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A Study of sr, Nd and O Isotopes of the K-rich Melanocratic Dykes in the Late Mesozoic Gold Field in the Jiaodong Peninsula

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 432-444页

作者： SUN Jinggui, HU Shouxi, LIU Jianmin, SHEN Kun and LING Hongfei Earth Science Institute, Jilin University, Changchun 130062 State Key Laboratory of Research on Metallogenesis of Endogenic Ore Deposits,Nanjing University, Nanjing 210093 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100101 Shandong Institute and Laboratory of Geological Sciences, Jinan 250013 Jilin Univ Inst Earth Sci Changchun 130062 Peoples R China Nanjing Univ State Key Lab Res Metallogenesis Endogen Ore Depo Nanjing 210093 Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100101 Peoples R China Shandong Inst Jinan 250013 Peoples R China Lab Geol Sci Jinan 250013 Peoples R China

Geologic, petrographic and petrochemical studies of the late Mesozoic K-rich melanocratic dykes, including lamprophyres, andesite porphyrites and dacite-porphyry in the gold field system in the Jiaodong Peninsula, China, have shown that these dykes are characterized by rich potassium and alkali but poor titanium. They belong to an ultra-high potassic, shoshonitic and high potassic calc-alkaline rock series. The parental magma has relatively high initial strontium ratios ((87sr/86sr),=0.70895-0.71140) and low (143Nd/144Nd)1 ratios (varying from 0.51135 to 0.51231); and its δ18Osmow, whole rock values vary from +5.8%c to +10.6%c with a mean of +7.1%c. These features suggest that the source region of the magma is an enriched mantle wedge transformed from a continental lithosphere mantle which has experienced metasomatism by mantle-derived fluids with H2O-dominated fluids that were provided during the underthrusting of an ocean crust. The initial magma was generated by low-degree partial melting of the enriched mantle in its mature stage in the back-arc spreading environment. The evolution of magmas is associated with two trends, i.e., fractional crystallization and mixing with or intensive contamination by palaeo-crust materials or metamorphic rocks. The former process is evident in the gold field system of quartz-vein type, whereas the latter is dominated in the gold field system of the altered-rock type. This conclusion is very important for more detailed study of petrogenesis and mineralization through the crust-mantle interaction (exchange) in the Mesozoic in this region.

关键词： late Mesozoic K-rich melanocratic dykes sr Nd and O isotope geochemistry gold field system in the Jiaodong Peninsula

REE AND sr, Nd, Pb ISOTOPIC GEOCHEMISTRY OF HUANGYISHAN BASALT, KUANDIAN, LIAONING, NORTHEAST CHINA

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Science China Chemistry 1990年第6期33卷 747-756页

作者：解广轰王俊文韦克俭刘从强 TATSUMOTO M. BASN A.R. Institute of Geochemistry Academia Sinica Guiyang 550002 PRC U. S. Geological Survey Denver CO 80255 USA Department of Geological Sciences University of Rochester NY 14624 USA

In the light of major element geochemistry, mineral chemistry and REE and isotopic data, the small but apparent isotopic differences between the Cenozoic volcanic rocks east and west of the Tancheng-Lujiang fault are believed to be caused by the mixing and metasomatism of crustal and mantle material in tho mantle source region in response to Pacific plate subduction. The presence of phlogopite and pargasite in mantle xenoliths lends strong support to mantle metasomatism.

关键词： basalt megacryst mantle metasomatism REE sr Nd Pb isotopes.

Three matrix conditions for the reduction of finite automata based on the theory of semi-tensor product of matrices

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Science China(Information Sciences) 2020年第2期63卷 227-229页

作者： Jumei YUE Yongyi YAN Zengqiang CHEN College of Agricultural Engineering Henan University of Science and Technology College of Information Engineering Henan University of Science and Technology College of Computer and Control Engineering Nankai University

Dear editor,Reduction of finite automata (FA) is of great importance because of its practical applications in engineering; for example the memory space of hardware realization grows exponentially with the number of states of FSMs. Existing results for reducing FA can roughly be classified into four categories:merging of states [1], refining of the state

关键词： STP sr Three matrix conditions for the reduction of finite automata based on the theory of semi-tensor product of matrices

Modification and refinement effects of Sb and sr on Mg_(17)Al_(12) and Mg_2Si phases in Mg-12Al-0.7Si alloy

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China Foundry 2016年第5期13卷 310-315页

作者： Zhi-wen Wang Hong-xia Wang Jia-lin Gong Ming Li Wei-li Cheng Wei Liang Shanxi Key Laboratory of Advanced Magnesium Based Materials College of Materials Science and Engineering Taiyuan University of Technology Key Laboratory of Interface Science and Engineering in Advanced Materials Taiyuan University of Technology Ministry of Education

The effects of Sb and sr on the modification and refinement of Mg_(17)Al_(12)and Mg_2Si phases in Mg-12Al-0.7Si alloy were investigated and compared. The microstructure and mechanical properties of Mg-12Al-0.7Si alloy and its modification mechanism by Sb and sr were investigated using a scanning electron microscope(SEM), an energy dispersive spectrometer(EDS), X-ray diffraction(XRD) and differential thermal analysis(DTA). The results indicate that by adding 0.5wt.% Sb to the Mg-12Al-0.7Si alloy, the Mg_(17)Al_(12)phase was refined and broken into some discontinuous island structures. However, some network Mg_(17)Al_(12)phases still can be detected in Mg-12Al-0.7Si-0.09 sr alloy. Therefore, Sb performs better in modification and refinement of Mg_(17)Al_(12)phase than does sr. Small amounts of fine polygonal shaped Mg_2Si phases were found in Mg-12Al-0.7Si-0.5Sb alloy, while the morphology of Mg_2Si phases in Mg-12Al-0.7Si-0.09 sr alloy changed from the coarse Chinese script shapes to fine granule and irregular polygonal shapes, indicating that the effects of modification and refinement on Mg_2Si phase are more significant by adding 0.09 wt.% sr than 0.5wt.% Sb. The ultimate tensile strengths of the Sb and sr modified Mg-12Al-0.7Si alloys were considerably increased both at room temperature and at 200 oC.

关键词： magnesium alloy Sb sr Mg17Al12 phase Mg2Si phase

Seasonal variations in the sr-Nd isotopic compositions of suspended particulate matter in the lower Changjiang River:Provenance and erosion constraints

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Chinese Science Bulletin 2011年第22期56卷 2371-2378页

作者： MAO ChangPing CHEN Jun YUAN XuYin YANG ZhongFang JI JunFeng Institute of Surficial Geochemistry School of Earth Sciences and Engineering Nanjing University Nanjing 210093 China College of Environmental Science and Engineering Hohai University Nanjing 210098 China School of Earth Science and Resources China University ofGeosciences (Beijing) Beijing 100083 China

Suspended particulate matter samples were collected monthly for more than 2 years in Nanjing,China to examine seasonal changes in the sr-Nd isotopic compositions of the lower Changjiang River(CR).The results indicate that the 87sr/86sr ratios of the samples ranges from 0.725352 to 0.738128,and the values ofεNd(0)ranges from-10.55 to-12.29.The sr-Nd isotopic compositions show distinct seasonal variations.The samples had lower 87sr/86sr ratios and higherε Nd(0)values during the flood season than the dry seasons.The seasonal variations primarily reflect the controls of provenance rocks and erosion in different sub-catchments.The relative decrease in 87sr/86sr ratios and the increase inε Nd(0)values during the flood season may reflect an increasing in the mechanical erosion rate in the upper basin and the contribution of more sediment from the upper reaches.The end member values of 87sr/86sr andε Nd(0)of the samples were 0.728254 and?11.26,respectively.

关键词：同位素组成悬浮颗粒物季节变化侵蚀率 sr Nd 长江季节性变化

双钙钛矿srCoFeO阴极材料的制备及其中温固体氧化物燃料电池性能研究(英文)

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无机材料学报 2023年

作者：陈正鹏金芳军李明飞董江波许仁辞徐韩昭熊凯饶睦敏陈创庭李晓伟凌意瀚广东惠州天然气发电有限公司广东省能源集团有限公司长春理工大学广东能源集团科技研究院有限公司中国矿业大学材料科学与物理学院

随着操作温度降低，中温固体氧化物燃料电池(IT-SOFCs)需要更高催化活性的阴极材料以提升电池性能。为此，本研究采用溶胶-凝胶法合成了双钙钛矿sr2CoFeO5+δ(SCF)阴极材料，并阐明了SCF阴极与20%(摩尔分数)Sm2O3掺杂CeO2(SDC)进行不同... 详细信息

随着操作温度降低，中温固体氧化物燃料电池(IT-SOFCs)需要更高催化活性的阴极材料以提升电池性能。为此，本研究采用溶胶-凝胶法合成了双钙钛矿sr2CoFeO5+δ(SCF)阴极材料，并阐明了SCF阴极与20%(摩尔分数)Sm2O3掺杂CeO2(SDC)进行不同比例的复合对电极性能的影响，优化了电极的化学膨胀和面积比电阻(Asr)、进而提升了SOFC单电池的电化学性能。结果表明，SCF作为SOFC阴极在950 ℃退火10 h后与普通电解质具有良好的化学相容性；其中，SCF与SDC按照质量比1∶1复合的样品可以将纯SCF样品的平均热膨胀系数(TEC)从2.44×10-5K-1显著降低到15.4×10-5K-1。此外，SCF–xSDC(SDC含量为质量分数20%， 30%， 40%， 50%)复合阴极的Asr在800 ℃下分别低至0.036、0.034、0.028和0.092 Ω cm2，SCF-40SDC在所有温度范围内都表现出更小的Asr。复合SDC可以优化SCF的三相界面且进一步提高SCF阴极的催化活性，以0.3mm厚La0.9sr0.1Ga0.8Mg0.2O3–δ(LSGM)为电解质的SCF-40SDC单电池(757 mW·cm-2)相比于SCF单电池(684 mW·cm-2)的最大功率密度更优，且超过目前大部分的文献报道。本研究得到SCF-40SDC是一种性能优异的复合阴极材料，有望应用于中温固体氧化物燃料电池。

关键词：固体氧化物燃料电池双钙钛矿阴极 sr CoFeO 复合电极电化学性能

Strontium isotope geochemistry of the Lemachang independent silver ore deposit, northeastern Yunnan, China

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Science China Earth Sciences 2000年第4期43卷 337-346页

作者：邓海琳李朝阳涂光炽周云满王崇武 The Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China No. 1 Geological Party of the Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China

sr isotope geochemical studies (the 87sr/86sr and δ18O-87sr/86sr systems) on the wall rocks and ores from the Lemachang independent Ag deposit in northeastern Yunnan provide strong evidence that the ore-forming fluids had flown through radiogenetically sr-enriched rocks or strata prior to their entry into the locus of ore precipitation, and water-rock interaction is the main mechanism of Ag ore precipitation. The radiogenetically sr-enriched source region may be the Proterozoic basement (the Kunyang and Hekou groups). Moreover, the theoretical modeling of the sr isotopic system indicates that the ore-forming fluids contain as much as 3×10-6 sr with isotopic composition of sr being 0.750 and that of oxygen 7.0‰. The ore-forming temperatures were estimated at 150-250℃ for the carbonate rock-type ores and at 200-260℃ for the clastic rock-type.

关键词： Lemachang northeastern Yunnan independent Ag deposit sr isotope ore-forming fluid.

Microstructures and tensile properties of as-cast Mg-5Sn-1Si magnesium alloy modified with trace elements of Y,Bi,Sb and sr

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China Foundry 2021年第1期18卷 9-17页

作者： He-shuai Yu Xue-feng Guo Hong-bao Cui School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuoHenan454000China Henan International Joint Research Laboratory for High-Performance Light Metallic Materials and Numerical Simulations Henan Polytechnic UniversityJiaozuoHenan454000China

The microstructures and mechanical properties of as-cast Mg-5 Sn-1 Si magnesium alloy modified with trace elements Y,Bi,Sb and sr were investigated and compared.Results show that the microstructure of the as-cast Mg-5 Sn-1 Si alloy consists ofα-Mg,Mg_(2) Si,Mg_(2) Sn and Mg_(2)(Si_xSn_(1-x))phases.After adding 0.8 wt.%Y,0.3 wt.%Bi,0.9 wt.%Sb and 0.9 wt.%sr,respectively into the Mg-5 Sn-1 Si magnesium alloy,Mg_(24)Y_(5),Mg_(3) Bi_(2),Mg_(3) Sb_(2) and Mg_(2) sr phases are precipitated accordingly.Trace elements can refineα-Mg grain and Chinese scriptshaped Mg_(2) Si phase.Refinement efficiency of different trace elements onα-Mg grain and Mg_(2) Si phase is varied.sr element has the best refinement effect,followed by Sb and Bi,while Y has the least refinement effect.Mg-5 Sn-1 Si-0.9 sr alloy has higher tensile properties than the other three modified alloys.The refinement mechanism of Y,Bi and sr elements on Mg-5 Sn-1 Si magnesium alloy can be explained by the growth restriction factors and the solute undercooling.For Mg-5 Sn-1 Si-0.9 Sb alloy,the heterogeneous nuclei of Mg_(3) Sb_(2) phase is the main reason for the refinement of grains and second phases.

关键词： magnesium alloy Mg-5Sn-1Si alloy Y Bi Sb sr Mg2Si phase

sr isotope of fossil foraminiferal assemblages in the Nihewan Group

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Chinese Science Bulletin 1996年第7期41卷 583-586页

作者：王世杰董利敏林文祝李春来汪品先赵泉鸿吴锡浩 Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Laboratory of Marine Geology Tongji University Shanghai 200092 China. Institute of Geomechanics Ministry of Geology and Mineral Resources Beijing 100081 China

Debate on depositional environment about foraminifera-rich strata in many Cenozoiccontinental basins in East China has existed for a long time. Research results achieved inrecent years show that it is difficult to distinguish foraminiferal assemblages in modern saltylakes from those in weakly marine environments such as supratidal zone and lagoon.However, shell geochemistry may be an outlet for this problem because of great differencein chemical and isotopic compositions between lake water and sea water. So fossils ofNonion shansiensis (Evolutononion shangiensis N. Wang), which is a sole foraminiferal speciespreserved in upper part of bed 27 and bed 28 in Xiaodukou section in the Nihewen Ba-sin, were selected for sr isotopic measuremnts. The sequence is larger than 12 m in

关键词： foraminifera sr isotope continental facies Nihewan Group.