• Journal of Plant Biotechnology
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• 제33권4호
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• pp.249-255
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• 2006

Effects of ethylene inhibitors like silver nitrate $(AgNO_3)$, cobalt chloride $(CoCl_2)$ and Salicylic acid (SA) on multiple shoot induction and their impact on ethylene production using embryonal cotyledon cultures of Cucumis sativus L. were examined. The optimum concentration of $AgNO_3\;(40{\mu}M),\;CoCl_2\;(20{\mu}M)\;and\;SA\;(20{\mu}M)$, separately, induced maximum number of shoots on Murashige and Skoog's (MS) medium supplemented optimally with $4.44{\mu}M$ BA and $0.25{\mu}M$ NAA. Among the three ethylene inhibitors tested, $AgNO_3$ produced maximum number of shoots when compared to $CoCl_2$ and SA Ethylene production was monitored in all the treatments with $AgNO_3/CoCl_2/SA$ and it was observed that the treatment with $AgNO_3$ alone showed increase in ethylene production when compared to $CoCl_2$ and SA Even though ethylene concentration was the highest in $AgNO_3$ treated explants, maximum number of shoots was obtained.

• 한국약용작물학회지
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• 제5권2호
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• pp.102-107
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• 1997

명일엽(明日葉)의 부위별 캘러스 유도율을 조사하였고, 배발성(胚發生) 캘러스로부터 식물체 재분화율을 높이고자 에틸렌 작용억제제(作用抑制劑)를 처리한 후, 신초(新梢)의 발생정도 및 소식물체의 길이와 무게를 조사하였던 바 그 결과는 다음과 같다. 1. 2, 4-D의 농도를 달리한 MS배지에 명일엽(明日葉)의 소엽(小葉), 소엽병(小葉柄) 및 엽병(葉柄) 절편(切片)을 배양하였을 때 캘러스 유도는 소엽(小葉)에서 잘 되었으며 2, 4-D의 농도는 2.0 ppm에서 제일 좋았다. 2. 배발성(胚發生) 캘러스로부터 신초의 발생정도와 재분화(再分化)된 소식물체(小植物體)의 신초(新梢) 신장(伸長)에는 $AgNO_3$는 2 ppm, $CoCl_2{\cdot}6H_2O$는 10ppm 첨가가 제일 효과적이었으며, $AgNO_3$나 $CoCl_2{\cdot}6H_2O$를 2, 4-D 1 ppm과 혼용처리하면 신초의 발생정도와 신장은 억제되었다. 3. 재분화된 소식물체(小植物體)의 뿌리 신장(伸長)에는 $AgNO_3$는 1 ppm, $CoCl_2{\cdot}6H_2O$는 5 ppm 첨가가 제일 효과적이었는데, $AgNO_3$나 $CoCl_2{\cdot}6H_2O$를 2, 4-D 1 ppm과 혼용처리 하면 뿌리의 발생은 없었다. 4. 재분화된 소식물체(小植物體)의 생체중은 $AgNO_3$나 $CoCl_2{\cdot}6H_2O$를 단용처리한 경우 각각 2 rpm에서, 2, 4-D 1 ppmr과 혼용처리한 경우 $AgNO_3$는 1 ppm 과 $CoCl_2{\cdot}6H_2O$는 2 ppm에서 제일 무거웠다.

• 식물조직배양학회지
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• 제26권4호
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• pp.259-264
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• 1999

애기장대 (Arabidopsis thaliana)생태종 'Columbia'의 잎절편 배양시 부정근, 모용 및 캘러스 형성에 미치는 에틸렌의 역할을 알아보고자 ACC, ethephon, CoCl$_2$및 AgNO$_3$의 영향을 조사하였다. 애기장대 잎 절편을 부정근 (0.1 mg/L NAA), 모용 (2.0mg/L NAA) 및 캘러스 (10.0mg/L - NAA)를 형성하는 MS 배지 각각에 ACC와 ethephon을 1-100mg/L 처리한 결과 부정근 형성구에서는 부정근이 감소 한 반면 모용이 유기되었고 모용 형성구에서는 모용이 감소한 반면 캘러스가 유기되었다. 또한 CoCl$_2$와 AgNO$_3$를 1-100mg/L 처리한 결과 부정근 형성구에서는 모용 형성 없이 부정근이 증가하였으며, 모용 형성구에서는 모용은 감소한 반면 부정근이 유기되었다. 그리고 캘러스 형성구에서는 ACC, ethephon, CoCl$_2$및 AgNO$_3$처리구 모두에서 캘러스 형성이 억제되면서 모용이 형성되었다.

• 한국분말재료학회지
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• 제12권1호
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• pp.56-63
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• 2005

Ag powder was prepared from $AgNO_3$ by wet chemical reduction method using various reduction agent system involving $AgNO_3$, $AgNO_2$(AgCl) and Ag complex ion aqueous solution. The pure Ag powder could be prepared regardless of reaction system but the particle shape and distribution were affected very much according to the kind of reduction agents and reaction systems. The optimum reaction system for the preparation of the silver powder having the uniform particle shape and size distribution was Ag complex ion aqueous solution-reduction agent system and in particular, $H_2O_2$ and $C_6H_8O_6$as a reduction agent leaded the more uniform particle shape and size distribution.

• 한국약용작물학회지
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• 제14권6호
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• pp.367-370
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• 2006

The study was carried out to establish an improved protocol for shoot organogenesis and plant regeneration from leaf explant cultures of Scrophularia buergeriana M. with the treatment of ethylene inhibitors [silver nitrate (AgNO$_3$), aminoethox-yvinylglycine (AVG), Cobalt chloride (CoCl$_2$)]. The regenerated shoots obtained from leaf explant cultures on MS medium containing 2 mg/l BAP, The additions of AgNO$_3$. AVG and CoC1$_2$ substantially improved the shoot regeneration frequency, at the optimal concentration of 7 mg/L, 7 mg/L, and 3 mg/L respectively, The regenerated shoots could be easily rooted with 0.1 mg/L IBA treatment. The noted plants were hardened and transferred to vermiculite with a 85% survival rate where they grew normally.

• 자원리싸이클링
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• 제26권1호
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• pp.30-36
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• 2017

양극흙에 함유된 금과 은을 회수하기 위해 무기산(염산, 질산, 황산)과 thiourea 및 thiosulfate에 의한 침출실험을 수행했다. 산화제를 첨가하지 않은 조건에서 금은 무기산용액에 전혀 용해되지 않았다. 3종류의 무기산의 농도가 동일한 조건에서 황산용액에서 은의 침출율이 가장 높았으며, 염산의 농도가 증가함에 따라 $AgCl_2{^-}$의 형성에 따라 은의 침출율이 증가하였다. 한편 주석은 질산용액에 전혀 용해되지 않았으나, 구리, 니켈과 아연은 본 실험조건에서 모두 용해되었다. 황산과 thiourea의 혼합용액에서 금과 은은 모두 용해되었다. Thiosulfate용액에 은의 일부가 용해되었으나, 금은 전혀 용해되지 않았다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2017년도 춘계학술대회 논문집
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• pp.96.2-96.2
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• 2017

This research was conducted to investigate the electrochemical properties of the thin air-formed oxide film-covered AZ31 Mg alloy. In this work, native air-formed oxide films on AZ31 Mg alloy samples were prepared by knife-abrading method and the changes in the electrochemical properties of the air-formed oxide film were investigated in seven different electrolytes containing the following anions $Cl^-$, $F^-$, $SO{_4}^{2-}$, $NO_3{^-}$, $CH_3COO^-$, $CO{_3}^{2-}$ and $PO{_4}^{3-}$. It was observed from open circuit potential (OCP) transients that the potential initially decreased before gradually increasing again in the solutions containing only $CO{_3}^{2-}$ or $PO{_4}^{3-}$ ions, indicating the dissolution or transformation of the native air-formed oxide film into new more protective surface films. The Nyquist plots obtained from electrochemical impedance spectroscopy (EIS) showed that there was growth of new surface films with immersion time on the air-formed oxide film-covered specimens in all the electrolytes; the least resistive surface films were formed in fluoride and sulphate baths whereas the most protective film was formed in phosphate bath. The potentiodynamic polarization curves illustrated that passive behaviour of AZ31 Mg alloy under anodic polarization appears only in $CO{_3}^{2-}$ or $PO{_4}^{3-}$ ions containing solutions and at more than $-0.4V_{Ag/AgCl}$ in $F^-$ ion containing solution.

• 한국표면공학회지
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• 제50권3호
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• pp.147-154
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• 2017

This research was conducted to investigate the electrochemical properties of the thin air-formed oxide film-covered AZ31 Mg alloy. Native air-formed oxide films on AZ31 Mg alloy samples were prepared by knife-abrading method and the changes in the electrochemical properties of the air-formed oxide film were investigated in seven different electrolytes containing the following anions $Cl^-$, $F^-$, $SO{_4}^{2-}$, $NO_3{^-}$, $CH_3COO^-$, $CO{_3}^{2-}$, and $PO{_4}^{3-}$. It was observed from open circuit potential (OCP) transients that the potential initially decreased before gradually increasing again in the solutions containing only $CO{_3}^{2-}$ or $PO{_4}^{3-}$ ions, indicating the dissolution or transformation of the native air-formed oxide film into new more protective surface films. The Nyquist plots obtained from electrochemical impedance spectroscopy (EIS) showed that there was growth of new surface films with immersion time on the air-formed oxide film-covered specimens in all the electrolyte. The least resistive surface films were formed in fluoride and sulphate baths whereas the most protective film was formed in phosphate bath. The potentiodynamic polarization curves illustrated that passive behaviour of AZ31 Mg alloy under anodic polarization appears only in $CO{_3}^{2-}$, or $PO{_4}^{3-}$ ions containing solutions and at more than $-0.4V_{Ag/AgCl}$ in $F^-$ ion containing solution.

• Preventive Nutrition and Food Science
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• 제15권3호
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• pp.189-195
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• 2010

Water extracts from 20 medicinal plants, traditionally used for postmenopausal symptoms in Korea, were examined for their vasorelaxant activity in isolated rat thoracic aorta rings precontracted with norepinephrine (NE). Among the 20 medicinal plants, Cornus officinalis (CoEx, 0.3 mg/mL), Schisandra chinensis (ScEx, 0.3 mg/mL), Erythrina variegate (EvEx, 0.3 mg/mL), and Epimedium koreanum (EkEx, 0.3 mg/mL) showed rapid relaxation of endothelium-intact aorta ($69\pm4%$, $40\pm3%$, $25\pm2%$, and $23\pm3%$ of active tone induced by NE, respectively). In contrast, the extracts of Erythrina variegata (EvEx), Angelica gigas (AgEx), Pueraria thunbergiana (PtEx), and EkEx lead to gradual (i.e., long-term) relaxation to baseline in endothelium-intact vessels. The time to complete relaxation was 20～40 min. These 6 plant extracts were selected for the investigation of possible underlying mechanisms. The CoEx-, ScEx-, or EkEx-induced rapid relaxations were virtually abolished by endothelium denudation, and were significantly inhibited by pretreatment with nitric oxide (NO) synthase inhibitor $N^G$-nitro-L-arginine (L-NNA, 10 ${\mu}M$), indicating that increased formation of NO might contribute to the endothelium-mediated relaxation. In long-term responses, the endothelium denudation did not affect PtEx-induced relaxation, whereas it delayed responses by EvEx and AgEx, and significantly inhibited the effect of EkEx. Among EvEx, AgEx, and PtEx, EvEx attenuated the $CaCl_2$-induced vasoconstriction in high-potassium depolarized medium, implying that EvEx is involved in inhibition of the extracellular calcium influx to smooth muscle through voltage dependent calcium channels. These results provide the scientific rationale for the interrelationships between the use of 20 medicinal plants and their effects on cardiovascular health in estrogen deficient conditions.

• Bulletin of the Korean Chemical Society
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• 제31권11호
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• pp.3077-3083
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• 2010

The electrochemical detection of As(III) was investigated on a platinum-iron(III) nanoparticles modified multiwalled carbon nanotube on glassy carbon electrode(nanoPt-Fe(III)/MWCNT/GCE) in 0.1 M $H_2SO_4$. The nanoPt-Fe(III)/MWCNT/GCE was prepared via continuous potential cycling in the range from -0.8 to 0.7 V (vs. Ag/AgCl), in 0.1 M KCl solution containing 0.9 mM $K_2PtCl_6$ and 0.6 mM $FeCl_3$. The Pt nanoparticles and iron oxide were co-electrodeposited into the MWCNT-Nafion composite film on GCE. The resulting electrode was examined by cyclic voltammetry (CV), scanning electron microscopy (SEM), and anodic stripping voltammetry (ASV). For the detection of As(III), the nanoPt-Fe(III)/MWCNT/GCE showed low detection limit of 10 nM (0.75 ppb) and high sensitivity of $4.76\;{\mu}A{\mu}M^{-1}$, while the World Health Organization's guideline value of arsenic for drinking water is 10 ppb. It is worth to note that the electrode presents no interference from copper ion, which is the most serious interfering species in arsenic detection.