• Title/Summary/Keyword: Separation flow

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Simultaneous Determination of Hesperidin and Glycyrrhizin in Pyungwi-san by HPLC/DAD (HPLC-DAD를 이용한 평위산 중의 Hesperidin 및 Glycyrrhizin의 동시분석법 확립)

  • Lee, Mi-Kyeong;Choe, Ok-Gyeong;Park, Jin-Ho;Cho, Jung-Hee;Kim, Do-Hoon;Baek, Ju-Hyun;Kim, Hyo-Jin;Lee, Ki-Yong;Kim, Sang-Du;Kim, Young-Choong;Sung, Sang-Hyun
    • Korean Journal of Pharmacognosy
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    • v.39 no.3
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    • pp.199-202
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    • 2008
  • A high performance liquid chromatographic (HPLC) method for the simultaneous determination of hesperidin and glycyrrhizin was established for the quality control of traditional herbal medicinal preparation, Pyungwi-san (PWS). Separation and quantification were successfully achieved with a Waters XTerra RP18 column ($5{\mu}m$, 4.6 mm I.D. ${\times}$ 150 mm) by gradient elution of a mixture of acetonitrile and water containing 0.03% phosphoric acid (pH 2.03) at a flow rate of 1.0 ml/min. The diode-array UV/vis detector (DAD) was used for the detection and the wavelength for quantification was set at 230 nm. The presence of hesperidin and glycyrrhizin in this extract was ascertained by retention time, spiking with each authentic standard and UV spectrum. All four compounds showed good linearity $(r^2>0.995)$ in a relatively wide concentration ranges. The R.S.D. for intra-day and inter-day precision was less than 7.0% and the limits of detection (LOD) were less than 60 ng. The mean recovery of each compound was 99.0-105.6% with R.S.D. values less than 4.0%. This method was successfully applied to the determination of contents of hesperidin and glycyrrhizin in three commercial products of PWS. These results suggest that the developed HPLC method is simple, effective and could be readily utilized as a quality control method for commercial PWS products.

Effect of Turbid Water on Fishes in the Streams of Imha Reservoir (임하호 유입지천에 서식하는 어류에 미치는 탁수의 영향)

  • Yu, Sam-Hwan;Kim, Jeong-Sook;Shin, Myung-Ja;Lee, Jong-Eun;Seo, Eul-Won
    • Journal of Life Science
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    • v.19 no.10
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    • pp.1410-1416
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    • 2009
  • The present study aims to examine the effect of turbid water on fishes in streams which branch into a turbid water area (Yeongyang-gun) and a non-turbid water area (Cheongsong-gun), and finally flow into the Imha reservoir. In a comparison of water quality, the chemical status of the water showed higher pH, DO and SS in the turbid water area than in the non-turbid water area. Also, high density of clay minerals such as vermiculite (V) and illite (I), which is from clay mineral leakage during rainfall, was detected in turbid water, resulting in an increase of turbidity. Fishes inhabiting the turbid water showed irregular spaces in gill lamella, cell separation, edema, and clubbing in epithelial tissues. Also, the gill surface showed roughness and plenty of muddy debris substances inside the gills. The Bowman's space was expanded because of contraction of the glomerulus in the Bowman's space of the kidney tissues. Antioxidant enzymes such as SOD, CAT, GPX, and GST showed higher activities in the specific tissues, muscles and kidney, of fishes living in turbid water than in the non-turbid area. We suggested that; first, the antioxidant activities were increased due to removal of harmful radicals generated in fish bodies in the turbid water area, second, long-time exposure of these histological changes in the tissues might have induced secondary lesion accompanying the inaccurate physiological constancy of fishes.

A Study on the Elution Mechanism of Ni(II)-Isonitrosoethylacetoacetate Imine Chelates by Reversed Phase High Performance Liquid Chromatography (역상 액체 크로마토그래피에 의한 Ni(II)-Isonitrosoethylacetoacetate Imine 유도체 킬레이트의 용리 메카니즘에 관한 연구)

  • Kim In-Whan;Choi Gang-Yeol;Lee Man-Ho;Kang Chang-Hee;Lee, Won
    • Journal of the Korean Chemical Society
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    • v.36 no.5
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    • pp.697-708
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    • 1992
  • Liquid Chromatographic behavior of Ni(II) in Isonitrosoethylacetoacetate Imine(IEAA-NR), Ni(IEAA-NH)(IEAA-NR)(R = H, CH_3, C-2H_5, n-C_4H_9, C_6H_5-CH_2) chelates were investigated by reversed-phase HPLC on Micropak MCH-5 column using methanol/water as mobile phase. The optimum conditions for the separation of Ni(IEAA-NH)(IEAA-NR) chelates were examined with respect to the effect of the flow rate, sample solvent, mobile phase strength and column temperature. It was fo$und that metal chelates were properly eluted in an acceptable range of capacity factor value(0{\le}logk'{\le}1). The dependence of the logarithm of capacity factor (k') on the volume fraction of water in the binary mobile phase as well as on the liquid-liquid extraction distribution ratio (Dc) in methanol-water/n-alkane extraction system showed the good linearties, and the dependence of the logarithm of capacity factor (k') on the column temperature and on the enthalpy exhibited the good linearties, and the compensation temperature ({\beta}) from the slope was 773.47{\circ}K. It was suggested that the retention of metal chelates was largely affected by the hydrophobic effect.

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Bibliographical study on the Jiu Qi(九氣) shown at Ju Tong Lun(擧痛論) in Shao Wen(素問) Huang Ti Nei Ching(黃帝內經) (${\ll}$소문(素問).거통론(擧痛論)${\gg}$에 나타난 구기(九氣)에 대(對)한 고찰(考察))

  • Kim, Bo-Kyung
    • Journal of Oriental Neuropsychiatry
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    • v.11 no.1
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    • pp.145-167
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    • 2000
  • Jiu Qi(九氣) was shown at Ju Tong Lun(擧痛論) in Shao Wen(素問) Huang Ti Nei Ching(黃帝內經), and is nine important factors that affect the function of human body. Jiu Qi concludes endogenous, exogenous, non-endo-exogenous factors. I do the bibliographical study on the Jiu Qi, the results were as follows; 1. The Qi of Jiu Qi has two opposite meanings. one is genuine vital energy(正氣), and the other is the factors causing abnormal state in vital energy. Jiu Qi is nine factors concluding coldness-heat(exogenous factors). six emotional factors(endogenous factor), overworking(non -endo-exogenous factor). 2. Anger may lead to abnormal rising of vital energy. Anger causes Qi of the liver to go perversely upward, and perverted flow of exuberant Qi of the liver lead to dysfunction of the spleen, so resulted in hematemesis, diarrhea, indigestion. 3. Joy can promote the harmony of vital energy and blood, so do the circulation of nutrient and defensive energy in physiological state. But an excessive joy may lead to the sluggishness of vital energy. 4. The lung keeps the pathway of air unconstructed, disseminates vital energy, cleanses the inspired air and keeps vital energy flowing downward. Sorrow affects on the function of the lung and the heart, so could result in obstruction of the circulation of nutrient and defensive energy. An excessive sorrow after stagnation may lead to the consumption of vital energy. 5. Fear makes vital energy and essence of the kidney sink to inward and downside, makes Yang-Qi can't go upward, so causes obstruction of triple wanner. An excessive fear can obstructs the ascending of Yang-Qi, so may lead to the abnormal falling of vital energy. 6. Coldness makes the sweat pore be contracted, so obstructs the circulation of triple warmer, causes sluggishness of defensive energy or Qi of the internal organ. 7. Heat makes the sweat pore be open, much amount of sweat is excreted with Yang-Qi, defensive energy, vital energy. Heat may consume vital energy. 8. Sudden fright affects on spirits of the heart and liver, causes disorder of the mental faculties and separation of blood and vital energy. Fright may lead to disorder of Qi. 9. Overwork concludes overfatigue and exhaustion caused by intemperance in sexual life. Overwork renders vital energy consumed, and hence results in lassitude and listlessness. 10. Thinking affects on the function of the heart and the spleen. Over thinking may lead to depression of vital energy. Through the bibliographical study on Jiu Qi, I got smallest amount of it, and this must be more investigated correlating with clinical study.

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The development and validation of a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) procedure for the determination of fluoroquinolones residues in chicken muscle using modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method

  • Park, Sunjin;Kim, Hyobi;Choi, Byungkook;Hong, Chung-Oui;Lee, Seon-Young;Jeon, Inhae;Lee, Su-Young;Kwak, Pilhee;Park, Sung-Won;Kim, Yong-Sang;Lee, Kwang-jick
    • Korean Journal of Veterinary Service
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    • v.42 no.4
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    • pp.289-296
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    • 2019
  • A novel rapid procedure with liquid chromatography tandem mass spectrometry (LC-MS/MS) detection has been developed by changing various conditions including sample preparation such as QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) methodology. This work has been involved the optimization and validation of detection method for fluoroquinolones which are widespread used in livestock especially in the chicken. Five grams of homogenized chicken muscle were extracted with QuEChERS EN and acetonitrile containing 5% formic acid and cleaned with anhydrous magnesium sulfate and C18 sorbent. The separation was performed on Acquity UPLC HSS T3 (2.1 mm×100 mm, 1.8 ㎛) column. The mobile phase A and B were composed of water containing 0.1% formic acid and acetonitrile containing 0.1% formic acid, respectively. Flow rate was 0.25 mL/min and column temperate was 40℃. LC-MS/MS with multiple reaction monitoring has been optimized for ten fluoroquinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, marbofloxacin, norfloxacin, ofloxacin, orbifloxacin, pefloxacin and sarafloxacin). The method developed in this study has been presented good linearity with correlation coefficient (R2) of 0.9971~0.9998. LOD and LOQ values ranged from 0.09 to 0.76 ppb and from 0.26 to 2.29 ppb, respectively. The average recoveries were from 77.46 to 111.83% at spiked levels of 10.0 and 20.0 ㎍/kg. Relative standard deviation (%) ranged 1.28~11.90% on intra-day and 3.10~8.38 % on inter-day, respectively. This analysis method was applicable to the livestock residue laboratories and was expected to be satisfactory for the residue surveillance system.

Aerodynamic Load Analysis of a Floating Offshore Wind Turbine Considering Platform Periodic Motion (플랫폼의 주기 운동을 고려한 부유식 해상 풍력터빈의 공력 성능 해석)

  • Kim, Youngjin;Yu, Dong Ok;Kwon, Oh Joon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.5
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    • pp.368-375
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    • 2018
  • In the present study, aerodynamic load analysis for a floating off-shore wind turbine was conducted to examine the effect of periodic platform motion in the direction of 6-DOF on rotor aerodynamic performance. Blade-element momentum method(BEM) was used for a numerical simulation, the unsteady airload effects due to the flow separation and the shed wake were considered by adopting a dynamic stall model based on the indicial response method. Rotor induced downwash was estimated using the momentum theory, coupled with empirical corrections for the turbulent wake states. The periodic platform motions including the translational motion in the heave, sway and surge directions and the rotational motion in the roll, pitch and yaw directions were considered, and each platform motion was applied as a sinusoidal function. For the numerical simulation, NREL 5MW reference wind turbine was used as the target wind turbine. The results showed that among the translation modes, the surge motion has the largest influence on changing the rotor airloads, while the effect of pitch motion is predominant for the rotations.

Thin-Film Composite (TFC) Membranes with Hydrophilic Ethyl Cellulose-g-poly(ethylene glycol) (EP) Substrates for Forward Osmosis (FO) Application (친수성을 가지는 에틸셀룰로스-폴리에틸렌글리콜 가지형 고분자의 정삼투 복합막 지지층으로의 응용)

  • Yu, Yun Ah;Kim, Jin-joo;Kang, Hyo;Lee, Jong-Chan
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.510-518
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    • 2016
  • Ethyl cellulose-g-poly(ethylene glycol) (EP) was synthesized by esterification of carboxylic acid functionalized methoxy polyethylene glycol (MPEG-COOH) with ethyl cellulose (EC) in order to develop a hydrophilic substrate for thin-film composite (TFC) membrane in a forward osmosis (FO) system. A porous EP substrate, fabricated by a non-solvent induced phase separation method, was found to be more hydrophilic than the EC substrate due to the presence of polyethylene glycol (PEG) side chains in the EP. Since the EP substrate exhibits smaller water contact angles and higher porosity, the structural parameter (S) of TFC-EP is smaller than that of TFC-EC, indicating that internal concentration polarization (ICP) within porous substrates can occur less when TFC-EP is used as a membrane. For example, the water flux value of the TFC-EP is 15.7 LMH, whereas the water flux value of the TFC-EC is only 6.6 LMH. Therefore, we strongly believe that the TFC-EP could be a promising candidate with good FO performances.

A Study on the Promotion of Combustible Construction Waste Recycling (가연성 건설폐기물의 자원화 제고를 위한 방안)

  • Park, Ji-Sun;Lee, Sea-Hyun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.1
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    • pp.89-95
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    • 2009
  • The current enforce decree of "The Act on the Promotion of Construction Waste Recycling" divides seventeen kinds of construction wastes by property and configuration. Mixed construction waste, one of them classified by the enforce decree, is composed two more than justified construction wastes except refuse soil and rock. In construction wastes justified by enforce decree of this law, most refuse concrete and asphalt concrete of construction wastes are recycled. As well as refuse metal is separated, sorted from bulk them, and merchandised for value. Finally this is used the secondary manufactured products. Even though combustible construction wastes like refuse wood, plastics, fiber can be recycled RDF(Refuse derived fuel) or RPF(Refuse plastic fuel) because of high caloric value and low heavy metal but most of them are discharged as mixed construction waste and then treated by treated by incineration and landfill. Therefore, to control construction waste flow efficiently, construction wastes are classifies first combustible, incombustible, mixed combustible, incombustible and etc. in this study. The combustible waste is consisted refuse wood, plastics, fiber and etc. and incombustible waste contains refuse concrete, asphalt, and etc. Mixed construction is construction waste that can not separate from mixed waste bulk with different kinds.

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Simultaneous Analysis and Anti-allergic Effect of Mume Fructus (오매(烏梅)의 다성분 동시분석 및 항알러지 효과)

  • Seo, Chang-Seob;Ha, Hyekyung;Lee, Ho Young;Lee, JunKyung;Jung, Dayoung;Lee, Jin-Ah;Shin, Hyeun Kyoo
    • Korean Journal of Pharmacognosy
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    • v.43 no.4
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    • pp.279-285
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    • 2012
  • The Mume Fructus (MF) has been used for relieves cough, arrests arrest chronic diarrhea, treat fluid depletion, and treat ascariasis in Korea. In this study, a high-performance liquid chromatography (HPLC) method was established for simultaneous determination of six main components of MF. Additionally, we were investigated the anti-inflammatory and anti-allergic effects of MF extract on lipopolysaccharide (LPS)-treated RAW264.7 cells and tumor necrosis factor (TNF)-${\alpha}$/interferon (IFN)-${\gamma}$-treated HaCaT cells. The analytical column for separation was used a Gemini $C_{18}$ column maintained at $40^{\circ}C$. The mobile phase consisted of 1.0% (v/v) acetic acid in water (A) and 1.0% (v/v) acetic acid in acetonitrile (B). The flow rate was 1.0 mL/min and the detector was a photodiode array (PDA) set at 280 nm and 320 nm. We evaluated the inhibitory effect of MF extract on the production of inflammatory markers, nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) in LPS-stimulated RAW264.7 cells and thymus- and activation-regulated chemokine (TARC/CCL17) in TNF-${\alpha}$/IFN-${\gamma}$-treated HaCaT cells, respectively. We confirmed the genes expression related with TARC, macrophage-derived chemokine (MDC/CCL22) and regulated on activation, normal T cell expressed and secreted (RANTES/CCL5) in HaCaT keratinocyte cells by MF extract. The contents of the five compounds in MF were 0.22-1.01 mg/g. Also, the MF extract show inhibition of about 78% and 75% on NO and $PGE_2$ production at the concentration 1000 mg/mL in RAW264.7 cells. MF extract suppressed the hTARC level and genes expression such as TARC, MDC, and RANTES on TNF-${\alpha}$/IFN-${\gamma}$-treated HaCaT cells.

The Effect of Slope-based Curve Number Adjustment on Direct Runoff Estimation by L-THIA (경사도에 따른 CN보정에 의한 L-THIA 직접유출 모의 영향 평가)

  • Kim, Jonggun;Lim, Kyoung Jae;Park, Younshik;Heo, Sunggu;Park, Joonho;Ahn, Jaehun;Kim, Ki-sung;Choi, Joongdae
    • Journal of Korean Society on Water Environment
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    • v.23 no.6
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    • pp.897-905
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    • 2007
  • Approximately 70% of Korea is composed of forest areas. Especially 48% of agricultural field is practiced at highland areas over 400 m in elevation in Kangwon province. Over 90% of highland agricultural farming is located at Kangwon province. Runoff characteristics at the mountainous area such as Kangwon province are largely affected by steep slopes, thus runoff estimation considering field slopes needs to be utilized for accurate estimation of direct runoff. Although many methods for runoff estimation are available, the Soil Conservation Service (SCS), now Natural Resource Conservation Service (NRCS), Curve Number (CN)-based method is used in this study. The CN values were obtained from many plot-years dataset obtained from mid-west areas of the United States, where most of the areas have less than 5% in slopes. Thus, the CN method is not suitable for accurate runoff estimation where significant areas are over 5% in slopes. Therefore, the CN values were adjusted based on the average slopes (25.8% at Doam-dam watershed) depending on the 5-day Antecedent Moisture Condition (AMC). In this study, the CN-based Long-Term Hydrologic Impact Assessment (L-THIA) direct runoff estimation model used and the Web-based Hydrograph Analysis Tool (WHAT) was used for direct runoff separation from the stream flow data. The $R^2$ value was 0.65 and the Nash-Sutcliffe coefficient value was 0.60 when no slope adjustment was made in CN method. However, the $R^2$ value was 0.69 and the Nash-Sutcliffe value was 0.69 with slope adjustment. As shown in this study, it is strongly recommended the slope adjustment in the CN direct runoff estimation should be made for accurate direct runoff prediction using the CN-based L-THIA model when applied to steep mountainous areas.