Vertical velocity of the atmosphere around a floating offshore wind turbine situated in marine areas near Kaba Island, Goto City, Nagasaki Prefecture was predicted using the mesoscale meteorological model that can replicate not only ridge lift but also thermal lift. In addition, the possibility of impacts on soaring birds was investigated using vertical flow. As a result of the simulation, thermal lift and ridge lift of the area were accurately replicated. Around the coast of Kaba Island, ridge lift mainly prevailed, but almost no vertical flow was predicted above the marine waters near the wind turbine. Observations from a pre-construction survey of raptores such as ospreys and falcons revealed these birds frequently soar around the coastal areas of Kaba Island rather than in the waters where the turbine is installed, so the possibility of birds colliding with the turbine or using vertical flow from the turbine is very low.

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Bioethanol production from lignocellulosics via acetic acid fermentation is a potential way to substitute gasoline with more improved carbon utilization efficiency than the conventional alcoholic fermentation processes. Accordingly, hydrogenation of acetic acid to ethanol is a very important step to realize this acetic acid-based process. In this communication, hydrogenation mechanism of acetic acid into ethanol on a Pt catalyst supported on TiO₂ (titania) was characterized from the solvent effects. The Pt/TiO₂ catalyst was quite effective in hexane, a nonpolar solvent, to give ethanol and ethyl acetate from acetic acid in relatively high yields, while the catalytic activities were reduced in tetrahydrofuran (THF) and water, polar solvents. These results evidently support the catalytic mechanism: Ti atoms of the TiO₂ surface act as a Lewis acid to activate the carbonyl carbon of acetic acid, which leads to the efficient hydrogenation of acetic acid at the interface between Pt and TiO₂. Suppression of the ethyl acetate formation in THF and water, which could be formed via the common activated state of acetic acid on TiO₂, also supports this catalytic mechanism.

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The Fischer–Tropsch (FT) process produces versatile final products comprising diverse mixtures of various hydrocarbons, and longer chain hydrocarbon products require further refining processes to obtain the desired product fractions. The hydrocracking reaction of paraffinic hydrocarbons has been intensively investigated from the experimental and theoretical perspectives in past studies. The objective of the study is to develop an alternative hydrocracking model by introducing a production distribution matrix that allows the treatment of cracking products as individual species (i.e., no lumping required) and also by taking into account the vapor–liquid equilibrium (VLE) of the cracking reaction system with the application of Raoult’s law. Models in which the VLE was accounted for apparently produced better agreement between the experimental data and model outputs, and the use of the product distribution matrix was also effective for predicting the hydrocracking reaction. Further, the findings of this study indicated that Raoult’s law was sufficient for predicting the product compositions.

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