• Korean Journal of Microbiology
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• v.24 no.2
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• pp.133-140
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• 1986

Extracts of CO-autotrophically grown cells of Acinetobacter sp. 1 were shown to use thionin, methylene blue, or 2,6-dichlorophenol-indophenol, but not NAD, NADP, FAD, or FMN, as electron acceptors for the oxidation of CO under strictly anaerobic conditions. The CO dehydrogenase (CO-DH) in the thes bacterium was found to be an inducible enzyme. The enzyme activity was determined by an assay based on the CO-dependent reduction of thionin. Maximal reaction rates were found at pH 7.5 and $60^{\circ}C$, and the Arrhenius plot revealed an activation energy of 6.1 kcal/mol(25.5kJ/mol). THe $K_m$ m/ for CO was $154{\mu}M$. Known metalchelating agents tested had no effects on the CO-DH activity. No divalent cations tested affect the enzyme activity significantly escept $Cu^{2+}$ which suppressed the activity completely. The enzyme was inhibited by glucose and succinate. The same extracts catalyzed oxidation of hydrogen gas and formate with thionin as electron acceptor. The CO-DH of Acinetobacter sp. 1 was to have no immunological relationship with that of Pseudomonas carboxydohydrogena.

• Journal of Forest and Environmental Science
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• v.15 no.1
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• pp.71-76
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• 1999

This study compared soil characteristics and carbon storage between urban and natural lands in Chunchon. Soil pH was lower in natural lands (5.0) than in urban lands (6.6), and therefore exchangeable cation was a little lower in natural lands. Organic matter and cation exchange capacity were respectively, 1.4 and 1.7 times higher in natural lands than in urban lands, while available $P_2O_5$ was about 3.2 times higher in urban lands. Organic carbon storage in soils averaged $24.8{\pm}1.6$ (standard error) t/ha in urban lands and $31.6{\pm}1.6t/ha$ in natural lands, 1.3 times greater than in urban lands. Annual carbon accumulation in soils of natural lands was 1.3 t/ha/yr (litterfall minus decomposition). The carbon storage in Chunchon' s soils equaled about 31% of annual carbon emission (245,590 t/yr).

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.512-516
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• 1998

탄소재료는 높은 전기전도도 및 기계적 강도, 화학적 안정성, 큰 비표면적(1000~3000$m^2$/g) 등의 특성 때문에 연료전지, 리튬이온 이차전지, 전기 이중층 캐패시터(electric double layer capacitor, EDLC).의 전극 활물질로 주목받고 있다[1]. 탄소섬유는 보통 특성과 전구체 핏치에 따라서 두 가지 종류로 분류된다[2]. 하나는 메조페이스 핏치로부터 제조된 고성능 탄소섬유(HPCF)이다. (중략)

• Journal of the Korean Electrochemical Society
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• v.8 no.2
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• pp.77-81
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• 2005

Porous-composite electrodes have been developed using silica gel, which reduce carbon aerogel usage with high cost. Silica gel powder was added to the carbon aerogel to simplify the manufacturing procedure and to increase the wet-ability, the mechanical strength and the CDI efficiency. Porous composite electrodes composed of carbon aerogel and silica gel powder were prepared by paste rolling method. Carbon aerosol composite electrodes with $10\times10cm^2$ are placed face to face between spacers, and assembled the four-stage series cells for CDI process. Each stage is composed of 45 cells. Four-stage series cells (flow through cells) for CDI process are put in continuous-system reactor containing 1,000ml-NaCl solution bath of 1,000 ppm. The four-stage series cells with carbon aerogel electrodes are charged at 1.2V and are discharged at 0.001V, and then read the current. Conclusively, removal efficiencies of ions using the four-stage series cells composed of carbon aerogel composite electrodes show good removal efficiency of $99\%$ respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.240-240
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• 2012

Linear ion source (LIS)를 사용하여 Si wafer 위에 Si 이온이 첨가된 DLC 박막을 증착하였다. 참가된 Si 이온의 양에 따라 DLC 박막에 미치는 영향을 분석하기 위하여 마찰 계수 및 경도를 비교하였고, Micro raman spectroscopy, Field Emission-Scanning Electron Microscope(FM-SEM) and X-ray Photoelectron Spectroscopy (XPS)를 통하여 표면 상태를 분석하였다. 천체 주입된 가스량의 약 2%까지 Si 이온 주입이 늘어날수록 DLC 박막의 마찰계수는 낮아졌고, 경도는 Si 이온이 주입되지 않았을 경우와 비슷한 값(약 20~23GPa)을 가졌다. 2% 이상의 주입량에서는 마찰계수는 주입량이 늘어날수록 높아졌으며 경도는 떨어지는 경향을 보였다. 이는 Si 이온이 2% 이하로 첨가되었을 경우, DLC 박막의 생성시 탄소 이온들의 결합 Stress를 줄여 마찰계수가 줄어든다고 볼 수 있으며, 그 양이 2% 이상이 되면 오히려 불순물로 작용하여 DLC 박막의 Stress는 급격히 증가하고 마찰계수도 높아짐을 알 수 있다.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.12
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• pp.873-878
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• 2014

The applicability of carbon nanotube (CNT) to slow sand filtration for the removal of bacteria was studied using scanning electron microscope and column experiments. The morphology of CNT were investigated using scanning electron microscope and the CNT looked like a skein serving bacteria favorable site for adhesion. Column experiments were performed over a range of CNT filter depth, pH, and ionic strength. Bacteria removal efficiency was found to increase from 44.15% to 99.95% as the CNT filter depth increased from 1 cm to 5 cm, and 3 cm of CNT filter depth was required for significant removal of bacteria. pH increase from 5.5 to 8.5 decreased the bacteria removal efficiency, due to the electrostatic repulsion between bacteria and CNT at higher pH. Bacteria removal efficiency decreased from 97.25% to 70.90% as the ionic strength increased from 0 mM to 50 mM. This study demonstrated that the CNT can be applied to slow sand filtration for treating microbially contaminated water.

• Analytical Science and Technology
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• v.18 no.4
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• pp.298-308
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• 2005

The methods for determining C-14 and tritium contents in the spent nuclear fuel sample were developed. The carbon-14($^{14}CO_2$) released during the dissolution of the spent fuel sample and $CaCO_3$ ($CO_2$ carrier) with 8 M $HNO_3$ at $90^{\circ}C$ was collected in trap containing 1.5 M NaOH. The volatile radioactive iodine evolved when the spent fuel was dissolved, was trapped on to Ag-silicagel (Ag-impregnated silicagel) adsorbent in column which is connected to two NaOH traps. The solutions which contain tritium as HTO after fuel dissolution were decontaminated by deionization with a mixture of cation and anion exchange resins and inorganic ionexchangers. The amount of C-14 in the trap solutions and the HTO concentration in the resulting deionization water were then determined by liquid scintillation counting.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.456-460
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• 2021

A potentiometric sodium-ion (Na⁺) sensor was prepared using a screen-printing process with carbon and silver inks. The two-electrode configuration of the sensor resulted in potential differences in Na⁺ solutions according to Nernstian equation. The obtained Na⁺-sensor exhibited an ideal Nernstian sensitivity, fast response time, and low limit of detection. The Nernstian response was stable when the sensor was tested for repeatability and long-term durability. The Na⁺-selective membrane coated onto the carbon electrode selectively passed sodium ions against interfering ions, indicating an excellent selectivity. The portable Na⁺-sensor was finally fabricated using a printed circuit system, demonstrating the successful measurements of Na⁺ concentrations in various real samples.

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.158-158
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• 1999

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1997.10a
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• pp.41-42
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• 1997