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Journal of Materials science & Technology 2020年第19期54卷 132-143页

作者： H.liu M.M.Xu s.li Z.B.Bao s.l.zhu F.H.Wang Institute of Metal Research Chinese Academy of SciencesWencui Road 62#Shenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaJinzhai Road 96#Hefei 230026China shenyang National laboratory for Materials science Northeastern UniversityWenhua Road 3#Shenyang 110819China

A low-diffusion Ni Re Pt Al coating((Ni,Pt)Al outer layer in addition to a Re-rich diffusion barrier layer)was prepared on a Ni_(3)Al-base single crystal(sC)superalloy via electroplating and gaseous aluminizing treatments,wherein the electroplating procedures consisted of the composite deposition of Ni-Re followed by electroplating of *** order to perform a comparison with conventional Ni Al and(Ni,Pt)Al coatings,the cyclic oxidation performance of the Ni Re Pt Al coating was evaluated at 1100 and 1150℃.We observed that the oxidation resistance of the Ni Re Pt Al coating was significantly improved by the greater presence of the residualβ-Ni Al phase in the outer layer and the lesser outward-diffusion of Mo from the *** addition,the coating with the Re-rich diffusion barrier demonstrated a lower extent of interdiffusion into the substrate,where the thickness of the second reaction zone(sRZ)in the substrate alloy decreased by 25%.The mechanisms responsible for improving the oxidation resistance and decreasing the extent of sRZ formation are discussed,in which a particular attention is paid to the inhibition of the outward diffusion of Mo by the Re-based diffusion barrier.

关键词： Ni_(3)Al-base superalloy Pt-modified aluminide coating Re-rich diffusion barrier Cyclic oxidation Interdiffusion second reaction zone

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Novel heating-and deformation-induced phase transitions and mechanical properties for multicomponent Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=Fe,Co,Ni,Cu)amorphous alloys

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Journal of Materials science & Technology 2022年第9期104卷 109-118页

作者： J.Ding A.Inoue F.l.Kong s.l.zhu Y.l.Pu E.shalaan A.A.Al-Ghamdi A.l.Greer school of Materials science and Engineering Tianjin UniversityTianjin 300072China International Institute of Green Materials Josai International UniversityTogane 283-8555Japan Institute of Massive Amorphous Alloy science China University of Mining TechnologyXuzhou 221116China Department of Physics King Abdulaziz UniversityJeddah 22254Saudi Arabia MIsis National University of Science and TechnologyMoscow 119049Russia school of Materials science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Department of Materials science and Metallurgy University of CambridgeCambridge CB30FSUK

Multicomponent alloys of Zr_(50)M_(50),Zr_(50)(M,Ag)_(50)and Zr_(50)(M,Pd)_(50)(M=Fe,Co,Ni,Cu)can be melt-spun to obtain amorphous *** maximum thickness for fully amorphous ribbons varies with composition in the range 34-53μ*** contrast,fully amorphous ribbons are not obtainable for binary Zr_(50)Ni_(50)or ternary Zr_(50)(Ni,Cu)_(50)***-induced crystallization occurs through:two stages of amorphous[am]→[~(am')+B2]→[B2+B33]for Zr_(50)M_(50);and[am]→[am'+B2]→[B2+AgZr]for Zr_(50)(M,Ag)_(50);and a single stage of[am]→[B2]for Zr_(50)(M,Pd)_(50),while no B2 phase is formed for the binary and ternary Zr_(50)Q_(50)(Q=Ni or/and Cu)***-spun amorphous ribbons have good bending ***,Zr_(50)M_(50)ribbons in tension show 0.22-0.28%plastic elongation and work-hardening(the yield stress is~820 MPa,the fracture stress is~1200 MPa).When cold-rolled at room temperature to 30%reduction in thickness,Zr_(50)M_(50)ribbons show 10%increase in hardness,while retaining good bending ***-rolling induces precipitation of spheroidal B2 and irregular B33 particles,while deformation in tension induces B2,B33 and also plate-like monoclinic *** B2 and B33 particles form by polymorphic transformation,and include a high density of internal *** novel deformationinduced precipitation has not been recognized for any Zr_(50)Q_(50)binary or ternary *** new multicomponent systems are encouraging for future progress as structural amorphous alloys.

关键词： Multicomponent Microstructure Mechanical properties Phase transition Amorphous alloy

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Temperature Effect on Early Oxidation Behavior of NiCoCrAlY Coatings: Microstructure and Phase Transformation

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Acta Metallurgica sinica(English letters) 2022年第6期35卷 975-984页

作者： A.Ullah A.Khan Z.B.Bao Y.F.Yang M.M.Xu s.l.zhu F.H.Wang University of Chinese Academy of sciences Beijing 100049China shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key laboratory of Green Fabrication and surface Technology of Advanced Metal Materials Ministry of EducationSchool of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243000China Institute of Advanced Wear and Corrosion Resistant and Functional Material Jinan UniversityGuangzhou 510632China shenyang National laboratory for Materials science Northeastern UniversityShenyang 110819China

Initial oxidation behavior of NiCoCrAlY coating prepared by arc-ion plating has been studied in air at 900, 1000 and 1100 ℃. The results showed that phase transformation from transient θ-Al_(2)O_(3) to α-Al_(2)O_(3) was highly related to the temperature and oxidation time. The oxide scale in the initial stage was mainly composed of θ-Al_(2)O_(3) at 900 ℃. Instead, more amount of α-Al_(2)O_(3) emerged out with increasing oxidation temperature. The elemental distribution after oxidation confirmed that faster chromium diffusion to the oxide scale played an important role in the speedy transformation from θ-Al_(2)O_(3) to α-Al_(2)O_(3). Y segregation at scale/coating interface resulted in less cavity formation and hence improved the oxide scale adherence.

关键词： MCrAlY coating Phase transformation Isothermal oxidation Temperature effect

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New insight into the origin and evolution of the flora and fauna of Hainan Island, China

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science China Earth sciences 2025年第1期68卷 52-61页

作者： Hua zhu Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Yunnan International Joint Laboratory of Southeast Asia Biodiversity Conservation Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants

The origin of the biota of Hainan Island, China, remains a fundamental scientific problem. Comparative studies on the biota, geological tectonics, and paleomagnetism proposed that during the Eocene, Hainan Island connected Vietnam and Guangxi, and then moved to the southeast to reach its present location. This review mainly discusses its biota origin from molecular phylogeny and palaeobotanical research. The formation and evolution of the biological groups of Hainan Island were identified via research on their genomes, phylogeny, and molecular biogeography. This research showed that the genera and species that appeared and diverged early in their evolution(i.e., before the Miocene) can be explained by the land connection between Hainan Island, Vietnam, and Guangxi during the Eocene-Oligocene. According to southeast Asian tectonic theory, in the Middle Miocene(at about 15 million years ago), Hainan Island had moved to its present position. The population and genetic divergence of species with late divergence times(after 15 Ma) can be reasonably explained by the close proximity(or land connection) between Hainan Island and the leizhou Peninsula, enabling genetic communication between Hainan Island and the Chinese mainland, but have exceptional cases. Conclusions have been obtained through palaeobotanical studies, showing that in the Eocene-Oligocene period, southwest China and Hainan Island had subtropical vegetation and flora. However, the fossil group in southeast China(in Maoming, near present-day Hainan Island) in the late Eocene indicated a tropical rainforest vegetation and flora. This suggests that in the Paleogene, Hainan Island may have been located near or on the southwest border of Guangxi and northern Vietnam, rather than in its present location. The floristic division of the flora of Hainan Island basically presents a northeast-southwest inclined distribution pattern. This pattern can be explained by the counterclockwise rotation of Hainan Island during i

关键词： Molecular phylogeny Biogeography Paleobotany Origin of flora and fauna Hainan Island of China

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Modification of Maxwell model for conductivity prediction of carbon nanotubes-filled polymer composites with tunneling effect

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 25-36页

作者： Jue zhu longyuan lI Ningtao zhu Zhejiang Provincial Engineering Research Center for the safety of Pressure Vessel and Pipeline Key laboratory of Impact and safety Engineering (Ningbo University) Ministry of Education school of Engineering Computing and Mathematics University of Plymouth Xi'an Zhanshi Testing & Engineering Co.ltd.

Carbon nanotubes(CNTs) have garnered great attention in recent years due to their outstanding electrical, thermal, and mechanical properties. The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity. This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect. In this modified Maxwell model, the CNTs-filled polymer composite is modeled as a three-phase composite, consisting of a matrix(polymer), inclusions(CNTs), and a transition zone(tunneling zone). The effective electrical conductivity(EEC) of the composite is calculated based on the volume fractions and electrical conductivities of the matrix, inclusions, and transition zone. The model's validity is confirmed through the use of available test data, which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites. This study offers valuable insights into the design of high-performance conductive polymer nanocomposites, and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.

关键词： Nanoclay

late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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science China Earth sciences 2025年第1期68卷 297-309页

作者： Wenxing HAO Jin-Hui YANG Guang zhu state Key laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences school of Resource and Environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt(CAOB), adjacent to the North China Craton(NCC) to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age(267–242Ma) and correspond to the Qingfengshan and liujiagou formations. Moreover, two volcanic rock samples have high εHf(t) values(+1.6 to +16.1) and relatively young two-stage Hf model ages(1095–327 Ma), indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC(i.e., the Inner Mongolia Paleo-uplift, IMPU). This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the late Triassic(i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations), indicates the Kulun region experienced an abrupt change in paleogeography during the late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the late Triassic alkaline igneous belt(235–215 Ma) in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleo-uplift

Cyano migration-mediated radical-polar crossover cyclopropanation

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science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu Chen Jie li Chen zhu Key laboratory of Organic synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang Juan li Wei-Hong zhu Zhiqian Guo shanghai Key laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology state Key laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

sequence-activated chemiluminescence(Cl) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated Cl probes involves tailoring highly-controllable Cl signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROs), biothiols or changes in the microenvironment. These unique sequence-activated Cl probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated Cl techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential Cl probes, addressing the technical challenges and discussing the future trajectory by harnessing Cl signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

“One stone, two birds”: salt template enabling porosity engineering and single metal atom coordinating toward high-performance zinc-ion capacitors

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Journal of Energy Chemistry 2025年第1期100卷 637-645页

作者： Chunliu zhu Huanyu liang Ping li Chenglong Qiu Jingyi Wu Jingwei Chen Weiqian Tian Yue zhu Zhi li Huanlei Wang school of Materials science and Engineering Ocean University of China Department of Chemical and Materials Engineering University of Alberta

Zinc-ion hybrid capacitors （ZIHCs） have received increasing attention as energy storage devices owing to their low cost,high safety,and environmental ***,their progress has been hampered by low energy and power density,as well as unsatisfactory long-cycle stability,mainly due to the lack of suitable electrode *** this context,we have developed manganese single atoms implanted in nitrogen-doped porous carbon nanosheets （MnsAs/NCNs） using a metal salt template method as cathodes for *** metal salt serves a dual purpose in the synthesis process:It facilitates the uniform dispersion of Mn atoms within the carbon matrix and acts as an activating agent to create the porous *** applied in ZIHCs,the MnsAs/NCNs electrode demonstrates exceptional performance,including a high capacity of 203 m Ah g-1,an energy density of 138 Wh kg-1at 68 W kg-1,and excellent cycle stability with 91%retention over 10,000 *** calculations indicate that the introduced Mn atoms modulate the local charge distribution of carbon materials,thereby improving the electrochemical *** work demonstrates the significant potential of carbon materials with metal atoms in zinc-ion hybrid capacitors,not only in enhancing electrochemical performance but also in providing new insights and methods for developing high-performance energy storage devices.

关键词： Zinc ion hybrid capacitors Cathodes Carbon materials Heteroatoms single atoms

Nitrogen addition promotes soil carbon accumulation globally

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science China life sciences 2025年第1期68卷 284-293页

作者： Xuemei Yang suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling zhu Chengjun Ji Biao zhu lingli liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key laboratory for Transboundary Ecosecurity of southwest China School of Ecology and Environmental ScienceYunnan University state Key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(sOC) storage, but its effect on sOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how sOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk sOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding sOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of sOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on sOC components for a better understanding of C dynamics in soils.

关键词： meta-analysis nitrogen enrichment soil organic carbon carbon accumulation carbon stability