Hollow tin dioxide (SnO2) microspheres were synthesized by the simple heat treatment of a mixture composed of tin(IV) tetrachloride pentahydrate (SnCl4·5H2O) and resorcinol–formaldehyde gel (RF gel). Because hollow structures were formed during the heat treatment, the pre‐formation of template and the adsorption of target precursor on template are unnecessary in the current method, leading to simplified synthetic procedures and facilitating mass production. Field‐emission scanning electron microscopy (FE‐SEM) images showed 1.7–2.5 μm sized hollow spherical particles. Transmission electron microscopy (TEM) images showed that the produced spherical particles are composed of a hollow inner cavity and thin outer shell. When the hollow SnO2 microspheres were used as a lithium‐battery anode, they exhibited extraordinarily high discharge capacities and coulombic efficiency. The reported synthetic procedure is straightforward and inexpensive, and consequently can be readily adopted to produce large quantities of hollow SnO2 microspheres. This straightforward approach can be extended for the synthesis of other hollow microspheres including those obtained from ZrO2 and ZrO2/CeO2 solid solutions.

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Dedicated to Professor Ki-Jun Lee on the occasion of his retirementSince the discovery of carbon nanotubes by Iijima in 1991, [1] nanostructured carbon materials [2] have attracted tremendous attention for their possible applications in electron field emitters, catalytic supports, nanocomposites, quantum electronic devices, and electrode materials.[3]

The origin of the excellent electrocatalytic performance of PtRu alloy catalysts supported on newly synthesized carbon nanocoil supports was investigated. Among three commercially available carbon materialsVulcan XC-72, multiwall carbon nanotube, and activated carbon, the Vulcan XC-72-supported catalyst exhibited the best catalytic performance. Carbon nanocoils with variable surface areas and crystallinity were employed as the supports for 60 wt % Pt/Ru (1:1) catalysts. The catalysts supported on all these three carbon nanocoils exhibited better electrocatalytic performance compared to the catalyst supported on Vulcan XC-72 carbon. In particular, the PtRu alloy catalyst supported on CNC-2, which has both good crystallinity and a large surface area, showed a superior electrocatalytic performance, compared to the catalysts supported on CNC-1 and CNC-3 carbons.

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Although the incidence of bleeding complications during extracorporeal membrane oxygenator (ECMO) support has decreased in various trials, bleeding is still the most fatal complication. We investigated the ideal dosage and efficacy of nafamostat mesilate for use with ECMO in patients with acute cardiac or respiratory failure. We assessed 73 consecutive patients who received ECMO due to acute cardiac or respiratory failure between January 2006 and December 2009. To evaluate the efficacy of nafamostat mesilate, we divided the patients into 2 groups according to the anticoagulants used during ECMO support. All patients of nafamostat mesilate group were male with a mean age of 49.2 yr. Six, 3, 5, and 3 patients were diagnosed with acute myocardial infarction, cardiac arrest, septic shock, and acute respiratory distress syndrome, respectively. The mean dosage of nafamostat mesilate was 0.64 mg/kg/hr, and the mean duration of ECMO was 270.7 hr. The daily volume of transfused packed red blood cells, fresh frozen plasma, and cryoprecipitate and the number of complications related to hemorrhage and thrombosis was lower in the nafamostat mesilate group than in the heparin group. Nafamostat mesilate should be considered as an alternative anticoagulant to heparin to reduce bleeding complications during ECMO.