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Europium anomalies in detrital zircons reveal the crustal thickness evolution of South China in Early Neoproterozoic

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Acta Geochimica 2023年第4期42卷 739-746页

作者： zhi chen Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjingChina

The South China Block(SCB)is formed by the amalgamation of the Yangtze and Cathaysia blocks during the Early Neoproterozoic along the Jiangnan ***,the precise amalgamation time of these two blocks and the location of the united SCB in the Rodinia supercontinent remain highly *** tectonic models have been proposed and they may have different implications for the crustal thickness evolution of the central SCB in Early *** evaluate these models,this paper uses a recently calibrated Eu/Eu*-inzircon proxy to reconstruct crustal thickness evolution of the central SCB during Early Neoproterozoic.I compiled and screened U–Pb ages and trace elements of 900–700 Ma detrital zircons from the central SCB and then calculated the zircon Eu/Eu**** age-binned average zircon Eu/Eu*displays a decreasing trend from 870 to 790 Ma,and thus indicates no significant crustal thickening event occurred during this time *** finding seems to be inconsistent with tectonic models that the Yangtze and Cathaysia blocks amalgamated during this time ***,given that available coupled detrital zircon U–Pb and trace element datasets are very limited,additional studies are warranted to further evaluate this hypothesis.

关键词： South China Crustal thickness Neoproterozoic Detrital zircon Eu anomalies

Effect of strain-induced precipitation on microstructure and properties of titanium micro-alloyed steels

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Journal of Iron and Steel Research International 2022年第6期29卷 983-993页

作者： Xiang-dong Huo zhi-wei Lv chen Ao Lie-jun Li Ji-nian Xia Song-jun chen School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640GuangdongChina Iron and Steel Research Institute Shandong Iron and Steel Group Rizhao Co.Ltd.Rizhao 276826ShandongChina

The strain-induced precipitation behavior of titanium micro-alloyed steel was examined through the stress relaxation *** addition,the relationship between strain-induced precipitation and isothermal precipitation was *** findings revealed that the strain-induced precipitation and recrystallization processes of titanium micro-alloyed steel coexist and compete at the same *** results also showed that the recrystallization process was inhibited with straininduced ***,a large amount of nano-sized TiC particles precipitated in Ti micro-alloyed ***,the strain-induced precipitated TiC had a size of 10 nm and isothermally precipitated TiC had a size of 3–6 ***,there was a clear competitive relationship between strain-induced precipitation and isothermal *** findings also showed that strain-induced precipitation had an obvious effect on the refinement of austenite although the effect was not obvious on the increase in the yield ***,isothermal treatment was shown to be more advantageous than strain-induced ***,the major increase in the yield strength was mainly attributed to the precipitation strengthening of nano-sized TiC during isothermal precipitation.

关键词： Ti micro-alloyed steel Stress relaxation Nanometer-carbide Strain-induced precipitation Isothermal precipitation

Electronic and topological properties of kagome lattice LaV3Si2

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Tungsten 2023年第3期5卷 317-324页

作者： Xue-Jiao chen Bing-Wen Zhang dong Han zhi-cheng Zhong CAS Key Laboratory of Magnetic Materials Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Fujian Key Laboratory of Functional Marine Sensing Materials Center for Advanced Marine Materials and Smart SensorsCollege of Material and Chemical EngineeringMinjiang UniversityFuzhou 350108China Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchun 130033China China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Topological kagome lattice at the frontier of fundamental physics plays a key role in non-trivial topological quantum ***,we predict and investigate kagome lattice rare-earth vanadium-based quantum material LaV3Si2using density functional theory *** phonon spectrum and crystal transformation show stability of this material,which may be grown by experimental *** fermions,flat bands,and van Hove points as some basic features are presented in band structure and surface ***,symmetry-based compatibility relations support enforced semi-metal for occupied electron numbers with strong Berry *** results suggest that rare-earth vanadium-based RV3Si2can be treated as a new family kagome lattice.

关键词： Vanadium Kagome lattice Rare earth Electronic Dirac points

Quantificational Etching of AAO Template

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Journal of Materials Science & Technology 2007年第3期23卷 427-429页

作者： Guojun SONG dong chen zhi PENG Xilin SHE Jianjiang LI Ping HAN Institute of Polymer Materials Qingdao University Qingdao 266071 China

Ni nanowires were prepared by electrodeposition in porous anodized aluminum oxide （AAO） template from a composite electrolyte solution. Well-ordered Ni nanowire arrays with controllable length were then made by the partial removal of AAO using a mixture of phosphoric acid and chromic acid （6 wt pct H3PO4：1.8 wt pct H3CrO4）. The images of Ni nanowire arrays were studied by scanning electron microscopy （SEM） to determine the relationship between etching time and the length of Ni nanowire arrays. The results indicate that the length of nanowires exposed from the template can be accurately controlled by controlling etching time.

关键词： Nanowire arrays Anodized aluminum oxide (AAO) Controllable etching

Numerical Analysis of Emergency River Restoration Scheme for Qingping Mega Debris Flow

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Journal of Mountain Science 2013年第1期10卷 130-136页

作者： chen Ri-dong LIU Xing-nian HUANG Er GUO zhi-xue State Key Laboratory of Hydroscience and Engineering Tsinghua University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The mega debris flow occurred on August 13 th 2010 in Qingping town,China(hereafter called '8.13' Debris Flow) have done great damage to the local habitants as well as to the re-construction projects in the quake-hit areas,and the channel-fill deposit problem caused by the debris flow was the most ***,it is of high possibility that an even severe deposit problem would reappear and result in worse *** order to maximize risk reduction of this problem,relevant departments of the government established a series of emergency river restoration schemes,for which the numerical analysis is an important procedure to evaluate and determine the optimized *** study presents a numerical analysis by applying a twodimensional debris flow model combined with a relevant water-sediment model to simulate the deposit during the progress of the debris flow,and to calculate and analyze the river flow field under both the present condition and different restoration *** results show that the debris flow model,which takes the confluence of the Wenjia Gully to the main river into account,could simulate the deposit process quite *** the reproduced debris flow from the simulation of the '8.13' Debris Flow,the original river flow path has switched to a relatively lower place just along the right bank with a high speed of near 7m.s-1 after being blocked by the deposit,which is highly *** prevent this hazard,a recommended scheme is derived through inter-comparison of different restoration *** shows that the recommended scheme is able to reduce the water level and as well to regulate the flow *** on the given conditions of the mainstream and the tributary confluence for the simulated '8.13' Debris Flow,when encountering a debris flow with deposit volume less than 0.5 million m3,the river channel can endure a 20-year return flood;however,when the deposit volume increases to 2 million m3,the flood capacity of the river will be

关键词： Flash flood Debris flow River restoration Numerical analysis Finite element method

Effect of coordination restriction on pressure-induced fluorescence evolution

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Chinese Chemical Letters 2024年第12期35卷 561-565页

作者： Ziyou Zhang Te Ji Hongliang dong zhiqiang chen zhi Su Jiangsu Collaborative Innovation Center of Biomedical Functional Materials College of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210046China Center for High Pressure Science and Technology Advanced Research Shanghai 201203China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

The usage of flexible ligands in constructing MOF materials(FL-MOFs)has been widely studied due to its numerous advantages,including the structural diversity,polynuclear MOFs,transmitting magnetic exchanges,enantioselective separation,asymmetric catalysis,***,the field still faces challenges in deeply understanding the effect of ligand configuration on the properties of these ***,we employ a flexible aggregation-induced emission ligand(4,4-((1E,1 E)-anthracene-9,10-diylbis(ethene-2,1-diyl))dibenzoic acid)with great mechanical stability to construct FL-MOFs to lock the ligand configuration to explore the pressure-induced evolution of the ligand with coordination restriction,involving changes in fluorescence and intermolecular ***-situ high-pressure fluorescence,Raman,and FT-IR experiments have revealed that the intermolecular interaction of AIE-Mn-MOF with configuration restriction increased more rapidly than that of free *** discovery offers valuable insights for synthesizing MOF materials with exceptional mechanical stability and significantly advances our understanding of the impact of coordination restriction in FL-MOFs on their response to external stimuli.

关键词： Coordination chemistry High-pressure chemistry FL-MOFs High-pressure photoluminescent Coordination restriction

A novel application of the SAWD-Sabatier-SPE integrated system for CO_2 removal and O_2 regeneration in submarine cabins during prolonged voyages

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1642-1650页

作者： zhi HUANG Zhao-bo chen Nan-qi REN dong-xue HU dong-huan ZHENG Zhen-peng ZHANG State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China School of Materials Science & Chemical Engineering Harbin Engineering University Harbin 150001 China Institute of Environmental Science and Engineering Nanyang Technological University 637723 Singapore

To improve the working and living environment of submarine crews, an integrated system of CO2 removal and O2 regeneration was designed to work under experimental conditions for 50 people in a submarine cabin during prolonged voyages. The integrated system comprises a solid amine water desorption （SAWD） unit for CO2 collection and concentration, a Sabatier reactor for CO2 reduction and a solid polymer electrolyte （SPE） unit for O2 regeneration by electrolysis. The performances of the SAWD-Sabatier-SPE integrated system were investigated. The experimental results from the SAWD unit showed that the average CO2 concentration in the CO2 storage tank was more than 96% and the outlet CO2 concentration was nearly zero in the first 45 min, and less than 1/10 of inlet CO2 after 60 min when input CO2 was 0.5% （1000 L）. About 950 L of CO2 was recovered with a recovery rate of 92%-97%. The output CO2 concentration was less than 0.2%, which showed that the adsorption-desorption performance of this unit was excellent. In the CO2 reduction unit we investigated mainly the start-up and reaction performance of the Sabatier reactor. The start-up time of the Sabatier reactor was 6, 8 and 10 rain when the start-up temperature was 187.3, 179.5 and 168 ℃, respectively. The product water was colorless, transparent, and had a pH of 6.9-7.5, and an electrical conductivity of 80μs/cm. The sum of the concentration of metal ions （Ru^3＋, Al^3＋, Pb^2＋） was 0.028% and that of nonmetal ions （Cl^-, SO4^2-） was 0.05%. In the O2 regeneration unit, the O2 generation rate was 0.48 m^3/d and the quantity was 2400 L, sufficient to meet the submariners＇ basic oxygen demands. These results may be useful as a basis for establishing CO2-1evel limits and O2 regeneration systems in submarines or similar enclosed compartments during prolonged voyages.

关键词： CO2 removal O2 regeneration Solid amine water desorption (SAWD) Sabatier reactor Solid polymer electrolyte (SPE) Submarine

Synthesis of Novel Chiral 7-Amide Substituted-4-androstene-3,17-dione Derivatives

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Chemical Research in Chinese Universities 2011年第4期27卷 604-609页

作者： chen Shao-rui ZHOU Xue-qin LI Wei LIU dong-zhi School of Chemical Engineering and Technology Tianjin University Tianjin 300072 P. R. China College of Science Hebei University of Science and Technology Shijiazhuang 050018 P. R. China

A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives（8αa ＂8αh or 8βa ＂8βh） was synthesized from the important intermediates 5 by N-acylation and acidic *** 5α and 5β were obtained through the reaction sequence including acetalization,allylic oxidation,oximation and *** structures of the target compounds were characterized by MS,1H NMR,13C NMR and HRMS spectra and their stereo configurations were identified through DEPT（distortionless enhancement by polarization transfer）,HMQC（hetero-nuclear multiple quantum coherence） and NOE（nuclear overhauser effect） correlation.

关键词： Androstenedione Allylic oxidation Reduction N-Acylation

Microstructure and homogenization process of as-cast GH4169D alloy for novel turbine disk

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International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 889-900页

作者： Kai chen Shu-yuan Rui Fa Wang Jian-xin dong zhi-hao Yao School of Materials Science and Engineering University of Science and Technology Beijing

To investigate the microstructure, segregation, and suitable homogenization process of as-cast GH4169D alloy, the microstructure, elements segregation, and precipitates of cast GH4169D ingots prepared by vacuum induction melting (VIM) and vacuum arc remelting (VAR) were observed by optical microscopy (OM), scanning electron microscopy, and energy-dispersive X-ray spectroscopy (EDS). According to the residual segregation model and simulation results of DICTRA thermodynamic software, the homogenization temperature and time range were set as 1120–1170°C and 5–20 h, respectively. The experimental results showed that microscopic dendrite and element segregation occurred in the interior of ingots and the main segregation elements were Nb and Ti. In addition, the precipitates were mainly distributed in interdendritic regions and were composed of NbC, Laves,γ′, and δ phases. The homogenization process suggested that the interdendritic detrimental precipitated Laves phase can be eliminated or redissolved after homogenization at 1150°C for 20 h, suggesting it was the most suitable homogenization treatment. Thermal compression test results showed that the GH4169D alloys after homogenization treatment had no cracks and dynamic recrystallization occurred, with recrystallization volume fraction increasing with temperature, indicating a good working plasticity at temperatures from 1050 to 1200°C.

关键词： GH4169D superalloy as-cast microstructure segregation homogenization thermal deformation