Chonbuk National University

About: Chonbuk National University is a education organization based out in Jeonju, South Korea. It is known for research contribution in the topics: Apoptosis & Graphene. The organization has 14820 authors who have published 28884 publications receiving 554131 citations.

Ultrahigh-temperature metamorphism followed by two-stage decompression of garnet–orthopyroxene–sillimanite granulites from Ganguvarpatti, Madurai block, southern India

Abstract: The Mg–Al granulites from Ganguvarpatti consist of orthopyroxene–sillimanite–garnet ± quartz as peak assemblage, with a few porphyroblasts of cordierite and sapphirine. These assemblages were strongly overprinted by late symplectites and coronas. Orthopyroxene inclusions in garnet and porphyroblast cores have the highest X Mg (0.80) and Al2O3 content (10.7 wt%). The estimated near-peak metamorphic conditions (1,000±50°C and 11 kbar) using garnet–orthopyroxene geothermobarometry are consistent with those determined using a petrogenetic grid. The proposed multi-stage evolution process implies an initial decompression, deduced from multi-phase symplectites, followed by cooling during biotite formation. Further late decompression is explained from the orthopyroxene rims on biotite. This proposed P–T path thus suggests a unique and complex evolution history for the UHT granulites of southern India. Present results are comparable with similar adjacent terranes in the Gondwana supercontinent, but the lack of structural and geochronological data makes a link with any major metamorphic event uncertain.

Hepatic Arterioportal Shunts: Dynamic CT and MR Features

Abstract: With the increased temporal resolution available in dynamic computed tomography (CT) and magnetic resonance imaging (MRI), hepatic arterioportal shunts are now more frequently encountered than in the past. The condition occurs in various hepatic diseases in which portal or hepatic venous flow is compromised. The underlying mechanism and the degree of shunt affect its appearance at dynamic imaging. The dynamic CT and MRI findings have been summarized as early enhancement of peripheral portal veins, and wedge-shaped transient parenchymal enhancement during the hepatic arterial phase. Recognition of arterioportal shunt can suggest the presence of a previously unsuspected disorder and avoids false-positive diagnosis or overestimation of a hepatic disease. Familiarity with the pathophysiology of arterioportal shunt also allows investigation of the hepatic hemodynamic changes occurring in various hepatic diseases.

Hollow carbon nanofibers as an effective electrode for brackish water desalination using the capacitive deionization process

Abstract: Capacitive deionization (CDI) is strongly recommended as an environmentally friendly and economical technique for removing salt ions from saline water. In this study, highly efficient hollow carbon nanofiber electrodes for capacitive deionization were prepared using co-axial electrospinning of poly(methyl methacrylate) (core) and poly(acrylonitrile) (shell) polymer solutions, followed by oxidative stabilization and then carbonization. The morphology, pore structure and electrochemical performance were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), nitrogen adsorption–desorption isotherms, and cyclic voltammetry, respectively. The synthesized hollow carbon nanofibers had a specific capacitance of 222.3 F g−1, which is almost 4 times higher than the corresponding value for solid carbon nanofibers (63 F g−1). Moreover, the surface area of the hollow nanofibers (186 m2 g−1) was 10 times greater compared to the surface area of solid carbon nanofibers (17.7 m2 g−1). Accordingly, the salt ion electrosorption capacity of the modified carbon nanofibers was greatly enhanced; the hollow nanofibers exhibited an excellent desalination performance (∼86%) and a better cycling ability. These properties are attributed to the hollow structure. Overall, the proposed modification to carbon nanofibers makes them adequate not only for use as promising electrodes for the CDI process but also for any application requiring carbonaceous materials with a high specific surface area.