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Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy

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Chinese Journal of Polymer Science 2024年第10期42卷 1525-1535页

作者： Zhen-yu Wang Xiao-kong Liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin University

Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace, defense, and opto-electronics, but polyimides are difficult to be reprocessed and recycled at the end of their service life, resulting in a significant waste of resources. Hence, it is of great significance to develop recyclable polyimides with comparable properties to the commercial products. Herein, we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII) plastic, synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine bonds. The PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial polyimides. The PtM-CR-PII plastic possesses a high Young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa, which also exhibits high thermal stability with a glass transition temperature of≈220°C. Moreover, the PtM-CR-PII plastic exhibits outstanding waterproofness, acid/alkali-resistance, and solvent-resistance, its appearance and mechanical properties can be well maintained after long-term soaking in water, highly concentrated acid and base, and various organic solvents. Furthermore, the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame retardancy. The PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index (LOI) value of 45.5%. Importantly, the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature, allowing easy separation and recovery of both monomers in high purity. The recovered pure monomers can be used to regenerate new PtM-CR-PII plastics, enabling sustainable polymer-monomers-polymer circulation.

关键词： Chemical recyclability Chemical stability Dynamic imine bonds Mechanical properties Polyimides Polyimines

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Glucagon-like peptide-1 receptor agonists:Exploring the mechanisms from glycemic control to treatment of multisystemic diseases

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World Journal of Gastroenterology 2024年第36期30卷 4036-4043页

作者： Mo-Wei kong Yang yu ying Wan yu Gao Chun-Xiang Zhang Department of Cardiology Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina School of Basic Medical Sciences Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Endocrinology The Affiliated Hospital of Chengde Medical CollegeChengde 067000Hebei ProvinceChina Department of Cardiology The Affiliated Hospital of Southwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Key Laboratory of Medical Electrophysiology Ministry of EducationInstitute of Cardiovascular ResearchBasic Medicine Research Innovation Center for Cardiometabolic DiseasesMinistry of EducationNucleic Acid Medicine of Luzhou Key LaboratorySouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina

This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver *** provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this ***-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and *** glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system *** role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin ***,they improve hormonal and metabolic profiles in polycystic ovary *** editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases.

关键词： Glucagon-like peptide-1 receptor agonists Glycemic control Multisystem diseases Mechanism of action Cardiovascular protection Renal disease Bone metabolism Non-alcoholic fatty liver disease Neuroprotection Polycystic ovary syndrome

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Al-modified yolk-shell silica particle-supported NiMo catalysts for ultradeep hydrodesulfurization of dibenzothiophene and 4,6-dimethyldibenzothiophene:Efficient accessibility of active sites and suitable acidity

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Petroleum Science 2024年第1期21卷 654-666页

作者： Ke yu Wei-Min kong Zhen Zhao Ai-Jun Duan Lian kong Xi-Long Wang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034LiaoningChina

Yolk-shell SiO2 particles(YP)with center-radial meso-channels were fabricated through a simple and effective ***-containing YP-supported NiMo catalysts with different Al amounts(NiMo/AYP-x,x=Si/Al molar proportion)were prepared and dibenzothiophene(DBT)and 4,6-dimethyl-dibenzothiophene(4,6-DMDBT)were employed as the probes to evaluate the hydrodesulfurization(HDS)catalytic *** as-prepared AYP-x carriers and corresponding catalysts were characterized by some advanced characterizations to obtain deeper correlations between physicochemical properties and the HDS *** average pore sizes of series AYP-x supports are above 6.0 nm,which favors the mass transfer of organic *** cavity between the yolk and the shell is beneficial for the enrichment of S-containing compounds and the accessibility between reactants and active *** embedded into the silica framework could facilitate the formation of Lewis(L)and Brønsted(B)acid sites and adjust the metal-support interaction(MSI).Among all the as-synthesized catalysts,NiMo/AYP-20 catalyst shows the highest HDS *** improved HDS activity of NiMo/AYP-20 catalyst is attributed to the perfect combination of excellent structural properties of the yolk-shell mesoporous silica,enhanced acidity,moderate MSI,and good accessibility/dispersion of active components.

关键词： Al-containing yolk-shell silica particles Accessibility Acidity Metal-support interaction Hydrodesulfurization

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Integrating remote sensing and 3-PG model to simulate the biomass and carbon stock of Larix olgensis plantation

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Forest Ecosystems 2024年第4期11卷 543-555页

作者： yu Bai Yong Pang Dan kong Key Laboratory of National Forestry and Grassland Administration on Forestry Remote Sensing and Information System Institute of Forest Resource Information

Accurate estimations of biomass and its temporal dynamics are crucial for monitoring the carbon cycle in forest ecosystems and assessing forest carbon sequestration *** studies have shown that integrating process-based models(PBMs)with remote sensing data can enhance simulations from stand to regional scales,significantly improving the ability to simulate forest growth and carbon stock ***,the utilization of PBMs for large-scale simulation of larch carbon storage distribution is still *** this study,we applied the parameterized 3-PG(Physiological Principles Predicting Growth)model across the Mengjiagang Forest Farm(MFF)to make broad-scale predictions of the biomass and carbon stocks of Larix olgensis *** model was used to simulate average diameter at breast height(DBH)and total biomass,which were later validated with a wide range of observation data including sample plot data,forest management inventory data,and airborne laser scanning *** results showed that the 3-PG model had relatively high accuracy for predicting both DBH and total biomass at stand and regional scale,with determination coefficients ranging from 0.78 to *** on the estimation of total biomass,we successfully produced a carbon stock map of the Larix olgensis plantation in MFF with a spatial resolution of 20 m,which helps with relevant management *** findings indicate that the integration of 3-PG model and remote sensing data can well predict the biomass and carbon stock at regional and even larger *** addition,this integration facilitates the evaluation of forest carbon sequestration capacity and the development of forest management plans.

关键词： 3-PG model Larch Biomass Carbon stock ALS

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Which Neighborhoods Have Easier Access to Online Home Delivery Services?A Spatiotemporal Accessibility Analysis in Nanjing,China

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Chinese Geographical Science 2024年第4期34卷 722-738页

作者： kong yu ZHEN Feng ZHANG Shanqi SHEN Lizhen School of Architecture and Urban Planning Nanjing UniversityNanjing 210093China Provincial Engineering Research Center of Smart City Planning and Digital Governance Nanjing 210093China

The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent *** on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of *** study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering *** geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and *** located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal *** study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility.

关键词： online home delivery services(OHDS) spatiotemporal accessibility neighborhoods accessibility differences Nanjing City China

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Deformation and stability of the seawall,considering the strength uncertainty of cement mixing piles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 483-501页

作者： yuansheng yu Lingling LI Xiangmiao kong Chengyuan LI Zhen GUO Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Hainan Institute Zhejiang UniversitySanya572000China Ninghai Highway and Transportation Management Center Ningbo315600China Ninghai Traffic Engineering Construction Management Institute Ningbo315600China

The cement mixing (CM) pile is a common method of improving soft offshore ground. The strength growth of CM piles under complex conditions is affected by many factors, especially the cement and moisture contents, and shows significant uncertainty. To investigate the stochasticity of the early strength of CM piles and its impact on the displacement and stability of a seawall, a series of laboratory tests and numerical analyses were carried out in this study. Vane shear tests were conducted on the cement-solidified soil to determine the relationships between the undrained shear strength s_(u) of the cement soil curing in the seawater and the cement content a_(c), as well as the in situ soil moisture content w. It can be inferred that the 24 h undrained shear strength follows a normal distribution. A numerical model considering the random CM pile strength was established to investigate the deformation of the seawall. Due to the uncertainty of CM pile strength, the displacement of the seawall demonstrates a certain discreteness. The decrease of the mean undrained shear strength of CM piles causes a corresponding increase in the average displacement of the seawall. When the mean strength of CM piles is lower than a certain threshold, there is a risk of instability. Furthermore, the heterogeneity of the strength within an individual CM pile also has an impact on seawall displacement. Attention should be paid to the uncertainty of CM pile strength to control displacement and stability.

关键词： Construction uncertainty Cement mixing(CM)pile Strength of cement soil Seawall stability Random finite element method(RFEM) Monte Carlo simulation(MCS)

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Achieving High Strength and Tensile Ductility in Pure Nickel by Cryorolling with Subsequent Low-Temperature Short-Time Annealing

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Engineering 2024年第2期33卷 190-203页

作者： Zhide Li Hao Gu Kaiguang Luo Charlie kong Hailiang yu Light Alloys Research Institute Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Electron Microscope Unit University of New South WalesSydneyNSW 2052Australia

Ultra fine-grained pure metals and their alloys have high strength and low *** this study,cryorolling under different strains followed by low-temperature short-time annealing was used to fabricate pure nickel sheets combining high strength with good *** results show that,for different cryorolling strains,the uniform elongation was greatly increased without sacrificing the strength after annealing.A yield strength of 607 MPa and a uniform elongation of 11.7%were obtained after annealing at a small cryorolling strain(ε=0.22),while annealing at a large cryorolling strain(ε=1.6)resulted in a yield strength of 990 MPa and a uniform elongation of 6.4%.X-ray diffraction(XRD),transmission electron microscopy(TEM),scanning electron microscopy(SEM),and electron backscattered diffraction(EBSD)were used to characterize the microstructure of the specimens and showed that the high strength could be attributed to strain hardening during cryorolling,with an additional contribution from grain refinement and the formation of dislocation *** high ductility could be attributed to annealing twins and micro-shear bands during stretching,which improved the strain hardening *** results show that the synergistic effect of strength and ductility can be regulated through low-temperature short-time annealing with different cryorolling strains,which provides a new reference for the design of future thermo-mechanical processes.

关键词： Cryorolling Annealing Nickel Strain hardening Ductility

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Kinematic calibration method with high measurement efficiency and robust identification for hybrid machine tools

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Chinese Journal of Aeronautics 2024年第3期37卷 468-482页

作者： Liping WANG Mengyu LI Guang yu Weitao LI Xiangyu kong State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-precision Manufacturing Equipment and Control Beijing 100084China

Geometric error is the main factor affecting the machining accuracy of hybrid machine *** calibration is an effective way to improve the geometric accuracy of hybrid machine *** necessity to measure both position and orientation at each pose,as well as the instability of identification in case of incomplete measurements,severely affects the application of traditional calibration *** this study,a kinematic calibration method with high measurement efficiency and robust identification is proposed to improve the kinematic accuracy of a five-axis hybrid machine ***,the configuration is introduced,and an error model is ***,by investigating the mechanism error characteristics,a measurement scheme that only requires tool centre point position error measurement and one alignment operation is ***,by analysing the effects of unmeasured degrees of freedom(DOFs)on other DOFs,an improved nonlinear least squares method based on virtual measurement values is proposed to achieve stable parameter identification in case of incomplete measurement,without introducing additional ***,the proposed calibration method is verified through simulations and *** proposed method can efficiently accomplish the kinematic calibration of the hybrid machine *** accuracy of the hybrid machine tool is significantly improved after calibration,satisfying actual aerospace machining requirements.

关键词： Hybrid machine tool Calibration Measurement scheme Improved nonlinear least squares method Virtual measurement values

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Inhibition of SLC26A4 regulated by electroacupuncture suppresses the progression of myocardial ischemia-reperfusion injury

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BIOCELL 2024年第4期48卷 665-675页

作者： FEI kong QIyuAN TIAN BINGLIN KUANG LILI SHANG XIAOXIAO ZHANG DONGYANG LI ying kong Department of Endocrinology Heilongjiang University of Chinese MedicineHarbin150040China Department of Cardiology Heilongjiang University of Chinese MedicineHarbin150040China College of Clinical Medicine Heilongjiang University of Chinese MedicineHarbin150040China Department of Nephrology Beijing Hospital of Integrated Traditional Chinese and Western MedicineBeijing100039China College of Acupuncture and Massage Heilongjiang University of Chinese MedicineHarbin150040China Department of Acupuncture Heilongjiang University of Chinese MedicineHarbin150040China

Introduction:Myocardial ischemia-reperfusion(IR)injury has received widespread attention due to its damaging ***(EA)pretreatment has preventive effects on myocardial IR ***26A4 is a Na+independent anion reverse transporter and has not been reported in myocardial IR ***:Toﬁnd potential genes that may be regulated by EA and explore the role of this gene in myocardial IR ***:RNA sequencing and bioinformatics analysis were performed to obtain the differentially expressed genes in the myocardial tissue of IR rats with EA *** infarction size was detected by TTC *** CK,creatinine kinase-myocardial band,Cardiac troponin I,and lactate dehydrogenase levels were determined by *** effect of SLC26A4 on cardiomyocyte apoptosis was explored by TUNEL staining and western *** effects of SLC26A4 on inﬂammation were determined by HE staining,ELISA,and real-time *** effect of SLC26A4 on the NF-κB pathway was determined by western ***:SLC26A4 was up-regulated in IR rats but downregulated in IR rats with EA *** with IR rats,those with SLC26A4 knockdown exhibited improved cardiac function according to decreased myocardial infarction size,reduced serum LDH/CK/CK-MB/cTnI levels,and elevated left ventricular ejection fraction and fractional ***26A4 silencing inhibited myocardial inﬂammation,cell apoptosis,phosphorylation,and nuclear translocation of NF-κB ***:SLC26A4 exhibited promoting effects on myocardial IR injury,while the SLC26A4 knockdown had an inhibitory effect on the NF-κB *** results further unveil the role of SLC26A4 in IR injury.

关键词： Myocardial ischemia Reperfusion SLC26A4 NF-κB pathway

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Analysis of China’s PM_(2.5)and ozone coordinated control strategy based on the observation data from 2015 to 2020

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Journal of Environmental Sciences 2024年第4期138卷 385-394页

作者： Liuwei kong Mengdi Song Xin Li ying Liu Sihua Lu Limin Zeng yuanhang Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

The coordinated control of PM_(2.5)and ozone has become the strategic goal of national air pollution *** the gradual decline in PM_(2.5)concentration and the aggravation of ozone pollution,a better understanding of the coordinated control of PM_(2.5)and ozone is urgently ***,we collected and sorted air pollutant data for 337 cities from 2015 to 2020 to explore the characteristics of PM_(2.5)and ozone pollution based on China’s five major air pollution *** results show that it is necessary to continue to strengthen the emission reduction in PM_(2.5)and ozone precursors,and control NO_(x) and VOCs while promoting a dramatic emission reduction in PM_(2.5).The primary method of curbing ozone pollution is to strengthen the emission control of VOCs,with a long-term strategy of achieving substantial emission reductions in NO_(x),because VOCs and NO_(x) are also precursors to PM_(2.5);hence,their reductions also contribute to the reduction in PM_(2.5).Therefore,the implementation of a multipollutant emission reduction control strategy aimed at the prevention and control of PM_(2.5)and ozone pollution is the only means to realize the coordinated control of PM_(2.5)and ozone.

关键词： PM_(2.5) Ozone Coordinated control Multipollutant reduction

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