• Journal of computational fluids engineering
• /
• v.14 no.4
• /
• pp.62-66
• /
• 2009

The control of particle concentration distribution in a pipe with an orifice and a sheath air is numerically investigated. When using Eulerian approach, there is no great change in the concentration distribution by the shape of orifice and molecular diffusivity. As the Reynolds number becomes small, the effect of orifice on the concentration distribution is decreased. For small Reynolds number, the concentration distribution can be effectively controlled by using a sheath air. The effect of the sheath air on the concentration distribution is increased, as the Reynolds number becomes small.

• Journal of the Korean Chemical Society
• /
• v.17 no.4
• /
• pp.240-246
• /
• 1973

An analytic expression for the intensity of collision-induced light scattering obstained by introducing both short-range and long-range effects on the induced anisotropy. By taking argon as a specific example, it is shown that a narrow band at small frequency shifts is caused by long-range effects, while a broad band in the far wing of the spectrum is due to short-range effects. The overall intensity is a synthesis of these two bands and does not follow a simple exponential form. As temperature increases, the intensity at large frequency shifts increases makedly, while at small frequency shifts it changes little.

• The Korean Journal of Mycology
• /
• v.44 no.3
• /
• pp.145-149
• /
• 2016

Pseudeurotium bakeri KNU14-21 isolated from crop field soil is a previously unreported fungal species in Korea. This fungal species was identified through morphological and molecular characteristics. Based on the shape and size of conidia and conidiophores as well as the internal transcribed spacer region of rDNA, the isolate was confirmed to be Pseudeurotium bakeri. This species has not been previously reported from Korea, and this is the first report of its incidence in Korea.

• KSBB Journal
• /
• v.16 no.2
• /
• pp.115-122
• /
• 2001

Molecular imprinting has now been established as a technique which allows the creation of tailor-made binding sites for many classes of compounds. MIPs were prepared by covalent and non-covalent chemical bonding systems, by interactions between functional monomer and template. The shape of MIP is divided to particle and membrane. MIP membranes can be prepared by surface imprinting, in-situ polymerization, wet phase inversion and the dry phase inversion method. MIPs have been mainly used for analytical separation and biosensor systems to separate and detect chiral compounds and materials with similar structures. However the application of MIP by the chemical industries is still in its infancy stages. This review summarizes the preparative characteristics and applications of MIP with respect to chiral separations and biosensors.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1996.10a
• /
• pp.28-29
• /
• 1996

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.12 no.1
• /
• pp.11-17
• /
• 1999

Aging characteristics of the crosslinked polyethylene have been measured after applying electrical, thermal and combined stresses. ICP and FT-IR measurements confirmed diffusion of low molecular weight components such as antioxidant and presence of carbonyl group. Carbonyl group of aged crosslinked polyethylene under combined stress was detected by FT-IR. As deterioration of the crosslinked polyethylene progresses, crystallinity degree and density decrease. Also, dielectric properties have been measured by tan $\delta$ and $\varepsilon$$_{r}$ measurements. The three-parameter Weibull distribution was found to be the best suited among other probabilistic distribution representing the dielectric breakdown strength of aged crosslinked polyethylene. The scale parameter and location parameter decreases as the applied stress increases. The shape parameter increases as the stress increases.s.

• Bulletin of the Korean Chemical Society
• /
• v.2 no.4
• /
• pp.132-138
• /
• 1981

Ab initio molecular orbital calculations have been performed in an effort to determine which types of chemical interactions play essential roles for the system, , $H_2O+CH_2SH^+$, and $H_2O+ CH_2S$. The most important contribution to the interaction energy in controlling reaction path is the exchange repulsion energy, EX, which is largely responsible for the shape of the total interaction energy curve. In the ion-molecule reaction, prior protonation of thioformaldehyde or prior deprotonation of water leads to formation of the corresponding ionic adducts ($H_2O+CH_2SH$ and $HOCH_2S^-$), with no barrier to reaction, simulating specific acid and base catalysis, respectively, as in the case of formaldehyde. Otherwise, approach of water to thioformaldehyde gives rise to a completely repulsive interaction.

• BMB Reports
• /
• v.54 no.7
• /
• pp.356-367
• /
• 2021

Cell-based therapy is a promising approach in the field of regenerative medicine. As cells are formed into spheroids, their survival, functions, and engraftment in the transplanted site are significantly improved compared to single cell transplantation. To improve the therapeutic effect of cell spheroids even further, various biomaterials (e.g., nano- or microparticles, fibers, and hydrogels) have been developed for spheroid engineering. These biomaterials not only can control the overall spheroid formation (e.g., size, shape, aggregation speed, and degree of compaction), but also can regulate cell-to-cell and cell-to-matrix interactions in spheroids. Therefore, cell spheroids in synergy with biomaterials have recently emerged for cell-based regenerative therapy. Biomaterials-assisted spheroid engineering has been extensively studied for regeneration of bone or/and cartilage defects, critical limb ischemia, and myocardial infarction. Furthermore, it has been expanded to pancreas islets and hair follicle transplantation. This paper comprehensively reviews biomaterials-assisted spheroid engineering for regenerative therapy.

• Research in Plant Disease
• /
• v.27 no.3
• /
• pp.107-114
• /
• 2021

During a disease survey on weeds and minor cultivated crops in Korea, a brown leaf spot disease was observed on Sonchus asper. Leaf lesions were round or irregular in shape, and grayish brown to brown with a purple margin. In severe infection, lesions enlarged and coalesced, resulting in blighting of the leaves. The isolates from these leaf lesions were identified as Alternaira sonchi based on morphological characteristics and phylogenetic analyses of Internal transcribed spacer region, Alternaria allergen a1, glyceraldehyde 3-phosphate dehydrogenase, RNA polymerase II, and translation elongation factor genes. This study provides a comprehensive description of the morphological characteristics and phylogenetical traits of A. sonchi causing brown leaf spot on S. asper in Korea.

• Bulletin of the Korean Chemical Society
• /
• v.9 no.5
• /
• pp.275-280
• /
• 1988

The high resolution IR spectra of freon-12($CF_2Cl_2$) for the bands of 671cm$^{-1},\;922cm^{-1},\;1102cm^{-1},\;and\;1160cm^{-1}$ were taken and the rotational vibrational analysis has been carried out. The band types of $671cm^{-1}\;and\;1102cm^{-1}$ were confirmed to be A and those of $922cm^{-1}\;and\;1160cm^{-1}$ were confirmed to be B. The theoretically synthesized spectra were matched with the experimentally obtained spectra to get some informations of the molecular rotational behavior as well as the overall band shape of the spectra.