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To mitigate climate change, individual greenhouse gas emissions need to decline substantially. This paper empirically explores the relationship between individual carbon footprints and carbon literacy as well as socio-economic and attitudinal factors. To operationalize carbon literacy, we distinguish between carbon knowledge and carbon engagement. Our econometric analysis uses widely representative survey data for 1000 individuals in Germany and distinguishes between components of an aggregate carbon footprint and of carbon footprints related with electricity consumption, heating, motorized individual transport, aviation, and dietary choices. We find a negative and sizeable correlation between carbon engagement and the aggregate footprint, as well as the footprints related to electricity consumption and diet. For example, a one-unit increase in our index reflecting carbon engagement corresponds to a decrease in the aggregate carbon footprint of about 4%. Furthermore, for carbon knowledge we find a negative correlation with the carbon footprint from diet. We also find significant correlations between the carbon footprints and gender, age, income, education, environmental preferences, and policy orientation, which generally exhibit the intuitively expected signs, but differ somewhat across activities. Overall, our findings support the notion that fostering carbon engagement represents a more effective strategy for reducing individuals' carbon footprints than enhancing carbon knowledge.

Bacterial contamination causes yield reduction during ethanol production from molasses. To prevent contamination, construction of a fermentation system using acetate-tolerant yeast under an acetate-containing condition was attempted. Schizosaccharomyces pombe was screened as an acetate-tolerant strain. Bacterial contamination was significantly prevented by the combined use of Sc. pombe and acetate.

AbstractSemi‐natural mountain grasslands are increasingly exposed to environmental stress under climate change. However, which are the environmental factors that limit plants in these grasslands? Also, is the present management effective against these changes? Fitness‐related functional traits may offer a way to detect changes in performance and provide new insights into their vulnerability to climate change. We investigated changes in performance and variability of functional traits of the mountain grassland target species Arnica montana along a climate gradient in Central German low mountain ranges. This gradient represents at its lower end climate conditions that are expected at its upper end under future climate change. We measured vegetative, generative, and physiological traits to account for multiple ways of plant responses to the environment. Using mixed effects and multivariate models, we evaluated changes in trait values among individuals as well as the variability of their populations in order to assess performance under changing summer aridity and different management regimes. Fitness‐related performance of most traits showed strongly positive associations with reduced summer aridity at higher elevations, while only specific leaf area and leaf dry matter content showed no association. This suggests a higher performance level at less arid montane sites and that the physiological traits are less sensitive to this climate change factor. The coefficient of variation of almost all traits declined steadily with decreasing site aridity. We suggest that this reduced variability indicates a lower environmental stress level for A. montana toward its environmental optimum at montane elevations, especially because the trait performance increased simultaneously. Surprisingly, management factors and habitat characteristics had only low influence on both trait performance and variability. In summary, summer aridity had a stronger effect to shape the trait performance and variability of A. montana under increased environmental stress than management and other habitat characteristics.

Abstract The performance of a multi-level overtopping wave energy converter has been numerically investigated in a three-dimensional wave tank. The device has three extra slots and is positioned on a breakwater. The span length of the breakwater is the main parameter associated with the three-dimensional effects on the hydraulic efficiency of the wave energy device. It has been shown that the device with a finite span yields a lower captured crest energy due to waves falling-down the edges during the run-up process. The result also implies that as the span of the device is increased, the efficiency tends to increase further to resemble the two-dimensional device. The three-dimensional mechanism has a significant influence on the potential energy in the water being stored by the higher reservoirs, while that of lower ones have relatively smaller effects. In addition, a relation between hydraulic efficiencies of two and three-dimensional devices has been proposed.

Transesterification of alkyl esters plays an important role in biodiesel production, and a critical substance in this mechanism is triacylglycerol. A molecular modeling technique is used in this study to determine the geometrical parmeters of triacylglycerol via semi-empirical AM1, PM3 and ab initio HF/6-31G with the GaussView 03W and GAUSSAIN 03W pieces of software. The results obtained from these three models showed that the geometrical parameters of the triacylglycerol molecules are in the same range. Hence, these molecular models can be used in the simulation of the transesterification mechanism. There are six possible mechanisms for the biodiesel transesterifications. Each type of mechanism contains six reaction steps. Using the B3LYP/6-31G//PM3 method, the transesterification mechanism was simulated to determine the best possible pathway.

In 2021, 56% of the global population lived in cities, and by 2050 the ratio of urban-to-rural population is expected to reach 67% [...]

This work focused on the conversion of crude palm kernel oil (CPKO) to biojet fuel via deoxygenation reaction in a fixed bed reactor. The catalyst was Pt supported on activated carbon (Pt/C). The investigation involved the effects of various operating parameters such as reaction temperature (350–420 °C), pressure (250 and 500 psi), flow rate of CPKO (0.02 and 0.04 mL/min), flow rate of hydrogen (17.5, 35.0, and 70.0 mL/min), and the amount of catalyst (0.05 and 0.07 g) on the reaction performance and the fuel properties of product. The biojet yield of 58.29%, with the major content of linear alkane in the range of jet fuel (nC8-nC16) of 27.68% and the productivity of 9.32 g product/g catalyst·h were achieved at the optimal operating conditions (420 °C, 500 psi, CPKO flow rate at 0.02 mL/min, hydrogen flow rate at 17.50 mL/min (H2-to-CPKO molar ratio of 28.02), and 0.07 g of Pt/C catalyst). The oxygen content was reduced from 18.83% (in CPKO) to 14.96% (in the product). To improve the freezing point of biojet fuel via cracking and aromatization, the catalyst bed was modified by adding HZSM-5 as a catalyst bed adjacent to the bed of Pt/C. The freezing point of product was significantly lowered by 30 °C.