to observe molecular machines and emphasizes the significance of comprehending their behaviors in the design of superior artificial molecular machines. 展开更多
关键词 artificial molecular machines mechanically interlocked molecules molecular motors molecular switches supramolecular chemistry
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Collective Molecular Machines: Multidimensionality and Reconfigurability
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作者 Bin Wang Yuan Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期309-340,共32页
Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generat... Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research.Effective progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and informatics.However,individual molecular machines are only capable of producing nanometer work and generally have only a single functionality.In order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm.In this review,we comprehensively discuss recent developments in the collective behaviors of molecular machines.In particular,collective behavior is divided into two paradigms.One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials.The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations.We discuss design strategies for both modes and focus on the modulation of features and properties.Subsequently,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines. 展开更多
关键词 molecular machines Collective control Collective behaviors DNA Biomolecular motors
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A large-scale on-the-fly machine learning molecular dynamics simulation to explore lithium metal battery interfaces
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作者 Yi-Lin Niu Xiang Chen +5 位作者 Tian-Chen Zhang Yu-Chen Gao Yao-Peng Chen Nan Yao Zhong-Heng Fu Qiang Zhang 《Journal of Energy Chemistry》 2025年第11期356-362,I0010,共8页
The global rapid transition towards sustainable energy systems has heightened the demand for highperformance lithium metal batteries(LMBs),where understanding interfacial phenomena is paramount.In this contribution,we... The global rapid transition towards sustainable energy systems has heightened the demand for highperformance lithium metal batteries(LMBs),where understanding interfacial phenomena is paramount.In this contribution,we present an on-the-fly machine learning molecular dynamics(OTF-MLMD)approach to probe the complex side reactions at lithium metal anode–electrolyte interfaces with exceptional accuracy and computational efficiency.The machine learning force field(MLFF)was firstly validated in a bulk-phase system comprising twenty 1,2-dimethoxyethane(DME)molecules,demonstrating energy fluctuations and structural parameters in close agreement with ab initio molecular dynamics(AIMD)benchmarks.Subsequent simulations of lithium–DME and lithium–electrolyte interfaces revealed minimal discrepancies in energy,bond lengths,and net charge variations(notably in FSI-species),underscoring the method's DFT-level precision of the approach.A further small-scale interfacial model enabled on-the-fly training over a mere of 340 fs,which was then successfully transferred to a large-scale simulation encompassing nearly 300,000 atoms,representing the largest interfacial model in LMB research up to date.The hierarchical validation strategy not only establishes the robustness of the MLFF in capturing both interfacial and bulk-phase chemistry but also paves the way for statistically meaningful simulations of battery interfaces.The fruitful findings highlight the transformative potential of OTF-MLMD in bridging the gap between atomistic accuracy and macroscopic modeling,affording a universal approach to understand interfacial reactions in LMBs. 展开更多
关键词 Lithium metal batteries Liquid electrolytes Interfacial reactions On-the-fly machine learning molecular dynamics Large-scale simulations
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Artificial molecular machines that can perform work 被引量:5
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作者 Qiaochun Wang Dizhi Chen He Tian 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第10期1261-1273,共13页
An artificial molecular machine consists of molecule or substituent components jointed together in a specific way so that their mutual displacements could be initiated using appropriate outside stimuli. Such an abilit... An artificial molecular machine consists of molecule or substituent components jointed together in a specific way so that their mutual displacements could be initiated using appropriate outside stimuli. Such an ability of performing mechanical motions by consuming external energy has endowed these tiny machines with vast fascinating potential applications in areas such as actuators, manipulating atoms/molecules, drug delivery, molecular electronic devices, etc. To date, although vast kinds of molecular machine archetypes have been synthesized in facile ways, they are inclined to be defined as switches but not true machines in most cases because no useful work has been done during a working cycle. More efforts need to be devoted on the utilization and amplification of the nanoscale mechanical motions among synthetic molecular machines to accomplish useful tasks. Here we highlight some of the recent advances relating to molecular machines that can perform work on different length scales, ranging from microscopic levels to macroscopic ones. 展开更多
关键词 molecular machines molecular motors ROTAXANES CATENANES switches
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Artificial muscles driven by the cooperative actuation of electrochemical molecular machines.Persistent discrepancies and challenges
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作者 Toribio Fernández Otero 《International Journal of Smart and Nano Materials》 SCIE EI 2017年第4期125-143,共19页
Here we review the persisting conceptual discrepancies between different research groups working on artificial muscles based on conducting polymers and other electroactive material.The basic question is if they can be... Here we review the persisting conceptual discrepancies between different research groups working on artificial muscles based on conducting polymers and other electroactive material.The basic question is if they can be treated as traditional electro-mechanical(physical)actuators driven by electric fields and described by some adaptation of their physical models or if,replicating natural muscles,they are electro-chemo-mechanical actuators driven by electrochemical reaction of the constitutive molecular machines:the polymeric chains.In that case the charge consumed by the reaction will control the volume variation of the muscular material and the motor displacement,following the basic and single Faraday’s laws:the charge consumed by the reaction determines the number of exchanged ions and solvent,the film volume variation to lodge/expel them and the amplitude of the movement.Deviations from the linear relationships are due to the osmotic exchange of solvent and to the presence of parallel reactions from the electrolyte,which originate creeping effects.Challenges and limitations are underlined. 展开更多
关键词 Electromechanical actuator electro-chemo-mechanical artificial muscle molecular machines CREEPING osmotic effects
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Recent advances in molecular machines based on toehold-mediated strand displacement reaction
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作者 Yijun Guo Bing Wei +6 位作者 Shiyan Xiao Dongbao Yao Hui Li Huaguo Xu Tingjie Song Xiang Li Haojun Liang 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2017年第1期25-41,共17页
Background: The DNA strand displacement reaction, which uses flexible and programmable DNA molecules as reaction components, is the basis of dynamic DNA nanotechnology, and has been widely used in the design of compl... Background: The DNA strand displacement reaction, which uses flexible and programmable DNA molecules as reaction components, is the basis of dynamic DNA nanotechnology, and has been widely used in the design of complex autonomous behaviors. Results: In this review, we first briefly introduce the concept of toehold-mediated strand displacement reaction and its kinetics regulation in pure solution. Thereafter, we review the recent progresses in DNA complex circuit, the assembly of AuNPs driven by DNA molecular machines, and the detection of single nucleotide polymorphism (SNP) using DNA toehold exchange probes in pure solution and in interface state. Lastly, the applications of toehold-mediated strand displacement in the genetic regulation and silencing through combining gene circuit with RNA interference systems are reviewed. Conclusions: The toehold-mediated strand displacement reaction makes DNA an excellent material for the fabrication of molecular machines and complex circuit, and may potentially be used in the disease diagnosis and the regulation of gene silencing in the near future. 展开更多
关键词 toehold-mediated strand displacement DNA molecular machines SNP gene expression regulation
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Molecular insight into the GaP(110)-water interface using machine learning accelerated molecular dynamics 被引量:1
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作者 Xue-Ting Fan Xiao-Jian Wen +1 位作者 Yong-Bin Zhuang Jun Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期239-247,I0006,共10页
GaP has been shown to be a promising photoelectrocatalyst for selective CO_(2)reduction to methanol.Due to the relevance of the interface structure to important processes such as electron/proton transfer,a detailed un... GaP has been shown to be a promising photoelectrocatalyst for selective CO_(2)reduction to methanol.Due to the relevance of the interface structure to important processes such as electron/proton transfer,a detailed understanding of the GaP(110)-water interfacial structure is of great importance.Ab initio molecular dynamics(AIMD)can be used for obtaining the microscopic information of the interfacial structure.However,the GaP(110)-water interface cannot converge to an equilibrated structure at the time scale of the AIMD simulation.In this work,we perform the machine learning accelerated molecular dynamics(MLMD)to overcome the difficulty of insufficient sampling by AIMD.With the help of MLMD,we unravel the microscopic information of the structure of the GaP(110)-water interface,and obtain a deeper understanding of the mechanisms of proton transfer at the GaP(110)-water interface,which will pave the way for gaining valuable insights into photoelectrocatalytic mechanisms and improving the performance of photoelectrochemical cells. 展开更多
关键词 PHOTOELECTROCATALYSIS GaP(110)-water interface machine learning accelerated molecular dynamics
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Parallel Molecular Dynamics on the Connection Machines 被引量:1
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作者 Daniel I. Okunbor 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期337-343,共7页
Abstract Abstract:We have demonstrated using vectorized parallel Lennard-Jones fluid program that vectorizing general-purpose parallel molecular package for simulating biomolecules which currently runs on the Connect... Abstract Abstract:We have demonstrated using vectorized parallel Lennard-Jones fluid program that vectorizing general-purpose parallel molecular package for simulating biomolecules which currently runs on the Connection Machine CM-5 using CMMD message passing would offer a significant improvement over 4 non-vectorized version. Our results indicate that the Lennard-Jones fluid program written in C*/CMNID is five times faster than the same program written in C/CMMD. 展开更多
关键词 Parallel molecular Dynamics on the Connection machines
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Pillar[5]arene-based [3]rotaxanes: Convenient construction via multicomponent reaction and pH responsive self-assembly in water 被引量:1
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作者 Junmei Ye Runmiao Zhan +5 位作者 Wenjuan Yang Ying Han Hao Guo Ju Xie Chaoguo Yan Yong Yao 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第6期1550-1553,共4页
Four pillar[5]arene based[3]rotaxanes(1-4)involving two 1,4-diethoxypillar[5]arene(DEP5)rings and a dumbbell-shaped component were successfully synthesized.The dumbbell-shape molecules contain one longer bridge,two tr... Four pillar[5]arene based[3]rotaxanes(1-4)involving two 1,4-diethoxypillar[5]arene(DEP5)rings and a dumbbell-shaped component were successfully synthesized.The dumbbell-shape molecules contain one longer bridge,two triazole sites and two multicomponent stoppers.After threading DEP5 rings with linear vips(G1-G4)which contain two benzaldehyde units,the base catalyzed three-component reaction of dimedone,malononitrile and benzaldehyde was performed to construct the stoppers and connected the pseudorotaxanes with stoppers to generate 1-4.The structures of[3]rotaxanes and their self-assembly behaviors were characterized by 1 H NMR,13C NMR,NOESY,HR-ESI-MS,DLS and TEM technologies.We hope that pillar[5]arene based[3]rotaxanes may have potential applications in drug delivery systems and molecular devices. 展开更多
关键词 arene Rotaxane Multicomponent reaction molecular machine SELF-ASSEMBLY
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Mono-functionalized pillar[n]arenes: Syntheses, host–vip properties and applications 被引量:1
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作者 Wenzhi Yang Wenjie Zhang +1 位作者 Jingyu Chen Jiong Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期16-30,共15页
Pillar[n]arenes are a novel class of macrocyclic hosts reported by Ogoshi and co-workers in 2008. Because of their rigid pillar structures, interesting host-vip properties and ease of modifications, pillar[n]arenes ... Pillar[n]arenes are a novel class of macrocyclic hosts reported by Ogoshi and co-workers in 2008. Because of their rigid pillar structures, interesting host-vip properties and ease of modifications, pillar[n]arenes have been developed rapidly in the field of functional materials and biomedicine. The modifications of pillar[n]arenes at different positions can give them varied characteristics. Functional groups can be introduced into one position of pillar[n]arenes without changing host-vip properties of pillar[n]arenes. A series of pillar[n]arene dimers, trimers, tetramers and metallacycles can be constructed by mono-functionalized pillar[n]arenes. In this review, two synthetic methods of mono-functionalized pillar[n]arenes are summarized and structures containing mono-functionalized pillar[n]arenes are described. Furthermore, the applications of mono-functionalized pillar[n]arenes in different fields (e.g., supramolecular polymers, sensors, molecular machines, catalysis, biological applications and light-harvesting systems) are also introduced. Hopefully, this article will be useful for researchers studying pillar[n]arenes, especially the mono-functionalized pillar[n]arenes. 展开更多
关键词 Pillar[n]arenes Host-vip properties Supramolecular polymer molecular machines Biological application
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Thermomechanical Energy Converters for Harvesting Thermal Energy:A Review
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作者 Oleg P.Dimitriev 《Journal of Renewable Materials》 SCIE EI 2023年第4期1555-1600,共46页
Thermal energy,i.e.,the electromagnetic energy in the infrared range that originates from the direct solar radiation,outgoing terrestrial radiation,waste heat from combustion of fuels,heat-emitting electrical devices,... Thermal energy,i.e.,the electromagnetic energy in the infrared range that originates from the direct solar radiation,outgoing terrestrial radiation,waste heat from combustion of fuels,heat-emitting electrical devices,decay of radioactive isotopes,organic putrefaction and fermentation,human body heat,and so on,constitutes a huge energy flux circulating on the earth surface.However,most energy converters designed for the conversion of electromagnetic energy into electricity,such as photovoltaic cells,are mainly focused on using a narrow part of the solar energy lying in the visible spectrum,while thermomechanical engines that are fueled by heat in the broad energy range and then convert it into mechanical work or store it as mechanical deformation,are paid less attention.Although the efficiency of thermomechanical devices is relatively low,they can be applied to collect waste heat which otherwise contributes to negative climate changes.In this review,operational principles of thermomechanical energy converters and a description of basic devices and materials that utilize thermal energy are given.In addition to conventional macroscopic engines,based on thermoacoustic,thermomagnetic,thermoelastic,hydride heat converters,and shape memory alloys,the emergent devices are described which are classified as smart actuators,breathing frameworks,thermoacoustic micro-transducers,nanomechanical resonators,plasmomechanical systems,and optothermal walkers.The performance of the different types of thermomechanical energy converters is described and compared. 展开更多
关键词 Thermal energy smart actuator thermomechanical converter thermoelastic engine molecular machines emergent devices
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Water structures and anisotropic dynamics at Pt(211)/water interface revealed by machine learning molecular dynamics
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作者 Fei-Teng Wang Xiandong Liu Jun Cheng 《Materials Futures》 2024年第4期1-10,共10页
Water molecules at solid–liquid interfaces play a pivotal role in governing interfacial phenomena that underpin electrochemical and catalytic processes.The organization and behavior of these interfacial water molecul... Water molecules at solid–liquid interfaces play a pivotal role in governing interfacial phenomena that underpin electrochemical and catalytic processes.The organization and behavior of these interfacial water molecules can significantly influence the solvation of ions,the adsorption of reactants,and the kinetics of electrochemical reactions.The stepped structure of Pt surfaces can alter the properties of the interfacial water,thereby modulating the interfacial environment and the resulting surface reactivity.Revealing the in situ details of water structures at these stepped Pt/water interfaces is crucial for understanding the fundamental mechanisms that drive diverse applications in energy conversion and material science.In this work,we have developed a machine learning potential for the Pt(211)/water interface and performed machine learning molecular dynamics simulations.Our findings reveal distinct types of chemisorbed and physisorbed water molecules within the adsorbed layer.Importantly,we identified three unique water pairs that were not observed in the basal plane/water interfaces,which may serve as key precursors for water dissociation.These interfacial water structures contribute to the anisotropic dynamics of the adsorbed water layer.Our study provides molecular-level insights into the anisotropic nature of water behavior at stepped Pt/water interfaces,which can influence the reorientation and distribution of intermediates,molecules,and ions—crucial aspects for understanding electrochemical and catalytic processes. 展开更多
关键词 machine learning molecular dynamics stepped Pt/water interfaces anisotropic water dynamics
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Thermal Energy-Driven Solid-State Molecular Rotation Monitored by Real-Time Emissive Color Switching 被引量:4
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作者 Junfeng Li Chenxi Hou +6 位作者 Qi Qi Lin Jiao Lanqing Dai Dong Chen Haigang Geng Wen-Yong Lai Wei Huang 《CCS Chemistry》 CAS 2022年第8期2711-2723,共13页
Inspired by nature’s molecular machines,the scientific research on solid-state molecular rotors is of great interest yet remains largely unexplored.Herein,we report a unique example of a thermal energydriven stimuli-... Inspired by nature’s molecular machines,the scientific research on solid-state molecular rotors is of great interest yet remains largely unexplored.Herein,we report a unique example of a thermal energydriven stimuli-responsive solid-state molecular rotor,which features an o-carborane moiety as a rotor that directly transduces the surrounding thermal energy into molecular rotations in the crystalline state.Its rotation is confirmed by X-ray diffraction. 展开更多
关键词 molecular machines molecular rotation CARBORANE twisted intramolecular charge transfer emission emissive color switching
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[c2]Daisy Chain Rotaxanes as Molecular Muscles 被引量:4
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作者 Antoine Goujon Emilie Moulin +1 位作者 Gad Fuks Nicolas Giuseppone 《CCS Chemistry》 CAS 2019年第1期83-96,共14页
Bistable[c2]daisy chain rotaxanes represent a par-ticularly intriguing class of interlocked molecules that can produce internal sliding movements with a net contraction or extension at the single-molecule level.
关键词 molecular machines supramolecular chemistry POLYMERS responsive materials
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Fluorescent Linear Supramolecular Polymer Based on Host-vip Interactions 被引量:1
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作者 Chenxiao Xiong Ruyi Sun 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第11期1669-1672,共4页
Construction of supramolecular polymers, in which functional monomer components are held together by non- covalent interactions, is considered as a promising design principle for functional materials. Linear fluoresce... Construction of supramolecular polymers, in which functional monomer components are held together by non- covalent interactions, is considered as a promising design principle for functional materials. Linear fluorescent su- pramolecular polymer assembled on account of electrostatic attractions based host-vip interaction is synthesized and illustrated here. 1H NMR was involved to ensure the structure of vip and polymer, UV-vis and fluorescent spectra were recorded to be a readout signal to investigate the assemble process of polymer. TEM and AFM meas- urements were carried out to confirm the homogeneous nanometer-sized molecular assembly. It shows the way to be used as remote readout fluorescent functional material in the future. 展开更多
关键词 supramolecular polymer stimuli responsive molecular machines functional material
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Single-Molecule Studies on Artificial Small-Molecule Machines 被引量:1
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作者 Zhi-Hui Zhang Hai-Na Feng +2 位作者 Guanyu Chi David A.Leigh Liang Zhang 《CCS Chemistry》 CSCD 2023年第11期2448-2465,共18页
Molecular machines transduce energy from one form to another through controlled motion in response to stimuli.Despite the ubiquitous use of molecular machines in biology,understanding the detailed mechanisms of such c... Molecular machines transduce energy from one form to another through controlled motion in response to stimuli.Despite the ubiquitous use of molecular machines in biology,understanding the detailed mechanisms of such complex structures remains challenging.Recent progress in studying the modes of operation of synthetic small-molecule machines at the single-molecule level has shed new light on the mechanisms of nano-machinery.In this mini-review,we focus on the study of artificial small-molecule machines using single-molecule techniques,including single-molecule force spectroscopy,single-molecule electrical spectroscopy,and single-molecule optical spectroscopy.We survey the techniques used to monitor single-molecule behavior to date and describe the latest studies on small-molecule machines,highlighting their common features and challenges that need to be overcome to realize the potential of these techniques in unraveling the behavior of small molecule systems. 展开更多
关键词 artificial molecular machines singlemolecule techniques molecular nanotechnology
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The supramolecular redox functions of metallomacromolecules 被引量:2
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作者 Didier Astruc 《Journal of Leather Science and Engineering》 2020年第1期129-145,共17页
Metallomacromolecules are frequently encountered in redox proteins including metal-tanned hide collagen and play crucial roles involving supramolecular properties in biological electron-transfer processes.They are als... Metallomacromolecules are frequently encountered in redox proteins including metal-tanned hide collagen and play crucial roles involving supramolecular properties in biological electron-transfer processes.They are also currently found in non-natural families,such as:metallopolymers,metallodendrimers and metallodendronic polymers.This mini-review discusses the supramolecular redox functions of such nanomaterials developed in our research group.Electron-transfer processes are first examined in mono-,bis-and hexa-nuclear ferrocenes and other electron-reservoir organoiron systems showing the influence of supramolecular and reorganization aspects on their mechanism.Then applications of electron-transfer processes using these same organoiron redox systems in metallomacromolecules and their supramolecular functions are discussed including redox recognition/sensing,catalysis templates,electrocatalysis,redox catalysis,molecular machines,electrochromes,drug delivery device and nanobatteries. 展开更多
关键词 FERROCENE electron reservoir Polymer DENDRIMER Redox catalyst Redox sensor molecular machine Supramolecular template Electrochrome Drug delivery device Battery
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Molecular rotors as a class of generally highly active ion transporters
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作者 Jie Shen Joan Jia Ying Han +1 位作者 Ruijuan Ye Huaqiang Zeng 《Science China Chemistry》 SCIE EI CSCD 2021年第12期2154-2160,共7页
We describe here a class of unconventional ion transporters,molecular rotors that transport ions through a rotating function rather than via traditional carrier or channel mechanisms.Mimicking macroscopic rotors,these... We describe here a class of unconventional ion transporters,molecular rotors that transport ions through a rotating function rather than via traditional carrier or channel mechanisms.Mimicking macroscopic rotors,these molecular rotors consist of three modularly tunable components,i.e.,a membrane-anchoring stator,a crown ether-containing rotator for ion binding and transport,and a triple bond-based axle that allows the rotator to freely rotate around the stator in the lipid membrane.Lipid bilayer experiments reveal the generally high ability of all molecular rotors in promoting the highly efficient transmembrane K^(+)flux(EC50 values=0.49-1.37 mol%relative to lipid).While molecular rotors differing only in the ion-binding unit exhibit similar ion transport activities,those differing in the rotator’s length display activity differences by up to 174%. 展开更多
关键词 supramolecular chemistry molecular machines artificial membrane transporters molecular rotors K+transporters
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Seeing Is Believing:Directly Imaging Contractions of Artificial Molecular Muscles with Platinum Atom Markers
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作者 Dan-Yang Zhang Yonghui Zheng +5 位作者 Yefei Jiang Wei-Jian Li Xu-Qing Wang Lianrui Hu Wei Wang Hai-Bo Yang 《CCS Chemistry》 CSCD 2024年第9期2162-2174,共13页
Artificial molecular muscles undergo well-controlled contractile and extensile motions upon external stimulation,leading to remarkable length changes.Evaluating such length changes at the molecular level is essential ... Artificial molecular muscles undergo well-controlled contractile and extensile motions upon external stimulation,leading to remarkable length changes.Evaluating such length changes at the molecular level is essential to the design of integrated artificial molecular muscles that mimic biological muscles.Taking advantage of the strong contrast of platinum(Pt)atoms in high-angle annular dark-field scanning transmission electron microscopy images,we imaged Pt-containing molecular[c2]daisy chains directly by employing metal atom markers.The length changes and associated conformational transformations of these newly developed artificial molecular muscles have been measured experimentally in combination with theoretical calculations.The contraction ratios of these two molecular muscles with the TEMPO or pyrene anchoring group were calculated to be 21.0%or 15.7%respectively,suggesting a substantial anchoring effect.This study demonstrates the experimental measurement of the length changes of artificial molecular muscles and provides a new avenue for investigating the motion of artificial molecular machines. 展开更多
关键词 mechanically interlocked molecules molecular[c2]daisy chain artificial molecular machines high-angle annular dark-field scanning transmission electron microscopy stimuli responsiveness
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Research on the nanometric machining of a single crystal nickel via molecular dynamics simulation 被引量:4
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作者 GONG Ya Dong ZHU Zong Xiao +1 位作者 ZHOU Yun Guang SUN Yao 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第12期1837-1846,共10页
Molecular dynamics simulations are employed to study the nanometric machining process of single crystal nickel. Atoms from different machining zones had different atomic crystal structures owing to the differences in ... Molecular dynamics simulations are employed to study the nanometric machining process of single crystal nickel. Atoms from different machining zones had different atomic crystal structures owing to the differences in the actions of the cutting tool. The stacking fault tetrahedral was formed by a series of dislocation reactions, and it maintained the stable structure after the dislocation reactions. In addition, evidence of crystal transition and recovery was found by analyzing the number variations in different types of atoms in the primary shear zone, amorphous region, and crystalline region. The effects of machining speed on the cutting force, chip and subsurface defects, and temperature of the contact zone between the tool and workpiece were investigated. The results suggest that higher the machining speed, larger is the cutting force. The degree of amorphousness of chip atoms and the depth and extent of subsurface defects increase with the machining speed. The average friction coefficient first decreases and then increases with the machining speed because of the temperature difference between the chip and machining surface. 展开更多
关键词 molecular dynamics simulation nanometric machining single crystal nickel crystal transition and recovery machining speed
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