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Chinese Journal of Polymer Science 2024年第10期42卷 1545-1556页

作者： Miao Xie xiao-Rong Wang Zhan-Hua Wang he-sheng xia State Key Laboratory of Polymer Materials Engineering Polymer Research InstituteSichuan University School of Petrochemical Engineering Liaoning Petrochemical University

Covalent adaptive networks (CANs) are capable of undergoing segment rearrangement after being heated, which endows the materials with excellent self-healing and reprocessing performance, providing an efficient solution to the environment pollution caused by the plastic wastes. The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property. In this study, a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups. DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state, confirming excellent dynamic property of the benzopyrazole-urea bonds. As verified by the FTIR results, this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks. Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds. Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds, which also makes the elastomers display excellent creep-resistance performance. This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance.

关键词： Covalent adaptive networks Dynamic covalent bond Self-healing polymer

The ubiquitin codes in cellular stress responses

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Protein & Cell 2024年第3期15卷 157-190页

作者： xiangpeng sheng Zhixiong xia Hanting Yang Ronggui Hu Key Laboratory of Systems health Science of Zhejiang Province School of Life ScienceHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Molecular Biology Shanghai Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai 200031China State Key Laboratory of Animal Disease Control Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069China Department of Neurology State Key Laboratory of Medical NeurobiologyInstitute for Translational Brain ResearchMOE Frontiers Center for Brain ScienceZhongshan HospitalFudan UniversityShanghai 200032China

Ubiquitination/ubiquitylation,one of the most fundamental post-translational modifications,regulates almost every critical cellular process in *** evidence has shown that essential components of numerous biological processes undergo ubiquitination in mammalian cells upon exposure to diverse stresses,from exogenous factors to cellular reactions,causing a dazzling variety of functional *** forms of ubiquitin sig-nals generated by ubiquitylation events in specific milieus,known as ubiquitin codes,constitute an intrinsic part of myriad cellular stress *** ubiquitination events,leading to proteolytic turnover of the substrates or just switch in functionality,initiate,regulate,or supervise multiple cellular stress-associated responses,supporting adaptation,homeostasis recovery,and survival of the stressed *** this review,we attempted to summarize the crucial roles of ubiquitination in response to different environmental and intracellular stresses,while discussing how stresses modulate the ubiquitin *** review also updates the most recent advances in understanding ubiquitination machinery as well as different stress responses and discusses some important questions that may warrant future investigation.

关键词： ubiquitin E3 ligase environmental stresses intercellular stresses stress response homeostasis

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石墨烯/橡胶纳米复合材料研究进展

高分子学报 2014年第6期24卷 715-723页

作者：补强何方方夏和生高分子材料工程国家重点实验室四川大学高分子研究所成都610065

石墨烯结合了碳纳米管导电和黏土片层的结构特征,为发展高性能、多功能聚合物纳米复合材料提供了新的方向.石墨烯/橡胶纳米复合材料近年来引起广泛关注.众多研究结果表明石墨烯是橡胶的理想填料之一,为高性能橡胶改性提供了新途径.本文... 详细信息

石墨烯结合了碳纳米管导电和黏土片层的结构特征,为发展高性能、多功能聚合物纳米复合材料提供了新的方向.石墨烯/橡胶纳米复合材料近年来引起广泛关注.众多研究结果表明石墨烯是橡胶的理想填料之一,为高性能橡胶改性提供了新途径.本文介绍了石墨烯/橡胶纳米复合材料的3种主要制备方法,即乳液共混法、溶液共混法和机械混炼法,以及材料的物理机械性能、电学性能、气体阻隔性能和热学性能,并分析了该类材料的发展前景和存在问题.

关键词：石墨烯橡胶纳米复合材料

Cholic acid mitigates osteoarthritis by inhibiting the NF-κB/PERK/ SIRT1 signaling pathway

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BIOCELL 2024年第7期48卷 1095-1104页

作者： JIAOE sheng ZUMIN YI SANSHAN he QINGCHAO WU xia HUANG GUOQING YAN YUFANG DAI LINCHONG SU The Minda Hospital of Hubei Minzu University Hubei Provincial Key Laboratory of Occurrence and Intervention of Rheumatic DiseaseEnshi445000China The Obstetrics and Gynecology of Jianshi County Hospital of Traditional Chinese Medicine Enshi445300China

Introduction:Cholic acid(CA)is a natural steroid useful in treating chronic bronchitis and *** the other hand,its potential impact on osteoarthritis(OA)is ***:Using an in vitro and in vivo osteoarthritis model,we sought to assess the chondroprotective properties of ***:We employed the Cell Counting Kit-8 to measure the impact of CA on chondrocyte activity to assess the toxicity of the *** molecular biology experimental techniques were used to investigate potential signaling pathways that CA may use to prevent inﬂammation and give chondrocytes ***,how CA affects the OA model in Sprague-Dawley(SD)rats was ***:CA signiﬁcantly suppressed the up-regulation of the interleukin-1β(IL-1β),cyclooxygenase-2(COX-2),and matrix metalloproteinase 13(MMP-13)and the downregulation of aggrecan and type II collagen A1(COL2A)in chondrocytes treated tumor necrosis factor-alpha(TNF-α).Differentially expressed genes(DEG)enrichment revealed IL-17,TNF,chemokine,cytokine-cytokine receptor,toll-like receptor,and nucleotide oligomerization domain-like receptor were the primary signaling *** enriched DEGs included CXCL6,CCL20,MMP3,CXCL3,CXCL11,CCL5,CXCL10,MMP9,MMP13,and CXCL2;these DEGs are involved in inﬂammatory responses and their expression induced by TNF-αwas reversed by CA *** inhibits p65 nuclear translocation and inhibitory subunit kappa B alpha(IκBα)phosphorylation induced by TNF-α.Furthermore,CA attenuated protein expression of protein kinase RNA-like endoplasmic reticulum kinase(PERK),inositol-requiring transmembrane kinase/endoribonuclease 1α(IRE1α),glucose regulatory protein 78(GRP78),and sirtuin 1(SIRT1),and down-regulation of phosphorylation of AMP-activated protein kinase-α(p-AMPKα)in TNF-α-treated ***:CA signiﬁcantly ameliorated cartilage degradation in the OA rat *** alleviated the inﬂammatory response through the nuclear factor kappa B/PERK/SIRT1 axis and

关键词： Cholic acid Cartilage Inﬂammation RNA sequencing Differentially expressed genes

Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： Chen Yang Qiao-sheng xia Cun-Hong Yin Dong-Peng Hua College of Mechanical Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang 550025China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy(PMPEA) exhibits excellent mechanical and tribological ***,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of *** this study,the FeCoNi/Ni_3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics(MD) simulation were *** results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the *** is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces *** particular,the deformation behavior of Ni_3Ti lamellae changes from crystal-like to amorphous-like with decreasing ***,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic(BCC) phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing *** the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch

Two types of coumarins-specific enzymes complete the last missing steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： Yucheng Zhao Yuedong he Liangliang Han Libo Zhang Yuanzheng xia Fucheng Yin xiaobing Wang Deqing Zhao sheng Xu Fei Qiao Yibei xiao Lingyi Kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128China Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacology School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting diverse physiological and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring *** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific *** identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules Coumarins CYP450cyclase

A hybrid physics-informed data-driven neural network for CO_(2) storage in depleted shale reservoirs

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Petroleum Science 2024年第1期21卷 286-301页

作者： Yan-Wei Wang Zhen-Xue Dai Gui-sheng Wang Li Chen Yu-Zhou xia Yu-Hao Zhou College of Construction Engineering Jilin UniversityChangchun130026JilinChina Institute of Intelligent Simulation and Early Warning for Subsurface Environment Jilin UniversityChangchun130026JilinChina School of Energy Resources China University of GeosciencesBeijing100083China Department of Safety Environmental Protection and Quality ManagementShengli OilfieldSinopecDongying257000ShandongChina Key Laboratory of Thermo-Fluid Science and Engineering of MOE School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an710049ShaanxiChina College of Computer Science and Technology China University of Petroleum(East China)Qingdao266580ShandongChina Department of Physics University of FribourgFribourg1700Switzerland

To reduce CO_(2) emissions in response to global climate change,shale reservoirs could be ideal candidates for long-term carbon geo-sequestration involving multi-scale transport ***,most current CO_(2) sequestration models do not adequately consider multiple transport ***,the evaluation of CO_(2) storage processes usually involves laborious and time-consuming numerical simulations unsuitable for practical prediction and *** this paper,an integrated model involving gas diffusion,adsorption,dissolution,slip flow,and Darcy flow is proposed to accurately characterize CO_(2) storage in depleted shale reservoirs,supporting the establishment of a training *** this basis,a hybrid physics-informed data-driven neural network(HPDNN)is developed as a deep learning surrogate for prediction and *** incorporating multiple sources of scientific knowledge,the HPDNN can be configured with limited simulation resources,significantly accelerating the forward and inversion ***,the HPDNN can more intelligently predict injection performance,precisely perform reservoir parameter inversion,and reasonably evaluate the CO_(2) storage capacity under complicated *** validation and test results demonstrate that the HPDNN can ensure high accuracy and strong robustness across an extensive applicability range when dealing with field data with multiple noise *** study has tremendous potential to replace traditional modeling tools for predicting and making decisions about CO_(2) storage projects in depleted shale reservoirs.

关键词： Deep learning Physics-informed data-driven neural network Depleted shale reservoirs CO_(2)storage Transport mechanisms

Hydrogen-rich surface of MoC catalysts for efficient CO_(2) hydrogenation induced by a coupled hydrogen donator

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Nano Research 2024年第8期17卷 7762-7767页

作者： Dong Xu Si-Yuan xia Qi-Yuan Li Jie-sheng Chen Xin-Hao Li School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

Direct CO_(2) hydrogenation offers an important strategy for promoting the global carbon balance,but high thermodynamic and kinetic stability of CO_(2) has restricted its applicability to only a handful of industrial ***,we introduce a proof-of-concept application of the electron-rich Pt surface to promote hydrogen donation for electron-rich MoC particles acting as hydrogen acceptors,thereby constructing hydrogen-rich surface of MoC active ***,the formed hydrogen-rich and electronrich surface could greatly decrease reaction activation energy to boost the efficient CO_(2) hydrogenation into formic acid over the MoC *** optimized MoC@NC/Pt-0.1(NC:nitrogen-doped carbon)catalyst exhibits a high turnover frequency(TOF)value of 1.2 h^(−1) at a lower temperature of 60℃and a TOF of 24.2 h^(−1) under standard reaction conditions widely used in the literature,exceeding 7 times of MoC@NC catalyst and surpassing the benchmark classical non-noble metal active center-based heterogeneous catalyst.

关键词： electron-rich Pt nanoparticles hydrogen donation hydrogen-rich MoC nanoparticles CO_(2) hydrogenation formic acid

Regulated reaction pathway of CO2 photoreduction into CH4 by metal atom pair sites

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Rare Metals 2024年第9期43卷 4620-4627页

作者： Dong-Po he Guang-Bing Huang Jun Hu Yang Wu xiao-Dong Li Qing-xia Chen Shan Zhu Wen-sheng Yan Jun-Fa Zhu Yang Pan Xing-Chen Jiao Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan University hefei National Research Center for Physical Sciences at Microscale National Synchrotron Radiation LaboratoryUniversity of Science and Technology of China Max Planck Institute of Microstructure Physics State Grid Anhui Electric Power Research Institute

The carbon dioxide （CO2） reduction process involves complex protonation, making the resulting product often unpredictable. To achieve the desired product, it is crucial to manipulate the reaction steps. herein, we build the metal atom pair sites for selective CO2photoreduction into methane. As a prototype, Ni atom pair sites loaded on the Mo S2nanosheets were synthesized and verified by highresolution transmission electron microscopy （HRTEM）,X-ray photoelectron spectroscopy （XPS） and X-rayabsorption near edge structure spectra （XANES）. In-situ Fourier transform infrared spectroscopy （FTIR） monitors the*CHO group, a crucial intermediate in CH4production,during CO2photoreduction on the Ni-Mo S2nanosheets,whereas this monitoring is not observed for the Mo S2nanosheets. Also, theoretical calculations disclose that over the Ni-Mo S2nanosheet slab, the formation energy of*CHO intermediates is determined to be lower （0.585 e V） than the desorption energy of*CO intermediates for CO production（0.64 e V）, implying the higher selectivity of CH4production. Accordingly, the Ni-Mo S2nanosheets demonstrate a methane formation rate of 27.21μmol·g-1·h-1, coupled with an impressive electron selectivity of 94.2%.

关键词： Nanosheets

Mechanism and control of nonuniform phase transformation of microalloyed dual-phase steel during cooling process after hot rolling

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Journal of Iron and Steel Research International 2024年第2期31卷 428-441页

作者： Wen-quan Sun sheng-yi Yong Tie-heng Yuan Chao Liu San-bao Zhou Rui-chun Guo Meng-xia Tang National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing100083China Strip Production Plant Xichang Steel and Vanadium Corporation of Pangang GroupXichang615000SichuanChina

After cooling in the hot rolling process,the metallographic structure of microalloyed dual-phase steel is nonuniform along the rolling direction,while the thickness fluctuation of microalloyed dual-phase steel with a nonuniform metallographic structure will occur during cold *** mechanism of nonuniform phase transformation of microalloyed dual-phase steels was studied during the cooling process after hot rolling,and the nonuniform phase transformation of microalloyed dual-phase steel was regulated during the cooling process after hot rolling through process ***,the empirical equation of phase transformation temperature was measured by a dilatometer considering thermal ***,the phase field and temperature field of laminar cooling process were calculated to provide initial boundary conditions for the finite element *** that,the coupling finite element model of the temperature phase transformation of the strip steel in coiling transportation process was *** simulation results show that the different thermal contact conditions of the microalloyed dual-phase steel during coil transportation lead to uneven cooling of the coil,which leads to nonuniform transformation of the coil along the rolling *** addition,by prolonging the time interval from coiling to unloading,the phenomenon of nonuniform phase transformation of microalloyed dual-phase steel can be effectively *** simulation results are applied to industrial *** application results show that prolonging the time interval from coiling to unloading can effectively improve the nonuniform phase transformation of microalloyed dual-phase steel in the cooling process after hot rolling.

关键词： Microalloyed dual-phase steel Thickness fluctuation Cooling heat conduction Nonuniform phase transition Finite element method