• 한국대기환경학회지
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• 제1권1호
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• pp.99-107
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• 1985

A coated wire ion selective electrode for nitrate (nitrate-CWE_ was constructed using epoxy resin, ion exchanger and plasticizer as a polymer membrane. It's stility, the composition of a polymer membrane, the response characteristics, the selectivity were examined and applied to the environmental analysis. The nitrate-CWE was prepared using a copper wire, wihch was coated with epoxy resin being incorporated with the nitrate ion exchanger and plasticizer. The best composition of the polymer membrane for the nitrate-CWE was obtained by mixing epoxy resin, ion exchanger and plasticizer in the ratio of 2:1:0.4. The potential (56.3$\pm$0.5 mV) of stick form nitrate-CWE in this composition was close to that (59.2 mV) of Nernstian response. The detection limit for nitrate ion were found to the about $6 \times 10^{-5}M$ and the useful pH was 2.5 $\sim$ 10.3. Furthermore, the selectivity of iodide and perchrorate for the nitrage-CWE was also much improved compared with that for a liquid membrane nitrate electrode. The nitrate-CWE was used to determind $NO_x$ in stack gas. The results were in good agreement with those obtained either by electrode method or by the improved NEDA method within a relative error of 4.0%.

• Molecules and Cells
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• 제22권1호
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• pp.21-29
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• 2006

The aim of this study was to determine if hydrogen peroxide ($H_2O_2$) generated by glucose oxidase (GO) induces apoptosis or necrosis of BJAB cells and which radical is the direct mediator of cell death. We found that GO produced $H_2O_2$ continuously in low concentrations, similar to in vivo conditions, and decreased proliferation and cell viability in a dose-dependent manner. The GO-mediated cytotoxicity resulted from apoptosis, and was confirmed by monitoring the cells after H33342/Annexin V/propidium iodide staining. Decreases of mitochondrial membrane potential and intracellular glutathione level were found to be critical events in the $H_2O_2$-mediated apoptosis. Additional experiments revealed that $H_2O_2$ exerted its apoptotic action through the formation of hydroxyl radicals via the Fenton rather than the Haber-Weiss reaction. Moreover, intracellular redox-active iron, but not copper, participated in the $H_2O_2$-mediated apoptosis.

• Bulletin of the Korean Chemical Society
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• 제28권1호
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• pp.68-72
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• 2007

A new PVC membrane potentiometric sensor that is highly selective to Hg2+ ions was prepared, using bis(2-hydroxybenzophenone) butane-2,3-dihydrazone (HBBD) as an excellent hexadendates neutral carrier. The sensor works satisfactorily in the concentration range of 1.0 × 10-6 to 1.0 × 10-1 mol L-1 (detection limit 4 × 10-7 mol L-1) with a Nernstian slope of 29.7 mV per decade. This electrode showed a fast response time (~8 s) and was used for at least 12 weeks without any divergence. The sensor exhibits good Hg2+ selectivity for a broad range of common alkali, alkaline earth, transition and heavy metal ions (lithium, sodium, potassium, magnesium, calcium, copper, nickel, cobalt, zinc, cadmium, lead and lanthanum). The electrode response is pH independent in the range of 1.5-4.0. Furthermore, the developed sensor was successfully used as an indicator electrode in the potentiometric titration of mercury ions with potassium iodide and the direct determination of mercury in some binary and ternary mixtures.

• 대한화학회지
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• 제67권6호
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• pp.429-440
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• 2023

1,1-Dialkyl-2,5-bis(trimethylsilylethynyl)-3,4-diphenylsiloles (R=Et, i-Pr, n-Hex; 3a-c) were prepared and utilized as anode active materials for lithium-ion batteries; 3a was also used as a filler for the solid-state electrolytes (SSE). Siloles 3a-c were prepared by substitution reactions in which the two bromine groups of 1,1-dialkyl-2,5-dibromo-3,4-diphe- nylsiloles, used as precursors, were substituted with trimethylsilylacetylene in the presence of palladium chloride, copper iodide, and triphenylphosphine in diisopropylamine. Among siloles 3a-c, 3a had the best electrochemical properties as an anode material for lithium-ion batteries, including an initial capacity of 758 mAhg^-1 (0.1 A/g), which was reduced to 547 mAhg^-1 and then increased to 1,225 mAhg^-1 at 500 cycles. A 3a-composite polymer electrolyte (3a-CPE) was prepared using silole 3a as an additive at concentrations of 1, 2, 3, and 4 wt.%. The 2 wt.% 3a-CPE composite afforded an excellent ionic conductivity of 1.09 × 10^-3 Scm^-1 at 60℃, indicating that silole 3a has potential applicability as an anode active material for lithium-ion batteries, and can also be used as an additive for the SSE of lithium-ion batteries.

• 공업화학
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• 제8권4호
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• pp.645-652
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• 1997

백금 회전전극을 이용하여 확산지배영역에서의 구리 착화합물의 환원에 대한 전기화학적 특성조사 및 이에 대한 속도인자들을 구하였다. 황산염 용액내에서 Cu(II)의 환원은 2전자, 1단계 반응이며, 염화물 용액내에서의 Cu(II)는 1전자, 2단계 반응으로 환원된다. 환원반응에서의 전달계수는 황산염 용액내에서 Cu(II)가 가장 작으며, 할로겐염 중에서 Cu(I)의 전달계수는 1에 가까운 값을 나타내었다. 염화물 용액안에서 구리이온의 환원에 대한 표준속도상수는 Cu(II)의 환원이 Cu(I)을 출발물질로 할 경우보다 100배 정도 빠른 값을 나타내었다. 그리고 확산계수는 $Cl^-$존재시의 Cu(II), $I^-$, $Br^-$, $Cl^-$존재시의 Cu(I) 및 $SO_4^{-2}$존재시의 Cu(II)의 순으로 증가하였으며, 각 용액 내에서의 구리이온의 반지름 및 확산에 대한 활성화 에너지도 위의 순서와 동일하게 감소하였다. 회전전극상의 구리전착의 경우 전착전위 및 농도에 따라 불균일한 전착표면을 형성하였으며, 이러한 전착표면의 불균일성은 UV/VIS로 분석이 가능하였다.

• Environmental Engineering Research
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• 제17권1호
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• pp.35-39
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• 2012

In this study, multiparametric flow cytometry (FCM) was installed to enumerate the diagnosis of Pseudomonas aeruginosa ATCC 10145 and Escherichia coli K12 (IFO 3301). The nucleic acids (DNA/RNA) were double stained by a LIVE/DEAD bacLight viability kit, involving green SYTO 9 and red propidium iodide (PI), based on the permeability of two chemicals according to the integrity of plasma membrane. As the results showed, the gate for dead bacteria was defined as the range of $0.2{\times}10^0$ to $6.0{\times}10^1$ photo multiplier tube (PMT) 2 fluorescence (X-axis) and $2.0{\times}10^0$ to $2.0{\times}10^2$ PMT 4 fluorescence (Y-axis), and the gate for live bacteria was defined as the range of $6.0{\times}10^0$ to $6.0{\times}10^2$ PMT 2 fluorescence (X-axis) and $2.0{\times}10^0$ to $4.0{\times}10^2$ PMT 4 fluorescence (Y-axis). In the comparison of the number of the tested bacteria detected by FCM (viability assessment) and plate culture (cultivability assessment), the number of bacteria detected by FCM well represented the number of bacteria that was detected by the colony forming unit (CFU) counting method when bacteria were exposed to isopropyl alcohol and silver/copper cations. Consequently, it is concluded that the application of FCM to monitor the functional effect of disinfectants on the physiological status of target bacteria can offer more rapid and reliable data than the plate culture colony counting method.

• 대한방사성의약품학회지
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• 제4권2호
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• pp.45-50
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• 2018

Great efforts are currently devoted to the development of new approaches for the labeling of cells using appropriate radionuclides. While fluoride-18 and copper-64 have been extensively studied as short-term and intermediate-term trafficking agents, iodide was studied less intensely. Here, we report a new cell labeling agent labeled with $^{131}I$, $[^{131}I]$oleyl-4-iodobenzoate ($[^{131}I]$OIB) for long-term cell trafficking. A precursor of $[^{131}I]$OIB was obtained in two steps, with the yield of 35%. The radiochemical yield of $[^{131}I]$OIB was over 50%. While $[^{131}I]$OIB could label different cells, L6 cells showed the highest cell-labeling efficiency. The $[^{131}I]$OIB-labeled L6 cells were imprinted into a rat heart, and then monitored noninvasively for 2 weeks by gamma camera imaging. We conclude that $[^{131}I]$OIB is a good candidate molecule for a long-term cell trafficking agent.

• Current Photovoltaic Research
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• 제11권2호
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• pp.39-43
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• 2023

Carrier-selective contacts (CSCs) solar cells are considerably attractive on highly efficient crystalline silicon heterojunction (SHJ) solar cells due to their advantages of high thermal tolerance and the simple fabrication process. CSCs solar cells require a hole selective contact (HSC) layer that selectively collects only holes. In order to selectively collect holes, it must have a work function characteristic of 5.0 eV or more when contacted with n-type Si. The VO_x, NiO_x, and CuI_x thin films were fabricated and analyzed respectively to confirm their potential usage as a hole-selective contact (HSC) layer. All thin films showed characteristics of band-gap engergy > 3.0 eV, work function > 5.0 eV and minority carrier lifetime > 1.5 ms.

• 한국산림과학회지
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• 제67권1호
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• pp.42-49
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• 1984

Elderberry는 고대인(古代人)에게 약용식물(藥用植物)로 알려졌으며 Europe에서는 옛부터 설사약(지사제(止瀉劑))으로 쓰여 왔다. 꽃은 휘발성 정유(精油)를 함유(含有)하고 있어서 제모(製慕), 향료(香料) 및 로숀 같은 화장품 등에 쓰이는데 주(主)로 꽃을 물로서 증류(蒸溜)해서 사용(使用)하며, 잎은 지방(脂肪)을 green colour로 착색(着色)하는데 사용(使用)되고, 잎과 수피(樹皮)는 곤충(昆虫)이 싫어하는 기피성 물질이 들어 있어서 내충성(耐虫性) 식물(植物)이 된다. 과실(果實)은 향기(香氣)와 천연식용색소(天然食用色素)로서 주요시(主要視)되어 상대적(商業的)으로는 주(主)로 jam, jelly, pies, juice, wine을 만드는데 쓰여진다. 영양가(營養價)는 1941년(年) Andross가 vitamin-c의 함유량(含有量)이 25~30mg/100g 이라고 보고 했으나 그 외(外)의 vitamin이나 각종(各種) mineral 및 영양가(營養價)는 지금까지 보고(報告)된 바 없다. 본(本) 연구(硏究)에서는 각종영양가(各種營養價)와 minerals, vitamins, 그리고 식용천연색소(食用天然色素)의 파장(波長)을 측정(測定)하여 다음과 같은 결과(結果)를 얻었다. 1) 신선(新鮮) Elderberry 과즙(果汁)은 mineral이 11종(種)이 함유(含有)되어 있는 바 Ca : 0.012%, Mg : 0.023%, K : 0.10%, Na : 0.0019%, Fe : 0.0009%, Co : 0.0002%, Zn : 0.0004%, Cu : 0.0001%, P : 0.036%, Mn : 0.0006%, I : $1{\mu}g/g$ 등이 고루 함유(含有)되어 있다. 2) vitamin류(類)는 5종(種)이 함유(含有)되어 있는데, vitamin-$B_1$ : $1{\mu}g/g$, vitamin-$B_2$ : $0.5{\mu}g/g$, vitamin-C : 0.3mg/g, niacin : $14{\mu}g/g$, choline chloride : 0.3 mg/g 으로 되어 있다. 3) 과즙내(果汁內)에는 주요(主要) 영양가(營養價)로서 조단백(粗蛋白) : 1.10%, fat : 026%, carbohydrate : 6.9%, pectin : 0.76%, tannin : 0.89%, ash : 0.80%, water : 90.9% 인데 100g 당 34.3 cal을 보였다. 4) 신선(新鮮)한 과즙(果汁)의 적자색(赤紫色)인 천연색소(天然色素)는 최고파장(最高波長) $523{\sim}530m{\mu}$을 보였다.