• Journal of the Korean Chemical Society
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• v.33 no.2
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• pp.168-176
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• 1989

Theoretical analysis of HF chemical laser models are performed through chemical reaction kinetics, gain process and stimulated emission process. A chemical laser of F+$H_2$ nonchain reaction is investigated through V-R transitions of excited HF for vibrational levels up to v = 3 and rate equations including nonchain pumping and deactivation. On this analysis, harmonic and anharmonic vibrational levels are considered separately and the results of the corresponding power calculations are showed very small difference between the two. Output powers are calculated with variation of temperature and initial concentrations of $H_2$. A HF chemical laser of $H_2$+$F_2$ chain reaction is also simulated with a premixed initial condition. Results of present model calculations are satisfactory through comparison with detailed calculations reported by others.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.414-419
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• 2006

Effects of water vapor, hydrocarbons, and CO, which are inevitably included in exhaust gases of combustion, on a combined $De-NO_{x}$ process of non-thermal plasma and $NH_{3}$ SCR (Selective Catalytic Reduction) have been investigated. Test results showed that fast SCR reaction enhanced $De-NO_{x}$ rate under the low temperature conditions, $150{\sim}200^{\circ}C$ The present test, however, showed that the role of the fast SCR reaction can be significantly suppressed by addition of hydrocarbons in a non-thermal plasma reactor. Detailed investigation verified that such suppressed role of the fast SCR reaction could be caused by the $NO_{2}/NO_{x}$ ratio modified by aldehydes produced from hydrocarbons in a non-thermal plasma reactor. In addition, the present study was confirmed that the effects of water vapor and CO were not noticeable compared with the hydrocarbon effects.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1286-1286
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• 2001

Despite extensive theoretical and experimental studies the structure of the protein-solvent interface is subject of many controversy. Understanding the processes that occur in aqueous solution requires understanding of the solvent influence on the structure of protein. The aim of this study is to investigate the applicability of NIR methods in the study of hydration phenomena in protein solutions. Temperature-induced changes in NIR spectra of -lactoglobulin (BLG) in aqueous solutions have been investigated by means of two-dimensional correlation spectroscopy (2DCOS) and principal component analysis (PCA). With the temperature increase the balance of forces between the BLG's interaction with itself and the BLGs interaction with its environment is disrupted leading to BLG unfolding. Significant differences of 2D signals and distinct discrepancies of loading on PC1 and PC2 were observed as a result of temperature increase. In the native folded conformation of BLC, most of the nonpolar amino acids are hidden in the centre of the structure, out of contact with water molecules, while charged groups are outside, in the contact with water. The polar groups promote low density Ih-type structure in the water outside this first hydration shell. When BLG unfolds it assumes a more extended configuration on which the previously buried nonpolar groups are exposed to water and promote the higher density II-type structure outside its first shell. Detailed assignments of bands attributed to the bulk water, different states of the hydrated water and the changed conformation of BLG are proposed.

• Korean Journal of Plant Taxonomy
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• v.42 no.4
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• pp.330-334
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• 2012

Distribution of Juncus fauriei L$\acute{e}$v. & Vaniot were restricted in Japan and Russia in previous literatures. We found its new distribution in the Korean peninsula: wet meadows of sandy seashore in Ha-Jo-Dae, Kangwon province. The plants have flattened stems (usually coiled) and black-colored margin in tepals. These are key characters to distinguish J. fauriei from J. decipiens, J. setchuensis, J. haenkei, and J. brachyspathus, which are closely related Korean taxa in the section Juncotypus. We provide description, distribution, and detailed photos of J. fauriei, and key for Korean taxa of sect. Juncotypus. The plant is named as "Geom-Jeong-Nap-Jak-Gol-Pul" in Korean.

• Journal of Environmental Science International
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• v.14 no.5
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• pp.499-511
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• 2005

This study was performed to determine the effects of genetic polymorphisms, such as glutathione S-transferase ${\mu}1(GSTM1)$, glutathione S-transferase ${\Theta}1\;(GSTM1)$, glutathione S-transferase ${\pi}l (GSTP1)$, aryl hydrocarbon N-acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), cytochrome P450 1A1 (CYP1A1) on the concentrations of urinary 1-hydroxypyrene (1-OHP) and 2-naphthol in general population with no occupational exposure to polycyclic aromatic hydrocarbons (PAHs). Study subjects were 257 men who visited a health promotion center in Susan. A questionnaire was used to obtain detailed data about age, smoking, drinking, body fat mass, intake of fat etc. Urinary l-OHP and 2-naphthol concentration were analyzed by HPLC system with a fluorescence detector. A multiplex PCR method was used to identify the genotypes for GSTM1 and GSTT1. The polymorphisms of GSTP1, NAT2, CYP1A1 and CYP2E1 were determined by the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Urinary 1-OHP concentration was higher in deleted genotype of GSTM1, increased as smoking and alcohol drinking increased. Urinary 2-naphthol concentration was also rely on the age and smoking. Neither genetic polymorphism nor drinking-related factors were significantly related to urinary 2-naphthol concentration. No significant relation was found between physical characteristics and concentrations of urinary PAHs metabolites in the subjects, but the geometric mean of urinary 1-OHP and 2-naphthol was higher in the group with higher value compared to median value. These data suggest that in general population occupationally not exposed to PAHs, urinary concentration of PAHs metabolites is influenced by smoking, alcohol drinking and deleted genotype of GSTM1 in 1-OHP and smoking in 2-naphthol.

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.177-185
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• 2009

The failure analysis of scales deposited on automotive thermostat housing has been carried out. Observations using energy dispersive spectroscopy and electron probe micro analyzer indicate that the main components of scales are some of additives of coolant used. For a detailed investigation of organic matters pyrolysis-GC/MS is employed. The result shows that the main organic component is benzoic acid and furthermore, a small amount of acetophenone, benzene and phenyl group is detected. Based on the results of failure analysis performed, the scales on automotive thermostat housing appear due to the deposition of coolant components, followed by crevice corrosion, into gap between housing and rubber horse. New accelerated test methodology, which could mimic the scale formation and the crevice corrosion on thermostat housing, is developed considering the above results. In order to reproduce the real operating conditions, the accelerating factors, i.e. temperature and humidity, are changed and programmed. The reproducibility of the accelerated test proposed is confirmed after analyzing the scales obtained from the accelerated test.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.333-333
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• 2011

We studied the H/D exchange kinetics of pure and acid dopped water-ice film by using the techniques of reactive ions scattering (RIS) and low energy sputtering (LES) with low kinetic energy cesium ion beam (<35 eV). From RIS, neutral water isotopomers were detected in the form of cesium-molecule ion clusters, $CsX^+$ (X= $H_2O$, HDO, $D_2O$). Ionic species, like $H_3O^+$, $DH_2O^+$, $D_2HO^+$, $D_3O^+$, adsorbed on the surface were ejected via LES process. Those techniques allowed us to trace the isotopomeric populations of water-ice film. To show the catalytic effect of excess proton in the H/D exchange reaction, our study was conducted with two types of water-ice films. In film 1, about 0.5 BL of $H_2O$ was adsorbed on HCl (0.1 ML) dopped $D_2O$ (8 BL) film. In film 2, similar amount of $H_2O$ used in film 1 was adsorbed on pure $D_2O$ film. Kinetic data were obtained from each film type for 90-110 K (film 1) and 110-130 K (film 2) and fitted with numerically integrated lines. Through the Arrhenius plot of kinetic coefficient deduced from fitting of the H/D exchange reaction, the activation energy of film 1 and 2 were estimated to be $10{\pm}3kJmol^{-1}$ and $17{\pm}4kJmol^{-1}$. This activation barrier difference could be understood from detailed pictures of H/D exchange. In film 2, both the formation of ion pair, $H_3O^+$ and OH. and proton transfer were needed for the H/D exchange. However, in film 1, only proton transfer was necessary but ion pair formation was not, so this might reduce the activation energy.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.201-208
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• 2015

The role of RNA-binding proteins (RBPs) to regulate expression of genes seems to be very important. RBPs play important roles in RNA related bioprocess such as transcription, pre-mRNA splicing, polyadenylation, transport, localization, translation, turn over and maintenance of structure. Despite of many researches on RNA binding proteins, detailed mechanisms of these proteins have not been fully understood. It seems that many parts of RBPs remains unknown and should be characterized for the better understanding of gene expression. Recently, genetic, biochemical, and bioinformatic analysis of genomes revealed a vast array of RBPs and many parts are interesting to understand bioprocessing including gene expression.

• Applied Chemistry for Engineering
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• v.18 no.1
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• pp.71-76
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• 2007

We have demonstrated the resonant resistance pattern changes of the polymer film in the quartz crystal analysis by the function of the molecular polarity phase transition phenomena. PVA and PMMA/PVAc blend films were used as hydrophilic and/or hydrophbic film, respectively. In the comparison between the hydrophilic shows the pattern changes near by the phase transition temperature. For more detailed explanation, the static capacity in the oscillation parameter was measured and the morphology of Au quartz crystal electrode was studied by AFM. It is suggested that the different resonant resistance pattern change is reliable in the condition of different polarity, and the conclusion is important to analysis of the real mechanism a normal quartz crystal experiments.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.246-249
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• 2011

SolarPACES is an international cooperative network bringing together teams of national exports from around the world to focus on the development and marketing of concentrating solar power systems (also known as solar thermal power systems). It is one of a number of collaborative programs, called Implementing Agreements, managed under the umbrella of the International Energy Agency to help find solutions to worldwide energy problems. Technology development is at the core of the work of SolarPACES. Member countries work together on activities aimed at solving the wide range of technical problems associated with commercialization of concentrating solar technology, including large-scale system tests and the development of advanced technologies, components, instrumentation, and systems analysis techniques. In addition to technology development, market development and building of awareness of the potential of concentrating solar technologies are key elements of the SolarPACES program The Implementing Agreement specifies broad "Tasks," or thematic areas of work SolarPACES currently has three ongoing tasks, focusing on concentrating solar electric power systems (Task I), solar chemistry research (Task II), and solar technology and applications (Task III). An Operating Agent, nominated by the ExCo, is responsible for overseeing the work of each task Each task maintains a detailed program of work that defines all task activities, including their objectives, participants, plans, and budgets. In addition to technical reports of the activities and their participants, accomplishments and progress are summarized in the SolarPACES annual report. Many SolarPACES activities involve close cooperation among member countries (either through sharing of task activities or, occasionally, cost-sharing), although some cooperation is limited to sharing of information and results with other participants. In this paper, structure, works, and members of SolarPACES and Korean activies in the SolarPACES are introduced.