Microcosm studies on iron and arsenic mobilization from aquifer sediments under different conditions of microbial activity and carbon source   总被引：3，自引：0，他引：3  

Mengyu Duan  Zuoming Xie  Yanxin Wang  Xianjun Xie 《Environmental Geology》2009,57(5):997-1003

Microcosm experiments were conducted to understand the mechanism of microbially mediated mobilization of Fe and As from high arsenic aquifer sediments. Arsenic-resistant strains isolated from aquifer sediments of a borehole specifically drilled for this study at Datong basin were used as inoculated strains, and glucose and sodium acetate as carbon sources for the experiments. In abiotic control experiments, the maximum concentrations of Fe and As were only 0.47 mg/L and 0.9 μg/L, respectively. By contrast, the maximum contents of Fe and As in anaerobic microcosm experiments were much higher (up to 1.82 mg/L and 12.91 μg/L, respectively), indicating the crucial roles of microbial activities in Fe and As mobilization. The observed difference in Fe and As release with different carbon sources may be related to the difference in growth pattern and composition of microbial communities that develop in response to the type of carbon sources.  相似文献   

维西—景洪裂陷带初步研究   总被引：6，自引：0，他引：6  

王宝禄  李文昌 《云南地质》2001,20(1):39-45

位于兰坪－思茅坳陷带西侧近南北向的维西－无量山－景洪地质块体，根据地球物理资料结合地质综合分析，具有裂陷带的特征，自泥盆纪开始的地幔上隆，形成隆起带，地壳产生东西向拉张，局部出现火山活动，石炭纪至三叠纪以中酸性为主的火山岩浆大量喷发，早侏罗世关闭，中新生代沉积厚大碎屑岩系，伴随裂陷带的生成，演化形成许多大中型矿床。  相似文献   

国内外卡林型金矿对比研究   总被引：9，自引：0，他引：9  

普传杰  高振敏 《云南地质》2003,22(1):27-38

卡林型金矿是一种主要产于碳酸盐岩－碎悄岩建造中的微细粒浸染型金矿床，以储量大、品位低、金粒度极细为特点，主要分布于美国和中国，区域地质、成矿条件、控矿因素、矿化特征具有明显的可类比性。卡林型金矿区域成矿模式可概括为：金、汞、砷、锑等成矿元素大规模超常聚集，矿质运移－传输，矿床（矿体）的定位等三大系统（阶段）。文中亦对国内外卡林型金矿的成矿系列、成矿模式作对比研究。  相似文献   

昆阳磷矿床数字模型初步研究     

何文全 《云南地质》2001,20(1):86-94

矿床模型可为同类矿术矿产预测和找矿勘探工作提供指导，建立矿床数字模型有利于摸清矿床（体）地质参间的数学关系，掌握其相关因素间定量规律，“昆阳式磷矿床”经前人的大量工作，已成为磷矿床的找矿勘探和研究的对比标准，用数理统计工具对昆阳磷矿床部份代表性数量化相关地质因素进行初步分析，得出了一些定量关系式，可在同类矿床中有限使用，对地质勘探和矿山工作有一定的指导作用。  相似文献   

Excel软件在岩石学研究中的作图应用   总被引：1，自引：0，他引：1  

李静 《云南地质》2001,20(4):401-405

以稀土元素配分曲线图解，Q－A－P三角形图解为例，详细介绍Excel数据处理软件在岩石学研究中简单数据处理及作图方法。与用计算器及米厘纸的手工作图方法相比，大大提高了工作效率，并可根据需要在屏幕上对图件进行修饰，使用激光打印机直接输出具有出版效果的图件。也可将Excel图表插入Word文档中一起打印，插入幻灯片文稿中进行演示。  相似文献   

Priorities for basic research on permafrost     

《Quaternary Research》1975,5(1):125-150

  相似文献   

玻璃温度表的计算机视觉检定系统研究     

赖卫国 《气象与减灾研究》2002,25(3):27-32

介绍了玻璃温度表的计算机视觉检定系统的任务及软、硬件构成;并具体就温度表图像中刻度线的特征和图像识别作详细分析,以体现系统程序的关键算法思想和编辑特征;最后阐述了系统对温度表的适用范围和需进一步提高性能的方向。  相似文献   

我国地理信息系统建设及进展(1)   总被引：3，自引：0，他引：3  

黄杏元 《现代测绘》2004,27(2):3-6

GIS的基础背景和发展阶段与GIS业务化应用系统的建设两个部分，着重叙述了GIS建设的探索过程和发展思路，指出GIS建设从初步发展时期的研究实验、局部应用向着实用化、集成化和产业化方向发展，成为国民经济和社会发展普遍使用的工具，在各行各业发挥着重要的作用。同时用实例说明GIS业务化应用系统，在我国大体经历的四个发展阶段。  相似文献   

Effects of Anthropogenic Estrogens Nonylphenol and 17α‐Ethinylestradiol in Aquatic Model Ecosystems     

Burkhard A. Hense  Gabriele F. Severin  Gerd Pfister  Gerhard Welzl  Wolfgang Jaser  Karl‐Werner Schramm 《洁净——土壤、空气、水》2005,33(1):27-37

Microcosm tests were conducted to investigate the effects of the estrogenic substances nonylphenol (NP) and 17α‐ethinylestradiol (EE) on aquatic ecosystems. Maximum concentrations of 9 to 120 μg L^—1 NP resp. 49 to 724 ng L^—1 EE were induced by controlled release. The controlled release method allows the establishment of a continuous concentration course. The microcosms proved to run robustly with abiotic conditions close to natural. They developed biocenosis with similar characteristics as in natural ecosystems and, considering their given level of complexity, they can be used to describe possible risks for the environment. Both tested chemicals unveiled the potential to affect the plankton communities in the tested concentration range. NP exposure caused a reduction of Cladocera and Copepoda abundances and disturbed the phytoplankton structure. A NOEC_community of 30 μg L^—1 was calculated. In the first EE study, a flood in the lake where the microcosm water was collected caused additional stress and thereby a high variability, both between the microcosms and in each microcosm over time. Probably therefore the only effect found was a reduction of Copepoda abundance. In a second EE study Cladocera and Copepoda abundances were reduced, from which the phytoplankton benefited. Although a final interpretation is difficult for results of microcosm tests, there are indications that the found effects of EE and perhaps also NP may be caused at least partially by endocrine disruptive activity.  相似文献   

地球深部研究—地球科学发展的挑战与机遇   总被引：1，自引：1，他引：1  

马石庄 《地球物理学进展》1994,9(4):18-29

本文扼要地介绍了国际地球深部研究的发展及现状，简要地讨论了地球深部研究与地球科学相关学科的关系，力图说明及时地组织和开展地球深部研究是发展我国地球科学的新机遇，是迎接未来世纪挑战的正确选择。  相似文献