• Title/Summary/Keyword: L20 method

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The Reinforcement Method and Stability Analysis of Cut Slopes (절토사면의 안정해석과 보강방법)

  • 지인택;이달원
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.39 no.1
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    • pp.112-121
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    • 1997
  • The aim of this study was to analyze the slope stability relating to the failure of cut slopes and the characteristics of stress-strain relations obtained by limit equilibrium method, finite element method, and stereographic projection method for the reinforced cut slopes. The following conclusions were made : 1.To use stereographic projection method led to little possibility to take the toppling and wedge failure while to use the other methods led to the failure. It was recommended to reduce the slope inclination from 1:1 to 1: 1.5~1 :1.8 and adopt coir mesh method to protect the slope surface. position with the horizontal displacement after final excavation moved to the excavation base. The maximum shear strain values concentrated at the excavation base indicated the possibility to induce the local failure. 3. It was recommended that the slope inclination for blast rock with the slope height larger than l0m was 1: 0.5, 1:1, and 1: 1~1 :1.5 for hard rocks, soft and ordinary rocks, and ripping and soils, respectively. 4. Berm width criteria for blast rock with the slope height larger than l0m were recommended as follow : 2~3m per 20m slope height for hard rocks, 1 ~2m per l0m slope height for soft and ordinary rocks, 1 ~ l.5m per 5m slope height for ripping and soils.

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Separation of liquiritin, glycyrrhizic acid and glabridin from licorice by RP-HPLC (RP-HPLC를 이용한 감초에서 liquiritin, glycyrrhizic acid, glabridin의 분리)

  • Tian, Minglei;Yan, Hongyuan;Row, Kyung Ho
    • Analytical Science and Technology
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    • v.21 no.2
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    • pp.102-108
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    • 2008
  • Reversed-phase high performance liquid chromatography (RP-HPLC) was used for the simultaneous determination of liquiritin (LQ), glycyrrhizic acid (GA) and glabridin from licorice. An optimized run condition was selected with a binary gradient elution of methanol-water which ramped 35/65 to 80/20 (vol. %) in 0.0-8.0 min and a flow rate of 1.0 mL/min. A good linearity was obtained between 0.2 mg/mL and 1.0 mg/mL for LQ and GA, and 0.01 mg/mL-0.2 mg/mL for glabridin with the relative standard deviations less than 0.90% (n=5). The developed method was successfully applied to determination of the three components from licorice samples. The mean recoveries of three components are 80.79% for liquiritin, 89.71% for glycyrrhizic acid and 72.50% for glabridin.

The Development of Cisplatin Analysis Method in Plasma by Flameless Atomic Absorption Spectrometry (FAAS를 이용한 혈중 Cisplatin의 분석법 개발)

  • Paik, Man-Jeong;Lim, Ho-Sub;Jeong, Mi-Jin;Lee, Kyoung-Ok;Shin, Ho-Sang
    • Analytical Science and Technology
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    • v.11 no.4
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    • pp.243-247
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    • 1998
  • Cisplatin is a platinum-containing antitumor agent with nephrotoxic and neurotoxic side effects. An analytical method for measuring cisplatin in plasma by FAAS was developed, which is rapid, simple and need no sample preparation. The linearity test of calibration curve in the range of 20~1000 ng/mL showed good correlation coefficient of r=0.999. The result of accuracy test appeared to be relative standard deviation of < 5.0% at concentration range from 50 to 1000 ng/mL. When $200{\mu}L$ of plasma was used, detection limit was 10 ng/mL. Therefore, it can be applied for the monitoring in plasma for optimal condition of treatment and reduce of toxicity.

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Establishment of Reference Intervals of Osteocalcin according to Age in Women for Health Promotion Center (건강검진이 의뢰된 여성의 연령에 따른 Osteocalcin의 참고범위 설정)

  • Kang, Ji-Soon;Yoo, Byoung-Joo;Oh, Jung-Eun;Kim, Geon-Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.1
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    • pp.104-111
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    • 2009
  • Purpose: Osteocalcin is also known as the bone gamma-carboxyglutamic acid (Gla) protein (BGP), is noncollagenous bone protein synthesized by osteoblasts. Serum concentrations of Osteocalcin have been used as a biochemical marker of bone turnover. The reference intervals of Osteocalcin is categorized by kit corporation according to the age. However, each laboratory should establish its own reference intervals. In this study, the variation in the serum Osteocalcin level were used to find actual standard age-specific Osteocalcin reference intervals. Materials and Methods: We have selected 864 healthy females aged 20~80 years who visited a health promotion center between Aug. 2007 and Sep. 2008. The Osteocalcin IRMA Kit (OSTEO-RIACT, CIS Bio international, Gif-sur-Yvette, France) was used for the quantification. Each results were analyzed with the SPSS 12.0 statistical software. Results: The analyzed reference intervals of Osteocalcin by using Hoffmann method are from 8.8~39.4 ng/mL to 6.3~28.8 ng/mL for the case of the age from 20 to 30, from 7.7~31.9 ng/mL to 5.9~17.4 ng/mL for the case of the age from 31 to 40, and from 8.0~36.0 ng/mL to 5.5~20.1 ng/mL for the case of the age from 41 to 50, and from 8.0~50.5 ng/mL to 6.7~27.0 ng/mL for the case of the age from 51 to 60, and from 12.9~55.9 ng/mL to 7.5~27.5 ng/mL for the case of the age from 61 to 80. Reference intervals of Osteocalcin were not in agreement with those recommended by the manufacturers. Conclusions: Osteocalcin is used as an indication of metabolic bone diseases. So in our study we wanted to provide reference intervals of Osteocalcin that can be useful to a clinical decisions. Also, previous reference intervals should not be re-used and new intervals should be set by continuous analyzing.

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Charaterization of Nisin Production and Resistance of Lactococcus lactis ssp. lactis $ML_8$ (Lactococcus lactis ssp. lactis $ML_8$의 Nisin 생산 및 저항 특성)

  • 김등양;이형주
    • Microbiology and Biotechnology Letters
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    • v.19 no.6
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    • pp.619-623
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    • 1991
  • To investigate nisin production and resistance of Lactococcus lactis ssp. tactis ML (L. lactis $ML_8$, effects of medium, pH of culture broth, and cell growth on the nisin activity, and effect of nisin with or without $Ca^[2+}$ ion on the growth of L. lactzs were analyzed. In the bio-assay of nisin by the agar diffusion method, inhibition-zone diameter of Micrococcus Javus was propotional to the logarithm of nisin concentration ranged 0.5~20 unitlml (12.5~500 ng/mf). Nisin activity of the pasteurized culture filtrates of L. lactis MLs was high at pH 2!3 but was inactivated completely at pH over 6.0. Nisin production of the L. lactis $ML_8$ cultured on LTB broth increased at late logarithmic phase and reached 10.5 unitlml after 16 hr. The cell growth of L. lactis LM 0230, a plasmid free and nisin sensitive strain, was inhibited on agar medium containing 7 unitlrnl of nisin, while L. lactis $ML_8$ showed high survival ability at 20 unitld of nisin. When 40 mM $Ca^[2+}$ ion was added to Elliker broth with 8 unitlml of nisin, the growth pattern of L. lactis $ML_8$ was similiar to that on control medium which did not contain nisin and $Ca^[2+}$ ion, and this suggested that $Ca^[2+}$ increased the nisin resistance of the L. lactis.

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Somatic Embryogenesis and Plant Regeneration in Immature Flower Bud Cultures of Carnation (카네이션의 미숙화뢰 배양을 통한 체세포배 발생 및 식물체 재분화)

  • 안병준
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.6
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    • pp.369-374
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    • 1997
  • Immature flower buds of 'Desio' carnation were cultured on MS agar medium supplemented with 1 ㎎/L 2,L-D. Embryogenic calli were formed from 5-10% of the buds less than 20 ㎜ in length, but only non-embryogenic calli were produced from explants of shoot apex leaf, internode, and flowere buds larger than 20 ㎜. The same method was applied to 16 cultivars of cut Sower carnation and embryogenic calli were obtained in 7 cultivars. Several embryogenic callus lines were selected and maintained through subcultures over 120 weeks without loss of embryogenic competence. The embryogenic cultures were also proliferated rapidly in liquid agitation cultures using MS medium supplemented with 1mg/L 2,4-D. Numerous embryos were formed on the periphery of the cell aggregates upon transfer to auxin-free MS agar medium. Plantlets were transplanted in potting soil and grown to bloom in six months.

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Chemical Equilibria of Lanthanides{Ln(Ⅲ)=Pr, Sm, Gd, Dy}-Macrocyclic Complexes with Auxiliary Ligands in $CH_3OH$(PartⅡ):Study of the Coordination of Oxygen-Containing Bases. ($CH_3OH$ 용매에서 란탄족 원소{Ln(Ⅲ)=Pr, Sm, Gd, Dy}-거대고리 착물과 보조 리간드 간의 화학평형 (제2보): 주게원자가 산소인 염기를 중심으로 고찰.)

  • Byun, Jong Chul;Park, Yu Chul;Han, Chung Hun
    • Journal of the Korean Chemical Society
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    • v.43 no.6
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    • pp.628-635
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    • 1999
  • Direct preparative method of 2,6-diformyl-p-cresol and 2-hydroxy-3-hydroxy-5-methylbenzaldehyde from 2,6-bis(hydroxymethyl)-4-methylphenol using activated $Mn(IV)O_2$ was described. Hexadentate compartmental Iigands, $H_4L[A]\;and\; H_4L[B]$ were prepared by condensation reactions of 2-hydroxy-3-hydroxy methyl-5-methylbenzaldehyde with ethylenediamine and 1,3-diaminopropane respectively. By the reaction of macrocycle($H_4[20]DOTA$) with Ln(III) nitrate {Ln(III)=Pr, Sm, Cd, Dy }, discrete mononuclear Ln(III) complexes of the type $[Ln(H_2[20]DOTA)(ClO_4)(H_2O)]\;{\cdot}\;3H_2O$ were synthesized in the solid state. $[Ln([20]DOTA)(NO_3)(H_2O)](NO_3)_2\;{\cdot}\;xH_2O$ was placed in methanol for 2 days, and $[Ln([20]DOTA)(NO_3)(CH_3OH)]^{2+}$ was formed. The equilibrium constants(K) for the substitution of coordinated $CH_3OH$ in the Ln-[20]DOTA complexes by various auxiliary ligand, $L_a$(=salicylic acid, p-chlorobenzoic acid, benzoic acid, acetic acid, 4-bromophenol) were determined spectroscopically at 25$^{\circ}C$ and 0.1M $NaClO_4$. The K values calculated were in the order of salicylic acid > p-chlorobenzoic acid > benzoic acid > acetic acid > 4-bromophenol, while pKa of auxiliary ligands was in the opposite trend.

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Sensitive Determination of Felodipine in Human Plasma by LC-MS/MS

  • Kim, Ho-Hyun;Roh, Hyeon-Jin;Lee, He-Joo;Han, Sang-Beom
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.283.2-283.2
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    • 2003
  • This study established a highly sensitive novel quantification method for detecting felodipine in human plasma using LC-MS/MS. The mobile phase used after degassing was composed of 1 mM ammonium acetate and acetonitrile (20:80, pH 6.0), with flow rate of 200 uL/min. One mL plasma were pipetted into glass tubes and spiked with 0.1 mL of internal standard solution. (omitted)

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Determination of Glimepiride in Human Plasma by LC-MS/MS

  • Kim, Ho-Hyun;Roh, Hyeong-Jin;Lee, Hee-Joo;Han, Sang-Beom
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.282.1-282.1
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    • 2003
  • This study established a sensitive novel Quantification method for detecting glimepiride in human plasma using LC-MS/MS for pharmacokinetic studies. The mobile phase used after degassing was composed of 10 mM ammonium acetate and acetonitrile (20:80, pH 3.0), with flow rate of 200uL/min. One mL plasma were pipetted into glass tubes and spiked with 0.1 mL of internal standard solution. (omitted)

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Antioxidant Activity of Partially Purified Extracts Isolated from Bacillus polyfermenticus SCD Culture

  • Kim, Tae-Hoon;Lee, Na-Kyoung;Chang, Kyung-Hoon;Park, Eun-Ju;Choi, Shin-Yang;Paik, Hyun-Dong
    • Food Science and Biotechnology
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    • v.15 no.3
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    • pp.482-484
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    • 2006
  • The antioxidant activity of Bacillus polyfermenticus SCD was studied by partially purified culture extracts using various methods: ammonium sulfate precipitation, adsorption to Diaion HP-20 columns using polar solvents, and extraction using non-polar solvents. The 1,1-diphenyl-2-picyrylhydrazyl (DPPH) radical scavenging activity of these partially purified fractions was then investigated. The precipitate isolated using 75%-saturated ammonium sulfate was shown to contain about 77.2% DPPH radical scavenging activity. Using the Diaion HP-20 resin adsorption method, the fraction obtained using 60% ethanol and 60% methanol possessed 76.7 and 89.5% DPPH radical scavenging activity, respectively. Fractions obtained by extracting with the non-polar solvents 80 mg/mL chloroform, 80 mg/mL n-hexane, 80 mg/mL ethyl acetate, and 80 mg/mL butanol contained 68.4, 75.0, 70.7, and 87.5% DPPH radical scavenging activity, respectively. Further study is needed to characterize the antioxidant substance(s) released by B. polyfermenticus SCD cultures.