• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.263-266
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• 2004

A sensitive, selective and rapid method has been developed for the determination ${\mu}$g/L level of vanadium ion based on the rapid reaction of vanadium(V) with 2-(2-quinolylazo)-5-diethylaminophenol (QADEAP) and the solid phase extraction of the colored chelate with $C_{18}$ cartridge. The QADEAP reacts with V(V) in the presence of citric acid-sodium hydroxide buffer solution (pH = 3.5) and cetyl trimethylammonium bromide (CTMAB) medium to form a violet chelate of a molar ratio 1 : 2 (V(V) to QADEAP). This chelate was enriched by solid phase extraction with $C_{18}$cartridge and the enrichment factor of 50 was obtained by elution of the chelates from the cartridge with ethanol. The molar absorptivity of the chelate is $1.28 {\times}10^5L\;mol^{-1}cm^{-1}$ at 590 nm in the measured solution. Beer's law is obeyed in the range of 0.01-0.6 ${\mu}$g/mL. The detection limit is 0.04 ${\mu}$g/L in the original samples. This method was applied to the determination of vanadium(V) in water and biological samples with good results.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.143.3-144
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• 2003

A Korean isolate of Pepper mild mottle virus (PMMoV-Kr) was isolated from a diseased pepper crop in Chunchon, Korea. The isolate was biologically purified on Nicoticaa tabacum cv. Xanthi-nc by successive single local transfer steps, and propagated on N. tabacum cv. Samsun. PMMoV-Kr could systemically infect on N. glauca, N. benthmiana, N. occidentalis and Lycopersicon esculentum, which is typical of known isolates of PMMoV. PMMoV-Kr belongs to the pathotype P1,2 based on pepper-tobamoviral indicator experiments; Capsicn chinone harboring L3 gene revealed resistant (necrotic local lesion on inoculated leaf, HR) whereas L+, L1 and L2 pepper plants expressed susceptible reactions of mosaic systemic symptoms for the isolate. To confirm the pathology and delineate symptom determinant of the isolate, full-length cDNAs of PMMoV-Kr were amplified by RT-PCR with a primer set corresponding to the 5'- and 3'-ends of PMMoV. The RT-PCR molecules amplified from genome RNA of the isolate was cloned into the pUC18 vector. Full-length cDNA clones constructed under the control of the T7 RNA promoter could be successfully transcribed to produce in vitro transcript RNA. Infectivity of the capped transcripts and its progeny virus was verified by Western blot and RT-PCR analyses.

• Journal of Environmental Science International
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• v.19 no.7
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• pp.871-877
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• 2010

The objectives of this study were to compare growth of Pllioblastus pygmaed and soil characteristics as affected by difference of soil thickness and mixture ratio in shallow-extensive green roof module system, and to identify the level of soil thickness and mixture as suitable growing condition to achieve the desired plants in green roof. Different soil thickness levels were achieved under 15cm and 25cm of shallow-extensive green roof module system that was made by woody materials for $500{\times}500{\times}300mm$. Soil mixture ratio were three types for perlit: peatmoss: leafmold=6:2:2(v/v/v, $P_6P_2L_2$), perlit: peatmoss: leafmold=5:3:2(v/v/v, $P_5P_3L_2$) and perlit: peatmoss: leafmold=4:4:2(v/v/v, $P_4P_4L_2$). On June 2006, Pllioblastus pygmaed were planted directly in a green roof module system in rows. All treatment were arranged in a randomized complete block design with three replication. The results are summarized below. In term of soil characteristics, Soil acidity and electric conductivity was measured in pH 6.0~6.6 and 0.12dS/m~0.19dS/m, respectively. Organic matter and exchangeable cations desorption fell in the order: $P_4P_4L_2$ > $P_5P_3L_2$ > $P_6P_2L_2$. $P_6P_2L_2$ had higher levels of the total solid phase and liquid phase, and $P_4P_4L_2$ had gas phase for three phases of soil in the 15cm and 25cm soil thickness. Although Pllioblastus pygmaed was possibled soil thickness 15cm, there was a trend towards increased soil thickness with increased leaf length, number of leaves and chlorophyll contents in 25cm. The growth response of Pllioblastus pygmaed had fine and sustain condition in order to $P_6P_2L_2$ = $P_5P_3L_2$ > $P_4P_4L_2$. However, The results of this study suggested that plants grown under $P_4P_4L_2$ appear a higher density ground covering than plants grown under $P_6P_2L_2$. Collectively, our data emphasize that soil thickness for growth of Pllioblastus pygmaed were greater than soil mixture ratio in shallow-extensive green roof module system.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.498-502
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• 1998

In order to develop a natural food preservative, freeze dried plantain (Plantago asiatica L.) was extracted with several solvents, and the antimicrobial activity was investigated. The methanol extract exhibited antimicrobial activites against five strains of bacteria such as Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Vibrio parahaemolyticus. The methanol extract at the concentration of 1.0 mg/ml completely inhibited the growth of B. subtilis and V. parahaemolyticus. Antimicrobial activity of the ethylacetate fraction from the methanol extract was the strongest compared with those of other solvent fractions such as n-hexane, chloroform, n-butanol and water. The ethylacetate fraction showed the inhibitory effect at the concentration of 0.5 mg/disc on the growth of B. subtilis and V. parahaemolyticus.

• Journal of the Korean institute of surface engineering
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• v.39 no.2
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• pp.49-56
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• 2006

In this study, the movable flame hardening process of 12Cr steel for a uniform hardness and desirable residual stress have been investigated. For this, the temperature cycles have been controlled accurately as a function of the three processing variables, the flame intensity $I_f$, the scanning velocity $V_s$, and the initial flame holding time $t_h$, where the standard surface temperature $T_{s,\;max}$, was maintained at $960^{\circ}C$. The optimized conditions were $V_s=0.68mn/s\;and\;t_h=67sec$ for the $C_3H_8:O_2\;=\;5:20l/min,\;V_s=0.80mm/s$ and $t_h=56sec$ for the $C_3H_8:O_2=6:24l/min,\;V_s=1.01mm/s\;and\;t_h=48sec$ for the $C_3H_8:O_2=7:28l/min,\;and\;V_s=1.15mm/s$ and $t_h=39sec$ for the $C_3H_8:O_2$=8:32 l/min. The optimally flame-hardened surface exhibited uniform distributions of the hardness and residual compressive stress over the treated area with moderate levels of $470{\sim}490HV_{0.2}$in hardness and $-300{\sim}-450MPa$ in residual stress, which were acceptable on the basis of the acceptance criteria of Siemens AG-KWU and GE Power Generation Engineering.

• Food Science and Preservation
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• v.22 no.6
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• pp.886-892
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• 2015

The antimicrobial effects of ten isothiocyanates (ITCs) present in cruciferous vegetables and radish root hydrolysate were investigated against pathogenic bacteria from olive flounder. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured against two gram-positive bacterial strains (Streptococcus parauberis, S. iniae) and four gram-negative bacterial strains (Edwardsiella tarda, Vibrio ichthyoenteri, V. harveyi, Photobacterium damselae) by using a broth microdilution technique. The antibacterial activity of ITCs was in the order sulforaphane > sulforaphene > phenylethyl ITC > erucin > benzyl ITC > iberin > I3C > allyl ITC > phenyl ITC > hexyl ITC. The susceptibility of fish pathogens to ITCs was in the order of V. harveyi > E. tarda > P. damselae > S. parauberis > S. iniae > V. ichthyoenteri. Antimicrobial activity (MIC) of radish root hydrolysate was 0.250 mg/mL against S. iniae, 0.438 mg/mL against S. parauberis, and 0.500 mg/mL against both E. tarda and V. harveyi. The aliphatic ITCs were potent inhibitors of the growth of fish pathogens, followed by aromatic ITCs and indolyl ITC. The presence of a double bond in the chemical structure of ITCs decreased antibacterial activity, while ITCs with a thiol (-S-) group and a longer carbon chain increased antibacterial activity. These results suggest that ITCs have strong antibacterial activities and may be useful in the prevention of fish pathogens.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.373-378
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• 2007

A micro organism Agrobacterium tumifacient as an immobilized cell on a solid support was presented as a new biosorbent in a simple and sensitive spectrophotometry determination of Ni(II) in various samples using 4-hydroxy benzaldehyde-4-bromophenyl hydrazone as a color developing agent (λmax 497 nm) at pH 4.0 ± 0.2. Beer's law was obeyed over the range of 0.01-0.1 μg L-1. The molar absorptivity and Sandell's sensitivity were 1.285 × 105 L mol-1cm-1 and 0.007245 μg cm-2 respectively. Under these conditions, the preconcentration factor obtained was 82, and the detection limit achieved was 0.05 μg L-1. The detailed study of various interfering ions made the method more sensitive and selective. The recovery of Ni(II) from various samples range from 97.75 to 99.35%. The present method was successfully applied for the determination of Ni(II) in spiked, natural water and alloy samples. The proposed method was compared with reported methods in terms of Student's ‘t'-test and Variance ratio ‘f'-test which indicates that there is no significant difference between proposed and literature method at 95% confidence level.

• Tuberculosis and Respiratory Diseases
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• v.42 no.6
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• pp.900-912
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• 1995

Background: Although graded exercise stress tests are widely used for the evaluation of cardiorespiratory performance, normal standards on respiratory gas exchange and ventilatory functions at maximal exercise in Koreans have not been well established. The purpose of this study is to provide reference values on these by sex and age, along with derivation of some of their prediction equations. Method: Symptom-limited maximal exercise test was carried out by Bruce protocol in 1,000 healthy adults consisting of 603 males and 397 females, aged 20~66 years. Among them VC, $FEV_1$ and MVV were also determined in 885 cases. All the subjects were members of a health center, excluding athletes. During the exercise, subjects were allowed to hold on to front hand rail of the treadmill for safety purpose. Results: The $VO_2\;max/m^2$, $VCO_2\;max/m^2$ and $V_E\;max/m^2$ were greater in males than in females and decreased with age. The RR max in men and women was similar but decreased slightly with age. The $V_T$ max was markedly greater in men but showed no significant changes with age in either gender. The mean of $V_T$ max/VC, $V_E$ max/MVV and BR revealed that there were considerable ventilatory reserves at maximal exercise even in older females. The regression equations of the cardinal parameters obtained using exercise time(ET, min), age(A, yr), height(Ht, cm), weight(W, kg), sex(S, 0=male; 1=female), VC(L), $FEV_1$(L) and $V_E$ max(L) as variables are as follows: $VO_2\;max/m^2$(L/min)=1.449+0.073 ET-0.007A+0.010W-0.006Ht-0.209S, $VCO_2\;max/m^2$(L/min)=1.672+0.063ET-0.008A+0.010W-0.005Ht-0.319S, VE max/$m^2$(L/min)=58.161+1.503ET-0.315A-9.871S or VE max/$m^2$(L/min)=47.873+6.548 $FEV_1$-5.715 S, and VT max(L)=1.497+0.223VC-0.493S. Conclusion: Respiratory gas exchange and ventilatory variables at maximal exercise were studied in 1,000 non-athletes by Bruce protocol. During exercise, the subjects were allowed to hold on to hand rail of the treadmill for safety purpose. We feel that our results would provide ideal target values for patients and healthy individuals to be achieved, since our study subjects were members of a health center whose physical fitness levels were presumably higher than ordinary population.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.766-771
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• 1994

A number of molybdenum(VI), -(V), and -(IV) oxo complexes with S-methyl 3-(2-hydroxyphenyl)methylenedithiocarbazate and its derivatives as the ONS-donor metal-binding substrate are synthesized. The Mo(VI)-dioxo complexes are cis-dioxo Mo$O_2$L(D), where D is solvent molecules such as MeOH, DMF, Py(pyridine), DMSO, and ${\gamma}$-Pic(${\gamma}$-picoline). The Mo(V)-oxo complexes are of the type (PyH)[MoO(NCS$)_2$L] with an octahedral geometry. The Mo(IV)-oxo complexes, MoOL are derived from corresponding Mo(VI)-dioxo complexes by oxo abstraction with PP$h_3$. The complexes are characterized by IR, $^1$H-NMR, UV-Vis spectroscopy and cyclic voltammetry. On the basis of ligand displacement reaction, the qualitative order of D binding for Mo$O_2$L(D) complexes is also discussed.

• Journal of the Korean Society of Combustion
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• v.22 no.3
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• pp.17-22
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• 2017

An experimental study has been conducted to elucidate the effect of AC electric field on behaviors of laminar lifted flame in nitrogen-diluted methane coflow-jets. Our concerns are focued on the regime to show a decrease in liftoff height, $H_L$ with increasing nozzle exit velocity, $U_O$ (hereafter, $decreasing-H_L$). The $H_L$ with $U_O$ near flame extinction were measured by varying the applied AC voltage, $V_{AC}$ and frequency, $f_{AC}$ in a single electrode configuration. The behavior of $H_L$ with a functional dependency of $V_{AC}$ and $f_{AC}$ was categorized into two regime : (I) $H_L$ decreased for nozzle diameter, D = 1.0 mm, and (II) $H_L$ increased in the increase of $f_{AC}$ for a fixed $V_{AC}$ in a D = 4.0, 8.4 mm. The lifted flames in $decreasing-H_L$ region was unstable in high voltage regimes while the $H_L$ showed a decreasing tendency with $U_O$ except them. Such behaviors in $H_L$ were also characterized by functional dependencies of related physical parameters such as $V_{AC}$, $f_{AC}$, $U_O$, fuel mole fraction ($X_{F.O}$) and D.