• Title/Summary/Keyword: IOTA

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Differential Pulse Voltammetric Determination of Co(II) Ion with a Chemically Modified Carbon Paste Electrode Containing ${\iota}$ -Sparteine (${\iota}$ -Sparteine으로 변성된 Carbon Paste 전극을 사용한 Co(II) 이온의 펄스 차이 전압-전류법 정량)

  • Eu-Duck Jeong;Mi-Sook Won;Deog-Su Park;Yoon-Bo Shim;Sung-Nak Choi
    • Journal of the Korean Chemical Society
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    • v.37 no.10
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    • pp.881-887
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    • 1993
  • A cobalt(II) ion-selective carbon-paste electrode (CPE) was constructed with ${\iota}$-sparteine. Cobalt(II) ion in aqueous solution was chemically deposited through the complexation with ${\iota}$-sparteine onto the CPE. The surface of CPEs were characterized by cyclic voltammetry and differential pulse voltammetry in an acetate buffer solution, separately. Exposure of the CPEs to an acid solution could regenerate surface to reuse it for the deposition. In more than 5 deposition / measurement / regeneration cycles, the response was reproducible and linear up to $5.0{\times}10^{-6}$M with linear sweep voltammetry. The peaks at 0.17V / 0.27V were correspond to the redox of Co(II)-SP complex deposited on CPE. The anodic peak of which appeared after scan over the cathodic peak of 0.17 V to more negative scan. In case of using the differencial pulse voltammetry (DPV), we have obtained the linear response $2.0{\times}10^{-7}$M with relative standard deviation ${\pm}5.6%$. The detection limit was $1.0{times}10^{-7}$M for 20 minutes of the deposition. We have also investigated the interference effect of various metal ions, which are expected to form the complex with the ligand on the electrode.

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Mechanical properties of carrageenan-based biopolymer films (카라기난 생고분자 필름의 기계적 물성에 관한 연구)

  • Park, Hyun-Jin;Rhim, Jong-Whan;Jung, Soon-Teck;Kang, Seong-Gook;Hwang, Keum-Taek;Park, Yang-Kyun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.1 no.1
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    • pp.38-50
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    • 1995
  • Tensile strength (TS) of ${\kappa}-carrageenan$ films without salt was 22-32 MPa and was the highest among ${\kappa},\;{\lambda}\;and\;{\iota}-carrageenan$ films. ${\kappa}-carrageenan$ films had high mechanical barrier properties as they are compared with TS of polyethylene films which are 13-28 MPa. TS of ${\iota}-carrageenan$ films without salt was 5-9 MPa and was the lowest among the films. Mechanical properties (TS and elongation) were affected by the concentration of plasticizers. Especially, elongation of ${\kappa}-carrageenan\;and\;{\iota}-carrageenan$ drastically increased as the concentration of plasticizer increased. Mechanical properties (TS and elongation) were greatly affected by various concentration and kind of salts. TS of Film-A (0.375 g plasticizer/g carrageenan) of ${\kappa}-carrageenan$ films which contains 0.1% (w/w) potassium chloride increased to 45 MPa which was the highest among the TS of biopolymer films which have been developed.

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Oxygen Pulse in Load Carrying (물체 운반작업에 의한 산소맥의 변화)

  • Lee, Byung-Kuk;Bae, Tal-Sik;Jin, Hang-Ki;Chung, Kyou-Chull
    • Journal of Preventive Medicine and Public Health
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    • v.5 no.1
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    • pp.105-110
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    • 1972
  • On 6 healthy adult males aged 20-30 years, oxygen pulse was observed during carrying sand bags weighing 10, 20 and 30 kg on a level treadmill running with speeds of 3, 4 and 5 km/hr. The results obtained were as follows. 1. Oxygen pulse during load carrying on a level treadmill was proportionately increased with an increase of work load, average oxygen uptake per minute. Regression equation of oxygen pulse (y: $m\iota$/beat) on the average oxygen uptake (x:$\iota$/min) required for each grade of work was expressed as y=3.34x+5.99, $s_{y.x}=0.858$). 2. Oxygen pulse reached the highest value 2-5 minutes after the start of load carrying, and thereafter it decreased gradually to some extend as the load carrying was continued. Rate of decrease in the oxygen pulse was greater in lighter works. 3. In lighter works requiring less than $2.0\iota/min$ of oxygen uptake, no difference in oxygen pulse could be seen between methods of carrying even when the same amount of load was carried. In heavier works requiring more than $2.0\iota/min$ of oxygen uptake, oxygen pulse was larger in case of carrying a load by embrace, in both hands and on head than on back or on shoulder.

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On the historical investigation of Bernoulli and Euler numbers associated with Riemann zeta functions (수학사적 관점에서 오일러 및 베르누이 수와 리만 제타함수에 관한 탐구)

  • Kim, Tae-Kyun;Jang, Lee-Chae
    • Journal for History of Mathematics
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    • v.20 no.4
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    • pp.71-84
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    • 2007
  • J. Bernoulli first discovered the method which one can produce those formulae for the sum $S_n(k)=\sum_{{\iota}=1}^n\;{\iota}^k$ for any natural numbers k. After then, there has been increasing interest in Bernoulli and Euler numbers associated with Riemann zeta functions. Recently, Kim have been studied extended q-Bernoulli numbers and q-Euler numbers associated with p-adic q-integral on $\mathbb{Z}_p$, and sums of powers of consecutive q-integers, etc. In this paper, we investigate for the historical background and evolution process of the sums of powers of consecutive q-integers and discuss for Euler zeta functions subjects which are studying related to these areas in the recent.

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Distribution of Suspended Clay Minerals around the Kori Waters (고리 부근 현탁물중 점토광물의 분포에 관한 연구)

  • Kim Dae-Choul;Kim Jung-Moo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.2
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    • pp.145-154
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    • 1990
  • Amounts of total suspended matter(TSM) around the Kori waters have been monitored for two years to understand the dispersal pattern of fine-grained sediment. Average concentration of the TSM is $3\~4\;mg/\iota$ in the surface and $3.5\~5\;mg/\iota$ in the near-bottom water. Semi-quantitative analysis for the four major clay minerals in TSM is also performed. The average relative abundance of each clay mineral such as illite, kaolinite, chlorite, and smectite is $65\%,\;17\%,\;17\%$, and $1\%$, respectively. It seems that the majority of recent fine-grained sediment deposited around the Kori area is derived from the Nakdong River. The texture of surface sediment is also dominated by fine-grained fraction leading up to $90\%$ of silt and clay content. The grain size decreases seaward progressively.

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Mercury Pollution in the Onsan Coastal Area (온산연안해역의 수은오염에 관한 연구)

  • PARK Chung-Kil;PYEN Jong-Ryool;YOU Sun-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.22 no.5
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    • pp.233-240
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    • 1989
  • The concentration of mecury was measured in the seawater, sediment, Mytilus edulis and suspended solid in the coastal area of Onsan. Samples were collected at spring and neap tide in the period from October 9 to November 2, 1984. The range and mean of mecury concentration in the seawater are $0.08\~0.73{\mu}g/\iota\;and\;0.19{\mu}g/\iota$. The range and mean of mecury concentration in the suspended solid was $0.70\~17.0{\mu}g/g$ TSS and $4.6{\mu}g/g$ TSS respectively. The average concentration of mecury in Mytilus edulis was 0.10mg/kg which was higher than that of the reference area, Chung Mu. The mean value of concentration factor of mercury in wet base is 500 in Mytilus edulis. The average concentration of mecury in sediment was 0.15mg/kg.

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Formation of DNA-Protein Crosslink at Oxidized Abasic Site Mediated by Human DNA Polymerase Iota and Mitochondrial DNA Polymerase Gamma

  • Son, Mi-Young;Jun, Hyun-Ik;Goo, Sun-Young;Sung, Jung-Suk
    • Biomedical Science Letters
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    • v.15 no.1
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    • pp.1-8
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    • 2009
  • Human genomic DNA is continuously attacked by oxygen radicals originated from cellular metabolic processes and numerous environmental carcinogens. 2-deoxyribonolactone (dL) is a major type of oxidized abasic (AP) lesion implicated in DNA strand scission, mutagenesis, and formation of covalent DNA-protein crosslink (DPC) with DNA polymerase (Pol) ${\beta}$. We show here that human DNA polymerase (Pol)${\iota}$ and mitochondrial $Pol{\gamma}$ give rise to stable DNA-protein crosslink (DPC) formation that is specifically mediated by dL lesion. $Pol{\gamma}$ mediates DPC formation at the incised dL residue by its 5'-deoxyribose-5-phosphate (dRP) lyase activity, while $Pol{\gamma}$ cross links with dL thorough its intrinsic dRP lyase and AP lyase activities. Reactivity in forming dL-mediated DPC was significantly higher with $Pol{\gamma}$ than with $Pol{\iota}$. DPC formation by $Pol{\gamma}$, however, can be reduced by an accessory factor of $Pol{\gamma}$ holoenzyme that may attenuate deleterious effects of crosslink adducts on mitochondrial DNA. Comparative kinetic analysis of DPC formation showed that the rate of DPC formation with either $Pol{\iota}$ or $Pol{\gamma}$ was lower than that with $Pol{\beta}$. These results revealed that the activity of catalytic lyase in DNA polymerases determine the efficiency of DPC formation with dL damages. Irreversible crosslink formation of such DNA polymerases by dL lesions may result in a prolonged strand scission and a suicide of DNA repair proteins, both of which could pose a threat to the genetic and structural integrity of DNA.

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Effect of Ozone and Anion Treatment for Livestock Drinking Water (오존$\cdot$음이온을 이용한 가축음용수 처리효과)

  • Choi H. C.;Lee D. S.;Kang H. S.;Kwon D. J.;Yoo Y. H.;Yeon K. Y.;Song J. I.;Yang C. B.;Kim Y. K.
    • Journal of Animal Environmental Science
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    • v.10 no.2
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    • pp.87-92
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    • 2004
  • This research was carried out to investigate the effects of ozone and anion treatments in improving the quality of the drinking water far livestock. The drinking water was treated with an ozone concentration of 0.658 $\~$0.722 g/h and with anion of 3.27 $\~$ 6.17$\times$1,000,000 pieces/sec. With the ozone and anion treatments, the pH was significantly increased from a range of pH 6.38 $\~$ 7.14 to a range of pH 7.5 $\~$ 7.8(P<0.05). Also, with the ozone and anion treatments, the dissolved oxygen (DO) concentration in the drinking water was increased from a range of 2.0 $\~$ 3.5 mg/$\iota$ to 5.5 $\~$ 6.1 mg/$\iota$(P<0.05): the DO decreased in the control. The dissolved ozone was not increased in the beginning of the experiment, but was increased by 0.48$\~$0.56 mg/L after 48 h of the ozone and anion treatment. The colony numbers of Staphylococcus aureus, Salmonella enteritis, and Escherichia coli disappeared after one hour of ozone and anion treatment.

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