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Biomass burning (BB), in particular agricultural waste burning (Agri-BB), occurs at random locations, scales, and times. These factors make it challenging to detect Agri-BB accurately through satellite observations. Thus, the BB emission inventories using satellite observation data have uncertainties for their emission estimation approach and cause poor model performance for air pollutants including PM2.5. We utilized the two BB emission inventories, GFEDv4.1s and FINNv2.5 with the CMAQ model to simulate the PM2.5 heavy pollution episode in Hokkaido 2019. To estimate Agri-BB contributions, we conducted three simulation cases for each BB emission inventory: with and without Agri-BB emission, and the boosted Agri-BB emission cases. The baseline simulation failed to capture the temporal and spatial variation patterns of PM2.5. Meanwhile, the boosted Agri-BB case could show favorable performance for PM2.5 concentrations. These results indicated that the two BB emission inventories underestimated Agri-BB emissions. In the two boosted Agri-BB cases, the PM2.5 contributions from Agri-BB accounted for more than 50% during the episode. Moreover, high PM2.5 emissions were found in Northeast China and its surrounding regions similar to the two boosted Agri-BB cases. Consequently, the results revealed that Agri-BB emissions during the episode were significantly derived from the agricultural areas in Northeast China.

In this study, we investigated the growth process of M7C3 carbide by a Confocal Laser Scanning Microscope. Fe-C-Cr alloy was prepared using an arc furnace. The composition was determined to be Fe:C:Cr=55:5:40(wt%). From the results of XRD and EPMA, the Fe-C-Cr alloy contained M7C3 carbide in the internal structure. In condition of two cooling rates 60°C/min and 30°C/min observed with a Confocal Laser Scanning Microscope. Corners of the Hexagonal structure grew in the preferred orientation direction of M7C3 carbide at 60°C/min. After the growth of preferred orientation direction, the M7C3 carbide formed to connect between the corners. At a cooling rate of 30°C/min, M7C3 carbides grew in oblique direction to the observation area. At the beginning, the structures were hidden in the fluid. But the structures started to grow, the shape of the hexagon became eventually. After the melting experiment, the samples were observed by Optical Microscope and Scanning Electron Microscope. As a result, since hexagonal structure arose a difference in height between the outside and the inside. M7C3 carbides grew from the outside in the solidification process.

In 2011, the example that breakwaters collapsed because of the basic ground’s destabilization was reported by Tohoku-Kanto earthquake tsunami. Fluid-Structure-Soil coupling simulation is desired for a systematic comprehension of the breakwater collapse mechanism, and it may help to develop next disaster prevention method. In this study, A particle simulation tool based on the SPH has been modified and improved to analyze seepage flow and soil scouring. In seepage flow analysis, as a first step, this simulation treat the surface flow and seepage flow interactions by using governing equation. In the scouring analysis, soil scour is judged by an empirical criteria based on quicksand quantity formula.