国际直接投资地域结构综合动因研究

本文以系统动力学思想为指导，在简要评述西方国际直接投资理论的基础上，重点研究了东道国ESP系统、投资主体OIL特征对国际生产资本地域运动的影响；指出国际直接投资地域结构形成的动力是来源于东道国、投资主体、母国的合力，提出了国际直接投资地域结构形成的综合动因理论，并建立了相关的理论模型。     

Sample preparation methods for quantitative detection of DNA by molecular assays and marine biosensors

The need for quantitative molecular methods is growing in environmental, food, and medical fields but is hindered by low and variable DNA extraction and by co-extraction of PCR inhibitors. DNA extracts from Enterococcus faecium, seawater, and seawater spiked with E. faecium and Vibrio parahaemolyticus were tested by qPCR for target recovery and inhibition. Conventional and novel methods were tested, including Synchronous Coefficient of Drag Alteration (SCODA) and lysis and purification systems used on an automated genetic sensor (the Environmental Sample Processor, ESP). Variable qPCR target recovery and inhibition were measured, significantly affecting target quantification. An aggressive lysis method that utilized chemical, enzymatic, and mechanical disruption enhanced target recovery compared to commercial kit protocols. SCODA purification did not show marked improvement over commercial spin columns. Overall, data suggested a general need to improve sample preparation and to accurately assess and account for DNA recovery and inhibition in qPCR applications.     

The role of mineralogy,geochemistry and grain size in badland development in Pisticci (Basilicata,southern Italy)

Mineralogical, geochemical and grain‐size composition of soil and pore‐water chemistry parameters were characterized on both eroded (south‐facing) and non‐eroded (north‐facing) clayey‐silt slopes in the Basilicata region (southern Italy). Only a few grain‐size parameters and clay mineralogy discriminate eroded from non‐eroded substrates. Compared with the latter, the former have fractions of over 63 µm and 1–4 µm lower and fractions 4–63 µm higher. Grain‐size characters of crusts did not discriminate with respect to substrate. Bulk rock mineralogy was not distinctive, but the clay mineral assemblage shows that the eroded slope is enriched in kaolinite, mixed layers (illite–smectite) and chlorite, whereas illite decreases, although overlaps are common. Chemical data enable discrimination between eroded and non‐eroded slopes. pH, SAR (sodium adsorption ratio), TDS (total dissolved salts) and PS (percentage of sodium) are distinctive parameters for both eroded and non‐eroded slopes. TDS increases in depth in the non‐eroded slope, whereas the maximum TDS is just below the crust in the eroded one. On average, eroded substrates are higher in pH, SAR and PS than non‐eroded ones. The ESP (exchangeable sodium percentage) of the eroded slope has a higher value than the non‐eroded one. Crusts are less dispersive than eroded substrates, and non‐eroded substrates behave as crusts. This suggests that the portion of the slope most severely exposed to weathering tends to stabilize, due to strong decreases in SAR, PS and ESP. Several diagrams reported in the literature show similarly anomalous crust samples on eroded slopes, compared with other samples coming from greater depths on eroded slopes. In the present case study, the exchangeable form of Na characterizes crusts more than the soluble form. This study describes the erosional mechanism, which involves morphological and geographic exposure and climatic elements, as well as grain size, mineralogy, chemistry and exchangeable processes of soils. Copyright © 2006 John Wiley & Sons, Ltd.     

论机检英文文献检索词的选取策略

英文文献计算机检索已发展到通过检索词匹配来实现,检索词的选取恰当与否直接影响着检全率和检准率。针对如何根据检索主题的要求及英语的语言特点,利用本专业知识、文化取向和检索知识选取英文文献计算机检索词,提出了选取英文文献计算机检索词的原则以及主题、英美语的差异等选取检索词的方法和技巧。     

Modification of the properties of salt affected soils using electrochemical treatments

In this project, an in situ soil treatment technique using the principles of electrokinetics was tested using laboratory experimental models in order to identify the potential of this approach in modifying and reinstating the physical properties of salt affected soils. Experiments were conducted in the laboratory using saline-sodic soils collected from two salt affected regions in central Victoria, Australia. Soil specimens were compacted in glass tanks to reproduce in situ density and in situ water content. Using mild steel electrodes inserted into the soil, a direct current was passed through the soil under a constant potential gradient of 0.5 V/cm for a period of 14 days. In separate experiments, distilled water and a saturated lime solution were introduced to the soil via the anode over this experimental period. It was observed that the soil dispersion, otherwise known as soil sodicity (measured as ESP—Exchangeable Sodium Percentage and SAR—Sodium Absorption Ratio) decreased by up to 90% in most regions of the soil between the electrodes. The compressive strength of the soil increased in excess of 100% with electrokinetic treatment alone while the lime-enhanced electrokinetic treatment led to an almost 200% strength increase. The liquid limit and plastic limit of the soil increased causing the plasticity index to decrease, indicating increases in soil compressive strength and workability. These results indicate the potential of this technique for improving the physical properties of salt affected soils both effectively and efficiently, and in particular gives hope for the remediation of salt affected land for infrastructure management and development.     

影响粘土胶体稳定性的因素研究

本文研究了我国六种蒙脱石及高岭石和伊利石胶体的粘度和稳定性、探讨了胶体浓度、pH值和ESP的影响及其机理。     

基于最优特征空间的震后损毁建筑物信息提取研究

基于传统面向对象方法, 提出了一种基于最优特征空间的损毁建筑物信息提取方法。 采用ESP(Estimate of Scale Parameter)工具对图像进行最优尺度分割, 之后通过选取样本, 计算各类地物距离矩阵和最小分离距离寻求最优特征空间, 最后运用最优特征空间对震后损毁建筑物影像进行提取实验, 在QuickBird影像中提取总体精度达到了83.1％, Kappa系数达到了0.813, 在无人机影像中提取总体精度为92.9％, Kappa系数达到了0.940。 本文建立的提取方法与传统分类决策树方法相比, 其提取精度和效率都有较大提高, 在损毁建筑物信息提取方面具有较好的推广价值。