Polyacrylonitrile (PAN) electrospinning in combination with sol-gel method has been a common technique to produce inorganic nanoparticles containing composite carbon nanofibers (CNFs) for diverse applications. To investigate the morphology evolution and crystal transformation of inorganic components along with CNF formation, bioactive glass (BG) containing CNFs (CNF/BG) were prepared by sintering as-spun PAN/precursor composite nanofibers in a nitrogen atmosphere at temperatures of 800, 1000 and 1200 C. Comprehensive characterizations were performed with TEM, SEM-EDXA and XRD. For samples sintered at 800 C, numerous BG nanoparticles were observed inside the CNFs and mainly in an amorphous state. With the sintering temperature raised to 1000 C, a number of spherical BG nanoparticles were detected on the surface of the resulting CNFs, with a crystal structure of wollastonite (b-CaSiO 3 ) polycrystals. When the samples were sintered at 1200 C, the BG nanoparticles on the surface of CNFs merged into forms with cuboid-like geometry, mainly consisting of pseudowollastonite (Ca 3 (Si 3 O 9 )) single crystals. Based on the geometry evolution and dynamic size distribution function analyses (Ostwald ripening and Smoluchowski equations), it was concluded that the growth of BG nanoparticles conformed to the ripening mechanism at 800 C and migrationcoalescence mechanism at 1200 C, while the process involved both ripening and migrationcoalescence mechanisms at 1000 C.

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• Longer delayed MRI plays an important role in the diagnosis of SNNL. • Characteristic imaging feature of SNNL is pronounced peripheral enhancement with internal hypointensity. • Periphery wash-out time can differentiate SNNL from mimic diseases. • Imaging findings of SNNL on routine CT and MRI are unspecific.

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A simple electrochemical sensor has been developed for highly sensitive detection of octopamine and tyramine by electrodepositing reduced graphene oxide (ERGO) nanosheets onto the surface of a glassy carbon electrode (GCE). The electrocatalytic oxidation of octopamine and tyramine is individually investigated at the surface of the ERGO modified glassy carbon electrode (ERGO/GCE) by using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Several essential factors including the deposition cycle of reduced graphene oxide nanosheets and the pH of the running buffer were investigated in order to determine the optimum conditions. Furthermore, the sensor was applied to the quantification of octopamine and tyramine by DPV in the concentration ranges from 0.5 to 40 μM and 0.1 to 25 μM, respectively. In addition, the limits of detection of octopamine and tyramine were calculated to be 0.1 μM and 0.03 μM (S/N = 3), respectively. The sensor showed good reproducibility, selectivity and stability. Finally, the sensor successfully detected octopamine and tyramine in commercially available beer with satisfactory recovery ranges which were 98.5%–104.7% and 102.2%–103.1%, respectively. These results indicate the ERGO/GCE based sensor is suitable for the detection of octopamine and tyramine.