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Initiation and evolution of coarse-grained deposits in the Late Quaternary Lake Chenghai source-to-sink system:From subaqueous colluvial apron(subaqueous fans)to Gilbert-type delta

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Journal of Palaeogeography 2022年第2期11卷 194-221页

作者： Dao-Tao Dong Long-Wei Qiu Peng-Jie Ma Guo-Ding Yu Yu-Zhe Wang Shi-Bo Zhou Bao-Liang yang He-Qing Huang yong-qiang yang Xin Li School of Geosciences China University of Petroleum(East China)Qingdao 266580Shandong ProvinceChina SINOPEC Geophysical Research Institute Nanjing 211103Jiangsu ProvinceChina CCCC Second Highway Consultants Co.Ltd. Wuhan 430056Hubei ProvinceChina

Investigating the formation and evolution of coarse-grained deposits in modern lakes and the relevant controlling conditions is indispensable to the prediction of reservoir sandbodies, disaster prediction,and limnological research. The source-to-sink system of coarse-grained deposits in Lake Chenghai, a deep,scarped Late Quaternary lake, was investigated in this study based on 62 outcrops, Advanced Land Observing Satellite(ALOS) digital elevation model(DEM) data, and regional geological survey data. The findings include the following:(1) the source areas of coarse-grained deposits in Lake Chenghai were lithologically classified into carbonate source areas, basaltic source areas and siliciclastic source areas, and were geomorphically categorized as scarp type or confluence type. Subaqueous colluvial aprons have formed downstream of the carbonate source areas and scarp-type basaltic source areas, while Gilbert-type deltas have formed downstream of siliciclastic source areas and confluence-type basaltic source areas.(2) The formation and evolution of coarse-grained deposits are controlled by the sediment flux that evolves in synchrony with the geomorphic evolution of the source areas and the sink regimes. Scarps represent the initial landform of the source areas.Source material rolls off or slides down scarps or forms small-scale debris flows before entering the lake. The source material initially formed subaqueous colluvial apron(synonymous with subaqueous fans) where sufficient space was present to accommodate sediments and the basement angle exceeded than the natural angle of repose. As weathering and denudation have progressed, the initial scarps have transformed into confluencetype slopes, and the source material has formed medium-and large-scale debris flows that have entered the lake, resulting in an increase in sediment flux. Consequently, the subaqueous colluvial aprons have rapidly grown and developed subaerial deposits, which have evolved into larger-scale Gilbert-type deltas that overlie the initial apro

关键词： Coarse-grained deposits Gilbert-type delta Subaqueous colluvial apron Subaqueous fans Source-to-sink Weathering and denudation Sediment input regime Lake Chenghai Quaternary

Pressure nitric acid leaching of alkali-pretreated low-grade limonitic laterite

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Rare Metals 2015年第1期34卷 64-70页

作者： yong-Lu Zhang Cheng-Yan Wang yong-qiang yang Fei Yin Bao-Zhong Ma Institute of Metallurgy Beijing General Research Institute of Mining and Metallurgy

The pressure nitric acid leaching of alkali-pre- treated low-grade limonitic laterite, as well as removing impurity AI（III） and preparing intermediate product of nickel/cobalt sulphide from leaching liquor were investi- gated. After pretreatment, iron exists in the form of amorphous iron oxides, while nickel is adsorbed on the surface of iron oxides in the form of nickel oxide. The preferable pressure leaching conditions are determined as follows： leaching temperature of 458 K, leaching duration of 60 min, initial acidity of nitric acid of 1.90 mol.L-~ and liquid to solid ratio of 3：1 （volume to mass ratio）. Under these conditions, the leaching efficiencies of Ni, Co and A1 are 95 %, 88 % and 55 %, respectively, and that of Fe is less than 1%. The loss rates of Ni and Co are 1.8 % and 1.5 %, respectively, during the step of removing impurity AI（III）. The sulphide precipitation process produces the interim production of nickel/cobalt sulphides, recovering greater than 99 % of Ni and Co in the purified solution. The iron-rich （〉60 %） pressure leaching residue with low Cr, S can be further reclaimed as the raw materials for iron making.

关键词： Limonitic laterite Alkali-pretreated Pressure-leaching Nitric acid Nickel

Geoscience Frontiers 2017 Annual Convention

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Geoscience Frontiers 2018年第2期9卷 595-597页

作者： fei gao lily wang yong-qiang yang geoscience frontiers journal centerchina university of geosciences beijingBeijing 100083China

The 2017 Geoscience Frontiers Annual Convention was held in Beijing, China during October 19e21, 2017 hosted by China University of Geosciences, Beijing (Fig. 1). This convention assembled earth scientists from seven countries, including Australia (Dr. Christopher Spencer and Dr. Stijn Glorie), Korea (Dr. S. Kwon), India (Dr. Shaji Erath), Japan (Dr. Toshiaki Tsunogae and Dr. Masaki Yoshida), Russia (Dr. Inna Safonova), UK (Dr. Nick Roberts), China, and also representatives from Elsevier (Beijing).

关键词： The 2017 Geoscience Frontiers Annual Convention was held in Beijing

Formation of fine crystalline dolomites in lacustrine carbonates of the Eocene Sikou Depression, Bohai Bay Basin, East China

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Petroleum Science 2016年第4期13卷 642-656页

作者： yong-qiang yang Long-Wei Qiu Jay Gregg Zheng Shi Kuan-Hong Yu School of Geosciences China University of Petroleum Department of Geology Oklahoma State University

The genesis of the fine crystalline dolomites that exhibit good to excellent reservoir properties in the upper fourth member of the Eocene Shahejie Formation（Es4s）around the Sikou Sag, Bohai Bay Basin, is uncertain. This paper investigates the formation mechanisms of this fine crystalline dolomite using XRD, SEM, thin section analysis and geochemical data. The stratigraphy of the Sikou lacustrine carbonate is dominated by the repetition of metre-scale, high-frequency deposition cycles, and the amount of dolomite within a cycle increases upward from the cycle bottom. These dolomite crystals are 2–30 μm in length, subhedral to anhedral in shape and typically replace both grains and matrix. They also occur as rim cement and have thin lamellae within ooid cortices. Textural relations indicate that the dolomite predates equant sparry calcite cement and coarse calcite cement. The Sr concentrations of dolomites range from 900 to 1200 ppm. Dolomite δ18O values（-11.3 to-8.2 ‰ PDB） are depleted relative to calcite mudstone（-8.3 to-5.4 ‰ PDB） that precipitated from lake water, while δ13C values（0.06–1.74 ‰ PDB） are within the normal range of calcite mudstone values（-2.13 to 1.99 ‰ PDB）. High87Sr/86Sr values（0.710210–0.710844） indicate that amounts of Ca2＋ and Mg2＋have been derived from the chemical weathering of Palaeozoic carbonate bedrocks. The high strontium concentration indicates that hypersaline conditions were maintainedduring the formation of the dolomites and that the dolomites were formed by the replacement of precursor calcite or by direct precipitation.

关键词： Dolomite Lacustrine carbonate Eocene Sikou Sag Bohai Bay Basin

Effect of titanium dioxide nanoparticles on zebrafish embryos and developing retina

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International Journal of Ophthalmology(English edition) 2014年第6期7卷 917-923页

作者： Ya-Jie Wang Zi-Zi He yang-Wu Fang yang Xu Ya-Nan Chen Guan-Qun Wang yong-qiang yang Zhuo yang Yu-Hao Li Key Laboratory of Tumor Microenviroment and Neurovascular Regulation Nankai University School of Medicine State Key Laboratory of Medicinal Chemical Biology College of ChemistryNankai University

AIM: To investigate the impact of titanium dioxide nanoparticles(Ti O2NPs) on embryonic development and retinal neurogenesis.METHODS: The agglomeration and sedimentation of Ti O2 NPs solutions at different dilutions were observed,and the ultraviolet-visible spectra of their supernatants were measured. Zebrafish embryos were experimentally exposed to Ti O2 NPs until 72 h postfertilization(hpf). The retinal neurogenesis and distribution of the microglia were analyzed by immunohistochemistry and whole mount in situ hybridization.RESULTS: The 1 mg/L was determined to be an appropriate exposure dose. Embryos exposed to Ti O2 NPs had a normal phenotype. The neurogenesis was initiated on time, and ganglion cells, cones and rods were well differentiated at 72 hpf. The expression of fms m RNA and the 4C4 antibody, which were specific to microglia in the central nervous system(CNS), closely resembled their endogenous profile.CONCLUSION: These data demonstrate that short-term exposure to Ti O2 NPs at a low dose does not lead to delayed embryonic development or retinal neurotoxicity.

关键词： titanium dioxide nanoparticles retina microglia zebrafish

Sedimentary environment and the controlling factors of organic-rich rocks in the Lucaogou Formation of the Jimusar Sag, Junggar Basin,NW China

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Petroleum Science 2019年第4期16卷 763-775页

作者： Chang-Sheng Qu Long-Wei Qiu Ying-Chang Cao yong-qiang yang Kuan-Hong Yu School of Geosciences China University of Petroleum Shandong University of Science and Technology Key Laboratory of Deep Oil and Gas Geology and Geophysics (China University of Petroleum) Ministry of Education

The Lucaogou Formation in the Jimusar Sag of the eastern Junggar Basin is an important sedimentary stratum accumulating huge amounts of lacustrine tight oil in China, where organic-rich rocks are commonly observed. Focusing on the Lucaogou Formation, a precise analysis of the inorganic and organic petrology and the inorganic geochemistry characteristics was conducted. The paleoclimate and paleoenvironment during sedimentation of the Lucaogou Formation were established,and the key factors that were controlling the accumulation of organic matter during this time were identified. The results of this study suggest that during the sedimentation of the Lucaogou Formation, the paleoclimate periodically changed from a humid environment to an arid environment. As a result, the salinity of the water and the redox environment fluctuated.During the sedimentation period, the lake showed su cient nutrient supplies and a high primary productivity. The interval studies in the Lucaogou Formation were divided into five sedimentary cycles, where the first, second, and fifth sedimentary cycles consisted of cyclical paleoclimate fluctuations varied from a humid environment to an arid environment and shifted back to a humid environment with levels of salinity from low to high and decreased again. The third and fourth cycles have cyclical fluctuations from a humid to an arid environment and corresponding salinity variation between low and high levels.During the period when organic-rich rocks in the Lucaogou Formation deposited in the Jimusar Sag, the paleoclimate and the water body were suitable for lower aquatic organisms to flourish. As a result, its paleoproductivity was high, especially during the early period of each cycle. A quiet deep water body is likely to form an anoxic environment at the bottom and is also good for accumulation and preservation of organisms. Fine-grained sediments were accumulated at a low deposition rate, with a low dilution of organic matter. Therefore, high paleoproductivity provided a su cient volume of

关键词： Organic-rich rocks Paleoenvironment Lucaogou Formation Jimusar Sag Junggar Basin

Organic-rich rocks;Paleoenvironment;Lucaogou Formation;Jimusar Sag;Junggar Basin

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Petroleum Science 2019年第4期16卷 763-775页

作者： Chang-Sheng Qu Long-Wei Qiu Ying-Chang Cao yong-qiang yang Kuan-Hong Yu School of Geosciences China University of PetroleumQingdao 266580ShandongChina Shandong University of Science and Technology Qingdao 266590ShandongChina Key Laboratory of Deep Oil and Gas Geology and Geophysics (China University of Petroleum)Ministry of EducationQingdao 266580ShandongChina

关键词： Organic-rich rocks Paleoenvironment Lucaogou Formation Jimusar Sag Junggar Basin

激光选区熔化设备及生物医学金属材料的研究与应用进展（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第2期19卷 122-136页

作者： Yu-chao BAI Fan FU Ze-feng XIAO Ming-kang ZHANG Di WANG yong-qiang yang Chang-hui SONG School of Mechanical and Automotive Engineering South China University of Technology

本文主要介绍了华南理工大学(SCUT)在激光选区熔化(SLM)成型设备以及医用金属材料SLM成型的基础研究与应用的最新成果。首先,采用DiMetal-100设备研究316L不锈钢、CoCrMo与Ti6Al4V三种医用金属粉末SLM成型的工艺参数、微观组织和力学性... 详细信息

本文主要介绍了华南理工大学(SCUT)在激光选区熔化(SLM)成型设备以及医用金属材料SLM成型的基础研究与应用的最新成果。首先,采用DiMetal-100设备研究316L不锈钢、CoCrMo与Ti6Al4V三种医用金属粉末SLM成型的工艺参数、微观组织和力学性能。其次,详细介绍了SLM成型316L不锈钢在个性化舌侧正畸托槽和手术导板的应用,SLM成型CoCrMo在膝关节假体和牙冠牙桥的应用,以及SLM成型Ti6Al4V在骨盆骨折接骨板和个性化颅骨修复体方面的研究成果。最后,介绍了SCUT在SLM技术方面的发展方向和研究计划,具体包括实现新型多孔结构的SLM直接成型、实现多种材料SLM一次成型、实现SLM与减材复合成型、增加SLM设备的负反馈系统以及开发陶瓷和新型金属的SLM成型工艺。总结:SCUT对SLM设备及其医学应用进行了长期深入的研究,研究了医用金属材料316L不锈钢、CoCrMo合金以及Ti6Al4V合金的SLM成型工艺和微观组织,获得了性能优异的零件。SCUT成功将SLM成型的316L不锈钢应用于舌侧正畸托槽和手术导板,将SLM成型的CoCrMo合金应用于膝关节假体和牙冠牙桥,以及将SLM成型的Ti6Al4V合金应用于个性化接骨板和颅骨多孔修复体。其中,舌侧正畸托槽和牙冠固定桥已经进入商业应用。目前,SCUT正在进一步开展面向植入体内部结构的设计和制造技术研究,同时开始对SLM多材料成型、SLM与切削复合成型进行研究,并逐步开展SLM设备负反馈系统的开发及陶瓷、锌合金、镍钛合金等SLM成型工艺的研究等。

关键词：激光选区熔化(SLM) 生物医学金属材料工艺参数:微观组织机械性能应用

Irreducible Representations of GL_(n)(C)of Minimal Gelfand-Kirillov Dimension

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Acta Mathematica Sinica,English Series 2024年第3期40卷 639-657页

作者： Zhan qiang BAI yang yang CHEN Dong Wen LIU Bin yong SUN School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China School of Sciences JiangnanUniversityWui214122P.R.China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058P.R.China Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China

In this article,by studying the Bernstein degrees and Goldie rank polynomials,we es-tablish a comparison between the irreducible representations of G=GL_(n)(C)possessing the minimal Gelfand-Kirillov dimension and those induced from finite-dimensional representations of the maximal parabolic subgroup of G of type(n-1,1).We give the transition matrix between the two bases for the corresponding coherent families.

关键词： Bernstein degree coherent continuation Gelfand-Kirillov dimension