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Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren zhuang-zhuang Liang Ming-xin Niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

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MFG-E8 Alleviates Cognitive Impairments Induced by Chronic Cerebral Hypoperfusion by Phagocytosing Myelin Debris and Promoting Remyelination

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Neuroscience Bulletin 2024年第4期40卷 483-499页

作者： Xiaohong Dong Zhi Zhang xin shu Zi zhuang Pinyi Liu Renyuan Liu Shengnan Xia xinyu Bao Yun Xu Yan Chen Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing210008China Department of Neurology Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing210008China Department of Neurology Drum Tower Hospital of Nanjing Medical UniversityNanjing210008China Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjing210008China Jiangsu Provincial Key Discipline of Neurology Nanjing210008China

Chronic cerebral hypoperfusion is one of the pathophysiological mechanisms contributing to cognitive decline by causing white matter *** phagocytosing myelin debris in a timely manner can promote remyelination and contribute to the repair of white ***,milk fat globule-epidermal growth factor-factor 8(MFG-E8),a microglial phagocytosis-related protein,has not been well studied in hypoperfusion-related cognitive *** found that the expression of MFG-E8 was significantly decreased in the brain of mice after bilateral carotid artery stenosis(BCAS).MFG-E8 knockout mice demonstrated more severe BCAS-induced cognitive impairments in the behavioral *** addition,we discovered that the deletion of MFG-E8 aggravated white matter damage and the destruction of myelin microstructure through fluorescent staining and electron ***,MFG-E8 overexpression by AAV improved white matter injury and increased the number of mature oligodendrocytes after ***,in vitro and in vivo experiments showed that MFG-E8 could enhance the phagocytic function of microglia via theαVβ3/αVβ5/Rac1 pathway and IGF-1 production to promote the differentiation of oligodendrocyte progenitor cells into mature ***,we found that MFG-E8 was mainly derived from astrocytes,not *** findings suggest that MFG-E8 is a potential therapeutic target for cognitive impairments following cerebral hypoperfusion.

关键词： White matter injury Cognitive dysfunction MFG-E8 Remyelination Microglial phagocytosis

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Numerical analysis of the correlation between fluid dynamic modes and hydrodynamic noise in flows around a three-dimensional circular cylinder

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Journal of Hydrodynamics 2024年第1期36卷 119-129页

作者： Jia-jia Qin Ming-xin Zou Yuan zhuang De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Wuhan Second Ship Design and Research Institute Wuhan430205China

The flow around a circular cylinder for Re=1000 is characterized by flow separation and Karman vortex *** typical flow features can be captured to study the correlation between fluid fields and sound *** this paper,the three-dimensional circular cylinder is taken as the research object,and the probes of surface fluctuating pressure and far field sound pressure are arranged every 10°.The directional diagram and the coherence of fluctuating pressure and sound pressure are *** relationship between the flow mode and hydrodynamic noise is studied by using dynamic mode decomposition(DMD).The characteristics of the dipole and quadrupole sound source term of a long span cylinder are *** results show that at the angles between 30°–120°and 190°–350°,the fluctuating pressure contributes more to the generation of dipole *** quadrupole sound source shows three-dimensional effects,which is more obvious in a cylinder with large spanwise length.

关键词： Pressure coherence dynamic mode decomposition flow-sound correlation circular cylinder

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Evaluation and Influencing Factors on Particle Agglomeration in RAP

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 60-68页

作者：唐伟李宁 zhuang Yuan ZHAN He YU xin WU Wenxiu DING Gongying College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China Jiangsu Expressway Engineering Maintenance Technology Center Nanjing 211106China Jinhua Highway and Transportation Management Center Jinhua 321000China

Asphalt extraction test and scanning electron microscopy(SEM) were used for analysis of agglomerations of reclaimed asphalt pavement(RAP) particles. In order to quantify the agglomeration degree of RAP, the fineness modulus ratio(FMR) and the percentage loss index(PLI) were proposed. In addition, grey correlation analysis was conducted to discuss the relationship between particle agglomerations and RAP size,asphalt content(AC), and surface area. Two indexes indicate that the agglomeration degree increases in general as the RAP size reduces. This can be attributed to that particles are prone to agglomeration in the case of higher AC. Based on the SEM images and the material composition of RAP, the particle agglomeration in RAP can be classified into weak agglomeration and strong agglomeration. Grey correlation analysis shows that AC is the crucial factor affecting the agglomeration degree and RAP variability. In order to produce consistent and stable reclaimed mixtures, disposal measures of RAP are suggested to lower the AC of RAP.

关键词： RAP particle agglomeration grey correlation analysis asphalt content

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The influences of perforating phase and bedding planes on the fracture deflection in laminated shale

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Petroleum Science 2024年第2期21卷 1221-1230页

作者： Ming-Zhe Gu Mao Sheng Xiao-Ying zhuang xin-Yi Li Gen-Sheng Li National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China College of Petroleum Engineering China University of PetroleumBeijing102249China College of Civil Engineering Tongji UniversityShanghai200092China

The perforating phase leads to complex and diverse hydraulic fracture propagation behaviors in laminated shale formations. In this paper, a 2D high-speed imaging scheme which can capture the interaction between perforating phase and natural shale bedding planes was proposed. The phase field method was used to simulate the same conditions as in the experiment for verification and hydraulic fracture propagation mechanism under the competition of perforating phase and bedding planes was *** results indicate that the bedding planes appear to be no influence on fracture propagation while the perforating phase is perpendicular to the bedding planes, and the fracture propagates along the perforating phase without deflection. When the perforating phase algins with the bedding planes, the fracture initiation pressure reserves the lowest value, and no deflection occurs during fracture propagation. When the perforating phase is the angle 45°, 60°and 75°of bedding planes, the bedding planes begin to play a key role on the fracture deflection. The maximum deflection degree is reached at the perforating phase of75°. Numerical simulation provides evidence that the existence of shale bedding planes is not exactly equivalent to anisotropy for fracture propagation and the difference of mechanical properties between different shale layers is the fundamental reason for fracture deflection. The findings help to understand the intrinsic characteristics of shale and provide a theoretical basis for the optimization design of field perforation parameters.

关键词： Shale Propagation Perforating Bedding Structure

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Metal complexes of bipyridine-functionalized covalent organic frameworks as efficient electrocatalysts for oxygen evolution reaction

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Rare Metals 2024年第7期43卷 3096-3106页

作者： zhuang-zhuang Wu Tian Xia Ying Liang Yong-Peng Li Zhu-Yin Sui Li-Juan Feng Dao-Xiong Wu xin-Long Tian Qi Chen State Key Laboratory of Marine Resource Utilization in South China Sea School of Marine Science and EngineeringHainan UniversityHaikou 570228China School of Chemistry and Chemical Engineering Yantai UniversityZhuhai519041China School of Bioengineering Zhuhai Campus of Zunyi Medical UniversityZhuhai519041China

Electrocatalytic water splitting is considered a clean and practic al method for producing *** this study,COF-Bpy,a bipyridine-functionalized covalent organic framework(COF),was prepared via post-synthetic modification,after which electrocatalysts for the oxygen evolution reactions(OER)were formed through coordination to single-or double-transition metals(Fe,Co,Ni,FeCo,FeNi or CoNi).COF-Bpy@FeNi delivered the best OER performance among the studied electrocatalysts,with an overpotential of 399 mV at 10 mA·cm^(-2)in an alkaline electrolyte(1.0 mol·L^(-1)KOH aqueous).Notably,the electrocatalytic performance of COF-Bpy@FeNi showed slight degradation during durability testing,which is ascribable to its irreversible benzoquinoline structure and strong metal *** expected,COF-Bpy@FeNi exhibited a low overpotential of 347 mV at a turnover frequency(TOF)of 0.1 s^(-1),which suggests that COF-Bpy@FeNi possesses excellent intrinsic electroc atalytic OER ***,density functional theory(DFT)calculations reveal that the Ni site plays a major role,while the Fe site adjusts the electronic structure of the Ni ions,which rationalizes the excellent OER properties of COF-Bpy@*** study not only provides a simple and efficient method for complexing COFs with transition metals,but also offers a novel strategy for designing porous organic polymer electrocatalysts.

关键词： Covalent organic framework Oxygen evolution reactions(OER)electrocatalyst Nickel-iron synergy Water splitting

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Multiscale urban design based on the optimization of the wind and thermal environments:A case study of the core area of Suzhou Science and Technology City

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Frontiers of Architectural Research 2024年第4期13卷 822-841页

作者： Hua Liu xin Zhou xin Ge Dongqing Han Weiren zhuang Ying Tang Xiaohan Shen Architects&Engineers CO. LTD of Southeast UniversityNanjing 210096China School of Architecture Southeast UniversityNanjing 210096China

New methods are need to coordinate the conflicting spatial demands through urban design research and strategies from the perspective of multi-scale urban climate *** integrate windethermal environment with urban design,we propose three scale levels,namely the district-superblock,superblock-block,and block-building levels,and divide the urban design elements into voids and ***,we establish a multiscale methodological framework in which the urban design contents are clarified by each scale,and the information transmitted between scales is obtained to ensure consistent value propositions and strategic *** microclimate shaping of the urban open space is transformed into guiding strategies and quantitative indicators of the spatial form of the solid *** is transmitted between the scales through the windethermal indicators of windward side and the morphological indicators of solid ***,the methodology was applied to the project in the core area of Suzhou Science and Technology City,and the findings preliminarily verify the effectiveness and feasibility of the *** research influences urban climate studies and urban design practice in three ways:1)improving understanding of the correlation between scales;2)facilitating interaction between the two domains;and 3)providing tools for urban design practices.

关键词： Multiscale transmission Windethermal environment optimization Urban design strategy Urban form

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Novel wreck salvaging method using curved rectangular pipe basing method:A case study of"Yangtze River EstuaryⅡ"ancient shipwreck salvage project

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Underground Space 2024年第5期18卷 97-113页

作者： Qianwei zhuang Guofang Gong Dongrong Zhou Chi Zhang xin Huang Xiaodong Zhu Weihao Yuan Deng Li School of Mechanical Engineering Zhejiang UniversityHangzhou 310030China Shanghai Tunnel Engineering Co.Ltd. Shanghai 200137China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China College of Civil Engineering and Architecture Xinjiang UniversityUrumqi 830047China Shanghai Salvage Company Shanghai 200090China

Shipwreck salvage is a risky,time-consuming,and expensive *** there are many sunken ships along coastlines and in the open seas,the salvage process of a sunken ship has rarely been *** integrated salvage of the"Yangtze River EstuaryⅡ"shipwreck used a novel method with 22 closely locked curved rectangular pipes to form a watertight base that wrapped the shipwreck *** basing was lifted out of the water using a powerful crane situated on an engineering *** the first time,the tunneling method was used in a shipwreck salvage project,significantly reducing the disturbance to the shipwreck and its stowage,thereby preserving the original state and integrity of the shipwreck to the greatest *** this study,the basic concepts of the salvage method and process are *** to critical issues in the new salvage method are provided,including jacking force prediction and major considerations for the structural design of the salvage *** design of the salvage system and salvage process of the"Yangtze River EstuaryⅡ"shipwreck are *** monitored jacking force,pipe deformation,and observed water-tightness verified that the proposed method was effective and *** possible application scenarios for the proposed method are presented at the end.

关键词： Pipe jacking Shipwreck salvage Yangtze River EstuaryⅡ Structural design

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Assessing cutter-rock interaction during TBM tunnelling in granite:Large-scale standing rotary cutting tests and 3D DEM simulations

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3595-3615页

作者： xin Huang Miaoyuan Tang shuaifeng Wang Yixin Zhai Qianwei zhuang Chi Zhang Qinghua Lei Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghaiChina College of Civil Engineering and Architecture Xinjiang UniversityUrumqiChina State Key Laboratory of Geotechnical Engineering Ministry of EducationTongji UniversityShanghaiChina China Shipbuilding NDRI Engineering Co. Ltd.ShanghaiChina Shanghai Tunnel Engineering Co. Ltd.ShanghaiChina Shanghai Shield Design and Experimental Research Center Co. Ltd.ShanghaiChina Department of Earth Sciences Uppsala UniversityUppsalaSweden

The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock *** this paper,we conduct a series of largescale standing rotary cutting tests on granite in conjunction with high-fidelity numerical simulations based on a particle-type discrete element method(DEM)to explore the effects of key cutting parameters on the TBM cutter performance and the distribution of cutter-rock contact *** assessment results of cutter performance obtained from the cutting tests and numerical simulations reveal similar dependencies on the key cutting *** specifically,the normal and rolling forces exhibit a positive correlation with penetration but are slightly influenced by the cutting *** contrast,the side force decreases as the cutting radius ***,the side force shows a positive relationship with the penetration for smaller cutting radii but tends to become negative as the cutting radius *** cutter's relative effectiveness in rock breaking is significantly impacted by the penetration but shows little dependency on the cutting ***,an optimal penetration is identified,leading to a low boreability index and specific energy.A combined Hertz-Weibull function is developed to fit the cutter-rock contact stress distribution obtained in DEM simulations,whereby an improved CSM(Colorado School of Mines)model is proposed by replacing the original monotonic cutting force distribution with this combined Hertz-Weibull *** proposed model outperforms the original CSM model as demonstrated by a comparison of the estimated cutting forces with those from the tests/*** findings from this work that advance our understanding of TBM cutter performance have important implications for improving the efficiency and reliability of TBM tunnelling in granite.

关键词： Large-scale standing rotary cutting test Discrete element method(DEM)simulation Cutter-rock interaction Improved CSM(Colorado School of Mines) model Cutting force

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Modification of the CuO electronic structure for enhanced selective electrochemical CO_(2) reduction to ethylene

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Nano Research 2024年第8期17卷 7194-7202页

作者： xin Wu zhuang Tong Yunliang Liu Yaxi Li Yuanyuan Cheng Jingwen Yu Peng Cao Chunqiang zhuang Qiuzhong Shi Naiyun Liu Xiang Liu Hongyu Liang Haitao Li Institute for Energy Research School of Energy and Power EngineeringJiangsu UniversityZhenjiang 212013China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Institute of Medicine&Chemical Engineering Zhenjiang CollegeZhenjiang 212013China Institute of Advanced Manufacturing and Modern Equipment Technology School of Mechanical EngineeringJiangsu UniversityZhenjiang 212013China

Electrochemical carbon dioxide reduction reaction(CO_(2)RR)can produce value-added hydrocarbons from renewable electricity,providing a sustainable and promising approach to meet dual-carbon targets and alleviate the energy ***,it is still challenging to improve the selectivity and stability of the products,especially the C^(2+) *** we propose to modulate the electronic structure of copper oxide(CuO)through lattice strain construction by zinc(Zn)doping to improve the selectivity of the catalyst to *** performance and in situ characterization analyses show that the compressive strain generated within the CuO lattice and the electronic structure modulation by Zn doping enhances the adsorption of the key intermediate*CO,thereby increasing the intrinsic activity of CO_(2)RR and inhibiting the hydrogen precipitation *** the best catalysts had significantly improved ethylene selectivity of 60.5%and partial current density of 500 mA·cm^(–2),and the highest C^(2+) Faraday efficiency of 71.47%.This paper provides a simple idea to study the modulation of CO_(2)RR properties by heteroatom doped and lattice strain.

关键词： CO_(2) reduction heteroatom-doped lattice strain ethylene selectivity

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