Chung-Ang University

About: Chung-Ang University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Population & Thin film. The organization has 13381 authors who have published 26978 publications receiving 416735 citations. The organization is also known as: CAU & Chung.

Simple model for ion-assisted etching using Cl/sub 2/--Ar inductively coupled plasma: effect of gas mixing ratio

Abstract: In this paper, we investigated the relationships between Cl/sub 2/--Ar mixing ratio, plasma parameters, plasma chemistry and etching kinetics using a combination of experimental investigations and modeling. Modeling of plasma chemistry was represented by zero-dimensional quasi-stationary model assuming electron energy distribution to be close to Maxwellian. For the surface kinetics, we used the simplified model based on the theory of active surface sites. The model confirmed the possibility of nonmonotonic behavior of etch rate behavior in the system with monotonic changes of fluxes of active species.

The transgenerational impact of benzo(a)pyrene on murine male fertility

Abstract: background: Benzo(a)pyrene (BaP) is an endocrine toxicant that is widely distributed in the environment. The adverse effects of BaP on fertility are well documented, however its effects on fertility in the subsequent generations are not known. We aimed to investigate the transgenerational effects of BaP on male fertility in mice. methods: Six-week-old male mice (F0) were orally administered BaP (1 or 10 mg/kg body weight) or corn oil, daily for 6 weeks. The male mice were mated with untreated female mice to produce F1 offspring. The F2 and F3 progeny were produced in a similar manner. Testes and spermatozoa were collected from 14-week-old F0, F1, F2 and F3 males in order to assess male fertility parameters, namely testis histology, sperm count, sperm motility and sperm penetration (sperm penetration assay). results: Oral administration of a high dose of BaP induced testicular malformation and decreased numbers of seminiferous tubules with elongated spermatids for three generations studied (i.e. F0 to F2) with significant decreases in F0 and F2. It also significantly decreased sperm motility in F0. BaP significantly decreased sperm count in the group treated with a high dose of BaP in all generations except the F3 generation. The sperm fertility index (SFI) also decreased significantly for two generations. Of the fertility parameters measured, sperm count and SFI were the more sensitive parameters in our study. conclusions: Exposure to BaP decreases the fertilization potential of exposed males and has an adverse impact on sperm function and fertility in subsequent generations. The BaP effect on fertility can be described as a transgenerational effect for F2 generation.

One-pot synthesis of intermetallic electrocatalysts in ordered, large-pore mesoporous carbon/silica toward formic acid oxidation.

Abstract: This study describes the one-pot synthesis and single-cell characterization of ordered, large-pore (>30 nm) mesoporous carbon/silica (OMCS) composites with well-dispersed intermetallic PtPb nanoparticles on pore wall surfaces as anode catalysts for direct formic acid fuel cells (DFAFCs). Lab-synthesized amphiphilic diblock copolymers coassemble hydrophobic metal precursors as well as hydrophilic carbon and silica precursors. The final materials have a two-dimensional hexagonal-type structure. Uniform and large pores, in which intermetallic PtPb nanocrystals are significantly smaller than the pore size and highly dispersed, enable pore backfilling with ionomers and formation of the desired triple-phase boundary in single cells. The materials show more than 10 times higher mass activity and significantly lower onset potential for formic acid oxidation as compared with commercial Pt/C, as well as high stability due to better resistivity toward CO poisoning. In single cells, the maximum power density was high...