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PHASE TRANSFORmATION AND cHARAcTERISTIcS IN FREcKLE AREAS FOR INcONEL 625 SUPERALLOY

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Acta metallurgica Sinica(English Letters) 2005年第1期18卷 47-54页

作者： J.X.Dong m.c.zhang Y.P.Zeng X.S.Xie UniversityofScienceandTechnologyBeijing Beijing100083China

The freckle formation and their phase characterizatics in freckle areas were investigated by means of microstructure analysis approaches and a thermodynamic equilibrium phase calculation method in an Inconel 625 allay. These results show that in freckle areas a large number of m6c, mc, Laves and δ phases precipitate in grain boundaries even within grain due to the enrichment and segregation of mo and Nb during solidification, which results in almost of these freckle areas covered by these complex precipitated phases and induces small grains in freckle areas. Equilibrium phase and liquid segregation calculation can give a reasonable interpretation of the freckle feature for this alloy.

关键词： freckle superalloy Inconel 625 thermodynamic calculation

cREEP cRAcK GROWTH BEHAVIOR OF ALLOY 718 DURING HIGH TEmPERATURE EXPOSURE

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Acta metallurgica Sinica(English Letters) 2005年第2期18卷 164-172页

作者： J.X.Dong m.c.zhang Y.P.Zeng X.S.Xie DepartmentofmaterialScience UniversityofScienceandTechnologyBeijingBeijing100083China

Alloy 718 is a precipitation strengthened nickel-based superalloy based on the precipitation of γ″-Ni3Nb (DO22 structure) and γ′-Ni3(Al,Ti) (L12 structure) phases. creep crack growth rate (ccGR) was investigated after high temperature exposure at 593, 650 and 677℃ for 2000h in Alloy 718. In addition to the coalescence of γ′/ γ″ and the amount increasing of δ phase, the existence of a bcc chromium enriched α-cr phase was observed by SEm, and the weight fraction of α-cr and other phases were determined by chemical phase analysis methods. The ccGR behavior and regulation have been analyzed by means of strength and structure analysis approaches. The experimental results show higher the exposure temperature and longer the exposure time, lower the ccGR. This is probably attributed to the interaction of material softening and brittling due to complex structure changes during high temperature exposure. Therefore, despite α-cr phase formation and amount enhancement were run in this test range. It seems to us a small amount of α-cr will be not harmful for creep crack propagation resistance, which is critical for disk application in aircraft and land-based gas turbine.

关键词： Alloy 718 creep crack growth rate α-cr phase

FREcKLE FORmATION AND cHARAcTERIZATION OF A Ni-cr-mo-Fe-W ALLOY

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Acta metallurgica Sinica(English Letters) 2004年第4期17卷 414-418页

作者： J.X.Dong m.c.zhang Y.P.Zeng X.S.Xie University of Science and Technology Beijing Beijing 100083 ChinaUniversity of Science and Technology Beijing Beijing 100083 ChinaUniversity of Science and Technology Beijing Beijing 100083 ChinaUniversity of Science and Technology Beijing Beijing 100083 China

The freckle formation and their phase characterization in freckle areas were investigated by means of microstructure analysis approaches and a thermodynamic equilibrium phase calculation method in a Ni-cr-mo-Fe-W alloy. These results show that in freckle areas a large number of m6c, μ and P phases precipitate in grain boundaries even within grain due to the enrichment and segregation of mo and c during solidification, which results in small grains in freckle areas. Equilibrium phase and liquid segregation calculation can give an reasonable interpretation of the freckle feature for this alloy.

关键词： freckle Ni-cr-mo-Fe- W alloy thermodynamic calculation

体素内不相干运动成像的灌注分数是探测和分级crohn's病肠道纤维化的新型生物标志物

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国际医学放射学杂志 2019年第4期 504-504页

作者：吴越 m.c.zhang X.H.Li S.Y.Huang R.mao Z.N.Fang Q.H.cao Department of Radiology The First Affiliated HospitalSun Yat-Sen University

摘要目的 mR体素内不相干运动(IVIm)扩散加权成像可以同时提供灌注和扩散信息,已经被用于评价儿童crohn’s病(cD)活动度和纤维化,然而还没有在成人cD的

关键词：灌注分数 ADc 体素内不相干运动 crohn’s 扩散加权成像纤维化生物标志物

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan zhang Xiaomin cheng Qinghua Guan Jing Dong Bixian chen Lujie Jia Jing zhang Yongzheng zhang Yunjian Liu Hongzhen Lin School of materials Science and Engineering Jiangsu University i-Lab & cAS Key Laboratory of Nanophotonic materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of materials Science and Engineering Xi'an University of Technology State Key Laboratory of chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZmBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZmBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert J.Thomas m.Brandon Westover can zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Synergistically enhanced ORR and HER performance on co-N-c coupled in-situ generated Ptco intermetallic

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Journal of Energy chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo min Song Lulu An Xiao Huang Qian zhang chenhao zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of material chemistry for Energy conversion and Storage (Huazhong University of Science and Technology) ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of co atomic sites and in-situ generated Ptco intermetallic compounds （Imcs）(o-Ptco@coNc) is proposed through co pre-anchoring and subsequent impregnation-reduction *** loading of co atoms provides a chance for in-situ generating Ptco ordered intermetallic *** remaining co single atoms and Ptco Imcs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt co Imcs and co single atoms,o-Ptco@coNc exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-Ptco@coNc delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled Imcs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

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Journal of Energy chemistry 2025年第1期100卷 385-396页

作者： mingming zhang Hanyu Wu Qi chen Jiaxin Yang Bonan Liu School of mechanical Electronic and Control Engineering Beijing Jiaotong University china University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model

Deciphering the role of ultra-low-loaded rhodium in NiFe-mIL-53 for superior oxygen evolution reaction

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Journal of Energy chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua zhang Kailu Guo Lanyue zhang Gening Du Hao You Junfeng Huang mudong Tu Hua Li Yong Peng Wei Dou cailing Xu State Key Laboratory of Applied Organic chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University college of chemistry and chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-mIL-53 modified with ultra-low rhodium（Rh@NiFe-mIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-mIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-mIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： NiFe-mIL-53 Rh Electrochemical reconstruction catalytic mechanism Oxygen evolution reaction