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Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing Guo Qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China college of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China college of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

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Neural Regeneration Research 2025年第4期20卷 1103-1123页

作者： Xiahong Tang Nan Zheng Qingming Lin Yan You Zheng Gong Yangping Zhuang Jiali Wu Yu Wang Hanlin Huang Jun Ke Feng Chen Shengli Clinical Medical college of Fujian Medical university Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Emergency Fujian Provincial HospitalFuzhouFujian ProvinceChina Fujian Provincial Key Laboratory of Emergency Medicine FuzhouFujian ProvinceChina The Second Department of Intensive Care Unit Fujian Provincial Hospital South BranchFuzhouFujian ProvinceChina

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological *** preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are *** this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB ***,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by *** results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these *** conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

关键词： bone marrow–derived mesenchymal stem cells cardiac arrest cardiac resuscitation hypoxic preconditioning liver isoform of phosphofructokinase mitochondria neuroinflammation oxidative stress pyroptosis reactive oxygen species

Microstructure Evolution and Mechanism of Strength Development of Fly Ash Paste

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Journal of Wuhan university of Technology(Materials Science) 2025年第1期40卷 152-163页

作者： MA Shuzhao WU Shunchuan HUANG Mingqing CHENG Haiyong JIANG Guanzhao NIU Yonghui LIU Zemin SUN Wei Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Zijin School of Ge-ology and Mining Fuzhou UniversityFuzhou 350108China

Three types of activators such as sodium hydroxide,calcium oxide and triethanolamine(TEA)are used to establish different activation environments to address the problems associated with the process of activating fly ash *** conducted mechanical tests and numerical simulations to understand the evolution of microstructure,and used environmental scanning electron microscopy(ESEM)and energy dispersive spectroscopy(EDS)techniques to analyze the microenvironments of the *** mechanical properties of fly ash paste under different activation conditions and the changes in the microstructure and composition were *** results revealed that under conditions of low NaOH content(1%-3%),the strength of the sample increased *** the content exceeded 4%,the rate of increase in strength *** on the results,the optimal NaOH content was identified,which was about 4%.A good activation effect,especially for short-term activation(3-7 d),was achieved using TEA under high doping *** activation effect was poor for long-term strength after 28 *** CaO content did not significantly affect the degree of activation *** maximum effect was exerted when the content of CaO was 2%.The virtual cement and concrete testing laboratory(VCCTL)was used to simulate the hydration process,and the results revealed that the use of the three types of activators accelerated the formation of Ca(OH)_(2) in the *** activators also corroded the surface of the fly ash particles,resulting in a pozzolanic *** active substances in fly ash were released efficiently,and hydration was *** pores were filled with hydration products,and the microstructure changed to form a new frame of paste filling that helped improve the strength of fly ash paste.

关键词： paste filling fly ash activator unconfined compressive strength microstructure hydration simulation

Drosophila models used to simulate human ATP1A1 gene mutations that cause Charcot-Marie-Tooth type 2 disease and refractory seizures

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Neural Regeneration Research 2025年第1期20卷 265-276页

作者： Yao Yuan Lingqi Yu Xudong Zhuang Dongjing Wen Jin He Jingmei Hong Jiayu Xie Shengan Ling Xiaoyue Du Wenfeng Chen Xinrui Wang Institute of Life Sciences College of Biological Science and EngineeringFuzhou UniversityFuzhouFujian ProvinceChina NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate(Fujian Maternity and Child Health Hospital) FuzhouFujian ProvinceChina Medical Research Center Fujian Maternity and Child Health HospitalCollege of Clinical Medicine for Obstetrics&Gynecology and PediatricsFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology and Institute of Neurology of The First Affiliated Hospital Institute of Neuroscienceand Fujian Key Laboratory of Molecular NeurologyFujian Medical UniversityFuzhouFujian ProvinceChina

Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory *** develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause *** located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)*** addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive *** these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut *** found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in *** heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal *** Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.

关键词： ATP1A1 Atpα bang-sensitive paralysis Charcot-Marie-Tooth disease type 2 CRISPR/Cas9 homology-directed repair Na^(+)/K^(+)-ATPase point mutation seizures sodium pump

Recent progress in exploring heterogeneous catalyst surface chemistry with near ambient pressure XPS

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Science China Chemistry 2025年

作者： Yuanjie Xu Zemin An Yu Tang Institute of Molecular Engineering Plus Institute of Molecule Catalysis and In Situ/Operando Studies College of Chemistry Fuzhou University

X-ray photoelectron spectroscopy(XPS) is a crucial surface analysis technique that has become a key tool in the study of heterogeneous catalysis. Detecting surface chemistry under conditions that closely mimic actual industrial catalytic processes is essential for understanding the mechanisms involved. In the past decade, near ambient pressure X-ray photoelectron spectroscopy(NAP-XPS) has been increasingly utilized to study the surface chemistry of catalysts during heterogeneous catalytic processes, offering insights into structure-performance correlations. This review begins with a brief overview of NAP-XPS instrumentation. Next, we discuss the application of NAP-XPS in the study of thermal catalysis reactions, followed by a summary of the research on catalyst restructuring under reaction conditions. Additionally, we address the challenges and future perspectives for the development and application of NAP-XPS. Catalysis is inherently dynamic, requiring an understanding of the real-time behavior of catalysts under varying conditions. Therefore, future improvements in the ability to probe reaction intermediates with higher spatial and temporal resolution under conditions that closely mimic industrial environments are needed.

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Dissipation-free approach for realizing non-Hermitian dynamics in a superconducting circuit

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Yi-Hao Kang Yang Xiao Yu Wang Qi-Ping Su Chui-Ping Yang School of Physics Hangzhou Normal University Fujian Key Laboratory of Quantum Information and Quantum Optics Fuzhou University Department of Physics Fuzhou University

Non-Hermitian dynamics exhibits a wealth of surprising and potentially useful phenomena. However, it is typically realized by coupling a system with thermal reservoirs, which makes the system suffer from thermal fluctuations associated with the dissipation. Here, we propose a dissipation-free approach to realize non-Hermitian dynamics using a superconducting circuit composed of two resonators and a superconducting qutrit. The non-Hermiticity arises in the dynamical matrix for the evolution of the two resonators in the Heisenberg picture, via a photon-number non-conserved dynamics. The energy spectrum of the non-Hermitian dynamical matrix can be retrieved by measuring the state of the two resonators, and a phase transition of the energy spectrum can be observed by varying the control parameters. In the realization of the non-Hermitian dynamics, the dissipation of the system and the post-selection are not required. Thus, the approach is implemented in a deterministic way, and the reservoir-induced noise is suppressed. Numerical simulations indicate that the energy spectrum of the non-Hermitian dynamical matrix obtained via the measurement of the resonators is in accordance with the theoretical prediction. Moreover, we demonstrate the parity discrimination for the state of two four-level qudits as an application, exhibiting the potential of the non-Hermitian dynamics in the field of quantum measurement. This work opens a new avenue for the realization of non-Hermitian dynamics and may have a significant implication in exploring the non-Hermitian phenomena.

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Two New Low Dimensional Lead(Ⅱ) Diiodide Complexes by Introducing Carbonyls on 1,10-Phenanthroline: a Combined Experimental and Theoretical Study

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Chinese Journal of Structural Chemistry 2014年第8期33卷 1164-1170页

作者：吴秀娟陈之荣 college of zhicheng Fuzhou University college of Chemistry Fuzhou University

Two new low dimensional lead（Ⅱ） diiodide complexes with 1,10-phenanthroline- 5,6-dione （Phendione）, PbI2（Phendione）2 （1） and PbI2（Phendione）（DMSO）2 （2）, have been synthesized by solution processes and structurally determined by X-ray diffraction method. Both compounds are mononuclear with the lead centers being in highly distorted octahedral environments. Hydrogen bonds and π-π stacking interactions contribute to the structural extension and stabilization. Theoretical calculations based on the DFT/B3LYP level indicate that the introduction of electronic donating groups on the phenanthroline ring can improve the electron density of nitrogen atoms, and they can replace part of the bridged iodine atoms to lower the structural dimensions. Experimental band gaps of about 2.07 and 1.97 eV indicate their semiconductor nature.

关键词： lead halide phenanthroline derivative DFT calculation

Thermally triggered topological polymerization in diacetylene-functionalized covalent organic framework toward enhanced memristive properties

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Science China Chemistry 2025年

作者： Panke Zhou Yuxing Huang Ziyue Yu Cong Zhang Qian Chen Yiping Li Chao Lin Xiong Chen State Key Laboratory of Photocatalysis on Energy and Environment Key Laboratory of Advanced Carbon-Based Functional MaterialsCollege of Chemistry Fuzhou University

The development of stimuli-responsive switching memory devices and the elucidation of their switching mechanisms in specific environments are crucial for advancing the field of molecular electronics. Herein, we propose two distinct two-dimensional covalent organic frameworks (COFs), namely Py-EDA and Py-BDA, incorporating acetylene (-C≡C-) or diacetylene(-C≡C-C≡C-) moieties, respectively, targeting fabricate memory devices exhibiting stimuli-responsive switching *** findings demonstrate that the incorporation of acetylene units effectively modulates the electronic band structure and enhances the degree ofπ-conjugation, resulting in devices that exhibit typical bipolar nonvolatile memory performance. Notably,upon thermal treatment, the memory behavior of the ITO/Py-BDA/Ag device transitions to a write-once-read-many-times(WORM) mode, displaying decreased SET voltage, increased ON/OFF current ratio, and remarkable retention reliability and cycle stability. This switching behavior is attributed to the occurrence of interlayer solid-state topological polymerization at 350℃, leading to the transformation of diacetylene columnar arrays into enyne chains within Py-BDA, thereby further promoting interlayer charge transfer and separation.

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Synthesis, Structure, and Optical Limiting Properties of an Axial Substituted Bis(8-oxide quinoline)zirconium Phthalocyanine

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Chinese Journal of Structural Chemistry 2018年第12期37卷 1971-1978,1846页

作者： YOU Ming-Hua FANG Xin LIN Mei-Jin college of zhicheng Fuzhou University college of Chemistry Fuzhou University

A novel bis(8-oxide quinoline)zironium phthalocyanine [(OQ)2 Zr Pc] with two 8-oxide quinolone anions at the same axial positions has been successfully synthesized and its chemical structure has been assigned by the 1 H NMR, MS and two-dimensional correlation infrared(2D-IR) spectroscopy as well as by single-crystal X-ray structural analysis. It possessed a moderately effective nonlinear absorption coefficient βeff of 6.69×10-14cm/GW at 532 nm in DMF solution, implying it is a promising candidate for nonlinear optical materials.

关键词： phthalocyanines zirconium complex axial substitution single-crystal structure optical limiting properties