Modeling of radical reactions is usually achieved by collecting many possible elementary reactions without any experimental verification. This operation excessively increases the number of differential equations, which in turn increases difficulties in the estimation of true reaction mechanisms. However, this problem may be solved by dynamic sensitivity analysis. The present work evaluates the performance of SoftCADS (Software for calculation of dynamic sensitivities) through its application to a complicated mathematical model for the oxidation of CO in vapor phase. As a result, SoftCADS is shown to easily simplify such a mathematical model through the computation of dynamic sensitivities, in which only the differential equations for reactant concentrations are given as a sole input. Also, SoftCADS allows the computation of dynamic sensitivities with high accuracy and reliability. The computation is time-costly for the original mathematical model when the reactive species are large in number and a system of the differential equations is stiff. However, after simplification of the model, the computation time is significantly shortened.

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Solubilization of nitrogen and mineral in aquacultural solid waste discharged from freshwater recirculating fish culture system was attempted by using a microwave heating system in order to use it for production of liquid fertilizer. Solubilization rates of nitrogen, phosphorus, calcium, magnesium, sodium, potassium, iron, zinc, manganese and copper were determined after digestion of solid wastes with hydrogen peroxide and sulfuric acid and microwave heating in closed Teflon vessels. The treatments of 40 or 200 mmol g^-1 solid waste (SW) of hydrogen peroxide at 125℃ were effective to elute nitrogen and magnesium and the solubilization of phosphorus, calcium, ion, zinc manganese and copper were below 10 %. However, the solubilization rates of these elements were not sufficient for the utilization. Based on the above result, digestions with 0.1, 1, and 10 mmol g^-1 SW of sulfuric acid at 175℃ were conducted after digesting with 40 mmol g^-1 SW in hydrogen peroxide. In the digestion with 10 mmol g^-1 SW of sulfuric acid, more than 80 % of quantum in all the elements dissolved out from the waste, while the digestions with lower concentrations of sulfuric acid was not be effective. The result indicates that addition of more than 40 mmol g^-1 SW of hydrogen peroxide and 10 mmol g^-1 SW of sulfuric acid was efficacious for the solubilization of solid waste.

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A field experiment on soil moisture and soil temperature was carried out to examine the effect of thermal environmental control of urban soils on the basis of two model pedons - the lawn pedon and the construction-waste pedon, which were designed from the combination of the soil quality and grading method generally used in urban parks. The lawn pedon warmed up easier and had a larger heat capacity compared to the construction-waste pedon, while heat transmission was faster in the construction-waste pedon. Soil properties and grading method effected soil moisture capacity and capillarity, which resulted in controlling soil surface temperature and heat transmission.

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