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Residue Analysis of Quinclorac in Soil by Supercritical Fluid Extraction and Fluorogenic Derivatization Coupled with High Performance Liquid Chromatography (초임계추출과 형광유도체를 이용한 HPLC 에서의 Quinclorac 의 토양중 잔류분석)

  • Kim, Yong-Whan
    • Applied Biological Chemistry
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    • v.40 no.5
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    • pp.442-446
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    • 1997
  • A new analytical method was developed by HPLC after supercritical fluid extraction and fluorogenic derivatization for the determination of quinclorac (3,7-dichloro-8-quinoline carboxylic acid) in soil. The graminicide quinclorac was extracted from soil by supercritical fluid extraction. Supercritical carbon dioxide at 7000 psi $(80^{\circ}C)$ modified with 30% of methanol extracted quinclorac from soil samples at the level of $0.1ng\;g^{-1}$ with 96% recovery. Extracted quinclorac was determined by HPLC as a fluorescent derivative. Derivatization was made with 4-bromomethyl-7-methoxycoumarin (4-Br-Mmc) using 18-crown-6-ether as a catalyst. The conversion was completed within 30 min and the limit of detection was 0.5 ppb to prove that the procedure could be used in the residue analysis of the pesticides containing carboxylic acid group.

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Study on Possibility of PrBaMn2O5+δ as Fuel Electrode Material of Solid Oxide Electrolysis Cell (이중 페로브스카이트 촉매 PrBaMn2O5+δ의 고온전기분해조(Solid Oxide Electrolysis Cell) 연료극 촉매로 적용 가능성에 대한 연구)

  • Kwon, Youngjin;Kim, Dongyeon;Bae, Joongmyeon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.4
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    • pp.491-496
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    • 2017
  • The hydrogen($H_2$) is promising energy carrier of renewable energy in the microgrid system such as small village and military base due to its high energy density, pure emission and convenient transportation. $H_2$ can be generated by photocatalytic water splitting, gasification of biomass and water electrolysis driven by solar cell or wind turbine. Solid oxide electrolysis cells(SOECs) are the most efficient way to mass production due to high operating temperature improving the electrode kinetics and reducing the electrolyte resistance. The SOECs are consist of nickel-yttria stabilized zirconia(NiO-YSZ) fuel electrode / YSZ electrolyte / lanthanum strontium manganite-YSZ(LSM-YSZ) air electrode due to similarity to Solid Oxide Fuel Cells(SOFCs). The Ni-YSZ most widely used fuel electrode shows several problems at SOEC mode such as degradation of the fuel electrode because of Ni particle's redox reaction and agglomeration. Therefore Ni-YSZ need to be replaced to an alternative fuel electrode material. In this study, We studied on the Double perovskite $PrBrMnO_{5+{\delta}}$(PBMO) due to its high electric conductivity, catalytic activity and electrochemical stability. PBMO was impregnated into the scaffold electrolyte $La_{0.8}Sr_{0.2}Ga_{0.85}Mg_{0.15}O_{3-{\delta}}$(LSGM) to be synthesized at low temperature for avoiding secondary phase generated when it exposed to high temperature. The Half cell test was conducted at SOECs and SOFCs modes.

Characterization studies of digital x-ray detector based on mercuric iodide (Mercuric iodide 기반의 디지털 X-선 검출기의 특성 연구)

  • Cho, Sung-Ho;Park, Ji-Koon;Choi, Jang-Yong;Suck, Dae-Woo;Cha, Byung-Yul;Nam, Sang-Hee;Lee, Byum-Jong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.11a
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    • pp.392-395
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    • 2003
  • For the purpose of digital x-ray imaging, many materials such as $PbI_2$, $HgI_2$, TlBr, CdTe and CdZnTe have been under development for servaral years as direct converter layer. $Hgl_2$ film detector have recently been shown as one of the most promising semiconductor materials to be used as direct converters in x-ray digital radiography. This paper, the $HgI_2$ films are deposited on conductive-coated glass by screen printing, in which $HgI_2$ powder is embedded in a binder and solvent, and the slurry is used to coat the conductive-coated glass. We investigated electrical characteristic of the fabricated $HgI_2$ films. The x-ray response to radiological x-ray generator of 70Kvp using the current integration mode will be reported for screen printing films. These results indicate that $HgI_2$ detectors have high potential as new digital x-ray imaging devices for radiography.

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A study on the changes of carcass muscle distribution in the high quality meat production of Hanwoo steers in Kyungnam (경남지역 거세한우의 고급육 생산을 위한 도체 근육부위별 분포도 차이에 대한 연구)

  • Kim, Cheol-Ho;Kim, Taeg-Seog;Kim, Chung-Hui
    • Korean Journal of Veterinary Service
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    • v.43 no.2
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    • pp.45-52
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    • 2020
  • A grading system is implemented to evaluate the meat quality of Hanwoo. In the grading system, grade 1++A is the highest grade. Livestock farms breed Hanwoo with good quality feed in order to obtain the highest grade. In this process, the content ratios of muscles in individual regions can be changed. To find out the muscle distribution ratios of Hanwoo steers, grade 1A, 1+A, and 1++A Hanwoo steers were compared with grade 1+A Hanwoo female. Grade 1A Hanwoo steers had higher ratios of shank (SK), brisket and flank (BF), neck chain (NC), and inside skirt (IS) meats and a lower ratio of striploin (SL) meat compared to grade 1+A Hanwoo feamle. Grade 1++A Hanwoo steers had higher ratios of neck (NK) and loin (LN) meats and lower ratios of inside skirt (IS), tenderloin (TL), top round (TR), eye round (ER), bottom round (BR), bottom sirloin triangle (BST), and knuckle (K) meats compared to grade 1+A Hanwoo steers. In comparison between grade 1A and 1++A Hanwoo steers, the ratio of shank (SK) was significantly lower in higher quality meats. If the changes are continuously studied to improve the process so that the ratios of partial meats of the regions highly preferred by consumers can increase, it will contribute to increases in the incomes of livestock farms and enable Hanwoo to grow into a global brand.

A Study on the Shrinkage of Silk Fabric by $Ca(NO_3){_2}$ Solution

  • Choi, Se-Min;Shin, Yu-Ju;Kim, Jong-Jun;Jeon, Dong-Won
    • Journal of Fashion Business
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    • v.13 no.3
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    • pp.136-148
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    • 2009
  • The phenomenon of the shrinkage of silk fibers induced by inorganic salts including LiBr, $Ca(NO_3){_2}$, and $CaCl_2$, has been studied up to the present as one of the finishing methods of silk. It is expected that the shrinkage phenomenon may greatly contribute to the realization of the high sensibility of silk fibers. Especially the shrinkage enables the expression of three-dimensional appearance of silk fabrics along with the improvements in dimensional stability, resilience in stretching, and comfort. Numerous theoretical studies on the contraction phenomenon by $Ca(NO_3){_2}$ have been conducted so far. These studies have focused mostly on the silk fibers. It is difficult to find studies on silk fabrics. The negative aspects of the finishing are such as strength drop, yellowish discoloration, and fiber damage. These should also be considered as well as the positive aspects. In this study, the phenomenon of salt shrinkage is diversely reviewed by applying $Ca(NO_3){_2}$ solution for the silk fabrics as objects. The changes in the air permeability, thickness, and color were investigated with focus on the shrinkage of the silk fabrics according to the changes in treatment conditions. Some findings from this study are as follows: Within short period of time at the initiation of salt shrinkage, the salt shrinkage proceeds effectively. In the case of concentration of 47.4%, or 46.3% of $Ca(NO_3){_2}$ solution, appropriate treatment time seems to be 20seconds, or $2{\sim}8$minutes, respectively. Excessive shrinkage is obtained when lower liquor ratio is adopted. As a result, the condition is acting extremely disadvantageously against the thickness and yellow discoloration aspects.

Molecular identification and expression analysis of bactericidal permeability-increasing protein/ LPS-binding protein (BPI/LBP) from Black rockfish Sebastes schlegeli

  • Kwon, Mun-Gyeong;Kim, Ju-Won;Park, Myoung-Ae;Hwang, Jee-Youn;Park, Hyung-Jun;Baeck, Gun-Wook;Park, Chan-Il
    • Journal of fish pathology
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    • v.23 no.3
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    • pp.323-334
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    • 2010
  • Bactericidal/permeability-increasing protein (BPI) and lipopolysaccharide-binding protein (LBP) are important components of the mammalian innate defence system against Gram-negative infections. The BPI/LBP cDNA was identified from the black rockfish ConA/PMA or LPS stimulated leukocyte cDNA library. The full-length BR-BPI/LBP cDNA was 2118 bp long and contained an open reading frame (ORF) of 1422 bp that encoded 473 amino-acid residues. The 5' UTR had a length of 57 bp, and the 3' UTR 639 bp. The molecular weight and theoretical isoelectric point (pI) values were calculated 51.4 kDa and 9.72, respectively. Compared with other known BPI or BPI/LBP peptide sequences, the most conserved regions of the black rockfish BPI/LBP peptide were found to be the BPI1 N-terminal, BPI2 C-terminal domains and a LPS binding domain. Phylogenetic analysis based on the deduced amino acid sequence revealed a homologous relationship between the BPI/LBP sequence of black rockfish and that of other teleosts. The black rockfish BPI/LBP gene was predominantly expressed in the PBLs, head kidney, trunk kidney and spleen. The expression of the black rockfish BPI/LBP molecule was induced in the peripheral blood leukocytes (PBLs) from 1 to 24 h following LPS stimulation, with a peak at 12 h post-stimulation.

Cinnamic Acid Derivatives V. the Kinetics and Mechanism of the Hydrolysis of Cinnamenylisophorone Derivatives (신남산 유도체 V. Cinnamenylisophorone 유도체의 가수분해 반응에 대한 메카니즘과 그 반응속도론적 연구)

  • Lee, Ki-Chang;Yun, Cheol-Hun;Ryu, Jung-Wook;Lee, Seok-Woo;Jung, Duk-Chal
    • Journal of the Korean Applied Science and Technology
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    • v.8 no.2
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    • pp.161-167
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    • 1991
  • The kinetics of hydrolysis of cinnamenylisophorone derivatives (${rho}-H,\;{rho}-Br,\;P-Cl,\;{rho}-OCH_3$) was investigated using ultraviolet spectrophotometry in 20%(v/v) dicxane-$H_2O$ at 25$^{\circ}C$. A rate equation which can be applied over wide pH range (pH $1.0{\sim}13.0$) was obtained. In order to investigate the substituent effects on cinnarnenylisophorone derivatives, Hammett constant was plotted. As the result, the rate of hydrolysis of cinnamenylisophorone derivatives was facilitated by electron donating group. Final products of the hydrolysis were benzaldehyde and isophorone, From the measurement of reaction rate constant according to pH changes, substituent effect, and final products, it was found that the hydrolysis of cinnarnenylisophorone derivatives was initiated by the neutral $H_2O$ molecule which does not dissociated at below pH 9.0, and in the range of pH $9.0{\sim}11.0$ this reaction occurs by $H_2O$ or hydroxide ion competitively, but proceeded by the hydroxide ion above pH 11.0. On the basis of this kinetic study, the reaction mechanism of the hydrolysis of cinnamenylisophorone derivatives was proposed.

Study on the Concentration of Some Trace Elements in the Diet in Korea

  • Lee, Chul;Kim, Nak-Bae;Lee, Ihn-Chong
    • Nuclear Engineering and Technology
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    • v.8 no.4
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    • pp.195-201
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    • 1976
  • The present levels for the contents of mercury, arsenic, bromine, copper, manganese and potassium in various groups of foodstuffs are evaluated and compared with data given previously by others. On the basis of the data for the levels, the average daily intakes have teen estimated to be 2.0$\times$10$^1$$\mu\textrm{g}$ for Hg, 3.2$\times$10$^2$$\mu\textrm{g}$ for As, 2.3$\times$10$^3$$\mu\textrm{g}$ for Br, 2.5$\times$10$^3$$\mu\textrm{g}$ for Cu, 6.8$\times$10$^3$$\mu\textrm{g}$ for Mn and 2.1$\times$10$^{6}$ $\mu\textrm{g}$ for K. For this purpose, the data reported as a result of the 1974 National Nutrition Survey have been used.

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Study into prosodic morphological analysis in Korean and Standard Chinese partial reduplication and contrastive analysis using optimality theory (한국어와 표준 중국어 부분 중첩 의성·의태어에 대한 운율 형태론적 분석의 문제와 최적성 이론적 분석을 통한 대조 분석)

  • Chang, Jae-Woong
    • Cross-Cultural Studies
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    • v.49
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    • pp.275-301
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    • 2017
  • Based on the previous analysis by Wanghongjun(2008), this paper applies Optimality Theory (OT) to the field of partial reduplication in Korea to increase its scientific validity. Toward this end, I propose an alternative analysis of Korean partial reduplication, applied as a single process of prefixation. Reduplicated words by prefixation are divided into two types: with a heavy syllable of the stem, and another with the stem. The two types of partial reduplication are closely related by the sound features. In addition, I discussed Chinese partial reduplication from a prefixation perspective within the framework of OT and performed contrastive analysis of Korean and Standard Chinese processes of reduplication by focusing on constrained rankings. As a result, the alternative analysis showed a systematic relationship among the reduplicated words in Korean and Standard Chinese. Lastly, I explained that the coronal /t/ and liquid /l/ have a special functional hierarchy in both languages. This study can be re-explained based on the framework of OT according to a few major constraints, involving MAX-BR, MAX-IO. Their rankings show the adequacy of analysis.

Antioxidant effects of kimchi supplemented with black raspberry during fermentation protect against liver cirrhosis-induced oxidative stress in rats

  • Ryu, Eun-Hye;Yang, Ji-Su;Lee, Min-Jung;Kim, Sung Hyun;Seo, Hye-Young;Jung, Ji-Hye
    • Nutrition Research and Practice
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    • v.13 no.2
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    • pp.87-94
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    • 2019
  • BACKGROUND/OBJECTIVES: Oxidative stress is a major effector of various diseases; accordingly, antioxidants are frequently ingested in order to prevent or alleviate disease symptoms. Kimchi contains various natural antioxidants, and it is known that the functional activity varies depending on the ingredients and fermentation state. Black raspberries (BR) contain various bioactive compounds with antioxidant effects. This study investigated the antioxidant and liver-protection effects of kimchi supplemented with black raspberry juice powder (BJP). MATERIALS/METHODS: BJP-added kimchi (BAK; at 0.5%, 1%, and 2% concentrations of BJP) and control (without BJP) were prepared and fermented at $4^{\circ}C$ for 4 weeks. Changes in the antioxidant effects of BAK during fermentation were investigated. In addition, the protective activity of BAK against oxidative stress was investigated in a liver cirrhosis-induced animal model in vivo. RESULTS: BAK groups showed the acidity and pH of optimally ripened (OR) kimchi at 2 weeks of fermentation along with the highest lactic acid bacterial counts. Additionally, BAK groups displayed a higher content of phenolic compounds and elevated antioxidant activities relative to the control, with the highest antioxidant effect observed at 2 weeks of fermentation of OR 1% BAK. After feeding the OR 1% BAK to thioacetamide-induced liver cirrhosis rats, we observed decreased glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities and elevated superoxide dismutase activity. CONCLUSIONS: These findings showed that the antioxidant effects of OR BAK and feeding of OR 1% BAK resulted in liver-protective effects against oxidative stress.