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Versatile Recyclable Kevlar Nanofibrous Aerogels Enabled by Destabilizing Dynamic Balance Strategy

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Advanced Fiber Materials 2023年第3期5卷 1050-1062页

作者： Lishan Li Jing Lyu qingqing cheng Chen Fu Xuetong Zhang Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesSuzhou 215123People’s Republic of China Division of Surgery and Interventional Science University College LondonLondon NW32PFUK

Aerogels are of great interest in diverse fields including thermal insulation,environmental protection,liquid separation,electromagnetic shielding,***,the development of renewable and recyclable aerogels,especially synthetic pol-ymer-based ones,remains an enormous challenge,which seriously hinders the practical application of ***,utilizing Kevlar nanofibers(KNFs)as representative synthetic polymer building blocks,a destabilizing dynamic balance(DDB)strategy is proposed to fabricate recyclable aerogels with high reprocessing *** specifically,aprotic esters(e.g.,di-tert-butyl decarbonate,DiBoc)and alkalis(e.g.,potassium tert-butoxide,t-BuOK)are introduced to trigger the destabilizing dynamic balance between deprotonation–protonation of KNFs,resulting in a reversible sol–gel ***,the duration of sol–gel transition(i.e.,gelation)time,adjustable from 10^(–2)to 10^(3)min,is compatible with versatile processing methods,such as static mould casting,dynamic wet spinning,dynamic blade coating and dynamic 3D *** unique advantages enable the fabrication of various KNF aerogel products(i.e.,continuous fibers,continuous films,large-sized monoliths and 3D-printed articles)with low density(33–165 mg/cm3),high compressive modulus(up to 52 MPa),high specific surface area(360–404 m^(2)/g)and low thermal conductivity(0.027–0.050 W/m·K).Notably,these properties are comparable or superior to that of previously reported KNF aerogels and far superior to that of recyclable *** with direct fabrication from raw materials,the DDB strategy reduces the cost by 50.5%and 82.5%when products are made from recycled aerogels and wet gels,*** cost reduction further increases with the number of recycling cycles,which is calculated as$275 per kilogram KNF aerogel with 5 *** work develops extraordinary KNF aerogels those can be recycled and reused,as well as provides a strategy that can be applied to design mor

关键词： Aerogel Kevlar Recyclability Versatile processing Dynamic balance

Chiral AuCu heterostructures with site-specific geometric control and tailored plasmonic chirality

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Science China Chemistry 2023年第11期66卷 3280-3289页

作者： Guizeng Yang Lichao Sun Yunlong Tao qingqing cheng Xuehao Sun Chuang Liu Qingfeng Zhang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China

Rational design and construction of chiral-achiral hybrid structures are of great importance to realize the multifunctional complex chiral structures toward emerging technological applications. However, significant challenges remain due to the lack of fine control over the heterostructure. Here, we have developed a general bottom-up synthetic strategy for the site-selective growth of Cu nanodomains on intrinsically chiral Au nanocrystals. Chiral AuCu heterostructures with three distinct architectures were achieved by controlling the overgrowth of Cu nanodomains in a site-specific manner. The geometry-dependent plasmonic chirality of the heterostructures was demonstrated experimentally by circular dichroism spectroscopy and theoretically through finite-difference time-domain simulations. The site-specific geometric control of chiral AuCu heterostructures was also extended to employ anisotropic chiral Au nanoplates and nanorods as the building blocks. By virtue of the galvanic replacement reactions between metal ions and Cu atoms, chiral heterostructures with increasing architectural complexity and compositional diversity can be further achieved. The current work not only opens up a promising strategy to synthesize complex chiral hybrid nanostructures but also provides an important knowledge framework that guides the rational design of multifunctional chiral hybrid nanostructures toward chiroptical applications.

关键词： chiral nanomaterials AuCu heterostructures site-selective growth plasmonic chirality galvanic replacement reaction

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Implementation and Insights on Science Inquiry Activities in Kindergartens Under the Concept of STEM Education

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Journal of Contemporary Educational Research 2024年第7期8卷 182-186页

作者： qingqing cheng The Fourth Kindergarten of Xi’an Aerospace City Xi’an 710100Shaanxi ProvinceChina

The STEM education philosophy spans across disciplines such as science,technology,engineering,and *** the context of thematic activities in kindergartens,teachers can utilize the STEM education philosophy to cultivate children’s innovative thinking qualities and practical operation skills,helping them develop a scientific inquiry spirit and *** paper takes the development of science inquiry activities in kindergartens as a path,exploring the significance and implementation paths of applying the STEM education philosophy in such activities.

关键词： STEM education Science inquiry Thematic activities

Broadband achromatic metalens in terahertz regime

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Science Bulletin 2019年第20期64卷 1525-1531页

作者： qingqing cheng Meilin Ma Dong Yu Zhixiong Shen Jingya Xie Juncheng Wang Nianxi Xu Hanming Guo Wei Hu Shuming Wang Tao Li Songlin Zhuang Shanghai Key Lab of Modern Optical System and Engineering Research Center of Optical Instrument and System(Ministry of Education) University of Shanghai for Scienceand TechnologyShanghai200093China National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesSchool of PhysicsNanjing UniversityNanjing210093China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun130033China

Achromatic focusing is essential for broadband operation, which has recently been realised from visible to infrared wavelengths using a metasurface. Similarly, multi-terahertz functional devices can be encoded in a desired metasurface phase profile. However, metalenses suffer from larger chromatic aberrations because of the intrinsic dispersion of each unit element. Here, we propose an achromatic metalens with C-shaped unit elements working from 0.3 to 0.8 THz with a bandwidth of approximately 91% over the centre frequency. The designed metalens possesses a high working efficiency of more than 68% at the peak and a relatively high numerical aperture of 0.385. We further demonstrate the robustness of our Cshaped metalens, considering lateral shape deformations and deviations in the etching depth. Our metalens design opens an avenue for future applications of terahertz meta-devices in spectroscopy, time-offlight tomography and hyperspectral imaging systems.

关键词： Far infrared or terahertz Achromatic Metasurface Diffraction theory

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A New Hesitant Fuzzy Multiple Attribute Decision Making Method with Unknown Weight Information

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Advances in Pure Mathematics 2020年第7期10卷 405-431页

作者： Shenqing Jiang Wei He qingqing cheng Institute of Mathematics Nanjing Normal University Nanjing China Department of Basic Courses Jiangsu Shipping College Nantong China Department of Theory Party School of Haimen City Committee (Haimen Administration Institute) Haimen China

In this paper, we focus on a new approach based on new generalized hesitant fuzzy hybrid weighted aggregation operators, in which the evaluation information provided by decision makers is expressed in hesitant fuzzy elements (HFEs) and the information about attribute weights and aggregation-associated vector is unknown. More explicitly, some new generalized hesitant fuzzy hybrid weighted aggregation operators are proposed, such as the new generalized hesitant fuzzy hybrid weighted averaging (NGHFHWA) operator and the new generalized hesitant fuzzy hybrid weighted geometric (NGHFHWG) operator. Some desirable properties and the relationships between them are discussed. Then, a new algorithm for hesitant fuzzy multi-attribute decision making (HF-MADM) problems with unknown weight information is introduced. Further, a practical example is used to illustrate the detailed implementation process of the proposed approach. A sensitivity analysis of the decision results is analyzed with different parameters. Finally, comparative studies are given to verify the advantages of our method.

关键词： MADM Hesitant Fuzzy Set (HFS) New Generalized Hesitant Fuzzy Hybrid Weighted Aggregation Operators

Boosting hydrogen peroxide production via establishment and reconstruction of single-metal sites in covalent organic frameworks

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SusMat 2023年第3期3卷 379-389页

作者： Shuai Yang Lanlu Lu Ji Li qingqing cheng Bingbao Mei Xuewen Li Jianing Mao Panzhe Qiao Fanfei Sun Jingyuan Ma Qing Xu Zheng Jiang Shanghai Advanced Research Institute Chinese Academy of SciencesShanghaiChina School of Physical Science and Technology ShanghaiTech UniversityShanghaiChina Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghaiChina University of Chinese Academy of Sciences BeijingChina CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of ScienceShanghaiChina National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefeiChina

Covalent organic frameworks(COFs)have been well developed in electrocatalytic systems owing to their controllable skeletons,porosities,and ***,the catalytic process in COFs remains underexplored,hindering an in-depth understanding of the catalytic *** this work,uniform Pt-N_(1)O_(1)Cl_(4)sites chelated via C-N and C=O bonds along the one-dimensional and open channels of TP-TTA-COF were *** from conventional single-metal sites constructed for the near-free platinum for hydrogen evolution,the as-constructed PtCl-COF showed 2e−oxygen reduction for H_(2)O_(2)*** tracked the dynamic evolution process of atomic Pt sites in which Pt-N_(1)O_(1)Cl_(4)was transformed into Pt-N_(1)O_(1)(OH)_(2)using in situ X-ray *** theoretical calculations revealed that the strong Pt-support interaction in Pt-N_(1)O_(1)(OH)_(2)facilitated*OOH formation and thus led to higher selectivity and activity for the oxygen reduction reaction in the 2e−*** work can expand the applications of COFs through the regulation of their local electronic states for the manipulation of the metal center.

关键词： covalent organic framework oxygen reduction reaction single-atom catalysis

A mild, configurable, flexible CoNi-LDH（v）/Zn battery based on H-vacancy-induced reversible Zn2+ intercalation

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Journal of Energy Chemistry 2025年第1期100卷 498-508页

作者： Xinyue cheng Dingsheng Wu Hao Gao qingqing Wang Pengfei Lv Sam S.Yoon Qufu Wei Key Laboratory of Eco-textiles Ministry of Education Jiangnan University School of Mechanical Engineering Korea University

Flexible Zn-based batteries have attracted increasing research interest as essential components of wearable energy storage ***,the advancement of flexible aqueous Zn-based batteries based on Co-Ni layered double hydroxide （CoNi-LDH） as the cathode material is hampered by their poor cycling stability and the corrosiveness of alkaline ***,CoNi-LDH nanosheets enriched with H vacancies (CoNi-LDH（v）) were constructed on a flexible carbon cloth （CC） substrate via electrochemical deposition and *** Zn-based battery comprising CoNi-LDH（v）@CC as the cathode exhibited highly reversible conversion reactions and stable operation in 3 M ZnSO4electrolyte （pH=4）.The battery delivered an excellent specific capacity (225 mA h g-1,0.26 mA h cm-2),acceptable cycling stability（53.9%,900 cycles）,and high discharging *** abundant H vacancies served as active sites for the reversible intercalation of Zn2+and the extravasation of NO3-generated channels and space for Zn2+transport and storage,together enabling an excellent Zn2+storage ***,a sandwich-structured solid-state CoNi-LDH（v）@CC//Zn@CC battery was fabricated and was found to exhibit a noteworthy electrochemical performance and mechanical *** a proof of concept,the unencapsulated battery powered a digital watch under various deformation conditions and operated stably for 80 ***,the flexible battery displayed outstanding customizability,maintaining an open-circuit voltage of 1.42 V even after being cut *** proposed engineering strategy contributes to the realization of textiles with truly wearable energy-storage devices.

关键词： CoNi/Zn battery H vacancies Mild aqueous electrolyte Tailorable battery Wearable energy storage device

Unraveling the complex interactions between plasmonic Ag nanoparticles and biomolecules for enhancing molecular chirality

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Science China Chemistry 2024年

作者： Chen Wang Yunlong Tao qingqing cheng Dandan Lu Chuang Liu Guizeng Yang Xuehao Sun Lichao Sun Qingfeng Zhang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University Suzhou Institute of Wuhan University

Plasmonic nanostructures have been widely employed to enhance the chiral light-matter interactions for chirality sensing owing to their intriguing optical properties. However, a quantitative understanding of the correlation between enhanced molecular chirality and plasmonic properties in plasmonic nanoparticle-molecule complexes remains a challenge yet to be addressed. Here we demonstrate the complex interactions between Ag nanoparticles and biomolecules that generate distinct plasmonic circular dichroism signals ranging from UV to visible wavelengths. By deliberately changing the surface coverage of chiral molecules,the geometry of Ag nanoparticles, and the aggregation states of the complexes, three distinct underlying mechanisms were found to be intertwined and hybridized for enhancing circular dichroism signals. We further employed the chiral plasmonic nanoparticle-molecule complexes to quantify the enantiomeric purity of cysteine and explore their possible applications in other chiral molecules. The insights gained from this work shed light on the underlying mechanisms dictating the enhanced circular dichroism signals of chiral plasmonic nanoparticle-molecule complexes.

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产业强市的绩效测度与空间关联——基于长三角主要城市的实证

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华东经济管理 2023年第10期37卷 23-32页

作者：成青青中共南通市委党校党的建设理论与实践创新研究中心江苏南通226007 中共南通市海门区委党校咨政研究科江苏南通226100

文章运用产业结构偏离度、工业相对比重、区域创新活动模型、区位商和城市流强度等测算方法,在构建产业强市评价指标体系基础上,对长三角主要城市的产业结构、产业优势、产业创新、产业联系和产业环境进行绩效测度和空间关联分析。结果... 详细信息

文章运用产业结构偏离度、工业相对比重、区域创新活动模型、区位商和城市流强度等测算方法,在构建产业强市评价指标体系基础上,对长三角主要城市的产业结构、产业优势、产业创新、产业联系和产业环境进行绩效测度和空间关联分析。结果表明:就业结构与产业结构越接近,产业结构效益越好;产业创新值越高,创新优势越明显;区位商和城市流强度越大,产业联系与优势、产业辐射与带动越明显。因此,推进产业强市,必须加快新旧动能转换,聚焦全产业链发展,不断推进产业聚变、技术质变、应用裂变,提升城市综合实力。

关键词：产业强市绩效测度空间关联城市流强度