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The protective effect of carnosic acid on dextran sulfate sodium-induced colitis based on metabolomics and gut microbiota analysis 被引量:2
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作者 Changhui Du Zhenjie Li +9 位作者 Jing Zhang Ni Yin Lirong Tang Jie Li Jingyin Sun Xiaoqing Yu Wei Chen Hang Xiao Xian Wu Xuexiang Chen 《Food Science and Human Wellness》 SCIE CSCD 2023年第4期1212-1223,共12页
Accumulating evidence suggests that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease(IBD).Carnosic acid(CA)is a major antioxidant component of rosemary and sage.Herein,we in... Accumulating evidence suggests that the gut microbiota plays an important role in the pathogenesis of inflammatory bowel disease(IBD).Carnosic acid(CA)is a major antioxidant component of rosemary and sage.Herein,we investigated the protective effects of dietary CA on dextran sodium sulfate(DSS)-induced colitis mouse model with an emphasis on its impact on the composition and metabolic function of gut microbiota.We found that CA effectively attenuated DSS-stimulated colitis in mice,as evidenced by reduced disease activity index(DAI),and systemic and colonic inflammation.Additionally,CA restored microbial diversity and improved the composition of gut microbiota in DSS-treated mice.Moreover,Spearman’s correlation coefficient showed a significant correlation between the fecal metabolites and the gut microbiota species.Changes in gut microbiota and the correlated metabolites might partially explain CA’s anti-inflammatory effects against colitis.Future clinical trials are needed to determine the therapeutic effects and mechanisms of CA on IBD in humans. 展开更多
关键词 Carnosic acid Inflammatory bowel diseases COLITIS Gut microbiota METABOLITES
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青海湖底沉积物中球状白云石集合体的发现及其地质意义 被引量:30
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作者 于炳松 董海良 +2 位作者 蒋宏忱 李善营 刘英超 《现代地质》 CAS CSCD 北大核心 2007年第1期66-70,共5页
青海湖为盐度低于海水的微咸水湖。为了探索白云石的成因,在青海湖二浪尖以北约15 km的湖底采集了长25cm的沉积物柱状样品。对样品所做的X-衍射矿物物相定量分析表明其中含有2.2%的白云石。文献中也曾报道青海湖底沉积物中含有高达10%... 青海湖为盐度低于海水的微咸水湖。为了探索白云石的成因,在青海湖二浪尖以北约15 km的湖底采集了长25cm的沉积物柱状样品。对样品所做的X-衍射矿物物相定量分析表明其中含有2.2%的白云石。文献中也曾报道青海湖底沉积物中含有高达10%的白云石矿物。对这些含白云石矿物的湖底沉积物所进行的扫描电镜研究发现了其中呈球状、椭球状,大小1-2μm的白云石集合体及其伴生的草莓状黄铁矿的存在。其特征与文献中报道的现代近海高盐度泻湖和萨勃哈中发现的微生物成因的白云石极为相似。这是内陆低盐度环境中此类白云石的首次发现,对于探讨不同盐度环境中白云石的形成机理,促进“白云石问题”的深入研究具有重要的理论意义。 展开更多
关键词 球状白云石 白云石成因 湖底沉积物 青海湖
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青海湖底沉积物的矿物物相及有机质保存研究 被引量:13
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作者 李善营 于炳松 +1 位作者 Hailiang Dong 刘英超 《岩石矿物学杂志》 CAS CSCD 北大核心 2006年第6期493-498,共6页
盐湖沉积环境是烃源岩发育的重要地质环境。本文以青海湖湖底沉积物为例,根据有机质与粘土矿物含量及矿物表面积的关系,分析了矿物学因素对盐湖相富有机质沉积物中有机质保存的影响。研究发现:湖底沉积物中有机质丰富,为上层水中的浮游... 盐湖沉积环境是烃源岩发育的重要地质环境。本文以青海湖湖底沉积物为例,根据有机质与粘土矿物含量及矿物表面积的关系,分析了矿物学因素对盐湖相富有机质沉积物中有机质保存的影响。研究发现:湖底沉积物中有机质丰富,为上层水中的浮游生物和由河流携带来的陆地高等植物两种来源。矿物物相分析发现沉积物中粘土矿物含量达到32.4%,以伊利石为主。沉积物经密度分离后测试发现,有机碳含量与粘土矿物含量及矿物表面积之间具有很好的正相关性,说明粘土矿物吸附是青海湖底沉积物中有机质的主要赋存形式。 展开更多
关键词 有机质 粘土矿物 矿物表面积 吸附 保存机理 青海湖
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西藏拉萨地块过铝质花岗岩中继承锆石的物源区示踪及其古地理意义 被引量:13
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作者 朱弟成 赵志丹 +5 位作者 牛耀龄 王青 DILEK Yildirim 管琪 刘勇胜 莫宣学 《岩石学报》 SCIE EI CAS CSCD 北大核心 2011年第7期1917-1930,共14页
富含继承锆石的过铝质花岗岩一般来源于富铝质岩石(如变泥质岩)的部分熔融,因而分析这些继承锆石的U-Pb年龄可以像分析沉积岩碎屑锆石的U-Pb年龄一样,提供过铝质花岗岩源区物质中碎屑沉积物物源区的丰富信息。本文报道了中部拉萨地块... 富含继承锆石的过铝质花岗岩一般来源于富铝质岩石(如变泥质岩)的部分熔融,因而分析这些继承锆石的U-Pb年龄可以像分析沉积岩碎屑锆石的U-Pb年龄一样,提供过铝质花岗岩源区物质中碎屑沉积物物源区的丰富信息。本文报道了中部拉萨地块早侏罗世过铝质花岗岩的全岩地球化学和锆石U-Pb年代学数据,结合拉萨地块已有二叠纪和晚三叠世过铝质花岗岩的继承锆石年代学数据,总结了目前已有的拉萨地块过铝质花岗岩的继承锆石U-Pb年龄特征(共199个谐和测点)。这些过铝质花岗岩属强过铝质S型花岗岩,其中的继承锆石定义了1250~1100Ma(峰值1181±14Ma)和550~450Ma(峰值494±7Ma)2个最突出的年龄群,分别可比于拉萨地块古生代沉积岩的碎屑锆石年龄峰值(约1170Ma)和寒武纪火山岩的侵位时代,明显不同于西羌塘、安多和特提斯喜马拉雅新元古代-古生代沉积岩中的碎屑锆石年龄频谱。拉萨地块过铝质花岗岩中约1181Ma的继承锆石,可能与拉萨地块古生代沉积岩中的同期碎屑锆石一样,都来自澳大利亚南西部Albany-Fraser造山带和东南极Wilkes等地,而约494的继承锆石,既可能来自澳大利亚西部,也可能来自拉萨地块本地。本文提供了拉萨地块与澳大利亚大陆北缘具有古地理联系的过铝质花岗岩继承锆石U-Pb年龄证据。拉萨地块的研究实践表明,采用过铝质花岗岩继承锆石和古生代沉积岩碎屑锆石相结合的锆石U-Pb年代学方法,可为重建冈瓦纳大陆北缘其它微陆块的古地理和构造岩浆演化提供重要约束。 展开更多
关键词 古地理 拉萨-澳大利亚联系 继承锆石U-Pb年龄 过铝质花岗岩 拉萨地块
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重液材料多钨酸钠在青海湖沉积物重力分离中的应用 被引量:3
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作者 李善营 于炳松 +1 位作者 Hailiang Dong 刘英超 《矿物岩石地球化学通报》 CAS CSCD 2008年第1期69-71,共3页
多钨酸钠是一种无毒、易配制、可循环使用、密度高的新型无机重液。本文利用多钨酸钠重液,用离心机重力分离的方法将青海湖沉积物分成低(≮1.9g/cm^3)、中(1.9~2.8g/cm^3)、高(≥2.8g/cm^3)三个密度组分,平均回收率为96.5%。... 多钨酸钠是一种无毒、易配制、可循环使用、密度高的新型无机重液。本文利用多钨酸钠重液,用离心机重力分离的方法将青海湖沉积物分成低(≮1.9g/cm^3)、中(1.9~2.8g/cm^3)、高(≥2.8g/cm^3)三个密度组分,平均回收率为96.5%。重力分离后的沉积物测试分析发现,有机质主要分布在富粘土矿物的中密度组,揭示了粘土矿物的表面吸附是青海湖底沉积物有机喷的主要赋存形式。 展开更多
关键词 重液 多钨酸钠 重力分离 沉积物 青海湖
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微生物降解蒙脱石层间吸附有机质的实验研究 被引量:6
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作者 于炳松 董海良 韩彭彦 《岩石学报》 SCIE EI CAS CSCD 北大核心 2012年第3期949-960,共12页
近年来,国内外学者意识到,有机质在蒙脱石结构层间的吸附是有机质保存的重要机理之一,然而,目前关于微生物能否降解蒙脱石层间吸附有机质以及降解的程度等尚没有任何实验数据的支撑。本文试图通过人工合成含有层间吸附有机质的蒙脱石,... 近年来,国内外学者意识到,有机质在蒙脱石结构层间的吸附是有机质保存的重要机理之一,然而,目前关于微生物能否降解蒙脱石层间吸附有机质以及降解的程度等尚没有任何实验数据的支撑。本文试图通过人工合成含有层间吸附有机质的蒙脱石,利用海洋和湖泊沉积物中常见的降解有机质的微生物对其进行降解实验,据此探讨有机质的蒙脱石层间吸附在沉积物埋藏过程中对有机质保存的贡献。有机质选择半胱氨酸和甲苯,前者是生物生长所需的一种重要氨基酸,后者大量存在于土壤和沉积物中,多种细菌可以在有碳氢化合物的环境下将其降解。实验菌种选择恶臭假单胞杆菌(Pseudomonas putida)和腐败希瓦氏菌(Shewanella putrefaciens CN32)2种细菌,它们均为海洋和湖泊沉积物中的主导微生物,前者有较强的有机质降解能力,后者为铁的还原菌,厌氧代谢过程中能将蒙脱石结构中的Fe(III)还原为Fe(II)。通过上述不同菌种对蒙脱石层间吸附不同性质有机质的降解实验,结果显示,微生物对蒙脱石层间吸附的有机质的降解方式主要有分泌有机酸直接降解和破坏层间结构释放有机物从而进行降解。代表菌种假单胞菌和希瓦氏菌对半胱氨酸绿脱石及甲苯绿脱石的作用表明,微生物通过分泌有机酸的形式对蒙脱石层间吸附的有机质降解作用很有限,该结构在恒定的有氧和无氧条件下对保存有机质有利;希瓦氏菌在严格无氧条件下通过还原Fe(III)进行代谢,实验表明,无氧条件下,希瓦氏菌可以一定程度破坏矿物结构,释放并消耗有机物,因此,铁还原微生物对蒙脱石层间吸附有机质的保存有一定的影响,但由于微生物对矿物晶体结构的破坏能力有限,故其对层间吸附有机质降解的能力也有限;不同有机物对生物降解过程也有影响,这些影响取决于有机质的特性及有机质与细菌之间的相互作用。绿脱石层间吸附的半胱氨酸对生物生长有利,从而可能促进生物还原Fe(III)作用。相反,甲苯却很明显的抑制了Fe(III)的还原。由此可见,有机质的蒙脱石层间吸附是有机质保存的重要方式之一。 展开更多
关键词 蒙脱石层间吸附 有机质保存 微生物降解 实验研究
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青海湖湖底沉积物中的有机质 被引量:4
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作者 李善营 于炳松 Dong Hailiang 《石油实验地质》 CAS CSCD 北大核心 2006年第4期375-379,共5页
盐湖沉积环境是烃源岩发育的重要地质环境。对青海湖沉积物中有机质、族组分及饱和烃进行测试分析发现,湖体底部水体和浅层沉积物处于弱氧化环境,沉积物中总有机碳含量较高,有机质具陆源高等植物和湖内低等菌藻类复合来源。热演化程度... 盐湖沉积环境是烃源岩发育的重要地质环境。对青海湖沉积物中有机质、族组分及饱和烃进行测试分析发现,湖体底部水体和浅层沉积物处于弱氧化环境,沉积物中总有机碳含量较高,有机质具陆源高等植物和湖内低等菌藻类复合来源。热演化程度极低的青海湖湖底沉积物中碳数分布、主峰碳、碳优势指数(CPI)、姥鲛烷/植烷(Pr/Ph)等参数与我国典型咸化湖环境成熟烃源岩及其生成的原油中相应参数的对比,提供了一套未成熟有机质基本参数的参考值,有利于正确利用这些参数分析有机质的成熟度。 展开更多
关键词 沉积物 有机质 保存机理 成熟度 青海湖
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TMV载体上发生的前体mRNA基因剪接效应研究
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作者 叶新福 Quinn Li 《中国农学通报》 CSCD 2005年第2期31-33,共3页
根据以往的报道,TMV基因只存在于细胞质中且不发生基因剪接,前体mRNA(Pre-mR鄄NA)的剪接只能发生在细胞核中。本研究应用RT-PCR,DNA序列测定及GUS+INTRON的点突变和荧光检测等研究手段,首次发现TMV载体中GUS基因的表达和前体mRNA的剪接... 根据以往的报道,TMV基因只存在于细胞质中且不发生基因剪接,前体mRNA(Pre-mR鄄NA)的剪接只能发生在细胞核中。本研究应用RT-PCR,DNA序列测定及GUS+INTRON的点突变和荧光检测等研究手段,首次发现TMV载体中GUS基因的表达和前体mRNA的剪接同时发生,证明了GUS基因在TMV载体上的剪接效应。 展开更多
关键词 TMV GUS基因 发生 细胞质 研究应用 载体 RT-PCR 前体MRNA 剪接 DNA序列
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微生物对绿脱石中有机质利用的研究 被引量:5
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作者 汪丹 董海良 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2015年第2期301-309,共9页
为了探索黏土矿物中含有的有机质能否被微生物利用以及微生物利用的效率,本文选取富三价铁的黏土矿物绿脱石NAu-2为还原对象,嗜热菌Thermus scotoductus SA-01,以及常温菌Shewanella putrefaciens CN-32为异化铁还原菌,分别在没有外加... 为了探索黏土矿物中含有的有机质能否被微生物利用以及微生物利用的效率,本文选取富三价铁的黏土矿物绿脱石NAu-2为还原对象,嗜热菌Thermus scotoductus SA-01,以及常温菌Shewanella putrefaciens CN-32为异化铁还原菌,分别在没有外加碳源的情况下对NAu-2结构铁进行还原。实验选取化学方法来测试Fe3+还原程度与还原速率,利用X射线粉晶衍射(XRD)、傅里叶转换红外光谱分析仪(FTIR)、扫描电镜(SEM)对黏土矿物还原产物进行矿物学表征,利用总碳/氮分析仪测试黏土矿物释放出来的溶解碳总量以及高效液相色谱仪来分析不同有机组分的含量。实验结果表明相对于常温菌CN-32,嗜热菌SA-01可以有效利用绿脱石中含有的微量有机质作为碳源。由此可知,黏土矿物经微生物作用后发生还原溶解,其吸附的有机质会随着溶解程度的升高不断释放到周围环境中;黏土矿物含有的有机质组分成分复杂,在不同温度环境下释放出来的有机质速率与种类有所不同。 展开更多
关键词 绿脱石 铁还原 有机质 THERMUS scotoductus SA-01 SHEWANELLA PUTREFACIENS CN-32
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中美两国儿童自我概念的比较研究——评定工具对研究结果的影响 被引量:6
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作者 王爱民 任桂英 《中国心理卫生杂志》 CSSCI CSCD 北大核心 2004年第5期294-296,299,共4页
目的 :探讨中美两国儿童自我概念的特点。方法 :选用自评的自我概念评定量表对 183名中国儿童 (男 82名 ,女 10 1名 ,平均年龄 10 82± 0 68岁 )及 160名美国儿童 (男 72名 ,女 88名 ,平均年龄11 0 5± 0 74岁 )进行了... 目的 :探讨中美两国儿童自我概念的特点。方法 :选用自评的自我概念评定量表对 183名中国儿童 (男 82名 ,女 10 1名 ,平均年龄 10 82± 0 68岁 )及 160名美国儿童 (男 72名 ,女 88名 ,平均年龄11 0 5± 0 74岁 )进行了评定。结果 :(1)中国儿童在自我概念评定量表各分量表的得分显著高于美国儿童。(2 )中国女孩在学习成绩 ,同伴关系 ,行为表现 ,与成人交往 ,集体概念 ,外貌 ,自我控制分量表的得分显著高于中国男孩 ;美国男孩在行为表现 ,与成人交往 ,外貌及自我控制量表的得分显著高于美国女孩。结论 :中美儿童自我概念存在显著差异。国家与性别对儿童自我概念存在显著交互作用。 展开更多
关键词 儿童心理学 自我概念 跨文化比较 性别差异 中国 美国
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行动研究及其在教育研究和实践中的意义 被引量:7
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作者 王爱民 刘文 《辽宁师范大学学报(社会科学版)》 2008年第1期44-47,共4页
行动研究是一种探索性的科学研究;是一组有关人员合作找到存在的问题,采取一定的措施和行动来解决这个问题,观察他们所做的努力的效果如何,从而采取进一步的行动。通过深入分析行动研究的本质以及行动研究在教育领域中的应用等问题,力... 行动研究是一种探索性的科学研究;是一组有关人员合作找到存在的问题,采取一定的措施和行动来解决这个问题,观察他们所做的努力的效果如何,从而采取进一步的行动。通过深入分析行动研究的本质以及行动研究在教育领域中的应用等问题,力求为采用行动研究的教育工作者提供理论指导。 展开更多
关键词 行动研究 教育研究 教育实践
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Homogenization temperature and its significance for primary fluid inclusion in halite formed in Chaka salt lake,Qardam basin 被引量:15
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作者 刘兴起 倪培 +1 位作者 董海良 王天刚 《岩石学报》 SCIE EI CAS CSCD 北大核心 2007年第1期113-116,共4页
Halite precipitation with water and air temperature was observed in detail,and homogenization temperature of fluid inclusions in halite formed in ancient and modem Chaka Salt Lake was studied.Halite precipitates mainl... Halite precipitation with water and air temperature was observed in detail,and homogenization temperature of fluid inclusions in halite formed in ancient and modem Chaka Salt Lake was studied.Halite precipitates mainly in August every year and largely precipitates between 13 and 15pm at one day when water temperatures reach 20℃but can seldom reach 30℃.Homogenization temperatures of fluid inclusions in halite formed in Chaka Salt Lake range from 14℃to 38℃with an average of 23.7℃.The number of inclusions appears an obvious peak value at homogenization temperatures between 18~25℃,which probably represent the water temperature in which halite mainly precipitates when water temperatures reach 20℃.Therefore,homogenization temperatures of fluid inclusions in halite formed in Chaka Salt Lake can well reflect the water temperature. 展开更多
关键词 内陆盐湖 石盐流体包裹体 均—温度 指示意义 现代过程
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Diamonds Discovered from High–Cr Podiform Chromitites of Bulqiza,Eastern Mirdita Ophiolite,Albania 被引量:10
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作者 XIONG Fahui YANG Jingsui +6 位作者 ROBINSON Paul T. DILEK Yildirim MILUSHI Ibrahim XU Xiangzhen ZHOU Wenda ZHANG Zhongming RONG He 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期455-468,共14页
Various combinations of diamond, moissanite, zircon, corundum, rutile and titanitehave been recovered from the Bulqiza chromitites. More than 10 grains of diamond have been recovered, most of which are pale yellow to ... Various combinations of diamond, moissanite, zircon, corundum, rutile and titanitehave been recovered from the Bulqiza chromitites. More than 10 grains of diamond have been recovered, most of which are pale yellow to reddish–orange to colorless. The grains are all 100–300 μm in size and mostly anhedral, but with a range of morphologies including elongated, octahedral and subhedral varieties. Their identification was confirmed by a characteristic shift in the Raman spectra between 1325 cm-1 and 1333 cm-1, mostly at 1331.51 cm-1 or 1326.96 cm-1. This investigation extends the occurrence of diamond and moissanite to the Bulqiza chromitites in the Eastern Mirdita Ophiolite. Integration of the mineralogical, petrological and geochemical data of the Bulqiza chromitites suggests their multi–stage formation. Magnesiochromite grains and perhaps small bodies of chromitite formed at various depths in the upper mantle, and encapsulated the ultra–high pressure, highly reduced and crustal minerals. Some oceanic crustal slabs containing the magnesiochromite and their inclusion were later trapped in suprasubduction zones, where they were modified by tholeiitic and boninitic arc magmas, thus changing the magnesiochromite compositions and depositing chromitite ores in melt channels. 展开更多
关键词 DIAMOND Multi–stage formation Bulqiza chromitite OPHIOLITE Albania Proto-Tethys
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Occurrence of Highly Mature Organic Matter in Marine Black Shale Petroleum Source Rocks of Basal Cambrian from Northern Tarim Basin, China 被引量:4
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作者 于炳松 Hailiang DONG +2 位作者 陈建强 陈晓林 梁世友 《Chinese Journal Of Geochemistry》 EI CAS 2004年第2期148-154,共7页
More and more evidence indicates that organic matter (OM) in immature organic-rich sediments and sedimentary rocks is chemically adsorbed onto the outer surfaces of minerals and into interlayer (inner) surfaces of sme... More and more evidence indicates that organic matter (OM) in immature organic-rich sediments and sedimentary rocks is chemically adsorbed onto the outer surfaces of minerals and into interlayer (inner) surfaces of smectitic clay minerals in the form of amorphous molecular-scale carbon. But there have been few reports about the occurrence of highly mature OM in marine black shales (petroleum source rocks). The occurrence of highly mature OM in the black shales of basal Cambrian from northern Tarim Basin is studied in this paper. Based on the comprehensive analyses of total organic carbon contents (TOC), maximum thermolysis temperatures (T-max) of OM, mineral surface areas (MSA), and scanning electronic microscopic (SEM) and transmission electronic microscopic (TEM) observations of the black shales, it is concluded that the highly mature OM in the marine black shales of the basal Cambrian from northern Tarim Basin occurs in particulates ranging in size from 1 to 5 μm in diameter. Through the contrast of the occurrence of the highly mature OM in the black shales with that of the immature ones in modern marine continental margin sediments, some scientific problems are proposed, which are worth to study further in detail. 展开更多
关键词 寒武纪 地层学 塔里木盆地 沉积学 岩石学
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Baculovirus Host-Range 被引量:3
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作者 Suzanne M. Thien Xiao-Wen Cheng 《Virologica Sinica》 SCIE CAS CSCD 2009年第5期436-457,共22页
Baculoviruses are used as microbial insecticides, protein expression vectors, epitope display platforms, and most recently as vectors for gene therapy. Understanding the mechanisms that control baculovirus host-range ... Baculoviruses are used as microbial insecticides, protein expression vectors, epitope display platforms, and most recently as vectors for gene therapy. Understanding the mechanisms that control baculovirus host-range and tissue tropisms are important for assessing their safety and for improving their properties for these biotechnology applications. In the past two decades some progress has been made and several baculovirus genes that influence host-range have been identified. Despite this progress, our understanding of the underlying mechanisms that restrict baculovirus host-range is still limited. Here we review what is currently known about baculovirus genes that influence virus host-range. 展开更多
关键词 杆状病毒 宿主范围 主机 微生物杀虫剂 生物技术应用 表达载体 病毒基因 抗原表位
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Microbial diversity in cold seep sediments from the northern South China Sea 被引量:10
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作者 Yong Zhang Xin Su +5 位作者 Fang Chen Yuanyuan Wang Lu Jiao Hailiang Dong Yongyang Huang Hongchen Jiang 《Geoscience Frontiers》 SCIE CAS 2012年第3期301-316,共16页
South China Sea (SCS) is the largest Western Pacific marginal sea. However, microbial studies have never been performed in the cold seep sediments in the SCS. In 2004, "SONNE" 177 cruise found two cold seep areas ... South China Sea (SCS) is the largest Western Pacific marginal sea. However, microbial studies have never been performed in the cold seep sediments in the SCS. In 2004, "SONNE" 177 cruise found two cold seep areas with different water depth in the northern SCS. Haiyang 4 area, where the water depth is around 3000 m, has already been confirmed for active seeping on the seafloor, such as microbial mats, authigenic carbonate crusts and bivalves. We investigated microbial abundance and diver- sity in a 5.55-m sediment core collected from this cold seep area. An integrated approach was employed including geochemistry and 16S rRNA gene phylogenetic analyses. Here, we show that microbial abun- dance and diversity along with geochemistry profiles of the sediment core revealed a coupled reaction between sulphate reduction and methane oxidation. Acridine orange direct count results showed that microbial abundance ranges from 105 to 106 cells/g sediment (wet weight). The depth-related variation of the abundance showed the same trend as the methane concentration profile. Phylogenetic analysis indicated the presence of sulphate-reducing bacteria and anaerobic methane-oxidizing archaea. The diver- sity was much higher at the surface, but decreased sharply with depth in response to changes in the geochemical conditions of the sediments, such as methane, sulphate concentration and total organic carbon. Marine Benthic Group B, Chloroflexi and JS1 were predominant phylotypes of the archaeal and bacterial libraries, respectively. 展开更多
关键词 16S rRNA Microbial diversity Cold seep Marine sediments Northern South China Sea
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A review of the microbiology of the Rehai geothermal field in Tengchong,Yunnan Province,China 被引量:6
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作者 Brian P.Hedlund Jessica K.Cole +4 位作者 Amanda J.Williams Weiguo Hou Enmin Zhou Wenjun Li Hailiang Dong 《Geoscience Frontiers》 SCIE CAS 2012年第3期273-288,共16页
The Rehai Geothermal Field, located in Tengchong County, in central-western Yunnan Prov- ince, is the largest and most intensively studied geothermal field in China. A wide physicochemical diversity of springs (ambie... The Rehai Geothermal Field, located in Tengchong County, in central-western Yunnan Prov- ince, is the largest and most intensively studied geothermal field in China. A wide physicochemical diversity of springs (ambient to -97 ℃; pH from 〈1.8 to≥9.3) provides a multitude of niches for extremophilic microorganisms. A variety of studies have focused on the cultivation, identification, basic physiology, taxonomy, and biotechnological potential of thermophilic microorganisms from Rehai. Ther- mophilic bacteria isolated from Rehai belong to the phyla Firmicutes and Deinococcus-Thermus. Firmicutes include neutrophilic or alkaliphilic Anoxybacillus, Bacillus, Caldalkalibacillus, Caldanaerobacter, Laceyella, and Geobacillus, as well as thermoacidophilic Alicyclobacillus and Sulfobacillus. Isolates from the Deinococcus-Thermus phylum include several Meiothermus and Thermus species. Many of these bacteria synthesize thermostable polymer-degrading enzymes that may be useful for biotech- nology. The thermoacidophilic archaea Acidianus, Metallosphaera, and Sulfolobus have also been isolated and studied. A few studies have reported the isolation of thermophilic viruses belonging to Siphoviridae (TTSP4 and TTSP10) and Fuselloviridae (STSV1) infecting Thermus spp. and Sulfolobus spp., respectively. More recently, cultivation-independent studies using 16S rRNA gene sequences, shotgun metagenomics, or "'functional gene" sequences have revealed a mtlch broader diversity of micro- organisms than represented in culture. Studies of the gene and mRNA encoding 113e large subunit of the ammonia monooxygenase (amoA) of ammonia-oxidizing Archaea (AOA) and the tetraether lipid cre- narchaeol, a potential hiomarker for AOA, suggest a wide diversity, but possibly low abundance, of ther- mophilic AOA in Rehai. Finally, we introduce the Tengchong Partnerships in International Research and Education (P1RE) project, an international collaboration between Chinese and U.S. scientists with the goal of promoting international and interdisciplinary cooperation to gain a more holistic and gh〉bal view of life in te^estrial geothermal springs. 展开更多
关键词 GeomicrobiologyThermophile YUNNAN REHAI Tengchong PIRE
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Probing the Troodos Ophiolite:IGCP-649 Workshop and Field Excursion Held in Agros-Cyprus 被引量:4
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作者 YANG Jingsui Julian PEARCE Yildirim DILEK 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期1041-1044,共4页
The second IGCP-649 Workshop, held in Agros-Cyprus during 14-20 May 2016, brought together nearly fifty international scientists from around the world, and included a 5-day field excursion on the classic Troodos ophio... The second IGCP-649 Workshop, held in Agros-Cyprus during 14-20 May 2016, brought together nearly fifty international scientists from around the world, and included a 5-day field excursion on the classic Troodos ophiolite. Organized by the IGCP-649 Project Leadership and the Geological Survey Department of Cyprus, the workshop provided a forum for discussions on the latest views and interpretations on the petrogenesis of crustal and upper mantle peridotites in ophiolites, and introduced many young researchers and students to the intemal structure of the classical Troodos ophiolite. This was particularly the case for a large group of Chinese scholars and students, who visited Cyprus and the Troodos ophiolite for the first time. A 4-day profile across the complete ophiolite sequence gave these scientists a first- hand opportunity to examine the lithological and compositional variations within the Cretaceous oceanic crust and to study the igneous and tectonic contacts between them. Lively discussions by the experts and students in front of some of the best 3-dimensional outcrops were most fruitful and allowed all participants to compare the Troodos tectonics with some of ophiolites elsewhere. structure, geochemistry and the other well-documented 展开更多
关键词 Probing the Troodos Ophiolite IGCP-649 Workshop and Field Excursion Held in Agros-Cyprus
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南极洲赖特谷万达盐湖中铬的垂直迁移 被引量:2
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作者 于昇松 W.J.Green G.A.Delanoy 《海洋与湖沼》 CAS CSCD 北大核心 1992年第6期591-598,共8页
南极洲万达湖湖水上部为氧化环境,铬浓度较低,Cr^(6+)占主导地位,主要以CrO_4^(2-)形式存在;下部为还原环境,铬浓度高,Cr^(3+)为主,以Cr(OH)_2^+和Cr(OH)^(2+)形式存在。湖水中锰、铁的氧化物及氢氧化物颗粒对铬离子的吸附和释放过程,... 南极洲万达湖湖水上部为氧化环境,铬浓度较低,Cr^(6+)占主导地位,主要以CrO_4^(2-)形式存在;下部为还原环境,铬浓度高,Cr^(3+)为主,以Cr(OH)_2^+和Cr(OH)^(2+)形式存在。湖水中锰、铁的氧化物及氢氧化物颗粒对铬离子的吸附和释放过程,控制了湖水铬浓度的变化。 展开更多
关键词 盐湖 万达湖 南极洲
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Petrological and Re-Os Isotopic Constraints on the Origin and Tectonic Setting of the Cuobuzha Peridotite, Yarlung Zangbo Suture Zone, SW Tibet, China 被引量:2
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作者 FENG Guangying YANG Jingsui +2 位作者 Yildirim DILEK LIU Fei XIONG Fahui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期10-11,共2页
The Yarlung Zangbo Suture Zone(YZSZ)in southern Tibet includes the remnants of Neotethyan oceanic lithosphere and marks a major suture between the Indian Plate to the south and the Lhasa Terrane of Tibet to the nort... The Yarlung Zangbo Suture Zone(YZSZ)in southern Tibet includes the remnants of Neotethyan oceanic lithosphere and marks a major suture between the Indian Plate to the south and the Lhasa Terrane of Tibet to the north(Dupuis et al.,2005;Yang et al.,2011).In the western part of the YZSZ,the Northern and the Southern sub-belts form two sub-parallel zones of mafic–ultramaficrockassemblageswithoverlapping crystallization ages(Xiong et al.,2011;Hebért et al.,2012;Liu et al.,2015).The upper mantle section of the Cuobuzha ophiolite in the northern sub-belt of the Yarlung–Zangbo Suture Zone(YZSZ)in SW Tibet comprises mainly clinopyroxene(cpx)–rich and depleted harzburgites.Spinels in the cpx-harzburgites show lower Cr#values(12.6–15.1)than the spinels in the harzburgites(26.1–34.5),and the cpx-harzburgites display higher heavy rare earth element concentrations than the depleted harzburgites.The harzburgites have subchondritic Os isotopic compositions(0.11624–0.11699),whereas the cpx-harzburgites have suprachondritic 187Os/188Os ratios(0.12831–0.13125)with higher Re concentrations(0.380-0.575 ppb).The cpx-harzburgites plot in a Re vs.Al2O3 diagram as a result of subsequent addition of Re following the last partial melting event that occurred during mid-ocean ridge melt evolution processes(Uysal et al.,2015).Although these geochemical and isotopic signatures suggest that both peridotite types in the ophiolite represent mid-ocean ridge type upper mantle units,their melt evolution trends reflect different mantle processes.The cpx-harzburgites formed from low-degree partial melting(;%)of a primitive mantle source,and they weresubsequently modified by melt–rock interactions in a mid-ocean ridge environment.The depleted harzburgites,on the other hand,were produced by re-melting of the cpx-harzburgites,which later interacted with MORB-or island arc tholeiite(IAT)-like melts(Fig.1)possibly in a trench-distal backarc spreading center.Our new isotopic and geochemical data from the Cuobuzha peridotites confirm that the Neotethyan upper mantle had highly heterogeneous Os isotopic compositions as a result of multiple melt production and melt extraction events during its seafloor spreading evolution. 展开更多
关键词 Os Yarlung Zangbo Suture Zone China Re
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