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409篇 您的检索式:作者名="Yongsheng Li"
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1Discovery of eclogite and its geological significance in Qiangtang area, central Tibet显示文摘Eclogite is first discovered from Qiang- tang area, central Tibet, which occurs as a lens in the high-pressure metamorphic belt comprising glauco- phane-muscovite schist and garnet-muscovite schist, along the south margin of Lungmu Co-Shuanghu Paleo-Tethys suture. A glaucophane 40Ar/39Ar age of 220 Ma and a phengite 40Ar/39Ar age of 221.9 Ma have been obtained from blueschists associated with eclogite. The rock consists of garnet, omphacite, amphibole, phengite, and rutile, etc, and the jadeite content in omphacite ranges from 32.7% to 38.95%. It is estimated that the temperature of the eclogite is <500℃ and pressure varies in the range of 1.56― 2.35 GPa. The discovery of Qiangtang ecologite fur- ther supports that there is a suture zone of Indo- Chinese epoch in central Qiangtang area, and is very important for discssing the evolution of the pa- leo-ocean and paleo-plate tectonics in this area.LI Cai ZHAI Qingguo DONG Yongsheng HUANG Xiaopeng 2006Chinese Science Bulletin2006,51,9:67
2Applications of LA-ICP-MS in the elemental analyses of geological samples显示文摘Laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS),which is a rapidly developing analytical technique for the analyses of trace elements and isotopes,plays an important role in advancing the study of Earth science,especially with respect to micro-geochemistry.This article reviews the application of LA-ICP-MS in the elemental analysis of solid geological samples.Although LA-ICP-MS has been widely used in the spatial resolution analysis of element compositions and rapid bulk analysis of whole-rock and soil samples,the analysis accuracy is restricted by numerous factors,including the instrumental conditions,the elemental fractionation and matrix effects,the lack of sufficient matrix-matched reference materials,and the strategies for quantitative calibration and sensitivity drift correction.According to the type of samples and the analyte elements,the analysis accuracy can be improved through the optimization of instrument conditions and the adoption of suitable correction strategies and reference materials.LIU YongSheng HU ZhaoChu LI Ming GAO Shan 2013Chinese Science Bulletin2013,58,32:42
3Genetic diversity of rice cultivars (Oryza sativa L.) in China and the temporal trends in recent fifty years显示文摘To understand geographical distribution of the genetic diversity of rice cultivars {Oryza sativa L.) and its trends in recent fifty years in China, 453 ’ accessions were analyzed by 36 microsatellites loci and 42 phenotypic traits. Results revealed that the genetic diversity by SSRs is highly consistent with that by phenotypic traits and the genetic diversity of indica cultivars was higher than that of japonica cultivars; the genetic diversity of cultivars declined from 1950s to 1980s and then increased greatly; among the six rice ecological zones (REZs), genetic diversity of REZTl was the highest and those of REZV and REZVT were the lowest at both DNA and phenotypic level. Jiangsu and Jiangxi provinces in the middle and lower reaches of Yangtze River and Sichuan province in southwest of China were the areas with the highest genetic diversity. Breeders in REZV which is an important japonica rice area but with very low genetic diversity should explore more gene resources to widen the genetic backgrounds of cultivars.QI Yonawen ZHANG Dongling ZHANG Hongliang WANG Meixing SUN Junli WEI Xinghua QIU Zongen TANG Shengxiang CAO Yongsheng WANG Xiangkun LI Zichao 2006Chinese Science Bulletin2006,51,6:27
4Process and mechanism of mountain-root removal of the Dabie Orogen—Constraints from geochronology and geochemistry of post-collisional igneous rocks显示文摘Systematical studies of post-collisional igneous rocks in the Dabie orogen suggest that the thickened mafic lower crust of the orogen was partially melted to form low-Mg#adakitic rocks at 143–131 Ma.Delamination and foundering of the thickened mafic lower crust occurred at 130 Ma,which caused the mantle upwelling and following mafic and granitic magmatic intrusions.Migmatite in the North Dabie zone,coeval with the formation of low-Mg#adakitic intrusions in the Dabie orogen,was formed by partial melting of exhumed ultrahigh-pressure metamorphic rocks at middle crustal level.This paper argues that the partial melting of thickened lower and middle crust before mountain-root collapse needs lithospheric thinning.Based on the geothermal gradient of6.6°C/km for lithospheric mantle and initial partial melting temperature of^1000°C for the lower mafic crust,it can be estimated that the thickness of lithospheric mantle beneath thickened lower crust has been thinned to<45 km when the thickened lower crust was melting.Thus,a two-stage model for mountain-root removal is proposed.First,the lithospheric mantle keel was partially removal by mantle convection at 145 Ma.Loss of the lower lithosphere would increase heat flow into the base of the crust and would cause middle-lower crustal melting.Second,partial melting of the thickened lower crust has weakened the lower crust and increased its gravity instability,thus triggering delamination and foundering of the thickened mafic lower crust or mountain-root collapse.Therefore,convective removal and delamination of the thickened lower crust as two mechanisms of lithospheric thinning are related to causality.LI ShuGuang HE YongSheng WANG ShuiJiong 2013Chinese Science Bulletin2013,58,35:25
5Mineral chemistry and isotope geochemistry of pyrite from the Heilangou gold deposit, Jiaodong Peninsula, Eastern China显示文摘The Heilangou gold deposit is located in the northern QixiaePenglai gold belt, which is one amongst the three large gold belts in the eastern Shandong Province(Jiaodong Peninsula). The ore body has formed within the Guojialing granite. In this study, we report the mineral chemistry of pyrite, as well as the S, Pb,and HeO isotope data of the Heilangou gold deposit. The chemical composition of pyrite in the Heilangou gold deposit indicates that the associated gold deposit is a typical magmatic hydrothermal one. The geochemical signatures and crystal structure of pyrite show that the ore-forming materials have been derived from the crust. The S isotope data of the pyrites from Heilangou show an overall range from 5.5 to7.8& and an average of 6.7&. The S isotope data in this deposit are similar to those from the deposits in the Jiaodong gold belt. The Pb and S isotope variations are small in the Heilangou gold deposit. The206Pb/204Pb,207Pb/204Pb and208Pb/204Pb ratios are 17.4653-17.5958, 15.5105-15.5746 and 38.0749-38.4361, respectively. These data plot between the lower crust and the orogenic belt. The Pb isotope data in the Heilangou gold deposit are similar to those in the Linglong gold deposit. From the Qixia gold area(the Liukou and Majiayao gold deposits) to the MupingeRushan gold belt(Rushan gold deposit) to the ZhaoeYe gold belt(the Linglong, Sanshandao and Jiaojia gold deposits), the206Pb/204Pb ratios progressively increase. The DeO isotope data obtained from quartz separates suggest that the ore-forming fluid was similar to a mixture of magmatic and meteoric waters. These results suggest that the ore-forming elements were primarily from source fluids derived from the lower crust.Yutong Yan Na Zhang Shengrong Li Yongsheng Li 2014Geoscience Frontiers2014,5,2:22
6In-situ U-Pb dating of uraninite by fs-LA-ICP-MS显示文摘In this study,the Pb/U fractionation between zircon and uraninite during femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry(fs-LA-ICP-MS)analysis was studied in detail.The results show significant Pb/U fractionation between zircon and uraninite during fs-LA-ICP-MS analysis that when calibrated against the zircon standard M257,the obtained U-Pb age of the Chinese national uraninite standard GBW04420 is 17%older than the recommended value.Thus,the accurate in-situ U-Pb dating of uraninite by LA-ICP-MS requires matrix-matched external standards for calibration.Uraninite in thin sections of two U-mineralized leucogranite from the Gaudeanmus in Namibia was analyzed by a fs-LA-ICP-MS equipped with a Signal Smooth Device(SSD),using laser spot and frequency of 10μm and 1 Hz,respectively.When calibrated using GBW04420 as the external standard,two samples give weighted mean 206Pb/238U ages of 504±3 Ma(2σ,n=21)and503±3 Ma(2σ,n=22),and only one of two samples yields a concordia U-Pb age of 507±1 Ma(2σ,n=21).These results are consistent with ID-TIMS U-Pb ages of 509±1 and 508±12 Ma and are also indistinguishable from zircon U-Pb upper intercept ages of 506±33 Ma(2σ,n=29)and 501±51 Ma(2σ,n=29).The present study shows that in-situ U-Pb dating of uraninite can deliver more reliable formation ages of the deposit than dating coeval high-U zircon because the latter commonly suffer significant Pb loss after formation.Our results confirm that GBW04420 is an ideal matrix matching standard for in-situ U-Pb dating of uraninite.ZONG KeQing CHEN JinYong HU ZhaoChu LIU YongSheng LI Ming FAN HongHai MENG YanNing 2015Science China Earth Sciences2015,58,10:22
7Deep carbon cycles constrained by a large-scale mantle Mg isotope anomaly in eastern China显示文摘Although deep carbon recycling plays an important role in the atmospheric CO_2 budget and climate changes through geological time,the precise mechanisms remain poorly understood.Since recycled sedimentary carbonate through plate subduction is the main light-δ^(26)Mg reservoir within deep-Earth,Mg isotope variation in mantle-derived melts provides a novel perspective when investigating deep carbon cycling.Here,we show that the Late Cretaceous and Cenozoic continental basalts from 13 regions covering the whole of eastern China have low δ^(26)Mg isotopic compositions,while the Early Cretaceous basalts from the same area and the island arc basalts from circum-Paciic subduction zones have mantle-like or heavy Mg isotopic characteristics.hus,a large-scale mantle low δ^(26)Mg anomaly in eastern China has been delineated,suggesting the contribution of sedimentary carbonates recycled into the upper mantle,but limited into the lower mantle.his large-scale spatial and temporal variation of Mg isotopes in the mantle places severe constraints on deep carbon recycling via oceanic subduction.Shu-Guang Li Wei Yang Shah Ke Xunan Meng Hengci Tian Lijuan Xu Yongsheng He Jian Huang Xuan-Ce Wang Qunke Xia Weidong Sun Xiaoyong Yang Zhong-Yuan Ren Haiquan Wei Yongsheng Liu Fancong Meng Jun Yan 2017National Science Review2017,4,1:23
8Identification of the novel recessive gene pi55(t) conferring resistance to Magnaporthe oryzae显示文摘The elite rice cultivar Yuejingsimiao 2 (YJ2) is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces, which is a higher frequency than that shown by the well-known resistance (R) gene donor cultivars such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F 2 and F 4 populations indicated the resistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a bulked-segregant analysis using genome-wide selected SSR markers with F 4 lines that segregated into 3 resistant (R):1 susceptible (S) or 1R:3S. The recessive R gene on chromosome 8 was further mapped to an interval 1.9 cM/152 kb in length by linkage analysis with genomic position-ready markers in the mapping population derived from an F 4 line that segregated into 1R:3S. Given that no major R gene was mapped to this interval, the novel R gene was designated as pi55(t). Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare, two genes that encode a leucine-rich repeat-containing protein and heavy-metalassociated domain-containing protein, respectively, were suggested as the most likely candidates for pi55(t).HE XiuYing LIU XinQiong WANG Li WANGLing LIN Fei CHENG YongSheng CHEN ZhaoMing LIAO YaoPing PAN QingHua 2012Science China(Life Sciences)2012,55,2:15
9Accuracy of LA-ICPMS zircon U-Pb age determination:An inter-laboratory comparison显示文摘LA-ICPMS zircon U-Pb dating has been greatly advanced and widely applied in the past decade because it is a cheap and fast technique.The internal error of LA-ICPMS zircon U-Pb dating can be better than 1%,but reproducibility(accuracy)is relatively poor.In order to quantitatively assess the accuracy of this technique,zircons from two dioritic rocks,a Mesozoic dioritic microgranular enclave(FS06)and a Neoproterozoic diorite(WC09-32),were dated independently in eight laboratories using SIMS and LA-ICPMS.Results of three SIMS analyses on FS06 and WC09-2 are indistinguishable within error and give a best estimate of the crystallization age of 132.2 and 760.5 Ma(reproducibility is^1%,2RSD),respectively.Zircon U-Pb ages determined by LA-ICPMS in six laboratories vary from 128.3±1.0 to 135.0±0.9 Ma(2SE)for FS06 and from 742.9±3.1 to777.8±4.7 Ma(2SE)for WC09-32,suggesting a reproducibility of^4%(2RSD).Uncertainty produced during LA-ICPMS zircon U-Pb analyses comes from multiple sources,including uncertainty in the isotopic ratio measurements,uncertainty in the fractionation factor calculation using an external standard,uncertainty in the age determination as a result of common lead correction,age uncertainty of the external standards and uncertainty in the data reduction.Result of our study suggests that the uncertainty of LA-ICPMS zircon U-Pb dating is approximately 4%(2RSD).The uncertainty in age determination must be considered in order to interpret LA-ICPMS zircon U-Pb data rationally.LI XianHua LIU XiaoMing LIU YongSheng SU Li SUN WeiDong HUANG HuiQing YI Keewook 2015Science China Earth Sciences2015,58,10:15
10Spectral analysis and self-adjusting mechanism for oscillation phenomenon in hydrogen-oxygen continuously rotating detonation engine显示文摘The continuously rotating detonation engine(CRDE)is a new concept of engines for aircraft and spacecraft.Quasi-stable continuously rotating detonation(CRD)can be observed in an annular combustion chamber,but the sustaining,stabilizing and adjusting mechanisms are not yet clear.To learn more deeply into the CRDE,experimental studies have been carried out to investigate hydrogen-oxygen CRDE.Pressure histories are obtained during each shot,which show that stable CRD waves are generated in the combustor,when feeding pressures are higher than 0.5 MPa for fuel and oxidizer,respectively.Each shot can keep running as long as fresh gas feeding maintains.Close-up of the pressure history shows the repeatability of pressure peaks and indicates the detonation velocity in hydrogen–oxygen CRD,which proves the success of forming a stable CRD in the annular chamber.Spectrum of the pressure history matches the close-up analysis and confirms the CRD.It also shows multi-wave phenomenon and affirms the fact that in this case a single detonation wave is rotating in the annulus.Moreover,oscillation phenomenon is found in pressure peaks and a self-adjusting mechanism is proposed to explain the phenomenon.Liu Yusi Wang Yuhui Li Yongsheng Li Yang Wang Jianping 2015Chinese Journal of Aeronautics2015,28,3:14
11Effect of sintering temperature in argon atmosphere on microstructure and properties of 3D printed alumina ceramic cores显示文摘Alumina ceramics with different sintering temperatures in argon atmosphere were obtained using stereolithography-based 3D printing.The effects of sintering temperature on microstructure and physical and mechanical properties were investigated.The results show that the average particle size,shrinkage,bulk density,crystallite size,flexural strength,Vickers hardness,and nanoindentation hardness increased with the increase in sintering temperature,whereas the open porosity decreased with increasing sintering temperature.No change was observed in phase composition,chemical bond,atomic ratio,and surface roughness.For the sintered samples,the shrinkage in Z direction is much greater than that in X or Y direction.The optimum sintering temperature in argon atmosphere is 1350℃with a shrinkage of 3.0%,3.2%,and 5.5%in X,Y,and Z directions,respectively,flexural strength of 26.7 MPa,Vickers hardness of 198.5 HV,nanoindentation hardness of 33.1 GPa,bulk density of 2.5 g/cm^3,and open porosity of 33.8%.The optimum sintering temperature was 70℃higher than that sintering in air atmosphere when achieved the similar properties.He LI Yongsheng LIU Yansong LIU Qingfeng ZENG Kehui HU Zhigang LU Jingjing LIANG 2020Journal of Advanced Ceramics2020,9,2:13
12Synthesis,characterization,and adsorption performance of Pb(Ⅱ)-imprinted polymer in nano-TiO_2 matrix显示文摘Surface ion-imprinted in combination with sol-gel process was applied to synthesis a new Pb(Ⅱ)-imprinted polymer for selective separation and enrichment of trace Pb(II) from aqueous solution. The prepared material was characterized by using the infrared spectra, X-ray diffractometer, and scanning electron microscopy. The batch experiments were conducted to study the optimal adsorption condition of adsorption trace Pb(Ⅱ) from aqueous solutions on Pb(Ⅱ)-imprinted polymer. The equilibrium was achieved in approximately 4.0 h, and the experimental kinetic data were fitted the pseudo second-order model better. The maximum adsorption capacity was 22.7 mg/g, and the Langmuir equation fitted the adsorption isotherm data. The results of selectivity experiment showed that selectively adsorbed rate of Pb(Ⅱ) on Pb(Ⅱ)-imprinted polymer was higher than all other studied ions. Desorption conditions of the adsorbed Pb(Ⅱ) from the Pb(Ⅱ)-imprinted polymer were also studied in batch experiments. The prepared Pb(Ⅱ)-imprinted polymer was shown to be promising for the separation and enrichment of trace Pb(Ⅱ) from water samples. The adsorption and desorption mechanisms were proposed.LI Chunxiang GAO Jie PAN Jianming ZHANG Zulei YAN Yongsheng 2009Journal of Environmental Sciences2009,21,12:12
13Regional Distribution and Prospects of Potash in China显示文摘中国被几小大陆人块(cratons ) 的合并形成,微,在不同 paleoclimatic 背景的块和 orogenic 带。它可以与另外的大陆人块被相关,但是有它的自己的特定的特征;因此中国的水兵和大陆人的构造环境盐的盆和盐,和钾碱,形成环境有一些特定的特征:部件材料的盐,形成的进程和差异的盐形成,在盐的差别,形成的年龄,移植和集中的多重阶段,以及海洋的盐的盆的小尺寸和在丰富的液体矿物质资源的迟了的阶段和出现的盐的盆的大变化。构造地下室的性质在钾碱盆的形成上施加了关键控制效果。稳定的构造区域为在伪,稳定的区域,和伪的钾碱集中是有利的,并且伪马厩区域在一个本地稳定的构造区域为盐集中和钾碱形成是有利的。大多数中国的主要的古老的盐的盆发生在伪, cratons (大陆人块) ;特别所有海洋的盐的盆与前寒武纪的地下室发生在大陆人块。这些区域是为钾碱搜索的关键的。最相对大,可溶的盐扔的规模在相对稳定的大陆人原子核被开发。根据中国是咸的构造领域的特征,形成盆被定位,诺思中国, Yangtze 和 Tarim, Qaidam 盐 minerogenetic 领域和北 Qiangtang,西方的云南盐 minerogenetic 带可以被区分。他们的盐和钾碱前景将独立被讨论。ZHENG Mianping ZHANG Yongsheng YUAN Heran LIU Xifang CHEN Wenxi LI Jinsuo 2011Acta Geologica Sinica(English Edition)2011,85,1:12
14Lysine-specific demethylase 1 inhibitor rescues the osteogenic ability of mesenchymal stem cells under osteoporotic conditions by modulating H3K4 methylation显示文摘Bone tissue engineering may be hindered by underlying osteoporosis because of a decreased osteogenic ability of autologous seed cells and an unfavorably changed microenvironment in these patients. Epigenetic regulation plays an important role in the developmental origins of osteoporosis; however, few studies have investigated the potential of epigenetic therapy to improve or rescue the osteogenic ability of bone marrow mesenchymal stem cells(BMMSCs) under osteoporotic conditions. Here, we investigated pargyline, an inhibitor of lysine-specific demethylase 1(LSD1), which mainly catalyzes the demethylation of the di- and mono-methylation of H3K4. We demonstrated that 1.5 mmol·L^(- 1)pargyline was the optimal concentration for the osteogenic differentiation of human BMMSCs. Pargyline rescued the osteogenic differentiation ability of mouse BMMSCs under osteoporotic conditions by enhancing the dimethylation level of H3K4 at the promoter regions of osteogenesis-related genes. Moreover, pargyline partially rescued or prevented the osteoporotic conditions in aged or ovariectomized mouse models, respectively. By introducing the concept of epigenetic therapy into the field of osteoporosis, this study demonstrated that LSD1 inhibitors could improve the clinical practice of MSC-based bone tissue engineering and proposes their novel use to treat osteoporosis.Longwei Lv Wenshu Ge Yunsong Liu Guanyou Lai Hao Liu Wenyue Li Yongsheng Zhou 2016Bone Research2016,4,4:11
15Inflammation and tumor progression:signaling pathways and targeted intervention显示文摘Cancer development and its response to therapy are regulated by inflammation,which either promotes or suppresses tumor progression,potentially displaying opposing effects on therapeutic outcomes.Chronic inflammation facilitates tumor progression and treatment resistance,whereas induction of acute inflammatory reactions often stimulates the maturation of dendritic cells(DCs)and antigen presentation,leading to anti-tumor immune responses.In addition,multiple signaling pathways,such as nuclear factor kappa B(NF-kB),Janus kinase/signal transducers and activators of transcription(JAK-STAT),toll-like receptor(TLR)pathways,cGAS/STING,and mitogen-activated protein kinase(MAPK);inflammatory factors,including cytokines(e.g.,interleukin(IL),interferon(IFN),and tumor necrosis factor(TNF)-a),chemokines(e.g.,C-C motif chemokine ligands(CCLs)and C-X-C motif chemokine ligands(CXCLs)),growth factors(e.g.,vascular endothelial growth factor(VEGF),transforming growth factor(TGF)-P),and inflammasome;as well as inflammatory metabolites including prostaglandins,leukotrienes,thromboxane,and specialized proresolving mediators(SPM),have been identified as pivotal regulators of the initiation and resolution of inflammation.Nowadays,local irradiation,recombinant cytokines,neutralizing antibodies,small-molecule inhibitors,DC vaccines,oncolytic viruses,TLR agonists,and SPM have been developed to specifically modulate inflammation in cancer therapy,with some of these factors already undergoing clinical trials.Herein,we discuss the initiation and resolution of inflammation,the crosstalk between tumor development and inflammatory processes.We also highlight potential targets for harnessing inflammation in the treatment of cancer.Huakan Zhao Lei Wu Guifang Yan Yu Chen Mingyue Zhou Yongzhong Wu Yongsheng Li 2021Signal Transduction and Targeted Therapy2021,6,8:11
16Phosphorus Speciation in Wetland Sediments of Zhujiang (Pearl) River Estuary,China显示文摘Phosphorus fractions and adsorption-release characteristics of sediments in the Zhujiang(Pearl) River estuary wetland were investigated.Results showed that the total phosphorus(TP) content in surface sediments ranged from 648.9 mg/kg to 1064.0 mg/kg;inorganic phosphorus(IP) was the major fraction of TP and ranged from 422.5 mg/kg to 643.9 mg/kg.Among the inorganic phosphorus,the main fractions were phosphorus bound to Al and Fe(Fe/Al-P),and calcium-bound phosphorus(Ca-P),accounting for 23%–42% and 21%–67% of IP,respectively.The vertical distribution of TP contents were significantly positive correlated with organic phosphorus(Org-P) and Fe/Al-P contents.The bio-available phosphorus contents in vertical sediments varied from 128.6 mg/kg to 442.9 mg/kg,mainly existed in Fe-Al/P fraction,and increased from the bottom to top sediments.The transport of phosphorus in sediment-water interface was controlled by the soil characteristics.The active Fe and Al content was considered as the main factor that determines adsorption capacity in vegetated marsh wetland.The P buffering capacity of the sediments in vegetated marsh wetland was greater than that in mudflat wetland.The potential risk of eutrophication in the study area is high.Reducing terrestrial phosphorus discharge and preventing the sediment Fe/Al-P release to the interstitial water are the possible solutions to reduce the risk of eutrophication in estuary wetlands,and planting vegetation in estuary wetland can also reduce the release of phosphorus in surface sediment.WANG Lili YE Mei LI Qusheng ZOU Hang ZHOU Yongsheng 2013Chinese Geographical Science2013,23,5:11
17Genesis of the Hongzhen metamorphic core complex and its tectonic implications显示文摘The Hongzhen metamorphic core complex is situated in the Yangtze plate to the east of the Dabie oro- genic belt. Its ductile detachment zone in the foot wall overprints on the metamorphic complex of the Proterozoic Dongling Group. The present profile of the ductile shear zone with consistent SW-dipping mineral elongation lineation shows antiform and reversed S-shape from northeast to southwest respectively. Exposure structures, microstructures and quartz C-axis fabric all indicate top-to-SW movement for the ductile shear zone. Recrystallisation types of quartz and feldspar in the mylonites demonstrate that the shear zone was developed under the amphibolite facies condition and at mid-crust levels. The metamorphic core complex formed in the Early Cretaceous with a muscovite plateau age of 124.8±1.2 Ma. Regional NE-SW extension along a SW-dipping, gentle detachment zone was responsible for formation of the core complex. Intrusion of the Hongzhen granite with a biotite plateau age of 124.8±1.2 Ma rendered the ductile shear zone curved, uplifted and final localization of the core complex. The Hongzhen metamorphic core complex suggests that the Early Cretaceous magma- tism in this region took place under the condition of regional extension and the eastern Yangtze plate also experienced lithospheric thinning.ZHU Guang XIE ChengLong XIANG BiWei HU ZhaoQi WANG YongSheng LI Xing 2007Science China Earth Sciences2007,50,5:10
18Mechanical and dielectric properties of porous and wave-transparent Si3N4–Si3N4 composite ceramics fabricated by 3D printing combined with chemical vapor infiltration显示文摘Porous Si3N4–Si3N4 composite ceramics were fabricated by 3D printing combined with low-pressure chemical vapor infiltration(CVI).This technique could effectively improve the designability of porous Si3N4 ceramics and optimize the mechanical and dielectric properties.The effects of process parameters including the deposition time and heat treatment on the microstructure and properties of porous Si3N4–Si3N4 composite ceramics were studied.The study highlights following:When CVI processing time was increased from 0 to 12 h,the porosity decreased from68.65%to 26.07%and the density increased from 0.99 to 2.02 g/cm3.At the same time,the dielectric constant gradually increased from 1.72 to 3.60;however,the dielectric loss always remained less than0.01,indicating the excellent electromagnetic(EM)wave-transparent performance of porous Si3N4–Si3N4 composite ceramics.The maximum flexural strength of 47±2 MPa was achieved when the deposition time attained 6 h.After heat treatment,the porosity increased from 26.07%to 36.02%and the dielectric constant got a slight increase from 3.60 to 3.70 with the dielectric loss still maintaining lower than 0.01.It has been demonstrated that the porous Si3N4–Si3N4 composite ceramics are a promising structural and EM wave-transparent material suitable for high temperature service.Zanlin CHENG Fang YE Yongsheng LIU Tianlu QIAO Jianping LI Hailong QIN Laifei CHENG Litong ZHANG 2019Journal of Advanced Ceramics2019,8,3:10
19A chlorinated low-bandgap small-molecule acceptor for organic solar cells with 14.1% efficiency and low energy loss显示文摘A new acceptor-donor-acceptor(A-D-A) type small-molecule acceptor NCBDT-4 Cl using chlorinated end groups is reported.This new-designed molecule demonstrates wide and efficient absorption ability in the range of 600–900 nm with a narrow optical bandgap of 1.40 eV. The device based on PBDB-T-SF:NCBDT-4 Cl shows a power conversion efficiency(PCE) of 13.1%without any post-treatment, which represents the best result for all as-cast organic solar cells(OSCs) to date. After device optimizations, the PCE was further enhanced to over 14% with a high short-circuit current density(Jsc) of 22.35 m A cm-2 and a fill-factor(FF) of 74.3%. The improved performance was attributed to the more efficient photo-electron conversion process in the optimal device. To our knowledge, this outstanding efficiency of 14.1% with an energy loss as low as 0.55 eV is among the best results for all single-junction OSCs.Bin Kan Huanran Feng Huifeng Yao Meijia Chang Xiangjian Wan Chenxi Li Jianhui Hou Yongsheng Chen 2018Science China Chemistry2018,61,10:9
20The constraints of strain partitioning and geochronology in Luonan-Luanchuan tectonic belts on Qinling orogenic belt显示文摘The Luonan-Luanchuan tectonic belt lies between the North China Block and Qinling Mountains, in- cluding the Luonan-Luanchuan fault zone and the strong deformation zone to the north of the fault. The ductile shear zone, imbricate brittle fault and duplex structure in the fault zone now are the expression of the same tectonic event in different depth. Such lineation structure exists in the tectonic belts as mineral lineation, elongation lineation, crenulation lineation, sheath folds and so on, indicating NE-directed plate motion. Fold axes and thrusts in the strong deformation zone are inclined to the Luonan-Luanchuan fault zone at small angles. The structures with different natures show a regular pattern, produced during oblique convergence of plates. The convergence factors are as follows:The direction of plate convergence is 22°, 31° and the angle between the plate convergence direction and plate boundary is 73°, 82° respectively in the west and east segment. The Luonan-Luanchuan tectonic belt was deformed strongly in 372 Ma, resulted from Erlangping back-arc ocean basin subduction sin- istrally and obliquely to North China Block during the collision of North China Block and South China Block.SONG ChuanZhong ZHANG GuoWei WANG YongSheng LI JiaHao CHEN ZeChao CAI ZhiChuan 2009Science China Earth Sciences2009,52,3:9
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