The AIST-SHANEL (AIST-Standardized Hydrology-based AssessmeNt tool for chemical Exposure Load) software was developed to estimate detailed and accurate exposure predictions of concentrations of chemicals at watershed areas for use within chemical risk assessment and management in Japan. This software covers the area more than 50% population in Japan. The main technical focus is on the temporal and spatial fate of chemicals in surface water, together with emissions from point sources of various industry and sewage treatment plants and non-point sources of households and agricultural land. Therefore, it is necessary to account for spatial and temporal distributions in exposure concentrations of chemicals with chemical emissions and river discharge. For estimating concentrations of chemicals in surface water on the 1km scale per day or month, a given watershed area was segmented into 1km grids, including 3 compartments of surface water, sediment, surface soil. The exposure concentrations in the watershed area were predicted based on the river discharge and the emission amounts of chemicals at each grid. The discharge was estimated from precipitation amounts in the watershed area. The emission amounts of chemicals based on the PRTR in Japan were allocated to 1km grids within the watershed area using industrial manufacture data, sewerage area data and land use data. The attenuation mechanisms included advection, diffusion, sorption/desorption, settling and resuspension of suspended solids, diffusive exchange between compartments, and biodegradation. Required input parameters in this model were emission data, sewage removal rate and basic chemical-specific properties for the chemical of interest. Here this model was applied to Tama River and predicted the exposure concentrations of some representative chemicals, for example 4-nonylphenol, in terms of ecological risk and risk reduction measures. In this way, this model will enables us to conduct ecological risk assessment in aquatic systems and will be expected as chemical risk assessment tool.

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Fracture at joint-tips in a closing mode (K_I < 0), which is opposite from the opening mode (K_I > 0), is discussed upon an analysis of the pure mode I crack propagation from tips of kinked joints, taking an overall slide on the joint surface and a possible closure of the joint into consideration. The stress intensity factors {K_IB, K_IIB} at tips of kinks are accurately analyzed by the Stress Compensation-Displacement Discontinuity Method (SC-DDM), and they are successfully applied to the pure mode I crack propagation analysis, which is conditioned only by K_IIB = 0. The fracture initiation in the closing mode is evaluated by minimizing the size of kink and open-crack in the model, and it is clarified that the fracture locus in the closing mode is well described by the maximum circumferential stress criterion which is widely used to evaluate the fracture initiation in the mixed mode of the opening mode and in-plane sliding mode.

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The aim of this paper is to derive the relation between friction factor and the Reynolds number for the pseudo-plastic fluid flow in concentric annular tubes with roughness, which is assumed the model of drilling mud flow in a well, because the estimation methods of the friction factor in the fluid flow are needed.
Based on the estimation methods of the friction factor of Newtonian fluid flow in a circular tube with roughness given by Colebrook and the relation between friction factor and the Reynolds number for the pseudo-plastic fluid flow in a circular tube with smooth wall given by Dodge and Metzner, the relation between friction factor and the Reynolds number for the pseudo-plastic fluid flow in concentric annular tubes with roughness, is obtained as Eq.(21) that is capable of calculating the friction factor in the turbulent flow region of pseudo-plastic fluids in concentric annular tubes with roughness at any values of rheology parameter, relative roughness and Reynolds number by using the subroutine subprogram shown in the appendix.
The relation presented here includes the cases of Newtonian fluid and pseudo-plastic fluid flow in the circular tubes.

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Waste gypsum from construction materials have to be recycled legally in Japan. The waste gypsum contains CaSO₄ and other materials such as papers. And thus it is impossible to reuse them directly as a CaSO₄ resource. A treatment at higher reaction temperature seems to be suitable for recycling a large quantity of the gypsum. However, CaSO₄ is rather stable even at high temperature, therefore cost-intensive reactants are necessary.
Re-generation of CaO or CaS from CaSO₄ was investigated using waste plastics, which were considered as reduction agent. Thermodynamic simulation was employed to find optimal conditions for reduction of CaSO₄. Reduction experiments were conducted using reagents of CaSO₄ and polyethylene. CaO was formed from CaSO₄ and polyethylene mixture over 1273K in air. Crystal water of CaSO₄ accelerates the reaction forming CaO. Plastics can be successfully used to produce CaO and CaS from CaSO₄ in controlled atmosphere.

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