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CCS Chemistry 2024年第8期6卷 1895-1907页

作者： Jilin Fan Kuan Zhang Mingjun Xuan Xiang Gao Rostislav Vinokur Robert Göstl Lifei Zheng Andreas Herrmann DWI—Leibniz institute for Interactive Materials 52056 Aachen institute of Technical and Macromolecular Chemistry RWTH Aachen University52074 Aachen Wenzhou institute University of Chinese Academy of Sciences325001 Wenzhou

Ultrasound(US)activation of mechanophores in polymers that initiates cascade chemical reactions is a promising strategy for on-demand molecule ***,the typical US frequency used for mechanochemistry is around 20 kHz,producing inertial cavitation that exceeds the tolerance threshold of biological ***,high-intensity focused US(HIFU)as a mechanical stimulus is introduced to drive the activation of disulfide mechanophores in hyperbranched star polymers(HBSPs)and microgels(MGLs).The mechanism of molecular release is attributed to the thiol-disulfide exchange reaction and subsequent intramolecular *** reveal that HBSPs and MGLs effectively transduce HIFU as mechanical input to chemical output,demonstrated by the quantification of the release of fluorescent umbelliferone(UMB).Moreover,an in vitro study of drug release is carried out using camptothecin as the model drug,which is covalently loaded in MGLs,demonstrating the potential of our system for controlled drug delivery to cancer cells.

关键词： mechanophores polymer mechanochemistry polymeric nanostructures ultrasound drug release sonopharmacology

Recent Advances in the Synthesis and Polymerization of New CO_(2)-Based Cyclic

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Chinese Journal of Chemistry 2024年第4期42卷 430-443页

作者： Matteo Lanzi Arjan W.Kleij institute of Chemical Research of Catalonia(ICIQ) The Barcelona Institute of Science and Technology(BIST)Av.Països Catalans 1643007 TarragonaSpain Catalan institute of Research and Advanced Studies(ICREA) Pg.Lluís Companys 2308010 BarcelonaSpain

Carbon dioxide can be converted into functional heterocycles known as cyclic carbonates,whose recent reactivity has been expanded towards the formation of tailor-made engineering *** minireview gives an overview of the most topical developments in this area with a special focus on the synthetic methods employed to prepare these CO_(2)based *** addition,their application potential in the area of polymer science using a variety of polymerization techniques is discussed that have in common the ring-opening of the carbonate *** perspectives are provided that provide impetus for the scientific communities aligning research to the use of sustainable processes for polymers from recyclable carbon sources such as CO_(2).

关键词： Carbon dioxide Cyclic carbonates Functional macromolecules Heterocycles Polycarbonates Recycling Ring opening polymerization

Bibliographic survey and comprehensive review on mechanical and durability properties of microorganism based self-healing concrete

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1445-1465页

作者： Md Marghoobul HAQUE Kunal M.SHELOTE Namrata SINGH Supratic GUPTA Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi 110016India

Concrete is the most widely utilized material for construction purposes,second only to water,in the ever-increasing need for construction *** is a brittle material and possesses a high risk of crack formation and consequent ***,which allows chemicals to enter and can cause concrete structures to lose their physico-mechanical and durability *** and rehabilitating concrete structures involves high costs and leads to various repair methods including coating,adhesives,polymers,supplementary cementitious materials(SCMs),and *** of the latest technologies is the use of microorganisms in *** added microorganisms lead to calcite precipitation and thereby heal the cracks *** study presents a comprehensive literature survey on bacteria-included concrete,before which a bibliographic survey is performed using VOSViewer *** addition to regular bacterial concrete,this study focuses on also using SCMs and fibers in bacterial concrete.A detailed literature review with data representation for various mechanical properties including compressive strength(CS),split tensile strength(SS),and flexure strength(FS),along with durability properties including carbonation,water absorption,resistance against chloride ion penetration,gas permeation,and resistance against cyclic freeze-and-thaw is presented.A study on the use of X-ray computed tomography(XCT)in bacterial concrete is highlighted,and the scope for future research,along with identification of the research gap,is presented.

关键词： bacterial concrete bibliographic survey biomineralization carbonation fibers

Making topological protein links using enzymatic reactions

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National Science Review 2024年第3期11卷 50-51页

作者： Roger Castells-Graells Todd O.Yeates Department of Chemistry and Biochemistry University of California UCLA-DOE institute for Genomics and Proteomics

Proteins are exceedingly complex molecules though, at their heart, they are essentially linear polymers. Pull at their ends and one obtains an extended backbone. While that is true in most cases, some natural proteins... 详细信息

关键词： DESIGN

NIR-Ⅱ成像引导的精准光动力治疗通过干扰糖代谢重编程增强肿瘤饥饿治疗

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Science Bulletin 2024年第9期69卷 1263-1274页

作者：吴夏维凡勇王楷若缪云秋常永亮明江王欣月陆晟威刘芮池张凡张扬秦环龙施剑林 Nanomedicine and Intestinal Microecology Research Center Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsState Key Laboratory of Molecular Engineering of Polymers and iChemFudan UniversityShanghai 200433China State Key Laboratory of High Performance Ceramics and Superﬁne Microstructure Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050China

Metabolic reprogramming is a mechanism by which cancer cells alter their metabolic patterns to promote cell proliferation and growth, thereby enabling their resistance to external stress. 2-Deoxy-Dglucose(2DG) can eliminate their energy source by inhibiting glucose glycolysis, leading to cancer cell death through starvation. However, a compensatory increase in mitochondrial metabolism inhibits its efficacy. Herein, we propose a synergistic approach that combines photodynamic therapy(PDT) with starvation therapy to address this challenge. To monitor the nanodrugs and determine the optimal triggering time for precise tumor therapy, a multifunctional nano-platform comprising lanthanide-doped nanoparticle(Ln NP) cores was constructed and combined with mesoporous silicon shells loaded with2DG and photosensitizer chlorin e6(Ce6) in the mesopore channels. Under 980 nm near-infrared light excitation, the downshifted 1550 nm fluorescence signal in the second near-infrared(NIR-II, 1000–1700 nm) window from the Ln NPs was used to monitor the accumulation of nanomaterials in ***, upconverted 650 nm light excited the Ce6 to generate singlet oxygen for PDT, which damaged mitochondrial function and enhanced the efficacy of 2DG by inhibiting hexokinase 2 and lactate dehydrogenase A expressions. As a result, glucose metabolism reprogramming was inhibited and the efficiency of starvation therapy was significantly enhanced. Overall, the proposed NIR-II bioimaging-guided PDT-augmented starvation therapy, which simultaneously inhibited glycolysis and mitochondria, facilitated the effects of a cancer theranostic system.

关键词： Metabolic reprogramming Colorectal cancer Glycolytic inhibition Photodynamic therapy NIR-II imaging

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Porous organic cages as a novel platform for second harmonic generation

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Science China Chemistry 2024年第11期67卷 3669-3674页

作者： Feng Shui Yunqin Zhang Mao Yi Xiongli Liu Lin Li Shuo Zhang Yongshen Zheng Yongtao Yao Qiao Zhao Baiyan Li Xianhe Bu School of Materials Science and Engineering National Institute for Advanced Materials TKL of Metal and Molecule-Based Material Chemistry Nankai University National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology

Second harmonic generation(SHG) is one of the most extensively applied nonlinear optical phenomena. Compared to traditional inorganic SHG materials, organic SHG materials, including non-centrosymmetric small molecular crystals and organic polymers, have been extensively explored for SHG optics due to their advantageous properties, including high light-induced damage threshold, ultrafast response speed, high polarization ratio, wide transparency range, and elevated dielectric constant. However,in organic SHG materials, most small molecular crystals often show poor thermal stability(polymers have hindered their widespread application in SHG due to the requirements of processability and ***, it is significantly necessary to develop novel organic SHG material with high thermal stability, large-size crystals,excellent processability, high homogeneity, and a well SHG effect. In the contribution, we developed herein porous organic cages(POCs) as a novel platform for SHG optics. Thanks to its inherent macromolecular composition and zero-dimensional discrete structures, POCs can not only solve the instability problem of small molecule crystals but also overcome the drawbacks in growing large-size crystals for organic polymer. The obtained two POCs with chiral asymmetric centers(CPOC-R-5 and CPOCS-7) display advantageous features for SHG optics including well SHG performance, large-size crystal(5 mm×3 mm×1 mm),high thermal stability(≥250 °C), wide transparency window(750–2,000 nm) and high polarization ratio(up to 94.5%). This work thus develops POCs as a new platform toward the construction of organic NLO materials with the potential application in sorts of SHG optics.

关键词： porous organic cages second harmonic generation novel SHG platform high thermal stability large-size single crystal

Application of interpolated double network model for carbon nanotube composites in electrothermal shape memory behaviors

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Acta Mechanica Sinica 2024年第8期40卷 133-153页

作者： Ting Fu Zhao Yan Li Zhang Ran Tao Yiqi Mao Department of Engineering Mechanics College of Mechanical and Vehicle EngineeringHunan UniversityChangsha410082China State Key Laboratory of Explosion Science and Technology Institute of Advanced Structure TechnologyBeijing Institute of TechnologyBeijing100081China

Multi-wall carbon nanotube filled shape memory polymer composite(MWCNT/SMC)possessed enhanced modulus,strength,and electric conductivity,as well as excellent electrothermal shape memory properties,showing wide design scenarios and engineering application *** thermoelectrically triggered shape memory process contains complex multi-physical mechanisms,especially when coupled with finite deformation rooted on micro-mechanisms.A multi-physical finite deformation model is necessary to get a deep understanding on the coupled electro-thermomechanical properties of electrothermal shape memory composites(ESMCs),beneficial to its design and wide *** into consideration of micro-physical mechanisms of the MWCNTs interacting with double-chain networks,a finite deformation theoretical model is developed in this work based on two superimposed network chains of physically crosslinked network formed among MWCNTs and the chemically crosslinked *** intact crosslinked chemical network is considered featuring with entropic-hyperelastic properties,superimposed with a physically crosslinked network where percolation theory is based on electric conductivity and electric-heating *** model is calibrated by experiments and used for shape recoveries triggered by heating and electric *** captures the coupled electro-thermomechanical behavior of ESMCs and provides design guidelines for MWCNTs filled shape memory polymers.

关键词： Shape memory polymer composite Viscoplastic constitutive relations Electro-thermomechanics Double network model Multiple shape memory

From oxygenated monomers to well-defined low-carbon polymers

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Chinese Chemical Letters 2024年第1期35卷 40-44页

作者： Yanni Xia Chengjian Zhang Yong Wang Shunjie Liu Xinghong Zhang National Key Laboratory of Biobased Transportation Fuel Technology International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Polymer Ecomaterial Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shanxi-Zheda institute of Advanced Materials and Chemical Engineering Hangzhou 310027China

The synthesis of degradable polymers with easy-to-break in-chain carbon-oxygen bonds has attracted much *** minireview introduces the synthesis of a variety of degradable polymers from the(co)polymerizations of several typical oxygenated monomers such as epoxides,cyclic carbonates,cyclic esters,carbon dioxide(CO_(2)),carbonyl sulfide(COS),and cyclic *** highlight the catalysts and mechanisms for these(co)*** ring-opening copolymerization of five-membered carbonate with cyclic anhydride or COS has been *** also highlight the synthesis of block copolymers and cyclic copolymers with well-defined sequences by the method of growing center *** hope that these new polymerization systems can provide new ideas for the development of degradable low-carbon polymers in the future.

关键词： Polymer synthesis Degradable polymer Low-carbon polymer Catalysis Ring-opening polymerization

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Structural engineering of antimicrobials for optimal broad-spectrum activity

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Green Chemical Engineering 2024年第4期5卷 473-482页

作者： Arunmozhiarasi Armugam Diane S.W.Lim Siti Nurhanna Riduan Shook Pui Chan Jerome Asugan Yugen Zhang institute of Bioengineering and Bioimaging institute of Sustainability for Chemicals Energy and Environment(ISCE2) Agency for Science Technology and Research (A*STAR) Diploma in Biomedical Science School of Chemical and Life SciencesSingapore Polytechnic

Antimicrobial materials are a crucial component in eradicating and managing the spread of infectious *** are expected to act on a broad-spectrum of microbes, including emerging pathogens which could cause the next Disease X. Herein, we reassessed a series of antimicrobial imidazolium polymers on our shelves and uncovered extended functionality through dual modes of action. By redesigning their structures, a truly broadspectrum antimicrobial material with optimized activity against bacteria(G +ve, G-ve) and fungi, as well as enveloped and non-enveloped viruses was developed. We demonstrated that the imidazolium polymer exhibits dual modes of function against microbes: targeting the microbial membrane and binding DNA. The latter DNA binding affinity was found to be key against non-enveloped viruses. With this insight, we designed small molecule compounds that exhibited optimum broad-spectrum antimicrobial activity and excellent efficacy against ESKAPE group of pathogens that are responsible for some of the deadliest nosocomial infections worldwide. Our results could also shed light on the design of broad-spectrum antimicrobial compounds against Disease X.

关键词： Broad-spectrum Antimicrobial Polyimidazolium Structure-function Membrane active

Efficient Electromagnetic Wave Absorption and Thermal Infrared Stealth in PVTMS@MWCNT Nano‑Aerogel via Abundant Nano‑Sized Cavities and Attenuation Interfaces

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Nano-Micro Letters 2024年第1期16卷 370-383页

作者： Haoyu Ma Maryam Fashandi Zeineb Ben Rejeb Xin Ming Yingjun Liu Pengjian Gong Guangxian Li Chul B.Park College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University24 Yihuan RoadNanyiduanChengdu 610065SichuanPeople’s Republic of China Microcellular Plastics Manufacturing Laboratory Department of Mechanical and Industrial EngineeringUniversity of Toronto5 King’s College RoadTorontoON M5S 3G8Canada Jiangsu JITRI Advanced Polymer Materials Research institute Tengfei Building88 Jiangmiao RoadJiangbei New DistrictNanjing 211800JiangsuPeople’s Republic of China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringInternational Research Center for X PolymersZhejiang University38 Zheda RoadHangzhou 310027People’s Republic of China

Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)*** fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work.

关键词： Nano-pore size Heterogeneous interface Electromagnetic wave absorption Thermal infrared stealth Nano-aerogel

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