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A layered multifunctional framework based on polyacrylonitrile and MOF derivatives for stable lithium metal anode
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作者 Fanfan Liu Peng Zuo +5 位作者 Jing Li Pengcheng Shi Yu Shao Linwei Chen Yihong Tan Tao Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期282-288,I0007,共8页
Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition be... Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li ions.To promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical conductivity.Profiting from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~2.Besides,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical cells.When the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 cycles.Moreover,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction design.These electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks. 展开更多
关键词 Lithium metal anode Layered multifunctional framework Ions flux redistribution Electrical insulation/conduction structure Uniform Li deposition
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Optimizing the morphology of all-polymer solar cells for enhanced photovoltaic performance and thermal stability
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作者 Kang An Wenkai Zhong +8 位作者 Chunguang Zhu Feng Peng Lei Xu Zhiwei Lin Lei Wang Cheng Zhou Lei Ying Ning Li Fei Huang 《Journal of Semiconductors》 EI CAS CSCD 2023年第5期34-41,共8页
Due to the complicated film formation kinetics, morphology control remains a major challenge for the development of efficient and stable all-polymer solar cells(all-PSCs). To overcome this obstacle, the sequential dep... Due to the complicated film formation kinetics, morphology control remains a major challenge for the development of efficient and stable all-polymer solar cells(all-PSCs). To overcome this obstacle, the sequential deposition method is used to fabricate the photoactive layers of all-PSCs comprising a polymer donor PTzBI-oF and a polymer acceptor PS1. The film morphology can be manipulated by incorporating amounts of a dibenzyl ether additive into the PS1 layer. Detailed morphology investigations by grazing incidence wide-angle X-ray scattering and a transmission electron microscope reveal that the combination merits of sequential deposition and DBE additive can render favorable crystalline properties as well as phase separation for PTzBI-oF:PS1 blends. Consequently, the optimized all-PSCs delivered an enhanced power conversion efficiency(PCE) of 15.21%along with improved carrier extraction and suppressed charge recombination. More importantly, the optimized all-PSCs remain over 90% of their initial PCEs under continuous thermal stress at 65 °C for over 500 h. This work validates that control over microstructure morphology via a sequential deposition process is a promising strategy for fabricating highly efficient and stable all-PSCs. 展开更多
关键词 MORPHOLOGY all-polymer solar cells thermal stability sequential deposition
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Modified electronic structure and enhanced hydroxyl adsorption make quaternary Pt-based nanosheets efficient anode electrocatalysts for formic acid-/alcohol-air fuel cells
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作者 Fengling Zhao Qiang Yuan +2 位作者 Siyang Nie Liang Wu Xun Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期142-150,共9页
Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet challenging.Herein,using visible light,a class of quaternary Pt_(1)... Surface/interface engineering of a multimetallic nanostructure with diverse electrocatalytic properties for direct liquid fuel cells is desirable yet challenging.Herein,using visible light,a class of quaternary Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)ultrathin nanosheets is fabricated and used as high-performance anode electrocatalysts for formic acid-/alcohol-air fuel cells.The modified electronic structure of Pt,enhanced hydroxyl adsorption,and abundant exterior defects afford Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C high intrinsic anodic electrocatalytic activity to boost the power densities of direct formic acid-/methanol-/ethanol-/ethylene glycol-/glycerol-air fuel cells,and the corresponding peak power density of Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C is respectively 129.7,142.3,105.4,124.3,and 128.0 mW cm^(-2),considerably outperforming Pt/C.Operando in situ Fourier transform infrared reflection spectroscopy reveals that formic acid oxidation on Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)/C occurs via a CO_(2)-free direct pathway.Density functional theory calculations show that the presence of Ag,Bi,and Te in Pt_(1)Ag_(0.1)Bi_(0.16)Te_(0.29)suppresses CO^(*)formation while optimizing dehydrogenation steps and synergistic effect and modified Pt effectively enhance H_(2)O dissociation to improve electrocatalytic performance.This synthesis strategy can be extended to 43 other types of ultrathin multimetallic nanosheets(from ternary to octonary nanosheets),and efficiently capture precious metals(i.e.,Pd,Pt,Rh,Ru,Au,and Ag)from different water sources. 展开更多
关键词 Pt-based nanosheets Modifiedelectronic structure Enhanced hydroxyl adsorption Formicacidand alcohol oxidation Direct liquid fuel cells
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A review of ^(17)O isotopic labeling techniques for solid-state NMR structural studies of metal oxides in lithium-ion batteries
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作者 Xiaoli Xia Lei Zhu +2 位作者 Weiping Tang Luming Peng Junchao Chen 《Magnetic Resonance Letters》 2024年第2期46-53,共8页
Recent advances in utilizing ^(17)O isotopic labeling methods for solid-state nuclear magnetic resonance(NMR)investigations of metal oxides for lithium-ion batteries have yielded extensive insights into their structur... Recent advances in utilizing ^(17)O isotopic labeling methods for solid-state nuclear magnetic resonance(NMR)investigations of metal oxides for lithium-ion batteries have yielded extensive insights into their structural and dynamic details.Herein,we commence with a brief introduction to recent research on lithium-ion battery oxide materials studied using ^(17)O solid-state NMR spectroscopy.Then we delve into a review of ^(17)O isotopic labeling methods for tagging oxygen sites in both the bulk and surfaces of metal oxides.At last,the unresolved problems and the future research directions for advancing the ^(17)O labeling technique are discussed. 展开更多
关键词 ^(17)O solid-state NMR ^(17)O isotopic labeling methods Bulk and surfaces of metal oxides DFT calculation
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Improved dissolution and bioavailability of silymarin delivered by a solid dispersion prepared using supercritical fluids 被引量:6
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作者 Gang Yang Yaping Zhao +3 位作者 Nianping Feng Yongtai Zhang Ying Liu Beilei Dang 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2015年第3期194-202,共9页
The objective of this study was to improve the dissolution and bioavailability of silymarin(SM).Solid dispersions(SDs)were prepared using solution-enhanced dispersion by supercritical fluids(SEDS)and evaluated in vitr... The objective of this study was to improve the dissolution and bioavailability of silymarin(SM).Solid dispersions(SDs)were prepared using solution-enhanced dispersion by supercritical fluids(SEDS)and evaluated in vitro and in vivo,compared with pure SM powder.The particle sizes,stability,and contents of residual solvent of the prepared SM-SDs with SEDS and solvent evaporation(SE)were investigated.Four polymer matrix materials were evaluated for the preparation of SM-SD-SEDS,and the hydrophilic polymer,polyvinyl pyrrolidone K17,was selected with a ratio of 1:5 between SM and the polymer.Physicochemical analyses using X-ray diffraction and differential scanning calorimetry indicated that SM was dispersed in SD in an amorphous state.The optimized SM-SD-SEDS showed no loss of SM after storage for 6 months and negligible residual solvent(ethanol)was detected using gas chromatography.In vitro drug release was increased from the SM-SDSEDS,as compared with pure SM powder or SM-SD-SE.In vivo,the area under the rat plasma SM concentration-time curve and the maximum plasma SM concentration were 2.4-fold and 1.9-fold higher,respectively,after oral administration of SM-SD-SEDS as compared with an aqueous SM suspension.These results illustrated the potential of using SEDS to prepare SM-SD,further improving the biopharmaceutical properties of this compound. 展开更多
关键词 SILYMARIN Solution-enhanced dispersion by supercritical fluids Solid dispersion DISSOLUTION BIOAVAILABILITY
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Reduction and carburization of iron oxides for Fischer–Tropsch synthesis 被引量:2
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作者 Monia Runge Nielsen Asger Barkholt Moss +11 位作者 Anton Simon Bjrnlund Xi Liu Axel Knop-Gericke Alexander YuKlyushin Jan-Dierk Grunwaldt Thomas LSheppard Dmitry EDoronkin Anna Zimina Thomas Eric Lyck Smitshuysen Christian Danvad Damsgaard Jakob Birkedal Wagner Thomas Willum Hansen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第12期48-61,共14页
The activation of iron oxide Fischer–Tropsch Synthesis(FTS) catalysts was investigated during pretreatment: reduction in hydrogen followed by carburization in either CO or syngas mixture, or simultaneously reduction ... The activation of iron oxide Fischer–Tropsch Synthesis(FTS) catalysts was investigated during pretreatment: reduction in hydrogen followed by carburization in either CO or syngas mixture, or simultaneously reduction and carburization in syngas. A combination of different complementary in situ techniques was used to gain insight into the behavior of Fe-based FTS catalysts during activation. In situ XRD was used to identify the crystalline structures present during both reduction in hydrogen and carburization. An increase in reduction rate was established when increasing the temperature. A complete reduction was demonstrated in the ETEM and a grain size dependency was proven, i.e. bigger grains need higher temperature in order to reduce. XPS and XAS both indicate the formation of a small amount of carbonaceous species at the surface of the bulk metallic iron during carburization. 展开更多
关键词 In situ characterization Fischer–Tropsch Catalyst reduction and carburization Iron oxides
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Understanding the synergistic effect of mixed solvent annealing on perovskite film formation
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作者 钱昆 李渝 +6 位作者 宋静楠 Jazib Ali 张明 朱磊 丁虹 詹俊哲 冯威 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期631-636,共6页
Morphology control of perovskite films is of critical importance for high-performance photovoltaic devices. Although solvent vapor annealing(SVA) treatment has been widely used to improve the film quality efficiently,... Morphology control of perovskite films is of critical importance for high-performance photovoltaic devices. Although solvent vapor annealing(SVA) treatment has been widely used to improve the film quality efficiently, the detailed mechanism of film growth is still under construction, and there is still no consensus on the selection of solvents and volume for further optimization. Here, a series of solvents(DMF, DMSO, mixed DMF/DMSO) were opted for exploring their impact on fundamental structural and physical properties of perovskite films and the performance of corresponding devices. Mixed solvent SVA treatment resulted in unique benefits that integrated the advantages of each solvent, generating a champion device efficiency of 19.76% with improved humidity and thermal stability. The crystallization mechanism was constructed by conducting grazing-incidence wide-angle x-ray diffraction(GIWAXS) characterizations, showing that dissolution and recrystallization dominated the film formation. A proper choice of solvent and its volume balancing the two processes thus afforded the desired perovskite film. This study reveals the underlying process of film formation, paving the way to producing energy-harvesting materials in a controlled manner towards energy-efficient and stable perovskite-based devices. 展开更多
关键词 perovskite solar cell solvent vapor annealing DISSOLUTION RECRYSTALLIZATION
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Photothermal-chemical synthesis of P-S-H ternary hydride at high pressures
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作者 叶婷婷 曾鸿 +4 位作者 程鹏 姚德元 潘孝美 张晓 丁俊峰 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期650-655,共6页
The recent discovery of room temperature superconductivity(283 K)in carbonaceous sulfur hydride(C-S-H)has attracted much interest in ternary hydrogen rich materials.In this report,ternary hydride P-S-H was synthesized... The recent discovery of room temperature superconductivity(283 K)in carbonaceous sulfur hydride(C-S-H)has attracted much interest in ternary hydrogen rich materials.In this report,ternary hydride P-S-H was synthesized through a photothermal-chemical reaction from elemental sulfur(S),phosphorus(P)and molecular hydrogen(H_(2))at high pressures and room temperature.Raman spectroscopy under pressure shows that H_(2)S and PH_(3) compounds are synthesized after laser heating at 0.9 GPa,and a ternary van der Waals compound P-S-H is synthesized with further compression to 4.6 GPa.The P-S-H compound is probably a mixed alloy of PH_(3) and(H_(2)S)_(2)H_(2) with a guest-host structure similar to the C-S-H system.The ternary hydride can persist up to 35.6 GPa at least and shows two phase transitions at approximately 23.6 GPa and 32.8 GPa,respectively. 展开更多
关键词 HYDRIDE SUPERCONDUCTOR high pressure Raman spectroscopy
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Influence of dielectric barrier discharge treatment on mechanical and dyeing properties of wool
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作者 Rahul NAVIK Sameera SHAFI +3 位作者 Md Miskatul ALAM Md Amjad FAROOQ 林丽娜 蔡映杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第6期89-98,共10页
Physical and chemical properties of wool surface significantly affect the absorbency,rate of dye bath exhaustion and fixation of the industrial dyes.Hence,surface modification is a necessary operation prior to colorat... Physical and chemical properties of wool surface significantly affect the absorbency,rate of dye bath exhaustion and fixation of the industrial dyes.Hence,surface modification is a necessary operation prior to coloration process in wool wet processing industries.Plasma treatment is an effective alternative for physiochemical modification of wool surface.However,optimum processing parameters to get the expected modification are still under investigation,hence this technology is still under development in the wool wet processing industries.Therefore,in this paper,treatment parameters with the help of simple dielectric barrier discharge plasma reactor and air as a plasma gas,which could be a promising combination for treatment of wool substrate at industrial scale were schematically studied,and their influence on the water absorbency,mechanical,and dyeing properties of twill woven wool fabric samples are reported.It is expected that the results will assist to the wool coloration industries to improve the dyeing processes. 展开更多
关键词 air plasma reactive dye surface energy wool
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Design, Synthesis and Inhibitory Properties against Coxsackie B3/B6 of Some Novel Triazole Derivatives
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作者 Dongping Shao Yanbing Yang +5 位作者 Fei Xue Xianjin Luo Reyila Wubulikasimu Yuhuan Li Rongmei Gao Weidong Ye 《International Journal of Organic Chemistry》 2013年第1期41-46,共6页
A series of 1,2,4-triazole derivatives were synthesized, and their abilities to inhibit the in vitro replication of Coxsackie B3/B6 were evaluated. Among the 1,2,4-triazole derivatives, compound 3 g displayed potent a... A series of 1,2,4-triazole derivatives were synthesized, and their abilities to inhibit the in vitro replication of Coxsackie B3/B6 were evaluated. Among the 1,2,4-triazole derivatives, compound 3 g displayed potent activity, with a high antiviral potency (IC50 = 1.71 μM (against CVB3), 1.43 μM (against CVB6)). The structures of all the new synthesized compounds were confirmed by 1H-NMR spectra, mass spectra and elemental analyses. 展开更多
关键词 1 2 4-Triazole Anti-Enterovirus COXSACKIE B Viruses
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2D Materials Boost Advanced Zn Anodes:Principles,Advances,and Challenges
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作者 Songhe Zheng Wanyu Zhao +3 位作者 Jianping Chen Xiaoli Zhao Zhenghui Pan Xiaowei Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第4期1-22,共22页
Aqueous zinc-ion battery(ZIB)featuring with high safety,low cost,environmentally friendly,and high energy density is one of the most promising systems for large-scale energy storage application.Despite extensive resea... Aqueous zinc-ion battery(ZIB)featuring with high safety,low cost,environmentally friendly,and high energy density is one of the most promising systems for large-scale energy storage application.Despite extensive research progress made in developing high-performance cathodes,the Zn anode issues,such as Zn dendrites,corrosion,and hydrogen evolution,have been observed to shorten ZIB’s lifespan seriously,thus restricting their practical application.Engineering advanced Zn anodes based on two-dimensional(2D)materials are widely investigated to address these issues.With atomic thickness,2D materials possess ultrahigh specific surface area,much exposed active sites,superior mechanical strength and flexibility,and unique electrical properties,which confirm to be a promising alternative anode material for ZIBs.This review aims to boost rational design strategies of 2D materials for practical application of ZIB by combining the fundamental principle and research progress.Firstly,the fundamental principles of 2D materials against the drawbacks of Zn anode are introduced.Then,the designed strategies of several typical 2D materials for stable Zn anodes are comprehensively summarized.Finally,perspectives on the future development of advanced Zn anodes by taking advantage of these unique properties of 2D materials are proposed. 展开更多
关键词 Zinc-ion battery Large-scale energy storage application Zn anode LIFESPAN 2D materials
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Quantitative measurement of the charge carrier concentration using dielectric force microscopy
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作者 赖君奇 陈博文 +4 位作者 邢志伟 李雪飞 陆书龙 陈琪 陈立桅 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期449-455,共7页
The charge carrier concentration profile is a critical factor that determines semiconducting material properties and device performance.Dielectric force microscopy(DFM)has been previously developed to map charge carri... The charge carrier concentration profile is a critical factor that determines semiconducting material properties and device performance.Dielectric force microscopy(DFM)has been previously developed to map charge carrier concentrations with nanometer-scale spatial resolution.However,it is challenging to quantitatively obtain the charge carrier concentration,since the dielectric force is also affected by the mobility.Here,we quantitative measured the charge carrier concentration at the saturation mobility regime via the rectification effect-dependent gating ratio of DFM.By measuring a series of n-type GaAs and GaN thin films with mobility in the saturation regime,we confirmed the decreased DFM-measured gating ratio with increasing electron concentration.Combined with numerical simulation to calibrate the tip–sample geometry-induced systematic error,the quantitative correlation between the DFM-measured gating ratio and the electron concentration has been established,where the extracted electron concentration presents high accuracy in the range of 4×10^(16)–1×10^(18)cm^(-3).We expect the quantitative DFM to find broad applications in characterizing the charge carrier transport properties of various semiconducting materials and devices. 展开更多
关键词 dielectric force microscopy charge carrier concentration quantitative measurement numerical simulation
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Wetting sub-nanochannels via ionic hydration effect for improving charging dynamics
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作者 Yayun Shi Xiaoli Zhao +5 位作者 Qihang Liu Zhenghui Pan Congcong Liu Shanyi Zhu Zhijun Zuo Xiaowei Yang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期473-480,共8页
The ionic transport in sub-nanochannels plays a key role in energy storage,yet suffers from a high energy barrier.Wetting sub-nanochannels is crucial to accelerate ionic transport,but the introduction of water is chal... The ionic transport in sub-nanochannels plays a key role in energy storage,yet suffers from a high energy barrier.Wetting sub-nanochannels is crucial to accelerate ionic transport,but the introduction of water is challenging because of the hydrophobic extreme confinement.We propose wetting the channels by the exothermic hydration process of pre-intercalated ions,the effect of which varies distinctly with different ionic hydration structures and energies.Compared to the failed pre-intercalation of SO_(4)^(2-),HSO_(4)^(-) with weak hydration energy results in a marginal effect on the HOMO(Highest Occupied Molecular Orbital)level of water to avoid water splitting during the electrochemical intercalation.Meanwhile,the ability of water introduction is reserved by the initial incomplete dissociation state of HSO_(4)^(-),so the consequent exothermic reionization and hydration processes of the intercalated HSO_(4)^(-) promote the water introduction into sub-nanochannels,finally forming the stable confined water through hydrogen bonding with functional groups.The wetted channels exhibit a significantly enhanced ionic diffusion coef-ficient by~9.4 times. 展开更多
关键词 Sub-nanochannels Ionic hydration Ionic transport SUPERCAPACITORS Confined water
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Synthesis of Polyethylenes with In-Chain Isolated Carbonyls from CO_(2)and Ethylene via a Tandem Photoreduction/Polymerization Protocol
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作者 Fulin Zhou Haojie Dai +1 位作者 Shan Tang Yongfeng Zhou 《CCS Chemistry》 CSCD 2024年第6期1591-1599,共9页
Aiming at accessing polyethylene-bearing in-chain degradable functionality,copolymerization of carbon dioxide(CO_(2))with ethylene has long been recognized as a significant but highly challenging transformation.Nevert... Aiming at accessing polyethylene-bearing in-chain degradable functionality,copolymerization of carbon dioxide(CO_(2))with ethylene has long been recognized as a significant but highly challenging transformation.Nevertheless,most trials have resulted in ethylene homopolymerization because of the endothermic property and high energy barriers of CO_(2)insertion during polymer chain propagation.Here we report an unprecedented tandem reaction protocol for the synthesis of polyethylenes with in-chain carbonyls from CO_(2)and ethylene by the combination of photocatalytic CO_(2)reduction and palladium-catalyzed coordination/insertion polymerization.This protocol provides an easy way to adjust the carbonyl content(from 0.13 to 12 mol%)and insertion selectivity(up to 99%isolated carbonyls)of the polyethylene copolymers,which enables the polymers tomaintain the main properties of highdensity polyethylene and simultaneously endows them with good photodegradability.In addition,besides apolar polyethylene copolymers,polar-functionalized polyethylenes with in-chain isolated carbonyls can also be synthesized from CO_(2),ethylene and a polar monomer using the same protocol.We believe our present work sheds new light on the synthesis of degradable polyethylenes by employing CO_(2)as a green carbonyl source. 展开更多
关键词 carbon dioxide coordination polymerization polyethylene PHOTOREDUCTION PHOTODEGRADATION
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Boosted Electrocatalytic Glucose Oxidation Reaction on Noble-Metal-Free MoO_(3)-Decorated Carbon Nanotubes
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作者 Yu-Long Men Ning Dou +3 位作者 Yiyi Zhao Yan Huang Lei Zhang Peng Liu 《Transactions of Tianjin University》 EI CAS 2024年第1期63-73,共11页
Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell fabrication.Herein,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge proce... Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell fabrication.Herein,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge process to prepare a noblemetal-free MC-60 catalyst containing MoO_(3),Mo_(2)C,and a Mo_(2)C–MoO_(3)interface.In the GOR,MC-60 shows activity as high as 745μA/(mmol/L cm^(2)),considerably higher than those of the Pt/CNT(270μA/(mmol/L cm^(2)))and Au/CNT catalysts(110μA/(mmol/L cm^(2))).In the GOR,the response minimum on MC-60 is as low as 8μmol/L,with a steady-state response time of only 3 s.Moreover,MC-60 has superior stability and anti-interference ability to impurities in the GOR.The better performance of MC-60 in the GOR is attributed to the abundant Mo sites bonding to C and O atoms at the MoO_(3)–Mo_(2)C interface.These Mo sites create active sites for promoting glucose adsorption and oxidation,enhancing MC-60 performance in the GOR.Thus,these results help to fabricate more effi cient noble-metal-free catalysts for the fabrication of glucose-based biofuel cells. 展开更多
关键词 Interface eff ect ELECTROCATALYSIS Molybdenum oxide GLUCOSE Oxidation reaction
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Nanoscale Precise Editing of Multiple Immune Stimulating Ligands on DNA Origami for T Cell Activation and Cell-Based Cancer Immunotherapy
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作者 Lele Sun Fengyun Shen +3 位作者 Zijian Xiong Yu Chao Chunhai Fan Zhuang Liu 《CCS Chemistry》 CSCD 2024年第3期719-732,共14页
The spatial arrangement of activating ligands is known to have great influence on T cell activation.However,independently studying each ligand’s spatial organization parameter that affects T cell activation remains a... The spatial arrangement of activating ligands is known to have great influence on T cell activation.However,independently studying each ligand’s spatial organization parameter that affects T cell activation remains a great challenge.Here,with DNA origami,we precisely organized the CD3ɛantibodies simulating T cell receptor(TCR)ligands and CD28 antibodies simulating co-stimulatory ligands to interrogate the independent role of TCR-ligand spacing and local copy numbers as well as the spacing between TCR ligands and co-stimulatory ligands on T cell activation.We found that T cell activation benefited fromlocally concentrated TCR ligands with a shorter spacing and was maximized by an∼38 nm spacing between TCR ligands and co-stimulatory ligands.The T cell expander constructed based on our findings could efficiently expand CD8+T cells for tumor immunotherapy.Thus,the DNA nanostructurebased ligands’precise arrangement can be a unique tool in studying immune cell activations and cellbased immunotherapies. 展开更多
关键词 DNA origami T cell activation T cell receptor IMMUNE cancer immunotherapy
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Synergistic silver-mediated and palladium-catalyzed nondirected olefination of aryl C–H bond: quick access to multi-substituted aryl olefins
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作者 Jian Yao Lili Shao +1 位作者 Xiaohong Huo Xiaoming Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第3期882-889,共8页
Transition metal-catalyzed olefination of aryl C-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been e... Transition metal-catalyzed olefination of aryl C-H bond is a powerful tool for the synthesis of alkenes. While the Pd-catalyzed oxidative C-H olefination of arenes, also known as Fujiwara-Moritani reaction, has been established as one of the most efficient methods, the substrates are largely limited to terminal olefins with electron-withdrawing group(s). Herein, we report a synergistic silver-mediated and palladium-catalyzed non-directed C-H olefination of arenes with vinyl(pseudo)halides, which offers a complementary strategy to the typical Fujiwara-Moritani reaction. The reactions proceeded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an efficient access to various multi-substituted aryl olefins, including trisubstituted/tetrasubstituted olefins and several complex olefins derived from medicines or natural products. Mechanistic studies indicated a bimetallic Pd/Ag cooperation is operative in the catalysis, i.e., the reaction is initiated by aryl C-H bond cleavage via ligation with phosphine/Ag species, followed by transferring of the aryl moiety to a vinyl palladium intermediate,which is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd complex. This method enables the synthesis of a wide range of challenging multi-substituted vinyl products from simple arenes(directing-group free) in a streamlined and controllable fashion. 展开更多
关键词 direct C–H olefination multi-substituted aryl alkenes bimetallic Pd/Ag cooperation C–H functionalization
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Chinese herbal medicine Ginkgo biloba L.preparations for ischemic stroke:An overview of systematic reviews and meta-analyses
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作者 Tian-tian Meng Ya-ping You +11 位作者 Min Li Jian-bo Guo Xin-bin Song Jing-yi Ding Xiao-long Xie An-qi Li Shang-jin Li Xiang-jun Yin Peng Wang Zhe Wang Bao-liang Wang Qing-yong He 《Journal of Integrative Medicine》 SCIE CAS CSCD 2024年第2期163-179,共17页
Background:Ginkgo biloba L.preparations(GBLPs)are a class of Chinese herbal medicine used in the adjuvant treatment of ischemic stroke(IS).Recently,several systematic reviews(SRs)and meta-analyses(MAs)of GBLPs for IS ... Background:Ginkgo biloba L.preparations(GBLPs)are a class of Chinese herbal medicine used in the adjuvant treatment of ischemic stroke(IS).Recently,several systematic reviews(SRs)and meta-analyses(MAs)of GBLPs for IS have been published.Objective:This overview aims to assess the quality of related SRs and MAs.Search strategy:Pub Med,Embase,Cochrane Library,Web of Science,Chinese Biological Medicine,China National Knowledge Infrastructure,Wanfang,and Chinese Science and Technology Journals databases were searched from their inception to December 31,2022.Inclusion criteria:SRs and MAs of randomized controlled trials(RCTs)that explored the efficacy of GBLPs for patients with IS were included.Data extraction and analysis:Two independent reviewers extracted data and assessed the methodological quality,risk of bias(ROB),reporting quality,and credibility of evidence of the included SRs and MAs using A Measurement Tool to Assess Systematic Reviews 2(AMSTAR 2),Risk of Bias in Systematic Reviews(ROBIS),the Preferred Reporting Items for Systematic Reviews and Meta-analyses(PRISMA),and the Grading of Recommendations Assessment,Development and Evaluation(GRADE),respectively.Additionally,descriptive analysis and data synthesis were conducted.Results:Twenty-nine SRs/MAs involving 119 outcomes were included in this review.The overall methodological quality of all SRs/MAs was critically low based on AMSTAR 2,and 28 had a high ROB based on the ROBIS.According to the PRISMA statement,the reporting items of the included SRs/MAs are relatively complete.The results based on GRADE showed that of the 119 outcomes,8 were rated as moderate quality,24 as low quality,and 87 as very low quality.Based on the data synthesis,GBLPs used in conjunction with conventional treatment were superior to conventional treatment alone for decreasing neurological function scores.Conclusion:GBLPs can be considered a beneficial supplemental therapy for IS.However,because of the low quality of the existing evidence,high-quality RCTs and SRs/MAs are warranted to further evaluate the benefits of GBLPs for treating IS. 展开更多
关键词 STATEMENT synthesis ALONE
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Recent advances in chemical protein synthesis:method developments and biological applications
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作者 Suwei Dong Ji-Shen Zheng +18 位作者 Yiming Li Huan Wang Gong Chen Yongxiang Chen Gemin Fang Jun Guo Chunmao He Honggang Hu Xuechen Li Yanmei Li Zigang Li Man Pan Shan Tang Changlin Tian Ping Wang Bian Wu Chuanliu Wu Junfeng Zhao Lei Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第4期1060-1096,共37页
The central dogma of modern biology underscores the pivotal roles proteins play in diverse biological processes,the study of which necessitates advanced methods to produce proteins with precision and versatility.Chemi... The central dogma of modern biology underscores the pivotal roles proteins play in diverse biological processes,the study of which necessitates advanced methods to produce proteins with precision and versatility.Chemical protein synthesis,a powerful approach utilizing chemical reactions for the de novo construction of structurally accurate proteins,has emerged as a transformative tool for studying proteins and generating protein derivatives/mimics inaccessible by natural biological machinery,including post-translationally modified proteins,proteins comprised of unnatural amino acids,as well as mirror-image proteins.This review summarizes recent strides in synthetic method developments for chemical protein synthesis,including innovative techniques in solid-phase peptide synthesis,the challenges presented by difficult sequences in either synthesis or folding and the exploration of novel ligation reactions using both chemical and enzymatic methods.Furthermore,the review also delves into newly developed protocols for site-selective protein modifications and the generation of stapled or macrocyclized peptides/miniproteins,highlighting the power of chemical methods to make structurally diverse proteins.Recent applications of synthetic proteins in investigating post-translational modifications(phosphorylation,lipidation,glycosylation,ubiquitination,etc.),mirror-image biological processes and drug development are further discussed.Together,these topics provide a comprehensive overview of the current landscape of chemical protein synthesis. 展开更多
关键词 chemical protein synthesis solid-phase peptide synthesis ligation reactions post-translational modifications mirror-image proteins peptide drugs
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Nanoencapsulation of Lutein with Hydroxypropylmethyl Cellulose Phthalate by Supercritical Anfisolvent 被引量:8
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作者 金鹤阳 夏菲 +2 位作者 江翠兰 赵亚平 何琳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期672-677,共6页
Lutein was nano-encapsuled with hydroxypropylmethyl cellulose phthalate(HPMCP)to maintain its bioactivity and to avoid thermal/light degradation.Supercritical antisolvent precipitation was applied to prepare lutein/HP... Lutein was nano-encapsuled with hydroxypropylmethyl cellulose phthalate(HPMCP)to maintain its bioactivity and to avoid thermal/light degradation.Supercritical antisolvent precipitation was applied to prepare lutein/HPMCP nano-capsule.The effects of several operating parameters on the yield,lutein loading,encapsulation efficiency,particle size and particle size distribution of the nanocapsule were investigated.The mean diameter of nanocapsules ranged from 163nm to 219nm under appropriate experimental conditions.The result of scanning electron microscope showed that the nanocapsules were nearly spherical.The highest yield reached 95.35% when the initial concentration of lutein was saturated.The highest lutein loading of 15.80% and encapsulation efficiency of 88.41% were obtained under the conditions of 11MPa,40℃ and CHPMCP︰Clutein=5︰l.The results may promote the application of lutein in food industry. 展开更多
关键词 羟丙基甲基纤维素 邻苯二甲酸 超临界 叶黄素
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