This study presents LA–ICP–MS U–Pb dating and whole-rock geochemical analyses of the Late Triassic Gangshan harzburgite in the Qingyuan area,with the aim of elucidating its petrogenesis and further constraining the...This study presents LA–ICP–MS U–Pb dating and whole-rock geochemical analyses of the Late Triassic Gangshan harzburgite in the Qingyuan area,with the aim of elucidating its petrogenesis and further constraining the early Mesozoic tectonic evolution of the eastern segment of the northern margin of the North China Block(NCB).Zircons from the harzburgites exhibit typical oscillatory growth zoning or striped absorp-tion in cathodoluminescence images.U–Pb analyses of zircons yield ages ranging from 2525 Ma to 225 Ma,with two youngest ages(225±7 Ma)indicating that the harzburgites were formed during Late Triassic.Geochemical analyses of the Gangshan harzburgites show that the rocks have low concentrations of SiO_(2)(42.38%–42.85%)and Al_(2)O_(3)(3.31%–3.33%),along with high concentrations of MgO(41.32%–41.76%),Cr(4856×10^(-6)–5191×10^(-6))and Ni(1942×10^(-6)–2041×10^(-6)).They also display low REE abundances(∑REE=4.38×10^(-6)–4.69×10^(-6))and flat REE patterns with low(La/Yb)_(N) ratios(1.24–1.56)and slightly po-sitive Eu anomalies(δEu=1.13–1.16).These features suggest that the Gangshan harzburgites are cumulates of basaltic magma derived from the depleted lithospheric mantle.Combined with previous studies,these Late Triassic mafic–ultramafic rocks,together with coeval granitoids in adjacent regions,constitute a typical bimodal association,suggesting that they formed in a post-orogenic extensional environment after the final closure of the Paleo-Asian Ocean.展开更多
目的探究黄精的研究发展趋势,为黄精栽培、临床研究及产业发展提供参考,为迅速把握其研究内涵和聚焦研究热点提供一定借鉴。方法从中国知网(CNKI)数据库和Web of Science核心合集数据库中检索黄精中、英文献,利用CiteSpace软件从发文量...目的探究黄精的研究发展趋势,为黄精栽培、临床研究及产业发展提供参考,为迅速把握其研究内涵和聚焦研究热点提供一定借鉴。方法从中国知网(CNKI)数据库和Web of Science核心合集数据库中检索黄精中、英文献,利用CiteSpace软件从发文量、发文作者、机构、国家和关键词等方面进行计量学分析;借助incopat数据库的自带分析软件和Excel从专利申请数量、地域、机构及发明人等方面对黄精专利进行分析。结果近20年黄精的中、英文发文量均呈现阶段性的变化,特别是近5年呈快速增长态势。合作网络共现分析发现中、英文文献发文量最多的作者分别是李友元和鲍锦库;发文量最多的研究机构分别为贵州大学农学院和四川大学,其中中心性最高的机构是中国科学院,在机构合作中影响力较大;中国是英文文献发文量最多的国家,且与其他国家间存在较为广泛的联系,在黄精的相关研究领域中占有重要地位。中、英文文献关键词分析发现黄精成分分析从简单的理化性质研究转向化合物分子结构研究;栽培技术从简单的套种、间作等发展为更适宜的林下种植模式;药理作用研究则集中在调节糖脂代谢、防治糖尿病、抗氧化、抗衰老及抗抑郁等方面。目前黄精专利的申请数量处于下行趋势,以中医药文化影响较大的中国等亚洲国家申请专利较多,专利保护内容侧重于黄精的组方配伍。结论黄精研究仍处于发展上升阶段,已经引起国内外学者的广泛关注。目前防治糖尿病、抗氧化、抗衰老、抗肿瘤是黄精的研究重点,且未来仍是主要研究方向;其中,黄精活性成分对肠道菌群结构、机体免疫力的调节作用及其作用靶点和信号通路将成为研究热点;黄精产品深层次开发和创新也将是需要高度关注的发展领域。展开更多
基金Supported by projects of the National Natural Science Foundation of China(Nos.42372063,41722204).
文摘This study presents LA–ICP–MS U–Pb dating and whole-rock geochemical analyses of the Late Triassic Gangshan harzburgite in the Qingyuan area,with the aim of elucidating its petrogenesis and further constraining the early Mesozoic tectonic evolution of the eastern segment of the northern margin of the North China Block(NCB).Zircons from the harzburgites exhibit typical oscillatory growth zoning or striped absorp-tion in cathodoluminescence images.U–Pb analyses of zircons yield ages ranging from 2525 Ma to 225 Ma,with two youngest ages(225±7 Ma)indicating that the harzburgites were formed during Late Triassic.Geochemical analyses of the Gangshan harzburgites show that the rocks have low concentrations of SiO_(2)(42.38%–42.85%)and Al_(2)O_(3)(3.31%–3.33%),along with high concentrations of MgO(41.32%–41.76%),Cr(4856×10^(-6)–5191×10^(-6))and Ni(1942×10^(-6)–2041×10^(-6)).They also display low REE abundances(∑REE=4.38×10^(-6)–4.69×10^(-6))and flat REE patterns with low(La/Yb)_(N) ratios(1.24–1.56)and slightly po-sitive Eu anomalies(δEu=1.13–1.16).These features suggest that the Gangshan harzburgites are cumulates of basaltic magma derived from the depleted lithospheric mantle.Combined with previous studies,these Late Triassic mafic–ultramafic rocks,together with coeval granitoids in adjacent regions,constitute a typical bimodal association,suggesting that they formed in a post-orogenic extensional environment after the final closure of the Paleo-Asian Ocean.
文摘目的探究黄精的研究发展趋势,为黄精栽培、临床研究及产业发展提供参考,为迅速把握其研究内涵和聚焦研究热点提供一定借鉴。方法从中国知网(CNKI)数据库和Web of Science核心合集数据库中检索黄精中、英文献,利用CiteSpace软件从发文量、发文作者、机构、国家和关键词等方面进行计量学分析;借助incopat数据库的自带分析软件和Excel从专利申请数量、地域、机构及发明人等方面对黄精专利进行分析。结果近20年黄精的中、英文发文量均呈现阶段性的变化,特别是近5年呈快速增长态势。合作网络共现分析发现中、英文文献发文量最多的作者分别是李友元和鲍锦库;发文量最多的研究机构分别为贵州大学农学院和四川大学,其中中心性最高的机构是中国科学院,在机构合作中影响力较大;中国是英文文献发文量最多的国家,且与其他国家间存在较为广泛的联系,在黄精的相关研究领域中占有重要地位。中、英文文献关键词分析发现黄精成分分析从简单的理化性质研究转向化合物分子结构研究;栽培技术从简单的套种、间作等发展为更适宜的林下种植模式;药理作用研究则集中在调节糖脂代谢、防治糖尿病、抗氧化、抗衰老及抗抑郁等方面。目前黄精专利的申请数量处于下行趋势,以中医药文化影响较大的中国等亚洲国家申请专利较多,专利保护内容侧重于黄精的组方配伍。结论黄精研究仍处于发展上升阶段,已经引起国内外学者的广泛关注。目前防治糖尿病、抗氧化、抗衰老、抗肿瘤是黄精的研究重点,且未来仍是主要研究方向;其中,黄精活性成分对肠道菌群结构、机体免疫力的调节作用及其作用靶点和信号通路将成为研究热点;黄精产品深层次开发和创新也将是需要高度关注的发展领域。
