• Applied Biological Chemistry
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• v.35 no.6
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• pp.495-500
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• 1992

For the production of 6-hydroxynicotinic acid from nicotinic acid, bacteria capable of assimilating nicotinic acid as a sole carbon, nitrogen and energy source were isolated from soils. Among them, SH-007, newly isolated strain having the best acitivity of nicotinic acid hydroxylase was selected and identified as Pseudomonas sp. The specific acitivity of nicotinic acid hydroxylase of Pseudomonas sp. was highest when the strain was cultured at $30^{\circ}C$ for 24 hrs in the medium (pH 7.5) containing 2 g nicotinic acid, 1 g $(NH_4)_2SO_4$, and 0.5 g peptone per liter. The addition of 1.5 g/l of nicotinic acid into the 24 hrs incubated culture medium resulted in the 12% higher specific acitivity of nicotinic acid hydroxylase than that of the non-added control after further 18 hrs incubation. In the 6-hydroxynicotinic acid production through the reaction with resting cells, 2.22 g/l of 6-hydroxynicotinic acid was produced from 2 g/l of nicotinic acid after incubation of 3 hrs under optimum conditions, which correpsonds to 98.2% of theoretical 6-hydroxynicotinic acid yield.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.42-49
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• 2017

The application of electro-coagulation has been attempted to control the membrane fouling problem in a MBR (Membrane Bio-Reactor). This study examined the effects of the operating parameters (current density and contact time) of the electro-coagulation process on the change in the characteristics of activated sludge. The current density changed from 2.5 to 12, $24A/m^2$, and the contact time was varied from 0 to 2 and 6 hr, respectively. At a current density of $24A/m^2$ and 6 hr of operation, the MLSS changed from 6,800 to 7,000 mg/L (3% increase), but the MLVSS did not increase significantly. After 6 hr of operation, the soluble COD decreased from 71 to 37 mg/L under the $24A/m^2$ condition, from 113 to 67 mg/L under the $12A/m^2$ condition, and from 84 to 80 mg/L under the $2.5A/m^2$ condition. On the other hand, soluble-TN and -TP concentration showed slight changes. The soluble-EPS and Bound-EPS concentration decreased slightly with increasing current density. The membrane filtration performance of activated sludge before and after electro-coagulation was compared. The filtration resistances after electro-coagulation decreased from 6 to 61 %, particularly as the current density and contact time were increased. This indicates that electro-coagulation can be used to control membrane fouling in the MBR process.

• The Korean Journal of Zoology
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• v.33 no.3
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• pp.337-345
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• 1990

The properties of three esterases (E2, E6 and E11) which were previously purified from Pieris rapae L. were determined and physiological role of E6 was inferred using immunological methods. Based on inhibitor study, all of the purified esterases were found to be carboxylesterases (EC 3.1.1.1). The Km values for E2, E6 and E11 were determined to be 6.89 X 10-$^4$M. 3.19 $\times$ l0-$^4$M and 3.69 X 10-$^4$M, respectively. The molecular weights of E2, E6 and E11 were estimated to be 42 KD, 81 KD and 174 KD, respectively. The isoelectric points of E2, E6 and E11 were estimated to be pH 5.54, pH 5.89 and pH 6.50, respectively. The concentration of E6 during development was highest at the late 5th instar larval stage and that according to organs at the same stage was highest in midgut. These results suggest that E6 might be a hydrolase involved in the digestion of dietary lipids.

• ALGAE
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• v.19 no.3
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• pp.217-226
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• 2004

The present study is to examine the water quality and to analyze the plank tonic and benthic phytoplankton communities at 6 stations in the Dong River and its tributary streams of Kangwon Province from November, 2001 to March, 2002. During the studies, water temperature ranged from 3.5 to 12.8℃; pH, 6.5-7.9; DO, 9.29-11.36 mg·l^(-1); BOD_5, 0.20-2.38 mg·l^(-1); TN, 1.2842-3.1871 mg·l^(-1); TP, 0.0052-0.0576 mg·l^(-1); and SS, 0.85-9.62 mg·l^(-1). The standard of water quality according to the Korean Environmental Preservation Law showed the first class except St. 6 through the survey. Six taxa of plank tonic phytoplankton identified were poor flora in November, 2001. The representative species frequently observed were the diatoms Achnanthes lanceolata, Achnanthes minutissima, Cymbella minuta, Cymbella parva, Diatoma vulgare, Fragilaria construens, Gomphonema pervulum, Navicula cryptocephala, Nitzschia palea., Scenedesmus sp. of green algae and Stephanodiscus hantzschii. Monthly dominant species of phytoplankton were Achnanthes lanceolata and A. minutissima in both February and March, 2002, but the blue-green algae, Oscillatoria sp. and the diatom, Stephan discus hantzschii were predominant at some stations in March. Phytoplankton standing crops ranged from 9.84 ${\times}$ 10$^3$ to 3.56 ${\times}$ 10$^4$ cell·l$^{-1}$ in November and 1.68-2.99 ${\times}$ 10$^5$ cell·l$^{-1}$ in February, while it changed 4.52-8.01 ${\times}$ 10$^5$ cell·l$^{-1}$ at St. 1, 2, 3 and 1.03-1.71 ${\times}$ 10$^6$ cell·l$^{-1}$ at St. 4, 5, 6 in March. Benthic phytoplankton communities was composed of 38 taxa in November, 31 taxa in February and 23 taxa in March. It showed a contrary tendency to planktonic phytoplankton diversity. Benthic diatoms which were more than 25% of the total populations were Cymbella turgida, Diatoma vulgare, Cocconeis placentula, Navicula cryptocephala var. intermedia in November; Achnanthe lanceolata, Cocconeis placentula, Achnanthes minutissima in February; and Achnanthes lanceolata and Cyclotella meneghiniana in March.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.516-521
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• 1994

New seventeen imazapyr derivatives, 2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)-3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl)pyridine, 6 were synthesized and their pre-emergence herbicidal activity$(pI_{50})$ in vivo against Corn (Zea mays L.) and Pigweed (Amaranthus viridis L.) were studied by the pot test under paddly conditions. Quantitative structure activity relationships (QSARs) were analyzed using the physicochemical parameters of substituent(X) on the phenyl ring of 3-(N-methyl-N-X(sub.)-phenylaminooxoacetyl) group and regression analysis. The herbicidal activities were related to the steric effect of X-substituent. The effect was rationalized by paraholic function of MR and $L_1$, where the optimal values were MR=5.56 (Zea mays L.) and $L_1=3.34\;{{\AA}}$ (Amaranthus viridis L.). Among them, 2,5-difluoro substituted compound, 6i showed good herbicidal activity against Pigweed with excellent tolerance to Corn.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2565-2570
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• 2011

The reaction of bromoacetonitrile with 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[$16.4.1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^{10}$) containing a N-$CH_2$-N linkage produces 17-cyanomethyl-3,14-dimethyl-2,6,13,17-tetraazatetracyclo-[$16.4.1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^{11}$). The mono-N-functionalized macrocyclic complexes $[ML^2]^{2+}$ (M = Ni(II) or Cu(II); $L^2$ = 2-cyanomethyl-5,16-dimethyl-2,6,13,17-tetraazatricyclo[$16.4.0.0^{7.12}$]docosane) can be prepared by the reaction of $L^{11}$ with nickel(II) or copper(II) ion in acetonitrile. The N-$CH_2CN$ group attached to $[ML^2]^{2+}$ readily reacts with water or methanol to yield the corresponding complexes of $HL^3$ bearing one N-$CH_2CONH_2$ pendant arm or $L^4$ bearing one $N-CH_2C(=NH)OCH_3$ group. The $N-CH_2CONH_2$ or $N-CH_2C(=NH)OCH_3$ group of each complex is coordinated to the central metal ion. Both $[NiL^4(H_2O)]^{2+}$ and $[CuL^4]^{2+}$ are quite stable in acidic aqueous solutions, but undergo hydrolysis to yield $[Ni(HL^3)(H_2O)]^{2+}$ or $[Cu(HL^3)]^{2+}$ in basic aqueous solutions. In contrast to $[Cu(HL^3)]^{2+}$, $[Ni(HL^3) (H_2O)]^{2+}$ is readily deprotonated to form $[NiL^3 (H_2O)]^+$ ($L^3$ = a deprotonated form of $HL^3$) in basic aqueous solutions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.3
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• pp.274-282
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• 1998

This study deals with sinking resistance for purse seine, in the case of different d/l, ratio of twine diameter and leg length. Experiments carried out on the six types simplified reduced model seines which were made of knotless netting. The nettings were woven in different leg length 4.3, 5.0, 5.5, 6.0, 6.6 and 7.7mm of polyester 28 tex two threads two -ply twine, and each of the seines were named I, II, III, IV, V and Ⅵ seine. Dimension of seine models were 450cm for corkline and 85cm for seine depth, each seines rigged up 160g of float for a floatline and 50g (underwater weight) of lead for a leadline. Experiments were measured in the observation channel of a flume tank at the static conditions Sinking motion was recorded by the two sets TV-camera for VTR which were placed in top and side of the model seine, and reading coordinate carried out by the video digitization system. An analysis were calculated out by simultaneous differential equations for numerical method by Runge - Kutta - Gill sub - routine. The results obtained were as follows: 1. Average sinking speed of seine of seine margin was fastest for Ⅵ seine followed by V, IV, III, II and I seines. 2. The coefficient of resistance for a seine wall was depended upon the ratio of d/l : KD =0.081 (d/l )-0.5 3. The coefficient of resistance for netting bundle was not depended upon the ratio of d/l :CR = 0.91 (), d : Twine diameter, l : Leg length, : Density of netting materals, $\omega$ : Density of water

• Journal of Korean Society of Environmental Engineers
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• v.27 no.7
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• pp.777-784
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• 2005

The first flush phenomenon is defined as the initial period of road runoff during which the concentration of pollutants was significantly high. Road runoff contains significant loads of micro-particles, heavy metals and organic constituents. There were two major objectives of this study. The first objective was to characterize the road runoff. The second objective was to measure and evaluate particle sire distribution of the road runoff, Stormwater runoff was monitored on two sites of four lane road areas along with traffic volume. A total six storm events were monitored to characterize the road runoff. The quantity of road runoff and quality constituents, including chemical oxygen demand ($COD_{Cr}$), suspended solids(SS), total Kjeldahl nitrogen (TKN), ortho-phosphorus ($PO_4-P$), total phosphorus(TP), heavy metals and particle size distribution were analyzed. The results indicate that the concentration of SS, $COD_{Cr}$, TKN and TP ranges were $45{\sim}2,396\;mg/L$, $40{\sim}931\;mg/L$, $0.1{\sim}19.6\;mg/L$, and $0.2{\sim}25.1\;mg/L$, respectively. The results of the regression analysis between SS and the others constituents shows that $COD_{Cr}$, TP, Cu, Pb were highly correlated. And the results showed that the mean range of particle size and uniformity coefficient for road runoff were $6.7{\sim}23.4{\mu}$ and $6.4{\sim}10.2$, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.133-143
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• 2002

The textile industry is petting increased effort to manufacture the value-added products that gives the differentiated characters at every level of fiber and fabric production. The color is an important element to be used strategically in order to push up the value-added design. The colors of apparel products have a close relationship with the skin colors of consumers and their preference colors. This study was carried out to cluster the skin colors of the Korean women into several similar skin colors and to analyze their preference colors by the classified groups. We measured the skin colors of 354 Korean women. With color spectrometer, JX-777, we measured 4 points of the body; cheek with removing cosmetics off, forehead, rear neck and arm on the interior part near elbow. All subjects had been shown with 40 color chips and answered the preference colors and preference colors of apparel. Data were analysed to classify skin colors using K-means Cluster Analysis and Duncan test, Frequency and Chi square test on the preference colors about the clustered 3 groups. In doing so, we used in SPSS Win 10 statistical package. Findings were as fellows: 1) The skin colors of the Korean women were clustered into YR, R, and Y skin colors. The majority of the subjects, 324 observations had YR skin colors and the subjects were classified into 3 kinds of skin color groups who had YR skin colors. 2) The average skin colors of total 324 subjects was 5.23YR 6.49/4.09 in Munsell Color System(MCS), 66.56 in L value, 10.53 in a value, and 20.67 in b value. 3) The average skin color of Type 1 was 7.98YR 6.24/4.14 in MCS, 64.10 in L value, 15.05 in a value, and 24.0 in b value. For Type 2 was 7.30 YR 6.56/3.28 in MCS, 67.24 in L value, 6.89 in a value, and 18.4 in b value, and Type 3 was 7.01 YR 7.20/4.38 in MCS, 73.53 in L value, L 16.04 in a value, and 24.87 in b value. 4) The average face color of total 324 subjects was 7.31YR 6.65/3.56 in MCS, 68.13 in L value, 9.53 in a value, and 20.18 in b value. 5) The average face color of Type 1 was 4.19 YR 6.92/5.05 in MCS, 70.78 in L value, 13.2 in a value, and 25.32 in b value. For Type 2 was 5.24YR 6.33/3.79 in MCS, 64.94 in L value, 9.84 in a value, and 19.08 in b value. Type 3 was 5.4YR 6.85/4.68 in MCS, 70.1 in L value, 11.73 in a value, and 23.92 in b value. 6) The difference of mean values between the clustered 3 skin color groups showed significantly different except the a value of neck and H value of cheeks and H value of foreheads. 7) All 3 groups showed that the most preference colors and the most preference colors of apparel was 5R 4/14. and their preference colors were much more than the preference colors of apparel.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.67-73
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• 2009

This study was conducted to gather the basic data on making good use of a kind of groundsel (Ligularia fischeri). We have made methanol extracts from Ligularia fischeri and have also determined the effects of extracting temperature and time on the physiological activities of methanol extracts from Ligularia fischeri. Total phenolic compound and flavonoid contents in the methanol extracts from Ligularia fischeri at the extracting concentration of $1,000mg{\cdot}L^{-1}$ were $75.8-297.7mg{\cdot}L^{-1}$ and $45.6-173.6mg{\cdot}L^{-1}$. Total phenolic compound and flavonoid contents, and DPPH radical scavenging activities were most increased when Ligularia fischeri was extracted with methanol at $95^{\circ}C$ for 6 hours, however, nitrite radical scavenging activities were extremely increased at $75^{\circ}C$ for 12 hours by 97.4%. At $200mg{\cdot}L^{-1}$ and $400mg{\cdot}L^{-1}$ methanol extracting concentration, the hyperplasia of lung cancer cells (Calu-6) and stomach cancer cells (SNU601) were effectively inhibited over 90%. Consequently, it was assumed that Ligularia fischeri was a functional vegetable with a higher physiological activities. Making the processed foods, it had better make the extracts from Ligularia fischeri with methanol at $95^{\circ}C$ for 6 hours.