Hwang, Gi Byoung Park, Hyun-Seol Bae, Gwi-Nam Jung, Jae Hee 2024-01-20T10:03:40Z 2024-01-20T10:03:40Z 2021-08-31 2014-04 1680-8584 https://pubs.kist.re.kr/handle/201004/126975 We investigated the effects of a surrounding electric field (EF) on the performance of antimicrobial air filters coated with natural-product nanoparticles. The filtration efficiency of the control filter increased with increasing EF strength, whereas the filtration efficiency of the antimicrobial filter did not, probably because its original efficiency was already high (> 99%) and non- or relatively weakly charged bacterial aerosols were hardly affected by EF strength. The bacterial deposition profiles through the depth of the antimicrobial filters were evaluated. The bacterial concentration at depths of 0-68 mu m was increased by about 30% at an EF of 7.7 kV/cm compared with the concentration at 0 kV/cm. Scanning electron microscopy revealed that at 7.7 kV/cm, but not at 0 kV/cm, the bacteria formed dendrites on the fibers of the filter, and the concentration of bacteria deposited on the fibers at 7.7 kV/cm was two to three times that at 0 kV/cm. In antimicrobial tests, the performance of the antimicrobial filters increased with increasing concentration of antimicrobial nanoparticles, but the effectiveness differed between 0 and 7.7 kV/cm. At an identical nanoparticle concentration, the inactivation efficiency of the antimicrobial filter at 7.7 kV/cm was at most 23% lower than that at 0 kV/cm, because the relative increase in bacterial concentration and dendrite formation in the first layer of the antimicrobial filter at 7.7 kV/cm reduced the surface contact area between the bacteria and the antimicrobial nanoparticles. This study provides valuable information for developing a hybrid air purification system that serves various functions and can be used in an indoor environment. English TAIWAN ASSOC AEROSOL RES-TAAR UNIPOLAR ION EMISSION AEROSOL-PARTICLES ESCHERICHIA-COLI ELECTROSTATIC PRECIPITATORS DENDRITIC DEPOSITION SOPHORA-FLAVESCENS SILVER NANOPARTICLES CYLINDRICAL FIBER FIBROUS FILTERS THERMAL-ENERGY Effects of Electric Field Strength on an Antimicrobial Air Filter Article 10.4209/aaqr.2013.06.0199 1 AEROSOL AND AIR QUALITY RESEARCH, v.14, no.3, pp.1028 - 1037 AEROSOL AND AIR QUALITY RESEARCH 14 3 1028 1037 scie scopus 000333743900039 2-s2.0-84897851017 Environmental Sciences Environmental Sciences & Ecology Article UNIPOLAR ION EMISSION AEROSOL-PARTICLES ESCHERICHIA-COLI ELECTROSTATIC PRECIPITATORS DENDRITIC DEPOSITION SOPHORA-FLAVESCENS SILVER NANOPARTICLES CYLINDRICAL FIBER FIBROUS FILTERS THERMAL-ENERGY Electric field (EF) Bacteria aerosol Antimicrobial filter Deposition profile in filter