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New Zircon U-Pb Age of the Babu Ophiolites in Southeast yunnan,China and Constrains of Plate Subduction Time

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1151-1152页

作者： HUANG Hu DU yuansheng YANG Jianghai yu wenchao State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation Chengdu University of Technology State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Objective The Babu ophiolite in Malipo County of southeastern yunnan is interpreted as remanant ocean crust and represents a possible branch of Paleo-Tethyan Ocean in South China. It consists mainly of mafic and ultramafic rocks. These rocks are very important to understand the evolution of the Paleo-Tethyan Ocean. However, the Babu ophiolite is still disputed and the mafic and ultramafic rocks have been inferred to be part of the Emeishan large igneous province （LIP） by some researchers. In this paper, we present zircon U-Pb data on the metabasalts in Malipo to reveal the formation time of mafic and ultramafic rocks and their tectonic nature.

关键词： Pb ICP MS Th is New Zircon U-Pb Age of the Babu Ophiolites in Southeast yunnan,China and Constrains of Plate Subduction Time of in

Provenance of Lower Carboniferous Bauxite Deposits in Northern Guizhou,China:Constraints from Geochemistry and Detrital Zircon U-Pb Ages

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Journal of Earth Science 2021年第1期32卷 235-252页

作者： Guolin Xiong wenchao yu yuansheng Du Shenfu Weng Dawei Pang Xusheng Deng Jintao Zhou State Key Laboratory of Biogeology and Environmental Geology School of Earth SciencesChina University of GeosciencesWuhan 430078China Innovation Center of Ore Resources Exploration Technology in the Region of Bedrock Ministry of Natural Resources of People's Republic of ChinaGuiyang 550004China Geological Party Guizhou Bureau of Geology and Mineral Exploration and DevelopmentZunyi 563099China Guizhou Geological Survey Guizhou Bureau of Geology and Mineral Exploration and DevelopmentGuiyang 550081China

The Lower Carboniferous Jiujialu Formation bauxite deposits of northern Guizhou Province,China,are a Kazakhstan subtype of karst bauxite *** provenance of the Jiujialu Formation has long been debated,with uncertainty about the formation of the bauxite *** we report new geochemical data that indicate the affinity between the Lower-Middle Ordovician clastic rocks and argillaceous dolostones and the overlying Carboniferous bauxite deposits,all of which are characterized by high Al_(2)0_(3),K2_(O),and∑REE contents,flat post-Archean Australian shale(PAAS)-normalized REE patterns,and uniform immobile element ratios(TiO2/Al_(2)0_(3),Nb/TiO2,and Zr/TiO2).Their similar detrital zircon age distributions further indicate the link between the bauxite deposits and the clastic rocks and argillaceous *** age spectra of clastic rocks of the Lower Silurian Hanchiatien Formation in northern Guizhou match those of the bauxite deposits,with a maximum age peak at-980 Ma and other secondary age peaks,suggesting these clastic rocks may represent the provenance of the bauxite *** youngest detrital zircons(-445 Ma)occur only in the bauxite deposits and are probably sourced from K-bentonite beds of the Ordovician-Silurian *** analyses indicate that the source materials of the bauxite deposits in the Jiujialu Formation are of mixed provenance:Lower-Middle Ordovician aluminosilicate rocks and argillaceous dolostones of the underlying strata,and Lower Silurian clastic rocks and K-bentonite from adjacent areas.A comparison of Early Carboniferous bauxitic provenances in northern and central Guizhou indicates that paleotopography was the major factor controlling the provenance of these bauxite deposits.

关键词： weathering bauxitization karstification chemical weathering Jiujialu Formation

Geochemistry of the Late Paleozoic cherts in the Youjiang Basin:Implications for the basin evolution

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Journal of Palaeogeography 2013年第4期2卷 402-421页

作者： Huang Hu Du yuansheng Yang Jianghai Huang Hongwei Tao Ping Huang Zhiqiang yu wenchao Guo Hua State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences (Wuhan) General Academy of Geological Survey of Guangxi Guizhou Academy of Geological Survey

We analyzed the major and rare earth element compositions of siliceous deposits from the Upper Devonian Liujiang Formation,Lower Carboniferous Luzhai Formation,Lower-Middle Permian Sidazhai Formation and Tapi Formation,which are widely distributed as bedded cherts in the interplatform basinal successions of the Youjiang *** Liujiang Formation and Luzhai Formation cherts generally have high Al/(Al+Fe+Mn) values(0.38-0.94) and are non-hydrothermal *** cherts are generally characterized by moderately negative Ce anomalies and high Y/Ho values relatived to PAAS,indicating that the Youjiang Basin might have evolved into an open rift basin during the Late Devonian-Early *** Sidazhai Formation cherts from Ziyun generally have high Al/(Al+Fe+Mn) values(0.60-0.78),suggesting negligible contribution from a hydrothermal *** Sidazhai Formation cherts from Hechi and the Tapi Formation cherts from Malipo generally have low Al/(Al+Fe+Mn) values(0.09-0.41),indicating an intense hydrothermal *** to the Sidazhai Formation cherts,the Tapi Formation cherts have higher Ce/Ce*values(0.68±0.19) and lower Y/Ho values(41.83±13.27),which may be affected by the terrigenous input from the Vietnam *** Sidazhai Formation cherts from Ziyun and Hechi exhibit negative Ce anomalies(0.43±0.12,0.33±0.17,respectively) with high Y/Ho values(57.44±16.20,46.02±4.27,respectively),resembling the geochemical characteristics of open-ocean basin *** cherts were deposited on a passive continental margin adjacent to the Babu branch ocean,which may have contributed to *** spatial studies on geochemical characteristics of the Late Paleozoic cherts can unravel the evolution of the Youjiang Basin.

关键词： Late Paleozoic chert Liujiang Formation Luzhai Formation Sidazhai Formation Tapi Formation basin evolution Youjiang Basin Yangtze Block Vietnam Block

Transition from the Sedimentary Manganese Deposit to Supergene Manganese Ore in Eastern Hebei， North China: Evidences from Mineralogy and Geochemistry

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Journal of Earth Science 2023年

作者： Lingtong Xu wenchao yu Song Jin Hua Guo Pengfei Ma yuansheng Du Cailong Zhang State Key Laboratory of Geological Processes and Mineral Resources， School of Earth Sciences， China University of Geosciences-Wuhan Innovation Center of Ore Resources Exploration Technology in the Region of Bedrock， Ministry of Natural Resources of People's Republic of China Hebei Institute of Geological Survey State Key Laboratory of Biogeology and Environmental Geology， School of Earth Sciences， China University of Geosciences-Wuhan Geological Exploration Technology Center of Hebei Bureau of Geology and Mineral Exploration and Development

Original sedimentary manganese (Mn) deposits and supergene Mn ores are important Mn resources in China. However， the geochemical information from Chinese supergene Mn ores is scarce， and the relationship between sedimentary Mn deposits and supergene Mn ores is ambiguous. In this study， we collected the original Mn-bearing dolomitic sandstones (ZK20-3 drillcore) and supergene Mn ores (Longmen section) from eastern Hebei， North China for systematic petrographic， mineralogical and geochemical analyses. Our new data help us to figure out the transformation from original Mn-bearing deposits to supergene ores. The main minerals of original Mn-bearing dolomitic sandstones are quartz and feldspar， with minor muscovite， dolomite， rhodochrosite， ankerite， and kutnohorite. Supergene Mn-oxide ores only emerged in the middle part of the Longmen (LM) section， and mainly contain quartz， pyrolusite， cryptomelane， todorokite and occasional dolomite. The possible transformation sequence of Mn minerals is: kutnohorite/rhodochrosite → pyrolusite (Ⅰ) → cryptomelane (todorokite) → todorokite (cryptomelane) → pyrolusite (Ⅱ). For Mn-oxide ores， Fe， Na and Si are enriched but Al， Ca， Mg and K are depleted with the enrichment of Mn. For original and supergene ores， the total rare earth element + ytterbium (∑REY) contents range from 105.68×10-6to 250.56×10-6and from 18.08×10-6to 176.60×10-6， respectively. Original Mn ores have similar slightly LREE-enriched patterns， but the purer Mn-oxide ore shows an HREE-enriched pattern. In the middle part of the LM section， positive Ce anomalies in Mn-oxide ores indicate the precipitation of Ce-bearing minerals. It implies the existence of geochemical barriers， which changed pH and Eh values due to the long-time influence of groundwater.

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Synthesis,crystal structures,electrochemical and spectroscopic properties of ruthenium(Ⅱ) complexes containing diamino-1,3,5-triazine derivatives

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Science China Chemistry 2010年第10期53卷 2099-2105页

作者： CHEN yu, XU wenchao, KOU JunFeng, WEI XuHui, yu BoLe, CHAO Hui & JI LiangNian MOE Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China MOE Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou China

Three Ru(Ⅱ) complexes [Ru(bpy)2(1-IQTNH)](ClO4)2 (1), [Ru(bpy)2(2-QTNH)](ClO4)2 (2) and [Ru(bpy)2(3-IQTNH)](ClO4)2 (3) (bpy = 2,2′-bipyridine, 1-IQTNH = 6-(isoquinolin-1-yl)-1,3,5-triazine-2,4-diamine, 2-QTNH = 6-(quinolin-2-yl)-1,3,5-triazine-2,4-diamine, 3-IQTNH = 6-(isoquinolin-3-yl)-1,3,5-triazine-2,4-diamine) have been synthesized and characterized by elemental analysis, 1H NMR spectroscopy, electrospray ionization mass spectrometry and X-ray crystallography. The electrochemical and spectroscopic properties of the complexes differ from those of [Ru(bpy)3]2+ owing to the structural differences between the ligands and their complexes.

关键词： ruthenium(Ⅱ) complex diamino-1 3 5-triazine crystal structures electrochemistry spectroscopy

Effects of Nitrogen Addition on the Mixed Litter Decomposition in Stipa baicalensis Steppe in Inner Mongolia

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American Journal of Plant Sciences 2016年第3期7卷 547-561页

作者： Wenya Li wenchao yu Long Bai Hongmei Liu Dianlin Yang Department of Horticulture Shenyang Agricultural University Shenyang China Agro-Environmental Protection Institute Ministry of Agriculture Tianjin China Key Laboratory of Original Agro-Environment Quality of Ministry of Agriculture and Tianjin Key Laboratory of Agro-Environment and Safe-Product Tianjin China

During the past two centuries, global changes (i.e., enhanced nitrogen deposition) have exerted profound effects on ecological processes of steppe ecosystems. We used litterbag method and mixed litters of three different plant species tissues (Stipa baicalensis: Sb, Leymus chinensis: Lc and Artemisia frigid: Af), endemic to Stipa baicalensis Steppe, and measured the mass loss of mixtures over 417 days under the N addition treatment. We studied the effect of N addition (N0: no N addition;N15: 1.5 g N/m2·a;N30: 3.0 g N/m2·a;N50: 5.0 g N/m2·a;N100: 10.0 g N/m2·a;N150: 15.0 g N/m2·a) on the rate of mixed litter decomposition and nutrient dynamics change. The decomposition constant (k) of leaf mixtures was higher than that of root mixtures. The k values of leaf mixed combinations were 0.880 (Sb + Lc), 1.231 (Lc + Af), 1.027 (Sb + Lc + Af), respectively. The k value of stem was 0.806 (Lc + Af) and the root mixed combinations were 0.665 (Sb + Lc), 0.979 (Lc + Af) and 1.164 (Sb + Lc + Af), respectively. The results indicated that N addition had significantly effect on the mixed litter decomposition and nutrient releasing. The rate of plant tissues litter decomposition had different response to N addition. In the context of N addition, litter decomposition rate and nutrient dynamics were changed by synthetic effect of decaying time, specie types and N addition dose. Our findings suggested that prairie plants may adapt to environmental change by adjusting litter quality, thus retaining the stability of the steppe ecosystem.

关键词： Grassland Litter Decomposition Mixed Effect N Addition Mass Loss Nutrient Dynamics

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政企关系重构如何影响企业创新?

经济评论 2019年第1期 33-45页

作者：于文超西南政法大学经济学院西南政法大学制度经济学研究中心 401120

本文基于政企关系重构视角,考察地方官员更替对企业创新的影响。利用世界银行2012年中国企业调查数据,研究发现:地方官员更替越频繁,企业创新概率和创新强度越高,且这一效应对于中小企业以及国有股权比重较低的企业而言更强。然而,过于... 详细信息

本文基于政企关系重构视角,考察地方官员更替对企业创新的影响。利用世界银行2012年中国企业调查数据,研究发现:地方官员更替越频繁,企业创新概率和创新强度越高,且这一效应对于中小企业以及国有股权比重较低的企业而言更强。然而,过于频繁的官员更替并非促进企业创新的"良方",在考虑非线性关系的前提下,企业创新概率以及创新强度随着官员更替频率增加呈现倒"U"型变化,且这一关系主要存在于政府管制较强与法制环境较差的地区。进一步地,地方官员更替并未显著影响企业面临的政策不确定性。本文刻画了宏观治理环境变化下的企业创新决策,为理解地方官员更替影响经济发展的具体机制提供了微观证据。

关键词：政企关系企业创新外部治理环境政策不确定性

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政策解读能力如何促进民营企业创新投资

南开经济研究 2021年第1期 205-224页

作者：于文超西南政法大学经济学院、制度经济学研究中心 401120

有效的政策解读能力可以通过丰富创新资源和增进创新意愿来促进民营企业创新。本文利用2012年中国民营企业调查数据,系统评估政策解读能力对民营企业创新投资的影响及其机制。研究发现,良好的政策解读能力会促使民营企业新增更多创新投... 详细信息

有效的政策解读能力可以通过丰富创新资源和增进创新意愿来促进民营企业创新。本文利用2012年中国民营企业调查数据,系统评估政策解读能力对民营企业创新投资的影响及其机制。研究发现,良好的政策解读能力会促使民营企业新增更多创新投资。这一结论在控制内生性偏误与一系列稳健性检验后依然成立。进一步研究表明,政策解读能力可以帮助企业获得更多银行贷款等政策性资源并提高企业的政策熟悉度,这是政策解读能力促进民营企业创新投资的重要机制。本文不仅为理解市场主体政策解读能力的经济效应提供了全新微观证据,更为完善民营企业创新发展的制度环境提供了政策启示。

关键词：政策解读能力民营企业创新投资外部融资政策熟悉度

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国内图书情报领域物联网研究与应用进展

图书馆工作与研究 2018年第6期 71-78页

作者：于文超天津美术学院图书馆

以CNKI中国期刊全文数据库中收录的以"物联网"为主题、以"图书情报与数字图书馆"为学科目录的文献作为数据来源,使用NoteExpress提取高频关键词,借助BibExcel、SPSS和Netdraw软件,采取共词分析法进行聚类及社会网络分析。结果表明,国内... 详细信息

以CNKI中国期刊全文数据库中收录的以"物联网"为主题、以"图书情报与数字图书馆"为学科目录的文献作为数据来源,使用NoteExpress提取高频关键词,借助BibExcel、SPSS和Netdraw软件,采取共词分析法进行聚类及社会网络分析。结果表明,国内图书情报领域物联网研究集中于5个主题:基于RFID技术的智慧图书馆构建;个性化服务与学科服务;图书馆转型与服务创新;图书馆建设;物联网技术与其它新兴技术在图书馆中的综合应用。对这5个主题进行深入分析,以期为图书情报领域物联网技术的理论与应用研究提供参考。

关键词：图书情报领域物联网共词分析聚类分析社会网络分析