Article
Engineering, Chemical
Juan Fernandez de la Mora, Steven Papanu
Summary: We have used improved PSL particle synthesis methods and high-resolution DMAs to successfully synthesize similar to 200 nm PSL spheres with unusually narrow mobility distributions, achieving FWHM as small as 1/60. We have also synthesized and analyzed PSL particles with diameters of about 300 nm, reaching FWHM as small as 1/80, comparable to the narrowest mobility peaks observed in viral particles studied with high-resolution DMAs. The electrosprayed 300 nm particles produced two distinguishable peaks, with the least mobile one being an artifact of the electrospraying or charge reduction process. Future improvements in PSL synthesis are expected to yield particles with mobility peaks having FWHM as small as 1/100.
JOURNAL OF AEROSOL SCIENCE
(2023)
Article
Engineering, Chemical
Juan Fernandez de la Mora
Summary: The Half-Mini Differential Mobility Analyzer (HM-DMA) developed in our laboratory can classify particles smaller than 10 nm with high resolution and theoretically up to 30 nm. Tests were conducted using 38 nm particles from the Chronic Bee Paralysis Virus (CBPV), which showed a narrow mobility distribution with FWHM<2%. The HM-DMA was able to resolve these particles with a resolving power of over 20.
JOURNAL OF AEROSOL SCIENCE
(2023)
Article
Engineering, Chemical
Eungchul Kim, Jaewon Lee, Younghun Park, Cheolmin Shin, Jichul Yang, Taesung Kim
Summary: The shape of fumed silica aggregates has an impact on CMP performance, with different proportions of linear and spheroidal aggregates affecting the outcome. The distribution and quantity of contact bumps from bumpy abrasives can explain the results of CMP, and a mixture of spherical and non-spherical abrasives in specific ratios can improve CMP performance.
Article
Engineering, Chemical
Luis Javier Perez-Lorenzo, Juan Fernandez de la Mora
Summary: A DMA designed for high resolution viral particle analysis has been modified to improve gas flow laminarization, leading to more accurate analysis of viral particles. Experimental tests have been conducted at different flow rates to validate the performance of the DMA under varying conditions.
JOURNAL OF AEROSOL SCIENCE
(2021)
Article
Thermodynamics
Christian Axt, Anna Massmeyer, Stefan Pielsticker, Reinhold Kneer
Summary: The formation of inhalable fine particles is a harmful side effect of solid fuel combustion processes, and understanding this process is crucial for environmental protection. Previous studies focused on simplified laminar combustion conditions, while the behavior of turbulent flame structures in real industrial applications remains poorly understood. This study developed a test rig to investigate particulate matter formation and found that local differences play a significant role in particulate matter formation.
COMBUSTION AND FLAME
(2022)
Article
Thermodynamics
B. Rossomando, E. Meloni, G. De Falco, M. Sirignano, I Arsie, V Palma
Summary: A detailed experimental characterization of the particle emissions of a EURO 5 light-duty Diesel engine equipped with a wall flow Diesel Particulate Filter (DPF) showed that the DPF has a high removal efficiency for particles, especially in the range of 10-40 nm. Engine operating conditions do not have a significant impact on particle emissions, while particle emissions during the regeneration phase are strongly dependent on DPF temperature.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Chemistry, Physical
Santanu Saha, Yasuhisa Adachi
Summary: In this study, the effect of polymer coating on the electrokinetic shielding of colloidal particles was investigated by measuring the electrophoretic mobility of negatively charged polystyrene sulfate latex (PSL) particles adsorbed with electrostatically neutral polyethylene oxide (PEO) chains of various molecular weights under different ionic strengths. The results showed that the presence of substantial adsorbed neutral polymer on the particle surface reduced the absolute value of electrophoretic mobility. However, even with a sufficiently thick polymer layer compared to the electric double layer (EDL), the electrophoretic mobility never vanished, indicating the incomplete electrokinetic shielding by the adsorbed neutral polymer. A mathematical model was proposed to explain this phenomenon, and the experimentally obtained data were successfully justified using an analytical expression derived from the Ohshima-Kondo theory under the Debye-Huckel approximation.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Physical
N. F. Abu Bakar, B. Basaruddin, M. Nazli Naim, I. Wuled Lenggoro, M. Iijima, H. Kamiya
Summary: This study investigates the particle velocity and bubble growth rate in an aqueous system during continuous and pulsed direct current electrophoretic deposition (EPD) of polystyrene latex (PSL) particles. The results show that pulsed DC leads to a more uniform particle velocity and reduced bubble growth rate.
COLLOID AND POLYMER SCIENCE
(2023)
Article
Chemistry, Physical
Tomonori Fukasawa, Naoki Maruyama, Kosei Ono, Toru Ishigami, Kunihiro Fukui
Summary: The study found that with the increase of applied electric field, the accumulation of ions in the slipping layer decreased, and ions with higher hydrophilicity were less likely to accumulate. These results provide important information for evaluating the ion-accumulation state based on electrophoretic mobility measurements.
COLLOID AND INTERFACE SCIENCE COMMUNICATIONS
(2021)