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An origin of ultraslow spreading ridges for the Yarlung-Tsangpo ophiolites

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fundamental Research 2022年第1期2卷 74-83页

作者： Chuan-Zhou Liu fu-yuan wu Tong Liu Chang Zhang Wei-Qi Zhang Zhen-Yu Zhang Zhen Zhang wu Wei Yin-Zheng Lina State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

As relics of ancient ocean lithosphere,ophiolites are the most important petrological evidence for marking the sutures and also play a key role in reconstructing plate *** also provide valuable windows for studying crustal accretion and mantle processes occurring at modem ocean *** ophiolites are distributed along the Yarlung-Tsangpo suture and represent the relics of ocean lithosphere of the *** are characterized by an incomplete litho-stratigraphy,of which the mantle section is much thicker than the crustal *** crustal rocks outcropped in the Yarlung-Tsangpo ophiolites are much thinner than normal ocean crusts(~7 km)or even *** settings from which the Yarlung-Tsangpo ophiolites originated remain highly controversial,although an origin of the supra-subduction zone is ***,their incomplete litho-stratigraphy has been commonly attributed to tectonic dismemberment during the late-stage emplacement after their ***,such an incompleteness resembles the ocean lithosphere generated at modem ultraslow spreading ridges,such as the Southwest Indian Ridge(SWIR).In this paper,we present several lines of evidence that support the formation of the Yarlung-Tsangpo ophiolites at ultraslow spreading ridges,during which detachment faults were *** suggests that the Yarlung-Tsangpo ophiolites might represent the ocean core complexes(OCC)in the Neo-Tethys *** OCC with high topography in the seafloor were clogged in the trench and preserved as ophiolites through Indo-Eurasia *** clogging resulted in the demise of an old subduction and a new subduction was re-initiated beneath the clogged OCC.

关键词： Yarlung-Tsangpo ophiolites Tibetan plateau Ultraslow spreading ridges Subduction re-initiation

Clinical application of hepatic venous occlusion for hepatectomy

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Chinese Medical Journal 2008年第9期121卷 806-810页

作者： PAN Ze-ya YANG yuan ZHOU Wei-ping LI Ai-jun fu Si-yuan wu Meng-chao The Third Department of Hepatic Surgery Eastern Hepatobiliary Surgery Hospital Second Military Medical University Shanghai 200438 China

Background Most liver resections require clamping of the hepatic pedicle （Pringle maneuver） to avoid excessive blood loss. But Pringle maneuver can not control backflow bleeding of hepatic vein. Resection of liver tumors involving hepatic veins may cause massive hemorrhage or air embolism from the injuries of the hepatic veins. Although total hepatic vascular exclusion can prevent bleeding of the hepatic veins effectively, it also may result in systemic hemodynamic disturbance because of the inferior vena cava being clamped. Hepatic venous occlusion, a new technique, can control the inflow and outflow of the liver without clamping the vena cava. Methods A total of 71 cases of liver tumors underwent resection with occlusion of more than one of the main hepatic veins. All tumors involved the second porta hepatis and at least one main hepatic vein. Ligation or occlusion with serreflnes, tourniquets and auricular clamps were used in hepatic venous occlusion. Results Of the 71 patients, ligation of the hepatic veins was used in 28 cases, occlusion with a tourniquet in 26, and occlusion with a serrefine in 17. Right hepatic veins were occluded in 38 cases, both right and middle hepatic veins in 2, the common trunk of the left and middle hepatic veins in 24, branches of the left and middle hepatic veins in 2, and all three hepatic veins in 5. Thirty-five cases underwent hemihepatic vascular occlusion, 4 alternate hemihepatic vascular occlusion, 23 portal triad clamping plus selective hepatic vein occlusion, and 9 portal triad clamping plus total hepatic vein occlusion. The third porta hepatis was isolated in 26 cases. The amount of intraoperative blood loss averaged （540±2.83）（range 100 to 1000） ml in the group of total hemihepatic vascular occlusion and in the group of alternate hemihepatic vascular occlusion, （620±317）（range 200-6000） ml in the group of portal triad clamping plus selective or total hepatic vein occlusion. All tumors were completely removed. Conclusions

关键词： liver neoplasms hepatic veins hepatectomy hemorrhage

Timing of destruction of the North China Craton

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Timing of destruction of the North China Craton

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Ri-Xiang Zhu Jin-Hui Yang fu-yuan wu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences

The North China Craton(NCC) is the typical example of destruction of an ancient ***,the destruction mechanism and geodynamic controlling factors still remain enigmatic due to controversy on the timing of destruction,which is the key to understanding the destruction *** on temporal and spatial distributions of the igneous rocks,and their sources and tectonic settings,it is recognized that six stages of tectono-magmatism occurred in the NCC during the Phanerozoic,i.e.,Carboniferous to Early Permian, Late Permian to Middle Triassic,Late Triassic,Jurassic,Early Cretaceous and *** them,Cenozoic magmatism mainly consists of alkali basalts and is found only occasionally in the eastern *** first four stages of magmatism and tectonism,related to the southward subduction of the Paleo-Asian plate and the assembly of Sino-Korean and Yangtze cratons,are locally distributed in limited parts of the NCC, reflecting a multiple stage modification of the NCC from the Late Carboniferous to ***,the intensive development of Early Cretaceous magmatism,extensional deformation and associated gold mineralization, with significant continental crustal growth,indicate that the eastern NCC was destroyed during this time *** destruction was the result of Paleo-Pacific subduction beneath the eastern Asian continent, with lithospheric removal and/or replacement of an ancient cratonic lithosphere by a juvenile oceanic lithosphere.

关键词： North China Craton Destruction Early Cretaceous Magmatism

Loss Aware Feature Attention Mechanism for Class and Feature Imbalance Issue

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Computers, Materials & Continua 2025年第1期82卷 751-775页

作者： Yuewei wu Ruiling fu Tongtong Xing fulian Yin College of Information and Communication Engineering Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large *** imbalance is known to severely affect data quality,and therefore reduce the performance of recommendation *** to the imbalance,machine learning algorithms tend to classify inputs into the positive(majority)class every time to achieve high prediction *** can be categorized such as by features and classes,but most studies consider only class *** this paper,we propose a recommendation system that can integrate multiple networks to adapt to a large number of imbalanced features and can deal with highly skewed and imbalanced datasets through a loss *** propose a loss aware feature attention mechanism(LAFAM)to solve the issue of feature *** network incorporates an attention mechanism and uses multiple sub-networks to classify and learn *** better results,the network can learn the weights of sub-networks and assign higher weights to important *** propose suppression loss to address class imbalance,which favors negative loss by penalizing positive loss,and pays more attention to sample points near the decision *** on two large-scale datasets verify that the performance of the proposed system is greatly improved compared to baseline methods.

关键词： Imbalanced data deep learning e-commerce recommendation loss function big data analysis

An initial study on liner-like Z-pinch loads with a novel configuration on Qiangguang-I facility

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Nuclear Science and Techniques 2021年第9期32卷 116-125页

作者： Zhan-Chang Huang Shi-Jian Meng Ze-Ping Xu Jian-Lun Yang fu-yuan wu Fa-Xin Chen Xiao-Song Yan Rong-Kun Xu Zheng-Hong Li Hong-Wei Xie Yan-Yun Chu Fan Ye Jia-Min Ning Jian Lu Shu-Qing Jiang Rui-Hua Yang Institute of Nuclear Physics and Chemistry Mianyang 621900China E.T.S.I.Aeronauticos y del Espacio Universidad Politecnica de Madrid28040 MadridSpain

A series of liner-like Z-pinch loads with a novel configuration have been investigated experimentally for the first time on Qiangguang-I facility in *** metallic layer is sputtered on the inner surface of the cylindrical SiO 2 substrate *** the preliminary experiment,the electric current flowed through the metallic load during the ***,the currents also flowed through the outer surface of the SiO 2 substrate during the main *** the dielectric length had been increased in the formal experiment,most of the current flowed through the metallic load until radial radiation peak was measured by radiation *** the line mass of the metallic load increases,the peak time of radial radiation also *** ultravi-olet frames indicate that the radiations are nearly azi-muthally uniform at first,but the uniformity becomes worse after radial radiation *** clearly separated boundary between the metal plasmas and the substrate has not been observed in the *** results are discussed and compared with simulation using the one-dimension radiation hydrodynamics code MULTI-IFE.

关键词： Z-pinch Liner-like UV frame Qiangguang-I

Early Eocene sedimentary recycling in the Kailas area,southwestern Tibet:Implications for the initial India–Asia collision

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Early Eocene sedimentary recycling in the Kailas area,southw...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Jian-Gang Wang Xiu-Mian Hu Marcelle BouDagher-Fadel fu-yuan wu Gao-yuan Sun State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum State Key Laboratory of Mineral Deposits Research School of Earth Sciences and EngineeringNanjing University Department of Earth Sciences University College London

Syncollisional sedimentary rocks in the Himalayan orogen record important information about the early history of the India–Asia *** article presents a combined stratigraphic,sedimentologic,micropaleontologic,and provenance data for the Early Eocene clastic strata(Dajin Formation)in the Kailas area,southwestern *** Dajin Formation comprises ungraded and normally graded,matrix-and clast-supported conglomerates,ungraded and cross-stratified sandstones,and massive to poorly laminated *** of the rocks is characterized by subaerial and subaqueous debris flows,waning gravity flows and suspension *** larger benthic foraminifera and the youngest ages of the detrital zircons constrain the depositional age to the earliest Eocene(56–54 Ma).The Dajin Formation contains abundant sandstone and mudstone clasts,indicating significant sedimentary recycling in the source area.U–Pb ages of detrital zircons are mostly clustered at20–54 Ma and have positiveεHf(t)values,suggesting a Gangdese *** of the Dajin Formation are interpreted as having recycled from the forearc strata that were originally derived from the Gangdese magmatic *** immature texture and recycled provenance lead us to propose that deposition of the Dajin Formation was a result of the development of fold-thrusts in the Gangdese *** new results and published data from the coeval strata in the Himalayan orogen indicate that an underfilled foreland basin was initiated soon after the initial India–Asia collision,and the Dajin Formation records the wedge-top depozone of the basin system.

关键词： India–Asia collision Early Eocene Sedimentary recycling Wedge-top basin Southwestern Tibet

Mesozoic accretion of juvenile sub-continental lithospheric mantle beneath South China and its implications:Geochemical and Re-Os isotopic results from Ningyuan mantle xenoliths

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Mesozoic accretion of juvenile sub-continental lithospheric ...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Chuan-Zhou Liu Zhi-Chao Liu fu-yuan wu Zhu-Yin Chu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences

The mechanism for the widespread Mesozoic magmatism in South China has been ascribed to either the paleo-Pacific plate subduction or intra-continental lithospheric *** xenoliths entrained in the Jurassic Ningyuan alkaline basalts from southern Hunan Province,including twelve lherzolites and one harzburgite,have been studied to constrain the composition and age of the Mesozoic sub-continental lithospheric *** lherzolites contain 2.06-4.09 wt.%AlO and 2.03-3.91 wt.%CaO,which are higher than the abundances of these species in the harbzurgite(1.72 wt.%and 1.17 wt.%,respectively).The Cr# of spinel varies from 0.07 to *** contains 3.61 -4.96 wt.%AlO and 0.51 -0.8 wt.%CaO,whereas clinopyroxene contains 4.78-7.32 wt.%AlO and 1.04-2.01 wt.%*** whole rock and mineral compositions suggest that the Ningyuan mantle xenoliths have been subjected to low degrees of partial melting. Modeling of Y and Yb contents of clinopyroxene indicates that the lherzolites have been subjected to 3-5% degrees of partial melting,while the harzburgite has experienced about 12%melting,Clinopyroxene in most Ningyuan mantle xenoliths shows variable depletion in incompatible elements,suggesting that they have been weakly enriched after *** in one sample(TYS01-3) displays strong enrichment in incompatible elements,reflecting the local occurrence of melt *** temperatures estimated by two-pyroxene geothermometry vary from 994 to 1081℃,indicating that the Mesozoic mantle lithosphere has a hot *** lherzolites display consistent highly siderophile element(HSE) patterns and have suprachondritic Ru/Ir and Pd/Ir *** harzburgite shows remarkable depletion in Pt,Pd and *** lherzolites have Os/Os ratios of 0.12116-0.12929,which are higher than that of the harzburgite(0.11681).A correlation between Os/Os and AlO exists among the Ningyuan mantle xenoliths,which if interpreted as an isochron analog yields a model age of -

关键词： Mantle xenoliLhs Re-Os isotopes Highly siderophile elements South China Mesozoic magmatism Mantle accretion

Magmatic evolution of the Western Myanmar Arc documented by U–Pb and Hf isotopes in detrital zircon

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Magmatic evolution of the Western Myanmar Arc documented by ...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Jian-Gang Wang fu-yuan wu Xiu-Cheng Tan Chuan-Zhou Liu State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences State Key Laboratory of Oil and Gas Geology and Exploitation School of Resource and EnvironmentSouthwest Petroleum University

The evolution of the magmatic arc formed along the Asian margin of Neo-Tethys is a key to understand India–Asia *** contrast to the well studied trans-Himalayan magmatic rocks in Tibet,the southeast extension of the arc is still poorly documented in Myanmar,where it is largely buried by sedimentary *** study investigates the magmatic evolution of the western Myanmar arc and the potential along-strike variation of subduction-related magmatism by analyzing U–Pb and Hf isotopes of detrital zircons from the Chindwin Basin in western *** data indicate that the Western Myanmar Arc(WMA)experienced a long-lasting magmatism since the Early Cretaceous,with a main magmatic stage between 110 and 80 Ma and a subordinate magmatic stage at0–40 ***-derived detrital zircons yield positiveεHf(t)values and young model ages(0.1–1.2 Ga),indicating magma generation from a juvenile *** geochronologic and geochemical signatures compare well with those of the Kohistan-Ladakh-Gangdese arc in Tibet,indicating uniform magmatic-arc activity all along the Asian margin of Neo-Tethys.

关键词： Western Myanmar Arc Magmatic history Detrital zircon U–Pb geochronology Hf isotope

Precambrian crustal evolution of the eastern North China Craton as revealed by U-Pb ages and Hf isotopes of detrital zircons from the Proterozoicjing'eryu Formation

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Precambrian crustal evolution of the eastern North China Cra...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Jin-Feng Sun Jin-Hui Yang fu-yuan wu Simon A.Wilde State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Graduate University of the Chinese Academy of Sciences

Simultaneous in situ U-Pb dating,trace element and Hf isotopic analyses have been carried out on detrital zircons obtained from sandstones in the Neoproterozoic Jing’eryu Formation from the Eastern Block, North China Craton(NCC),with the aim of constraining the ages of magmatic and metamorphic events and hence the Precambrian crustal evolution of the *** groups of zircons,i.e.,magmatic and metamorphic in origin,have been identified based on cathodoluminescence images,zircon Ti-temperatures and Th/U *** U-Pb dating shows two main magmatic events with ages of 2.55-2.47 Ga and 1.80-1.70Ga,and four metamorphic events,with ages of 2.51-2.48Ga,1.96-1.90Ga,1.87-1.85Ga and .80 Ga in the *** zircons with ages of .8 Ga have been identified in this study,indicating either these were covered at the time of deposition or the limited presence of 3.8 Ga rocks in the NCC. The Hf isotopic data show the .5Ga magmatic zircons have variableε(t) values,including both positive and negative values and with crustal model ages of 2.7-2.9 Ga,which can be interpreted to indicate mixed sources for their parental rocks,i.e.,ancient crust(3.8 Ga or 3.3 Ga) and depleted mantle, implying significant continental crustal growth at .5 ***,Paleoproterozoic magmatic zircons all have negativeε(t) and Archean Hf model ages,suggesting that their parental rocks were formed from recycled Archean materials. The widespread .5 Ga metamorphism in the Eastern Block,coupled with extensive .5 Ga magmatism and crustal growth,are consistent with a mantle plume beneath the Eastern Block of the NCC during the ***,a progressive increase in～1.85 Ga metamorphic zircon westward across the Eastern Block toward the Trans-North China orogen is best explained by collision between the Eastern and Western blocks at this time.

关键词： North China Craton Eastern Block Crustal evolution Detrital zircon U-Pb age and Hf isotope