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Magnetic Resonance Letters 2024年第3期4卷 35-41页

作者： Zhiwei Yan Yue-Qi Ye Rongchun Zhang South China Advanced Institute for soft matter Science and Technology(AISMST) School of Emergent Soft Matter(SESM)South China University of TechnologyGuangzhou510640China JEOL(Beijing)Co. Ltd.Haidian DistrictBeijing100190China JEOL Ltd. MusashinoAkishimaTokyo196-8558Japan Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

INADEQUATE(Incredible Natural Abundance DoublE QUAntum Transfer Experiment)is one of the most important techniques in revealing the carbon skeleton of organic solids in solid-state NMR ***,its use for structural analysis is quite limited due to the low natural abundance of^(13)C-^(13)C connectivity(~0.01%)and thus low ***,in semi-solids like rubbers,the sensitivity will be further significantly reduced by the inefficient cross polarization from 1H to^(13)C due to molecular motions induced averaging of^(1)H-^(13)C dipolar ***,in this study,we demonstrate that transient nuclear Overhauser effect(NOE)can be used to efficiently enhance^(13)C signals,and thus enable rapid acquisition of two-dimensional(2D)^(13)C INADEQUATE spectra of *** chlorobutyl rubber as the model system,it is found that an overall signalto-noise ratio(SNR)enhancement about 22%can be achieved,leading to significant timesaving by about 33%as compared to the direct polarization-based INADEQUATE *** experimental results on natural rubber and ethylene propylene diene monomer(EPDM)rubber are also shown to demonstrate the robust performance of transient NOE enhanced INADEQUATE experiment.

关键词： Transient NOE INADEQUATE Carbon skeleton Rubbers

Double stimulus-responsive palladium catalysts for ethylene polymerization and copolymerization

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Chinese Chemical Letters 2024年第7期35卷 407-411页

作者： Hailong He Wenbing Wang Wenmin Pang Chen Zou Dan Peng CAS Key Laboratory of soft matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei National Laboratory for Physical Sciences at the MicroscaleHefei 230026China

The external stimulus response strategy has been evolved rapidly in the field of olefin *** this work,we modularly synthesized three types of double stimulus responsiveα-diimine palladium catalysts,combining redox regulation and other regulation together,such as light,Lewis acid and alkali *** catalytic activities and the molecular weight of polyethylene products can be regulated for 4 times in ethylene *** palladium complexes were also used for the copolymerization reaction of ethylene and polar monomers,such as methyl 10-undecylenate and methyl acrylate,effectively regulating the catalytic activities,the molecular weight and polar monomer incorporation of the prepared *** research on these dual-regulated palladium complexes makes full use of prepared catalysts and provides new inspirations for regulating olefin polymerization.

关键词： Dual-regulated Stimulus-responsive Palladium Ethylene polymerization Polar monomer

Spatial structure regulation towards armor-clad five-membered pyrroline nitroxides catholyte for long-life aqueous organic redox flow batteries

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eScience 2024年第1期4卷 143-151页

作者： Hao Fan Kai Liu Xudong Zhang Yunpeng Di Pan Liu Jiaqi Li Bo Hu Hongbin Li Mahalingam Ravivarma Jiangxuan Song State Key Laboratory for Mechanical Behavior of Materials Shaanxi International Research Center for Soft MatterSchool of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China Network Information Center Xi'an Jiaotong UniversityXi'an 710049China

Five-membered pyrroline nitroxides with high-potential is fascinating as catholyte for aqueous organic redox flow batteries(AORFBs),however,it suffers from a primary deficiency of insufficient stability due to ring-opening side *** we report a spatial structure regulation strategy by host-guest chemistry,encapsulating 3-carbamoyl-2,2,5,5-tetramethylpyrroline-1-oxyl(CPL)into hydrosoluble cyclodextrins(CDs)with an inclusion structure of N–O⋅head towards cavity bottom,to boost the solubility and cyclability of pyrroline nitroxides *** armor-clad CPL(CPL⊂HP-β-CD)catholyte in 0.05–0.5 M presents a battery capacity fade rate as low as 0.002%/cycle(0.233%/day)compared to the sole CPL in 0.05 M(0.039%/cycle or 5.23%/day)over 500 cycles in assembled *** optimized reclining spatial structure with N–O⋅head towards CD cavity bottom effectively inhibits the attack of Lewis base species on the hydrogen abstraction site in pyrroline ring,and thus avoids the ring-opening side reaction of pyrroline nitroxides.

关键词： Aqueous organic redox flow batteries Stabilization mechanism Spatial structure Five-membered pyrroline nitroxides Cyclodextrins

Spontaneous unidirectional rotation of a symmetric gear driven by spherical active particles

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National Science Open 2024年第4期3卷 41-53页

作者： Chao Wang Wenchao Lian Huishu Li Wende Tian Kang Chen Center for soft Condensed matter Physics & Interdisciplinary research School of Physical Science and Technology Soochow University school of Physics and Electronic Engineering Linyi University

Time reversal asymmetry and spatial anisotropy are considered two prerequisites for Brownian ratchet. An intriguing realization can be achieved by placing an asymmetric gear in the suspension of motile rod-like bacteria. Usually,alignment interactions caused by anisotropic collisions or hydrodynamics would boost the ratchet effect. Here, we are concerned with a perfectly isotropic system, i.e., symmetric gear immersed in a bath of spherical active Brownian particles. We find that, under certain conditions, kinetic symmetry-breaking arises spontaneously, i.e., the symmetric gear keeps rotating in one direction. Unexpectedly, such ratchet phenomenon does not rely on the direct many-particle interactions and moreover the introduction of alignment interaction would counterintuitively prevent it from happening! Further investigation reveals that such spontaneous symmetry-breaking phenomenon shares similarities with the equilibrium phase transition of the Ising *** results provide new insights and enhance our understanding of the fundamental aspects of active ratchet phenomena.

关键词： ratchet effect spontaneous symmetry breaking active brownian particles ising model hysteresis

Health risks and sources of trace elements and black carbon in PM_(2.5)from 2019 to 2021 in Beijing

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Journal of Environmental Sciences 2024年第8期142卷 69-82页

作者： Chenjie Hua Wei Ma Feixue Zheng Yusheng Zhang Jiali Xie Li Ma Boying Song Chao Yan Hongyan Li Zhen Liu Qian Liu Markku Kulmala Yongchun Liu Aerosol and Haze Laboratory Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Institute for Atmospheric and Earth System research Faculty of ScienceUniversity of HelsinkiHelsinki 00014Finland school of Environment and Safety Taiyuan University of Science and TechnologyTaiyuan 030024China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

A comprehensive health risk assessment of PM_(2.5)is meaningful to understand the current status and directions regarding further improving air quality from the perspective of human *** this study,we evaluated the health risks of PM_(2.5)as well as highly toxic inorganic components,including heavy metals(HMs)and black carbon(BC)based on longterm observations in Beijing from 2019 to *** results showed that the relative risks of chronic obstructive pulmonary disease,lung cancer,acute lower respiratory tract infection,ischemic heart disease,and stroke decreased by 4.07%-9.30%in 2020 and 2.12%-6.70%in2021 compared with ***,they were still at high levels ranging from 1.26 to 1.77,in particular,stroke showed the highest value in *** had the highest hazard quotient(HQ,from 2.18 to 2.56)for adults from 2019 to 2021,while Ni,Cr,Pb,As,and BC showed high carcinogenic risks(CR>1.0×10^(-6))for *** HQ values of Mn and As and the CR values of Pb and As showed constant or slight upwards trends during our observations,which is in contrast to the downward trends of other HMs and PM_(2.5).Mn,Cr,and BC are crucial toxicants in PM_(2.5).A significant shrink of southern region sourcesof HMs and BCshrank suggests the increased importance of local ***,dust,and biomass burning are the major contributors to the non-carcinogenic risks,while traffic emissions and industry are the dominant contributors to the carcinogenic risks in Beijing.

关键词： PM_(2.5) Heavy metals Black carbon Health risk Source apportionment

Mechanically robust and dynamic supramolecular polymer networks enabled by [an]daisy chain backbones

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Science China Chemistry 2024年

作者： Yongming Wang Yi Ding Yuhang Liu Shaolei Qu Wenbin Wang Wei Yu Zhaoming Zhang Feng Liu Xuzhou Yan school of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules Shanghai Jiao Tong University State Key Laboratory for Mechanical Behavior of Materials Shaanxi International Research Center for Soft Matter School of Materials Science and Engineering Xi'an Jiaotong University

Supramolecular polymer networks（SPNs） have garnered significant research interest due to their dynamic properties. However,while current developments primarily focus on managing supramolecular crosslinks, the role of polymer backbones—equally crucial to SPN properties—has not yet been sufficiently explored. Herein, we utilize mechanically interlocked [an]daisy chain as backbone to prepare a class of SPNs, where the force-induced motion of successive mechanical bonds toughens and reinforces the networks. In specific, the [an]daisy chain backbones connect with polynorbornene chains through quadruple H-bonding in the SPN networks. Compared to the control with non-slidable backbone, The representative SPN-2 exhibits a robust feature in tensile tests with high maximum stress（14.7 vs. 7.89 MPa） and toughness（83.8 vs. 48.6 MJ/m3）. Moreover, it also has superior performance in energy dissipation benefitting from the [an]daisy chain backbones as well as supramolecular crosslinks. Additionally, the SPN-2 displayed exceptional self-healing and reprocessing capabilities due to their dynamic quadrable H-bonding crosslinkers. These findings demonstrate the untapped potential of [an]daisy chain as a polymer skeleton to develop SPNs and open the door to design mechanically robust supramolecular materials with diverse smart functions.

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A non-antibiotic organic coating on ZA6-1 surface releasing different concentrations of sodium dodecyl sulphate/levulinic acid for orthopaedic application

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Biosurface and Biotribology 2024年第2期10卷 42-51页

作者： Feng Zou Deren Zhao Yangkai Liu Qiqi Lu Hulin Liu Zilin Chen Yaxing Fang Xiaodong Tan Yunjie Xiang Xue Feng Yongping Zhang Xi Rao school of Materials and Energy Southwest UniversityChongqingChina Chongqing Key Laboratory of soft-matter Material Chemistry and Function Manufacturing Southwest UniversityChongqingChina Department of Clinical Laboratory University-Town Hospital of Chongqing Medical UniversityChongqingChina

Bone implantation surgery is often accompanied by bacterial infection,resulting in infectious bone non-union,pathological fracture and other serious consequences,which will aggravate the pain of patients.A non-antibiotic coating consisting of sodium dodecyl sulphate(SDS)and levulinic acid(LA)with different concentrations was prepared by the authors on the zinc–aluminium alloy(ZA6-1)using a wet chemistry treatment for orthopaedic *** influence of SDS/LA concentrations on the surface morphology,composition and performance of the developed coating was *** results showed that as-prepared coating on a zinc alloy surface could improve the substrate's corrosion resistance and increase the degradation rate from 0.82 to 19.70μm/year upon raising the SDS/LA ***,higher hydrophilicity(100%)and morphology,as well as good cell adhesion and differentiation(ALP>95%for 7 days)were observed on coated zinc *** increased SDS/LA concentration slightly weakens the biocompatibility and enhances the antibacterial performance of coated zinc alloys due to the synergistic effect of SDS/***,the coating comprising 6 wt.%SDS and 9 wt.%LA showed excellent antibacterial action with a high level of biocompatibility,confirming its potential application for orthopaedic implants.

关键词： antibacterial biocompatibility biomaterials material property

Dzyaloshinskii–Moriya interaction and field-free sub-10 nm topological magnetism in Fe/bismuth oxychalcogenides heterostructures

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Chinese Physics B 2024年第9期33卷 200-206页

作者： Yaoyuan Wang Long You Kai Chang Hongxin Yang school of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074China Center for Quantum matter School of PhysicsZhejiang UniversityHangzhou 310058China Shenzhen Huazhong University of Science and Technology research Institute Shenzhen 518000China

Topological magnetism with strong robustness,nanoscale dimensions and ultralow driving current density(106 A/m^(2))is promising for applications in information sensing,storage,and processing,and thus sparking widespread research *** candidate material systems with nanoscale size and easily tunable properties is a key for realizing practical topological magnetism-based spintronic ***,we propose a class of ultrathin heterostructures,Fe/Bi_(2)O_(2)X(X=S,Se,Te)by deposing metal Fe on quasi-two-dimensional(2D)bismuth oxychalcogenides Bi_(2)O_(2)X(X=S,Se,Te)with excellent ferroelectric/ferroelastic *** Dzyaloshinskii–Moriya interaction(DMI)and topological magnetism can be *** atomistic spin dynamics simulations demonstrate that field-free vortex–antivortex loops and sub-10 nm skyrmions exist in Fe/Bi_(2)O_(2)S and Fe/Bi_(2)O_(2)Se interfaces,*** results provide a possible strategy to tailor topological magnetism in ultrathin magnets/2D materials interfaces,which is extremely vital for spintronics applications.

关键词： Dzyaloshinskii–Moriya interaction field-free topological magnetism

Aggregation-induced Emission Probe for Fluorescence/Photoacoustic Dual-modality Imaging and Photodynamic/Photothermal Treatment

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Chemical research in Chinese Universities 2024年第2期40卷 293-304页

作者： CHEN Peiyu ZHANG Guoyang LI Jiguang MA Lijun ZHOU Jiaying ZHU Mingguang LI Shuo WANG Zhuo State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing100029P.R.China

The combination of near-infrared(NIR)fluorescence imaging(FLI)and photoacoustic imaging(PAI)can effectively compensate for each other’s inherent limitations,which can provide reliable and rich information on tumor ***,the development of FL/PA dual-modality imaging probes is beneficial for achieving precision cancer diagnosis and ***,we designed an efficient phototherapy agent methoxy bithiophene indene(OTIC),which was based on aggregation-induced emission(AIE)active *** improve the water dispersion and enrichment of OTIC at the tumor site,OTIC nanoparticles(OTIC NPs)were prepared by a nanoprecipitation *** balance between radiation and non-radiation energy dissipation was regulated by the strong donor-acceptor interaction and intramolecular *** OTIC NPs exhibited bright NIR fluorescence,photoacoustic signals,efficient generation of reactive oxygen species,and high photothermal conversion efficiency under NIR *** imaging of the tumor and mice sentinel lymph nodes(SLNs)with OTIC NPs was visualized by NIR FL/PA dual-modal *** the comprehensive imaging information provided by OTIC NPs in vivo,tumors were ablated under laser irradiation,which greatly improved the therapeutic *** NPs would be possible to realize the precise guidance of FL/PA imaging for tumor treatment in the future clinical application.

关键词： Aggregation-induced emission Dual-modality imaging Photodynamic/photothermal treatment