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Self-Assembly Ultrathin Films Based On Dendrimers WANG Jin-Feng, JIA Xin-Ru, LI Ying, ZHONG Hong, CHEN Jin-Yu, LUO Guo-Bin, LI Ming-Qian, WEI Yen Chem. J. Chinese Universities    2001, 22 (10): 1773-1775.   Abstract （1598）      PDF（pc） （1079KB）（7297）       Knowledge map    Save An ultrathin film with forth generation poly(aminoamine)(PAMAM) dendrimers (methyl quaternary ammonium salt) as polycation and poly(sodium p styrenesulfonate) (PSS) as polyainon was fabricated via sequential deposition. It shows that the step by step depositions carried out smoothly by monitoring with UV Vis spectrometer. The multilayer film is rather flat with a mean roughness of 0.39 nm determined by AFM. The average thickness of a bilayer is 5.0 nm obtained from XRD, which indicates that the dendrimers molecules were compressed and possess high flattening. Related Articles | Metrics

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CuBi2O4/Bi2WO6 Z-type Heterostructures for Effective Removal Ciprofloxacin in Photo-electro-Fenton-like System WANG Qiuxia, HAN Yugui, ZHAO Peng, WANG Shuang, LIU Yaru, LI Yi Chem. J. Chinese Universities    2024, 45 (1): 20230370-.   DOI: 10.7503/cjcu20230370 Abstract （767）   HTML （30）    PDF（pc） （7287KB）（4981）       Knowledge map    Save In response to the serious problem of antibiotic pollution in the current water environment， herein， a CuBi2O4/Bi2WO6（CBWO） Z-type heterojunction photoelectric catalyst was synthesized by a simple solvothermal method. The morphology and structure were obtained through SEM， which showed that the structure of the CBWO-60 was cuboid rod-like morphology and nanosheet. The EDS elemental mapping images displayed that Cu， W， Bi and O elements were evenly dispersed in CBWO-60. The crystalline phases and molecular structures of the catalyst were determined by XRD and FTIR. These results firmly confirmed that the successful synthesis of the composite. The large specific surface area of CBWO-60 was investigated via BET. XPS analysis proved that the Cu+ and Cu2+ coexisted， which promoted the cycling of Fenton reaction. Moreover， the displacement of binding energy well verified the strong electronic interaction rather than a physical contact between CuBi2O4 and Bi2WO6 in the heterojunction. The band structure of the heterojunction was proved by UV-Vis DRS and VB-XPS analysis. The interface charge transfer situation of the heterojunction was investigated by PL， EIS， and transient photocurrent response spectra. In a series of catalysts， CBWO-60 has the highest degradation efficiency for Ciprofloxacin（CIP） in the photo-electro- Fenton-like（PEF-like） system， with a degradation efficiency of 98.0% at 90 min. At the same time， when the initial pH of the solution was in the range of 2—6， the system could always maintain effective CIP removal efficiency. The pH range of this system was broadened to some extent compared to the conventional Fenton method. In the PEF-like system， CBWO-60 showed high catalytic activity to quinolone， sulfonamides and tetracycline antibiotics， which proved the universality of CBWO-60. Finally， the degradation efficiency of CIP still maintained 87.8% after five cycles of experiments， and the crystal structure of CBWO-60 remained unchanged after the reaction. Based on the results of HPLC-MS， five possible pathways for CIP degradation were proposed. This study provided a new idea for the purification and treatment of antibiotic pollution in the water environment. Table and Figures | Reference | Related Articles | Metrics

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Rapid Grafting of Phenylboronic Acid with Hydroxypropyl Chitosan Mediated by HATU LI Aoqi, HU Chuanzhi, SHI Han, DENG Mingyu, XIAO Bo, JIANG Bo Chem. J. Chinese Universities    2023, 44 (6): 20220698-.   DOI: 10.7503/cjcu20220698 Abstract （1215）   HTML （48）    PDF（pc） （1100KB）（5195）       Knowledge map    Save Phenylboronic acid（PBA） can form reversible covalent bonds with cis-1，2-diol or 1，3-diol in an aqueous solution， which makes it useful as the glucose-responsive units or dynamic cross-linking groups in nano/hydrogels. In this paper， PBA was efficiently grafted on hydroxypropyl chitosan（HPCS） by employing 2-（7-azabenzotriazol-1-yl）- N，N，N'，N'-tetramethyluronium hexafluorophosphate（HATU） as a coupling reagent in dimethyl sulfoxide（DMSO）. The resulting carboxyphenylboronic acid-grafted hydroxypropyl chitosan（CPBA-HPCS） was soluble when pH>8.5， and the structure was characterized and confirmed by Fourier-transform infrared spectroscopy（FTIR） and nuclear magnetic resonance（NMR）. In addition， the kinetics of the reaction were studied and a series of CPBA-HPCS with different substitution degrees（up to 0.78） was prepared. This novel chitosan derivative has good application prospects in the preparation of smart hydrogels and drug carriers. Table and Figures | Reference | Related Articles | Metrics

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Molecular Stacking and Device Performance： Recent Advances of Efficient Small Molecule Donors Based on Benzodithiophene and Its Derivatives YANG Ke, XIAO Zeyun, LU Shirong, SUN Kuan Chem. J. Chinese Universities    2023, 44 (9): 20230123-.   DOI: 10.7503/cjcu20230123 Abstract （563）   HTML （20）    PDF（pc） （7096KB）（4420）       Knowledge map    Save The rapid development of all-small-molecule solar cell has recently gained recognition within the photovoltaic research community. Well-defined structure and less batch-to-batch variation empowered it great application prospects. In this perspective， we review the development of small molecule donors based on benzodithiophene（BDT） and its derivatives， with a focus on the relationship between molecule structure， stacking characteristics and device performance. By analyzing successful cases in the BDT series of small molecules， we aim to clarify the link between molecule structure， solid-state aggregation and device performance. We hope this discussion can be the minnow to catch the whale of highly efficient molecules in the future. Table and Figures | Reference | Related Articles | Metrics

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Advances in Alloy-based High-capacity Li-containing Anodes for Lithium-ion Batteries MAO Eryang, WANG Li, SUN Yongming Chem. J. Chinese Universities    2021, 42 (5): 1552-1568.   DOI: 10.7503/cjcu20200750 Abstract （1783）   HTML （104）    PDF（pc） （7469KB）（5366）       Knowledge map    Save The emergent Li-containing alloys（LixMy， M refers to metal or nonmetal element that can react with Li to form alloys） is a class of promising electrode materials for next-generation high energy lithium-ion batteries. They deliver high theoretical specific capacities that are several times that of current graphite and can act as active lithium suppliers that are different from traditional lithium-free alloy anodes（Si， Sn， P， etc.）. The LixMy anodes can pare with high-capacity Li-free cathodes（such as Sulfur， O2， FeF3， V2O5， etc.） to develop a new full battery system. In this paper， researches on Li-containing alloy-based high-capacity anodes LixMy（e.g.， Li4.4Si， Li4.4Sn， Li3P， Li2.25Al， etc.） were reviewed. Scientific challenges and technical difficulties of LixMy anodes were systematically analyzed and discussed. Various methods for materials synthesis and electrodes fabrication were summarized. Furthermore， various full-cell configurations based on LixMy anodes were introduced， including Li-ion batteries（LIBs）， Li-ion-sulfur batteries（LISBs）， and Li-ion-oxygen batte-ries（LIOBs）. Moreover， research strategies and achievements on addressing the challenges of LixMy anodes and improving their performance were discussed， including composition adjustment， surface coating， material composite， electrode treatment， and electrolyte engineering， etc. Also， perspectives and new insights for the future development of LixMy anodes are proposed. Table and Figures | Reference | Related Articles | Metrics

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Functions of Plant RNA Modifications and Their Analytical Methods TANG Xiaomeng, YUAN Bifeng, FENG Yuqi Chem. J. Chinese Universities    2023, 44 (3): 20220265-.   DOI: 10.7503/cjcu20220265 Abstract （761）   HTML （26）    PDF（pc） （3104KB）（3737）       Knowledge map    Save Apart from the canonical nucleobases， RNA molecules contain a variety of chemical modifications. So far， over 150 different types of RNA modifications have been identified in the three-domain system of life. These chemical modifications do not alter the sequence of RNA， but they can change the structures and biochemical properties of RNA， which thereby can control and regulate the spatiotemporal expression of genes. As an important epigenetic regulation layer， RNA modifications also play crucial roles in regulating plant growth and development and respond to stresses. In recent years， with the rapid advancement of analytical methods， especially the technologies for RNA modification sequencing， the functions and mechanisms of plant RNA modifications have gained in-depth understanding. In the current review， we introduce the functions of plant RNA modifications and summarize the analytical methods for plant RNA modifications. We believe that this review will provide useful information for the systematic study of plant RNA modifications in the future. Table and Figures | Reference | Related Articles | Metrics

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Research Progress of Controllable Self-assembled DNA Origami Structure as Drug Carrier WU Yushuai, SHANG Yingxu, JIANG Qiao, DING Baoquan Chem. J. Chinese Universities    2022, 43 (8): 20220179-.   DOI: 10.7503/cjcu20220179 Abstract （1137）   HTML （56）    PDF（pc） （9692KB）（3426）       Knowledge map    Save In the past few decades， structural DNA nanotechnology， as a rapidly developing， controllable self- assembling strategy， enables the design and construction of a variety of sophisticated nanostructures. Particularly， DNA origami structures feature unique properties， such as rationally designed geometry， precise spatial addressabi?lity， easy of modification and good biocompatibility， which provide them with broad prospects in drug delivery. In this minireview， the research progresses of drug delivery systems based on the DNA origami technique were summarized. The future development prospects of DNA origami nanocarriers and remaining challenges in this field were also discussed. Table and Figures | Reference | Related Articles | Metrics

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Research Progress of CO2 Hydrogenation over Pd-based Heterogeneous Catalysts ZHOU Leilei, CHENG Haiyang, ZHAO Fengyu Chem. J. Chinese Universities    2022, 43 (7): 20220279-.   DOI: 10.7503/cjcu20220279 Abstract （1020）   HTML （47）    PDF（pc） （3133KB）（3617）       Knowledge map    Save With the continuous increase of carbon dioxide（CO2） emissions， the impact of global warming and climate change on human life and ecological environment has become more serious. As a cheap and renewable carbon and oxygen resource， converting CO2 into high value-added chemicals is one of the shining research topics in the field of green chemistry and energy， and has received extensive attention. The Pd-based catalysts are one kind of the most promising catalysts of CO2 catalytic conversion due to its excellent hydrogenation capacity， good stability， anti- sintering and anti-poisoning properties. This paper will review the research progress of the hydrogenation of CO2 over Pd-based catalysts to synthesis small energy molecule compounds such as HCOOH， CO， CH4 and methanol. We will pay main attention to the discussion of the active sites for the adsorption/activation of CO2 molecule， strong metal- support interaction， surface and interface composition， which affect the activity and selectivity of Pd-based catalysts， as well as the catalytic mechanism over Pd-based catalysts. Table and Figures | Reference | Related Articles | Metrics

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Solvent Effect on the Catalytic Performance of Cinnamaldehyde Hydrogenation over Pt/MIL-100（Fe） CAI Jiani, LIU Yingya, SUN Zhichao, WANG Yao, WANG Anjie Chem. J. Chinese Universities    2024, 45 (2): 20230442-.   DOI: 10.7503/cjcu20230442 Abstract （560）   HTML （16）    PDF（pc） （3974KB）（2890）       Knowledge map    Save This study employs an environmentally-friendly method to synthesize MIL-100（Fe）， and utilizes a double-solvent impregnation approach to confine Pt nanoparticles within the pores of MIL-100（Fe）， subsequent to acidification with HCl and reduction with formaldehyde， a bifunctional catalyst， Pt/MIL-100（Fe）， featuring hydrogenation and Lewis acid centers， is prepared. The catalytic performance is evaluated using the selective hydrogenation of cinnamaldehyde（CAL） as a probe reaction. Under optimal conditions（60 ℃， 1 MPa H2）， the conversion of CAL reaches 88.3% in 2 h， with a cinnamyl alcohol（COL） selectivity of 84.9%. By comparing the reaction performance of Pt/MIL-100 catalysts with Cr， Al and Fe metal centers， it is revealed that the Fe center favors for the hydrogenation of C=O bonds in both CAL to COL and furfural to furfuryl alcohol. The impact of water content in the reaction system on the selective hydrogenation of CAL is extensively studied. Characterization and static adsorption experiments indicate that removal of free water from the pores of Pt/MIL-100（Fe） facilitates direct enrichment of CAL in the channels， leading to an enhanced conversion. Additionally， removal of coordinated water from the Fe cluster promotes the adsorption of the C=O group of CAL， resulting in an improved selectivity toward COL. After five catalytic cycles under optimal conditions， Pt/MIL-100（Fe） maintains the catalytic performance. Results of powder X-ray diffraction （XRD）， transmission electron microscopy （TEM）， and low-temperature nitrogen adsorption characterization confirm the stability of the catalyst structure after reaction. Table and Figures | Reference | Supplementary Material | Related Articles | Metrics

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Green Electrosynthesis Reaction of Potassium Azotetrazolium Salt Coupled by Hydrogen Production from Water Electrolysis by WS2 Nano Sheets YAO Tianhao, MA Yuhe, LIU Bolong, MA Yuqiang, ZHANG Cong, LI Jiachen, MA Haixia Chem. J. Chinese Universities    2023, 44 (12): 20230347-.   DOI: 10.7503/cjcu20230347 Abstract （662）   HTML （10）    PDF（pc） （5908KB）（2883）       Knowledge map    Save As a four-electron multi-step reaction process with sluggish kinetics， oxygen evolution reaction（OER） limits the reaction rate and reduces the overall efficiency of overall water splitting. Replacing OER with the oxidation reaction of thermodynamically more favorable organic energetic materials and coupling with hydrogen evolution reaction（HER）， so that the high value-added chemical products can be obtained while reducing the overall cell voltage to generate hydrogen. In this paper， a novel coupling system was proposed， in which the energy-containing ionic salt， potassium azotetrazolium salt（K2AZT）， was prepared on the anode side， and carbon cloth-supported tungsten disulfide nanosheets（CC@WS2 NSs） were used as HER catalyst to promote the HER on the cathode side. The system only requires a cell voltage of 1.65 V to achieve a current density of 10 mA/cm 2， which is 220 mV lower than that of conventional electrolyzed water（1.87 V）. In addition， the coupled system maintained smooth operation for at least 15 h， showing excellent stability. At the same time， the preparation of energetic compounds by green and safe electrochemical method avoids the problems of high energy consumption， high risk and high cost of traditional organic synthesis method， and provides a new synthesis strategy for the safe production of energetic materials. Table and Figures | Reference | Supplementary Material | Related Articles | Metrics

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Split Intein： a Versatile Tool for Traceless Peptide Segment Ligation HAN Dongyang, REN Yuxiang, YANG Ziyi, HUANG He, ZHENG Jishen Chem. J. Chinese Universities    2023, 44 (10): 20230188-.   DOI: 10.7503/cjcu20230188 Abstract （1895）   HTML （98）    PDF（pc） （5394KB）（2982）       Knowledge map    Save Split intein can efficiently ligate peptide segments via a splicing reaction in a traceless manner and therefore has attracted great attention. Based on the structural characteristics and splicing reaction process of split intein， this paper comprehensively reviewed the recent progresses on the performance optimization and expanded applications of split intein， and revealed its great potential in the field of chemical protein synthesis as an increasingly sophisticated protein engineering technology. Finally， the challenges presented in the split intein- mediated protein trans-splicing and potential solutions in the future research were briefly discussed. Table and Figures | Reference | Related Articles | Metrics

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CO2-involved Electrochemical C—N Coupling into Value-added Chemicals WANG Ruhan, JIA Shunhan, WU Limin, SUN Xiaofu, HAN Buxing Chem. J. Chinese Universities    2022, 43 (7): 20220395-.   DOI: 10.7503/cjcu20220395 Abstract （841）   HTML （32）    PDF（pc） （5957KB）（2637）       Knowledge map    Save CO2 is the main greenhouse gas and an important C1 resource. C—N bonds formation plays an important role in chemical industry， biosynthesis and medicine. In recent years， with the deepening of carbon neutrality and green chemistry concept， the strategy of electrochemical C—N bonds construction has attracted much attention due to its advantages of environmental benign， low carbon， simplicity and green. At the same time， continuous consumption of fossil resource results in a series of environmental and resource problems， and the green sustainable synthesis of important chemicals and fuels is attracting increasing attention. This paper focuses on the research progress of CO2-involved electrochemical C—N formation to prepare important chemicals. The electrochemical synthesis of urea， amide and amine are reviewed from the perspectives of catalytic system construction， reaction processes， and reaction mechanism. Finally， the critical challenges remaining in this research area and promising directions for future research are discussed. Table and Figures | Reference | Related Articles | Metrics

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Applications of Metal-organic Framework-based Material in Carbon Dioxide Photocatalytic Conversion ZHAO Yingzhe, ZHANG Jianling Chem. J. Chinese Universities    2022, 43 (7): 20220223-.   DOI: 10.7503/cjcu20220223 Abstract （1127）   HTML （32）    PDF（pc） （4990KB）（2818）       Knowledge map    Save Converting carbon dioxide（CO2） into fuels or high-additional-valued chemicals is an efficient route to decrease atmospheric CO2 concentration and mitigate green-house effect. Particularly， the photocatalytic CO2 conversion is of importance due to its mild reaction condition and low energy consumption. Metal-organic framework-based（MOF-based） materials are a kind of efficient catalyst for CO2 photocatalytic conversion owing to their unique features such as large specific surface area， good photoelectric properties and various tunability. In this article， the applications of MOF-based materials in CO2 photocatalytic reduction， cycloaddition and carboxylation in recent two years were reviewed. The advantages， limitations and future development of MOF-based materials for photocatalytic CO2 conversion reactions were discussed. Table and Figures | Reference | Related Articles | Metrics

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Application of 2D NMR in Organic Photovoltaics CHEN Hongru, BAI Yang, ZHOU Qiuju, ZHANG Zhiguo Chem. J. Chinese Universities    2023, 44 (7): 20230104-.   DOI: 10.7503/cjcu20230104 Abstract （619）   HTML （18）    PDF（pc） （8803KB）（2333）       Knowledge map    Save Two-dimensional nuclear magnetic resonance technique（2D NMR） plays a crucial role in the structural analysis of complex organic compounds. Analyzing the correlation signals of 2D NMR spectra could help us obtain the information about intra- and inter-molecular interactions. Meanwhile， it is significant to study molecular interaction between photoactive layer materials for organic photovoltaics. Such interaction can help us not only analyze the aggregation behavior of molecules， but also understand the changes in the morphology and stability of the active layer upon the addition of a third component. In this review， we provide relevant introduction on the 2D NMR spectrum， and summarize the related works on the use of 2D NMR in the analyzing the interaction between molecules in organic solar cells. Finally， It offers a perspective on the future development in this technique. Table and Figures | Reference | Related Articles | Metrics

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High-efficiency Near-infrared Thermally Activated Delayed Fluorescence Based on Tetracyano Acceptor WANG Xiaojing, LIU Yixia, LI Yang, YANG Chenzong, FUNG Mankeung, FAN Jian Chem. J. Chinese Universities    2023, 44 (12): 20230274-.   DOI: 10.7503/cjcu20230274 Abstract （579）   HTML （37）    PDF（pc） （2629KB）（2343）       Knowledge map    Save The near-infrared thermally activated delayed fluorescence（TADF） material 11，12-bis［4-（diphenyla- min）phenyl］dipyrido［3，2-a：2'，3'-c］phenazine-3，6，10，13-tetracarbonitrile（FCNPZ-TPA） was designed and synthesized with dipyridinophenazine as the acceptor unit and triphenylamine（TPA） as the donor unit. The introduction of four cyano groups into the acceptor unit increased its electron-withdrawing strength. Considering that tripheny-lamine is a strong electron-donating group， we successfully pushed the emission of FCNPZ-TPA into Near Infra（NIR） region via the incorporation of strong donor and strong acceptor. The steric hindrance between donor（D） and acceptor（A） led to a twisted D-A molecular configuration of FCNPZ-TPA， and thus achieving a small singlet-triplet energy gap（ΔEST）. Due to the rigid molecular skeleton and small ΔEST， FCNPZ-TPA based organic light-emitting diode（OLED） exhibited a state-of-the-art maximum external quantum efficiency（EQE） of 8.01% at 742 nm when doped in the 4，4'-bis（N-carbazolyl）-1，1'-biphenyl. Table and Figures | Reference | Related Articles | Metrics

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Electrochemiluminescence of Quantum Dots: Research Progress and Future Perspectives CAO Zhiyuan, SUN Hui, SU Bin Chem. J. Chinese Universities    2020, 41 (9): 1945-1955.   DOI: 10.7503/cjcu20200390 Abstract （2149）   HTML （66）    PDF（pc） （5697KB）（2843）       Knowledge map    Save Electrochemiluminescence(ECL) has become one of the most advanced immunodiagnostic method due to its near-zero background and high sensitivity. Ruthenium(Ⅱ) tris(bipyridine)[Ru(bpy)32+] and its derivatives have been applied in commercial diagnostics, but their optical properties can not meet the requirement of state-of-art ECL analysis. Quantum dots(QDs) possess outstanding luminescence properties and seem to be ideal for developing a new generation of ECL emitters. However, the mechanism of ECL generation from QDs deserves further in-depth investigations and the ECL performance of QDs also needs to be improved. In this review, we focus on the important advancements and key scientific issues of QDs ECL. After an overview of the developments of the field, future perspectives about the developments of QDs ECL are also exhibited. We believe that spectroscopy, synthesis chemistry and electrochemistry should be combined together to advance the research. Table and Figures | Reference | Related Articles | Metrics

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Research Progress on the Synthesis of Pillar[n]arenes and Their Host-guest Chemistry WANG Kai, YANG Ying-Wei, ZHANG Sean Xiao-An Chem. J. Chinese Universities    2012, 33 (01): 1-13.   DOI: 10.3969/j.issn.0251-0790.2012.01.001 Abstract （8209）      PDF（pc） （951KB）（4986）       Knowledge map    Save Pillararenes are a new class of host molecules, which are cyclic oligomers consisting of hydroquinones or 1,4-disubstituted hydroquinone ethers linked by methylene bridges in the para positions of the benze rings. Herein, recent development on the synthesis of pillar[n]arenes and pillar[n]arene derivatives, and their host-guest chemistry, i.e., molecular recognition and selective binding towards guest molecules, and their self-assembly properties was reviewed. In addition, prospects for future research based on pillar[n]arenes were also discussed. Reference | Related Articles | Metrics

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Design and Construction of UiO-66-NH2/wood Composite for Efficient Removal of Trace Heavy Metal Ions from Water LI Hua, YANG Ke, HUANG Junfeng, CHEN Fengjuan Chem. J. Chinese Universities    2022, 43 (3): 20210701-.   DOI: 10.7503/cjcu20210701 Abstract （1115）   HTML （27）    PDF（pc） （5440KB）（2295）       Knowledge map    Save UiO-66-NH2 Metal-Organic-Frameworks（MOFs） nanoparticles were in situ formed in the 3D low-tortuosity wood lumens by a facile solve-thermal strategy with ZrCl4 and amino terephthalic acid as precursors. The UiO-66-NH2/wood membrane showed excellent removal performance for removing heavy metal ions（Hg2+， Cu2+） in wastewater. The results showed that the removal efficiency for tested heavy metal ions（Hg2+， Cu2+） is more than 90.0% at the treatment rate of 1.0×102 L?m-2?h-1. Wood membrane， as a 3D substrate for anchoring UiO-66-NH2 nanoparticles， contains numerous elongated and open lumens along the growth direction. On the one hand， it can enhance the water of including heavy metal ions fluxes； on the other hand， it can increase the contact probability of heavy metal ion containments with UiO-66-NH2 MOFs as water flowing through the membrane. Therefore， the UiO-66-NH2/wood membrane can efficiently remove trace heavy metal ions from the water. In addition， the UiO-66-NH2/wood membrane also has good reusability， which is expected to be applied in practical applications. Table and Figures | Reference | Related Articles | Metrics

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Sequencing Methods for Detection of Nucleic Acid Epigenetic Modifications FANG Xin, ZHAO Ruiqi, MO Jing, WANG Yafen, WENG Xiaocheng Chem. J. Chinese Universities    2023, 44 (3): 20220342-.   DOI: 10.7503/cjcu20220342 Abstract （1020）   HTML （44）    PDF（pc） （9770KB）（2409）       Knowledge map    Save All the somatic cells in an organism share the same genetic information， but have different RNA expression subsets. Only part of genes are expressed and perform their functions at a specific time. In recent years， breakthroughs in epigenetic research have helped people understand the regulation of gene expression to a certain extent. Three types of biological macromolecules： DNA， RNA， and protein， are chemically modified after synthesis. These modifications involve the regulation of almost all biological processes. So far， researchers have identified more than 17 and 160 chemical modifications in DNA and RNA， respectively. The interest in various biological functions of DNA and RNA modifications has promoted the development of the frontier fields of epigenomics and epigenomics. Developing chemical and biological tools to detect specific modifications in the genome or transcriptome is an issue of great concern to us， and it is also a key to the research of epigenomics and epitranscriptomics. Herein， we summarize the detection methods of nucleic acid modifications， and put forward some bottlenecks in the existing technologies and possible innovative methods. Table and Figures | Reference | Related Articles | Metrics

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Fabrication and Properties of Epoxy Vitrimer Based on Multiply Dynamic Covalent Bonds YANG Weiming, XI Aoqian, YANG Bin, ZENG Yanning Chem. J. Chinese Universities    2022, 43 (11): 20220308-.   DOI: 10.7503/cjcu20220308 Abstract （875）   HTML （39）    PDF（pc） （8349KB）（3134）       Knowledge map    Save Traditional epoxy networks were wildly applied in composites， adhesives， coatings， electronic packaging and insulating materials， due to their excellent properties and stable network structure. However， once epoxy networks are formed， they cannot be reprocessed. When epoxy networks are damaged during the serving time， they cannot be self-healed. Epoxy vitrimers networks with dynamic reversible covalent bonds can reorganized their network typology under external stimuli， contributing to network reprocessing and self-healing. Currently， most epoxy vitrimers show a high temperature for reprocessing and self-healing， consuming high energy. Herein， the epoxy vitrimers with tri-dynamic covalent bonds（boronic ester bond， disulfide bond and ester bond） were fabricated by epoxy-thiol “click” reaction and epoxy-carboxylic acid reaction. The structures of the prepared epoxy vitrimers were characterized by Fourier transform Infrared spectrometer（FTIR） and Raman spectroscopy， and hydrogen bonds were found in the prepared epoxy vitrimers contributing to improvement of crosslink density. Meanwhile， the thermal stability， thermo-mechanical properties and mechanical properties of the prepared epoxy vitrimers were investigated by thermogravimetry（TG）， dynamic mechanical analysis（DMA） and tensile testing. Furthermore， self-healing， welding， shape memory and reprocessing capabilities of the prepared epoxy vitrimers were researched. The results display that at 80 ℃ the scratches on the prepared epoxy vitrimers can be fully recovered and the welding recovery of tensile strength of the prepared epoxy vitrimers is >80%， indicating excellent functionality. Table and Figures | Reference | Related Articles | Metrics