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Nb/Ta variations of mafic volcanics on the Archean- Proterozoic boundary: Implications for the Nb/Ta imbalance

Science china Earth Sciences 2005年第8期48卷 1106-1119页

作者： liu yongsheng1,2, gao shan1,2, wang xuance1, {3. shenghong1 & wang jianqi2 1. state key laboratory of Geological processes and mineral resources,{13., wuhan 4.0074. china 2. key laboratory of Continental Dynamics, Department of Geology, Northwest university, Xi’an 710069, china 1. state {1. {3. of Geological processes and mineral resources China University of Geosciences 430074 Wuhan China 2. key {1. of Continental Dynamics Department of Geology Northwest University 710069 Xi’an China

The HFSE and REE of the Precambrian mafic volcanics from the North china craton demonstrate obvious A(Archean)-P(Proterozoic) boundary. The Neoarchean mafic vol- canics show weak correlation between HFSE and TiO2. Their superchondritic Nb/Ta ratio (1..8±1.2) could be attributed to partial melting of mantle peridotite in the presence of garnet. Compared with Neoarchean mafic volcanics, the Paleoproterozoic ones have higher HFSE contents and lower Nb/Ta ratio (1..6±2.9). The significantly elevated HFSE and REE contents of Paleoproterozoic mafic volcanics imply metasomatic enrichment of mantle source, in which Ti-rich silicates could be present as suggested by significant positive correlations between TiO2 and HFSE. The global database of Precambrian mafic volcanics shows a similar A-P boundary. 23.Archean mafic volcanic suites yield an average Nb/Ta ratio of 1..8±1.9 higher than or close to the PM value; Proterozoic mafic volcanics from 28 suites yield an average Nb/Ta ratio of 1..7±4.1.close to the bulk continental crust (BCC) value (1.―1..5). T{1.s, we suggest that the Nb/Ta deficit could be mainly formed in post-Archean time. Archean mafic volcanics could be one of the geochemical reservoirs complementing the low Nb/Ta of the post-Archean continental crust and DM.

关键词： Precambrian mafic volcanics, Nb/Ta deficit, Archean-Proterozoic boundary.

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Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science china Earth Sciences 2006年第9期49卷 904-914页

作者： wang Xiaorui1, gao shan1,2, liu Xiaoming1, YUAN Honglin1, {3. Zhaoc{3.1, ZHANG Hong1,3.& wang xuance4 1. state key laboratory of Continental Dynamics, Department of Geology, Northwest university, Xi`an 710069, china 2. state key laboratory of Geological processes and mineral resources, china university of geosciences, wuhan 4.0074. china 3. Shenyang Institute of Geology and mineral resources, Shenyang 11003., china 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 1. state {1. {3. of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. state {1. laboratory of Geological {3. and mineral resources China University of Geosciences Wuhan 430074 China 3. Shenyang Institute of Geology and mineral {1. Shenyang 110032 China 4. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2 = 52.82-59.3.0}wt%, Al_2O_3.1..1.-1..3.wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03.1.88 μg/g) and Y(1.-20 μg/g) and high Sr (620-1.23.μg/g) and Sr/Y(3.-88), withhigh La_N/Yb_N ratio (1.-25). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(1.3.Nd/^(1.4)Nd(1.0Ma) = 0.51.8-0.51.9, ε_(Nd) (1.0Ma) = -1..6-1..8, ^(87)Sr/^(86)Sr (1.0 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 1.0 to 1.0 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2 for samples with SiO_2 > 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

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Silurian granulite-facies metamorphism,and coeval magmatism and crustal growth in the Tongbai orogen,central china

Silurian granulite-facies metamorphism,and coeval magmatism ...

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中国矿物岩石地球化学学会第1.届学术年会

作者： wang Hao~1,WU Yuan-bao~(1,2),gao shan~1,ZHANG Hong-fei~1, {3. Xiao-chi~1,GONG hu-jun~2,PENG Min~3.wang Jing~4,YUAN Hong-lin~2 1.state key laboratory of Geological processes and mineral resources,Faculty of Earth Sciences,china {13. of geosciences, wuhan 4.0074.china 2.state key laboratory of Continental Dynamics,Department of Geology,Northwest {13.,Xi’an 710069,china 3.Institute of Geophysical and Geochemical Exploration CAGS,Langfang 065000,china 4.Anhui Institute of Geology,Hefei 23.001,china

It is intriguing whether the formation of granulite in an orogenic belt is related to magmatism and crustal *** Tongbai orogen is one of the particular areas in the Qinling-Tongbai-Dabie-Sulu orogen that contains both granulites and associated arc magmatic rocks,and thus is an optimal place to address this ***,the formation age and genesis of the granulites and their relations to the magmatic rocks have not yet been well *** situ LA(MC)-ICPMS U-Pb dating,and trace element and Lu-Hf isotope analyses were undertaken on zircon grains from gneiss,granulite,gabbro and granodiorite *** zircons in three granulite samples and a gneiss sample have core-rim *** cores have oval or rounded shapes,oscillatory zones,high Th/U ratios and variable U-Pb ages,suggesting a detrital *** youngest group of the detrital zircons yields a weighted mean pb/U age of(450-±5) Ma,which is interpreted as the maximum depositional age of their protoliths.A major age cluster is ca.450～490 Ma,corresponding to prolonged arc magmatism in the northern Tongbai and Qinling *** group of ages range from 660 to 950 Ma,implying that the Qinling Group

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Energy-Transfer processes of Xe（6p[1.2]0,6p[3.2]2,and 6p[5/2]2） Atoms under the Condition of Ultrahigh Pumped Power

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Chinese Journal of Chemical Physics 2018年第6期31卷 741-748,733页

作者： shan He Jun-zhi C{1. Dong liu Xue-yang Li Jing-wei Guo Jin-bo liu S{1. {1. {1.i Li Peng-yuan wang Ying Chen Feng-ting Sang Yu-qi Jin key {1. of Chemical Lasers Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China university of Chinese Academy of Sciences Beijing 100049 China

The kinetic processes of Xe(6p[1.2]0, 6p[3.2]2, and 6p[5/2]2) atoms under the focused condition were investigated. The atomic density of the laser prepared {1. significantly increases. Therefore, the probability of the energy-pooling between two high-lying atoms increases. There are three major types of the energy-pooling collisions. The first type is the energy-pooling ionization. Once the excitation laser is focused, the obvious ionization can be observed from the side window whenever the laser prepared {1. is 6p[1.2]0, 6p[3.2]2, or 6p[5/2]2 {1.. Ionization of Xe is attributed to the energy-pooling ionization or a Xe* atom reabsorbing another excitation photon. The second type is energy-pooling with big energy difference. When the 6p[1.2]0 {1. is the laser prepared {1., the energy-pooling collision between two 6p[1.2]0 atoms can produce one 5d[3.2]1.atom and one 6s'[1.2]0 atom. The third type is energy-pooling with small energy difference. The intensities of fluorescence lines are much stronger that five secondary 6p {1.s act as the upper {1.s, and the rising edges of these fluorescence lines are much steeper. The primary mechanism of generating the secondary 6p atoms is energy-pooling collision instead of collision relaxation. Based on the collision probability, the rate of energy-pooling between two 6p[1.2]0 atoms is deduced (6.3.x1.^8s-1.. In addition, the 6s atoms also increase under the focused condition. Therefore, all the fluorescence lines are serious trailing by radiation trapping.

关键词： Energy-pooling Kinetics Xe Ultrahigh pumped power

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Polycomb protein family member CBX7 Regulates Axon Growth and Regeneration

Polycomb protein family member CBX7 Regulates Axon Growth an...

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中国神经科学学会第十二届全国学术会议

作者： Run-shan Duan Gang-Bin Tang Hong-Zhen Du Yi-Wen {1. Pei-Pei liu Ya-Jie Xu Yu-Qiang Zeng S{1.ang-Feng Zhang Rui-Ying wang Zhao-Qian Teng Chang-Mei liu state {1. laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of Sciences Department of Orthopaedic Surgery Affiliated Hospital of Guilin Medical University university of Chinese Academy of Sciences School of Life Sciences University of Science and Technology of China

Objective Neurons in the central nervous system（CNS） lose their intrinsic ability and fail to regenerate, but the underlying mechanisms are largely unknown. Polycomb group（Pc G） proteins, which include PRC1.and PRC2 complexes, function as gene repressors and are involved in the regulation of many biological processes. However, we still don’t know which and how Cbx subunits contribute to neuronal functions in postmitotic neurons, especially in regulation of axon regeneration. Method Cbx family members, si RNA, sh RNA or overexpression plasmid together with EGFP were electroporated into E1. cortical neurons or adult dorsal root ganglion neurons to evaluate whether they can regulate axon growth or regeneration. Results（1. Cbx4, cbx6 and cbx7 gradually increase their expressions in the cortical tissues during development, respond differently after axon injury.（2） Cbx2, cbx7 and cbx8 are {1. regulators of axon regeneration.（3.Cbx7 modulates axon regeneration by repressing SOX1. and GATA4,and downregulation of SOX1. and GATA4 can rescue the axon regeneration ability of neurons lacking CBX7. Conclusion Cbx family members have different functions in axon growth and regeneration and Cbx7 is a novel regulator of axon growth and regeneration.

关键词： Axon CBXs Regeneration

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亚洲大陆边缘沉积学研究进展(201.—2020)

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矿物岩石地球化学通报 2021年第2期40卷 319-336页

作者：石学法乔淑卿杨守业李景瑞万世明邹建军熊志方胡利民姚政权董林森王昆山刘升发刘焱光自然资源部第一海洋研究所自然资源部海洋地质与成矿作用重点实验室山东青岛266061 青岛海洋科学与技术试点国家实验室海洋地质过程与环境功能实验室山东青岛266037 同济大学海洋地质国家重点实验室上海200092 中国科学院海洋研究所中国科学院海洋地质与环境重点实验室山东青岛266071

近十年来,我国在亚洲大陆边缘沉积学和古海洋学研究中取得了突破性进展。在空间上,对北起拉普捷夫海、南至孟加拉湾的广大海域进行了沉积物调查取样,开展了跨纬度"源-汇"过程研究,建立了陆架第四纪高分辨率地层层序,初步揭示了构造运动... 详细信息

近十年来,我国在亚洲大陆边缘沉积学和古海洋学研究中取得了突破性进展。在空间上,对北起拉普捷夫海、南至孟加拉湾的广大海域进行了沉积物调查取样,开展了跨纬度"源-汇"过程研究,建立了陆架第四纪高分辨率地层层序,初步揭示了构造运动、海平面变化、亚洲季风、海冰、海流以及人类活动等因素在不同时空尺度上对亚洲大陆边缘"源-汇"过程的基本控制作用。在南海通过国际大洋钻探获取的沉积记录,发现了低纬区水、碳循环直接响应地球轨道变化的证据,提出了低纬过程也能驱动全球气候变化的新认识。通过现场观测,揭示了台风、风暴潮、热带风暴等对陆架沉积和动力过程的影响,阐述了内孤立波、中尺度涡、等深流和浊流等在南海沉积物输运中的作用。对末次冰期以来暖池、黑潮、北太平洋中层水等的演化及其对沉积作用的影响研究也取得了创新性的成果。未来亚洲大陆边缘沉积学的研究应加强现代沉积过程的长期连续观测,重视地质记录中环境演变信号的精确解译,深化数值模拟技术和海洋沉积大数据的挖掘与使用。

关键词： “源-汇”过程古海洋和古气候海底观测亚洲大陆边缘

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Observation of e^+e^-→D_s^+■^((*)0)K^- and study of the P-wave D_s mesons

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Chinese Physics C 2019年第3期43卷 5-16页

作者： M.Ablikim M.N.Achasov S.Ahmed M.Albrecht M.Alekseev A.Amoroso F.F.An Q.An Y.Bai O.Bakina R.Baldini Ferroli Y.Ban K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere H.Cai X.Cai A.Calcaterra G.F.Cao S.A.Cetin J.Chai J.F.Chang W.L.Chang G.Chelkov G.Chen H.S.Chen J.C.Chen M.L.Chen S.J.Chen Y.B.Chen W.S.Cheng G.Cibinetto F.Cossio H.L.Dai J.P.Dai A.Dbeyssi D.Dedovich Z.Y.Deng A.Denig I.Denysenko M.Destefanis F.De Mori Y.Ding C.Dong J.Dong L.Y.Dong M.Y.Dong Z.L.Dou S.X.Du J.Z.Fan J.Fang S.S.Fang Y.Fang R.Farinelli L.Fava F.Feldbauer G.Felici C.Q.Feng M.Fritsch C.D.Fu Y.Fu Q.gao X.L.gao Y.N.gao Y.G.gao Z.gao B.Garillon I.Garzia A.Gilman K.Goetzen L.Gong W.X.Gong W.Gradl M.Greco L.M.Gu M.H.Gu S.Gu Y.T.Gu A.Q.Guo L.B.Guo R.P.Guo Y.P.Guo A.Guskov Z.Haddadi S.Han X.Q.Hao F.A.Harris K.L.He F.H.Heinsius T.Held Y.K.Heng Z.L.Hou H.M.hu J.F.hu T.hu Y.hu G.S.huang J.S.huang X.T.huang X.Z.huang Z.L.huang N.huesken T.hussain W.Ikegami Andersson W.Imoehl M.Irshad Q.Ji Q.P.Ji X.B.Ji X.L.Ji H.L.Jiang X.S.Jiang X.Y.Jiang J.B.Jiao Z.Jiao D.P.Jin S.Jin Y.Jin T.Johansson N.Kalantar-Nayestanaki X.S.Kang M.Kavatsyuk B.C.Ke I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L.Lavezzi H.Leithoff C.Li Cheng Li D.M.Li F.Li F.Y.Li G.Li H.B.Li H.J.Li J.C.Li J.W.Li Ke Li L.K.Li Lei Li P.L.Li P.R.Li Q.Y.Li W.D.Li W.G.Li X.L.Li X.N.Li X.Q.Li Z.B.Li H.Liang Y.F.Liang Y.T.Liang G.R.Liao L.Z.Liao J.Libby C.X.Lin D.X.Lin B.liu B.J.liu C.X.liu D.liu D.Y.liu F.H.liu Fang liu Feng liu H.B.liu H.L liu H.M.liu huanhuan liu huihui liu J.B.liu J.Y.liu K.Y.liu Kai liu Ke liu Q.liu S.B.liu X.liu Y.B.liu Z.A.liu Zhiqing liu Y.F.Long X.C.Lou H.J.Lu J.D.Lu J.G.Lu Y.Lu Y.P.Lu C.L.Luo M.X.Luo P.W.Luo T.Luo X.L.Luo S.Lusso X.R.Lyu F.C.Ma H.L.Ma L.L.Ma M.M.Ma Q.M.Ma X.N.Ma X.X.Ma X.Y.Ma Y.M.Ma F.E.Maas M.Maggiora S.Maldaner Q.A.Malik A.Mangoni Y.J.Mao Z.P.Mao S.Marcello Z.X.Meng J.G.Messchendorp G.Mezzadri J.Min T.J.Min R.E.Mitchell X.H.Mo Y Institute of High Energy Physics Beijing 100049China Beihang university Beijing 100191China Beijing Institute of Petrochemical Technology Beijing 102617China Bochum Ruhr-{1. D-44780 BochumGermany Carnegie Mellon university PittsburghPennsylvania 15213USA Central china Normal {1. Wuhan 430079China china Center of Advanced Science and Technology Beijing 100190China COMSATS university Islamabad Lahore CampusDefence RoadOff Raiwind Road54000 LahorePakistan Fudan university Shanghai 200443China G.I.Budker Institute of Nuclear Physics SB RAS(BINP) Novosibirsk 630090Russia GSI Helmholtzcentre for Heavy Ion Research GmbH D-64291 DarmstadtGermany Guangxi Normal university Guilin 541004China Guangxi university Nanning 530004China Hangzhou Normal university Hangzhou 310036China Helmholtz Institute Mainz Johann-Joachim-Becher-Weg 45D-55099 MainzGermany Henan Normal university Xinxiang 453007China Henan university of Science and Technology Luoyang 471003China huang{1. College Huangshan 245000China hunan Normal {1. Changsha 410081China hunan {1. Changsha 410082China Indian Institute of Technology Madras Chennai 600036India Indiana university BloomingtonIndiana 47405USA INFN Laboratori Nazionali di Frascati I-00044FrascatiItaly INFN Sezione di Ferrara I-44122FerraraItaly Institute of Physics and Technology Peace Ave.54BUlaanbaatar 13330Mongolia Johannes Gutenberg university of Mainz Johann-Joachim-Becher-Weg 45D-55099 MainzGermany Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia Justus-Liebig-Universitaet Giessen II.Physikalisches InstitutHeinrich-Buff-Ring 16D-35392 GiessenGermany KVI-CART University of GroningenNL-9747 AA GroningenThe Netherlands Lanzhou university Lanzhou 730000China Liaoning university Shenyang 110036China Nanjing Normal university Nanjing 210023China Nanjing university Nanjing 210093China Nankai university Tianjin 300071China Peking university Beijing 100871China shandong {1. Jinan 250100China shanghai

Studies of e^+e~→D_s^+■^((*)0)K^-and the P-wave charmed-strange mesons are performed based on an e^+e^-collision data sample corresponding to an integrated luminosity of 567 pb^(-1. collected with the BESIII detector at s^(1.2)=4.600 GeV. The processes of e^+e^-→D_s^+■^(*0)K^- and D_s^+■~0K^- are observed for the first time and are found to be dominated by the modes D_s^+D_(s1.(253.)^-and D_s^+D_(s2)~*(2573.^-, respectively. The Born cross sections are measured to be σ~B(e^+e^-→D_s^+■^(*0)K^-) =(1..1.2.3.0.8) pb and σ~B(e^+e^-→D_s^+■~0K^-) =(1..4±2.3. 1.6) pb, and the products of Born cross section and the decay branching fraction are measured to be σ~B(e^+e^-→D_s^+D_(s1.(253.)^-+c.c.)·B(D_(s1.(253.)^-→■^(*0)K^-)=(7.5±1.8±0.7) pb and σ~B(e^+e^-→D_s^+D_(s2)~*(2573.^-+ c.c.)·B(D_(s2)~*(2573.^-→■~0 K^-)=(1..7 ± 2.9 ±2.0) pb. For the D_(s1.(253.)^-and D_(s2)~*(2573.^-mesons, the masses and widths are measured to be M(D_(s1.(253.)^-)=(253..7±0.5 ±3.1. MeV/c2, Γ(D_(s1.(253.)^-) =(1.7 ±1.2 ±0.6)MeV, and M(D_(s2)~*(2573.^-)=(2570.7±2.0 ±1.7) MeV/c^2, Γ(D_(s2)~*(2573.^-)=(1..2 ±3.6 ±1.1. MeV. The spin-parity of the D_(s2)~*(2573.^-meson is determined to be J^p= 2^+. In addition, the processes e^+e^-→D_s^+■^((*)0)K^-are searched for using the data samples taken at four(two) center-of-mass energies between 4.41.(4.527) and 4.575 GeV, and upper limits at the 90% confidence level on the cross sections are determined.

关键词： cross section P-wave D_s mesons resonance parameters spin-parity BESIII

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