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Biodiesel could be produced from triglycerides and dimethyl carbonate, instead of the conventional methanol, in this non-catalytic supercritical dimethyl carbonate method. It was demonstrated that, supercritical dimethyl carbonate method successfully converted triglycerides as well as fatty acids to fatty acid methyl esters (FAME) with glycerol carbonate, a higher value by-product compared to the conventional glycerol. The FAME are high in yield, comparable with supercritical methanol method, and satisfy the international standard for use as biodiesel fuel. In this study, therefore, optimization of supercritical dimethyl carbonate method was discussed to include all important key parameters such as reaction temperature, pressure, time, molar ratio of dimethyl carbonate to oil, the FAME yield, thermal decomposition, degree of denaturation, tocopherol content, oxidation stability and fuel properties. The optimum condition for supercritical dimethyl carbonate method was determined at 300 °C/20 MPa/20 min/42:1 molar ratio of dimethyl carbonate to oil to have satisfactory yield of FAME at 97.4 wt%. Conclusively, this study showed the importance to address all those key parameters in order to produce high quality biodiesel from supercritical dimethyl carbonate method.

This review summarizes the use of ionic liquids in Na secondary batteries and discusses their electrochemical performance with various electrode materials.

Can shrinking cities harness population decline to improve their sustainability by repurposing land use, for example, for localizing food production? Whether such a transition is feasible depends on the pre-shrinkage state of urban agricultural land use, including ongoing trends in local land use change. This study examined agricultural land use from 2007–2017 in Kyoto City, Japan. Kyoto is on the brink of a large projected population decline (~190,000 or ~13% until 2040) and serves as a representative for a large number of regional Japanese cities in a similar situation. Analysis was based on a public 2007 land use data set, aerial and satellite imagery and ground truthing. Results showed a decline of 209 ha or 10% in agricultural land use over ten years, but also highlight the diversity of ongoing agricultural land use types not captured by standard categories. The main post-agricultural land uses were residential (40%) and vacant land (28%). These results have implications for planning and policy. Kyoto City is currently not set to benefit from the projected shrinking process through localizing food production, despite a tradition of vegetable production. Future research should analyze drivers of change for observed agricultural land use.

As Earth’s climate has varied strongly through geological time, studying the impacts of past climate change on biodiversity helps to understand the risks from future climate change. However, it remains unclear how paleoclimate shapes spatial variation in biodiversity. Here, we assessed the influence of Quaternary climate change on spatial dissimilarity in taxonomic, phylogenetic, and functional composition among neighboring 200-kilometer cells (beta-diversity) for angiosperm trees worldwide. We found that larger glacial-interglacial temperature change was strongly associated with lower spatial turnover (species replacements) and higher nestedness (richness changes) components of beta-diversity across all three biodiversity facets. Moreover, phylogenetic and functional turnover was lower and nestedness higher than random expectations based on taxonomic beta-diversity in regions that experienced large temperature change, reflecting phylogenetically and functionally selective processes in species replacement, extinction, and colonization during glacial-interglacial oscillations. Our results suggest that future human-driven climate change could cause local homogenization and reduction in taxonomic, phylogenetic, and functional diversity of angiosperm trees worldwide.

固気二相流中の粒子の粒径分布の計測は, 燃焼装置から排出される粒子状物質の性状評価などにおいて, 極めて重要な操作である.従来の測定法では, 複雑な構造を持つ分級器を用いねばならず, 煩雑な操作が必要となる.著者らは, 簡易な粒径分布測定法として, 逆向きサンプリング時の粒子の分級効果を利用した新しい手法を考案した.しかし, 逆向きサンプリング時の粒子の分級効果については, 検討例が極めて少なく, 分級効率の評価式も作成されていない.本研究においては, まず, 逆向きサンプリング時のプローブ周辺の粒子挙動を数値解析し, 分級効率に及ぼす, 粒子慣性力や吸引流速などの影響を評価した.さらに, 微粉炭および灯油燃焼時のダストを用いて, 分級効率に関する実験を行い, 数値解析の妥当性を評価した.これらより, 逆向きサンプリング時の分級効率は, 慣性パラメータの増加に対して指数関数的に減少し, その減少傾向は吸引流速の増加に対して緩やかになることなとを明らかにし, 分級効率とこれらのパラメータの間の関係を表す評価式を導出した.

The Smart Grid is a novel concept which integrates the power grid and the information-communication technology in order to increase the reliability of electricity and the efficiency of energy usage...