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Chinese Journal of Polymer Science 2024年第10期42卷 1610-1618,I0016页

作者： Xin-Yu Chen Yu-Bing fu Xue-Ling yan Lan Liu School of Materials Science and Engineering Key Lab of Guangdong Province for High Property and Functional Polymer MaterialsSouth China University of TechnologyGuangzhou510641China

Elastomers with high strength and toughness,excellent self-healing properties,and biocompatibility have broad application prospects in wearable electronics and other fields,but preparing it remains a *** this work,we propose a highly adaptable strategy by introducing the small molecule crosslinking agent of triethanolamine(TEA)to the poly(thioctic acid)(PTA)chains and preparing the PAx Ey elastomers using a simple synthesis *** strategy stabilizes the PTA chains by constructing multiple non-covalent cross-linked dynamic networks,endowing materials with excellent strength and toughness(tensile strength of 288 kPa,toughness of 278.2 kJ/m3),admirable self-healing properties(self-healing efficiency of 121.6%within 7 h at 70℃),and good *** PAx Ey elastomers can also be combined with MWNTs to become flexible strain sensors,which can be used to monitor human joint movements with high sensitivity,repeatable responses,and stability.

关键词： Thioctic acid Ion clusters Multiple dynamic networks Self-healing strengthening flexible strain sensor

Construction of coal pitch-based hA-K grafted poly condensates and their excellent anti-temperature and viscosity-reducing properties

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Petroleum Science 2024年第4期21卷 2806-2816页

作者： Jing Tan Wei Zhang Xiu-Ling yan hao Zhou Sher Bahadar Khan Seitkhan Azat Shi-You yan hao-Jie Ma Xin-Tai Su Xinjiang Key Laboratory of Clean Conversion and high Value Utilization of Biomass Resources College of Chemistry and Chemical Engineering Yili Normal University School of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling South China University of Technology Drilling fluid Branch of CNPC Xibu Drilling Engineering Company Limited Department of Chemistry Faculty of Science King Abdulaziz University PO Box 80203 faculty of Chemistry and Chemical Technology Al-Farabi Kazakh National University Urumchi huatailong Chemical Additives Co. Ltd.

humic acids(hAs) are widely used as filtrate and viscosity reducers in drilling fluids. however, their practical utility is limited due to poor stability in salt resistance and high-temperature resistance. hightemperature coal pitch(CP) is a by-product from coal pyrolysis above 650.C. The substance's molecular structure is characterized by a dense arrangement of aromatic hydrocarbon and alkyl substituents. This unique structure gives it unique chemical properties and excellent drilling performance, surpassing traditional humic acids in drilling operations. Potassium humate is prepared from CP(CP-hA-K) by thermal catalysis. A new type of high-quality humic acid temperature-resistant viscosity-reducer(Graft CP-hA-K polymer) is synthesized with CP-hA-K, hydrolyzed polyacrylonitrile sodium salt(Na-hPAN),urea, formaldehyde, phenol and acrylamide(AAM) as raw materials. The experimental results demonstrate that the most favorable conditions for the catalytic preparation of CP-hA-K are 1 wt% catalyst dosage, 30 wt% KOh dosage, a reaction temperature of 250.C, and a reaction time of 2 h, resulting in a maximum yield of CP-hA-K of 39.58%. The temperature resistance of the Graft CP-hA-K polymer is measured to be 177.39.C, which is 55.39.C higher than that of commercial hA-K. This is due to the abundant presence of amide, hydroxyl, and amine functional groups in the Graft CP-hA-K polymer,which increase the length of the carbon chains, enhance the electrostatic repulsion on the surface of solid particles. After being aged to 120.C for a specified duration, the Graft CP-hA-K polymer demonstrates significantly higher viscosity reduction(42.12%) compared to commercial hA-K(C-hA-K). furthermore,the Graft CP-hA-K polymer can tolerate a high salt concentration of 8000 mg.L-1, measured after the addition of optimum amount of 3 wt% Graft CP-hA-K polymer. The action mechanism of Graft CP-hA-K polymer on high-temperature drilling fluid is that the Graft CP-hA-K polymer can increase the re

关键词： Viscosity breaker heat resistance Base mud Graft CP-hA-K polymer CP Salt resistance

The light and hypoxia induced gene ZmPORB1 determines tocopherol content in the maize kernel

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Science China(Life Sciences) 2024年第3期67卷 435-448页

作者： Nannan Liu Yuanhao Du Shijuan yan Wei Chen Min Deng Shutu Xu hong Wang Wei Zhan Wenjie huang yan Yin Xiaohong yang Qiao Zhao Alisdair R.fernie Jianbing yan National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China hubei hongshan Laboratory Wuhan 430070China Agro-biological Gene Research Center Guangdong Academy of Agricultural SciencesGuangzhou 510640China College of Agronomy Hunan Agricultural UniversityChangsha 410128China College of Agronomy Northwest A&F UniversityXi'an 710000China State Key Laboratory of North China Crop Improvement and Regulation Hebei Sub-center of National Maize Improvement Center of ChinaCollege of AgronomyHebei Agricultural UniversityBaoding 071001China College of Life Sciences South-Central Minzu UniversityWuhan 430070China Plant Science facility of the Institute of Botany Chinese Academy of SciencesBeijing 100093China National Maize Improvement Center of China Beijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100093China Shenzhen Key Laboratory of Synthetic Genomics Guangdong Provincial Key Laboratory of Synthetic GenomicsShenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Max Planck Institute of Molecular Plant Physiology Potsdam-Golm 14476Germany

Tocopherol is an important lipid-soluble antioxidant beneficial for both human health and plant growth. here, we fine mapped a major QTLqVE1 affecting γ-tocopherol content in maize kernel, positionally cloned and confirmed the underlying gene ZmPORB1(por1), as a protochlorophyllide oxidoreductase. A 13.7 kb insertion reduced the tocopherol and chlorophyll content, and the photosynthetic activity by repressing ZmPORB1 expression in embryos of NIL-K22, but did not affect the levels of the tocopherol precursors hGA(homogentisic acid)and PMP(phytyl monophosphate). furthermore, ZmPORB1 is inducible by low oxygen and light, thereby involved in the hypoxia response in developing embryos. Concurrent with natural hypoxia in embryos, the redox state has been changed with NO increasing and h_(2)O_(2) decreasing, which lowered γ-tocopherol content via scavenging reactive nitrogen species. In conclusion, we proposed that the lower lightharvesting chlorophyll content weakened embryo photosynthesis, leading to fewer oxygen supplies and consequently diverse hypoxic responses including an elevated γ-tocopherol consumption. Our findings shed light on the mechanism for fine-tuning endogenous oxygen concentration in the maize embryo through a novel feedback pathway involving the light and low oxygen regulation of ZmPORB1 expression and chlorophyll content.

关键词： maize tocopherol hypoxia photosynthesis ZmPORB1

A novel metal-free porous covalent organic polymer for efficient room-temperature photocatalytic CO2 reduction via dry-reforming of methane

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Green Energy & Environment 2024年第9期9卷 1407-1418页

作者： Sheng-yan Yin Ziyi Li Yingcai hu Xiao Luo Jishan Li College of Chemistry and Chemical Engineering Hunan University Institute of Basic Medicine and Cancer (IBMC) Chinese Academy of Sciences

At room temperature,the conversion of greenhouse gases into valuable chemicals using metal-free catalysts for dry reforming of methane（DRM） is quite promising and ***,we developed a novel covalent organic porous polymer （TPE-COP） with rapid charge separation of the electron–hole pairs for DRM driven by visible light at room temperature,which can efficiently generate syngas （CO and h2）.Both electron donor (tris（4-aminophenyl）amine,TAPA) and acceptor (4,4',4'',4'''-(（1 E,1'E,1''E,1'''E）-(ethene-1,1,2,2-tetrayltetrakis （benzene-4,1-diyl）)tetrakis （ethene-2,1-diyl）)tetrakis (1-（4-formylbenzyl）quinolin-1-ium),TPE-ChO) were existed in TPE-COP,in which the push–pull effect between them promoted the separation of photogenerated electron–hole,thus greatly improving the photocatalytic *** functional theory （DfT） simulation results show that TPE-COP can form charge-separating species under light irradiation,leading to electrons accumulation in TPE-ChO unit and holes in TAPA,and thus efficiently initiating *** 20 h illumination,the photocatalytic results show that the yields reach 1123.6 and 30.8μmol g-1for CO and h2,respectively,which are significantly higher than those of TPE-ChO small *** excellent result is mainly due to the increase of specific surface area,the enhancement of light absorption capacity,and the improvement of photoelectron-generating efficiency after the formation of ***,this work contributes to understanding the advantages of COP materials for photocatalysis and fundamentally pushes metal-free catalysts into the door of DRM field.

关键词： Metal-free Photocatalytic CO 2 reduction Covalent organic polymer Dry-reforming of methane Electron donor and acceptor

Nanocrystalline WSe_(2)excels at high-performance anode for Na storage via a facile one-pot hydrothermal method

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Tungsten 2024年第1期6卷 248-258页

作者： hai-yan Zou Lei fang Gang Yu Dong Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and DevicesCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Changxing County Quality and Technology Supervision and Testing Center Huzhou 313100China

for the next large-scale energy storage systems,sodium-ion batteries(SIBs)with excellent electrochemical performance are ***,the exploration of anode materials with high specific capacity,fascinating cycling stability and rate capability is still *** transition metal dichalcogenides(TMDs),tungsten diselenide(WSe_(2))has been regarded as an effective anode material for SIBs and has been extensively studied,due to high theoretical capacity and unique twodimensional layered ***,nanocrystalline WSe_(2)is prepared by a facile one-pot hydrothermal *** with the micro-scale WSe_(2),benefiting from the high specific surface area of highly ordered nano-flake structures and short ion/electron transport paths,nanocrystalline WSe_(2)shows excellent electrochemical performance in Na *** 1000 cycles at a current density of 2 A·g^(-1),a high specific capacity of 264.4 mA·h·g^(-1)is still *** full cell matched with the Na_(3)V_(2)(PO_(4))_(3) cathode can deliver an excellent reversible specific capacity of 196.5 mA·h·g^(-1)after 100 cycles at 0.5 A·g^(-1).

关键词： Tungsten diselenide Transition metal dichalcogenides hydrothermal Sodium-ion batteries Layered structure

Engineering Ru（N^N）3-modified covalent organic framework for photocatalytic olefin epoxidation

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Science China Chemistry 2024年第11期67卷 3719-3728页

作者： yan-Lin Li Sheng-Li huang Guo-Yu yang Key Laboratory of Cluster Science (Ministry of Education) Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsSchool of Chemistry and Chemical Engineering Beijing Institute of Technology

Photocatalytic olefin oxidation using air as an oxidant is an environmentally friendly method for producing epoxides. Covalent organic frameworks（COfs） have emerged as promising photocatalysts in various organic synthesis reactions. The combination of tri-（2-pyridinal aldehyde）-containing precursor with 4,4’,4’’-（1,3,5-triazine-2,4,6-triyl）trianiline generated（N^N）-I-COf. Via imine-to-quinoline transformation and coordination anchorage of Ru（N^N）3unit, Ru（N^N）3@Q-COf was obtained with improved chemical stability, skeleton conjugation, and novel photochemical characteristics, and demonstrated excellent photocatalytic activity in olefin epoxidation with a wide range of substrates. The presence of h2O played a crucial role in the formation of reactive oxygen species（ROSs）, which in turn influenced the olefin oxidation process. The hydrophilicity of Ru（N^N）3facilitated the approach of h2O and O2to the photogenerated charges, thereby promoting ROSs generation. The lipophilicity of Q-COf allowed for the absorption of olefin substrates, and its nano-channels increased encountering possibility between olefins and ROSs. Consequently, Ru（N^N）3@Q-COf provided an intriguing platform for olefin photooxidation and could be recycled multiple times without any degradation in performance. This report revealed that the conversion of classical ROSs into less potent oxidants with rapid kinetic rates played a crucial role in achieving highly efficient and selective epoxidation of terminal olefins.

关键词： polypyridyl Ru covalent organic framework olefin epoxidation photocatalysis

Unimolecular Reactions of E-Glycolaldehyde Oxide and Its Reactions with One and Two Water Molecules

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Research 2024年第1期2023卷 809-824页

作者： yan Sun Bo Long Donald G.Truhlar Department of Physics Guizhou UniversityGuiyang 550025China College of Materials Science and Engineering Guizhou Minzu UniversityGuiyang 550025China Department of Chemistry Chemical Theory Centerand Supercomputing InstituteUniversity of MinnesotaMinneapolisMN 55455-0431USA

The kinetics of Criegee intermediates are important for atmospheric ***,the quantitative kinetics of Criegee intermediates are still very limited,especially for those with hydroxy ***,we calculate rate constants for the unimolecular reaction of E-glycolaldehyde oxide[E-hydroxyethanal oxide,E-(Ch_(2)Oh)ChOO],for its reactions with h_(2)O and(h_(2)O)_(2),and for the reaction of the E-(Ch_(2)Oh)ChOO…h_(2)O complex with h_(2)*** the highest level of electronic structure,we use W3X-L//CCSD(T)-f12a/cc-pVDZ-f12 for the unimolecular reaction and the reaction with water and W3X-L//Df-CCSD(T)-f12b/jun-cc-pVDZ for the reaction with 2 water *** the dynamics,we use a dual-level strategy that combines conventional transition state theory with the highest level of electronic structure and multistructural canonical variational transition state theory with small-curvature tunneling with a validated density functional for the electronic structure.

关键词： structure kinetics molecular

Predicting submerged vegetation drag with a machine learning-based method

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Journal of hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu hong-wu Tang Sai-yu Yuan Jing yan College of Water Conservancy and hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of hydrologic-Cycle and hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(h^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

hexagonal boron nitride based slippery liquid infused porous surface with anti-corrosion, anti-contaminant and anti-icing properties for protecting magnesium alloy

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Chinese Chemical Letters 2024年第4期35卷 532-538页

作者： Wenhao yan Shuaiya Xue Xuerui Zhao Wei Zhang Jian Li Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China

In an era where the concept of green development is deeply rooted, magnesium(Mg) alloy as a light metal has a long-term development prospect in the process of energy saving, emission reduction and environmental improvement. however, anti-corrosion performance of Mg alloy is poor due to the high chemical activity and low equilibrium potential, which limits the development of Mg alloy ***, three-dimensional mesopore hollow polypyrrole spheres(MhPS) were prepared, and the MhPS was inserted into the middle of the stacked hexagon boron nitride(h-BN) lamellae, which allowed the hBN to be separated forming a further composite with abundant pore structure. Subsequently, the MhPS/hBN-Oh composite was uniformly sprayed on the Mg alloy surface via simple spraying method to form the superhydrophobic surface(ShS). finally, the slippery liquid infused porous surface(SLIPS) was successfully fabricated by applying drops of silicone lubricant on the superhydrophobic coating surface. After a series of characterization and testing, the results showed that the stacking of h-BN lamellae was significantly reduced after h-BN was successfully embedded by MhPS. In addition, the fabricated SLIPS have excellent self-cleaning, mechanical stability, anti-icing and anti-corrosion properties. Therefore, the method of embedding polymer microspheres not only offers a new strategy for h-BN exfoliation, but also the successful prepared SLIPS largely retards the corrosion of Mg alloy while providing new ideas for the development of SLIPS.

关键词： Anti-corrosion Mg alloy hexagon boron nitride Polypyrrole SLIPS

ELABELA-derived peptide ELA13 attenuates kidney fibrosis by inhibiting the Smad and ERK signaling pathways

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 341-353页

作者： Zhibin yan Ying ShI Runling yanG Jijun XUE Caiyun fU Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University Lanzhou 730000China Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences&Research Unit of Peptide ScienceChinese Academy of Medical Sciences2019RU066Lanzhou UniversityLanzhou 730000China

Kidney fibrosis is an inevitable result of various chronic kidney diseases(CKDs)and significantly contributes to end-stage renal ***,there is no specific treatment available for renal ***13(amino acid sequence:RRCMPLhSRVPfP)is a conserved region of ELABELA in all vertebrates;however,its biological activity has been very little *** the present study,we evaluated the therapeutic effect of ELA13 on transforming growth factor-β1(TGf-β1)-treated NRK-52E cells and unilateral ureteral occlusion(UUO)*** results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum,and reduce the expression of fibrosis biomarkers confirmed by Masson staining,immunohistochemistry,real-time polymerase chain reaction(RT-PCR),and western *** biomarkers were increased after UUO and decreased by administration of ***,we found that the levels of essential molecules in the mothers against decapentaplegic(Smad)and extracellular signal-regulated kinase(ERK)pathways were reduced by ELA13 treatment in vivo and in *** conclusion,ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.

关键词： ELA13 Kidney fibrosis Inflammation Smad Extracllular signal-regulated kinase(ERK)