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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 systems.The 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

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 street.The typical flow features can be captured to study the correlation between fluid fields and sound fields.In 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 analyzed.The 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 studied.The results show that at the angles between 30°–120°and 190°–350°,the fluctuating pressure contributes more to the generation of dipole sounds.The 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

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 discussed.The 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

Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm2Co17-type magnet

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Rare Metals 2024年第4期43卷 1724-1735页

作者： zhuang Liu Hai-Chen Wu Chao-Yue Zhang Chao-Qun Zhu Guo-xin Chen Huan-ming Lu Ren-Jie Chen Aru Yan CISRI & NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences University of Chinese Academy of Sciences Analytical C enter Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences

Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm2Co17-type magnet,which is a key factor limiting the further improvement of magnetic energy product.In this study,we report that nanoscale strip-like ordered micro-domains distributed in1:7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary phase.Long strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering treatment.After solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1:7H（TbCu7-type structure） phase between the separated strip-like ordered micro-domains.This disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the length.Furthermore,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is proposed.Antiphase boundaries enriched in Cu have already existed in the precursor with long strip-like ordered micro-domains.Therefore,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm2Co17-type magnet.Our results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the key factor improving the distribution of cell boundary phase in Sm2Co17-type magnets.

关键词： Sm 2 Co 17 magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure

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

Visible Light-Induced[3+2]Annulation Reaction of Alkenes with Vinyl Azides:Direct Synthesis of Functionalized Pyrroles

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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： ming Yang xin-Yu Wang Jie Wang Yu-Long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye photocatalysts.Broad substrate scope and high functional group tolerance were demonstrated by more than 50 examples.The reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Adaptive security control of time-varying constraints nonlinear cyber-physical systems with false data injection attacks

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Journal of Control and Decision 2024年第1期11卷 50-59页

作者： Yue-ming Wang Yuan-xin Li Department of Science Liaoning University of TechnologyJinzhouPeople’s Republic of China

In this article,an adaptive security control scheme is presented for cyber-physical systems(CPSs)suffering from false data injection(FDI)attacks and time-varying state constraints.Firstly,an adaptive bound estimation mechanism is introduced in the backstepping control design to mitigate the effect of FDI attacks.Secondly,to solve the unknown sign time-varying statefeedback gains aroused by the FDI attacks,a type of Nussbaum function is employed in the adaptive security control.Then,by constructing a barrier Lyapunov function,it can be ensured that all signals of controlled system are bounded and the time-varying state constraints are not transgressed.Finally,the provided simulation examples demonstrate the effectiveness of the proposed controller.

关键词： Neural networks backstepping technology false data injection(FDI)attacks nonlinear cyber-physical systems controls

TuBG1 promotes hepatocellular carcinoma via ATR/P53-apoptosis and cycling pathways

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 195-209页

作者： Yan Zhang Zhen-Zhen Wang An-Qi Han ming-Ya Yang Li-xin Zhu Fa-ming Pan Yong Wang Department of General Surgery The Second Hospital of Anhui Medical UniversityHefei 230601China Department of General Surgery The First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Epidemiology and Biostatistics School of Public HealthAnhui Medical UniversityHefei 230032China The Key Laboratory of Major Autoimmune Diseases Anhui Medical UniversityHefei 230032China

Background:As reported,γ-tubulin(TuBG1)is related to the occurrence and development of various types of malignant tumors.However,its role in hepatocellular cancer(HCC)is not clear.The present study was to investigate the relationship between TuBG1 and clinical parameters and survival in HCC patients.Methods:The correlation between TuBG1 and clinical parameters and survival in HCC patients was ex-plored by bioinformatics analysis.Immunohistochemistry was used for the verification.The molecular function of TuBG1 was measured using colony formation,scratch assay,trans-well assay and flow cytometry.Gene set enrichment analysis(GSEA)was used to pick up the enriched pathways,followed by investigating the target pathways using Western blotting.The tumor-immune system interactions and drug bank database(TISIDB)was used to evaluate TuBG1 and immunity.Based on the TuBG1-related immune genes,a prognostic model was constructed and was further validated internally and externally.Results:The bioinformatic analysis found high expressed TuBG1 in HCC tissue,which was confirmed us-ing immunohistochemistry and Western blotting.After silencing the TuBG1 in HCC cell lines,more G1 arrested cells were found,cell proliferation and invasion were inhibited,and apoptosis was promoted.Furthermore,the silence of TuBG1 increased the expressions of Ataxia-Telangiectasia and Rad-3(ATR),phospho-P38 mitogen-activated protein kinase(P-P38MAPK),phospho-P53(P-P53),B-cell lymphoma-2 associated X protein(Bax),cleaved caspase 3 and P21;decreased the expressions of B-cell lymphoma-2(Bcl-2),cyclin D1,cyclin E2,cyclin-dependent kinase 2(CDK2)and CDK4.The correlation analysis of immunohistochemistry and clinical parameters and survival data revealed that TuBG1 was negatively corre-lated with the overall survival.The constructed immune prognosis model could effectively evaluate the prognosis.Conclusions:The increased expression of TuBG1 in HCC is associated with poor prognosis,which might be involved in the occurrence and development of HCC.

关键词： TuBG1 Hepatocellular carcinoma Apoptosis Cell cycling Immunomodulators

Pulmonary alveolar proteinosis induced by X-linked agammaglobulinemia:A case report

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World Journal of Clinical Cases 2024年第9期12卷 1644-1648页

作者： Ting Zhang ming Li Li Tan xin Li Department of Respiratory Medicine Kunming Children´s HospitalKunming 650228Yunnan ProvinceChina Department of Emergency Kunming Children's HospitalKunming 650228Yunnan ProvinceChina

BACKGROUND Pulmonary alveolar proteinosis(PAP)and X-linked agammaglobulinemia(XLA)are rare diseases in children.Many theories infer that immunodeficiency can induce PAP,but these reports are almost all review articles,and there is little clinical evidence.We report the case of a child with both PAP and XLA.CASE SUMMARY A 4-month-old boy sought medical treatment due to coughing and difficulty in breathing for>2 wk.He had been hospitalized multiple times due to respiratory infections and diarrhea.Chest computed tomography and alveolar lavage fluid showed typical PAP-related manifestations.Genetic testing confirmed that the boy also had XLA.Following total lung alveolar lavage and intravenous immunoglobulin replacement therapy,the boy recovered and was discharged.During the follow-up period,the number of respiratory infections was significantly reduced,and PAP did not recur.CONCLUSION XLA can induce PAP and improving immune function contributes to the prognosis of children with this type of PAP.

关键词： Pulmonary alveolar proteinosis X-linked agammaglobulinemia Children Immunodeficiency Alveolar lavage Case report