• Journal of the Korean Chemical Society
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• v.41 no.6
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• pp.304-312
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• 1997

Acetolactate synthase(ALS) is the common enzyme in the biosynthetic of valine, leucine, and isoleucine, and is the target of several classes of structually unrelated herbicides, including sulfonylureas, imidazolinones, and triazolopyrimidines. In an effort to develop new and desirable herbicides, we have synthesized 4,6-dimethoxypyrimidine derivatives, and examined their inhibitory activities on pea ALS. The most active compound was found to be K11570 and $IC_{50}$ value for K11570 was 0.2 ${\mu}M.$ The inhibition of pea ALS by K11570 was biphasic, showing increased inhibition with incubation time. The K11570 showed mixed-type inhibition with respect to substrate pyruvate. Dual inhibition analysis of K11570 versus sufonylurea herbicide Ally and feedback inhibitor leucine revealed that three inhibitors were competitive for binding to ALS. The arginine modified enzyme showed decreased inhibition by K11570, sufonylurea Ally, and leucine, in constrast to, tryptophan modification did not affect on the sensitivity of ALS to the inhibitors.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.10
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• pp.31-36
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• 1999

The $CaSiN_2:Eu$ and $CaSiN_2:Tb$ phosphors were synthesized and analyzed to develop new nitride compound phosphors. $Ca_3N_2$, $Si_3N_4$ and $EuF_3$(or $TbF_3$) powders were mixed, cold-pressed, and sintered to synthesize $CaSiN_2:Eu$ and $CaSiN_2:Tb$ phosphors. Photoluminescence(PL) and electroluminescence(EL) characteristics of the synthesized phosphors were measured and found to be similar to general emission spectra of 뗘 and Tb ion, respecticely. Threshold voltage($V_{th)$) and luminance of the $CaSiN_2:Eu$ TFEL device fabricated by sputtering were 90 V and 1.62 $cd/m^2$ at 280 V, respectively. The charge-voltage(Q-V) and transferred charge-phosphor field($Q_t-F_p$) characteristics of the TFEL devices were also measured.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05a
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• pp.189-192
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• 2004

To improvement life-time of the organic light emitting diodes(OLEDs). We investigate the inorganic composite film based on MgO and $SiO_2$ to protect from the moisture and oxygen. The inorganic composite films are added the base materials to the co-operate materials using the mixed process and it is deposited on plastic substrate by e-beam evaporator. In order to analyze as kinds of inorganic materials, Water Vapor method of Transmission Rate (WVTR) and Oxygen Transmission Rate (OTR) are measured by Permatran equipment(MOCON Corp.). For comparison. an MgD- and $SiO_2$-based composite film has lower values of WVTR and OTR than inorganic composite/compound films of ones. The results obtained here shows that this film is suitable for passivation layer to extend the life-time of OLEDs.

• Fashion & Textile Research Journal
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• v.10 no.1
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• pp.22-29
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• 2008

In this study, it is investigated the types and the compounding method of flower patterns and the uses of flower patterned fabrics in Chosun Dynasty. Research was done through the references of exhumed clothing during 16-17th century. Our ancestors had used the various flower patterns based on Buddhism, Taoism and Confucianism onto the fabrics. The flower patterns on the fabrics were expressed with the other patterns such as treasure patterns, letter patterns or bird patterns. And the flower patterns symbolized the various good meanings such as longevity, integrity and prosperity etc. In the order of the percentage, the types of the flower patterns were shown Lotus(27.31%), Arabesque(26.85%), Japanese apricot(14.81%), Peony(8.79%), Flowering plants(6.94%), Chrysanthemum(6.01%), Pomegranate(2.31%) patterns and so on. Especially the Lotus pattern was shown up most frequently. That of shape was designed as blooming(開花), full bloom(滿開) and the side of flower(側面). By the compounding method, the compound types mixed with the other patterns were used much more than the individual types composed by its own pattern. The flower patterns were used a lot in Jeogori(Jacket) regardless of the ganders and in men's Po(coat) including Cheollik(天翼), Dappo(胡), Jeonbok(戰服), Dahnryoung(團領), etc. Also contrary to these days, the flower patterned fabrics had come out in the shrouds. Judging from these facts, our ancestors wished that the meaning of the immortal life was included in the flower pattern.

• Journal of Korean Society on Water Environment
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• v.32 no.6
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• pp.670-699
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• 2016

In this study, 16 antibiotics were selected from among the top 30 veterinary antibiotics sold in South Korea in 2014, as well as from among the pharmaceuticals targeted by EPA method 1694, in order to review analytical methods for the detection of trace levels of antibiotics in environmental samples: surface water, soils, animal origin foods, and manures. LC-MS/MS was heavily used. In the chromatography for the detection of the selected antibiotics, the $C_{18}$ column was mostly used at the temperature of $30{\sim}40^{\circ}C$. Water and methanol/acetonitrile were commonly chosen as a nonpolar and a polar mobile phase, respectively. Gradient elution was applied to separate multiclass antibiotics. Volatile additives, such as formic acid, acetic acid, and ammonium acetate were mixed with the mobile phase to improve the ionization efficiency of analytes and the sensitivity in MS detection. Electrospray ionization (ESI) was widely used in the LC-MS/MS and positive ionization was preferred to determine the selected antibiotics. A protonated $[M+H]^+$ molecule was selected as a precursor ion, and its two transitions were analyzed, one for quantitative measurement and the other for confirmation. This study reviewed linearity of the calibration curve, recovery, repeatability, method detection limits (MDLs), and method quantification limits (MQLs) for each target compound used to validate the developed analytical methods.

• Journal of Distribution Science
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• v.16 no.2
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• pp.53-65
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• 2018

Purpose - The purpose of this study is to investigate the effect of gamma - irradiation on the effluent from food distribution in the large agricultural and marine products market. This study will contribute to the distribution process as well as the agricultural and fishery distribution facilities. Research design, data, and methodology - In order to reduce the odor, the smell was examined in the anaerobic digestion process by irradiating gamma rays to the wastewater of mixed food discharged from a large restaurant. An odor determination panel list was constructed to determine if the odor was present in the air dilution drainage and the odor concentration was analyzed by instrumental analysis. Results - It was confirmed that the sulfur content increased gradually from 3 months. Ammonia decreased from 33.57ppm at the initial measurement to 4.12 ppm at the end of the experiment. Methane production was highest at 100kGy when exposed to gamma rays of 0-200kGy at pH 12. In other words, it is considered that gamma irradiation doses are most effective at 100kGy and are suitable for large capacity wastewater treatment facilities in terms of economic feasibility. Conclusions - In pre-treatment of compound food wastewater, gamma irradiation is most cost effective when examined at 100kGy. The economic efficiency of the pre-treatment method by gamma irradiation is much higher than the wastewater treatment in the large-scale agricultural and marine products distribution market.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.5
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• pp.512-522
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• 2008

Ammonia is a major compound of odor in livestock house. To enhance the performance of ammonia oxidation (decomposition). the gas-liquid, two phase photocatalytic oxidation system was designed and prepared in this study. Commercial P-25 as $TiO_2$ catalyst was used for ammonia decomposition. V/P-25 catalyst prepared by sol gel method was also used for the removal of by-producted $NO_x$ in $NH_3$ oxidation reaction. When $TiO_2$ was used as a photocatalyst, the conversion to $N_2$ in ammonia decomposition reached above 90% until 200hr (The air flow rate of 4L/min with the ammonia concentration up to 25ppm.). However, considerable amounts of NO and $NO_2$ were formed as a result of $NH_3$ oxidation (as a by-product). Therefore, we added Vanadia impregnated $TiO_2$(P-25) catalyst for the removal of $NO_x$ at the end of reaction trail. The results of a pilot-scale operation were successful to achieve the simultaneous removal of $NH_3\;and\;NO_x$ about 81 and 87%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1635-1641
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• 2008

This study investigated the effects of solid-state fermentation of a compound pig feed on its microbial and nutritional characteristics as well as on pig performance and nutrient digestibility. A mixed culture containing Lactobacillus fermentum, Saccharomyces cerevisae and Bacillus subtilis was used for solid-state fermentation and solid-state fermented feed samples were collected on days 0, 1, 2, 3, 5, 7, 10, 15, 20 and 30 for microbial counts and chemical analysis. Lactic acid bacteria increased rapidly during the first three days of fermentation and then slowly declined until day 10 and, thereafter, the counts were maintained at about 6.7 log cfu/g for the duration of the fermentation period. Enterobacteria also increased during the first two days, and then fell below the detectable level of the analysis (3.0 log cfu/g). The pH of the fermentation substrate declined from 6.1 at the start of fermentation to 5.7 by day 30. The water-soluble protein content increased from 8.2 to 9.2% while the concentration of acetic acid increased from 16.6 to 51.3 mmol/kg over the 30-day fermentation. At the end of the 30-day fermentation, the solid-state fermented feed was used in a pig feeding trial to determine its effects on performance and nutrient digestibility in growing-finishing pigs. Twenty crossbred barrows ($14.11{\pm}0.77kg\;BW$) were allotted into two dietary treatments, which comprised a regular dry diet containing antibiotics and a solid-state fermented feed based diet, free of antibiotics. There was no difference due to diet on pig performance or nutrient digestibility. In conclusion, solid-state fermentation resulted in high counts of lactic acid bacteria and low counts of enterobacteria in the substrate. Moreover, feeding a diet containing solid-state fermented feed, free of antibiotics, can result in similar performance and nutrient digestibility in growing-finishing pigs to a regular diet with antibiotics.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.337-342
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• 2004

A non-ionic surfactant, Tween 80 has been known to exert a number of positive effects on degradative enzymes in in vitro aerobic and anaerobic microbial cultures. An experiment was conducted to examine effects of supplementation of Tween 80 on ruminal fermentation and nutrient digestibility of Hanwoo steers. The experiment was designed as a $3{\times}3$ Latin square with duplication and six Hanwoo steers with rumen cannulae, average weight 497 (SE 61.1) kg. For the experiment the animals were given a basal diet consisting of rice straw and compound feed mixed at 4:6 ratio. The three experimental treatments were (1) the basal diet, supplemented with (2) 5 g/d Tween 80 and (3) 10 g/d Tween 80. Ruminal pH was significantly (p<0.05) affected by Tween 80 supplementation at 6 h after feeding. Increasing supplementation levels of Tween 80 linearly increased the total VFA concentration. CMCase activity by the 10g/d supplementation of Tween 80 were significantly increased (p<0.05) by 24.4% compared with that of control. Digestibility of crude fiber was significantly increased (p<0.05) in Hanwoo steers fed the diet supplemented with 10 g/d Tween 80 compared with those of control, whilst digestibility of ether extract (EE) was linearly increased by increasing Tween 80 supplementation level (p<0.05). In other nutrient components, their digestibilities of Hanwoo fed diets supplemented with Tween 80 tended to increase. It is concluded that Tween 80 has a potential for industrial application as a feed additive to improve ruminant production.

• Progress in Superconductivity
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• v.3 no.1
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• pp.23-27
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• 2001

We have investigated the mixed-state magnetoresistance of high quality c-axis-oriented MgB2 thin film for magnetic field from 0.5 T to 5.0 T, applied normal to ab-plane. The temperature dependence of magnetoresistance was well described by vortex glass and fluctuation theories for different temperature regimes. We observed glassy exponent of v(z-1)~3 and upper critical field of $H_{c2}$(0)~35 T, which is consistent with previous data obtained from direct $H_{c2}$(0) measurements. Interestingly, the thermally activated flux flow region was observed to be very narrow, suggesting that the pinning strength of this compound is very strong. This finding is closely related to the recent reports that the bulk pinning is dominant in $MgB_2$and the critical current density of $MgB_2$ thin film is very high, comparable to that of cuprate superconductor. The present results further suggest that $MgB_2$is beneficial to technical applications.ons.