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成都粘土孔隙性的微观研究 总被引：4，自引：0，他引：4
孔隙是土结构的重要标志之一,其特征对土的工程地质性质有很大影响。本文介绍了应用结构图象定量分析系统对成都粘土孔隙性的微观研究成果并对孔隙的大小、数量、形状、类型和定向程度等形态和几何特征进行了讨论。 相似文献
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在怀俄明州Ｂｉｇｈｏｒｎ盆地中的５个地区进行了地植物反射率研究，波谱测试用的是ＳＥ—５９０手提式波谱仪，采集可见光及近红外区的数据（０．４５～１．１μｍ）。这项调查结果表明，绿峰（０．５６μｍ）和红谷（０．６７μｍ）位置的大幅度蓝移（向较短波长移动）是蒿类植物中由烃引起的病变的最可靠标志。只有在蒿长在大量地表看得见或近地下烃类的地区，这种蓝移才能检测到。研究发现波谱反射率强度数据与地在或地下烃类的出现无大的相关性。 相似文献
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郯庐断裂带中段的水平形变 总被引：1，自引：0，他引：1
本文利用布设在鲁东南地区跨越郯庐断裂带中段的两期三角点成果,推求三角点位移矢量及水平应变场各项参数.结合地震地质背景对本区自1954年以来的水平形变情况进行分析。发现:郯庐断裂中段处于近东西向的压应力环境中;在本区的沂水、沂南和莒南、临沂附近积累了较大的弹性应变能,因而这一地区可能发生大地震的危险性较大。 相似文献
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An LH Zheng BH Wang LJ Zhang YQ Chen H Zhao XR Zhang L Lei K 《Marine pollution bulletin》2012,64(2):303-309
In the present study different biomarker responses and genotoxicity were determined in wild mud snails (Bullacta exarata) collected from 3 sampling sites in Bohai Bay in northeastern China, which is a region that is under considerable anthropogenic influence. Significant spatial variability of superoxide dismutase (SOD) and metallothionein (MT)-like proteins were recorded, while glutathione transferase (GST), catalase (CAT), and vitellin-like proteins (Vn's) were not observed. Furthermore, genomic DNA that was amplified with 4 fluorescence-labeled primer pairs showed variable genetic distances among the 3 wild mud snail populations found in Bohai Bay, which may be correlated with differences in the types of environmental genotoxicants, such as heavy metals and polycyclic aromatic hydrocarbons. This multi-biomarker approach provided an improved understanding of the potential toxicological impact of contaminated sediments on benthic organisms. 相似文献
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A mathematical solution for solute transport in a three-dimensional porous medium with a patch source under steady-state, uniform ground water flow conditions was developed by Domenico (1987). The solution derivation strategy used an approximate approach to solve the boundary value problem, resulting in a nonexact solution. Variations of the Domenico (1987) solution are incorporated into the software programs BIOSCREEN and BIOCHLOR, which are frequently used to evaluate subsurface contaminant transport problems. This article mathematically elucidates the error in the approximation and presents simulations that compare different versions of the Domenico (1987) solution to an exact analytical solution to demonstrate the potential error inherent in the approximate expressions. Results suggest that the accuracy of the approximate solutions is highly variable and dependent on the selection of input parameters. For solute transport in a medium-grained sand aquifer, the Domenico (1987) solution underpredicts solute concentrations along the centerline of the plume by as much as 80% depending on the case of interest. Increasing the dispersivity, time, or dimensionality of the system leads to increased error. Because more accurate exact analytical solutions exist, we suggest that the Domenico (1987) solution, and its predecessor and successor approximate solutions, need not be employed as the basis for screening tools at contaminated sites. 相似文献
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