Abstract:Hydrogen is a promising energy carrier in the clean energy systems currently being developed. However, its effectiveness in mitigating greenhouse gas (GHG) emissions requires conducting a lifecycle analysis of the process by which hydrogen is produced and supplied. This study focuses on the hydrogen for the transport sector, in particular renewable hydrogen that is produced from wind-or solar PV-powered electrolysis. A life cycle inventory analysis is conducted to evaluate the Well-to-Tank (WtT) GHG emissions from various renewable hydrogen supply chains. The stages of the supply chains include hydrogen being produced overseas, converted into a transportable hydrogen carrier (liquid hydrogen or methylcyclohexane), imported to Japan by sea, distributed to hydrogen filling stations, restored from the hydrogen carrier to hydrogen and filled into fuel cell vehicles. For comparison, an analysis is also carried out with hydrogen produced by steam reforming of natural gas. Foreground data related to the hydrogen supply chains are collected by literature surveys and the Japanese life cycle inventory database is used as the background data. The analysis results indicate that some of renewable hydrogen supply chains using liquid hydrogen exhibited significantly lower WtT GHG emissions than those of a supply chain of hydrogen produced by reforming of natural gas. A significant piece of the work is to consider the impacts of variations in the energy and material inputs by performing a probabilistic uncertainty analysis. This suggests that the production of renewable hydrogen, its liquefaction, the dehydrogenation of methylcyclohexane and the compression of hydrogen at the filling station are the GHG-intensive stages in the target supply chains.
A total of 132 Streptococcus pneumoniae isolates collected between 2005 and 2006 in Japan were examined for susceptibility to telithromycin (TEL) and macrolide. The overall resistance to macrolide was 80%. Among the isolates, 128 strains had low-level TEL susceptibility (minimal inhibitory concentrations [MICs] 0.03-1 microg mL(-1)), suggesting that pneumococci with reduced susceptibility to TEL have appeared without prior exposure to the drug, although none of the isolates were assigned as TEL-resistant (breakpoint, > or = 4 microg mL(-1)). Eight of these isolates (MIC 0.5-1 microg mL(-1)) were analyzed for macrolide resistance determinants and genetic relatedness. They all carried mefE-mel, which encodes the macrolide efflux genetic assembly, and three also harbored ermB, which encodes rRNA methylase. Allele replacement mutagenesis of the corresponding genes in the clinical isolates revealed that reduced TEL susceptibility (MIC 1 microg mL(-1)) in S. pneumoniae may be caused by acquisition of the mefE-mel element only and additionally conferred by the ermB determinant.
This study estimated the economic effect of utilizing woody biomass as a raw material for high value-added (HVA) material products such as master batch of cellulose Nanofiber (CNF-MB) and high standard Chip-dust (HSD) in Maniwa, Japan. In order to analyze the economic effects, two scenarios were described and compared: the BAU scenario and the HVA scenario. The results show that utilizing woody biomass for manufacturing material products can increase the net benefits to businesses as well as stimulate the economic ripple effect and job creation in a local region such as Maniwa. Moreover, the effects of HVA products can be greater than those for the four kinds of existing products. These results could help clarify the effectiveness of utilizing woody biomass in material products as a method to promote woody biomass business and regional development.
✜ Abstract:In the face of increasing demand for woody biomass, mill residues continue being used more frequently than logging residues in Japan because of their relative ease of use.The Japanese government set a target ratio of logging residue use to 30 percent by 2030 compared with less than 1 percent in 2009. This study examined GHG emissions and the economic effects of logging and mill residues, which are employed as raw materials for various purposes in Maniwa, Japan.In 2012, 23,710 tonnes of woody biomass resources were collected and used in Maniwa, of which roughly 79 percent were logging residues. These resources are manufactured into several types of wood products, such as chips, bark, and chip dust. The manufactured products are then transported and consumed for paper, poultry litter, and fuel. Based on this, three scenarios were organized by changing the type of woody biomass resource use as follows: the business-as-usual (BAU) scenario, the logging-residues-only utilization (LRU) scenario, and the mill-residues-only utilization (MRU) scenario. Under the LRU scenario, the expected regional effect is almost 188 million JPY, whereas the MRU scenario achieves almost 20 times more financial benefits than the LRU scenario with the integrated woody biomass station. However, approximately 13 full-time jobs can be created under the LRU scenario, which is 1.6 times higher than the 6 jobs created under the MRU scenario. In terms of GHG emissions, the LRU scenario can reduce GHG emissions by up to roughly 211t CO2eq/t compared to the MRU scenario.Overall, the promotion of logging residue use for manufacturing wood products has significant advantages over mill residues in both the reduction of GHG emissions and the growth of regional economies.
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