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Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu Chen zi-shuo Wu ya.Hui Li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

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Anti-corrosive and highly reversible zinc metal anode enabled by the phenolic resin coating

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Rare Metals 2024年第5期43卷 2115-2124页

作者： ya.Ping Wang ya.Di ya.g Shu-Qi Duan Li Wang Jia-shuo Guo An-Qiang Pan School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Key Laboratory of Special Functional Materials for Ecological Environment and Information(Hebei University of Technology).Ministry of Education Tianjin 300130China Key Laboratory for New Type of Functional Materials in Hebei Province Hebei University of TechnologyTianjin 300130China School of Materials Science and Engineering Central South UniversityChangsha 410083China

Aqueous zinc-ion batteries have attracted much attention due to their high theoretical capacity,low cost high safety,and ***,challenges such as dendrite growth and side reactions severely hinder the electrochemical performance of the Zn anode,leading to low Coulombic efficiency(CE)or even short circuits Herein,phenolic resin(PF)is used as a protective coating on the surface of the zinc metal *** PF layer can greatly improve the corrosion resistance of the Zn electrode in the ***,this artificial electrode/electrolyte interphase also elevates the nucleation barrier and restrains Zn^(2+)2D diffusion,regulating the zinc deposition/dissolution *** a result,PF@Zn symmetric cells exhibit superior performance than that of bare Zn symmetric cells,achieving a stable and dendrite-free cycle of 1400 ***,the carbon nanotube MnO_(2)||PF@Zn(CNT/MnO_(2)||PF@Zn)full cell also delivers a long cycle life with a high-capacity retention of about 180.0 m Ah·g^(-1)after 1400 cycles,far exceeding that of bare Zn *** work provides a facile strategy for achieving a dendrite-free and rechargeable zinc anode.

关键词： Rechargeable aqueous batteries Zn metal anode Phenolic resin Anti-corrosion

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Mechanical performance of 22SiMn2TiB steel welded with lowtransformation- temperature filler wire and stainless steel filler wire

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Journal of Iron and Steel Research International 2024年第4期31卷 967-981页

作者： zi-dong Lin Kai-jie Song Zhen Sun zi-qian Zhu Xue-feng Zhao Constantinos Goulas Wei ya.Xing-hua Yu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Department of Design Production and Management Faculty of Engineering Technology.University of TwenteEnschede 7500 AETheNetherlands Rotterdam Additive Manufacture Fieldlab(RAMLAB) Rotterdam 3089 JWTheNetherlands

TX-80 low-transformation-temperature(LTT)welding wire was used to replace the traditional ER 307Si welding wire to realize the connection of 22SiMn2TiB armor steel in manual overlay *** previously existing issues,such as welding cracks,large welding deformation,and severe welding residual stress,were solved to ensure good strength and ductility *** particular,with the same welding conditions,TX-80 LTT wire eliminates welding *** reduces the welding deformation no matter the base pretreatment of pre-setting angle or no pre-setting *** comparison,it was found that the microstructure at the TX-80 weld is mainly composed of martensite and a small amount of retained *** contrast,the microstructure of the ER 307Si weld consists of a large amount of austenite and a small amount of skeleton-like *** variation trend of residual stress and microhardness from the weld to the base were investigated and compared with the mechanical properties of base *** TX-80 and the ER 307Si tensile samples elongation is 6.76%and 6.01%,while the ultimate tensile strengths are 877 and 667 MPa,*** average impact toughness at room temperature of the ER 307Si weld is 143.9 J/cm^(2),much higher than that of the TX-80 weld,which is only 36.7 J/cm^(2).The relationship between impact and tensile properties with microstructure species and distribution was *** addition,the fracture surface of the tensile and the impact samples was observed and *** dimples,fewer pores,larger radiation zone,and shear lips of TX-80 samples indicate better tensile ductility and worse impact toughness than those of ER 307Si weld.

关键词： Low-transformation-temperature material 22SiMn2TiB steel Welding deformation Residual stress Martensitic transformation Mechanical property

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Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第9期42卷 990-996页

作者： Bin Lu Feng-shuo Bao zi-Wei He Wen-Jing Xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CziPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

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Regulatory factors of Nrf2 in age-related macular degeneration pathogenesis

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1344-1362页

作者： zi-Ling Hu Yu-Xuan Wang zi-Yue Lin Wen-shuo Ren Bo Liu Hui Zhao Qiong Qin Five Year Program of Ophthalmology and Optometry 2019 Beijing Tong Ren HospitalCapital Medical UniversityBeijing 100054China Four Year Program of Traditional Chinese Pharmacy 2020 School of Traditional Chinese MedicineCapital Medical UniversityBeijing 100069China School of Traditional Chinese Medicine Capital Medical UniversityBeijing 100069China Beijing Key Laboratory of TCM Collateral Disease Theory Research Beijing 100069China Five Year Program of Ophthalmology and Optometry 2021 School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China Biochemistry&Molecular Biology School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China

Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual *** evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress of AMD,and the function of anti-oxidant capacity of PRE plays a fundamental physiological *** factor erythroid 2 related factor 2(Nrf2)is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative *** functions of protecting RPE cells against oxidative stress(OS)and ensuing physiological changes,including inflammation,mitochondrial damage and autophagy dysregulation,have already been *** the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD *** the first time,this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis,including proteins and miRNAs,and their underlying molecular mechanisms,which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.

关键词： Nrf2 upstream regulators retinal pigment epithelia age-related macular degeneration oxidative stress

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Illuminating spin-crossover octanuclear metal-organic cages

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Science China Chemistry 2024年第4期67卷 1208-1215页

作者： Zhi-Kun Liu Alyona A.Starikova Yu-Xia Li Ke Sun Meng Yu zi-shuo ya. Jun Tao Key Laboratory of Cluster Science of Ministry of Education School of Chemistry and Chemical EngineeringLiangxiang CampusBeijing Institute of TechnologyBeijing 102488China Institute of Physical and Organic Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

Spin-crossover(SCO)materials that reversibly switch between high-and low-spin states have potential for the storage of spin state-relative information,and have gained much attention incorporating secondary physical properties,such as fluorescence and magneto-optical *** this study,we synthesized three octanuclear metal-organic cages(MOCs)using tetraphenylethylene-based luminophores,aldehydes,and Fe^(Ⅱ)salts,by subcomponent self-assembly approach,namely[Fe1]-[Fe3].By controlling the ligand-field strength and guest encapsulation,we finely tuned their SCO *** them,MOC[Fe2]displayed nearly complete SCO behavior in the solid state,which is rare for high-nuclearity *** also demonstrated the coupling of SCO with fluorescence emission in these MOCs by using isostructural Zn^(Ⅱ)complexes([Zn1]-[Zn3])as control experiments,for the first *** calculations revealed the energy-transfer mechanism between fluorophores and SCOactive centers,which emphasizes the significant contribution of d-d transitions in the interplay between the occurrence of SCO and fluorescence emission.

关键词： metal-organic cages spin crossover fluorescence switching materials DFT calculation

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Isorhamnetin Downregulates MMP2 and MMP9 to Inhibit Development of Rheumatoid Arthritis through SRC/ERK/CREB Pathway

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Chinese Journal of Integrative Medicine 2024年第4期30卷 299-310页

作者： LIU Xiao-rong LI shuo-fu MEI Wen-ya.LIU Xiang-dan ZHOU Ri-bao College of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China Department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).Methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(MMP2)or MMP9 or SRC were transfected to explore their roles in isorhamnetin-mediated RA-FLS ***-FLS viability,migration,and invasion were ***,a collagen-induced arthritis(CIA)rat model was *** were randomly divided to sham,CIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,*** index was calculated and synovial tissue inflammation was determined in CIA *** levels of MMP2,MMP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRC,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(CREB),were detected in RA-FLS and synovial *** docking was also used to analyze the binding of isorhamnetin to *** In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(P<0.05).Isorhamnetin downregulated the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1βin RA-FLS(P<0.05).The overexpression of either MMP2 or MMP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion,as well as the levels of TNF-α,IL-6,and IL-1β(P<0.05).Furthermore,isorhamnetin bound to SRC and reduced the phosphorylation of SRC,ERK,and CREB(P<0.05).SRC overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability,migration and invasion,as well as the negative regulation of MMP2 and MMP9(P<0.05).In in vivo studies,isorhamnetin decreased arthritis index scores(P<0.05)and alleviated synovial *** reduced the levels of MMP2,MMP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRC,ERK,and CRE

关键词： rheumatoid arthritis isorhamnetin SRC/ERK/CREB matrix metalloproteinase

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Structural transformation from Waugh-type to Keggin-type polyoxomolybdate-based crystalline material for photo/electrocatalysis

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Rare Metals 2024年第5期43卷 2241-2250页

作者： Pei-Sen Wang zi-Tong Wang ya.ya.Tan Peng Chen Xue-Cheng Zhang Lu-Nan Zhang Yong-Ge Wei Lu-Bin Ni School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing100191China

An inorganicDorganic hybrid crystalline material(SiMo_(12)O_(40))[Cu(2,2'-bipy)_(2)]_(2)·2H_(2)O(Complex 1,2,2'-bipy=2,2'-bipyridine)was synthesized for the first time by using 2,2'-bipy and transition metal copper to convert Waugh-type polyoxometalate[MnMo_(9)O_(3)_(2)]_(6-)into a Keggin polyoxometalate structure[SiMo_(12)O_(40)]^(4-)under hydrothermal conditions in glass *** crystal tests and a series of characterizations were carried out on Complex *** structure of Complex 1 is composed of[SiMo_(12)O_(40)]^(4-)and[Cu^(Ⅱ)(2,2'-bipy)_(2)]^(2+).The five-coordinated Cu is connected to two 2,2'-bipy through CuDN bonds,forming an approximately square ***,Complex 1 exhibited good photocatalytic performance for methylene blue degradation and electrocatalytic nitrite reduction properties simultaneously.

关键词： Polyoxometalates Inorganic-organic hybrid materials Photocatalytic Electrocatalytic

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Experimental investigation on pyrolysis products and pore structure characteristics of organic-rich shale heated by supercritical carbon dioxide

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Petroleum Science 2024年第4期21卷 2393-2406页

作者： Bai-shuo Liu Chuan-Jin ya. Jia-Long Qi ya.Qian Liu Liang Xu Jing-Xuan Hou State Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) Key Laboratory of Unconventional Oil & Gas Development (China University of Petroleum (East China)) Ministry of Education School of Petroleum Engineering China University of Petroleum (East China)

The efficient pyrolysis and conversion of organic matter in organic-rich shale,as well as the effective recovery of pyrolysis shale oil and gas,play a vital role in alleviating energy *** state of carbon dioxide（CO2） in the pyrolysis environment of shale reservoirs is the supercritical *** unique supercritical fluid properties not only effectively heat organic matter,displace pyrolysis products and change shale pore structure,but also achieve carbon storage to a certain *** samples were made into powder and three sizes of cores,and nitrogen（N2） and supercritical carbon dioxide（ScCO2）pyrolysis experiments were performed at different final pyrolysis *** properties and mineral characteristics of the pyrolysis products were studied based on gas chromatography analysis,Xray diffraction tests,and mass spectrometry ***,the pore structure characteristics at different regions of cores before and after pyrolysis were analyzed using N2adsorption tests to clarify the impact of fracturing degree on the pyrolysis *** results indicate that the optimal pyrolysis temperature of Longkou shale is about 430℃.Compared with N2,the oil yield of ScCO2pyrolysis is *** pyrolysis oil obtained by ScCO2extraction has more intermediate fractions and higher relative molecular *** ScCO2can effectively improve the pore diameter of shale and its effect is better than that of *** micropores are produced in shale after pyrolysis,and the macropores only are generated in ScCO2pyrolysis environments with temperatures greater than 430℃.The pore structure has different development characteristics at different pyrolysis temperatures,which are mainly affected by the pressure holding of volatile matter and products *** to the surface of the core,the pore development effect inside the core is *** the decrease in core size,the pore diameter,specific surface area,and pore volume of cores all increase after pyrolysis.

关键词： Organic-rich shale Supercritical carbon dioxide In-situ pyrolysis Pore structure Core size and region

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Solidification crack characteristics and sensitivity of peritectic steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1668-1679页

作者： ya.qiang Li Jian-hua Liu zi-ming Wang Ying-ying Li ya.g He Xiao-wei Li Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Hebei Special Vehicle Modification Technology Innovation Center Hebei Vocational University of Technology and EngineeringXingtai 054000HebeiChina Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou 213164JiangsuChina

The characteristics and sensitivity of solidification cracks in peritectic steels were investigated using directional solidifi-cation *** cracks were observed in both hypoperitectic steels(12CrlMoV,15CrMo)and hyper-peritectic steel(20CrMo)during solidification at growth velocities of 15,50,and 80 pm/*** the dendritic boundaries,sulphide precipitates were found,promoting crack *** on the statistical analysis of interdendritic cracks in peritectic steels,the area ratio(RA)of interdendritic cracks in a directional solidification structure was proposed to evaluate the crack sensitivity of peritectic ***,the crack sensitivities of peritectic steels(12CrlMoV,15CrMo,and 20CrMo)were tested,evaluated,and compared with the surface crack rates of three types of steels produced from a steel *** results demonstrated that RA was in good agreement with that of the steel plant,and the crack sensitivity of 12CrlMoV steel was the strongest,followed by that of 15CrMo and 20CrMo ***,RA can be used to evaluate the crack sensitivity of peritectic steel.

关键词： Peritectic steel-Directional solidification Growth velocity Dendritic structure Solidification crack Crack sensitivity

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