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Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy

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Chinese Journal of Polymer Science 2024年第10期42卷 1525-1535,I0012页

作者： Zhen-Yu Wang Xiao-Kong Liu State Key laboratory of Supramolecular structure and Materials College of ChemistryJilin UniversityChangchun130012China

Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace,defense,and opto-electronics,but polyimides are difficult to be reprocessed and recycled at the end of their service life,resulting in a significant waste of ***,it is of great significance to develop recyclable polyimides with comparable properties to the commercial ***,we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII)plastic,synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine *** PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial *** PtM-CR-PII plastic possesses a high young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa,which also exhibits high thermal stability with a glass transition temperature of≈220℃.Moreover,the PtM-CR-PII plastic exhibits outstanding waterproofness,acid/alkali-resistance,and solvent-resistance,its appearance and mechanical properties can be well maintained after long-term soaking in water,highly concentrated acid and base,and various organic ***,the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame *** PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index(LOI)value of 45.5%.Importantly,the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature,allowing easy separation and recovery of both monomers in high *** recovered pure monomers can be used to regenerate new PtM-CR-PII plastics,enabling sustainable polymer-monomers-polymer circulation.

关键词： Chemical recyclability Polyimides Polyimines Dynamic imine bonds Mechanical properties Chemical stability

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From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

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Progress in Natural Science:Materials International 2024年第01期34卷 66-73页

作者： Miao Chang Chiyao Tang Chong-Chen Wang Chen Zhao Beijing Key laboratory of Functional Materials for Building structure and Environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment

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Electrodeposition of rare refractory metals in low-temperature ionic liquids

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Rare Metals 2024年第10期43卷 4921-4933页

作者： Lin-Lin Wang Han-Dong Jiao Rui Yuan Le-Yang Li Man-Peng Lin Rui-Yang Sun Jiu-San Xiao Shu-Qiang Jiao Institute of Advanced structure Technology Beijing Institute of Technology State Key laboratory of Advanced Metallurgy University of Science and Technology Beijing

Rare refractory metals(RRMs) play a significant role in fundamental industries, including electronics,chemical industry, machinery, etc., and future advanced fields, such as aerospace and superconductivity. However,the traditional production processes of RRMs based on high-temperature thermal reduction cannot meet the requirements of low-energy consumption. This dilemma could be addressed efficiently by using a low-temperature electrodeposition strategy in ionic liquids(ILs). This review summarizes a panoramic view of the latest developments on the electrodeposition of RRMs in ILs after a brief review on the current industrial production methods of RRMs. Based on this, the electrochemical mechanism occurring at the cathode during the electrodeposition process of RRMs in different electrolytes and under different conditions is thoroughly discussed, because it is crucial for the successful production of pure RRMs. In addition, this review not only analyses the main challenges that hinder the industrial application of the electrodeposition of RRMs in ILs, but also proposes corresponding solutions. We hope this review can provide a valuable guidance for the fundamental research and industrial development of lowtemperature electrodeposition of RRMs.

关键词： Chemical industry

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Supramolecular polymer network constructed by a functionalized polyimidazolium salt derived from metal-carbene template approach

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Science China Chemistry 2024年第4期67卷 1224-1228页

作者： Ming-Ming Gan Zi-En Zhang Yi-Fan Zhang Heng Zhang Li-Ying Sun Ying-Feng Han Key laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

In this study,we present a supramolecular templating approach for constructing polyimidazolium salt containing crown ether and cyclobutane *** strategy involves the formation of metal-carbene templates,photochemical cycloaddition,and subsequent demetallation of metal *** by the host-guest chemistry between crown ether units and ammonium salts,we successfully fabricated a supramolecular polymer SPN1,which features imidazolium receptors and cyclobutane *** obtained SPN1 demonstrates outstanding reversible stimulus-response,antibacterial behavior and conductivity.

关键词： metal-carbene template crown ether polyimidazolium salt host-guest chemistry

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A near-infrared fluorescent probe for visualizing transformation pathway of Cys/Hcy and H2S and its applications in living system

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Chinese Chemical Letters 2024年第5期35卷 296-301页

作者： Yudi Cheng Xiao Wang Jiao Chen Zihan Zhang Jiadong Ou Mengyao She Fulin Chen Jianli Li Key laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127China Key laboratory of Resource biology and Biotechnology in Western China Ministry of EducationBiomedicine Key Laboratory of Shaanxi ProvinceLab of Tissue Engineeringthe College of Life SciencesFaculty of Life Science&MedicineNorthwest UniversityXi’an 710069China

Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various ***,we developed a near-infrared intramolecular charge transfer(ICT)based fluorescent probe Y-NBD,achieving detection of Cys/Hcy and H_(2)S with different fluorescent signals(green-red for Cys/Hcy,red for H_(2)S),large Stokes shifts(∼100/105nm or 191 nm)and high signal-background-ratio,but not responding to GSH.Y-NBD was successfully applied to image exogenous/endogenous Cys/Hcy and H_(2)S in various living cancer cells(HeLa,A549,and HepG2)and in *** not only visualized the transformation pathway of several thiols in HepG2 cells but also verified that the intestine is the main site for the activation and metabolism of Y-NBD in zebrafish,as well as realized to evaluate the degree of drug-induced liver *** work provides a promising tool for imaging Cys/Hcy and H_(2)S in living systems and shows great potency in evaluating drug-induced liver injury and its treatment.

关键词： Fluorescent probe Near-infrared Hydrogen sulfide Cysteine/homocysteine Large Stokes shift Dicyanoisophorone Drug-induced liver injury

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Recent progress in MOFs-based nanozymes for biosensing

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Nano Research 2024年第1期17卷 39-64页

作者： Imamdin Chandio Yongjian Ai Lei Wu Qionglin Liang MOE Key laboratory of Bioorganic Phosphorus Chemistry&Chemical biology Department of ChemistryLaboratory of Flexible Electronics TechnologyCenter for Synthetic and Systems BiologyTsinghua University-Peking University Joint Centre for Life SciencesTsinghua UniversityBeijing 100084China

Nanozymes are nanomaterials with enzyme-mimicking catalytic *** to natural enzymes,nanozymes show various properties such as easy to manufacture,stable,adjustable,and *** play key roles in biosensing,biocatalysis,and disease *** an important kind of nanozymes,metal-organic framework(MOF)-based nanozymes are receiving a lot of attention due to their structural properties and *** developing MOF with enzymes-like catalytic properties has opened new perspectives in *** review summarizes the up-to-date developments in synthesizing two-dimensional and three-dimensional MOF-based nanozymes and their applications in ***,classification of nanozymes obtained by MOFs is categorized,and different properties of MOF-based nanozymes are ***,the distinctive applications of MOF-based nanozymes in identifying various analytes are thoroughly ***,the recent challenges and progressive directions in this area are highlighted.

关键词： metal-organic frameworks nanozymes metal-organic framework (MOF)-based nanozymes biosensing analytes

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Molecule configurations modulate packing array and charge transfer in cocrystal engineering

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Science China Chemistry 2024年第2期67卷 512-516页

作者： Shenglong An Mengyuan Qiao Xin Jin Xuanying Chen Jianhua Su Lifang Guo Zhiyun Zhang Key laboratory for Advanced Materials and Joint International Research laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CentreFrontiers Science Center for Materiobiology and Dynamic ChemistryEast China University of Science&TechnologyShanghai200237China

Organic cocrystal as an emerging assembly strategy has received increasing attention in constructing multiple functional materials,through continually screening suitable constituent monomers or changing their stoichiometry ***,the role of molecule configuration in the cocrystal field is rarely explored despite the fascinating potential in regulating the packing *** this study,the N,N′-diphenyl-5,10-dihydrophenazine derivatives(DPPs) with the flexible scaffold and different methyl substitutions are selected as the donors bearing various molecular *** a simple collaborative way,a series of cocrystals based on DPPs and OFN(octafluoronaphthalene) are fabricated,exhibiting two self-adaptive molecular stacking arrays.X-ray crystallographic analysis and theoretical calculation unveil their different π···π interactions and charge transfer characters,leading to the significant emission redshift up to 125 nm compared with individual *** a result,controllable molecule stacking structure,tunable emission,and charge transfer properties can be *** study provides a new perspective to reveal the structure-property relationships at the molecular level by controlling the molecule configuration in cocrystal engineering,contributing to the development of cocrystal theoretical physics and organic functional materials.

关键词： cocrystals molecular configuration self-adaptive packing mode charge transfer

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NHC-derived carbon-centered luminescent radicals with shortwavelength emission via suppression of Kasha's rule

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Science China Chemistry 2024年第8期67卷 2679-2685页

作者： Can Chen Xin Li Xinhua Ouyang Ying-Feng Han Key laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China College of Material Engineering Fujian Agriculture and Forestry University Fuzhou 350108China

Luminescent organic radicals have garnered increasing attention owing to their versatile applications in sensing, imaging, and organic light-emitting diodes(OLEDs), attributed to their unique emission properties originating from the doublet spin ***, the natural narrow bandgap of organic free radicals typically limits their emission to the long-wavelength *** luminescent organic radicals with short-wavelength emission remains a significant challenge. Herein, a series of carbon-centered radicals with short-wavelength emission(383–476 nm) by combining N-heterocyclic carbenes with various polycyclic aromatic hydrocarbons(PAHs)(2-naphthyl, 2a~Ⅰ and 2b~Ⅰ;2-phenanthryl, 2a~Ⅱand 2b~Ⅱ;2-anthryl, 2a~Ⅲand 2b~Ⅲ;3-phenanthryl, 2a~Ⅳand 2b~Ⅳ). Theoretical calculations reveal that the introduction of PAHs significantly increases the ΔE_(D2-D1) in 2a^(Ⅰ–Ⅲ)and 2b^(Ⅰ–Ⅲ)compared to that in phenyl-derived radical congeners. Consequently, the internal transition from D2 to D1 is impeded, leading to a high yield of D2 emission and a suppressed Kasha's rule, thereby overcoming the limitations imposed by their narrow bandgap. For 2a~Ⅳ and 2b~Ⅳ, despite a moderately large ΔED2-D1value, the ΔED3-D1value exceeds 1 e V, indicating that their emission likely originates from the D3 state. Furthermore, we utilized 2a~Ⅲand 2b~Ⅲ as emissive materials in OLEDs,resulting in blue emissions with external quantum efficiencies of 7.5% and 6.5%, respectively.

关键词： N-heterocyclic carbenes luminescent organic molecules carbon-centered radicals short-wavelength emission

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Geographical patterns and determinants of insect biodiversity in China

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Science China(Life Sciences) 2024年第6期67卷 1255-1265页

作者： Huizhong Fan Tongyi Liu Youhua Chen Ziyan Liao Jun Chen Yibo Hu Gexia Qiao Fuwen Wei CAS Key laboratory of Animal Ecology and Conservation biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key laboratory of Mountain Ecological Restoration and Bioresource Utilization&China-Croatia“Belt and Road”Joint laboratory on Biodiversity and Ecosystem Services Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Jiangxi Provincial Key laboratory of Conservation biology College of ForestryJiangxi Agricultural UniversityNanchang 330045China University of Chinese Academy of Sciences Beijing 100049China

Insects play important roles in the maintenance of ecosystem functioning and the provision of livelihoods for millions of ***,compared with terrestrial vertebrates and angiosperms,such as the giant panda,crested ibis,and the metasequoia,insect conservation has not attracted enough attention,and a basic understanding of the geographical biodiversity patterns for major components of insects in China is ***,we investigated the geographical distribution of insect biodiversity across multiple dimensions(taxonomic,genetic,and phylogenetic diversity)based on the spatial distribution and molecular DNA sequencing data of *** analysis included 18 orders,360 families,5,275 genera,and 14,115 species of *** results revealed that Southwestern and Southeastern China harbored higher insect biodiversity and numerous older lineages,representing a museum,whereas regions located in Northwestern China harbored lower insect biodiversity and younger lineages,serving as an evolutionary *** also observed that mean annual temperature and precipitation had significantly positive effects,whereas altitude had significantly negative effects on insect biodiversity in most ***,cultivated vegetation harbored the highest insect taxonomic and phylogenetic diversity,and needleleaf and broadleaf mixed forests harbored the highest insect genetic *** results indicated that human activities may positively contribute to insect spatial diversity on a regional *** study fills a knowledge gap in insect spatial diversity in *** findings could help guide national-level conservation plans and the post-2020 biodiversity conservation framework.

关键词： insect spatial patterns multiple dimensions driving factors vegetation types

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Experimental determination of the young’s modulus of individual single-walled carbon nanotubes with single chirality

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Nano Research 2024年第8期17卷 7522-7532页

作者： Jianlin Sun Xiao Zhang Yanchun Wang Mingming Li Xiaojun Wei Huaping Liu Weiya Zhou Beijing National laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences and College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials laboratory Dongguan 523808China Beijing Key laboratory for Advanced Functional Materials and structure Research Beijing 100190China

One-dimensional carbon nanotube(CNT)exhibits excellent mechanical properties and is considered to be an ideal candidate material for the space ***,subtle changes in its chirality strongly affect its physical and chemical properties,including mechanical properties(such as young's modulus,YM).Theoretical studies reveal that the YMs of perfect single-walled carbon nanotubes(SWCNTs)are in the order of TPa and related to their ***,due to the lack of SWCNTs samples with well-defined structures and the difficulties in mechanical tests on individual SWCNTs,the theoretical correlations between YM and structure of SWCNTs have not been verified and are still in debate,which directly influences the practical utilization of the excellent mechanical properties of *** this work,we have developed an experimental method to measure the YM of an individual micrometer-scale suspended CNT by atomic force microscopy.A distinct regularity is found between the YM and chirality(i.e.,chiral angle and diameter)of SWCNT in the experiment for the first *** comparing the YMs of SWCNTs with similar diameters and different chiral angles,it manifests that the SWCNT with a near zigzag configuration has a larger *** finding suggests that the effect of SWCNT’s structures on the YMs cannot be *** developed method of measuring YMs of SWCNTs will be valuable for further experimental research on the inherent physical and chemical properties of SWCNTs.

关键词： young's modulus single-walled carbon nanotubes single chirality atomic force microscopy

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