雷州半岛英峰岭剖面多期红土矿物学特征初步研究   总被引：3，自引：0，他引：3  

文国高  文启忠  朱照宇  徐义芳 《矿物岩石地球化学通报》1997,(3)

雷州半岛英峰岭剖面多期红土矿物学特征初步研究＊文国高文启忠朱照宇徐义芳（中国科学院广州地球化学研究所，广州５１０６４０）关键词多期红土矿物学红土化雷州半岛我国南方热带－亚热带广泛发育的红土（包括红色风化壳和红色古土壤），记录了形成过程环境变迁的重要信...  相似文献   

膨胀土判别与分类的灰关联分析法   总被引：13，自引：3，他引：13  

陈新民  李生林 《岩土力学》1996,17(4):30-34

基于灰色系统理论，给出一种用于膨胀土判别与分类的新方法—灰关联分析法。实际算例表明，该法具有简单方便、结果客观可靠等优点。  相似文献   

关于地基承载力的探讨   总被引：6，自引：0，他引：6  

李宝强 《岩土工程技术》2004,18(4):191-193,198

以土质地基为研究对象 ,结合载荷试验 p s曲线 ,应用土体的极限平衡理论 ,对地基土的变形性状、地基土承载力以及承载力修正等问题进行了分析。分析结果显示 :地基土承载力不单是地基土抗剪强度指标的函数 ,同时还与作用其上的基础埋深及基础宽度等因素密切相关。进行地基基础设计时 ,应根据实际的基础埋深与宽度对勘察资料中的地基土承载力进行修正 ,并提出了有关承载力修正的建议  相似文献   

长春市城市土壤中重金属元素的积累及其微生物特性研究   总被引：10，自引：2，他引：10  

刘乃瑜  马小凡  谢忠雷  郭平 《吉林大学学报(地球科学版)》2004,(Z1)

由于人为活动的影响,长春市城市土壤中重金属Cu、Zn、Pb、Cd已有了显著积累。在重金属的胁迫下,土壤微生物特征发生了明显变化,微生物代谢活动明显增强,但微生物生物量却有较大的降低。微生物生理生态参数土壤微生物量碳与总有机碳的比值(Cmic/Corg)和代谢商QCO2(微生物呼吸作用强度与微生物量碳的比值)变化异常。研究表明,微生物特性可作为城市土壤环境中重金属含量变异的有效指标。  相似文献   

石油污染对冻土热传导的影响     

Zhuravlev Igor Igorevich 《冰川冻土》2004,26(Z1):128-132

Complex experimental research of thermal properties of oil-contaminated frozen soils was carried out. On the basis of the obtained results the influence of the various factors connected with oil pollution on heat transfer in frozen soils was analyzed. And the model of heat transfer in frozen soils was offered.  相似文献   

土壤的冷生构造及其对阿拉斯加土地利用的意义     

C. L Ping  M.T. Jorgeson  Y.L. Shur 《冰川冻土》2004,26(Z1):1-7

Cryogenic structure (patterns made by ice inclusions) in seasonally frozen and permafrost-af-fected soils result from ice formation during freezing. Analysis of cryogenic structures in soils is essential to our understanding of the cryogenic processes in soils and to formulating land use management interpretations. When soils freeze, the freezing front moves downward and attracts water moving upward resulting in mainly horizontal lenticular ice formation. Platy and lenticular soil structures form between ice lenses in upper active layer. The reticular soil structure usually forms above the permafrost table caused by freeze-back of the permafrost. The upward freeze-back resulted in platy soil structure and the volume changes following the annual freeze-thaw cycle resulted in vertical cracks. The combined result is an ice-net formation with mineral soils embedded in the ice net. The upper permafrost layer that used to be a part of the active layer has an ice content exceeding 50% due to repeated freeze-thaw cycles over time. The mineral soils appear in blocks embedded in an ice matrix. The permafrost layer that never experienced the freeze-thaw cycle often consists of alternate layers of thin ice lens and frozen soils with extreme hard consistence and has relatively lower ice content than the ice-rich layer of the upper permafrost. Ice contents and thaw settling potentials associated with each cryogenic structure should be considered in engineering and land use interpretations.  相似文献   

土体冻结过程中的盐分场研究     

邴慧  何平  杨成松 《冰川冻土》2004,26(Z1):44-49

As to salty soil, salt migrates with water in freezing soils, assembles and crystallizes continuously. Consequently the swelling of the soil volume leads to the phenomenon of salt heaving. It has a practical significance for solving salt-heaving and frost-heaving damage in engineering to deepen the understanding of salt heaving mechanism. In this paper a general overview about new research results at this aspect was presented. And then the study of salt migration and salt heaving mechanism and present salt heaving models were summarized. For further researching the field of salt transfer it is urgent to continually strengthen the salt migration and the numerical simulation study of salt heaving mechanism to expect perfecting the general evaluation of salt heaving prediction models so as to have a better service for engineering.  相似文献   

非饱和土中镉离子传输模型参数反演   总被引：6，自引：0，他引：6       下载免费PDF全文

崔凯  李宝元  李兴斯  杨国伟 《水科学进展》2004,15(6):700-705

使用自行设计的的真空实验装置,采用一维实验室土柱实验方法在不同实验条件下进行了15组实验,并基于实验所得的穿透曲线,使用梯度正则化方法反演得到了镉离子在8种葡萄牙土样和1种比利时土样中相应的传输模型参数。同时通过数值模拟实验验证了梯度正则化方法的有效性和可靠性,进而证明所得结果是有效的。  相似文献   

Nickel speciation in Sebertia acuminata,a plant growing on a lateritic soil of New Caledonia     

Nicolas Perrier  Fabrice Colin  Tanguy Jaffré  Jean-Paul Ambrosi  Jérôme Rose  Jean-Yves Bottero 《Comptes Rendus Geoscience》2004,336(6):567-577

Nickel speciation in a nickel hyperaccumulating plant (Sebertia acuminata) and its associated soil of southern New Caledonia was studied using various analytical methods. The soil is formed of iron oxides (goethite, hematite), which contain almost all the nickel. The available nickel is probably linked to the organic matter in the litter. Sebertia acuminata, acts as a nickel pump, and concentrates the metal in its leaves. It partitions nickel and silica; nickel is concentrated in the cells (probably in the vacuoles) as organometallic complexes, whereas silica forms the framework of the cells, and the phytolithes. A thorough study of these plants seems essential in order to define the soil–plant relations, and to propose appropriate ways for ecological restoration. To cite this article: N. Perrier et al., C. R. Geoscience 336 (2004).  相似文献   

Effet de la teneur en eau d'un sol sur la réduction bactérienne d'oxydes de fer     

Sébastien J. Stemmler  Stéphanie Loyaux-Lawniczak  Jacques Berthelin 《Comptes Rendus Geoscience》2004,336(13):1171-1179

Iron-reducing activity of autochthonous bacteria from two temporary hydromorphic soils is evaluated by the study of iron reductive dissolution, as a function of water content. The release of ferrous iron in solution is coupled to the mineralization of soil organic carbon. Water soil saturation is not necessary for iron reductive dissolution, since the highest dissolution is obtained for a wet, but not water-saturated soil (100% of water holding capacity WHC), and dissolution is also very high in a soil at 75% WHC. To cite this article: S.J. Stemmler et al., C. R. Geoscience 336 (2004).  相似文献