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Mineral inclusions in zircon domains and geological significance of SHRIMP U-Pb dating for coesite-bearing zircons of paragneiss in Sulu terrane, eastern China

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Science China Earth Sciences 2005年第2期48卷 175-184页

作者： LIU fulai yang Jingsui XU Zhiqin Institute of Geology Chinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China Institute of GeologyChinese Academy of Geological SciencesBeijing100037China

Laser Raman spectroscopy and cathodoluminescence (CL) image reveal that zircons separated from paragneisses in the southwestern Sulu terrane (eastern China) preserve multi-stage mineral assemblages in different zircon domains. In the same paragneiss zircon sample, some zircon grains retain inherited (detrital) cores with abundant low-pressure mineral inclusions of Qtz + Phe + Ap + impurities and Qtz + Phe + impurities. The ultrahigh-pressure (UHP) metamorphic overgrowths mantles of these zircons preserve Coe, Coe + Phe and other UHP mineral inclusions, indicating that these inherited (detrital) zircons from protoliths experienced metamorphic recrystallization during the Sulu UHP metamorphic event. However, other zircon grains preserve UHP mineral inclusions of Coe, Coe + Ap and Coe + Phe in the cores and mantles, whereas the outmost rims contain quartz (Qtz) and other low-pressure mineral inclusions. These phenomena prove that the second group zircons were crystallized at UHP metamorphic stage and overprinted by the late retrogressive metamorphism related to the Sulu terrane exhumation. SHRIMP U-Pb dating reveals that zircons separated from the paragneisses recorded complicated geochronological traces. Some zircons retain inherited cores with the 206Pb/238U ages of 284-754 Ma, indicating the complexity of the detrital zircons in protoliths. Coesite-bearing zircon domains recorded 238-266 Ma (with the average age of 245(14 Ma) for the UHP metamorphic event. The retrogressive rims of zircons recorded 213-223 Ma (with the average age of 217(15 Ma) for the late-stage amphibolite facies metamorphic event, indicating that the rapid exhumation time for the Sulu UHP terrane is about 220 Ma.

关键词： Sulu terrane, paragneiss, zircon, mineral inclusion, cathodoluminescence, SHRIMP U-Pb dating.

An Efficient Prins Cyclization for Stereoselective Synthesis of Tetrahydropyran from Imines and Homoallyl Alcohols

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Chinese Journal of Chemistry 2014年第11期32卷 1095-1098页

作者： Congrong Liu Daojuan Cheng fulai yang School of Environment Engineering Nanjing Institute of TechnologyNanjingJiangsu 211167China Joint Laboratory of Green Synthetic Chemistry Department of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026China

An unprecedented protocol has been developed for the efficient synthesis of substituted tetrahydropyrans via a bismuth-promoted Prins cyclization of imines with homoallyl *** the presence of 40 mol%BiCl_(3),a wide variety of imines react smoothly with homoallyl alcohols at room temperature to give the corresponding 4-chlorotetrahydropyran derivatives in good to excellent yields.

关键词： Prins cyclization tetrahydropyrans imine homoallyl alcohol Lewis acid

Catalytic C-N Bond Alkynylation of N-Benzylic Sulfonamides with Terminal Alkynes

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Chinese Journal of Chemistry 2014年第5期32卷 387-390页

作者： Congrong Liu fulai yang Tingting Wang School of Environment Engineering Nanjing Institute of TechnologyNanjingJiangsu 211167China Department of Chemistry University of Science and Technology of ChinaHefeiAnhui 230026China

A new cross-coupling reaction of N-benzylic sulfonamides with terminal alkynes for the synthesis of internal alkynes is *** the presence of 5 mol%of(Tf)_(2)NH/Bi(OTf)_(3)(1∶1),a broad range of N-benzylic sulfona-mides react smoothly with arylacetylenes to afford structurally diverse internal alkynes in moderate to excellent *** reasoned that vinyl cations could be formed by the regioselective attack of terminal alkynes with benzyl cations generated in situ from N-benzylic sulfonamides under acidic conditions,which then eliminated to form a carbon-carbon triple bond.

关键词： benzylic amines alkynylation internal alkynes carbon nucleophiles cross-coupling

Magmatic Event at the End of the Archean in Eastern Hebei Province and Its Geological Implication

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Acta Geologica Sinica(English Edition) 2006年第6期80卷 819-833页

作者： GENG Yuansheng LIU fulai yang Chonghui Institute of Geology Chinese Academy of Geological Sciences Beijing 100037

By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ago, the Qingyangshu gabbroic gneiss 2536 Ma, the Yinmahe granodioritic gneiss near Lücao, Lulong County, 2533 Ma, the gabbro-dioritic gneiss near Longwan, Qianxi County, 2518-2515 Ma, the Qiuhuayu trondjemitic gneiss at Zunhua 2515 Ma, the Xiaoguanzhuang tonalitic gneiss at Zunhua 2495 Ma, and the Cuizhangzi gneiss in Qianxi County 2492 Ma. These geochronilogical data demonstrate that, though diverse in composition, type and origin, the granitic gneisses in eastern Hebei Province were emplaced and crystallized in a rather short period of magmatic activity. The formation of such a great amount of gneisses in this small time gap suggests that it was a critical crust accretion stage at the end of Neoarchean. The fact that granitoids of various types occurred at the same time implies a large-scale underplating （mantle plume） activity, which was then responsible for the crust accretion.

关键词： orthogneiss magmatic event Neoarchean zircon age eastern Hebei Province

AZ31镁合金在高周疲劳过程中微观组织和孪晶演变特征

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稀有金属材料与工程 2023年第8期52卷 2693-2701页

作者：杨福来王强张峥北京航空航天大学材料科学与工程学院北京100191 中北大学材料科学与工程学院山西太原030051

利用扫描电子显微镜(SEM)和电子背散射衍射(EBSD)技术研究了室温条件下AZ31镁合金在不同加载频率(3和30 Hz)和不同应力幅值(90,95,100,105,110 MPa)疲劳变形后的组织演变规律及断口形貌特征。结果表明:随着加载应力增加,基体内残余孪晶... 详细信息

利用扫描电子显微镜(SEM)和电子背散射衍射(EBSD)技术研究了室温条件下AZ31镁合金在不同加载频率(3和30 Hz)和不同应力幅值(90,95,100,105,110 MPa)疲劳变形后的组织演变规律及断口形貌特征。结果表明:随着加载应力增加,基体内残余孪晶数量增加,残余孪晶主要以{1012}拉伸孪晶形式存在。随着应力幅值的增加晶粒逐渐细化,这是由于在循环过程中,拉伸孪晶演变诱导晶粒细化。随着应力幅值的增加,织构强度显著减弱,这与试样疲劳后的再结晶机制有关。通过对试样疲劳断口的分析,发现孪晶片层处容易引起裂纹萌生,随着应力的增加,试样中裂纹扩展区面积逐渐减小,在疲劳裂纹扩展区观察到明显的疲劳辉纹。最终断裂区表面粗糙,主要存在韧窝、撕裂脊以及二次裂纹等形貌。在最终断裂区可观察到韧窝,韧窝尺寸随着循环应力的增加,在较高加载频率下,韧窝的尺寸与数量均减小。

关键词： AZ31镁合金疲劳变形孪晶微观组织断口形貌

High Energy Efficiency Dynamic Connected Hybrid Precoding for mm Wave Massive MIMO Systems

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China Communications 2024年第5期21卷 36-44页

作者： Du Ruiyan Liu Huajing Li Tiangui Liu fulai Lab of Key Technology of Millimeter-wave Large-scale MIMO System Northeastern University at QinhuangdaoQinhuangdao066004China School of Computer Science and Engineering Northeastern UniversityShenyang 110819China

This paper considers a high energy efficiency dynamic connected(HEDC)structure,which promotes the practicability and reduces the power consumption of hybrid precoding system by lowresolution phase shifters(PSs).Based on the proposed structure,a new hybrid precoding algorithm is presented to optimize the energy efficiency,namely,HP-HEDC ***,via a new defined effective optimal precoding matrix,the problem of optimizing the analog switch precoding matrix is formulated as a sparse representation ***,the optimal analog switch precoding matrix can be readily obtained by the branch-and-bound ***,the digital precoding matrix optimization problem is modeled as a dictionary update problem and solved by the method of optimal direction(MOD).Finally,the diagonal entries of the analog PS precoding matrix are optimized by exhaustive search independently since PS and antenna is *** results show that the HEDC structure enjoys low power consumption and satisfactory spectral *** proposed algorithm presents at least 50%energy efficiency improvement compared with other algorithms when the PS resolution is set as 3-bit.

关键词： energy efficiency hybrid precoding mmWave optimized resolution phase shifter

Evolution of Diagenetic Fluid of the Dawsonite-Bearing Sandstone in the Jiyang Depression,Eastern China

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Journal of Ocean University of China 2024年第1期23卷 80-98页

作者： LI fulai MA Wenkuan ZHANG Chun WANG Kaining National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Shandong Geological Exploration Institute of China Chemical Geology and Mine Bureau Jinan 250013China

Based on the petrology,isotope geochemistry and fluid inclusions analysis,we established the evolutionary mode of the diagenetic fluid of dawsonite-bearing sandstone in the Jiyang ***-bearing sandstone is characterized by double injection of CO_(2)and oil-gas in the Jiyang Depression that have experienced a relatively complex diagenetic fluid evolution *** diagenetic sequence of secondary minerals involves secondary enlargement of quartz,kaolinite,first-stage calcite,dawsonite,second-stage calcite,ferrocalcite,dolomite and *** charging in the dawsonite-bearing sandstone occurred at around 2.6–0 *** CO_(2)charging event occurred during Dongying tectonism,forming the Pingfangwang CO_(2)gas reservoir,which provided an abundant carbon source for dawsonite *** and oxygen isotopic compositions of dawsonite demonstrate that CO_(2)forming the dawsonite was of an inorganic origin derived from the mantle,and that water mediating the proc-ess during dawsonite precipitation was sequestered brine with a fluid temperature of 82℃.The evolutionary sequence of the diagenetic fluid in the dawsonite-bearing sandstone was:alkaline syngenetic fluids,weak alkaline fluids during organic acid forma-tion,acidic fluids in the early stage of CO_(2)injection,alkaline fluids in the late stage of CO_(2)injection,and weak alkaline fluids during oil and gas *** mode indicates an increase in-HCO_(3)because of the CO_(2)injection,and the loss of Ca^(2+)and Mg^(2+)due to the precipitation of carbonate ***,the evolutionary mode of diagenetic fluids is in good agreement with high HCO_(3)^(-),low Ca^(2+)and low Mg^(2+)composition of the present formation water in the dawsonite-bearing sandstone.

关键词： evolution of diagenetic fluid dawsonite CO_(2)injection and hydrocarbon charging mineral diagenetic sequence iso-topic geochemistry fluid inclusions

Polyphyllin Ⅰ enhances tumor necrosis factor-related apoptosis-inducing ligand-induced inhibition of human osteosarcoma cell growth via downregulating the Wnt/β-catenin pathway

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Journal of Traditional Chinese Medicine 2024年第2期44卷 251-259页

作者： CHANG Junli ZHAO fulai SUN Xingyuan MA Xiaoping ZHAO Peng ZHOU Chujie SHI Binhao GU Wenchao WANG Yongjun yang Yanping Spine Disease Institute Longhua Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200032China Department of Diagnostic and Interventional Radiology University of TsukubaIbaraki 315-0114Japan

OBJECTIVE:To investigate the synergistic effects of polyphyllin Ⅰ(PPⅠ)combined with tumor necrosis factorrelated apoptosis-inducing ligand(TRAIL)on the growth of osteosarcoma cells through downregulating the Wnt/β-catenin signaling ***:Cell viability,apoptosis and cell cycle distribution were examined using cell counting kit-8 and flow cytometry *** morphology of cancer cells was observed with inverted phase contrast *** migration and invasion abilities were examined by xCELLigence real time cell analysis DP system and transwell *** expressions of poly(adenosine diphosphate-ribose)polymerase,C-Myc,Cyclin B1,cyclin-dependent kinases 1,N-cadherin,Vimentin,Active-β-catenin,β-catenin,p-glycogen synthase kinase 3β(GSK-3β)and GSK-3βwere determined by Western blotting ***:PPⅠ sensitized TRAIL-induced decrease of viability,migration and invasion,as well as increase of apoptosis and cell cycle arrest of MG-63 and U-2 OS osteosarcoma *** synergistic effect of PPⅠwith TRAIL in inhibiting the growth of osteosarcoma cells was at least partially realized through the inactivation of Wnt/β-catenin signaling ***:The combination of PPⅠ and TRAIL is potentially a novel treatment strategy of osteosarcoma.

关键词： osteosarcoma tumor necrosis factor-related apoptosis-inducing ligand Wnt signaling pathway beta-catenin polyphyllinⅠ

Metal-Free Synthesis of β-Bromoalkenyl Sulfides via Deoxygenative Bromination/Olefination/Sulfenylation of Ketones with SulfonylHydrazides and Pyridinium Tribromide

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Chinese Journal of Chemistry 2018年第11期36卷 1063-1068页

作者： Yishu Bao Lingyu Zhong Qiaodan Hou Qingfa Zhou fulai yang State Key Laboratory of Natural Medicines Department of Organic Chem- istry China Pharmaceutical University Nanjing Jiangsu 210009 China

A novel metal‐free method for synthesis of β‐bromoalkenyl sulfides via deoxygenative bromination/olefination/sulfenylation process using commercially available ketones, sulfonyl hydrazides and pyridinium tribromide as starting materials has been developed. In this reaction, pyridinium tribromide plays the role of oxidant and substrate, wherein water and molecular nitrogen are generated as environmentally benign by‐products. Preliminary investigation revealed that vinyl bromides were critical intermediate. Importantly, this protocol not only obviates the use of alkynes and traditional sulfenylating agents, but also reveals that ketones can be used as precursors of vinyl bromides.

关键词： ketones sulfonyl hydrazides deoxygenative β‐bromoalkenyl sulfides pyridinium tribromide