Pusan National University

About: Pusan National University is a education organization based out in Busan, South Korea. It is known for research contribution in the topics: Catalysis & Population. The organization has 24124 authors who have published 45054 publications receiving 819356 citations. The organization is also known as: Busan National University & Pusan University.

Heterogeneous Catalysis for Lithium–Sulfur Batteries: Enhanced Rate Performance by Promoting Polysulfide Fragmentations

Abstract: A spatial confiment of polysulfides using the metal compound additives having polar surfaces has been considered to be a promising approach to address the insufficient rate capability and cyclability of lithium–sulfur batteries. Herein, we report a more effective approach outperforming this conventional one: a heterogeneous catalysis to promote polysulfide fragmentations. It was revealed using combined computational and experimental approaches that an ultrastrong adsorption of elemental sulfur on TiN surfaces resulted in a spontaenous fragmentation into shorter chains of polysulfides. This heterogeneous catalysis reaction improved the sluggish kinetics of polysulfide reduction because of the chemical disproportionation at the second plateau. A markedly enhanced rate capability was finally obtained, exhibiting a discharge capacity of 700 mAh g–1 at a scan rate of 5C.

Formation of Thermoresponsive Gold Nanoparticle/PNIPAAm Hybrids by Surface-Initiated, Atom Transfer Radical Polymerization in Aqueous Media

Abstract: We investigated the formation of thermoresponsive gold nanoparticle/poly(N-isopropylacrylamde) (AuNP/ PNIPAAm) core/shell hybrid structures by surface-initiated, atom transfer radical polymerization (SI-ATRP) in aqueous media and the effect of cross-linking on the thermoresponsiveness of the AuNP/PNIPAAm hybrids. The disulfide containing an ATRP initiator was attached onto AuNPs and the monomer, NIPAAm, was polymerized from the surface of AuNPs in the absence or presence of a cross-linker, ethylene diacrylate, in aqueous media at room temperature. The resulting brush-type and cross-linked AuNP/PNIPAAm hybrids were characterized by Fourier-transform infrared spectroscopy, transmission electron microscopy, and variable temperature dynamic light scattering.

An epidemiological study of enuresis in Korean children

Abstract: Objective To estimate the prevalence of enuresis in children of elementary school age, to evaluate the impact of enuresis on these children and their parents, and to identify the methods and effectiveness of managing enuresis. Subjects and methods A randomly selected cross-sectional study was conducted in one elementary school in each urban ward (nine schools) in Pusan, Korea. The parents of these 12 570 children aged 7–12 years were asked to complete questionnaires which included items about the presence and frequency of enuresis, its perceived impact and management. Enuresis was defined as an episode of wetting occurring at least once per month. Results The overall response rate to the questionnaire was 55.8% (girls 28.2%, boys 27.6%). The prevalence of nocturnal, diurnal and combined enuresis was 9.2%, 2.2% and 1.4%, respectively. The overall prevalence of enuresis declined with age from 20.4% at 7 years old to 5.6% at 12 years old; 342 (57.0%) parents and 318 (55.6%) children were concerned about enuresis. The common self-help strategies were waking the child at night to void (38.1%) and restriction of water intake (25.7%). Of the enuretic children, only 13.7% had consulted a health worker. Conclusion The prevalence rates for enuresis in Pusan are similar to those reported from European countries. Enuretic children and their parents were moderately concerned about enuresis and the parents primarily used self-management within the family.