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Nano Research 2024年第7期17卷 5914-5921页

作者： Chun-Ying Chen Qi-Jie Mo fu-zhen li.hai-li.song li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

Quasinormal modes and ringdown waveforms of a Frolov black hole

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Communications in Theoretical Physics 2024年第10期76卷 101-107页

作者： Zhijun song Huajie Gong hai-li li Guoyang fu li-Gang Zhu Jian-Pin Wu Center for Gravitation and Cosmology College of Physical Science and Technology Yangzhou University Basic Teaching Department Shenyang Institute of Engineering Department of Physics and Astronomy Shanghai Jiao Tong University

In this paper we investigate scalar perturbation over a Frolov black hole（BH）, which is a regular BH induced by the quantum gravity effect. The quasinormal frequencies of a scalar field always consistently reside in the lower half-plane, and the time-domain evolution of the field demonstrates a decaying behavior, with the late-time tail exhibiting a power-law pattern. These observations collectively suggest the stability of a Frolov BH against scalar ***, our study reveals that the quantum gravity effect leads to slower decay modes. For the case of the angular quantum number l = 0, the oscillation exhibits non-monotonic behavior with the quantum gravity parameter α0. However, once l ≥ 1, the angular quantum number surpasses the influence of the quantum gravity effect.

关键词： black hole Frolov black hole quantum gravity effects quasinormal modes

Polydatin ameliorates hepatic ischemia-reperfusion injury by modulating macrophage polarization

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 25-34页

作者： hai-li Bao Chuan-Zhi Chen Chang-zhen Ren Ke-Yan Sun Hao liu Shao-Hua song Zhi-Ren fu Department of Organ Transplantation Shanghai Changzheng HospitalNavy Military Medical UniversityShanghai 200003China Department of Surgical Oncology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Cardiology Shanghai Changzheng HospitalNaval Military Medical UniversityShanghai 200003China Department of General Surgery Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

Background:Polydatin,a glucoside of resveratrol,has shown protective effects against various ***,little is known about its effect on hepatic ischemia-reperfusion(I/R)*** study aimed to elucidate whether polydatin protects liver against I/R-induced injury and to explore the underlying ***:After gavage feeding polydatin once daily for a week,mice underwent a partial hepatic I/R *** alanine aminotransferase(ALT)/aspartate aminotransferase(AST),hematoxylin-eosin(H&E)and TdT-mediated dUTP nick-end labeling(TUNEL)staining were used to evaluate liver *** severity related to the inflammatory response and reactive oxygen species(ROS)production was also ***,immunofluorescence and Western blotting were used to detect macrophage polarization and the NF-κB signaling pathway in ***:Compared with the I/R group,polydatin pretreatment significantly attenuated I/R-induced liver damage and *** oxidative stress marker(dihydroethidium fluorescence,malondialdehyde,superoxide dismutase and glutathione peroxidase)and I/R related inflammatory cytokines(interleukin1β,interleukin-10 and tumor necrosis factor-α)were significantly suppressed after polydatin *** addition,the result of immunofluorescence indicated that polydatin reduced the polarization of macrophages toward M1 macrophages both in vivo and in *** blotting showed that polydatin inhibited the pro-inflammatory function of RAW264.7 via down-regulating the NF-κB signaling ***:Polydatin protects the liver from I/R injury by remodeling macrophage polarization via NFκB signaling.

关键词： Hepatic ischemia-reperfusion injury Polydatin Macrophage Polarization Inflammation

Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

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China Foundry 2024年第4期21卷 352-359页

作者： zhen Zhang lin-na Feng Jin-he Wang zheng-kun li Hua-meng fu Hong li zheng-wang Zhu hai-feng Zhang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

Innovative coaxial high-temperature thin-film sensor with core-shell structure surpassing traditional multilayer films

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Rare Metals 2024年第8期43卷 3854-3867页

作者： Chao Wu Guo-Chun Chen fu-Xin Zhao Fan lin Ying-Jun Zeng Yan-Zhang fu Yan-song Zhang li-Da Xu Qin-Nan Chen Rui Tang Dao-Heng Sun zhen-Yin hai Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China AECC Shenyang Engine Institute Shenyang 110015China School of Aerospace Engineering Xiamen UniversityXiamen 361005China

High-temperature thin-film sensors(TFSs)often suffer from inadequate tolerance to elevated *** this study,an innovative approach is presented to fabricate in situ integrated TFSs with a core-shell structure on alloy components using coaxial multi-ink printing *** method replaces traditional layerby-layer(LbL) deposition and LbL sintering processes and achieves simplified one-step *** coaxial TFS includes a conductive Pt core for conducting and sensing and a dielectric shell for electrical isolation and high-temperature *** coaxial Pt resistance grid demonstrates excellent high-temperature stability,with a resistance drift rate of only 0.08%·h^(-1) at 800 ℃,significantly lower than traditional Pt *** employing this method,a Pt thin-film strain gauge(TFSG) is fabricated that boasts remarkable high-temperature electromechanical *** effectively addresses the problem of sensitivity degradation experienced by traditional LbL Pt TFSGs when subjected to high *** demonstrate the system integration potential of the technique by printing and verifying the functionality of a long-path thinfilm resistance grid on turbine blades,which can withstand butane flame up to ~1300℃.These results showcase the potential of core-shell structure of the coaxial TFS for high-temperature applications,providing a novel approach to develop high-performance TFS beyond traditional multilayer structure.

关键词： Coaxial printing Core-shell structure Thinfilm strain gauge High-temperature stability

Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 416-429页

作者： YANG zhen fu Yong li Chao CAI Xi GUO Chuan College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Karst Georesources and the Environment Ministry of EducationGuizhou UniversityGuiyang 500025China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China

A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou *** mineral that makes up the polymetallic layer is related to the sedimentary *** analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of *** results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the haishan *** isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional *** sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from ***,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关键词： sedimentary environment black shale polymetallic layer pyrite early Cambrian

Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-Chen song fu-Ying Wu Yi-Qun Jiang Xiu-zhen Wang Hu Zhao li-Xin Chen liu-Ting Zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China Max Planck Institute for Iron Research 40237DuisseldorfGermany School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride(MgH_(2)) in sustainable energy ***,FeCoNiCrTi high-entropy alloy(HEA) nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH_(2) to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on MgH_(2).In contrast to additive-free MgH_(2),the initial desorption temperature of the constructed MgH_(2)-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH_(2)-HEA composite only required one-twentieth time of that consumed by pure MgH_(2) to absorb 5.0 wt% of H_(2) at 225℃.The synergy between the "hydrogen pumping" effect of Mg_2Ni/Mg_2NiH_4 and Mg_2Co/Mg_2CoH_5 couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH_(2) contributed to the enhanced de/hydrogenation performance of the MgH_(2)-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

Ultrasonic vibration enabled under-liquid forming of metallic glasses

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Science Bulletin 2024年第2期69卷 163-166页

作者： Xin li Luyao li Sajad Sohrabi Jia'nan fu zhen li Zhe Chen Rongce Sun Yu Zhang Jinbiao Huang Heting Zhang Jian Zhu Xiangyan Chen Kaikai song Jiang Ma School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China State Key Laboratory of Radio Frequency Heterogeneous Integration College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen 518060China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Research Institute of Shandong University Shenzhen 518057China

Advancements in forming technology offer significant advantages for the manufacturing industry,including enhanced efficiency,energy conservation,and improved material utilization[1].However,traditional additive manufacturing[2],thermoplastic forming[3],and laser cutting[4]encounter challenges when applied in under-liquid environments,mainly due to difficulties in temperature control and heat source provision.

关键词： glasses liquid metallic

Controlling reversible complexation-mediated polymerization(RCMP)via deep eutectic solvents:fast kinetics,narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： Xin fu zhen Lu Shen li zheng-Hong Luo lin-Xi Hou Department of Materials-Oriented Chemical Engineering College of Chemical EngineeringFuzhou UniversityFuzhou 350116China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200030China Chemical Engineering Zhicheng College of Fuzhou UniversityFuzhou 350116China Qingyuan Innovation Laboratory Quanzhou 362801China

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric *** this work,serials of deep eutectic solvents(DES)with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP)for the first time,yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil *** mechanism and elementary reaction of RCMP were explored deeply,revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization ***,the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic *** investigation demonstrated the considerable potential of DES for RCMP,which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent reversible complexation-mediated polymerization intermolecular hydrogen bonding density functional theory elementary reaction steps

Optical edge-to-screw singularity state conversions

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Photonics Research 2024年第8期12卷 1689-1695页

作者： HAOliN liN JUNHUI JIA GUOHUA liU YANWEN HU zhen li zhenQIANG CHEN SHENHE fu Department of Optoelectronic Engineering Jinan UniversityGuangzhou 510632China Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Guangzhou 510632China Guangdong Provincial Engineering Research Center of Crystal and Laser Technology Guangzhou 510632China

Optical singularity states,which significantly affect propagation properties of light in free space or optical medium,can be geometrically classified into screw and edge *** different types of singularity states do not exhibit direct connection,being decoupled from each other in the absence of external *** we demonstrate a novel optical process in which a higher-order edge singularity state initially nested in the propagating Gaussian light field gradually involves into a screw singularity with a new-born topological charge determined by order of the edge *** considered edge state comprises an equal superposition of oppositely charged vortex and antivortex *** theoretically and experimentally realize this edge-to-screw conversion process by introducing intrinsic vortex–antivortex *** also present a geometrical representation for mapping this dynamical process,based on the higher-order orbital Poincaré*** this framework,the edge-to-screw conversion is explained by a mapping of state evolution from the equator to the north or south pole of the Poincaré*** demonstration provides a novel approach for manipulating singularity state by the intrinsic vortex–antivortex *** presented phenomenon can be also generalized to other wave systems such as matter wave,water wave,and acoustic wave.

关键词： interaction Poincaré wave