Experimental study on liquefaction mechanism by means of micro-mechanical method.

本研究的目的是发展改进的测量方法和预测模型对环境影响化学品的运输和命运。主要研究成果可分为以下6个部分。利用最小的测量时间、化学物质和土壤来测量化学物质迁移和阻滞的新方法：基于高效液相色谱（HPLC）的土壤微柱测量多种环境影响化学物质的迁移和吸附的方法已经开发出来。测定和预测未扰动土壤中水溶化学物质扩散输移的改进方法：一种称为未扰动半细胞法的新方法，用于测定未扰动土壤中的溶质扩散系数，并在不同的日本和欧洲土壤中进行了验证。在未受干扰和大孔土壤中吸附化学物质的重要运输过程的鉴定：小土壤颗粒和有机大分子已被证明是可移动的，并且能够作为吸附化学物质的载体。这种颗粒结合的化学物质运输可以导致化学物质和营养物质通过土壤的强化淋滤。关于非饱和土壤系统中主要化学吸附和扩散过程的新认识：建立了一种挥发性有机化学物质的综合运输-命运模型，涵盖了水相和气相化学扩散、化学蒸气吸附和疏水化学吸附。确定化学命运过程之间的联系，包括吸附时间依赖性，内部扩散和生物降解：农药和多环芳烃（PAHs）的吸附已经进行了研究。基于内部扩散概念，提出了改进的吸附-解吸非奇点（滞后）和吸附时间依赖性（动力学）的概念模型。改进的、依赖于土壤类型的模型来预测土壤气相中的主要输送参数：已经开发了新的模型来预测土壤中的气体扩散率和气体渗透性，作为土壤含水量和土壤类型（包括孔隙大小分布参数）的函数，并成功地对50多个日本和欧洲土壤的数据进行了验证。少

The purpose of this research is to develop improved measurement methods and prediction models for transport and fate of environmental impact chemicals. The major research accomplishments can be grouped into 6 sections as follows.1. New method for measuring chemical transport and retardation using minimal amounts of measurement time, chemical and soil : High Performance Liquid Chromatography (HPLC) based soil micro-column methods for measuring the transport and sorption of multiple environmental impact chemicals have been developed.2. Improved methods for measuring and predicting diffusive transport of water-dissolved chemicals in undisturbed soil : A new method, called the undisturbed half-cell (UHC) method, for measuring the solute diffusion coefficient in undisturbed soil has been developed and verified for different Japanese and European soils.3. Identification of important transport processes for adsorbing chemicals in undisturbed and macro-porous soils : Small soil particles and o … More rganic macromolecules have been shown to be mobile and able to act as carriers for adsorbed chemicals. Such particle-bound chemical transport can cause enhanced leaching of chemicals and nutrients through the soil.4. New knowledge on the main chemical adsorption and diffusion processes in unsaturated soil systems : A comprehensive transport-fate model for a volatile organic chemical, covering both water-phase and air-phase chemical diffusion, chemical vapor sorption and hydrophobic chemical sorption, has been developed.5. Identification of links between chemical fate processes including sorption time-dependency, internal diffusion and biodegradation : Sorption of pesticides and polycyclic aromatic hydrocarbons (PAHs) has been investigated. Improved conceptual models for adsorption-desorption non-singularity (hysteresis) and sorption time-dependency (kinetics), based on internal diffusion concepts, have been proposed.6. Improved, soil type dependent models to predict the major transport parameters in the soil air phase : New models to predict gas diffusivity and gas permeability in soils, as a function of soil-water content and soil type (including pore size distribution parameters), have been developed and successfully verified against data for more than 50 Japanese and European soils. Less