Optical Evidence of Itinerant-Localized Crossover of 4f4f Electrons in Cerium Compounds

Cerium (Ce)-based heavy-fermion materials have a characteristic double-peak structure (mid-IR peak) in the optical conductivity [$\sigma(\omega)$] spectra originating from the strong conduction ($c$)--$f$ electron hybridization. To clarify the behavior of the mid-IR peak at a low $c$-$f$ hybridization strength, we compared the $\sigma(\omega)$ spectra of the isostructural antiferromagnetic and heavy-fermion Ce compounds with the calculated unoccupied density of states and the spectra obtained from the impurity Anderson model. With decreasing $c$-$f$ hybridization intensity, the mid-IR peak shifts to the low-energy side owing to the renormalization of the unoccupied $4f$ state, but suddenly shifts to the high-energy side owing to the $f$-$f$ on-site Coulomb interaction at a slight localized side from the quantum critical point (QCP). This finding gives us information on the change in the electronic structure across QCP.Comment: 6 pages, 4 figures. To appear in JPSJ (Letters

Successful treatment for retroperitoneal cavernous hemangioma adjacent to the renal hilum via the laparoscopic approach: a case report

Introduction. Cavernous hemangiomas are common benign tumors of the skin or liver but can also rarely originate from the retroperitoneal space, especially adjacent to the renal hilum. Qualitative characterization of these retroperitoneal tumors using available imaging modalities is relatively difficult. Case presentation. A 40-year-old Japanese woman was incidentally noted to have a round homogenous tumor adjacent to the left renal hilum on computed tomography. The preoperative diagnosis was paraganglioma according to hormonal and clinical findings. The tumor was successfully resected via a laparoscopic approach, and histopathological examination of the tumor revealed cavernous hemangioma. Conclusions: Cavernous hemangioma is a rare but relatively benign disease when considering the different types of retroperitoneal tumors. We were able to effectively treat the retroperitoneal cavernous hemangioma via laparoscopy

Life cycle assessment of hydrogenated biodiesel production from waste cooking oil using the catalytic cracking and hydrogenation method.

There is a worldwide trend towards stricter control of diesel exhaust emissions, however presently, there are technical impediments to the use of FAME (fatty acid methyl esters)-type biodiesel fuel (BDF). Although hydrogenated biodiesel (HBD) is anticipated as a new diesel fuel, the environmental performance of HBD and its utilization system have not been adequately clarified. Especially when waste cooking oil is used as feedstock, not only biofuel production but also the treatment of waste cooking oil is an important function for society. A life cycle assessment (LCA), including uncertainty analysis, was conducted to determine the environmental benefits (global warming, fossil fuel consumption, urban air pollution, and acidification) of HBD produced from waste cooking oil via catalytic cracking and hydrogenation, compared with fossil-derived diesel fuel or FAME-type BDF. Combined functional unit including "treatment of waste cooking oil" and "running diesel vehicle for household waste collection" was established in the context of Kyoto city, Japan. The calculation utilized characterization, damage, and integration factors identified by LIME2, which was based on an endpoint modeling method. The results show that if diesel vehicles that comply with the new Japanese long-term emissions gas standard are commonly used in the future, the benefit of FAME-type BDF will be relatively limited. Furthermore, the scenario that introduced HBD was most effective in reducing total environmental impact, meaning that a shift from FAME-type BDF to HBD would be more beneficial